Evaluating the Contribution of Long-Range Transport of Heavy Metals from the Asian Continent to Their Concentrations in Sediment Cores from Lake Shinji,Western Japan     

Kenji Kusunoki  Masahiro Sakata  Yukinori Tani  Yasushi Seike  Kazuyasu Ayukawa 《Water, air, and soil pollution》2012,223(3):1151-1160

The historical trend of heavy metal pollution recorded in sediment cores from Lake Shinji, western Japan, was investigated to evaluate the contribution of increasing long-range transport of heavy metals from the Asian continent in recent years. The concentrations of Cd, Co, Cr, Cu, Ni, Pb, Sb, and Zn and lead isotope ratios were determined for sediment cores collected at two sites in the lake. Among the metals, Cd, Sb, and Zn showed markedly high concentrations since the 1970s. Moreover, a high Pb concentration and less radiogenic lead isotope ratios have been observed since the 1980s in the core from a site close to the mouth of a major river. Air masses from the Asian continent, including China, Russia, and South Korea, have less radiogenic lead isotope ratios than those from Japan. This suggests that the recent increase in Pb concentration in the sediment core is primarily due to the long-range transport of heavy metals from the Asian continent, followed by their deposition in the catchment area of the river. The concentration ratios of Pb/Cd, Pb/Sb, and Pb/Zn of the sediment around 2000 were calculated on the basis of the metal concentrations in excess of those before 1940. They were then compared with the volume-weighted annual average concentration ratios of Pb/Cd, Pb/Sb, and Pb/Zn of rain samples collected on the shore of the lake for 1999–2001. The result showed that the ratios of the former to the latter are 1.0 for Cd, 0.69 for Sb, and 0.31 for Zn. Thus, it is likely that the long-range transport of Cd and Sb from the Asian continent also contributes significantly to the recent increase in the concentrations of these metals in the sediment core from Lake Shinji. For Zn, however, the contribution from the Asian continent was evaluated to be small, suggesting the importance of local sources such as effluent discharges.  相似文献   

Differential immunolocalization between lingual antimicrobial peptide and lactoferrin in mammary gland of dairy cows     

Huang YQ  Morimoto K  Hosoda K  Yoshimura Y  Isobe N 《Veterinary immunology and immunopathology》2012,145(1-2):499-504

Lingual antimicrobial peptide (LAP), one of the β-defensins in bovines, and lactoferrin (LF) are synthesized in mammary epithelium and have bactericidal and bacteriostatic functions. However, it is not known whether they have similar expression patterns. Therefore, the present study was undertaken to compare (1) immunolocalization of LAP and LF in the mammary gland and (2) changes in concentration of these two components in milk after lipopolysaccharide (LPS) challenge. Bovine mammary tissues without LPS challenge were collected and their sections were immunostained with antibodies to LAP or LF. Milk from our previous study was collected every hour up to 12h and twice daily from d 1 to 7 after LPS challenge (the day of infusion was considered as d 0). These milk samples were measured for LAP but not LF in our previous report. Therefore, concentration of LF was measured by enzyme immunoassay in the present study. Epithelial cells of some alveoli showed immunopositive reaction for LF, but negative for LAP. Conversely, some alveoli were LAP positive in their epithelial cells but LF negative. Many alveoli had immunoreactions for neither LAP nor LF. The concentration of LAP in milk was elevated significantly at 3h after LPS infusion compared with pre-infusion values and remained at a high level until 12h. However, LF concentration in milk remained low at d 0 and increased at d 2. These results suggest that LAP and LF were mostly differentially localized in the alveolar epithelium in mammary glands. The different spatial expressions between them may be associated with their different temporal expression mechanisms.  相似文献   

Genetic succession and spatial genetic structure in a natural old growth Cryptomeria japonica forest revealed by nuclear and chloroplast microsatellite markers     

Tomokazu Takahashi  Naoki Tani  Kaoru Niiyama  Shigejiro Yoshida  Hideaki Taira  Yoshihiko Tsumura 《Forest Ecology and Management》2008

