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51.
52.
Male solitary bees typically use emergence‐nesting areas and/or flower patches of food plants, where receptive females are relatively numerous, as rendezvous sites. However, mate‐seeking males have been also observed at food‐deceptive orchid patches, where numerous encounters with foraging females can hardly be expected, owing to the lack of floral rewards. Here, we describe the male mate‐seeking and mating behaviors of the Japanese long‐horned bee Eucera nipponensis at habitats of the food‐deceptive orchid Cymbidium goeringii. On the basis of the results, we report empty flower patches are not necessarily fruitless sites for mate‐seeking males because naive female bees, which are highly likely to be recently emerged and unmated, can be attracted to non‐rewarding orchids. We also suggest a possibility that a small number of the males could receive a “sexual reward” (i.e. mating opportunities), owing to the food‐deceptive orchid, in return for their pollination work. This occasional interaction could represent the initial stage in the evolution of sexually deceptive orchids from food‐deceptive orchids. 相似文献
53.
Koyama Satoshi Fujita Hiroyuki Shimosato Takeshi Kamijo Aki Ishiyama Yasufumi Yamamoto Eri Ishii Yoshimi Hattori Yukako Hagihara Maki Yamazaki Etsuko Tomita Naoto Nakajima Hideaki 《Probiotics and antimicrobial proteins》2019,11(1):295-298
Probiotics and Antimicrobial Proteins - Probiotic-rich foods are consumed without much restriction. We report here, a case of septic shock caused by yogurt derived Lactobacillus species in a... 相似文献
54.
Yuichiro Maeda Toshio Hasegawa Etsuko Komiyama Yusuke Hirasawa Hitoshi Tsuchihashi Takasuke Ogawa Jonghun Kim Seiichiro Ando Akio Nagasaka Naoto Miura Shigaku Ikeda 《Journal of biophotonics》2019,12(4)
In finger vein authentication technology, near‐infrared rays penetrate the finger and are absorbed by the hemoglobin in blood. The veins appear as dark areas. The finger vein pattern images of patients with various diseases were acquired; a new evaluation method applying image processing technique (“E value”) was developed, and it was examined whether the patterns have any characteristics differentiating them from those of healthy volunteers. As a result, low E values appeared in systemic sclerosis, mixed connective tissue disease, Sjögren's syndrome, and polymyositis/dermatomyositis. No statistical reduction in E value was shown in patients with rheumatoid arthritis, pernio (without rheumatic diseases), arteriosclerosis obliterans, diabetes, hypertension, hypothyroidism and alopecia areata. This technology could be used for screening and evaluation of some diseases and their conditions with impaired peripheral venous circulation. E value may be useful as an indicator of venous circulation. 相似文献
55.
Pre-term birth is the leading cause of perinatal and neonatal mortality, 40% of which are attributed to the pre-term premature rupture of amnion. Rupture of amnion is thought to be associated with a corresponding decrease in the extracellular collagen content and/or increase in collagenase activity. However, there is very little information concerning the detailed organisation of fibrillar collagen in amnion and how this might influence rupture. Here we identify a loss of lattice like arrangement in collagen organisation from areas near to the rupture site, and present a 9% increase in fibril spacing and a 50% decrease in fibrillar organisation using quantitative measurements gained by transmission electron microscopy and the novel application of synchrotron X-ray diffraction. These data provide an accurate insight into the biomechanical process of amnion rupture and highlight X-ray diffraction as a new and powerful tool in our understanding of this process. 相似文献
56.
