Diversity and composition of flower-visiting insects and related factors in three fruit tree species

Animal-mediated pollination is an essential ecosystem service for the production of many fruit trees. To reveal the community composition of flower-visiting wild insects which potentially contribute to fruit production and to examine the effects of geographic location, local meteorological conditions and locally introduced domesticated pollinators on them, we investigated the community composition of insects visiting the flowers (hereafter, "visitors") of apple, Japanese pear and Oriental persimmon for 1‒3 years at 20 sites around Japan. While most of the variation (82%) of the community composition was explained by tree species with a slight contribution by geographic distance (2%), maximum temperature and tree species contributed 62% and 41% of the variation in total abundance of the visitors, respectively. Though the dominant families of the visitors varied spatiotemporally, the community composition of the visitors of apple and Japanese pear clearly differed from that of Oriental persimmon. While Andrenidae and Syrphidae together accounted for 46%‒64% of the visitors of apple and Japanese pear, Apidae represented 57% of the visitors of Oriental persimmon. The taxonomic richness, diversity and evenness of the visitors were best predicted by locally introduced domesticated pollinators and local meteorological conditions of wind speed and maximum temperature. Amongst these selected factors, locally introduced domesticated pollinators could have the largest impact. It seemed to be strongly related to the reduction of taxonomic richness, diversity and evenness of the visitors, accounting for 41‒89% of the variation. Results suggested that the community composition and total abundance of potential pollinators were predominantly determined by tree species and temperature, but locally introduced domesticated pollinators could have a determinantal pressure on the taxonomic diversity of the community.

P2725Transthyretin cardiac amyloidosis in heart failure with preserved ejection fraction: Imaging by Tc-99m bone scan

Background

Heart failure with preserved ejection fraction (HFpEF) is a heterogeneous clinical syndrome with multiple underlying causes. Transthyretin amyloidosis (ATTR) is an underdiagnosed cause of HFpEF. Extraosseous uptake, in particular, myocardial uptake, was observed in a number of ATTR patients examined with the bone scan tracers.

Objectives

We sought to determine the prevalence of ATTR as detected by the bone scan among the patients admitted due to HFpEF.

Methods

We screened all consecutive patients ≥60 years old admitted due to HFpEF (left ventricular ejection fraction ≥50%). All eligible patients were offered an echocardiogram and a bone scan (a 99mTc-DPD/MDP/HMDP scintigraphy). Echocardiographic and clinical variables were gathered in all the subjects. The intensity of the myocardial uptake was graded according to a visual scale ranging from 0 to 3 points, in which the absence of uptake was assigned a score of 0 points; uptake less than that of bone (referred to as the adjacent rib), 1 point; uptake similar to that of bone, 2 points; and uptake greater than that of bone, 3 points. The distribution of the uptake in myocardium was defined as focal uptake, diffuse uptake, uptake in a ventricular wall segment, diffuse ventricular uptake, or diffuse biventricular uptake.

Results

The study included 62 HFpEF patients (52% women, 73±9 years). The bone scintigraphic analysis revealed relatively intense myocardial uptake in 7 of 62 patients (11.2%). 7 patients had intense Tc-99m uptake (score of 2–3) in the cardiac region, showing deposition in both right and left ventricles in every case. Patients with amyloid deposition were older (78±6 vs. 70±12 years, p<0.05), had a lower systolic blood pressure (118±23 vs. 148±28 mmHg, p<0.05), and left ventricular ejection fraction (52±11 vs. 58±6%, p<0.05). Both groups had at least moderate left ventricular hypertrophy and abnormal global longitudinal strain with no significant difference between groups. In 6 all the cases, the final diagnosis of amyloidosis was based on the results of abdominal fat aspiration biopsy.

Conclusion

ATTR is an underdiagnosed disease that accounts for a significant number (11.2%) of HFpEF cases. These findings create an opportunity for further investigation in the targeted therapy of patients with HFpEF.

