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In novel plant–insect relationships, oviposition preference and nymphal performance determine host range evolution. Corythucha marmorata, native to North America and specialist on asteraceous plants, has been reported to exploit sweet potato (Convolvulaceae) in Japan. Here we examined the capability of females to oviposit and of nymphs to grow on both a conventional host (goldenrod, Solidago altissima) and novel hosts (four sweet potato cultivars), of which the test insects had virtually no experience of contact at the population level. We then tested whether female preference and offspring performance were correlated. Nymphal survival and development time were always significantly greater on goldenrod, followed by sweet potato cultivars Caroline Lea, Benisengan, Narutokintoki, and Beniazuma in that order. Female oviposition preferences showed a similar order. On higher-ranked plants, the females accepted the plant faster and had higher fecundity. When goldenrod was included in the analysis, nymphal development time and survival rate were significantly related to preoviposition period. When goldenrod was excluded, nymphal survival rate was still significantly related to preoviposition period. These results support the theory that females lay their eggs on the most suitable host to maximize offspring fitness, even though C. marmorata had no experience with sweet potato cultivars. As C. marmorata is a hemimetabolous insect, in which adults and nymphs have a similar feeding habit and exploit the same habitat, this relationship seems plausible.

Bactrocera carambolae and B. dorsalis (Diptera: Tephritidae) are extremely destructive pests of fruits and vegetables in the Asia-Pacific region. Earlier reports have described that B. carambolae and B. dorsalis, respectively, use mainly star fruit and mango, suggesting a certain level of host partitioning which can be ascribed neither to differences in larval food qualities nor host-specific parasitoid mortality. This study specifically examined reproductive interference (antagonistic sexual interaction) between B. carambolae and B. dorsalis as a potential factor strongly affecting their host partitioning. We observed mating behaviors, especially interspecific courtships and mating, by cohabiting the conspecific and heterospecific pairs together. Consequently, we quantified their effects on the reproductive success of females. Males of both species frequently courted their own females, but they also courted females of other species. Courtship refusal by females was not selective in males of either species. This incomplete discrimination of both sexes led to frequent occurrences of interspecific sexual interactions in both species, but only B. carambolae females showed reduced reproductive success. These results suggest that B. dorsalis, superior in reproductive interference, can occupy high-quality mango, whereas B. carambolae, inferior in reproductive interference, must use low-quality star fruit.

In order to elucidate the dominant–subordinate relationship between the foundress and workers, five colonies of the paper wasp Polistes japonicus were observed in a netted and covered cage located outdoors. The number of workers in each colony ranged from four to eight. Workers were divided into first and second broods. Abdominal wagging and ovipositing were performed almost exclusively by the foundress throughout colony development. However, an analysis of aggressive encounters indicated that although the foundress hardly received dominance behaviors (aggression) from workers, it lacked either partially or completely the following characteristics of the queen that are usually seen in paper-wasp colonies with independent-founding queens (except in one colony that produced no second brood): the queen being socially dominant over any worker (The queen had more wins than losses in one-on-one dominance contests with any worker), exhibiting the highest frequency of dominance behaviors, and directing dominance behaviors primarily toward the socially most-dominant worker. In particular, during the mixed-brood period (when all first- and second-brood workers were present on the nest) the foundress hardly exhibited dominance behaviors toward socially dominant workers (mainly second brood) but frequently directed dominance behaviors toward socially subordinate workers (mainly first brood). The foundress disappeared in two colonies before the reproductives emerged; in these colonies the socially most-dominant worker inherited the colony and laid many eggs. The frequency of abdominal wagging by these two foundresses decreased during colony development, while it did not in the other colonies. This suggests that abdominal wagging provides information about the vigor of the performer. The superseder was socially dominant over all other workers, but spent little time wagging its abdomen and allowed some workers to lay eggs.