Lipopolysaccharide enhances the production of nicotine-induced prostaglandin E2 by an increase in cyclooxygenase-2 expression in osteoblasts 总被引:5,自引:0,他引:5
Shoji M Tanabe N Mitsui N Suzuki N Takeichi O Katono T Morozumi A Maeno M 《Acta biochimica et biophysica Sinica》2007,39(3):163-172
Previous studies have indicated that lipopolysaccharide(LPS)from Gram-negative bacteria inplaque induces the release of prostaglandin E_2(PGE_2),which promotes alveolar bone resorption in periodontitis,and that tobacco smoking might be an important risk factor for the development and severity of periodontitis.We determined the effect of nicotine and LPS on alkaline phosphatase(ALPase)activity,PGE_2 production,and the expression of cyclooxygenase(COX-1,COX-2),PGE_2 receptors Ep1-4,and macrophage colonystimulating factor(M-CSF)in human osteoblastic Saos-2 cells.The cells were cultured with 10~(-3)M nicotinein the presence of 0,1,or 10μg/ml LPS,or with LPS alone.ALPase activity decreased in cells cultured withnicotine or LPS alone,and decreased further in those cultured with both nicotine and LPS,whereas PGE_2production significantly increased in the former and increased further in the latter.By itself,nicotine did notaffect expression of COX-1,COX-2,any of the PGE_2 receptors,or M-CSF,but when both nicotine and LPSwere present,expression of COX-2,Ep3,Ep4,and M-CSF increased significantly.Simultaneous addition of10~(-4)M indomethacin eliminated the effects of nicotine and LPS on ALPase activity,PGE_2 production,and M-CSF expression.Phosphorylation of protein kinase A was high in cells cultured with nicotine and LPS.Theseresults suggest that LPS enhances the production of nicotine-induced PGE_2 by an increase in COX-2 expres-sion in osteoblasts,that nicotine-LPS-induced PGE_2 interacts with the osteoblast Ep4 receptor primarily inautocrine or paracrine mode,and that the nicotine-LPS-induced PGE_2 then decreases ALPase activity andincreases M-CSF expression. 相似文献
57.
Tanida Kotomi Shimada Mihoko Khor Seik-Soon Toyoda Hiromi Kato Kayoko Kotorii Nozomu Kotorii Tatayu Ariyoshi Yu Kato Takao Hiejima Hiroshi Ozone Motohiro Uchimura Naohisa Ikegami Azusa Kume Kazuhiko Kanbayashi Takashi Imanishi Aya Kamei Yuichi Hida Akiko Wada Yamato Kuroda Kenji Miyamoto Masayuki Hirata Koichi Takami Masanori Yamada Naoto Okawa Masako Omata Naoto Kondo Hideaki Kodama Tohru Inoue Yuichi Mishima Kazuo Honda Makoto Tokunaga Katsushi Miyagawa Taku 《Sleep and biological rhythms》2022,20(1):137-148
Sleep and Biological Rhythms - Idiopathic hypersomnia (IH) is a rare sleep disorder characterized by excessive daytime sleepiness, great difficulty upon awakening, and prolonged sleep time. In... 相似文献
58.
Shoji Kawauchi Sayo Horibe Naoto Sasaki Ken-ichi Hirata Yoshiyuki Rikitake 《Experimental cell research》2019,374(2):333-341
Here, we developed a novel in vitro co-culture model, in which process-bearing astrocytes and isolated cerebral microvessels from mice were co-cultured. Astrocytes formed contacts with microvessels from both adult and neonatal mice. However, concentrated localization of the immunofluorescence signal for aquaporin-4 (AQP4) at contact sites between perivascular endfoot processes and blood vessels was only detected with neonatal mouse microvessels. Contact between astrocytic processes and microvessels was retained, whereas concentrated localization of AQP4 signal at contact sites was lost, by knockdown of dystroglycan or α-syntrophin, reflecting polarized localization of AQP4 at perivascular regions in the brain. Further, using our in vitro co-culture model, we found that astrocytes predominantly extend processes to pericytes located at the abluminal surface of microvessels, providing additional evidence that this model is representative of the in vivo situation. Altogether, we have developed a novel in vitro co-culture model that can reproduce aspects of the in vivo situation and is useful for assessing contact formation between astrocytes and blood vessels. 相似文献
59.
A simple chiral analysis of amino acid esters by fluorine‐19 nuclear magnetic resonance (19F NMR) through the modified James–Bull method is described. Thus, amino acid ester acid salt was treated with 5‐fluoro‐2‐formylphenylboronic acid and (S)‐BINOL in the presence of triethylamine (TEA) and MS4A for 10 minutes. The reaction mixture was analysed by 19F NMR directly to afford good quantifications. 相似文献
60.
Lysine decarboxylase (LDC, EC 4.1.1.18) from Selenomonas ruminantium has decarboxylating activities towards both L-lysine and L-ornithine with similar K(m) and Vmax. Here, we identified four amino acid residues that confer substrate specificity upon S. ruminantium LDC and that are located in its catalytic domain. We have succeeded in converting S. ruminantium LDC to an enzyme with a preference in decarboxylating activity for L-ornithine when the four-residue of LDC were replaced by the corresponding residues of mouse ornithine decarboxylase (EC 4.1.1.17). 相似文献