Effect of protein malnutrition on the skin epidermis of hairless mice

The purpose of this study was to evaluate the effect of protein malnutrition on the skin epidermis of mice. A low protein diet induced thinning of the skin epidermis, a decrease of cell proliferative activity in epidermal cells and a decrease of stratum corneum hydration. Dityrosine was immunostained in the cytoplasm of epidermal cells in the low protein diet group. Plasma advanced oxidation protein product (AOPP) levels were significantly more increased in the low protein diet group than in the control diet group. These results suggest that protein malnutrition adversely affects the structure and water barrier and reservoir functions of the skin epidermis, and these pathological changes are associated with the expressions of protein oxidation markers, dityrosine and AOPP.     

A sero-survey of subtype H3 influenza A virus infection in dogs and cats in Japan

A sero-epidemiological survey of human and equine H3 influenza A virus infections in dogs and cats using the hemagglutination inhibition (HI) and neuraminidase inhibition (NI) tests was conducted. Serum samples were collected from 582 dogs and 237 cats in Japan during the periods 2002-2008 and 1997-2008, respectively. Although no HI antibodies against equine H3 virus were detected, 9 (3.8%) from cats and 12 (2.1%) from dogs were HI-positive against human H3 virus. Only one serum each from dogs and cats was NI-positive against N2 virus. These findings suggest that although equine H3 influenza virus infections have not been prevalent in companion animals, human H3N2 influenza A virus infections have occurred in dogs and cats in recent years in Japan.     

Molecular genetic and pathogenic characterization of psittacid herpesvirus type 1 isolated from a captive galah (Eolophus roseicapillus) in Japan

Psittacid herpesvirus type 1 (PsHV-1) was isolated from a captive galah (Eolophus roseicapillus) in Japan that was suspected of having Pacheco's disease (PD), an acute fatal disease in psittacine birds. PsHV-1 has been classified into four genotypes based on the UL16 gene sequence. In the present study, we investigated the genetic and pathogenic characteristics of the isolated virus, FOY-1, compared with a reference strain, RSL-1. The FOY-1 strain was classified into PsHV-1 genotype 2. The FOY-1 strain was found to be less pathogenic to budgerigars than RSL-1, which was classified as genotype 4 in an in vivo study. This is the first report regarding the classification of originally isolated PsHV-1 in Japan and its characterization by animal infection experiment.     

Gene expression and hormonal regulation of adiponectin and its receptors in bovine mammary gland and mammary epithelial cells

Although the functions of adiponectin, a differentiated adipocyte‐derived hormone, in regulating glucose and fatty acid metabolism are regulated by two subtypes of adiponectin receptors (AdipoRs; AdipoR1 and AdipoR2), those in ruminants remain unclear. Therefore we examined the messenger RNA (mRNA) expression levels of adiponectin and its receptors in various bovine tissues and mammary glands among different lactation stages, and the effects of lactogenic hormones (insulin, dexamethasone and prolactin) and growth hormone (GH) on mRNA expression of the AdipoRs in cultured bovine mammary epithelial cells (BMEC). AdipoRs mRNAs were widely expressed in various bovine tissues, but adiponectin mRNA expression was significantly higher in adipose tissue than in other tissues. In the mammary gland, although adiponectin mRNA expression was significantly decreased at lactation, AdipoR1 mRNA expression was significantly higher at peak lactation than at the dry‐off stage. In BMEC, lactogenic hormones and GH upregulated AdipoR2 mRNA expression but did not change that of AdipoR1. In conclusion, adiponectin and its receptor mRNA were expressed in various bovine tissues and the adiponectin mRNA level was decreased during lactation. These results suggest that adiponectin and its receptors ware changed in mammary glands by lactation and that AdipoRs mRNA expression was regulated by different pathways in BMEC.     

Visualization of 15O-water flow in tomato and rice in the light and dark using a positron-emitting tracer imaging system (PETIS)

Abstract

¹⁵P-water flow from the roots to the top in tomato (Lycopersicon esculentum Mill.) and rice (Oryza sativa L.) plants was visualized with time using a positron-emitting tracer imaging system (PETIS). The ¹⁵O-water flow was switched on by light and completely stopped in the dark. The flow rate in the stem of tomato and the shoot of rice at a light intensity of 500 μmol·m^?2·s^?1 was 1.9 and 0.4 cm min^?1, respectively.     

