Analysis of the activity rhythm of the predatory bug Orius sauteri (Poppius) (Heteroptera: Anthocoridae) for optimizing its selective light attraction

Applied Entomology and Zoology - The minute pirate bug Orius sauteri (Poppius) (Heteroptera: Anthocoridae) is a major natural enemy of micro-pests and is expected to be an effective pest-control...     

Chimpanzees detect ant-inhabited dead branches and stems: a study of the utilization of plant–ant relationships in the Mahale Mountains, Tanzania

Chimpanzees in the Mahale Mountains of Tanzania consume several species of stem- and branch-inhabiting ants throughout the year, without tools. Those ants are cryptic species, and it was unknown how to find them constantly. There has been little research on how the chimpanzees locate these ants. In this study, I use behavioral observations of the chimpanzee predators and surveys of the ant fauna and plants across different habitats to test the hypothesis that chimpanzees use plant species as a cue to efficiently locate ant colonies in litter units (dead parts of the plant). Ants were found to be associated with live plants and with spaces within litter units which provide nesting places. Such ant–plant litter relationships were not necessarily as strong as the mutualism often observed between live plants and ants. The proportion of available litter units inhabited by ants was 20 %, and litter units of three plant species (Vernonia subligera, Dracaena usambarensis, and Senna spectabilis) were well occupied by ants in the home range of the chimpanzees. The ant-inhabited ratio in chimpanzee-foraged litter units was higher than that in the available units in the home range. Chimpanzees fed more often on Crematogaster spp. than on other resident ants and at a higher rate than expected from their occurrence in the litter units. Above three plant species were well occupied by Crematogaster sp. 3 or C. sp. 18. It is concluded that chimpanzees locate ants by selecting litter units of plant species inhabited by ants.     

Ranging behavior of Mahale chimpanzees: a 16 year study

We have analyzed the ranging patterns of the Mimikire group (M group) of chimpanzees in the Mahale Mountains National Park, Tanzania. During 16 years, the chimpanzees moved over a total area of 25.2 or 27.4 km², as estimated by the grid-cell or minimum convex polygon (MCP) methods, respectively. Annually, the M group used an average of 18.4 km², or approximately 70 %, of the total home-range area. The chimpanzees had used 80 % of their total home range after 5 years and 95 % after 11 years. M group chimpanzees were observed more than half of the time in areas that composed only 15 % of their total home range. Thus, they typically moved over limited areas, visiting other parts of their range only occasionally. On average, the chimpanzees used 7.6 km² (in MCP) per month. Mean monthly range size was smallest at the end of the rainy season and largest at the end of the dry season, but there was much variability from year to year. The chimpanzees used many of the same areas every year when Saba comorensis fruits were abundant between August and January. In contrast, the chimpanzees used several different areas of their range in June. Here range overlap between years was relatively small. Over the 16 years of the study we found that the M group reduced their use of the northern part of their range and increased their frequency of visits to the eastern mountainous side of their home range. Changes in home-range size correlated positively with the number of adult females but not with the number of adult males. This finding does not support a prediction of the male-defended territory model proposed for some East African chimpanzee unit-groups.     

The Purification and the Properties of Three Kinds of Lipases from Rhizopus delemer

The study was undertaken to clarify whether three kinds of lipases (EC 3.1.1.3) secreted from Rhizopus delemar are originally different or identical with each other. First of all, the purification of those lipases was carried out and their enzymatic properties were examined. Their properties including the stability on heat and pH, precipitabilities at a certain pH, the behaviours on a SE-Sephadex C50 column and on a Sephadex G200 column and so on were compared.

From the results, A-lipase is clearly different from the other two lipases. On the other hand, it seems that B- and C-lipases are originally identical.     

Anti-bacterial and anti-inflammatory effects of ethanol extract from Houttuynia cordata poultice

Houttuynia cordata (HC) has been commonly used as many traditional remedies in local areas of Japan. Although many pharmacological activities of HC have been reported, the mechanism underlying the effect of HC remains unknown. We conducted the interview survey in Japan to verify how HC was actually used. The interview survey revealed that HC poultice (HCP) prepared from smothering fresh leaves of HC was most frequently used for the treatment of purulent skin diseases including furuncle and carbuncle with high effectiveness. Ethanol extract of HCP (eHCP) showed anti-bacterial effects against methicillin-resistant Staphylococcus aureus (MRSA), and showed an anti-biofilm activity against MRSA. eHCP showed dose-dependent inhibition of S. aureus lipoteichoic acid (LTA)-induced interleukin-8 and CCL20 production in human keratinocyte without any cytotoxicity. These results suggest that HCP is effective for skin abscess and its underlying mechanism might be the complicated multiple activities for both bacteria and host cells.     

Wnt/beta-catenin signaling has an essential role in the initiation of limb regeneration

Anuran (frog) tadpoles and urodeles (newts and salamanders) are the only vertebrates capable of fully regenerating amputated limbs. During the early stages of regeneration these amphibians form a "blastema", a group of mesenchymal progenitor cells that specifically directs the regrowth of the limb. We report that wnt-3a is expressed in the apical epithelium of regenerating Xenopus laevis limb buds, at the appropriate time and place to play a role during blastema formation. To test whether Wnt/beta-catenin signaling is required for limb regeneration, we created transgenic X. laevis tadpoles that express Dickkopf-1 (Dkk1), a specific inhibitor of Wnt/beta-catenin signaling, under the control of a heat-shock promoter. Heat-shock immediately before limb amputation or during early blastema formation blocked limb regeneration but did not affect the development of contralateral, un-amputated limb buds. When the transgenic tadpoles were heat-shocked following the formation of a blastema, however, they retained the ability to regenerate partial hindlimb structures. Furthermore, heat-shock induced Dkk1 blocked fgf-8 but not fgf-10 expression in the blastema. We conclude that Wnt/beta-catenin signaling has an essential role during the early stages of limb regeneration, but is not absolutely required after blastema formation.     

