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排序方式: 共有414条查询结果,搜索用时 31 毫秒
1.
A Araya M Krauskopf M A Siddiqui 《Biochemical and biophysical research communications》1975,67(3):924-934
Transfer RNA with methionine acceptor activity isolated from two distinct physiological stages of the developing posterior silkgland of the silkworm, , was examined. The tRNA from both stages could be fractionated on benzoylated DEAE-cellulose colum into two iso-accepting species, tRNA1Met and tRNA2Met. The molar quantity per gland of tRNA1Met species, which was also formylatable with the enzymes, increased twelve-fold as the gland differentiates to produce a large amount of a single protein, silk-fibroin. Since methionine is not a part of silk-fibroin, the preferential increase in tRNA1Met content would reflect the increased biological activity and the rapid rate of protein synthesis during the terminal differentiation of posterior silkgland. 相似文献
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Takuji Tachi Yu-Zen Huang Shin Komagata Kunio Araya Mahadimenakbar Mohamed Dawood Thai Hong Pham Ding Yang Theo Zeegers Hans-Peter Tschorsnig Hiroshi Shima 《Journal of Asia》2021,24(1):285-296
Compsilura concinnata (Meigen) is one of the most famous, most polyphagous and most widely distributed tachinid flies (Diptera, Tachinidae) in the world. This species is well known as a biocontrol agent of some injurious pests of cultural and wild plants and has been introduced from Europe to the United States to control mainly the gypsy moth. Recently we found three new species very closely resembling C. concinnata from Southeast and East Asia: C. lobata sp. nov. (Japan and Thailand), C. malayana sp. nov. (Malaysia) and C. pauciseta sp. nov. (Japan and Taiwan). Additionally, C. samoaensis Malloch is treated as a junior synonym of C. concinnata based on the examination of the type specimen. The genetic differences in the mitochondrial COI gene data are examined to assess the accuracy of species delimitation of Compsilura. The male postabdominal characters of these species are illustrated. The piercing female postabdomen of C. concinnata is illustrated and compared to those of other members belonging to the Blondelia group including Blondelia Robineau-Desvoidy, Celatoria Coquillett, Eucelatoria Townsend and Vibrissina Rondani. 相似文献
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Braulio A. Assis Julian D. Avery Catherine Tylan Heather I. Engler Ryan L. Earley Tracy Langkilde 《Ecology and evolution》2021,11(12):7647
Sex differences in animal coloration often result from sex‐dependent regulatory mechanisms. Still, some species exhibit incomplete sexual dimorphism as females carry a rudimentary version of a costly male trait, leading to intralocus sexual conflict. The underlying physiology and condition dependence of these traits can inform why such conflicts remain unresolved. In eastern fence lizards (Sceloporus undulatus), blue iridophore badges are found in males and females, but melanin pigmentation underneath and surrounding badges is male‐exclusive. We track color saturation and area of badges across sexual maturity, and their relationship to individual quality (body condition and immunocompetence) and relevant hormones (testosterone and corticosterone). Saturation and testosterone were positively correlated in both sexes, but hormone and trait had little overlap between males and females. Saturation was correlated with body condition and immunocompetence in males but not in females. Co‐regulation by androgens may have released females from resource allocation costs of color saturation, even when in high condition. Badge area was independent of testosterone, but associated with low corticosterone in females, indicating that a nonsex hormone underlies incomplete sexual dimorphism. Given the evidence in this species for female reproductive costs associated with ornamentation, this sex‐nonspecific regulation of an honest signal may underlie intralocus sexual conflict. 相似文献
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Jun Kojima Jun Araya Hiromichi Hara Saburo Ito Naoki Takasaka Kenji Kobayashi Satoko Fujii Chikako Tsurushige Takanori Numata Takeo Ishikawa Kenichiro Shimizu Makoto Kawaishi Keisuke Saito Noriki Kamiya Jun Hirano Makoto Odaka Toshiaki Morikawa Hiroshi Hano Satoko Arai Toru Miyazaki Yumi Kaneko Katsutoshi Nakayama Kazuyoshi Kuwano 《Respiratory research》2013,14(1):30
Background
Marked accumulation of alveolar macrophages (AM) conferred by apoptosis resistance has been implicated in pathogenesis of chronic obstructive pulmonary disease (COPD). Apoptosis inhibitor of macrophage (AIM), has been shown to be produced by mature tissue macrophages and AIM demonstrates anti-apoptotic property against multiple apoptosis-inducing stimuli. Accordingly, we attempt to determine if AIM is expressed in AM and whether AIM is involved in the regulation of apoptosis in the setting of cigarette smoke extract (CSE) exposure.Methods
Immunohistochemical evaluations of AIM were performed. Immunostaining was assessed by counting total and positively staining AM numbers in each case (n = 5 in control, n = 5 in non-COPD smoker, n = 5 in COPD). AM were isolated from bronchoalveolar lavage fluid (BALF). The changes of AIM expression levels in response to CSE exposure in AM were evaluated. Knock-down of anti-apoptotic Bcl-xL was mediated by siRNA transfection. U937 monocyte-macrophage cell line was used to explore the anti-apoptotic properties of AIM.Results
The numbers of AM and AIM-positive AM were significantly increased in COPD lungs. AIM expression was demonstrated at both mRNA and protein levels in isolated AM, which was enhanced in response to CSE exposure. AIM significantly increased Bcl-xL expression levels in AM and Bcl-xL was involved in a part of anti-apoptotic mechanisms of AIM in U937 cells in the setting of CSE exposure.Conclusions
These results suggest that AIM expression in association with cigarette smoking may be involved in accumulation of AM in COPD. 相似文献8.
