Chemotactic activity of hemocytes derived from two marine neritid gastropod molluscs, Nerita albicilla and Heminerita japonica, to Vibrio parahaemolyticus and Escherichia coli strains.

Hemocytes of two marine neritid gastropods, Nerita albicilla and Heminerita japonica, were attracted chemotactically to live Vibrio parahaemolyticus and Escherichia coli strains. Chemotactic attraction of N. albicilla hemocytes was enhanced in the presence of N. albicilla plasma, while that of H. japonica hemocytes was not enhanced in the presence of H. japonica plasma. Chemotactic activity of the hemocytes seems to participate in the rapid elimination of V. parahaemolyticus from these gastropods.     

A study of reproductive performance in pregnant, IL-2 receptor beta-chain overexpressed transgenic mice

Relationships between female reproductive performance and uterine natural killer (uNK) cells were investigated in pregnant IL-2 receptor beta-chain overexpressed transgenic (Tg2Rbeta) mice. At 8 days of pregnancy, all fetuses were alive, suggesting that implantation normally occurred in these mice. However, 47% of fetuses were dead at 10 days of pregnancy and at 12 days all fetuses were resorbing, indicating that fetal loss progressed with the advance of pregnancy. The placenta of Tg2Rbeta mice gradually decreased in weight with the advance of pregnancy. At 10 days the placental labyrinth, decidua basalis, and metrial gland in Tg2Rbeta mice were poorly developed, and more uNK cells were found in Tg2Rbeta mice than in the control mice. We propose that Tg2RPbeta mice are the first and interesting model that uNK cells can cause abortion, to clarify the involvement of uNK cell function in female reproductive performance.     

Depletion of stored nutrients during fasting in Nile tilapia (Oreochromis niloticus) juveniles

We evaluated growth performance and metabolic responses in Nile tilapia (Oreochromic niloticus) juveniles (30.2 ± 0.9 g) subjected to 1 (F1), 2 (F2), or 3 weeks (F3) of fasting and then refed for 10 weeks (10WR) compared to controls (FC), which were fed for the full 13-week trial. Weight gain and specific growth rate (SGR) during fasting were lower in all treatments compared to the FC. However, during refeeding, feed intake/body mass and SGR increased in F1, F2, and F3, inducing partial compensatory growth. The hepatosomatic index (HSI), visceral fat index (VFI), liver glycogen (LG), and carcass lipid levels dropped in all fasted fish compared to FC (P < 0.05), showing a depletion of stored nutrients such as fat and LG. Along with LG, fat reserves were mobilized during fasting to maintain basal metabolism and survival, but these energy constituents returned to control levels at 10WR, at which time HSI was higher in all refed fish compared to FC. Additionally, the variables VFI, LG, and lipid in carcass increased in all refed fish, equaling those of FC at 10WR. The results showed that, in contrast with other protocols that used smaller tilapia juveniles, the feeding strategies utilized for Nile tilapia juveniles in this study (1 to 3 weeks of fasting and 10WR) were able to induce only partial compensatory growth. It can be concluded that in situations that require complete food restriction in juvenile Nile tilapia (30 g), an acceptable strategy is to limit the period of fasting to 1 week or less to minimize losses and to achieve partial compensatory growth.     

Pyrrhotites: synthetics having two new superstructures

Synthetic pyrrhotites Fe(1-x)S, synthesized at various compositions and temperatures, show the presence of two new superstructures based on the hexagonal subcell of the NiAs type (axes A and C): one, in the range 1-x=0.89 to 0.93, has a = 90A and c = 3C; the other, in the range 1 -x = 0.935 to 0.975, has a = 2A but c irrationally related to C, varying with composition.     

Eastern blotting and immunoaffinity concentration using monoclonal antibody for ginseng saponins in the field of traditional chinese medicines