Dominance hierarchy in the primitively eusocial wasp Polistes japonicus was analysed in four colonies for two periods: (1) the first-brood period, when only early emerging workers are present on the nest, and (2) the mixed-brood period, when the first and second (last) broods are present on the nest. The rank in the dominance hierarchy was determined based on a sociogram showing a dominance–subordinance relationship for all pairs of workers. During the first-brood period, older workers were likely to be more dominant (older dominance hierarchy), while the rank of workers was reversed during the mixed-brood period, with younger workers being likely to be more dominant (younger dominance hierarchy). However, the oldest and youngest workers were not always the top-ranked workers in the dominance hierarchy during the first- and mixed-brood periods, respectively, and during the mixed-brood period no younger dominance hierarchy was evident when the first or second brood was analysed separately. Higher ranked workers displayed dominance behaviour more frequently, and the lowest ranked worker hardly displayed dominance behaviour. Most workers displayed dominance behaviours primarily towards the worker ranked immediately below in the dominance hierarchy during the mixed-brood period but not during the first-brood period. The bodies of younger workers were larger for the mixed brood, but not for the first brood in some colonies or the second brood in all colonies. The association between body size and rank in the dominance hierarchy was negative during the first-brood period and positive during the mixed-brood period, with a nearly significant trend also seen even when the analysis was limited to the second brood. To explain the above temporal change from an older dominance hierarchy to a younger dominance hierarchy, we propose the hypothesis that the probability of a worker inheriting the colony increases rapidly with colony development, and consequently younger larger workers attempt to move up the dominance hierarchy in order to produce their own offspring by becoming the superseder late in colony development, rather than working harmoniously so as to boost the overall production of reproductive progeny for a colony, which is the strategy adopted early in colony development.

Carpophilus marginellus is a candidate pollinator of the subtropical orchard trees cherimoya and atemoya. We investigated the developmental period and adult size of this species at constant temperatures of 18, 20, 25, and 30°C as basic information for mass rearing and release in greenhouses as a pollinator. The photoperiod was 16-h light/8-h dark at all temperatures. The developmental period was shorter and the adult size was smaller at higher temperatures. Mortality was lowest at 25°C and highest at 30°C. The thermal threshold (developmental zero) ranged from 11.9 (female larvae) to 15.6°C (female pupae) among developmental stages and sexes. The thermal constant (total effective temperature) of the period from egg to adult emergence was ca. 292 degree-days.

The life cycle of Hypsopygia postflava, a moth parasitic on nests of the paper wasp Polistes jokahamae, was studied in Mie, Saitama and Tokyo in 2002 and 2003. The emergence of some overwintered-generation moths was extremely delayed, and some second-generation larvae overwintered without pupation; therefore, it is considered that this nest-parasitic moth typically completes three generations per year, with some completing only one or two generations. The proportion of male adults per nest was 56.4% on average, and ranged from 30.8% to 75.0%, but did not differ significantly with the nests. The head widths of overwintering moth larvae varied greatly between the nests and also within some of the nests. Larvae with a head width of

We investigated the mating, oviposition, and prey use by larvae of Hypsopygia postflava, a moth that is parasitic on nests of the paper wasp, Polistes jokahamae, in the laboratory under natural temperature, humidity, and day-length conditions, and in field cages. Mating occurred mainly from 2300 to 0600 hours, and copulation lasted a mean of 80.4 min. When adult wasps were absent from the nest, female adults of the moth laid eggs singly or in clumps of a few eggs, mainly on the walls of cells containing cocoons with live pupae or pupal exuviae. When adult wasps were present on the nest, wasp attacks prevented female moths from approaching the nest, and so they laid eggs singly or in clumps of several tens around the base of the nest pedicel. Female moths laid a mean of 133.9 eggs during their mean lifetime of 10.7 days. When first-instar larvae were released 10 cm from the base of the nest pedicel, 55% of them arrived in the nest with adult wasps. Moth larvae fed on wasp pupae first, and then on wasp larvae.

The cherimoya is an orchard tree that is not pollinated by bees. To identify likely pollinators, and to describe community diversity, we surveyed flower visitors at four sites in Wakayama and Mie prefectures, and found 569 individuals from 31 species of arthropods. Two of these species were arachnid and the others were insects. The most abundant species in terms of per capita density was Mimemodes monstrosus (Rhizophagidae), followed by species in the genus Phloeonomus (Staphylinidae) and Cortinicara gibbosa (Lathridiidae). Two nitidulid species, Carpophilus marginellus and Haptoncus ocularis, were also common. Among them, M. monstrosus, C. marginellus and H. ocularis, especially the former two, were regarded as good candidates for pollinators. All of the dominant species were beetles. C. gibbosa was most abundant early in the flowering season, whereas Phloeonomus sp. showed two peaks, in late May and late July. Species richness, S′ (45), ranged from 5.4 to 9.0, while heterogeneity measures, 1-D and exp H′, ranged from 0.59 to 0.78 and from 3.5 to 5.9, respectively. The index of similarity, Cλ, varied from 0.04 to 0.76, whereas the rank correlation coefficient, τ, between each site varied from −0.32 to 0.23. The contents and diversities of flower visitor communities appeared to be affected by the surrounding environment and management strategy of the orchards.

