Chiral response of Oryzeae and Paniceae plants in alpha-methylbenzyl-3-p-tolyl urea agar medium

The results presented here support the hypothesis that plants of the tribe Oryzeae respond enantioselectively and homogeneously to optically active 1-alpha-methylbenzyl-3-p-tolylurea (MBTU) in root growth inhibition, in contrast to Echinochloa species. The Oryzeae plants tested in this study belong to different genera (Oryza, Leersia, Chikusichloa and Zizania), to different species (O sativa, O glaberrima, O alta, O coarctata, O latifolia, O minuta, O rufipogon), to various ecospecies of Oryza (japonica, indica, japonica x indica, javanica) and to different levels of evolution [cultivated rice (O sativa and O glaberrima) and ancestral wild rice species]. In spite of their different phylogenic status and diverse sensitivity, the root growth of all members of the genus Oryza was inhibited more by R-MBTU than by S-MBTU. Zizania palustris, Z latifolia, Leersia oryzoides and Chikusichloa aquatica belonging to the tribe Oryzeae exhibited similar chiral recognition to the Oryza plants, suggesting that Oryzeae have a common chiral recognition mechanism in their response to optically active MBTUs. In contrast, Echinochloa plants (E crus-galli (L) Beauv var crus-galli and E colonum (L) Link), belonging into subfamily Panicoideae tribe Paniceae, responded in a different way, where their root growth was more sensitive to S-MBTU than to the antipodal R-MBTU. A reverse chiral response between the tribe Oryzeae and the genus Echinochloa was clearly indicated in this study. This diverse response may be relevant to Gramineae classification.     

Evaluation on the pathogenicity of Erysipelothrix tonsillarum for pigs by immunosuppression with cyclophosphamide or dexamethasone

The pathogenicity of Erysipelothrix tonsillarum was evaluated in pigs immunosuppressed with cyclophosphamide (CY) or dexamethasone (DM). Animals were treated with 15 mg/kg CY (n = 8, five injections), 1 mg/kg DM (n = 8, nine injections) or left untreated (n = 8). On the fifth day after the beginning of drug treatments, swine were inoculated with one of two E. tonsillarum serovar 7 strains (approximately 10⁶ CFU per pig). In the CY-treated group, both circulating neutrophil and lymphocyte counts decreased, whereas in the DM-treated group, lymphocyte counts decreased but neutrophil counts increased. During the observation period, none of the CY- or DM-treated pigs developed clinical signs or gross lesions, as well as non-treated pigs. Growth agglutination antibody titres in all pigs remained unchanged. Our findings indicate that E. tonsillarum strains are avirulent for swine, regardless of immune status.     

Supplementary immunocytochemistry of hepatocyte growth factor production in activated macrophages early in muscle regeneration

Regenerative intramuscular motor‐innervation is thought to reside in the spatiotemporal expression of axon‐guidance molecules. Our previous studies showed that resident myogenic stem cells, satellite cells, up‐regulate a secreted neural‐chemorepellent semaphorin 3A (Sema3A) during the early‐differentiation period, in response to hepatocyte growth factor (HGF) elevated in injured muscle. However, a paracrine source of the HGF release is still unknown. Very recently, we proposed a possible contribution of anti‐inflammatory macrophages (CD206‐positive M2) by showing that M2 cells infiltrate predominantly at the early‐differentiation phase (3–5 days post‐injury) and produce/secrete large amounts of HGF. However, in understanding this concept there still remains a critical need to examine if phagocytotic pro‐inflammatory macrophages (CD86‐positive M1), another activated‐phenotype still present at the early‐differentiation phase concerned, produce HGF upon muscle injury. The current immunocytochemical study demonstrated that the HGF expression is negative for M1 prepared from cardiotoxin‐injured Tibialis anterior muscle at day 5, in contrast to the intense fluorescent‐signal of M2 served as a positive control. This supplementary result advances our understanding of a spatiotemporal burst of HGF secretion from M2 populations (not M1) to impact Sema3A expression, which ensures a coordinated delay in attachment of motoneuron terminals onto damaged and generating fibers during the early phase of muscle regeneration.     

