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71.
Ai Sasou Takanari Shigemitsu Yuhi Saito Manami Tanaka Shigeto Morita Takehiro Masumura 《Plant cell reports》2016,35(6):1287-1295
Key message
Prolamin–GFP fusion proteins, expressed under the control of native prolamin promoters, were localized in specific layers of PB-Is. Prolamin–GFP fusion proteins were gradually digested from outside by pepsin digestion.Abstract
In rice seed endosperm, protein body type I (PB-I) has a layered structure consisting of prolamin species and is the resistant to digestive juices in the intestinal tract. We propose the utilization of PB-Is as an oral vaccine carrier to induce mucosal immune response effectively. If vaccine antigens are localized in a specific layer within PB-Is, they could be protected from gastric juice and be delivered intact to the small intestine. We observed the localization of GFP fluorescence in transgenic rice endosperm expressing prolamin–GFP fusion proteins with native prolamin promoters, and we confirmed that the foreign proteins were located in specific layers of PB-Is artificially. Each prolamin–GFP fusion protein was localized in specific layers of PB-Is, such as the outer-most layer, middle layer, and core region. Furthermore, to investigate the resistance of prolamin–GFP fusion proteins against pepsin digestion, we performed in vitro pepsin treatment. Prolamin–GFP fusion proteins were gradually digested from the peripheral region and the contours of PB-Is were made rough by in vitro pepsin treatment. These findings suggested that prolamin–GFP fusion proteins accumulating specific layers of PB-Is were gradually digested and exposed from the outside by pepsin digestion.72.
Spatial and temporal variations in major phytoplankton populations such as diatoms in the changing Arctic Ocean have been well studied, whereas only a few monitoring studies have been conducted on minor siliceous flagellates. To discern the relationship between hydrographic conditions and the spatio-temporal distribution of silicoflagellates, ebridians, and the endoskeletal dinoflagellate Actiniscus pentasterias, we analyzed seawater and bottom-tethered sediment-trap samples from the western Arctic Ocean. Silicoflagellates and ebridians were commonly observed in shelf waters around the southern Chukchi Sea in September–October during 2010 and 2013. However, one mesoscale patch with abundant silicoflagellates and ebridians was observed in the southwestern Canada Basin during September–October 2010. This offshore patch reflected an unusual occurrence of a mesoscale eddy deriving from the Alaskan Coastal Water. The active lateral transport of shelf materials by eddies was also evident in high silicoflagellate and ebridian fluxes at station Northwind Abyssal Plain (NAP) (75°N, 162°W, 1975-m water depth) in November–December during 2010 and 2011. The summer silicoflagellate flux at station NAP was mainly composed of Distephanus speculum. During the sea-ice cover period, except for July, silicoflagellates D. medianoctisol and D. octonarius were relatively abundant in the assemblage. The spike in D. speculum flux during July 2011 was observed with fecal pellets containing abundant silicoflagellates, suggesting a temporal silicoflagellate contribution to some kinds of zooplankton. The common occurrence of A. pentasterias in settling particles at station NAP during the winter may indicate their tolerance to cold water under sea ice. 相似文献
73.
Kazuko Omodaka Seri Takahashi Akiko Matsumoto Shigeto Maekawa Tsutomu Kikawa Noriko Himori Hidetoshi Takahashi Kazuichi Maruyama Hiroshi Kunikata Masahiro Akiba Toru Nakazawa 《PloS one》2016,11(4)
PurposeTo investigate the influence of various risk factors on thinning of the lamina cribrosa (LC), as measured with swept-source optical coherence tomography (SS-OCT; Topcon).MethodsThis retrospective study comprised 150 eyes of 150 patients: 22 normal subjects, 28 preperimetric glaucoma (PPG) patients, and 100 open-angle glaucoma patients. Average LC thickness was determined in a 3 x 3 mm cube scan of the optic disc, over which a 4 x 4 grid of 16 points was superimposed (interpoint distance: 175 μm), centered on the circular Bruch’s membrane opening. The borders of the LC were defined as the visible limits of the LC pores. The correlation of LC thickness with Humphrey field analyzer-measured mean deviation (MD; SITA standard 24–2), circumpapillary retinal nerve fiber layer thickness (cpRNFLT), the vertical cup-to-disc (C/D) ratio, and tissue mean blur rate (MBR) was determined with Spearman''s rank correlation coefficient. The relationship of LC thickness with age, axial length, intraocular pressure (IOP), MD, the vertical C/D ratio, central corneal thickness (CCT), and tissue MBR was determined with multiple regression analysis. Average LC thickness and the correlation between LC thickness and MD were compared in patients with the glaucomatous enlargement (GE) optic disc type and those with non-GE disc types, as classified with Nicolela’s method.ResultsWe found that average LC thickness in the 16 grid points was significantly associated with overall LC thickness (r = 0.77, P < 0.001). The measurement time for this area was 12.4 ± 2.4 minutes. Average LC thickness in this area had a correlation coefficient of 0.57 with cpRNFLT (P < 0.001) and 0.46 (P < 0.001) with MD. Average LC thickness differed significantly between the groups (normal: 268 ± 23 μm, PPG: 248 ± 13 μm, OAG: 233 ± 20 μm). Multiple regression analysis showed that MD (β = 0.29, P = 0.013), vertical C/D ratio (β = -0.25, P = 0.020) and tissue MBR (β = 0.20, P = 0.034) were independent variables significantly affecting LC thickness, but age, axial length, IOP, and CCT were not. LC thickness was significantly lower in the GE patients (233.9 ± 17.3 μm) than the non-GE patients (243.6 ± 19.5 μm, P = 0.040). The correlation coefficient between MD and LC thickness was 0.58 (P < 0.001) in the GE patients and 0.39 (P = 0.013) in the non-GE patients.ConclusionCupping formation and tissue blood flow were independently correlated to LC thinning. Glaucoma patients with the GE disc type, who predominantly have large cupping, had lower LC thickness even with similar glaucoma severity. 相似文献
74.
