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Background Baloxavir marboxil (baloxavir) is a single-dose, oral antiinfluenza drug with a novel mechanism of action. We compared the incidence of hospitalization in patients treated with baloxavir vs neuraminidase inhibitors. Methods In this retrospective, observational, cohort study, we used real-world patient data extracted from a Japanese health insurance claims database. The enrollment period was 1 October 2018 to 17 April 2019. On day 1, eligible patients (N = 339 007) received baloxavir, oseltamivir, zanamivir, or laninamivir. Baseline characteristics were standardized using the inverse probability of treatment weighting method. The primary end point was the incidence of hospitalization (days 2–14). Secondary end points included antibacterial use, secondary pneumonia, and additional antiinfluenza drug use. Results Compared with the baloxavir group, the incidence of hospitalization was greater in the oseltamivir group (risk ratio [RR] and 95% confidence interval [CI], 1.41 [1.00–2.00]; risk difference [RD] and 95% CI, 0.06 [.01–.12]) and zanamivir group (RR, 1.85 [1.23–2.78]; RD, 0.11 [.02–.20]). Oseltamivir-treated patients were less likely to require antibacterials than baloxavir-treated patients (RR, 0.87 [.82–.91]). However, oseltamivir-treated patients were more likely to be hospitalized with antibacterials (RR, 1.70 [1.21–2.38]) or antibacterial injection (RR, 1.67 [1.17–2.38]) than baloxavir-treated patients (post hoc analysis). Compared with baloxavir-treated patients, additional antiinfluenza drug use was greater in oseltamivir-, zanamivir-, and laninamivir-treated patients (RR, 1.51 [1.05–2.18], 2.84 [2.04–3.96], and 1.68 [1.35–2.10], respectively). Conclusions Baloxavir is an efficacious antiinfluenza treatment that may reduce hospitalization compared with oseltamivir and zanamivir. Clinical Trials Registration University hospital Medical Information Network Clinical Trials Registry (UMIN000038159). [ABSTRACT FROM AUTHOR]

Background Baloxavir marboxil (baloxavir) is expected to reduce influenza transmission by rapid reduction of viral load. The incidence of household transmission was compared between index patients (IPs) treated with baloxavir and those treated with neuraminidase inhibitors. Methods Using a Japanese claims database, the first family members with influenza diagnosis during the 2018–2019 influenza season were identified as IPs, and the diagnosis date was designated day 1. According to the anti-influenza drug dispensed to the IP, their families were classified into the oral baloxavir group and 3 controls: oral oseltamivir group (a primary control), inhaled zanamivir group, and inhaled laninamivir group. A household transmission was defined as influenza diagnosed for any non-IP family members during days 3−8. The incidence of household transmission was compared between groups using a logistic regression model adjusting backgrounds of IPs. Results The proportion of families with household transmission was 17.98% (15 226 of 84 672) in the baloxavir group and 24.16% (14 983 of 62 004) in the oseltamivir group. The covariate-adjusted odds ratio (oseltamivir/baloxavir) was 1.09 (95% confidence interval [95% CI], 1.05–1.12), which indicated significantly lower incidence in the baloxavir group. The adjusted odds ratios (controls/baloxavir) against zanamivir and laninamivir were 0.93 (95% CI,.89–.97) and 0.99 (95% CI,.96–1.02), respectively. Conclusions Baloxavir may contribute to reduction in household transmission compared with oseltamivir. In comparison between baloxavir and inhalants, a similar reduction was not shown and it might be due to unmeasured confounding by administration route differences. [ABSTRACT FROM AUTHOR]

