1NM-PP1 treatment of mice infected with Toxoplasma gondii

Bumped kinase inhibitors (BKIs) target analog-sensitive kinases, which the genomes of mammals rarely encode. Previously, we demonstrated that a BKI effectively suppressed the in vitro replication of Toxoplasma gondii, the causative pathogen of toxoplasmosis, by targeting T. gondii calcium-dependent protein kinase 1 (TgCDPK1) (Eukaryotic Cell, 9: 667-670). Here, we examined whether the BKI 1NM-PP1 reduced parasite replication in vivo. A high dose of 1NM-PP1, by intraperitoneal injection, just before the parasite inoculation effectively reduced the parasite load in the brains, livers, and lungs of T. gondii-infected mice, however, a low dose of 1NM-PP1 with oral administration didn't change the survival rates of infected mice.     

Developmental ability of vitrified mouse oocytes expressing water channels

Previously, we showed that the exogenous expression of aquaporin 3 (AQP3), an aquaglyceroporin, improved the tolerance of mouse oocytes to vitrification with a glycerol-based solution. In the present study, we examined conditions suitable for the expression of AQP3 and the ability of vitrified oocytes to develop in vitro and in vivo after fertilization. After only partial remove of cumulus cells, immature mouse oocytes (germinal vesicle stage) were injected with 5, 10 or 20 pg of AQP3 cRNA and cultured for 12 h for maturation. When matured oocytes were vitrified with a glycerol-based solution, 57-61% survived regardless of the amount of cRNA injected (5-20 pg). By contrast, no oocytes injected with water (control) survived. When the zona pellucida was removed from the vitrified oocytes and the oocytes were then fertilized in vitro and cultured, the proportions that were fertilized and developed into blastocysts were higher when the amount of cRNA injected was 5 pg than 10-20 pg. When 16 blastocysts were transferred to a pseudopregnant mouse, 5 developed to term, demonstrating that oocytes vitrified after injection of AQP3 cRNA retained the ability to develop to term. The water-permeability of cRNA-injected oocytes was higher than that of control oocytes from the maturing stage to the 1-cell zygote stage, whereas glycerol-permeability was higher only at metaphase II. This indicates that AQP3 was expressed for a relatively short period of time. These results suggest that the transient expression of water/cryoprotectant channels is effective for cryopreserving cells that have low membrane-permeability, such as mammalian oocytes.     

Complete sequence analysis of two cryptic plasmids from Bifidobacterium kashiwanohense JCM 15439 (type strain) isolated from healthy infant feces

Bifidobacterial plasmids reported so far are derived from a limited number of strains and plasmids of bifidobacterial type strains isolated from humans are unknown. We found that Bifidobacterium kashiwanohense JCM 15439 (type strain) isolated from a healthy infant contained two cryptic plasmids, designated pBBKW‐1 and pBBKW‐2. We determined and analyzed the complete sequences of both plasmids. pBBKW‐1 (7716 bp) was predicted to replicate by a rolling‐circle mechanism and encode six protein‐coding genes, two of which are putative replication proteins. pBBKW‐1 seems to be a cointegrate plasmid containing two copies of the plasmid pMG1 from Bifidobacterium longum. pBBKW‐2 (2920 bp) was predicted to encode six protein‐coding genes and be a theta‐type replicating plasmid, which has been reported to be more stable than a rolling circle‐type replicating plasmid frequently found in bifidobacteria. Our finding will provide new insights into safe recombinant plasmid constructions for humans.     

Siphonaxanthin,a Green Algal Carotenoid,as a Novel Functional Compound

Siphonaxanthin is a specific keto-carotenoid in green algae whose bio-functional properties are yet to be identified. This review focuses on siphonaxanthin as a bioactive compound and outlines the evidence associated with functionality. Siphonaxanthin has been reported to potently inhibit the viability of human leukemia HL-60 cells via induction of apoptosis. In comparison with fucoxanthin, siphonaxanthin markedly reduced cell viability as early as 6 h after treatment. The cellular uptake of siphonaxanthin was 2-fold higher than fucoxanthin. It has been proposed that siphonaxanthin possesses significant anti-angiogenic activity in studies using human umbilical vein endothelial cells and rat aortic ring. The results of these studies suggested that the anti-angiogenic effect of siphonaxanthin is due to the down-regulation of signal transduction by fibroblast growth factor receptor-1 in vascular endothelial cells. Siphonaxanthin also exhibited inhibitory effects on antigen-induced degranulation of mast cells. These findings open up new avenues for future research on siphonaxanthin as a bioactive compound, and additional investigation, especially in vivo studies, are required to validate these findings. In addition, further studies are needed to determine its bioavailability and metabolic fate.     