Pathogenicity of Hantaan virus in newborn mice: genetic reassortant study demonstrating that a single amino acid change in glycoprotein G1 is related to virulence

Two Hantaan virus strains, clone 1 (cl-1), which is virulent in newborn mice, and its attenuated mutant (mu11E10), were used to examine the pathogenesis of Hantaan virus infection in a mouse model and identify virus factors relating to virulence. After subcutaneous inoculation of newborn BALB/c mice, cl-1 caused fatal disease with high viral multiplication in peripheral organs, but mu11E10 produced nonfatal infection with a low level of virus multiplication. Intracerebral inoculation of either strain caused fatal disease. Histopathological changes in the dead animals were prominent in the brain, indicating that the brain is the target organ and produces the fatal outcome. These results indicate that mu11E10 has a generally less virulent phenotype, and because of decreased multiplication in peripheral tissues, neuroinvasiveness is also decreased. An experiment with genetic reassortant viruses showed that in newborn mice the M segment is the most related to virulence and the L segment is partly related. Sequence comparison detected a single deduced amino acid change (cl-1 Ile to mu11E10 Thr) at amino acid number 515 in glycoprotein G1. One nucleotide change, but no amino acid substitution, was observed in the noncoding region of the L segment. In mouse brain microvascular endothelial cells in vitro, viruses possessing a cl-1-derived M segment grew more rapidly than viruses containing a mu11E10-derived M segment. These results suggest that the single amino acid change in the glycoprotein alters peripheral growth, which affects invasion of the central nervous system in mice.     

Effect of dietary tin deficiency on growth and mineral status in rats

To clarify the influence of dietary tin deficiency on growth and mineral status, the following two different synthetic diets were fed to male Wistar rats: group 1—a diet containing 1.99 μg tin/g; group 2—a diet containing 17 ng tin/g. The rats in group 2 showed poor growth, lowered response to sound, and alopecia, with decreased food efficiency compared with rats in group 1. The changes of mineral concentrations in tissues observed in group 2, compared with group 1, are summarized as follows: calcium concentration in lung increased; magnesium concentration in lung decreased; iron concentrations in spleen and kidney increased; iron concentration in femoral muscle decreased; zinc concentration in heart decreased; copper concentrations in heart and tibia decreased; manganese concentrations in femoral muscle and tibia decreased. These results suggest that tin may be essential for rat growth.     

Prostaglandin E1 receptor from mouse mastocytoma P-815 cells couples to 60 kDa GTP-binding protein.

The stable [3H]prostaglandin E1 (PGE1)-bound receptor, which couples to 60 kDa GTP-binding protein, from membranes of mouse mastocytoma P-815 cells has been purified and characterized. When the membranes were preincubated with [3H]PGE1 for 60 min at 37 degrees C, the dissociation of the ligand from the receptor was remarkably decreased, even in the presence of GTP gamma S. The stable [3H]PGE1-bound receptor complex was solubilized with 6% digitonin. The solubilized [3H]PGE1 receptor was eluted with [35S]GTP gamma S bindings activity from an Ultrogel AcA44 column. The fractions containing activities of both [3H]PGE1 and [35S]GTP gamma S bindings were further purified by column chromatographies on wheat germ agglutinin (WGA)-agarose and phenyl-Sepharose CL-4B. The partially purified [3H]PGE1-bound receptor was affinity-labeled with [14C]5'-p-fluorosulfonylbenzoylguanosine and a protein with a molecular mass of 60 kDa was detected. These results suggest that the ligand-bound PGE1 receptor of P-815 cells associates with a novel GTP-binding protein with a molecular mass of 60 kDa.     

Threshold-dependent BMP-mediated repression: a model for a conserved mechanism that patterns the neuroectoderm

Subdivision of the neuroectoderm into three rows of cells along the dorsal-ventral axis by neural identity genes is a highly conserved developmental process. While neural identity genes are expressed in remarkably similar patterns in vertebrates and invertebrates, previous work suggests that these patterns may be regulated by distinct upstream genetic pathways. Here we ask whether a potential conserved source of positional information provided by the BMP signaling contributes to patterning the neuroectoderm. We have addressed this question in two ways: First, we asked whether BMPs can act as bona fide morphogens to pattern the Drosophila neuroectoderm in a dose-dependent fashion, and second, we examined whether BMPs might act in a similar fashion in patterning the vertebrate neuroectoderm. In this study, we show that graded BMP signaling participates in organizing the neural axis in Drosophila by repressing expression of neural identity genes in a threshold-dependent fashion. We also provide evidence for a similar organizing activity of BMP signaling in chick neural plate explants, which may operate by the same double negative mechanism that acts earlier during neural induction. We propose that BMPs played an ancestral role in patterning the metazoan neuroectoderm by threshold-dependent repression of neural identity genes.