Close associations of certain lepidopteran taxa with pyrrolizidine alkaloids (PAs), a typical class of plant secondary metabolites, have been well documented from the perspective of evolutionary ecology. Male danaine butterflies are thought to utilize PAs as precursors for the production of dihydropyrrolizines [e.g. danaidone (DO) and hydroxydanaidal (HD)] in their two distinct androconial organs, viz. alar scent organs (sex brands) and abdominal hairpencils. However, little is known about the quantitative profiles of these compounds in danaines, the mechanism for their formation in the androconial organs, or their biological functions, particularly in mating behaviour. The present study addressed these unanswered questions posed for males of the danaine butterfly, Parantica sita. Chemical analyses of androconial extracts revealed considerable seasonal/regional and individual variations of the amounts of DO (the major dihydropyrrolizine produced) and 7 R-HD (the 7 R-enantiomer of HD detected in this study) found in the two organs. These variations seemed to depend primarily on the age of the male and the phenological traits of PA-containing plants available. Males were found to acquire an adequate capability to produce DO ~1 week after eclosion. DO was shown to be produced exclusively in the sex brand and subsequently physically transferred to the hairpencil through a contact behaviour between the two organs, here termed 'perfuming behaviour'. The results of behavioural experiments with PA-fed and PA-unfed males that were allowed to compete for mates, combined with the positive electroantennographic (EAG) responses of the female, to both DO and 7 R-HD, led to the conclusion that either or both of these compounds can act as the sex pheromone. Oral administration of PAs to males indicated that DO can be biosynthesized from various PA precursors, while 7 R-HD, unlike in arctiid moths, is derived only from PAs with the 7 R-configuration. The putative biosynthetic pathways of DO and 7 R-HD, and the evolutionary provenance of the binate androconial system in the Danainae are also discussed. [ABSTRACT FROM AUTHOR]

Background: Model-based type iterative reconstruction algorithms with fast reconstruction times are now available. The clinical feasibility of their reconstruction has not been evaluated adequately.Purpose: To investigate the effects of model-based type iterative reconstruction, i.e. iterative model reconstruction (IMR), with fast reconstruction time on the qualitative and quantitative image quality at low-dose chest computed tomography (CT).Material and Methods: Thirty-one patients undergoing low-dose screening chest CT were enrolled. Images were reconstructed using filtered back projection (FBP), hybrid iterative reconstruction (HIR), and IMR algorithms. The CT attenuation and image noise for all reconstructions were calculated at the lung apex, middle, and base. Using a 4-point scale, two reviewers visually evaluated the image quality with respect to vessel sharpness, streak artifact, the mediastinum, and the overall image quality of each reconstruction method.Results: The mean estimated effective dose was 1.0 ± 0.3 mSv. There was no significant difference in the CT attenuation among the three reconstructions. The mean image noise of FBP, HIR, and IMR images was 124.3 ± 57.3, 34.8 ± 10.2, and 22.9 ± 5.8 HU, respectively. There were significant differences for all comparison combinations among the three methods (P < 0.01). The best subjective overall image quality for the lung and mediastinum was obtained with IMR (P < 0.01). The reconstruction time for IMR was within 3 min in all cases.Conclusion: At low-dose chest CT, IMR can improve the qualitative and quantitative visualization of both lung and mediastinal structures especially in the lung apex at a clinically acceptable reconstruction time. Its application may improve diagnostic performance. [ABSTRACT FROM AUTHOR]

Background: The 256-slice computed tomography (CT) scanners with wider detector coverage and faster gantry rotation speed are now available. The performance of scanners that feature a rotation speed of 270 ms at coronary CT angiography (CCTA) has not been evaluated in patients with a higher heart rate.Purpose: To evaluate the image quality of 256-slice CT with faster gantry rotation speed in patients undergoing CCTA.Material and Methods: We enrolled 886 patients; 357(40.3%) underwent study on a 64-slice CT at a rotation speed of 420 ms, the other 529 (59.7%) were examined using a 256-slice CT scanner at 270 ms. Two observers judged the image quality of 2658 imaged coronary arteries on a 4-point scale.Results: The mean image quality score was significantly higher for the 256 - than the 64-slice CT scans (3.94 ± 0.28 vs. 3.73 ± 0.61; P < 0.01). There was no significant difference in the image quality scores between 64 - and 256-slice scans in patients whose heart rate (HR) was <60 bpm. However, in patients whose HR exceeded 60 bpm these scores were significantly higher for 256-slice CT images (P < 0.01).Conclusion: CCTA performed on the 256-slice CT scanner yielded significantly better image quality in patients with an HR exceeding 60 bpm. [ABSTRACT FROM AUTHOR]