The first success of glass eel production in the world: basic biology on fish reproduction advances new applied technology in aquaculture

The eel has long been esteemed as an important food fish in the world, especially in Japan, and has been used as an experimental fish for many fields of fish physiology. However, the decreases in eel resources have been a serious concern in recent years. The catches of glass eels as seedlings for aquaculture have shown a long-term decrease in both Europe and East Asia. To increase eel resources, the development of techniques for artificial induction of maturation and spawning and rearing their larvae have been eagerly desired. Recent progress of reproductive physiology of fish, especially mechanisms of oocyte maturation and ovulation in female and of spermatozoa maturation in male, facilitate to establish techniques for hormonal induction of maturation and spawning in sexually immature eels. With persistent effort to development of rearing techniques of larvae, we have first succeeded to produce glass eel. These applied techniques are may contribute to understand the basic reproductive physiology of the eel.     

Characterization of methicillin-resistant Staphylococcus aureus isolated from retail raw chicken meat in Japan

Two isolates of mecA-positive methicillin-resistant Staphylococcus aureus (MRSA) from retail raw chicken meat were characterized by phenotypic and genotypic methods. One isolate showed the human biovar, coagulase type III, phage group I * III, the lack of production of enterotoxins and TSST-1, and resistance to PCG/ABPC/EM/GM/KM. The other isolate showed the human biovar, coagulase type III, phage group III, production of enterotoxin C and TSST-1, and resistance to PCG/ABPC/CEZ. The biotyping results indicate that the two isolates showed characteristics of human S. aureus. They also harbored SCCmec type IV, which has prevalently been found in community-acquired MRSA isolates. This paper is the first publication regarding MRSA isolates from raw chicken meat in Japan.     

Influence of different methods of collection from the canine epididymides on post-thaw caudal epididymal sperm quality

Canine epididymal sperm was collected from the cauda epididymis using 2 different methods (flushing and mincing) to compare the qualities (the percentage of progressively motile, viable, morphologically abnormal, immature and intact acrosomes) before and after freezing and thawing. No significant difference was noted in the quality of the cauda epididymal sperm immediately after collection and after freezing-thawing between the collection methods, although the mean levels of sperm quality with the flushing method were slightly better than that of the mincing method. The flushing method is simple and free of blood contamination, although the vas deferens was too small to be perfused in only 1 dog, and our results suggest that the flushing method is preferable to the mincing method for collecting sperm from the canine cauda epididymis.     

Fenprostalene-induced abortion in bitches

A long-acting prostaglandin F(2alpha) analogue, fenprostalene, was subcutaneously administered singly at doses of 5, 10, 25, 50, 100 or 150 microg on day 25 after ovulation during pregnancy in bitches (n=4 for each dosage), and maintenance of pregnancy, changes in plasma progesterone concentration, interval between the treatment and subsequent estrus and conception rate at that estrus were studied. Abortion was associated with a decrease in the plasma progesterone concentration below about 2 ng/ml, and the abortifacient effect was dose-dependent. Administration of 50 microg or more of fenprostalene induced abortion in all dogs 3 to 13 days after the treatment. The interval between administration and subsequent estrus was markedly shorter in the aborted bitches than in the non-aborted ones (P<0.01). The conception rate at the estrus in the aborted dogs was 50%, whereas all of the bitches who had not aborted became pregnant. The results indicate that a single administration of fenprostalene could induce abortion during mid-pregnancy in bitches, and the subsequent estrus may come early with a low conception rate.     

Transcriptional profiling of inflammatory cytokine genes in African buffaloes (Syncerus caffer) infected with Theileria parva

Theileria parva (T. parva) causes East Coast fever (ECF), which is of huge economic importance to Eastern and Southern African countries. In a previous bovine model, inflammatory cytokines were closely associated with disease progression in animals experimentally infected with T. parva. The African Cape buffalo (Syncerus caffer), the natural reservoir for T. parva, is completely resistant to ECF despite a persistently high parasitaemia following infection with T. parva. Characterizing basic immunological interactions in the host is critical to understanding the mechanism underlying disease resistance in the African Cape buffalo. In this study, the expression level of several cytokines was analyzed in T. parva-infected buffaloes. There were no significant differences in the expression profiles of inflammatory cytokines between the infected and uninfected animals despite a remarkably high parasitaemia in the former. However, the expression level of IL-10 was significantly upregulated in the infected animals. These results indicate a correlation between diminished inflammatory cytokines response and disease resistance in the buffalo.