Ecological risks of insecticide contamination in water and sediment around off-farm irrigated rice paddy fields

The ecological impacts of insecticides in aquatic areas around agricultural lands have long been ignored in the regulation scheme of pesticides in Japan. Upon the scheme, the predicted concentration of an insecticide in the main stream of a river is the only parameter considered, suggesting that the ecological impacts of insecticides on local biodiversity around agricultural fields are underestimated. To fill this knowledge gap, we measured insecticide concentrations in surface water and sediment in aquatic areas around paddy fields at 35 locations across Japan. Among the 18 insecticides considered, 15 were detected somewhere in Japan and their concentrations were generally higher in the southwestern region in Japan (e.g. Hiroshima, Saga, or Kagoshima prefectures). Most insecticides were accumulated at higher concentrations in sediment than in surface water, consistent with previous studies. We also detected insecticides applied to nursery boxes at high concentrations in surrounding aquatic areas, although such application is generally considered to have low environmental risks. In addition, derivatives of fipronil, which have similar toxicity as that of fipronil, were often detected in sediment at higher concentrations than fipronil itself. Concentrations of dinotefuran in water at two sampling points were higher than the 5% hazardous concentration (HC5), indicating a possibility of a risk of acute toxicity to aquatic organisms. Our findings indicate that ecological risk assessments of insecticides and their derivatives should be expanded to include concentrations in sediment and water around paddy fields as well.

An Efficient Method for Monitoring Predatory Minute Pirate Bugs Orius spp. (Hemiptera: Anthocoridae) Populations Using Blue-Colored Sticky Traps

Minute pirate bugs of genus Orius (Wolff) are known important generalist predators of microinvertebrate pests and are therefore useful in many agricultural contexts. Effective sampling methods are thus of great importance to monitor Orius spp. populations. Sticky traps are one such sampling method; however, trap color must be carefully selected for the target insect species. In this study, we examined the most suitable sticky trap color (i.e., white, blue, or yellow) to capture Orius spp. individuals in eggplant Solanum melongena (Linnaeus) (Solanales: Solanaceae), Italian ryegrass Lolium multiflorum (Lamarck) (Poales: Poaceae), soybean Glycine max (Linnaeus) (Fabales: Fabaceae), and white clover Trifolium repens (Linnaeus) (Fabales: Fabaceae) fields. More Orius spp. adults were caught on blue and white traps than on yellow traps. The white traps also caught other insects, which hampered the counting of Orius spp. individuals and, therefore, reduced trapping efficiency. In addition, seasonal prevalence investigations showed that blue sticky traps had similar patterns to those of field observations. Thus, as the blue sticky trap can avoid capturing nontarget insects, we concluded that blue was the most suitable trap color for monitoring Orius spp. In addition, because blue sticky traps are more efficient and less-labor intensive, they can be useful as an alternative to field observations.

Characterization of Venom and Oviduct Components of Parasitoid Wasp Asobara japonica

During natural parasitization, Asobara japonica wasps introduce lateral oviduct (LO) components into their Drosophila hosts soon after the venom injection to neutralize its strong toxicity; otherwise, the host will die. Although the orchestrated relationship between the venom and LO components necessary for successful parasitism has attracted the attention of many researchers in this field, the molecular natures of both factors remain ambiguous. We here showed that precipitation of the venom components by ultracentrifugation yielded a toxic fraction that was inactivated by ultraviolet light irradiation, boiling, and sonication, suggesting that it is a virus-like entity. Morphological observation of the precipitate after ultracentrifugation showed small spherical heterogeneous virus-like particles 20-40 nm in diameter. The venom's detrimental effect on D. melanogaster larvae was not directly neutralized by the LO components but blocked by a hemolymphal neutralizing factor activated by the LO factor. Furthermore, we found that A. japonica venom and LO components acted similarly on the larvae of the common cutworm Spodoptera litura: the venom injection caused mortality but coinjection of the LO factor protected S. litura larvae from the venom's toxicity. In contrast, D. ficusphila and D. bipectinata, which are closely related to D. melanogaster but non-habitual host species of A. japonica, were not negatively affected by A. japonica venom due to an intrinsic neutralizing activity in their hemolymph, indicating that these species must have acquired a neutralizer of A. japonica venom during evolution. These results give new insights into the characteristics of both the venom and LO components: A. japonica females have utilized the virus-like toxic venom factor to exploit a wider range of host species after the evolutionary process enabled them to use the LO factor for activation of the host hemolymph neutralizer precursor, although the non-habitual host Drosophila species possess an active intrinsic neutralizer in their hemolymph.

