Wood density and carbon and nitrogen concentrations in deadwood of Chamaecyparis obtusa and Cryptomeria japonica

Estimating carbon (C) and nitrogen (N) stocks in deadwood in forests nationwide is required for understanding large-scale C and N cycling. To do so requires estimated values of wood density and C and N concentrations. Additionally, parameters that show variation should be examined. In this study, we clarified the estimated values and the variation in three parameters in each decay class of each of two tree species and examined whether dead log diameter and region contribute to variation in the parameters. Data were collected from 73 Chamaecyparis obtusa (Sieb. et Zucc.) Endl. plantations and 66 Cryptomeria japonica D. Don plantations throughout Japan. Wood densities decreased from 386 to 188?kg?m^?3 for C. obtusa and from 334 to 188?kg?m^?3 for C. japonica in decay classes 1–4. The variation in wood density increased with decay class, and the coefficient of variance increased from 13.9% to 46.4% for C. obtusa and from 15.2% to 48.1% for C. japonica. The N concentrations increased from 1.04 to 4.40?g?kg^?1 for C. obtusa and from 1.11 to 2.97?g?kg^?1 for C. japonica in decay classes 1–4. The variation in N concentration increased with decay class, and the coefficient of variance increased from 51.9% to 76.7% for C. obtusa and from 50.3% to 70.4% for C. japonica. Log diameter and region contributed to variations in wood density and N concentration in decay classes 1 and 2 for C. obtusa and C. japonica. However, no relationship was observed between regional climates and the two parameters. In contrast, C concentrations ranged from 507 to 535?g?kg^?1 and were stable with much lower coefficients of variance throughout the decay classes for both tree species. Thus, we recommend that the same C concentration can be adapted for all decay classes of both tree species.     

Chemical and morphological changes of porous hydrated calcium silicate in paddy soil

The chemical and morphological changes of porous hydrated calcium silicate material (PS) during the dissolution process in paddy soil were investigated by using both a scanning electron microscope (SEM) and an energy dispersive X-ray (EDX) analysis. The results showed that original PS consisted of agglomerate of various sizes with almost the same elemental composition. The SEM images at a high magnification showed that the original PS consisted of agglomerates of small platelike crystals (≦ μm) of tobermorite [Ca₅(Si₆O₁₈-H₂)·4H₂O]. On the other hand, elemental composition showed that the PS agglomerates in paddy soil altered to Si- and Ca-rich agglomerates after incubation for 53 d. The morphological differences between the two types of agglomerates were observed by SEM at a high magnification. The Si-rich agglomerates were similar to the original PS in morphology, whereas the Ca-rich agglomerate appeared as a large crystal. The X-ray diffraction patterns obtained in a previous study suggested the presence of quartz and calcite in PS after incubation for 53 d (Saigusa et al. 2000: Soil Sci. Plant Nutr., 46, 89–95). Si- and Ca-rich agglomerates were identified as silica skeletons of PS and calcite, respectively. It was suggested that the silica skeletons of PS remained as a silicon source for rice plants even after the disappearance of tobermorite revealed by the X-ray diffractogram.     

Phospholipid fatty acid composition of microbiota in the percolating water from a rice paddy microcosm

The microbiota in the percolating water from the plow layer soil in paddy fields was studied based on the composition of phospholipid fatty acids (PLFAs) in a pot experiment. The mean concentrations of PLFAs in the percolating water were 17±5 and 11±4 µg L^-1 in the planted and non-planted pots, respectively. The dominant PLFAs in the percolating water were 16: 0, 16: 1ω7c, 18: 1ω7, 18: 1ω9, il5: 0, and ail5: 0 PLFAs in both the planted and non-planted pots. The dominance percentage of 18: 3ω6c and 17: 1ω8 PLFAs increased at the late stage of rice growth in the planted pots. The percolating water from the planted pots contained in a higher percentage of straight mono-unsaturated PLFAs and a lower percentage of branched-chain PLFAs than that from the non-planted pots. Considerable differences in the PLFA composition in the percolating water were observed between the planted and non-planted treatments and with the duration of the growth period. Principal component analysis indicated that the microbiota in the percolating water was derived from the microbiota in the floodwater and in the plow layer soil. Cluster analysis showed that the similarity of the PLFA composition in the percolating water to the PLFA composition in the plow layer soil was higher than that in the floodwater. The stress factor that was estimated from the trans/cis ratio of 16: 1ω7 PLFA was 0.08±0.04 and 0.14±0.05 in the percolating water from the planted and non-planted pots, respectively, which indicated that the degree of stress on the microbiota in the percolating water from the planted pots was low in a similar way to the degree of stress on the microbiota in the floodwater, while the degree in the percolating water from the non-planted pots was similar to that in the plow layer soil, respectively.     