Abstract: Adult nymphalid butterflies possess sensilla trichodea (ST) that perceive taste in their walking legs. We examined whether the gustatory responses to mid-leg tarsal stimulation were different between Vanessa indica (rotting-food feeder) and Argyreus hyperbius (flower-nectar feeder). Sucrose, fructose, and glucose elicited behavioral responses (proboscis extension reflex: PER) and electrophysiological responses (spikes) from ST. Sugar responsiveness was similar in both species, where sucrose was the most stimulatory. Two fermentation products, ethanol and acetic acid, never induced PERs but elicited large-amplitude spikes at a concentration of >1% (w/v). The two species significantly differed in responsiveness to the binary mixtures of sucrose and the fermentation products. Ethanol enhanced the sugar responses of V. indica but slightly inhibited those of A. hyperbius. Although acetic acid suppressed the sugar responses of both species, V. indica was less susceptible than A. hyperbius. When concentration of the fermentation products increased, binary mixtures evoked large spikes together with small ones regarded as the sucrose responses. Unlike the proboscal sensilla in our previous study, the tarsal ST of both species unambiguously responded to fermentation products. These results demonstrate that the tarsal gustatory sense of V. indica is adaptive to the use of rotting foods. [Copyright &y& Elsevier]

A positive relationship between ownership and contest success is widespread among territorial butterflies. We tested the hypothesis that owners win simply because they have a longer experience occupying a given territory than do intruders in territorial butterflies. Using the lycaenid butterfly Chrysozephyrus smaragdinus, we staged contests between two males that had experienced different residency periods at the same contested territory, similar to owners and intruders in natural contests. We found that males that had occupied the contested territory for a longer period (a day) always defeated the shorter occupancy males (15 min). Therefore, residency period plays a key role in settling territorial contests. As residency confers advantages in a time-dependent manner, the mechanism of owner dominance could be an increase in motivation to fight as local familiarity increases. Moreover, this result predicts a population-level territorial dynamics. If residency period per se confers advantages in each contest, males arriving at a territory early in their adult season should acquire territorial dominance because they can remain there for a certain period with only a few rivals; late-appearing males do not have this advantage. As predicted, we found that males appearing at territory sites early in the season were more likely to hold their territories. This finding provides new evidence for the evolution of protandry in butterflies. [ABSTRACT FROM AUTHOR]

Abstract: Two compounds, 9,10-epoxytetrahydroedulan (ET) and viridiflorine β-lactone (VL), were identified as major components from the hairpencils of field-caught males of a danaid butterfly, Euploea mulciber. By contrast, laboratory-reared males entirely lacked VL, but possessed a significant quantity of ET. Various feeding experiments with larvae and indoor adult males strongly suggested that ET is biosynthesized de novo only after eclosion from nutrients ingested during the larval development. Since VL was suspected to be derived from pyrrolizidine alkaloids (PAs) acquired as an adult, tests for feeding response to and oral administration of four PAs (a 4:1 mixture of intermedine/lycopsamine, heliotrine, monocrotaline, and retronecine) were conducted. When the tarsi or proboscis were stimulated with PA solutions, males showed positive feeding responses (proboscis extension and sucking movements) to intermedine/lycopsamine, heliotrine, and retronecine in decreasing order of responsiveness, thereby providing evidence that male adults are endowed with taste receptor(s) specific to PAs on the legs as well as on the proboscis. Differently from gustatory responsiveness, only males fed with intermedine/lycopsamine produced a significant quantity of VL (ca. 35μg/male), whereas those that ingested heliotrine or monocrotaline hydrochloride produced traces of VL (<0.18μg/male). Uptake of retronecine did not lead to VL formation at all. In behavioral bioassays to test the attractivity of PAs to males, all individuals tested were attracted exclusively to intermedine/lycopsamine. This shows that certain PA(s) per se serve as attractant(s) for males in locating PA sources, and further suggests that in the field, males will seek particular PA(s) that are indispensable as precursors for the efficient biosynthesis of VL. [Copyright &y& Elsevier]

Most flower visitors innately prefer a particular color and scent, and use them as cues for flower recognition and selection. However, in most cases, since color and scent serve as a combined signal, not only does the preference for an individual cue, but also the preference hierarchy among different cues, influence their flower visitation. In the present study, we attempted to reveal (1) the chromatic and (2) the olfactory cues that stimulate flower visiting, and (3) the preference hierarchy between these cues, using the naïve adult butterflyVanessa indica. When we offered 12 different-colored (six chromatic and six achromatic) paper flower models,V. indicashowed a color preference for yellow and blue. When we examined the proboscis extension reflex (PER) ofV. indicatowards 16 individual compounds identified in the floral scents from two nectar plants belonging to the family Compositae,Taraxacum officinaleandCirsium japonicum, six compounds were found to have relatively high PER-eliciting activities, including benzaldehyde, acetophenone, and (E+Z)-nerolidol. When we combined color and scent cues in two-choice bioassays, where butterflies were offered flower models that were purple (a relatively unattractive color), the models scented with these active compounds were significantly more attractive than the odorless controls. In addition, synthetic blends mimicking the floral scents ofT. officinaleandC. japonicum(at doses equivalent to that of ten flowers) enhanced the number of visits to the scented models. However, the effect of odorizing was not conspicuous in parallel bioassays when yellow flower models were used, and the butterflies also significantly preferred odorless yellow models to scented purple models. These results demonstrate thatV. indicadepends primarily on color and secondarily on scent during flower visitation. [ABSTRACT FROM AUTHOR]