Effect of placement of urea and coated urea fertilizers on yield and quality of soybean (Glycine max (L.) Merr.) seeds

The objective of the present study was to record the seed yield and to examine visually the quality of soybean seeds cultivated under different types and placements of urea fertilizers. In addition to the conventional fertilizer application (including ammonium sulfate 16 kg N ha^-1 broadcasting (100 kg N ha^-1 of urea (0B) and X00-d type coated urea CU-100 (CUB), and deep placement (100 kg N ha^-1) of urea (UD) and 100-d type coated urea CU-100 (CUD) was conducted in separate plots in a paddy field converted to an upland field located at Shindori Experimental Station of Niigata University. Soybean plant growth was periodically analyzed and the quality of harvested seeds was also visually examined (hereafter referred to as “visual quality”). It was found that the deep placement treatments were more conducive 1o nitrogen (N₂)fixation, based on the relative mreide N concentration in the xylem sap, which is a good indicator of N~fixation by soybean. Also the total seed yield was the highest in CUD (82 g plant^-1) and 0D (81 g plant^-1), compared to the control (62 g plant^-1), UB (68 g plant^-1), and CUB (68 g plant^-1). The visual quality of harvested seeds showed that CUD enhanced the quality of seeds compared to the other treatments, in which the percentage of good quality seeds, hereafter referred to as "good seeds," based on the dry weight was 51 (control), 65 (K3B), 61 (CUB), 61 (0D), and 6696 (CUD). In terms of diseased seeds, the percentage of turtle wrinkle and broken seed coats was found to decrease by N application compared to the control. Thus, it is suggested that N fertilization management is important for maximum yield of soybean as well as for the enhancement of seed quality.     

Free polyamine concentrations in coastal seawater during phytoplankton bloom

SUMMARY: Polyamines are widely distributed in nature and known to have many roles in living organisms. We investigated the concentrations of polyamines together with inorganic nutrients during a summer bloom period in the Seto Inland Sea of Japan. Putrescine and spermidine were the major polyamines in the coastal seawater. The concentrations at 1 m depth varied widely during the sampling period and ranged from 2.0 to 32.6 nM and 1.0 to 14.1 nM. Spermine concentrations were much lower than putrescine and spermidine. In addition, other polyamines (diaminopropane, cadaverine, norspermidine, homospermidine, norspermine) were also detected. Putrescine and spermidine seemed to be significant compounds in dissolved organic nitrogen in coastal seawater.     

Residual effects of cultivation methods on weed seed banks and weeds in Cambodia

The effects of the planting method (transplanting vs. direct seeding), rice cultivar (Sen Pidao vs. Phka Rumduol), and herbicide application (admixture of bentazone and cyhalofop‐butyl) on weeds and weed seed banks were quantified in unflooded, shallowly flooded, and deeply flooded paddy fields in Cambodia in 2005 and 2006. Broad‐leaved weeds infested more toward maturity in 2006 than in 2005, particularly in directly seeded plots. Weed dry weights at pre‐heading and/or maturity were consistently reduced by herbicide application and Phka Rumduol cultivar, while weed numbers increased under unflooded condition. The proportion of sedges was consistently larger in directly seeded and non‐herbicide plots at pre‐heading. Larger numbers and dry weights of sedges and total weeds in 2005 caused larger seed bank sizes of sedges and total weeds in 2006, which further caused their infestation in 2006. A greater weed dry weight at 62 days after sowing in 2005 resulted in larger seed banks of Cyperus iria and Fimbristylis miliacea, which were most severe under non‐herbicide, direct‐seeded treatment, while that at rice maturity resulted in larger seed banks of Cyperus difformis, Scirpus juncoides, and Lindernia antipoda. Overall, sedges shared the majority of the total weed seed bank, followed by broad‐leaved weeds and then grasses. A lower yield in 2005 led to significantly larger seed bank sizes of sedges, but not of grasses or broad‐leaved weeds. Rice yield reduction was consistently related to larger numbers of sedges by heading and those of grasses at maturity.     

GnRHa-induced spawning of wild-caught jack mackerel Trachurus japonicus

The jack mackerel Trachurus japonicus is a key commercially exploited fish species in Japan. The rearing experiment often provides information that is useful for understanding the reproductive characteristics of wild stocks; however, there has been no study on spawning in captive T. japonicus. In the study reported here, we induced spawning in T. japonicus caught in the wild by hook and line. Females with fully vitellogenic oocytes and males during spermiation were selected by gonadal biopsy and injected with gonadotropin-releasing hormone analog (GnRHa) mixed in molten coconut butter. This treatment was performed four times in different groups of four females and five to eight males, and each group was maintained in a 3-m³ concrete tank. We observed the first spawning at 1 or 2 days post-injection and collected between 41,690 and 149,450 eggs. Spawning was recorded on 18 consecutive days in one experiment and for 3 days continuously in the other experiments. In the former, spawning ended when the water temperature reached 23 °C and occurred mainly between 2100 and 2400 hours. These results indicate that GnRHa-induced spawning may be useful for evaluating the reproductive characteristics of T. japonicus and obtaining fertilized eggs to conduct larval experiments.