Responses of antioxidant enzymes in the needles of hinoki cypress (Chamaecyparis obtusa) seedlings to nutrient solutions containing various calcium/aluminum ratios

An attempt was made to examine the possible connection between the various ratios of calcium/aluminum (Ca/Al) in the nutrient solution of plant cultures and the active oxygen scavenging system of hinoki cypress (Chamaecyparis obtusa) seedlings. The hinoki cypress seedlings were transferred to nutrient solutions containing 5 mM AlCl₃ together with various concentrations of Ca(NO₃)₂ in pots containing glass beads and Teflon tips. The activities of superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX) and glutathione reductase (GR) in the needles were estimated at several stages during the 7-day treatment. The samples treated with the lower Ca/Al solutions show the highest SOD activities. The activities of APX and GR, both of them involved in the ascorbate-glutathione cycle, showed the same tendency with decrease to higher Ca/Al ratio. These results indicate that rhizospheric Ca might compete with Al and ameliorate Al toxicity on and in the roots, the Al stress is not transformed to the needles after a few days, and the ascorbate-glutathione cycle in the hinoki cypress needles might fluctuate and be suppressed by the rhizospheric Al stress during the 7 days. This work was supported in part by funding from the Japan Science & Technology Corporation, the CREST program 1996–2001, and the Center for Forest Decline Studies.     

Reactivity of green tea catechins with formaldehyde

In the reaction of green tea catechins with formaldehyde at room temperature (25°C), tea catechins were found to have reactivity. In particular, (-)-epicatechin gallate and (-)-epigallocatechin gallate, which have a galloyl moiety at the C-3 position, showed higher reactivity than (+)-catechin, (-)-epicatechin, or (-)-epigallocatechin. Reactivity of various kinds of simple phenolic compounds and flavonoids with formaldehyde was also examined. Among these compounds, only phloroglucinol showed reactivity to the same degree as that of nongalloylated catechins. These results suggest that factors for reactivity with formaldehyde at room temperature may be the presence of a phloroglucinolic A-ring structure and the absence of the electron-attractive group such as a carbonyl group in Cring. The comparison of the reactivity of 3-O-acylated catechins with that of 3-O-galloylated catechins indicated that only a galloyl group effectively enhanced reactivity with formaldehyde.     

Effects of whey protein hydrolysate on growth promotion and immunomodulation in mouse pups in artificial rearing system

This study aimed to investigate the effects of whey protein hydrolysate (WPH) on the growth and immunity of mouse pups in artificial rearing (AR) system. Mouse pups were reared in the AR system with artificial milk including 5% WPH (AR with WPH) or not (AR without WPH), and the remaining pups were reared by their mother (dam) for 14 days after birth. The body weight change and body weight gain rates in the AR with WPH group were significantly higher than those observed in the AR without WPH group and similar to those in the dam group. Moreover the feed and protein efficiencies in the AR with WPH group were significantly higher than those of the AR without WPH group. In addition, the supplement of WPH in the AR system was shown to significantly elevate the number of CD3⁺CD8⁺, B220⁺CD19⁺, IA/IE⁺CD11c⁺, and CD11b⁺ in the thymocyte and/or splenocyte, and the thymus weight. Furthermore, MALDI‐TOF/MS analysis identified the amino acid sequences corresponding to some peptides, and indicated that VRTPEVDDE had the highest relative intensity among the peptides from tested WPH. Therefore, WPH would be required to not only promote growth, but also exert immunomodulatory activities in mouse pups in AR system.     