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Muichi Kaito Shin-Ichi Araya Yuichiro Gondo Michiyo Fujita Naomi Minato Megumi Nakanishi Makoto Matsui 《PloS one》2013,8(8)
Background and Purpose
The most common strategy for treating patients with acute ischemic stroke is thrombolytic therapy, though only a few patients receive benefits because of the narrow time window. Inflammation occurring in the central nervous system (CNS) in association with ischemia is caused by immune cells including monocytes and involved in lesion expansion. If the specific roles of monocyte subsets in stroke can be revealed, they may become an effective target for new treatment strategies.Methods
We performed immunological examinations of 36 consecutive ischemic stroke patients within 2 days of onset and compared the results with 24 age-matched patients with degenerative disorders. The stroke patients were repeatedly tested for the proportions of monocyte subsets in blood, and serum levels of pro- and anti-inflammatory cytokines immediately after admission, on days 3-7 and 12-16 after stroke onset, and on the day of discharge. In addition, immunological measurements were analyzed for relationships to stroke subtypes and complications, including progressive infarction (PI) and stroke-associated infection (SAI).Results
Monocyte count was significantly increased from 0–16 days after stroke as compared to the controls (p<0.05). CD14highCD16- classical and CD14highCD16+ intermediate monocytes were significantly increased from 0-7 and 3-16 days after stroke, respectively (p<0.05), whereas CD14 dimCD16high non-classical monocytes were decreased from 0–7 days (p<0.05). Cardioembolic infarction was associated with a persistent increase in intermediate monocytes. Furthermore, intermediate monocytes were significantly increased in patients with PI (p<0.05), while non-classical monocytes were decreased in those with SAI (p<0.05). IL-17A levels were positively correlated with monocyte count (r=0.485, p=0.012) as well as the percentage of non-classical monocytes (r=0.423, p=0.028), and negatively with that of classical monocytes (r=-0.51, p=0.007) during days 12-16.Conclusions
Our findings suggest that CD14highCD16+ intermediate monocytes have a role in CNS tissue damage during acute and subacute phases in ischemic stroke especially in relation to cardioembolism. 相似文献10.
Clare E Buckley Xiaoyun Ren Laura C Ward Gemma C Girdler Claudio Araya Mary J Green Brian S Clark Brian A Link Jonathan D W Clarke 《The EMBO journal》2013,32(1):30-44
By analysing the cellular and subcellular events that occur in the centre of the developing zebrafish neural rod, we have uncovered a novel mechanism of cell polarisation during lumen formation. Cells from each side of the neural rod interdigitate across the tissue midline. This is necessary for localisation of apical junctional proteins to the region where cells intersect the tissue midline. Cells assemble a mirror‐symmetric microtubule cytoskeleton around the tissue midline, which is necessary for the trafficking of proteins required for normal lumen formation, such as partitioning defective 3 and Rab11a to this point. This occurs in advance and is independent of the midline cell division that has been shown to have a powerful role in lumen organisation. To our knowledge, this is the first example of the initiation of apical polarisation part way along the length of a cell, rather than at a cell extremity. Although the midline division is not necessary for apical polarisation, it confers a morphogenetic advantage by efficiently eliminating cellular processes that would otherwise bridge the developing lumen. 相似文献