Haptoncus ocularis is a candidate pollinator of the subtropical orchard tree cherimoya (Annona cherimola). To collect basic information for the use of this species as a pollinator by mass rearing and releasing in greenhouses, the developmental period and attained adult size at constant temperatures of 15, 20, 25 and 30°C were investigated. The photoperiod was 16-h light/8-h dark at all temperatures. The developmental period was shorter at higher temperatures, except at 30°C, which lengthened pupation. Mortality from last instar larva to adult eclosion was higher at 15 and 30°C than at 20 and 25°C. The thermal threshold (developmental zero) ranged from 8.2 to 12.2°C for different developmental stages and sexes. The thermal constant (total effective temperature) of the period from egg to the next oviposition was ca. 284 degree-days. Both head width and right forewing length of the adults raised were largest at 20°C and second largest at 25°C. The maximum number of generations in a year was estimated to be nine in Wakayama, Japan.

症例は79歳の男性. 26年前に空腸腸間膜動脈瘤破裂の開腹歴があり, 高血圧症と脳梗塞で脳神経外科通院中であった. 主訴は腹痛と嘔吐で腸閉塞症の診断で当院へ入院した. 入院時, 腹部膨満と臍周囲に圧痛を認めたが腹部腫瘤は触知せず腹膜刺激症状を認めなかった. 腹部単純X線検査, 腹部エコー検査, 腹部CT小腸閉塞像を呈していた. 絞扼性イレウスの診断で緊急開腹手術を施行した. 開腹するとTreitz靱帯から約2mの回腸30cmに虚血性変化を認め, 対応する腸間膜が扇状に浮腫, 出血を呈していた. 病理組織学的には虚血性小腸炎像と腸間膜筋性動脈の壊死性動脈炎が認められた. 厚生省特定疾患の診断基準に基づき, 古典的結節性多発動脈炎と最終診断した. 術後経過は良好であった. 急性腹症で発症する結節性多発動脈炎は極めてまれであり, 自験例を含めた本邦小腸病変開腹50症例の集計検討を加えて報告する.

症例は95歳の女性. 開腹手術の既往なし. 主訴は腹痛, 嘔吐でイレウスと診断され外科転科となった. 小腸造影で小腸に滑らかな狭窄を認めた. その後, その肛門側に両端が狭窄した絞扼小腸ループ像が造影され2つの狭窄部は同位置で重なり合い, それより肛門側は造影されなかった. CT検査では腹水, 絞扼小腸像, 腸間膜の収束像を認めたが, 腫瘍など明らかなイレウスの原因を認めなかった. 以上より腸間膜や大網の裂孔による内ヘルニアと診断し, 開腹手術を施行した. Treitz靭帯より約130cmの部位から約80cmの空腸が直径約4cmの大網裂孔に嵌頓しておりこれを整復した. 術後経過は良好であった. 本症例では術前診断に小腸造影とCT検査が有用であった. 開腹歴のないイレウスの原因として内ヘルニアを念頭に置く必要があり早期診断が重要であると考えられた. なお, 本症例は本邦におけるこれまでの大網裂孔ヘルニア手術報告例の中で最高齢であった.

症例は79歳の男性で発熱, 嘔吐, 上腹部痛を主訴に当院入院となった. 臍右側に腫瘤を触知した.腹部単純X線検査, 腹部超音波検査, 腹部CT検査, 大腸内視鏡検査, 注腸造影検査にて上行結腸横行結腸型腸重積に加えて盲腸癌が嵌頓して発症したイレウスと診断され, 緊急手術を施行した. 開腹すると上行結腸が先進部となり横行結腸右側まで入り込んだ結腸結腸型の腸重積に加えて盲腸癌を先進部として回盲部, 腸間膜がさらに嵌頓した盲腸結腸型の腸重積が確認された. なお移動盲腸も認めた. 重積状態のまま結腸右半切除術, D2リンパ節郭清術を施行したが盲腸癌は5.5×5.0cmの2型で, 組織学的には高分化腺癌, stage IIであった. 上行結腸には先進部の原因となるような器質的病変は認められず, この部位の重積の発症原因は特発性と考えられた. 自験例を含む最近10年間の盲腸癌による成人腸重積症の本邦報告例27例を集計し文献的考察を加えた.