Spatial genetic structure and diversity of Cryptomeria japonica trees in old growth forest but selectively logged in approximately 300 years ago were analyzed using seven nuclear microsatellite markers and one chloroplast microsatellite marker. The individuals were sampled from a 4-ha natural forest plot (200 m × 200 m), which are consisted of three size classes including newly regenerated individuals such as regenerated individuals (REG class; stem diameter at breast height (DBH), 5–110 cm), remaining individuals (REM class; DBH ≥ 110 cm), and old stumps. Genetic diversity was similar between the three groups. These results suggest that genes from the old growth forest may have been passed on to the next generation (i.e., the current forest). DNA extraction and analysis from old stumps was partly successful and we could compare the genetic diversity between old stumps and living trees using four microsatellite loci. Patterns of spatial genetic structure detected by analyses of the nuclear and chloroplast markers differed substantially; all nuclear markers showed significant positive autocorrelation (P < 0.05) over short distances, but the chloroplast marker showed no significant autocorrelation over any distance. We concluded that Moran's I spatial autocorrelation pattern for the chloroplast microsatellite may have been influenced by the extensive pollen flow characteristic of this species, because chloroplast DNA of C. japonica is paternally inherited through pollen and is a wind-pollinated species that produces abundant pollen every few years. In contrast, Moran's I spatial autocorrelation pattern for nuclear microsatellites may reflect limited seed dispersal in gaps where the forest has regenerated and low levels of seed shadow overlap due to past logging. The average seed dispersal distance was 86.0 m at the study site and about 34.0% of the seeds were from the outside of the site, which revealed by parentage analysis. The individuals remaining after logging, and the extensive pollen flow from outside our study plot, may play important roles in maintaining the forests on this island. Gaps created by the selective logging activities appear to have been important for the regeneration of this species in the past but in the present time, natural disturbances such as typhoon and landslide are also important for gap creation.  相似文献   

Differentiation of Rhizoctonia AG-D Isolates from Turfgrass into Subgroups I and II Based on rDNA and RAPD Analyses   总被引：1，自引：0，他引：1  

Takeshi Toda  Mitsuro Hyakumachi  Haruhisa Suga  Koji Kageyama  Akemi Tanaka  Toshikazu Tani 《European journal of plant pathology / European Foundation for Plant Pathology》1999,105(9):835-846

Binucleate Rhizoctonia anastomosis group (AG) D is the cause of rhizoctonia-patch and elephant-footprint diseases of zoysiagrass, and winter-patch disease of bentgrass. Rhizoctonia AG-D is also known as the causal pathogen of other diseases such as sharp-eye-spot of cereals, foot-rot of cereals and winter-stem-rot of mat rush. Isolates of AG-D have been divided into the two subgroups AG-D (I) and AG-D (II), based on the results of cultural characteristics and pathogenicity tests. Isolates obtained from zoysiagrass exhibiting symptoms of rhizoctonia-patch disease, from bentgrass with winter-patch disease, from wheat with foot-rot disease, and from mat rush with winter-stem-rot disease were reported to belong to subgroup AG-D (I). On the other hand, isolates obtained from zoysiagrass with elephant-footprint disease were assigned to subgroup AG-D (II). To confirm the existence of these two subgroups in AG-D, the genetic structure of AG-D isolates from turfgrass and other crops was compared. RFLP analysis of the ITS region from rDNA after digestion with the restriction enzymes EcoRI, HaeIII, HhaI, HinfI, and MboI separated AG-D isolates into two groups corresponding to AG-D (I) and AG-D (II). Furthermore, other AGs except AG-Q (AGs-A, Ba, Bb, C, E, F, G, I, K, L, O, P, and R. solani AG1-IC) did not have the same patterns that were seen for the two AG-D subgroups. AG-Q isolates from bentgrass showed the same patterns as AG-D (I). The results of the RAPD analysis also revealed the existence of two groups that corresponded to AG-D (I) and AG-D (II). These analyses revealed that Rhizoctonia AG-D isolates from turfgrass could be divided into two subgroups consistent with those based on cultural characteristics and pathogenicity. In addition, isolates of foot-rot disease of wheat and isolates of winter-stem-rot disease of mat rush whose cultural characteristics were the same as those of AG-D (I) also showed similar RFLP and RAPD patterns to those of AG-D (I) isolates from turfgrass.  相似文献   

