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31.
32.
Hoang Viet Nguyen Emi Suzuki Zachery Oestreicher Hiroshi Minamide Hiroshi Endoh Yoshihiro Fukumori Azuma Taoka 《Biochemistry and Biophysics Reports》2016
Magnetosomes are membrane-enveloped bacterial organelles containing nano-sized magnetic particles, and function as a cellular magnetic sensor, which assist the cells to navigate and swim along the geomagnetic field. Localized with each magnetosome is a suite of proteins involved in the synthesis, maintenance and functionalization of the organelle, however the detailed molecular organization of the proteins in magnetosomes is unresolved. MamA is one of the most abundant magnetosome-associated proteins and is anchored to the magnetosome vesicles through protein-protein interactions, but the identity of the protein that interacts with MamA is undetermined. In this study, we found that MamA binds to a magnetosome membrane protein Mms6. Two different molecular masses of Mms6, 14.5-kDa and 6.0-kDa, were associated with the magnetosomes. Using affinity chromatography, we identified that the 14.5-kDa Mms6 interacts with MamA, and the interaction was further confirmed by pull-down, immunoprecipitation and size-exclusion chromatography assays. Prior to this, Mms6 was assumed to be strictly involved with biomineralizing magnetite; however, these results suggest that Mms6 has an additional responsibility, binding to MamA. 相似文献
33.
Yoichiro?OkuboEmail author Osamu?Motohashi Norisuke?Nakayama Ken?Nishimura Rika?Kasajima Yohei?Miyagi Manabu?Shiozawa Emi?Yoshioka Masaki?Suzuki Kota?Washimi Kae?Kawachi Madoka?Nito Yoichi?Kameda Tomoyuki?Yokose 《Diagnostic pathology》2016,11(1):128
Background
As the World Health Organization grading system for gastroenteropancreatic-neuroendocrine tumors (GEP-NETs) may not always correlate with tumor progression, it is imperative that other independent predictors of tumor progression be established. To identify such predictors, we conducted a retrospective histopathological study of hindgut NETs, obtained from endoscopic procedures, and used statistical analyses to evaluate predictive factors.Methods
We first obtained clinicopathological data of cases of hindgut NETs. Tissue sections from tumor samples were prepared and subjected to pathological examination. In particular, we calculated the microvessel density (MVD) and lymphatic microvessel density (LMVD) values, and performed appropriate statistical analyses.Results
A total of 42 cases of hindgut NETs were selected for the study, 41 from the rectum and 1 from the sigmoid colon. Based on the Ki-67 labeling index, 34 cases were classified as NET G1 tumors and 8 as NET G2 tumors. MVD values ranged from 1.4/mm2 to 73.9/mm2 and LMVD values from 0/mm2 to 22.9/mm2. MVD and LMVD were identified as risk factors for venous and lymphatic invasion of hindgut NETs. Moreover, MVD positively correlated with the maximum diameter of the tumor.Conclusions
Tumor progression of NETs may cause angiogenesis and lymphangiogenesis, via an unknown mechanism, as well as lymphovascular invasion. Angiogenesis likely plays an important role in occurrence and progression in the initial phase of hindgut NETs.34.
Junichiro Kishi Shinsuke Inuki Natsumi Hirata Emi Kashiwabara Daisuke Yoshidome Osamu Ichihara Yukari Fujimoto 《Bioorganic & medicinal chemistry letters》2019,29(8):970-973
Abstract
CD1d is a non-polymorphic antigen-presenting glycoprotein that recognizes glycolipids as ligands. Ligands bind to the hydrophobic grooves of CD1d, and the resulting ligand-CD1d complexes activate natural killer T (NKT) cells by means of T cell receptor recognition, leading to the secretion of various cytokines. However, details of the ligand recognition mechanism of a large hydrophobic ligand binding pocket and the relationship between cytokine induction and ligand structure are unclear. We report the synthesis of α-GalCer derivatives containing a Bz amide group having various substituting groups in the ceramide moiety, and the analysis of the structure-activity relationships. The assays reveal that the Bz amide-containing CD1d ligands function as NKT cell modulators displaying Th2 cytokine biasing responses. Furthermore, molecular dynamics simulation studies suggest that the phenyl groups can interact with the aromatic amino acid residues in the lipid binding pocket of CD1d. 相似文献35.
Naoki Yokokawa Emi Kikuchi‐Uehara Eri Amasawa Hirokazu Sugiyama Masahiko Hirao 《Journal of Industrial Ecology》2019,23(5):1253-1263
This study analyzed the environmental impacts of packaging‐derived changes in food production and consumer behavior to assist packaging designers in making environmentally conscious decisions. Packaging can be functionalized to prevent food loss and waste (FLW), for example, extending the expiration date and apportioning the package size, but it can generate additional environmental impacts from changes in food and packaging production. Previous studies assessed additional impacts from packaging production; however, the effects of packaging functionalization are yet to be connected with food production and consumer behavior. To examine the effect of functionalization on these aspects, we analyzed packaging‐derived changes in food production for milk and cabbage products. The case study compared products with functionalized packaging that permits a longer expiration date or a smaller portion size to their base‐case products. Our results showed that the packaging‐derived changes increased the global warming potential (GWP) of food production more than other processes did. Thus, changes in food production weakened the effectiveness of the packaging functionalization to decrease the GWP. Moreover, the analysis of consumer behavior scenarios showed that consumers’ perception of the expiration date decisively influences the effectiveness of packaging functionalization. When consumers discarded food after the expiration date, provided they consumed in small quantities, the packaging functionalization reduced FLW. From the scenario analysis, we identified appropriate combinations of packaging functionalization and consumer behaviors to effectively decrease total GWP. With our expanded analysis, packaging designers can understand the effectiveness of their decisions on the product life cycle in reducing FLW and environmental impacts. 相似文献
36.