A 54-year-old woman was seen at the hospital because of a left axillary tumor. With an excision biopsy, lymph node metastasis of adenocarcinoma was diagnosed. First, metastasis from the mammary gland was suspected, but no abnormallities were found clinically in the bilateral breasts. Based on facts that immunological staining of the axillary metastatic lesion was positive for lactalbumin and no other origins were detected, occult breast cancer was most probable. A left pectoral muscle-preserving mastectomy (lt-Bt+Ax+Ic) was performed. The rescted mammary gland was histologically and minutely explored, but no malignant lesions were demonstrated. Thereafter when about 2 years has past, metastatic foci appeared in the left internal thoracic lymph node. As a result of radiation therapy and chemotherapy, the patient has been doing well as of 3 years after the operation. It is thought that immunological staining of the lymph node can offer efficient information in the diagnosis of occult breast cancer.

The egg parasitoid wasp, Anagrus takeyanus Gordh & Dunbar (Hymenoptera: Mymaridae), is one of the few natural enemies of the andromeda lace bug, Stephanitis takeyai Drake & Maa (Heteroptera: Tingidae). Studying this wasp in two habitats, I found that at Kyoto, where the bug alternates its host plants seasonally, most wasp individuals in the overwintering eggs of the bug entered summer diapause immediately after winter diapause. However, at Nara, where the bug does not alternate its host plant, the wasp proved to have no summer diapause. Changes in the parasitization rate between generations differed at the two study sites. In Kyoto, the overwintered generation suffered the highest parasitism among the three generations of the year. In contrast, the first and second generations suffered higher parasitization rates in Nara. This difference in level of parasitization between the two study sites corresponded to the different diapause regime of the wasp and the seasonal population trends of the lace bug. Laboratory experiments showed that short photoperiod in combination with low temperature could terminate the long diapause at the time the non-aestivating individuals terminate winter diapause. As a life cycle without host plant alternation is likely to be an ancestral character of the bug, the aestivation of the wasp is thought to have been appended to overwintering as an adaptation to the evolution of seasonal host plant alternation in the lace bug.

慢性膵炎に伴う膵仮性嚢胞が総胆管に穿破した症例を経験した. 症例は60歳の男性, 平成8年12月慢性膵炎の急性増悪, 膵嚢胞の診断にて当院入院となった. 腹部CT, 超音波検査では膵頭部に嚢胞を認め, 内部は均一で嚢胞壁は平滑であった. ERCPで主膵管と嚢胞に交通を認め, さらに,嚢胞は総胆管に穿破していることを確認した. 臨床経過, 画像診断などより慢性膵炎に伴う膵仮性嚢胞と診断したが, 総胆管に穿破していることより悪性の膵嚢胞性疾患も完全に否定できず, D2郭清を伴う全胃幽門輪温存膵頭十二指腸切除を施行した. 術後病理組織診にて慢性膵炎, 膵仮性嚢胞の総胆管穿破との最終診断を得た. 膵嚢胞性疾患の診断と治療にあたっては慢性膵炎に伴う多彩な合併症を念頭に置くことが重要であると考えられた.

I studied the seasonal occurrence of the andromeda lace bug,Stephanitis takeyai, on its two main host-plant species. In a secondary forest in Kyoto, this bug altered its hosts seasonally, i.e., from an evergreen shrub,Pieris japonica, in winter to a deciduous shrub,Lyonia elliptica, in summer. In contrast, in Nara park where fewL. elliptica were available, the bug exploited onlyP. japonica. Thus, seasonal host alternation by this bug is not obligate. A comparison of adult longevity and fecundity on the two host-plant species demonstrated the higher quality ofL. elliptica as a food resource. Corresponding to this difference in host quality, there was a dramatic difference in the seasonal population growth in the two study sites. In Nara, the population size at the beginning of the 2nd generation was almost the same as in the overwintered generation, whereas in Kyoto the population size in the 2nd generation was approximately one hundred times as large as in the overwintered generation. Thus seasonal host alternation is adaptive for the bug. In a previous study, I reported that overwintering as eggs in living leaves of their hosts is likely to be common among all the related species of this bug. Thus, this trait can be considered to be a phylogenetic constraint to the group. I speculate that host alternation by this bug has been derived because it is more adaptive from autoecy on an evergreen plant, similar to the pattern currently found in Nara, and that this bug can not only exploit deciduous host due to a phylogenetic constraint.