Bacteria Endosymbiont, Wolbachia, Promotes Parasitism of Parasitoid Wasp Asobara japonica

Wolbachia is the most widespread endosymbiotic bacterium that manipulates reproduction of its arthropod hosts to enhance its own spread throughout host populations. Infection with Wolbachia causes complete parthenogenetic reproduction in many Hymenoptera, producing only female offspring. The mechanism of such reproductive manipulation by Wolbachia has been extensively studied. However, the effects of Wolbachia symbiosis on behavioral traits of the hosts are scarcely investigated. The parasitoid wasp Asobara japonica is an ideal insect to investigate this because symbiotic and aposymbiotic strains are available: Wolbachia-infected Tokyo (TK) and noninfected Iriomote (IR) strains originally collected on the main island and southwest islands of Japan, respectively. We compared the oviposition behaviors of the two strains and found that TK strain females parasitized Drosophila melanogaster larvae more actively than the IR strain, especially during the first two days after eclosion. Removing Wolbachia from the TK strain wasps by treatment with tetracycline or rifampicin decreased their parasitism activity to the level of the IR strain. Morphological and behavioral analyses of both strain wasps showed that Wolbachia endosymbionts do not affect development of the host female reproductive tract and eggs, but do enhance host-searching ability of female wasps. These results suggest the possibility that Wolbachia endosymbionts may promote their diffusion and persistence in the host A. japonica population not only at least partly by parthenogenesis but also by enhancement of oviposition frequency of the host females.

Switching between humoral and cellular immune responses in Drosophila is guided by the cytokine GBP

Insects combat infection through carefully measured cellular (for example, phagocytosis) and humoral (for example, secretion of antimicrobial peptides (AMPs)) innate immune responses. Little is known concerning how these different defense mechanisms are coordinated. Here, we use insect plasmatocytes and hemocyte-like Drosophila S2 cells to characterize mechanisms of immunity that operate in the haemocoel. We demonstrate that a Drosophila cytokine, growth-blocking peptides (GBP), acts through the phospholipase C (PLC)/Ca(2+) signalling cascade to mediate the secretion of Pvf, a ligand for platelet-derived growth factor- and vascular endothelial growth factor-receptor (Pvr) homologue. Activated Pvr recruits extracellular signal-regulated protein kinase to inhibit humoral immune responses, while stimulating cell 'spreading', an initiating event in cellular immunity. The double-stranded RNA (dsRNA)-targeted knockdown of either Pvf2 or Pvr inhibits GBP-mediated cell spreading and activates AMP expression. Conversely, Pvf2 overexpression enhances cell spreading but inhibits AMP expression. Thus, we describe mechanisms to initiate immune programs that are either humoral or cellular in nature, but not both; such immunophysiological polarization may minimize homeostatic imbalance during infection.

