Fruit antioxidant activity, ascorbic acid, total phenol, quercetin, and carotene of Irwin mango fruits stored at low temperature after high electric field pretreatment

Greenhouse-grown tree ripe (TR) and mature green (MG) mangoes (cv. Irwin) were exposed to high electric field treatment before 20 and 30 days of storage at 5 degrees C. MG fruits were allowed to ripen at room temperature after low-temperature storage. Fruit physical quality attributes, ascorbic acid, carotene, quercetin, total phenols, and antioxidant capacity were estimated before and after the storage period. Antioxidant capacity of fruit juice was estimated using the ferric reducing antioxidant power (FRAP) assay. Fruit firmness decreased significantly during storage. Titratable acidity decreased 20 days after storage. Total soluble solids did not change during storage. Antioxidant capacity of fruits remained unchanged up to 20 days of storage period and decreased thereafter. Total phenol and carotenes increased during storage. Antioxidant capacity of fruits was significantly correlated only to ascorbic acids. Peel color and carotenes were higher in TR fruits, whereas titratable acidity and firmness were higher in MG fruits. There was no significant difference in other parameters between the stages of picking. Electric field pretreatment affected the respiration and antioxidant capacity of TR fruits and did not have any significant affect on other parameters. TR mangoes of cv. Irwin are more suitable for low-temperature storage and can be successfully stored for up to 20 days at 5 degrees C without any significant losses in functional properties and quality attributes.     

Design of hammerhead ribozymes that cleave murine Sry mRNA in vitro and in vivo

As the first step in investigating the possiblity of applying ribozyme technology to artificial control of the sex ratios at birth in farm animals, where the demand for females exceeds that for males, we designed a hammerhead ribozyme (HHRz) and 2 tRNA(val)-hammerhead ribozyme complexes (tRNARz3 and tRNARz4), and examined their effects upon murine Sry mRNA in vitro and in cells. We demonstrated that HHRz and tRNARz3 could effectively cleave the target Sry mRNA in vitro. For the purpose of experiments in vivo, HHRz was cloned into the highly efficient pUC-CAGGS mammalian expression vector (pCAG/HHRz), and the tRNA ribozyme complexes were cloned into the pol III promoter-driven pPUR-KE vector (pPUR/tRNARz3 and pPUR/tRNARz4); the ribozyme vectors were co-transfected with the target vector (pCAG/Sry). A suppressive action (up to approx. 60%) was confirmed for pCAG/HHRz and pPUR/tRNARz3 upon the transiently expressed exogenously introduced Sry in M15 cultured cells.     

Vertical soil–air CO2 dynamics at the Takayama deciduous broadleaved forest AsiaFlux site

At the Takayama deciduous broadleaved forest Asiaflux site in Japan, the ecosystem carbon dynamics have been studied for more than two decades. In 2005, we installed non-dispersive infrared CO₂ sensors in the soil below the site’s flux tower to systematically study vertical soil–air CO₂ dynamics and explain the behavior of soil surface CO₂ efflux. Soil–air CO₂ concentrations measured from June 2005 through May 2006 showed sinusoidal variation, with maxima in July and minima in winter, similar to the soil CO₂ effluxes measured simultaneously using open-flow chambers. Soil–air CO₂ concentrations increased with soil depth from 5 to 50 cm: from 2,000 to 8,000 ppm in the summer and from 2,000 to 3,000 ppm in the winter under snow. Summer soil–air CO₂ concentrations were positively correlated with soil moisture on daily and weekly scales, indicating that the Oi, Oe, and A horizons, where decomposition is accelerated by high-moisture conditions, contributed substantially to CO₂ emissions. This result is consistent with the short residence time (about 2 h) of CO₂ in the soil and larger emissions in shallow soil layers based on our diffusion model. We revealed for the first time that soil–air CO₂ concentrations in winter were correlated with both snow depth and wind speed. CO₂ transfer through the snow was hundreds of times the gas diffusion rates in the soil. Our estimate of the CO₂ efflux during the snow-cover season was larger than previous estimates at TKY, and confirmed the important contribution of the snow-cover season to the site’s carbon dynamics.     

Proceedings of the 2013 Joint JSTP/NTP Satellite Symposium

The first joint Japanese Society of Toxicologic Pathology (JSTP) and National Toxicology Program (NTP) Satellite Symposium, entitled “Pathology Potpourri,” was held on January 29^th at Okura Frontier Hotel in Tsukuba, Ibaraki, Japan, in advance of the JSTP’s 29^th Annual Meeting. The goal of this Symposium was to present current diagnostic pathology or nomenclature issues to the toxicologic pathology community. This article presents summaries of the speakers’ presentations, including diagnostic or nomenclature issues that were presented, select images that were used for audience voting or discussion, and the voting results. Some lesions and topics covered during the symposium include: treatment-related atypical hepatocellular foci of cellular alteration in B6C3F1 mice; purulent ventriculoencephalitis in a young BALB/c mouse; a subcutaneous malignant schwannoma in a RccHan:WIST rat; spontaneous nasal septum hyalinosis/eosinophilic substance in B6C3F1 mice; a rare pancreatic ductal cell adenoma in a young Lewis rat; eosinophilic crystalline pneumonia in a transgenic mouse model; hyaline glomerulopathy in two female ddY mice; treatment-related intrahepatic erythrocytes in B6C3F1 mice; treatment-related subendothelial hepatocytes in B6C3F1 mice; spontaneous thyroid follicular cell vacuolar degeneration in a cynomolgus monkey; congenital hepatic fibrosis in a 1-year-old cat; a spontaneous adenocarcinoma of the middle ear in a young Crl:CD(SD) rat; and finally a series of cases illustrating some differences between cholangiofibrosis and cholangiocarcinoma in Sprague Dawley and F344 rats.     