This paper describes a rare case of inflammatory pseudotumor in the liver. A 54-year-old man was admitted to the hospital because of a middle grade fever and left upper abdominal pain. Erythrocyte sedimentation rate was elevated and C-reactive protein was positive. Abdominal ultrasonography showed a heterogenous but clearly defined low echoic area about 2cm in diameter in the hepatic lateral segment. Abdominal computer tomography (CT) detected a low density area in the same hepatic lateral segment, and the contrast enhanced CT demonstrated a mass lesion composed of low density area with ring-shaped enhancement in its perimeter. We performed partial resection of the hepatic lateral segment and found a well-circumscribed and yellowish tumor of 2cm in diameter in the inferior lateral segment of the left lobe. Histological examination of the tumor verified the presence of plasma cells and inflammatory cells in glanulomatous tissue composed of collagen fibers. From this, the tumor was diagnosed as inflammatory pseudotumor of the liver.

Effects of neurohypophysial hormones on the plasma lipid concentrations were studied in the rat.1. The effect of AVP in decreasing plasma FFA level was less marked than that of LVP. The effect was significantly greater in cold-acclimated rats than in warm-acclimated ones.2. Plasma concentrations of esterified fatty acids and phospholipids were not affected by single injection of LVP and consecutive administrations of Pitressin tannate for 10 days. Similarly, glycerol concentration in the serum was not decreased after injection of vasopressin and oxytocin. Cholesterol was slightly reduced following successive injections of Pitressin tannate.3. Ultracentrifugal analysis of rat serum revealed two fractions of lipoproteins: Sf 3-8 and Sf 70-120. The Sf 70-120 fraction increased following vasopressin injection, while it decreased following oxytocin. The concentrations of Sf 3-8 fraction did not change after administration of the hormones.4. In neurohypophysectomized rats the low-density lipoprotein concentrations were in the normal ranges. The Sf 70-120 fraction disappeared after total hypophysectomy, although Sf 3-8 fraction remained unchanged.

1. Effects of synthetic lysine vasopressin on the plasma concentration of FFA and in vitro oxygen consumption of tissues were studied in the rat.2. The plasma FFA concentration decreased significantly following the injection of vasopressin, while the effect of oxytocin was less marked. Pre-treatment with vasopressin caused a significant suppression on norepinephrine, effect in increasing the plasma FFA concentration.3. In vitro oxygen consumption of liver slices and hemidiaphragms was related to the medium concentration of palmitate.4. In vitro release of FFA by epididymal fat pads was not affected by the addition of vasopressin. FFA releasing effect of norepinephrine was not influenced by the presence of vasopressin.5. In vitro oxygen consumption of brown adipose tissue, liver and diaphragm was significantly reduced by the addition of vasopressin into the incubation medium, while that of white adipose tissue was not affected by vasopressin.

1. The administration of synthetic lysine vasopressin (100 and 40 mU per 100g, i. p.) caused a marked decrease in the metabolic rate in fasted rats. Synthetic oxytocin (400 mU per 100g, i. p.) had no effect.2. The administration of hypertonic sodium chloride solution (2ml per 100g, per os) caused a slight but significantdecrease in the metabolic rate in fasted rats. Chronic administration of 2 per cent sodium chloride solution for 7 days did not show any change in the metabolic rate.3. In sugar administered rats the decrease in the oxygen consumption produced by vasopressin was associated with an elevation of the RQ. In rats with high RQ values exceeding 0.900 the suppressive effect of vasopressin was not observed.4. The calorigenic effect of norepinephrine was entirely abolished by treatment with vasopressin.5. In alloxan diabetic rats the suppressive effect of vasopressin was also observed, though the metabolic rate wasextremely low in these animals.6. The results suggest that vasopressinexhibits its effect on the metabolic rate by suppressing fat utilization as metabolic fuel.