Reduced mitotic activity and increased apoptosis of fetal sertoli cells in rat hypogonadic (hgn/hgn) testes

Sterility in male hypogonadic (hgn/hgn) rats results from congenital testicular dysplasia caused by a single recessive gene hgn on rat chromosome 10. We recently identified an insertion mutation in the Spag5/astrin gene of hgn/hgn rats that may cause defective proliferation of immature Sertoli cells in the postnatal hgn/hgn testis. Since the pathological alterations were present in the testes at birth, we examined the involvement of defective mitosis and apoptotic cell death in embryonic development of hgn/hgn testes. Testicular hypoplasia was apparent at embryonic day (ED) 18.5. Immunostaining of hgn/hgn testes at ED 21.5 with antibody to GATA-4, which is specific for fetal Sertoli cells in the seminiferous cords, showed that the significant decrease in the number of fetal Sertoli cells was accompanied by a two fold increase in their mitotic index and abnormal mitosis and apoptosis. Prior to this, we observed a decrease in the number of BrdU-labeled cells, an increase in the number of TUNEL-positive apoptotic cells, and presence of MIS-positive apoptotic cells in hgn/hgn testes on ED 17.5 and 18.5. These results suggest that the Spag5 mutation may cause a reduction in mitotic activity and an increase in apoptosis of fetal Sertoli cells in hgn/hgn testes.     

Growth of recombinant equine herpesvirus 1 (EHV-1) replaced with passage-induced mutant gene 1 and gene 71 derived from an attenuated EHV-1 in cell cultures and in the lungs of mice

The relationship of passage-induced mutant genes 1 and 71 of an attenuated equine herpesvirus 1 (EHV-1) with virulence was analysed by constructing nine recombinant EHV-1 viruses by homologous recombination. Gene 1 or/and gene 71 of a virulent EHV-1 strain, HH1, was replaced by a mutant gene 1 or/and 71 of an attenuated HH1 strain, BK343, respectively. The beta-galactosidase gene of Escherichia coli was inserted within the gene 1 or 71 coding sequence of HH1 to inactivate the genes. Virus replications of these recombinant viruses in cell cultures were similar, but release of the gene 71-inactivated virus from infected cells was delayed compared to that of the other viruses. Plaque sizes of the recombinant viruses were similar to those of HH1, but those of BK343 were significantly smaller, indicating an effect of some unknown factor(s) on viral cell-to-cell spread. The growth abilities of the recombinant viruses with a mutant gene 1 or/and 71 in lungs of mice were similar to those of HH1, but those of gene 71-inactivated viruses were reduced to the level of BK343 and the titers were about 100-times lower than those of the other recombinant viruses. These results indicate that the mutant genes 1 and 71 of BK343 might not confer an attenuated nature to EHV-1.     

A case of canine cutaneous clear cell adnexal carcinoma with prominent expression of smooth muscle actin

Cutaneous clear cell adnexal carcinoma was found in the right lip of a 14-year-old male castrated Shih Tzu. Histologically, the tumor mostly consisted of neoplastic cells with clear or vacuolated cytoplasms and contained frequent tubular structures. Neoplastic cells showed coexpression of pan-cytokeratin (CK) and vimentin by double-labeled immunofluorescence staining. In addition, immunohistochemistry revealed that the tumor cells were positive for pan-CK (AE1/AE3, KL1, CAM 5.2), CK-7, CK-8, CK-14, CK-15, CK-18, vimentin and alpha-smooth muscle actin (SMA) with varied intensity and positivity. Among these marker proteins, SMA was positive in 75% of the tumor cells. On the other hand, CK-15, which is a specific marker of follicular stem cells, was expressed in less than 1% of the tumor cells. Based on these findings, the tumor showed diverse differentiation in apocrine sweat glands and the inner and outer root sheaths of hair follicles, indicating the follicular stem cell to be the origin of this tumor.     

Accuracy of imputation of single nucleotide polymorphism marker genotypes from low‐density panels in Japanese Black cattle

Using target and reference fattened steer populations, the performance of genotype imputation using lower‐density marker panels in Japanese Black cattle was evaluated. Population imputation was performed using BEAGLE software. Genotype information for approximately 40 000 single nucleotide polymorphism (SNP) markers by Illumina BovineSNP50 BeadChip was available, and imputation accuracy was assessed based on the average concordance rates of the genotypes, varying equally spaced SNP densities, and the number of individuals in the reference population. Two additional statistics were also calculated as indicators of imputation performance. The concordance rates tended to be lower for SNPs with greater minor allele frequencies, or those located near the ends of the chromosomes. Longer autosomes yielded greater imputation accuracies than shorter ones. When SNPs were selected based on linkage disequilibrium information, relative imputation accuracy was slightly improved. When 3000 and 10 000 equally spaced SNPs were used, the imputation accuracies were greater than 90% and approximately 97%, respectively. These results indicate that combining genotyping using a lower‐density SNP chip with genotype imputation based on a population of individuals genotyped using a higher‐density SNP chip is a cost‐effective and valid approach for genomic prediction.