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Entoria okinawaensis Shiraki, 1935 (Phasmatodea: Phasmatidae) is a stick insect originally distributed among the subtropical islands of Japan. This species, after introduction into the southernmost regions of Kyushu Island, became established there. After insects were collected for this study from Ibusuki city, Kagoshima prefecture, Japan, their eggs were used for experimentation. Embryonic development was fundamentally temperature dependent. At 25 °C, many eggs hatched approximately 2 months after oviposition. However, hatching was observed continuously until the end of the 240-day experiment. Findings from egg dissection suggest that a small number of eggs arrest development at the early embryonic stages. Fluorescence observation of DAPI-stained eggs reveals that eggs show arrested development at the very attenuated blastoderm period. This study proves the existence of embryonic diapause in E. okinawaensis, although the incidence of diapause eggs is small. If future changes in the incidence and duration of diapause as adaptations to local climate occur, then the domestic-introduced subtropical stick insect might expand its distribution range farther north. [ABSTRACT FROM AUTHOR]

Shiga toxin (Stx) is the key virulence factor of Stx-producing Escherichia coli (STEC). All known Stxs (Stx1 and Stx2) are encoded by bacteriophages (Stx phages). Although the genetic diversity of Stx phages has frequently been described, systematic analyses of Stx phages in a single STEC lineage are limited. In this study, focusing on the O26:H11 STEC sequence type 21 (ST21) lineage, where the stx1a gene is highly conserved, we analysed the Stx1a phages in 39 strains representative of the entire ST21 lineage and found a high level of variation in Stx1a phage genomes caused by various mechanisms, including replacement by a different Stx1a phage at the same or different locus. The evolutionary timescale of events changing Stx1a phages in ST21 was also determined. Furthermore, by using an Stx1 quantification system developed in this study, we found notable variations in the efficiency of Stx1 production upon prophage induction, which sharply contrasted with the conserved iron regulated Stx1 production. These variations were associated with the Stx1a phage alteration in some cases but not in other cases; thus, Stx1 production in this STEC lineage was determined by differences not only in Stx1 phages but also in host-encoded factors. [ABSTRACT FROM AUTHOR]

Background: Irritable bowel syndrome (IBS) is a disorder of gut-brain interaction, including dysregulation of the hypothalamic-pituitary-adrenal axis with salivary cortisol changes. However, the role of gastrointestinal microbiota during IBS symptom exacerbation remains unclear. We tested the hypothesis that the microbial species, gene transcripts, and chemical composition of fecal and oral samples are altered during the exacerbation of IBS symptoms.Methods: Fecal, salivary, and dental plaque samples were collected at baseline from 43 men with IBS with diarrhea (IBS-D) and 40 healthy control (HC) men. Samples in the IBS-D patients were also collected during symptom exacerbation. The composition of the fecal microbiota was determined by analyzing the 16S rRNA gene, RNA-based metatranscriptome, and metabolites in samples from HC and IBS patients with and without symptom exacerbation. Oral samples were also analyzed using omics approaches.Results: The fecal microbiota during IBS symptom exacerbation exhibited significant differences in the phylogenic pattern and short-chain fatty acid compared with fecal samples during defecation when symptoms were not exacerbated. Although there were no significant differences in the phylogenic pattern of fecal microbiota abundance between HCs and IBS-D patients, significant differences were detected in the expression patterns of bacterial transcriptomes related to butyrate production and neuroendocrine hormones, including tryptophan-serotonin-melatonin synthesis and glutamine/GABA. The composition of plaque microbiota was different between HC and IBS-D patients during normal defecation.Conclusions: Our findings suggest that colonic host-microbial interactions are altered in IBS-D patients during exacerbation of symptoms. There were no overlaps between feces and oral microbiomes. [ABSTRACT FROM AUTHOR]