Yoshitaka Ishimuro Saburo Yamaguchi Fumiyuki Hamada Akio Nakajima 《Biopolymers》1981,20(12):2499-2508
Small-angle x-ray scattering of poly(γ-methyl-L -glutamate), [Glu(OMe)]n, in m-cresol and in pyridine was measured to determine the mass per unit length, Mq, and the radius of gyration of the cross section, 〈S〉1/2. It was confirmed from the values of Mq that [Glu(OMe)]n exists in an α-helical conformation in these solvents. It was elucidated from the calculations on 〈S〉1/2 that the side chains come in moderately close contact with the main chain in these solvents. It was indicated from the analysis of the outer portion of the scattering curves that the side-chain conformation varied depending on the solvent. 相似文献
75.
Kazuhiko Yamagami Shigeto Nishimura Masaru Sorimachi 《Journal of neurochemistry》1991,57(5):1681-1689
The cytosolic free Ca2+ concentration ([Ca2+]in) in single cat and bovine adrenal chromaffin cells was measured to determine whether or not there was any correlation between the [Ca2+]in and the catecholamine (CA) secretion caused by muscarinic receptor stimulation. In cat chromaffin cells, methacholine (MCh), a muscarinic agonist, raised [Ca2+]in by activating both Ca2+ influx and intracellular Ca2+ mobilization with an accompanying CA secretion. In bovine cells, MCh elevated [Ca2+]in by mobilizing intracellular Ca2+ but did not cause CA secretion. The MCh-induced rise in [Ca2+]in in cat cells was much higher than that in bovine cells, but when Ca2+ influx was blocked, the rise was reduced, with a concomitant loss of secretion, to a level comparable to that in bovine cells. Intracellular Ca2+ mobilization due to muscarinic stimulation substantially increased secretion from depolarized bovine and cat cells, where a [Ca2+]in elevated above basal values was maintained by a continuous Ca2+ influx. These results show that Ca2+ released from internal stores is not effective in triggering secretion unless Ca2+ continues to enter across the plasma membrane, a conclusion suggesting that secretion depends on [Ca2+]in in a particular region of the cell. 相似文献
76.
Glenn Gladys M. Daniel Lambert N. Choyke Peter Linehan W. Marston Oldfield Edward Gorin Michael B. Hosoe Shigeto Latif Farida Weiss Gary Walther McClellan Lerman Michael I. Zbar Berton 《Human genetics》1991,87(2):207-210
Summary As part of an attempt to locate the von Hippel-Lindau locus (VHL) on chromosome 3, we evaluated 41 families with von Hippel-Lindau disease from the United States and Canada. One large family was identified whose disease phenotype was distinct from typical VHL. The most common disease manifestation was pheochromocytoma occuring in 57% (27/47) of affected family members. Few (4/47) affected family members had symptomatic spinal or cerebellar hemangioblastomas; no affected family member had renal cell carcinoma (0/47) or pancreatic cysts (0/24). Previously, genetic analysis demonstrated that the disease manifestations in this family were linked to RAF1 and D3S18, markers shown to be linked to typical VHL. These results suggest that there are mutant alleles at the VHL locus associated with distinct tissue specificities. 相似文献
77.