Ginsenosides separated by silica gel TLC blotted to a PVDF membrane that was treated with a NaIO4 solution followed by bovine serum albumin (BSA) resulted in a ginsenoside-BSA conjugate on a PVDF membrane. The blotted spots were stained by anti-ginsenoside Rb1 (G-Rb1) and -Rg1 (G-Rg1) monoclonal antibodies (MAbs). The newly established immunostaining method, Eastern blotting, was applied for the determination of ginsenosides possessing protopanaxadiol and/or protopanaxatriol in the traditional Chinese medicine (TCM). This method developed a new way to separate the ginsenoside molecule into two functional parts using a simple and well-known chemical reaction. The sugar parts were oxidized by NaIO4 to give dialdehydes, which reacted with amino groups of the protein and covalently bound to the adsorbent PVDF membrane. The MAb bound to the aglycon part of the ginsenoside molecule for immunostaining. Double staining of Eastern blotting for ginsenosides using anti-G-Rb1 and -Rg1 MAbs promoted complete identification of ginsenosides in Panax species. The immunoaffinity concentration of G-Rb1 was deteremined by immunoaffinity column conjugated with anti-G-Rb1 MAb leading to the knock-out extract, which will be useful for the pharmacological investigation. To concentrate and determine G-Rb1 in P. japonicus, the crude extract of P. japonicus was fractionated by immunoaffinity column conjugated with anti-G-Rb1 MAb. Two ginsenosides, chikusetsusaponins III and IV having protopanaxadiol as an aglycon, were identified by Eastern blotting, although it was expected that G-Rb1 might be a component of P. japonicus by enzyme-linked immunosorbent assay (ELISA) analysis.     

Restoration of Breadmaking Properties to Frozen Dough by Addition of Sugar and Yeast and Subsequent Processing

We prepared bread dough A (a mixture of wheat flour, sugar, salt, and water), bread dough B (a mixture of bread dough A and yeast), and bread dough C (first‐proofed, molded, and second‐proofed bread dough B) and froze them at –20°C for six days. They were thawed at 4°C for 16 hr and subjected to their breadmaking processes. The results indicated that breadmaking properties (bread height [mm] and specific volume [cm³/g]) after bread dough A and B processes were the same as those of control bread dough (unfrozen dough). However, in the case of bread dough C, the resulting bread showed depression of the properties. The amount of centrifuged liquid from thawed bread dough C increased. Sugar was added to thawed bread dough C (bread dough C‐1), and then yeast was further added to bread dough C‐1 (bread dough C‐2), and they were subjected to the breadmaking process. The results showed that the breadmaking properties of bread dough C‐2 were the same as those of the control. It was further found that when the first proof step in the bread dough C‐2 process was omitted, the breadmaking properties were depressed. Frozen and thawed bread dough C was packed into a plastic tube, and extension of the dough was compared with that of control dough under reduced pressure. Bread dough C extended to 50 mm, compared with 70 mm for control dough. First proof, mold, and second proof steps of dough C‐2 caused it to extend to the same height as control dough. It was concluded that the increased amount of the separated liquid in thawed dough C caused depression of breadmaking properties resulting from lack of water in the appropriate places to provide the expected properties, but these properties could be restored to the levels of control bread dough by the addition of sugar and yeast following the first proof, mold, and second proof steps.     

Seasonal and spatial variations in leaf nitrogen content and resorption in a Quercus serrata canopy

To elucidate the relationships between spatiotemporal changes in leaf nitrogen (N) content and canopy dynamics, changes in leaf N and distribution in the canopy of a 26-year-old deciduous oak (Quercus serrata Thunb. ex. Murray) stand were monitored throughout the developmental sequence from leaf expansion to senescence, by estimating the leaf mass and N concentrations of all the canopy layers. Seasonal changes were observed in leaf N concentration per unit leaf dry mass (N (m)), which peaked after bud burst, declined for two weeks shortly thereafter, and then remained constant for the rest of the growing season for each canopy layer. Leaf N concentration per unit leaf area (N (a)) was higher in the upper layer than in the lower layer throughout the growing season, and was closely correlated with relative irradiance (RI) in the summer when the air temperature was moderately high. The N concentrations of all leaf layers started to decrease in November, and reached their lowest values in late November, whereas LMA scarcely changed throughout the season. The lowest N concentrations did not differ significantly among the canopy layers. Seasonal changes in the relationship between N (a) and RI were detected, indicating that N (a) is optimized temporally as well as spatially. Nitrogen resorption efficiency was highest in the upper canopy layers where larger amounts of N were invested. Based on the estimates of leaf mass and leaf N concentrations of the canopy layers, total leaf N concentration of the whole canopy was estimated to be 84.1 kg ha(-1) in the summer, and 37.3 kg ha(-1) in late November. Therefore, 46.8 kg ha(-1) of leaf N in the canopy (about 56% of the total N) was resorbed just before leaf abscission.