Remarkably high survival rates under dim light conditions in sutchi catfish <Emphasis Type="Italic">Pangasianodon hypophthalmus</Emphasis> larvae     

Yukinori Mukai 《Fisheries Science》2011,77(1):107-111

The sutchi catfish Pangasianodon hypophthalmus is an important species for aquaculture in Southeast Asia. However, larvae typically have low survival rates due to their predilection for cannibalism during rearing. This study investigated larval feeding behavior and rearing conditions. The former experiments were performed to elucidate the role of sensory organs in feeding, and the latter experiments examined the effect of dim light on larval rearing and survival rates. Neither lighting conditions (light and dark) nor blocking of free neuromasts by streptomycin had significant effects on feeding behavior. Therefore, the feeding behavior of sutchi catfish larvae most likely depends on chemosensing rather than visual sensing. In the later experiments, larval rearing at 0.1 l× yielded significantly higher survival rates than other lighting conditions (0.00, 1, 10, 100 l×). Survival in the 0.1 l× group was almost three times higher than in the 100 l× group. Moreover, larvae reared under 0.1 l× showed steady growth. Therefore, it is concluded that 0.1 l× is the optimum light intensity for sutchi catfish larval rearing.  相似文献   

Changes in plasma steroid levels and gene expression of pituitary gonadotropins,testicular steroidogenesis-related proteins and insulin-like growth factors during spermatogenesis of the yellowtail <Emphasis Type="Italic">Seriola quinqueradiata</Emphasis>     

Kentaro Higuchi  Koichiro Gen  Daisuke Izumida  Yukinori Kazeto  Takuro Hotta  Toshinori Takashi  Hideaki Aono  Kiyoshi Soyano 《Fisheries Science》2017,83(1):35-46

  相似文献   

Effects of Calcium Concentration in Potato Tuber Cells on the Formation of Cross-Links between Pectin Molecules by Ca<Superscript>2+</Superscript>     

Daiki Murayama  Masayuki Tani  Shinya Ikeda  Jiwan P. Palta  Samanthi W. Pelpolage  Hiroaki Yamauchi  Hiroshi Koaze 《American Journal of Potato Research》2017,94(5):524-533

The formation of cross-links between pectin molecules via Ca²⁺ in the potato tuber cell wall is a determinant factor on processing properties of potato and the quality of its products such as French fries. Thus, in this study, potato tubers varying significantly in their calcium concentrations were analyzed to investigate whether an increased absorption of calcium by a potato tuber led to an increase in the calcium concentration in the cell wall and how the calcium concentration in the cell wall influenced on the formation of cross-links between pectin molecules via Ca²⁺. Correlation analysis revealed that calcium absorbed by a potato tuber was bound to the cell wall as a water insoluble form 99 days after planting or later. Furthermore, with an increase in the calcium concentration in the cell wall, the content of chelator soluble pectin increased throughout tuber bulking and maturation stages. However, the degree of methylation was not a limiting factor in the formation of cross-links between pectin chains via Ca²⁺. Atomic force microscopy images of parenchyma cell walls prepared from mature potato tubers indicated an increase in the amount of calcium cross-linked pectin molecules with an increase in the calcium concentration in the cell wall. The present study demonstrated that the calcium concentration of the cell wall of potato tubers significantly affected the formation of cross-linkages between pectin molecules and, consequently, contributed to an enhanced formation of pectin-calcium networks in the cell wall.  相似文献   

Effect of protein hydrolysate from Antarctic krill meat on the state of water and denaturation by dehydration of lizard fish myofibrils     