The Japanese pavement ant Tetramorium tsushimae Emery (Formicidae) is a species of seed-collecting ant found in Japan. However, its role in seed dispersal has not yet been satisfactorily documented. We investigated the seed-carrying behaviour of T. tsushimae both in the laboratory and in the field. In the laboratory, seeds of three common weeds [evening primrose Oenothera biennis (Onagraceae), purslane Portulaca oleracea (Portulacaceae), and dropseed Sporobolus fertilis (Poaceae)] were examined. More than 65% of each kind of seed was carried by the ants, but some were later discarded outside the nest. Among the three, S. fertilis seeds were collected most frequently. The germination rate of the seeds was higher than 80% for both discarded and stored O. biennis and S. fertilis seeds but lower than half for discarded P. oleracea seeds. In the field, the relationship between the ants and the growing locations of O. biennis or P. oleracea was investigated. The distribution of O. biennis plants considerably overlapped with the distribution of T. tsushimae nest holes at all survey sites. The distribution of P. oleracea also overlapped with that of ant nest holes at some sites. In areas where O. biennis and P. oleracea were absent, a high proportion (> 65%) of artificially placed seeds were carried by T. tsushimae. A few months later, O. biennis seedlings were observed near many ant nest holes. The mean distance between the seedlings and seed-set point was 7.2 m. Although P. oleracea seeds were observed near nest holes, their seedlings were not detected. The present results suggest that O. biennis plants benefit from seed dispersal by T. tsushimae and that the distribution of P. oleracea plants might also be influenced by ant foraging behaviour. [ABSTRACT FROM AUTHOR]

References 1 Tanaka Y, Yamashita R, Kawashima J. Omics profiles of fecal and oral microbiota change in irritable bowel syndrome patients with diarrhea and symptom exacerbation. There are reports that the low fermentable oligosaccharides, disaccharides, monosaccharides, and polyols (FODMAP) diet can modify the gut microbiota of IBS patients who have pathogenic gut microbiota closer to that of healthy individuals [[5]]. [Extracted from the article]

For Lasius japonicus Santschi (Hymenoptera: Formicidae), a common ant species in Japan, diapause induction is temperature dependent. To elucidate the geographic variation of its temperature dependence, new L. japonicus queens were collected immediately after nuptial flight from four sites at different latitudes: Kitami (44.1°N), Hakodate (41.8°N), Shizuku-ishi (39.7°N), and Okayama (34.7°N). The collected queens were reared for 100 days at four constant-temperature conditions (25 °C, 20 °C, 17.5 °C, and 15 °C) under a 12L:12D photoperiod. The queens began founding colonies immediately in all conditions. For all temperature conditions, daily change patterns of the average numbers of eggs, larvae, and pupae were similar among the Hakodate, Shizuku-ishi, and Okayama populations, but the development patterns of the Kitami colonies differed from those of the other three sites. Low temperatures strongly suppressed colony development of the Kitami population; development was weak even at moderate temperatures. For new queens of L. japonicus, solitary overwintering without rearing larvae is regarded as serving an important role in successful colony foundation under cool climate conditions. Results reported herein suggest that local temperatures exert important selective pressure on the timing of diapause induction and on colony development in northern populations. [ABSTRACT FROM AUTHOR]

Although day length plays a critical role in the seasonal development of many temperate insects, this study showed that this variable is less important than temperature for seasonal regulation of an ant's life cycle. Here, we examined the effects of temperature on queen oviposition and seasonal colony development of Lasius japonicus Santschi. Queens were collected soon after their nuptial flight and were reared under constant laboratory conditions; colony development was analyzed. The percentage of larvae- and pupae-emerged colonies was reduced in low rearing temperatures, indicating that temperature is the primary environmental factor for the regulation of seasonal development. Larval diapause was induced at higher temperatures than the reproductive diapause of queens. Larvae need to enter diapause before winter; nevertheless, eggs that were still unhatched in late autumn would not necessarily be wasted because they could be eaten by queens. Cyclic fluctuation in the egg number was observed. At 25 °C, the second increase in egg number was synchronized with pupation, suggesting a social effect on queen oviposition. In contrast, at 20 and 17.5 °C, the clear second peak of oviposition was found in colonies wherein larvae did not emerge, suggesting that endogenous rhythmicity is involved in the regulation of queen oviposition. [ABSTRACT FROM AUTHOR]

