Successful selection of an infection‐protective anti‐Staphylococcus aureus monoclonal antibody and its protective activity in murine infection models

Recent clinical trials to develop anti‐methicillin‐resistant Staphylococcus aureus (MRSA) therapeutic antibodies have met unsuccessful sequels. To develop more effective antibodies against MRSA infection, a panel of mAbs against S. aureus cell wall was generated and then screened for the most protective mAb in mouse infection models. Twenty‐two anti‐S. aureus IgG mAbs were obtained from mice that had been immunized with alkali‐processed, deacetylated cell walls of S. aureus. One of these mAbs, ZBIA5H, exhibited life‐saving effects in mouse models of sepsis caused by community‐acquired MRSA strain MW2 and vancomycin‐resistant S. aureus strain VRS1. It also had a curative effect in a MW2‐caused pneumonia model. Curiously, the target of ZBIA5H was considered to be a conformational epitope of either the 1,4‐β‐linkage between N‐acetylmuramic acid and N‐acetyl‐D‐glucosamine or the peptidoglycan per se. Reactivity of ZBIA5H to S. aureus whole cells or purified peptidoglycan was weaker than that of most of the other mAbs generated in this study. However, the latter mAbs did not have the protective activities against S. aureus that ZBIA5H did. These data indicate that the epitopes that trigger production of high‐yield and/or high‐affinity antibodies may not be the most suitable epitopes for developing anti‐infective antibodies. ZBIA5H or its humanized form may find a future clinical application, and its target epitope may be used for the production of vaccines against S. aureus infection.     

Chromosomal study of lettuce and its allied species (Lactuca spp., Asteraceae) by means of karyotype analysis and fluorescence in situ hybridization

In this study, in addition to the karyotype analysis, the chromosomal distributions of 5 S and 18 S rDNAs, and the Arabidopsis-type (T3AG3) telomeric sequences were detected by means of fluorescence in situ hybridization (FISH) to promote the information of chromosomal organization and evolution in the cultivated lettuce and its wild relatives, L. sativa, L. serriola, L. saligna and L. virosa. The karyotype analysis revealed the dissimilarity between L. virosa and the remaining species. In all four Lactuca species studied, one 5 S rDNA and two 18 S rDNA loci were detected. The simultaneous FISH of 5 S and 18 S rDNAs revealed that both rDNA loci of L. sativa, L. serriola and L. saligna were identical, however, that of L. virosa was different from the other species. These analyses indicate the closer relationships between L. sativa/L. serriola and L. saligna rather than L. virosa. Arabidopsis-type telomeric sequences were detected at both ends of their chromatids of all chromosomes not in the other regions. This observation suggests the lack of telomere-mediated chromosomal rearrangements among the Lactuca chromosomes.     

Endotoxin and cytokines in patients with gastrointestinal tract perforation

Plasma levels of endotoxin and various cytokines were assessed in 70 patients with gastrointestinal tract perforation. Sepsis developed in 29 of them, and eight of these (27.6%) had on admission endotoxin levels higher than 9.8 pg ml(-1). The clinical outcome correlated with the level of tumour necrosis factor alpha (TNFalpha), rather than with the endotoxin level. The high interleukin 6 (IL-6) level was shown in septic patients and no correlation was observed between the IL-6 level and the clinical outcome. Plasma TNFalpha levels tended to change independently from endotoxin levels, suggesting that TNFalpha may have been locally produced in inflammatory lesions.     

Temporary blockade of contractility during reperfusion elicits a cardioprotective effect of the p38 MAP kinase inhibitor SB-203580

p38 MAP kinase activation is known to be deleterious not only to mitochondria but also to contractile function. Therefore, p38 MAP kinase inhibition therapy represents a promising approach in preventing reperfusion injury in the heart. However, reversal of p38 MAP kinase-mediated contractile dysfunction may disrupt the fragile sarcolemma of ischemic-reperfused myocytes. We, therefore, hypothesized that the beneficial effect of p38 MAP kinase inhibition during reperfusion can be enhanced when contractility is simultaneously blocked. Isolated and perfused rat hearts were paced at 330 rpm and subjected to 20 min of ischemia followed by reperfusion. p38 MAP kinase was activated after ischemia and early during reperfusion (<30 min). Treatment with the p38 MAP kinase inhibitor SB-203580 (10 microM) for 30 min during reperfusion, but not the c-Jun NH(2)-terminal kinase inhibitor SP-600125 (10 microM), improved contractility but increased creatine kinase release and infarct size. Cotreatment with SB-203580 and the contractile blocker 2,3-butanedione monoxime (BDM, 20 mM) or the ultra-short-acting beta-blocker esmorol (0.15 mM) for the first 30 min during reperfusion significantly reduced creatine kinase release and infarct size. In vitro mitochondrial ATP generation and myocardial ATP content were significantly increased in the heart cotreated with SB-203580 and BDM during reperfusion. Dystrophin was translocated from the sarcolemma during ischemia and reperfusion. SB-203580 increased accumulation of Evans blue dye in myocytes depleted of sarcolemmal dystrophin during reperfusion, whereas cotreatment with BDM facilitated restoration of sarcolemmal dystrophin and mitigated sarcolemmal damage after withdrawal of BDM. These results suggest that treatment with SB-203580 during reperfusion aggravates myocyte necrosis but concomitant blockade of contractile force unmasks cardioprotective effects of SB-203580.     

