Islet recovery and reversal of murine type 1 diabetes in the absence of any infused spleen cell contribution

A cure for type 1 diabetes will probably require the provision or elicitation of new pancreatic islet beta cells as well as the reestablishment of immunological tolerance. A 2003 study reported achievement of both advances in the NOD mouse model by coupling injection of Freund's complete adjuvant with infusion of allogeneic spleen cells. It was concluded that the adjuvant eliminated anti-islet autoimmunity and the donor splenocytes differentiated into insulin-producing (presumably beta) cells, culminating in islet regeneration. Here, we provide data indicating that the recovered islets were all of host origin, reflecting that the diabetic NOD mice actually retain substantial beta cell mass, which can be rejuvenated/regenerated to reverse disease upon adjuvant-dependent dampening of autoimmunity.     

Promotive effect of soil solution on germination of Monochoria vaginalis under paddy conditions

ABSTRACT

Growth of the weed Monochoria vaginalis (Burm. f.) Kunth under the conditions of organic rice production is a serious problem. The reason for the growth of M. vaginalis being dominant, especially in organic rice production, is not fully understood. In this study, laboratory experiments were conducted to analyze soil and seed factors in relation to the promotion of germination. (1) After incubation of flooded soil with or without the addition of rice bran (0.3%, 0.6%, and 0.9% in an air-dried soil basis), soil solutions were recovered and seeds of M. vaginalis were incubated in the soil solutions. Germination in the soils solutions without and with 0.3% rice bran was greater than that in distilled water. However, germination was suppressed in the presence of 0.6% and 0.9% of rice bran. These findings indicate that the solution from the soils with rice bran has different effects that may either increase or decrease germination. (2) A mixture of air-dried soil and distilled water was filtered to obtain a soil solution. Seeds were incubated in the soil solution (same as above). Environmental and physiological factors affected germination: exposure of seeds to light was an environmental factor and high germination activity and shallow dormancy of seed were physiological. The recovered soil solution promoted germination when these factors were not optimized. (3) There was a negative and significant correlation between dissolved oxygen (DO) in the soil solution and germination, indicating that a low content of DO was a promotive factor for germination. (4) Based on an experiment using pH buffers, germination increased with decrease in pH of soil solution, as long as the pH ranged from 4.0 to 7.0. This finding indicates that pH is also a factor that promotes germination.     

Rapid semi-quantification of triacylglycerols,phosphatidylcholines, and free fatty acids in the rice bran of one grain

We developed a microplate assay method for determining the contents of triacylglycerols(TAGs), phosphatidylcholines(PCs), and free fatty acids(FFAs) in the rice bran of one grain using enzymatic reactions. In this method, enzymes from commercially available kits were used. Optimum reaction conditions were established. It was found that Nonidet P-40 was the optimal among the three surfactants used(Triton X-100, Tween 40, and Nonidet P-40) when lipid was dissolved in a reaction solution. Using this method, it was possible to quantify TAGs, PCs, and FFAs in concentration ranges of 7–150, 5–70, and 8–200 mg L~(–1), respectively. Furthermore, when the TAG contents in the rice bran were measured, the values closely corresponded to those obtained by extracting from large amounts of rice bran. However, sufficient data on the PC and FFA contents in rice bran are not available for valid comparisons. Although this method can accurately quantify the TAG contents in the rice bran of one grain, the accuracy of the PC and FFA contents has not been verified. Hence, future study is necessary.     

Effects of Environmental Temperature on Structure and Gelatinization Properties of Wheat Starch

The effects of environmental temperature on gelatinization properties and amylopectin structures of wheat endosperm starch were examined by isolating starches from four wheat cultivars matured in growth chambers at daytime temperatures of 15, 20, 25, or 30°C. Kernel weight and starch content per kernel were reduced by high maturation temperature. Amylose content showed no significant change at high maturation temperature in some cultivars; in other cultivars, there was a slight increase. Principal component analysis of data on relative peak areas of debranched amylopectin showed that amylopectin from wheat grown at a lower temperature had a greater proportion of shorter chains. Amylopectin branch chains were classified into three groups based on the correlation coefficients between the data of branch chain length distribution and principal component scores, degree of polymerization (DP) of 6–12, DP 13–34, and DP ≥ 35. The gelatinization temperature of starches increased markedly at a higher maturation temperature, with increases exceeding 10°C at high maturation temperatures. Gelatinization properties correlated significantly with amylopectin chain length distribution.