Geographical differences causing variations in the egg period and the effects of environmental factors on diapause development were examined in Sympetum frequens (Selys), a univoltine species with an obligatory egg diapause for overwintering. Eggs were obtained from females collected from 11 localities in Japan and incubated under six different combinations of photoperiod and temperature. No clear geographical trends were found in the average egg period under any experimental treatment. Average hatch period (i.e., period from the date when 10 % of the eggs were hatched to the date when 90 % of the eggs were hatched) did not display any geographical trend at 25 and 20 °C. However, at 15 °C, a significant negative correlation was observed between the hatch period and the latitude of the collection site. Similarly, a significant correlation was also detected between the coefficient of variation in the egg period and the average annual temperature near the collection site, but only at 15 °C. Because each egg batch was divided into six groups which were then incubated under different experimental conditions, it was possible to discern that the rate of diapause development at 15 °C varies among eggs from southern populations. The large variations in the egg period in the southern populations at 15 °C were considered to be a risk-spreading strategy: a certain proportion of the eggs were able to maintain diapause until winter, even if the adults laid the eggs early in the season. These differences in the rate of diapause development within a population may be an adaptation to the unpredictable length of the summer-autumn period. [ABSTRACT FROM AUTHOR]

We propose a method for observing the propagation-angle displacement of a collimated beam with respect to the travel direction of a moving part by use of a dual-focus Fresnel lens. The fabricated binary-type dual focus Fresnel lens consisting of two portions having a different focal length from each other. 0.5 mrad angular accuracy within a travel range of 16 mm was experimentally confirmed and then it was successfully applied to split-type optical head manufacturing. [ABSTRACT FROM AUTHOR]

The C-deoxy- d-glucose technique was used to examine glucose utilization, as a measure of neuronal activity, in 100 cerebral nuclei by means of radiodensitometry of autoradiographs of serial brain sections. Three groups of rats were studied, namely young spontaneously hypertensive rats (SHR), adult SHR and normal Wistar-Kyoto rats whose blood pressure was acutely increased by injection of angiotensin II. In all three groups as compared to corresponding normotensive controls, glucose utilization was consistently increased in the caudal part of the nucleus (n.) tractus solitarii, medullary related nuclei (n. commissuralis, area postrema and n. dorsalis nervi vagi), n. centromedianus, n. habenulae lateralis, n. supraopticus, n. paraventricularis, n. suprachiasmaticus, n. periventricularis, n. amygdaloideus centralis, and area amygdaloidea anterior. The increase in glucose utilization in these areas is probably due to facilitation of baroreceptor afferent impulses. In young SHR at 4 weeks of age (but not in other groups), increased glucose utilization was found in limbic areas such as the n. interpeduncularis, n. dorso-and ventro-medialis thalami, area anterior and n. dorsomedialis hypothalami, fasciculus medialis telencephali (caudal), n. amygdaloideus lateralis and intercalatus, stria terminalis nuclei, n. dorsalis and intermedius septi, and n. caudatus. In adult SHR at 20 weeks of age (but not in other groups), there was an increase in glucose utilization in the n. intercalatus, n. originis nervi hypoglossi, n. olivaris superior, n. parabrachialis dorsalis and ventralis, substantia grisea centralis, n. paramedianus, reticular formation areas such as n. centralis superior, n. reticulotegmentalis pontis, n. reticularis lateralis and n. tegmentalis pedunculopontinus and substantia reticularis mesencephali, n. corporis mamillaris medialis, n. arcuatus, infundibulum, fasciculus longitudinalis dorsalis and hippocampus ventralis. In SHR at both ages, there was an increase in glucose utilization in most of the sensory trigeminal nuclei, which might indicate enhanced perception of sensory inputs, probably leading to peripheral vasoconstriction. Also in SHR at both ages, increased glucose utilization was found in the substantia nigra pars compacta, n. tegmenti dorsalis and ventralis, fasciculus medialis telencephali (rostral), n. amygdaloideus medialis, n. tractus olfactorii lateralis and n. lateralis septi. In conclusion, baroreceptor-independent neuronal activation in the limbic area in young SHR and in the reticular formation, periventricular fibers and arcuate-infundibular system in adult SHR, in addition to the sensory trigeminal nuclei and tegmental tract at both ages, might be involved in the development and maintenance of hypertension in SHR. [ABSTRACT FROM AUTHOR]