Exuded tree sap and rotting fruits are important feeding sources for adults of many butterfly species. However, the chemical composition of such rotting foods and the effects of these constituents on butterfly feeding behaviour have rarely been investigated. Chemical analyses revealed that these food sources contain several major components, including fructose, glucose, ethanol and acetic acid. Moreover, 15 amino acids were identified from the exuded tree sap. The gustatory responsiveness to these components was examined in the proboscis of nymphalid adults of three species (Nymphalis xanthomelas, Kaniska canace and Vanessa indica). The first two species primarily feed on sap and rotting fruits, while V. indica frequently visits flowers. Fructose elicited larger feeding responses from these saprophagous butterflies than glucose, which had a feeding-stimulatory effect only on N. xanthomelas at a concentration equivalent to that of the food. Ethanol, acetic acid and the five major amino acids identified in tree sap did not elicit feeding responses by themselves. However, ethanol and/or acetic acid, when mixed with these sugars at equivalent concentrations, evoked feeding and enhanced probing responses in K. canace and V. indica. These results suggest that ethanol and acetic acid, together with sugars at low concentrations, synergistically stimulate butterfly feeding behaviour. [Copyright &y& Elsevier]

Summary Oviposition response of Ideopsis similis (L.) (Lepidoptera: Danaidae) was examined for 12 phenanthroindolizidine alkaloids present in its host plant, Tylophora tanakae (Maxim.) (Asclepiadaceae). At least five alkaloids, i.e. (+)-isotylocrebrine (3,4,6,7-tetramethoxyphenanthroindolizidine; l), (+)-3-demethyliso- tylocrebrine (3), (+)-isotylocrebrine N-oxide (5), (+)-6-demethyltylocrebrine (8) and (–)-7-demethyltylophorine (10), were found to individually stimulate oviposition by females. Of these, compounds 1, 3 and 10 were regarded as key components most responsible for host recognition or preference. However, female egg-laying was much higher in response to a mixture of the five alkaloids. In two-choice bioassays, more eggs were deposited on samples comprising the five alkaloids than on samples consisting of a single alkaloid. This suggests strongly that host selection by the butterfly is mediated by the synergistic action of several phenanthroindolizidine alkaloids present in the host plant. [ABSTRACT FROM AUTHOR]

AbstractThe active compounds of oak-sap odour in attracting adults of two butterflies, Kaniska canace (L.) and Vanessa indica (Herbst) (Lepidoptera: Nymphalidae), were identified by chemical analyses, electroantennogram (EAG) and two behavioural assays: proboscis extension reflex (PER) and attraction to artificial tree models. Fourteen compounds were identified from two sap samples collected in 1997 and 1998, of which the major volatiles were ethanol and acetic acid (≈ 900 p.p.m. and 500 p.p.m. in sap, respectively). However, the chemical composition of the minor volatiles varied considerably between the two samples. Among 13 chemicals tested, V. indica showed strong PER to five aliphatic acids (acetic, propionic, butyric, isobutyric and isovaleric), 2-methylpropan-1-ol and 3-hydroxybutan-2-one, whereas the PER-active compounds for K. canace were these seven compounds and also ethanol, 3-methylbutan-1-ol and 1-hydroxypropan-2-one. In two-choice behavioural bioassays, the model scented with a sap-odour mimic, which was an aqueous mixture of the PER-active compounds, was more attractive to the two butterflies than an unscented control. These results demonstrated that the sap odour stimulates foraging behaviour of the butterfly. Although EAG responses of both butterflies to 3-methylbutan-1-ol and that of V. indica to 2-methylpropan-1-ol were positively dose-dependent, responses to other compounds were not strong and not dose-dependent at 1–100 μg doses. These EAG responsiveness suggests that the olfactory receptors for these compounds might be few in the antenna and that the butterflies have enough olfactory sensitivity to the dose of 1 μg. [ABSTRACT FROM AUTHOR]