The human salivary amylase gene (amy1), consisting of eleven exons, is expressed in the salivary gland and in some amylase-producing tumors. Its uppermost exon and the following intron, along with the 5'-flanking region of this gene, are shown to be superimposed with a gamma-actin pseudogene sequence, a portion of which is transcribed into salivary amylase mRNA and another portion of which serves as a promoter for the amy1 gene. In the further upstream region, the gamma-actin pseudogene sequence is interrupted by a human endogenous retroviral nucleotide sequence. 相似文献
37.
The echinoid, Asthenosoma ijimai belonging to the order Echinothurioida from Japanese waters shows the geographical variation in morphological and ecological characters. The echinothurioid from Ryukyu Islands in southern Japan is cleary different from that of Sagami Bay and Suruga Bay in the middle part of Japan at non-molecular level.Their phylogenetic and taxonomic relationships were studied at the molecular level by allozyme analysis. The results demonstrated that the two echinothurioids from Ryukyu Islands and Sagami Bay do not share gene pools with each other, and they were fixed for different alleles at five genetic loci (Mdh, G6pd, Po, Alk-3 and Est-7) in a total of 23 enzyme genetic loci scored. This indicates no gene flow between the two echinothurioids, and is a molecular evidence for that they are reproductively isolated and genetically distinct species. The Nei's genetic distance (D=0.181) between the two were significantly higher than those between conspecific local populations, and comparable to those between closely related species in many other animals containing echinoderms. The present molecular data are well consistent with the non-molecular evidence from morphology, developmental biology and ecology. Putting these data together, we propose that the two echinothurioids should be classified as two sibling species of the genus Asthenosoma and would like to give the following scientific names: the echinothurioid species from Sagami Bay is Asthenosoma ijimai and that from Ryukyu Islands is A. ijimai R. 相似文献
38.
Yasuda S Wu PS Hattori E Tachibana H Yamada K 《Bioscience, biotechnology, and biochemistry》2004,68(1):51-58
A method for simultaneous detection and quantification is presented to determine the presence of isoflavones and bisphenol A in a biological sample. A coulometric array detector was used with reversed-phase high-performance liquid chromatography (HPLC). Daidzein (1), glycitein (2), genistein (3) and their glucoside conjugates, daidzin (4), glycitin (5) and genistin (6), were measured as phytochemicals. Also assayed here was equol (7), a metabolite from compound 1, and bisphenol A (8), an industrial chemical that acts as an endocrine disrupter. All chemicals were simultaneously detected by using a 600-mV single detection voltage with high efficacy. A mixture of 1, 3 and 8 was orally administered to rats, and the levels of these three chemicals in the serum were clearly increased after a 4 kU beta-glucuronidase treatment. The levels of compounds 1 and 3 in the serum were detected at 1665 and 2040 ng/ml, while 8 was at a low level of 417 ng/ml. Compound 7 in the serum was not detected until after enzymatic hydrolysis (72 ng/ml). These results suggest that this analytical method would be useful for metabolic and pharmacokinetic studies on isoflavones and bisphenol A. 相似文献
39.
Synergistic interaction of three ERECTA-family receptor-like kinases controls Arabidopsis organ growth and flower development by promoting cell proliferation 总被引:10,自引:0,他引:10
Growth of plant organs relies on coordinated cell proliferation followed by cell growth, but the nature of the cell-cell signal that specifies organ size remains elusive. The Arabidopsis receptor-like kinase (RLK) ERECTA regulates inflorescence architecture. Our previous study using a dominant-negative fragment of ERECTA revealed the presence of redundancy in the ERECTA-mediated signal transduction pathway. Here, we report that Arabidopsis ERL1 and ERL2, two functional paralogs of ERECTA, play redundant but unique roles in a part of the ERECTA signaling pathway, and that synergistic interaction of three ERECTA-family RLKs define aerial organ size. Although erl1 and erl2 mutations conferred no detectable phenotype, they enhanced erecta defects in a unique manner. Overlapping but distinct roles of ERL1 and ERL2 can be ascribed largely to their intricate expression patterns rather than their functions as receptor kinases. Loss of the entire ERECTA family genes led to striking dwarfism, reduced lateral organ size and abnormal flower development, including defects in petal polar expansion, carpel elongation, and anther and ovule differentiation. These defects are due to severely reduced cell proliferation. Our findings place ERECTA-family RLKs as redundant receptors that link cell proliferation to organ growth and patterning. 相似文献
40.