In young and adult spontaneously hypertensive rats (SHR), dopamine β-hydroxylase (DBH) and phenylethanolamine N-methyltransferase (PNMT) activities in discrete areas of the brainstem and spinal cord were measured as indices of noradrenergic and adrenergic neuronal activities. In young SHR, the DBH activities were elevated in the locus coeruleus (LC), A2 cell area and thoracic intermediolateral cell area (IML). The elevation disappeared at adult SHR. In young SHR, no significant change of PNMT activity was observed in the A1, A2, nucleus tractus solitarii (NTS), LC and IML areas, while, in adult SHR, the PNMT activity in the A1 cell area and DBH activity in the NTS were elevated. Lowering of blood pressure by hydralazine decreased the PNMT activity elevated in the A1 cell area and elevated it in the NTS. Plasma levels of norepinephrine and epinephrine, as measured in blood samples collected via aortic cannula at resting state, were much lower than many reported values in blood collected from the decapitated trunk. In young SHR, a significant elevation of plasma norepinephrine and DBH levels was confirmed as signs of peripheral sympathetic nervous activation. The elevation disappeared at adult SHR. Plasma epinephrine levels raised under restraint stress were much higher in SHR at all ages than in normotensive controls. In young SHR, the selective activation of noradrenergic neurons of the IML, A2 and LC areas, accompanied by activation of the peripheral sympathetic nervous system, initiates the hypertension. In adult SHR, the activation of adrenergic neurons in the A1 cell area including the nucleus reticularis lateralis may not be involved in the maintenance of hypertension but may be the results of hypertension. [ABSTRACT FROM AUTHOR]

In young, spontaneously hypertensive rats (SHR), a preganglionic, nerve-dependent, elevation of choline acetyltransferase (ChAc) and tyrosine hydroxylase (TH) activities was found in celiac ganglia as compared with those in young, normotensive Kyoto Wistar rats, that was not present in superior cervical ganglia, stellate ganglia and adrenal glands. The rise in both enzyme activities in the celiac ganglion disappeared in adult SHR. An elevation of plasma norepinephrine and dopamine β-hydroxylase levels found in prehypertensive SHR, a probable indication of peripheral sympathetic activation, disappeared after the bilateral removal of the celiac ganglion. However, ganglionectomy did not change the subsequent development of hypertension. These results indicate that the faster maturation of the celiac ganglion and the end organs it innervates in young SHR are causally related to the activation of the peripheral sympathetic nervous system. The peripheral sympathetic activation in young SHR is regarded as a warning sign but this does not trigger the development of hypertension. [ABSTRACT FROM AUTHOR]

The oral administration of 100 mg/kg/day of DPH or P-6127 to dogs and cats for more than 1 year resulted in preferential accumulations of the drugs in the superior and inferior colliculus, amygdala, and hippocampus compared to 16 other cerebral areas examined without any manifestation of neurotoxicity. The relative brain to blood levels of DPH in the animals were higher than those of epileptic patients on a maintenance dose. Both drugs were found concentrated in the pituitary and adrenal; P-6127 less so than DPH. This may be the cause of the infrequent gingival hyperplasia or hirsutism. DPH was metabolized to the pharmacologically inactive HPPH and a trace of inactive DPHA was found in the chronically treated animals. The ethoxycarbonyl group of P-6127 was split off to form DPH. The brain/blood and brain/cerebrospinal fluid concentration ratios were higher for P-6127 than for DPH. This may explain the greater anticonvulsant activity of P-6127 in the animals. [ABSTRACT FROM AUTHOR]

The article describes the case of pyogenic splenic abscess in a seventh-month-old boy with serological evidence of cat scratch disease. Immaturity of the patient's immune system might have contributed to the suppuration of the splenic granuloma. New pyogenic abscesses quickly developed one after another, forcing physicians to consider splenectomy.