Immunoevasive protein (IEP)-containing surface layer covering polydnavirus particles is essential for viral infection

Polydnaviruses (PDVs) are unique symbiotic viruses associated with parasitoid wasps: PDV particles are injected into lepidopteran hosts along with the wasp eggs and express genes that interfere with aspects of host physiology such as immune defenses and development. Recent comparative genomic studies of PDVs have significantly improved our understanding of their origin as well as the genome organization. However, the structural features of functional PDV particles remain ambiguous. To clear up the structure of Cotesia kariyai PDV (CkPDV) particles, we focused on immunoevasive protein (IEP), which is a mediator of immunoevasion by the wasp from the encapsulation reaction of the host insect's hemocytes, because it has been demonstrated to be present on the surface of the virus particle. We discovered that IEP tends to polymerize and constitutes a previously unidentified thin surface layer covering CkPDV particles. This outermost surface layer looked fragile and was easily removed from CkPVD particles by mechanical stressors such as shaking, which prevented CkPDV from expressing the encoded genes in the host target tissues such as fat body or hemocytes. Furthermore, we detected IEP homologue gene expression in the wasp's venom reservoirs, implying IEP has another unknown biological function in the wasp or parasitized hosts. Taken together, the present results demonstrated that female C. kariyai wasps produce the fragile thin layer partly composed of IEP to cover the outer surfaces of CkPDV particles; otherwise, they cannot function as infectious agents in the wasp's host. The fact that IEP family proteins are expressed in both venom reservoirs and oviducts suggests an intimate relationship between both tissues in the development of the parasitism strategy of the wasp.

[Study of ruptured intracranial aneurysms with intracerebral hematomas--with special reference to operative indication]

We reviewed 40 cases of intracranial ruptured aneurysm with intracerebral hematoma (An-ICH) and compared those with 177 cases of intracranial single ruptured aneurysm causing only subarachnoid hemorrhage (An-SAH). An-ICH accounted 11.6% of the intracranial aneurysm, ruptured at the mean age of 54 years, and occurred equally in both sexes. The localization of An-ICH was 50% in the middle cerebral artery (MC), 43% in the anterior cerebral artery (AC) and 8% in the internal carotid arterial region. Forty percent of An-ICH were treated conservatively and the outcome was very misery (no useful life and 94% was poor or dead). Sixty percent of An-ICH were treated surgically (neck-clipping and removal of the hematoma) and the outcome was poor (17% useful life and 46% poor and dead). Especially in MC aneurysm, operability was 85% and post-operative useful life was 12% and post-operative poor or dead was 53%. In AC aneurysm, operability was 35% and post-operative useful life was 33% and poor or dead was 33%. These miserable results raised a question of operative indication for An-ICH. The five clinical indices (decerebration, hypertension greater than or equal to 200 mmHg, Hunt-Hess grade V, anisocoria in AC, severe shift of midline structure on X-CT) were selected, because any patients who presented with even only one of them became fatal or vegetative state regardless of conservative or surgical treatment. Assuming them as the non-operative standards, operability decreased in 35% MC, 29% AC, useful life outcome came up to 20% MC, 40% AC, and misery outcome came down to 20% MC, 20% AC.(ABSTRACT TRUNCATED AT 250 WORDS)

[Analysis of 223 cases of intracranial aneurysms--with special reference to re-rupture of the intracranial aneurysms]

Reviewing 223 cases of intracranial ruptured aneurysms including 46 cases of re-ruptured aneurysms, the following results were obtained. 1) The outcome of the re-rupture aneurysms was more miserable than that of the first rupture. Even low grade cases (Hunt and Hess 0-II) of re-rupture showed no better outcome than high grade cases (Hunt and Hess IV) of first rupture. 2) Re-rupture most often occurred on the 12th (11.6 +/- 6.7) day after the first attack of the subarachnoid hemorrhage. Re-rupture more often occurred in the vertebrobasilar system. In the internal carotid artery and its branches, aneurysms with daughter or bleb tended to rupture again. Aneurysms with daughter, regardless of these location, showed greater incidence of re-rupture than those without daughter. Also rupture often occurred in the cases of lower grade with less vasospasm and with the acute hydrocephalus. 3) It was suggested that the sequential changes of some factors of both the coagulating system and fibrinolytic system might forecast the vasospasm, infarction, re-rupture and prognosis of the patient of intracranial ruptured aneurysms. And therefore, in the cases in which re-rupture is likely, operation should be performed as early as possible, except in those showing diffuse vasospasm or clinical down hill course or in grade V.