In Vivo Determination of 5-Hydroxytryptamine Receptor-Stimulated Phosphoinositide Turnover in Rat Brain 总被引:2,自引:2,他引:0
Phosphoinositide turnover stimulated by 5-hydroxytryptamine (5-HT) receptors in the intact rat brain was studied using an in vivo method. Phosphoinositides in the rat brain were prelabeled with [3H]inositol injected into the lateral cerebral ventricles. The rats were killed by microwave irradiation after 48 h and the contents in the frontal cortex of 3H-inositol phosphates, [3H]inositol-1-monophosphate [( 3H]IP1), [3H]inositol-1,4-bisphosphate [( 3H]IP2), and a mixture of [3H]inositol-1,4,5-trisphosphate and [3H]inositol-1,3,4-trisphosphate [( 3H]IP3) were assayed by HPLC. Lithium treatment (10 mEq/kg, i.p., 2 h before) increased the content of [3H]IP1 and [3H]IP2. 5-Methoxy-N,N-dimethyltryptamine (5-MeODMT) and quipazine, 5-HT agonists, significantly increased the amount of 3H-inositol phosphates under lithium pretreatment. The response to 5-MeODMT was inhibited by ritanserin, a 5-HT2 antagonist, but not by (-)-propranolol, a 5-HT1 antagonist. These results suggest that phosphoinositide turnover in the rat frontal cortex in vivo is stimulated by 5-HT2 receptor activation. It is considered that this method will be useful for measurement of 5-HT2 receptor-stimulated phosphoinositide turnover in vivo to examine the in vivo effects of various psychotropic drugs such as antidepressants. 相似文献
78.
Shinpei Yoshimura Yasumasa Okamoto Atsuo Yoshino Makoto Kobayakawa Akihiko Machino Shigeto Yamawaki 《PloS one》2014,9(7)
Reappraisal is a well-known emotion regulation strategy. Recent neuroimaging studies suggest that reappraisal recruits both medial and lateral prefrontal brain regions. However, few studies have investigated neural representation of reappraisals associated with anticipatory anxiety, and the specific nature of the brain activity underlying this process remains unclear. We used functional magnetic resonance imaging (fMRI) to investigate neural activity associated with reappraisals of transient anticipatory anxiety. Although transient anxiety activated mainly subcortical regions, reappraisals targeting the anxiety were associated with increased activity in the medial and lateral prefrontal regions (including the orbitofrontal and anterior cingulate cortices). Reappraisal decreased fear circuit activity (including the amygdala and thalamus). Correlational analysis demonstrated that reductions in subjective anxiety associated with reappraisal were correlated with orbitofrontal and anterior cingulate cortex activation. Reappraisal recruits medial and lateral prefrontal regions; particularly the orbitofrontal and anterior cingulate cortices are associated with successful use of this emotion regulation strategy. 相似文献
79.
Yoshida S Shimada Y Kondoh D Kouzuma Y Ghosh AK Jacobs-Lorena M Sinden RE 《PLoS pathogens》2007,3(12):e192
The midgut environment of anopheline mosquitoes plays an important role in the development of the malaria parasite. Using genetic manipulation of anopheline mosquitoes to change the environment in the mosquito midgut may inhibit development of the malaria parasite, thus blocking malaria transmission. Here we generate transgenic Anopheles stephensi mosquitoes that express the C-type lectin CEL-III from the sea cucumber, Cucumaria echinata, in a midgut-specific manner. CEL-III has strong and rapid hemolytic activity toward human and rat erythrocytes in the presence of serum. Importantly, CEL-III binds to ookinetes, leading to strong inhibition of ookinete formation in vitro with an IC(50) of 15 nM. Thus, CEL-III exhibits not only hemolytic activity but also cytotoxicity toward ookinetes. In these transgenic mosquitoes, sporogonic development of Plasmodium berghei is severely impaired. Moderate, but significant inhibition was found against Plasmodium falciparum. To our knowledge, this is the first demonstration of stably engineered anophelines that affect the Plasmodium transmission dynamics of human malaria. Although our laboratory-based research does not have immediate applications to block natural malaria transmission, these findings have significant implications for the generation of refractory mosquitoes to all species of human Plasmodium and elucidation of mosquito-parasite interactions. 相似文献
80.
Nagase H Akiyama J Nakajima R Hirayama S Nemoto T Gouda H Hirono S Fujii H 《Bioorganic & medicinal chemistry letters》2012,22(8):2775-2779
We designed and synthesized propellane derivatives with a 6- or 7-amide side chain on the basis of the active conformation of the κ selective agonist nalfurafine. The 6-amides showed high affinities for the κ receptor, and one of the 6β-amides showed higher κ selectivity than nalfurafine. On the other hand, although the affinities of the 7-amides decreased compared to the 6-amides, some 7α-amides showed the highest selectivities for the κ receptor among the tested compounds. The affinities of 7β-isomers were extremely low, which was postulated to result from the shielding effect of the 7β-amide side chain against the lone electron pair on the 17-nitrogen. This is the first conformational information about the 7-amide side chain in propellane derivatives. 相似文献