Phylogenetic significance of stylar features in genus Vicia (Leguminosae): an analysis with molecular phylogeny

Tribe Fabeae consists of five genera, Lathyrus (160 spp.), Lens (4–6 spp.), Pisum (2–3 spp.), Vavilovia (monotypic), and Vicia (160 spp.), and shows a diversity in stylar features. At least six different stylar types are known in the tribe. In order to reclassify the tribe at the rank of genus, we tried to discover apomorphies in stylar features using a molecular phylogenetic study. We surveyed internal transcribed spacer (ITS) sequences of nuclear ribosomal DNA of representative species, selected from each group having different types of styles in the tribe. We paid particular attention in sampling to members of Vicia section Vicilla, as stylar features are heterogeneous within this section. Consequently, our sample set included 15 species of section Vicilla, 23 species of other Fabeae, and two species of Trifolieae, which were used as a sister group of Fabeae. Based on our analysis, we found that a laterally compressed style and an abaxially tufted hairy style would be advanced against a dorsiventrally compressed style and an evenly hairy style, respectively, in genus Vicia. The species group, which shares the latter apomorphy, is composed of 56 species and was dispersed into 11 sections of two subgenera in the recent system of genus Vicia. We consider future revision of Fabeae should treat this species group as a single higher taxon.     

Oocyte mitochondria: Strategies to improve embryogenesis

Mitochondria play a central role to provide ATP for fertilization and preimplantation embryo development in the ooplasm. The mitochondrial dysfunction of oocyte has been proposed as one of the causes of high levels of developmental retardation and arrest that occur in preimplantation embryos generated using Assisted Reproductive Technology. Cytoplasmic transfer (CT) from a donor to a recipient oocyte has been applied to infertility due to dysfunctional ooplasm, with resulting pregnancies and births. However, neither the efficacy nor safety of this procedure has been appropriately investigated. In order to improve embryogenesis, we observed the mitochondrial distribution in ooplasma under the several conditions using mitochondrial GFP-transgenic mice (mtGFP-tg mice) in which the mitochondria are visualized by GFP. In this report, we will present our research about the mitochondrial distribution in ooplasm during early embryogenesis and the fate of injected donor mitochondria after CT using mtGFP-tg mice. The mitochondria in ooplasm from the germinal vesicle stage to the morula stage were accumulated in the perinuclear region. The mitochondria of the mtGFP-tg mouse oocyte transferred into the wild type mouse embryo could be observed until the blastocysts stage, suggesting that the mtGFP-tg mice oocyte is very useful for visual observation of the mitochondrial distribution in the oocyte, and that the aberrant early developmental competences due to the oocyte mitochondrial dysfunction may be overcome by transferring the "normal" mitochondria.     

Synthesis of anilino-monoindolylmaleimides as potent and selective PKCbeta inhibitors

We report herein synthesis of PKCbeta-selective inhibitors possessing the novel pharmacophore of anilino-monoindolylmaleimide. Several compounds of this series exhibited IC50's as low as 50 nM against human PKCbeta2. One of the most potent compounds, 6l, inhibited PKCbeta1 and PKCbeta2 with IC50 of 21 and 5 nM, respectively, and exhibited selectivity of more than 60-fold in favor of PKCbeta2 relative to other PKC isozymes (PKCalpha, PKCgamma, and PKCepsilon).     

Development of flight performance in the brown booby

How do birds acquire flight skills after fledging? This issue is important, as it is closely related to variation in the duration of offspring care, the causes of which remain unknown. In this study, we raised hatchling brown boobies, Sula leucogaster, and attached an acceleration data logger to each bird at fledging to record its movements. This allowed us to quantify precisely the time spent flapping, gliding and resting. The duration of foraging trips and proportion of time spent gliding during flight increased with the number of days since fledging, whereas the proportion of time spent in flight decreased. This indicates that brown boobies gradually acquire efficient flight skills during the post-fledging period, which might be the proximate cause of the long postfledging care period in this species. To the authors' knowledge, this is the first study to record precisely the ontogeny of flight behaviour in birds.     

Signification of the sexualizing substance produced by the sexualized planarians

Asexual worms of an exclusively fissiparous strain (the OH strain) of the planarian Dugesia ryukyuensis keep developing hermaphroditic reproductive organs and eventually undergo sexual reproduction instead of asexual reproduction, namely fission, if they are fed with sexually mature worms of an exclusively oviparous planarian, Bdellocephala brunnea, suggesting that the sexually mature worms has a sexualizing substance(s). The fully sexualized worms no longer need the feeding on sexual worms to maintain the sexuality. Here, we demonstrate that the sexualized worms produce enough of their own sexualizing substance similar to that contained in B. brunnea. In case of surgical ablation of the sexualized worms, the fragments with sexual organs regenerate to become sexual, while those without sexual organs, namely head fragments, regenerate to return to the asexual state. The asexual regenerants from the sexualized worms are also fully sexualized by being fed with B. brunnea. Additionally, it was reported that head region in sexually mature worms lacks the putative sexualizing substance necessary for complete sexualization (Sakurai, 1981). These results suggest that the fragments without sexual organ lack enough of an amount of the putative sexualizing substance and the sexuality is maintained by the sexualizing substance contained in the sexualized worms.