Starch Damage and Pasting Properties of Rice Flours Produced by Dry Jet Grinding

Milling method and particle size affect some properties of rice flour. To prepare ultra‐fine rice flour of <30 μm, hammer and dry jet grinding methods were examined and the effect of particle size on starch damage and pasting properties of the flour were elucidated. A jet mill could make finer flour (<10 μm mean size) with a narrower particle size distribution than a hammer mill could. Starch damage increased dramatically at a mean size of <10 μm. Particles of a similar size (<60 μm) had different levels of starch damage between mills. Not only the particle size, but also the milling method affected the level of damaged starch. Flour samples of ≥45 μm mean size had similar viscosity curves, but samples of <20 μm had different curves. Peak viscosity and final viscosity decreased sharply at <10 μm. Setback viscosity for particles of 3 μm from both brown rice and white rice were higher than the peak viscosity. Stability to heat and shearing stress were decreased for <20 μm flours as the breakdown viscosities decreased. Starch damage and pasting properties of flour ground from the nonwaxy japonica cultivar Koshihikari changed dramatically at a mean size of <10 μm.     

Nitrous oxide evolved from soil covered with plastic mulch film in horticultural field

Soil solarization practice, in which soil is covered with plastic mulch film and exposed to high temperature prior to crop cultivation, is expected to be an effective method for reducing weeds and pathogenic microorganisms without using agricultural chemicals. Although the production of nitrous oxide (N₂O), a major greenhouse gas, is enhanced in fertilized soil covered with plastic mulch films, its transport route to the atmosphere has not been sufficiently elucidated to date. In this study, we investigated the N₂O evolution from plastic-mulch-film-covered agricultural soil. In a horticultural field where ridge soil was covered with a plastic mulch film after fertilization, we observed significant N₂O flux from the soil surface of the unfertilized furrow between the ridges, indicating the horizontal diffusion of N₂O from the ridge soil covered with the mulch film to the adjacent furrow soil surface. On the other hand, the measurement of the permeance (permeation coefficient) of the plastic mulch film for gaseous N₂O by laboratory experiment revealed that N₂O gradually permeated the mulch film; the permeance increased exponentially with an increase in ambient temperature, indicating possible N₂O emission by permeation through the mulch film under field conditions. In winter, the amount of N₂O emission by permeation through the mulch film was estimated to be lower than that emitted from the furrow soil surface, and it was lower than that in summer. On the other hand, it was estimated to be much higher in summer owing to the higher permeance of the film at high temperatures.     

Clinical and clinico-pathologic characteristics of Shiba dogs with a deficiency of lysosomal acid beta-galactosidase: a canine model of human GM1 gangliosidosis

The present study was conducted to determine the clinical and clinico-pathologic characteristics of Shiba dogs with GM1 gangliosidosis, which is due to an autosomal recessively inherited deficiency of lysosomal acid beta-galactosidase activity. Clinical and clinico-pathological features were investigated in 10 homozygous Shiba dogs with GM1 gangliosidosis. The age at onset was 5 to 6 months and the dogs manifested progressive neurologic signs including loss of balance, intermittent lameness, ataxia, dysmetria and intention tremor of the head. The dogs were unable to stand by 10 months of age due to a progression of ataxia and spasticity in all limbs. Corneal clouding, a visual defect, generalized muscle rigospasticity, emotional disorder and a tendency to be lethargic were observed at 9 to 12 months. The dogs became lethargic from 13 months of age. The survival period seemed to be 14 to 15 months. As a clinico-pathologic feature, lymphocytes with abnormally large vacuoles were observed in peripheral blood (30 to 50% of total lymphocytes) through the lifetime of the dogs. The clinical and clinico-pathologic characteristics of this animal model are useful for not only the development and testing of potential methods of therapy, but also the diagnosis of affected homozygous Shiba dogs in veterinary clinics.     

Comparison of polymerase chain reaction-restriction fragment length polymorphism assay and enzyme assay for diagnosis of G(M1)-gangliosidosis in Shiba dogs.

In the present study, diagnostic methods for canine G(M1)-gangliosidosis were examined by comparing a DNA mutation assay with an enzyme assay. Sixty-two Shiba dogs of a pedigree with G(M1)-gangliosidosis were differentiated into 3 genotypes, i.e., normal, heterozygous, and homozygous affected dogs, using a DNA mutation assay, which consists of polymerase chain reaction amplification and the determination of restriction fragment length polymorphisms. The beta-galactosidase activity in leukocytes, umbilical cords, and plasma was measured using 4-methylumbelliferyl beta-D-galactoside and p-nitrophenyl beta-D-galactoside as artificial substrates and compared among the 3 genotypes. The results showed that it was possible to identify homozygous dogs with the enzyme assay using leukocytes and umbilical cords. When using leukocytes, heterozygous carriers could be differentiated from normal dogs in many cases. However, the use of the DNA mutation assay is essential for a complete determination of heterozygous carriers because of the overlap in the distribution of enzyme activity between these 2 groups. When umbilical cords were used, heterozygous carriers could not be differentiated from normal dogs because of no significant difference in enzyme activity between these 2 groups. The beta-galactosidase activity in plasma was not applicable to the diagnosis and genotyping of G(M1)-gangliosidosis in Shiba dogs.