Behavior of nitrogen in the media supplied with the aqueous phase produced by methane fermentation as liquid fertilizer

pp. 859–864
Behavior of nitrogen in the media was investigated when the aqueous phase produced by methane fermentation was supplied as liquid fertilizer.
When the aqueous phase was supplied to masa-soil,      included in masa-soil was nitrified to      . Additionally, in masa-soil,       absorption was observed. On the other hand, in the case of coconut fiber and rockwool,     has been hardly nitrified. From above results, it was determined that       toxic effect from the aqueous phase on tomato plants growth was inhibited by means of the progress of nitrification and       absorption by masa-soil.
  However, nitrification was restrained so that       was fixed in masa-soil. On the other hand, in the sampled field soil,       was not fixed, and was nitrified immediately. In the field soil, there was a great deal of generated      . In comparison with masa-soil.     

The hypocholesterolemic activity of transgenic rice seed accumulating lactostatin, a bioactive peptide derived from bovine milk β-lactoglobulin

Lactostatin is a novel pentapeptide (IIAEK) derived from bovine milk β-lactoglobulin with greater hypocholesterolemic activity than β-sitosterol, the drug commonly used to treat hypercholesterolemia. We developed transgenic rice expressing lactostatin as a fusion protein with seed storage protein (SSP) glutelins under the control of three different endosperm-specific promoters. Lactostatin accumulated in transgenic rice seed at approximately 1.6 mg/g seeds (dry seeds) without any apparent influence on seed traits such as endogenous SSP expression levels or alterations in the intracellular structures of endosperm cells. Short-term (three day) oral administration of the glutelin fraction containing lactostatin (namely three times of 300 mg/kg body weight/day) extracted from transgenic rice seeds resulted in hypocholesterolemic activity in rats; namely, the serum low-density-lipoprotein (LDL) cholesterol level was significantly reduced accompanied by a significant increase in beneficial serum high-density-lipoprotein (HDL) cholesterol.     

Uterine Carcinosarcoma in a 2-year-old Female Wistar Hannover GALAS Rat

Carcinosarcomas are rare tumors in humans as well as rats and most commonly occur in the uterus. Recently, we observed a case of incidental carcinosarcoma of the uterus in a female Wistar Hannover GALAS [BrlHan:WIST@ Jcl (GALAS)] rat at 2 years of age. Histopathologically, the tumor was characterized by an admixture of malignant epithelial and nonepithelial elements. The carcinomatous components represented a type of endometrial carcinoma, consisting of glandular and solid proliferation of large-sized tumor cells. Prominent mitoses and tumor cell invasion were observed. The sarcomatous components were characterized by multifocal proliferation of severe atypical cells with cartilage matrix and were diagnosed as chondrosarcoma. Transitions between carcinomatous and sarcomatous components were observed, and many tumor cells in the solid lesion showed immunohistochemical reactivity with both cytokeratin and vimentin. Based on these findings, this tumor was diagnosed as a uterine carcinosarcoma. This is the first report of uterine carcinosarcoma in Wistar Hannover GALAS [BrlHan:WIST@Jcl (GALAS)] rats.     

Leptin inhibits hepatocyte growth factor-induced ductal morphogenesis of bovine mammary epithelial cells

We examined the effect of stroma-derived factors, hepatocyte growth factor (HGF) and leptin, on morphological differentiation of bovine mammary epithelial cells (BMEC) in collagen gel three-dimensional culture in vitro. BMEC treated with HGF, but not leptin, formed duct-like organoids. The formation of organoids by HGF was enhanced by treatment with a mixture of insulin, cortisol and prolactin, while BMEC treated with the mixture alone did not produce the organoid. In contrast, the formation of organoids by HGF was dose-dependently inhibited by simultaneous addition of leptin, regardless of the presence or absence of the hormone mixture. These results suggest that stroma-derived factors intricately regulate mammary epithelial morphogenesis.     

Use of soil nonexchangeable potassium by paddy rice with clay structural changes under long-term fertilizer management

To prove the hypothesis that paddy rice utilizes soil nonexchangeable potassium (neK) and causes associated structural changes in clay minerals, K status and clay mineralogy of 22 surface soils from three paddy fields under long-term fertilizer management for 51–93 years were investigated. Soil neK content was determined as the difference between 1 mol L⁻¹ hot HNO₃ extractable K and 1 mol L⁻¹ ammonium acetate exchangeable K. Clay mineralogy was identified by X-ray diffraction (XRD). The radiocesium interception potential (RIP), an index of frayed edge sites in the interlayer sites of 2:1 type clay minerals, was also determined. The neK contents under the -K and NPK treatments were considerably lower than those under the unfertilized treatment in all the fields, indicating the exploitation of soil neK by rice. XRD analysis of the clay samples revealed 7% shift from the 1.0 peak to 1.4 nm one under the -K treatment compared with the unfertilized one, and the amounts of neK were negatively correlated with those of RIP (p < .01), suggesting the expansion of interlayer spaces of the 2:1 type phyllosilicates such as mica due to the release of neK. In addition, the neK content positively correlated with K balance of the long-term experiments (p < .05). The differences of neK between unfertilized K and -K treatments corresponded to 22–157 kg K ha⁻¹, or 0.42–1.68 kg K ha⁻¹ year⁻¹. In conclusion, utilization of considerable amount of soil neK under K depleted conditions should be considered to establish sustainable K management for paddy rice.     

Irradiation history of Itokawa regolith material deduced from noble gases in the Hayabusa samples

Noble gas isotopes were measured in three rocky grains from asteroid Itokawa to elucidate a history of irradiation from cosmic rays and solar wind on its surface. Large amounts of solar helium (He), neon (Ne), and argon (Ar) trapped in various depths in the grains were observed, which can be explained by multiple implantations of solar wind particles into the grains, combined with preferential He loss caused by frictional wear of space-weathered rims on the grains. Short residence time of less than 8 million years was implied for the grains by an estimate on cosmic-ray-produced (21)Ne. Our results suggest that Itokawa is continuously losing its surface materials into space at a rate of tens of centimeters per million years. The lifetime of Itokawa should be much shorter than the age of our solar system.     

Ferric iron transformation in soils with rotation of irrigated rice-upland crops and effect on soil tillage properties

We examined the relationship between the form of iron and the tillability (defined as the degree of ease of pulverizing a soil into small clods) of soils in upland fields that had been converted from paddy fields. The amount of iron (Fe.e) extractable with acetate buffer (pH 3.0) decreased from 0.959 g kg_-1 in a field that has been continuously used as a paddy field to 0.104 g kg-I in a field that had been converted into an upland field for a period of 5 y. There was no significant change in the free iron oxide content under upland conditions. These results indicate that ferric iron oxides are gradually crystallized to less reactive forms after the conversion of a paddy field into upland conditions. Both soil tillability (represented by the mean clod diameter after tillage) and the stability of the soil microstructure (represented by the sediment volume) also increased during the 3-y period after conversion and then remained constant for the last 2-y period of the study. On the basis of these results, two mechanisms for the improvement of soil tillability can be proposed as follows: crystallization of ferric iron oxides increased their resistance to microbiological reduction and due to this stabilization the iron oxides as a cementing reagent that contributed to the soil microstructure, which in turn affected the soil tillability. During the first year after drainage, however, there was no significant correlation between the soil tillability and amount of Fe_ac, presumably because the soil was not sufficiently dry in the first year after conversion, and the iron oxides did not affect appreciably the soil structure.