Construction of a linkage map based on retrotransposon insertion polymorphisms in sweetpotato via high-throughput sequencing

Sweetpotato (Ipomoea batatas L.) is an outcrossing hexaploid species with a large number of chromosomes (2n = 6x = 90). Although sweetpotato is one of the world’s most important crops, genetic analysis of the species has been hindered by its genetic complexity combined with the lack of a whole genome sequence. In the present study, we constructed a genetic linkage map based on retrotransposon insertion polymorphisms using a mapping population derived from a cross between ‘Purple Sweet Lord’ (PSL) and ‘90IDN-47’ cultivars. High-throughput sequencing and subsequent data analyses identified many Rtsp-1 retrotransposon insertion sites, and their allele dosages (simplex, duplex, triplex, or double-simplex) were determined based on segregation ratios in the mapping population. Using a pseudo-testcross strategy, 43 and 47 linkage groups were generated for PSL and 90IDN-47, respectively. Interestingly, most of these insertions (~90%) were present in a simplex manner, indicating their utility for linkage map construction in polyploid species. Additionally, our approach led to savings of time and labor for genotyping. Although the number of markers herein was insufficient for map-based cloning, our trial analysis exhibited the utility of retrotransposon-based markers for linkage map construction in sweetpotato.     

Ingestion of proteoglycan fraction from shark cartilage increases serum inhibitory activity against matrix metalloproteinase-9 and suppresses development of N-nitrosobis(2-oxopropyl)amine-induced pancreatic duct carcinogenesis in hamster

A water extract of shark cartilage was fractionated into acidic and basic fractions by preparative isoelectric focusing on the basis of the amphoteric nature of samples. The acidic fraction was further fractionated into ethanol-soluble and -precipitate fractions. After the carcinogenesis treatment using N-nitrosobis(2-oxopropyl)amine, hamsters received a diet containing each fraction or purified chondroichin sulfate to give 0.4% (w/w) for 50 days. Only administration of the acidic ethanol-precipitate-fraction-containing diet significantly increased serum inhibitory activity against matrix metalloproteinase (MMP)-9 and reduced the number of adenocarcinomas in the pancreatic duct. The active fraction predominantly consisted of chondroichin sulfate-containing proteoglycan. However, the purified chondroichin sulfate had no significant activity. These results suggest that the protein moiety of the proteoglycan might be involved in the increase of serum inhibitory activity against MMP-9 and suppression of pancreatic carcinogenesis in hamster.     

Development and evaluation of event-specific qualitative PCR methods for genetically modified Bt10 maize

In 2005 it was reported that the genetically modified (GM) maize strain or "event" called Bt10 had been distributed inadvertently in the United States over the previous 4 years. In order to ensure that grain for food and feed production did not contain trace amounts of Bt10 maize and complied with the applicable regulation, highly sensitive and specific detection of Bt10 maize was required. Accordingly, we developed a novel qualitative PCR system for specific detection of Bt10 maize. Moreover, we amply evaluated the performance characteristics of two PCR systems, our own and the one provided by the developer of Bt10, Syngenta Co. Ltd. It was confirmed that both of the qualitative PCR systems can specifically detect Bt10 maize, and the results of a single-laboratory examination suggested that the limit of detection was approximately less than 0.05% for both methods. To evaluate the reproducibility of the methods, we organized an interlaboratory study with the participation of 6 laboratories and analysis of 240 blind test samples. In this paper, we report, for the first time, the statistical analysis of the qualitative PCR data obtained from the interlaboratory study. The results of this analysis also revealed that there was no significant difference in the sensitivity between the two aforementioned methods and that the limit of detection of both the methods was less than 0.05%. Thus, we conclude that both of the methods are equally suitable for correct identification and sensitive detection of the unapproved GM maize Bt10 event in test samples.