Nong  ZHANG  Yasumitsu  YAMASHITA  Yukinori  NOZAKI 《Fisheries Science》2002,68(3):672-679

ABSTRACT: To utilize Antarctic krill as functional food, protein hydrolysates were prepared by enzymatic hydrolysis. Their effects on the state of water in myofibrils of lizard fish and dehydration-induced denaturation were compared with those from two species of shrimp, glucose, and sodium glutamate. Peptides are major components in hydrolysates, occupying approximately 85–93% of the total materials. The Antarctic krill protein hydrolysates stabilized the bonding of water molecules, leading to suppressed denaturation of myofibrils during the dehydration process. Similar effects were observed for shrimp protein hydrolysates. The effect of the hydrolysate was less than that by glucose and sodium glutamate.  相似文献   

Detection of specific antibodies against deflagellated Salmonella Enteritidis and S. Enteritidis FliC-specific 9kDa polypeptide     

Mizumoto N  Toyota-Hanatani Y  Sasai K  Tani H  Ekawa T  Ohta H  Baba E 《Veterinary microbiology》2004,99(2):113-120

Specific antibody levels of laying hens and young chickens experimentally infected with Salmonella Enteritidis and vaccinated farm flocks were evaluated by enzyme-linked immunosorbent assays (ELISAs) with two different antigens, deflagellated S. Enteritidis whole cell (DEWC) and S. Enteritidis FliC-specific 9kDa polypeptide (SEP9). Infected laying hens excreted S. Enteritidis throughout the experimental period, and the specific antibody titers in DEWC-ELISA, were significantly higher than the uninfected group. It suggests that this DEWC-specific antibody will serve as an effective indicator of S. Enteritidis infection, especially for non-vaccinated laying flocks. SEP9-specific antibodies were detected in spray-inoculated young chickens but not in oral-inoculated young chickens. Compared with greatly high SEP9-specific antibody levels of vaccinated farm flocks, no response was observed in orally infected hens. These results indicate that S. Enteritidis discontinues expressing SEP9 once it has crossed the intestinal barrier, and that SEP9-ELISA will serve as a valuable monitoring tool for the status of S. Enteritidis vaccination on a flockwide basis, independent of stable S. Enteritidis infections.  相似文献   

Effects of beta-thujaplicin on anti-Malassezia pachydermatis remedy for canine otitis externa     

Nakano Y  Wada M  Tani H  Sasai K  Baba E 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2005,67(12):1243-1247

The antifungal activity of beta-thujaplicin was evaluated against 51 Malassezia pachydermatis strains isolated from canine ear canals with or without otitis externa. For comparison, sensitivity tests were performed on M. pachydermatis isolates for nystatin, ketoconazole, and terbinafine HCl, all clinically available antifungal agents. The minimal inhibition concentrations over 50% of the tested isolates (MIC50) were 3.13 microg/ml for beta-thujaplicin and nystatin, 0.016 microg/ml for ketoconazole, and 1.56 microg/ml for terbinafine HCl. The antifungal effect for M. pachydermatis of beta-thujaplicin compared favorably with commercial antifungal agents. None of the 51 M. pachydermatis isolates showed resistance against any of the tested antibiotics investigated in this study. Ten representative isolates of M. pachydermatis were subcultured for 30 generations at concentrations close to the MIC levels of beta-thujaplicin, nystatin, ketoconazole, and terbinafine HCl, and examined to determine whether they had acquired resistance to each drug. As a result, M. pachydermatis was found to achieve resistance more easily for ketoconazole and terbinafine HCl than for beta-thujaplicin or nystatin. The MIC50 of beta-thujaplicin did not change during the course of subculture, and it is thought that the potential development of a resistant strain is low, even with continuous infusion for otitis externa therapy. beta-Thujaplicin is an inexpensive and safe treatment with anti-inflammatory and deodorant effects that can be recommended as an effective remedy for canine otitis externa.  相似文献