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排序方式: 共有380条查询结果,搜索用时 15 毫秒
61.
Haruna Ishikawa Xiaoxu Guo Saeko Sugawara Yui Iwagaki Kazushi Yamamoto 《Bioscience, biotechnology, and biochemistry》2018,82(3):515-524
We examined the effects on offspring of ingestion of the 1975 Japanese diet during pregnancy and lactation and after weaning in mice. Pregnant dams were divided into groups that were fed the Japanese diet or a control diet and raised until offspring were weaned. The offspring after weaning were further divided into groups that were raised on the Japanese diet or the control diet. Ingestion of the Japanese diet after weaning suppressed accumulation of visceral fat in offspring, and reduced the amount of lipids in serum and liver. This effect was weakened if the Japanese diet was only ingested during pregnancy and lactation. Therefore, it was suggested that ingestion of the Japanese diet of mothers during pregnancy and lactation weakens the lipid accumulation inhibitory effect of the Japanese diet in children. 相似文献
62.
63.
Role of the Cytoplasmic Membrane in the Synthesis of Ribonucleic Acid by Disrupted Spheroplasts of Pseudomonas schuylkilliensis 总被引:2,自引:2,他引:0 下载免费PDF全文
Disrupted spheroplast preparations of Pseudomonas schuylkilliensis strain P contained fragments of cytoplasmic membrane and approximately 82% of the total cellular phospholipid. The protoplast-bursting factor (PB-factor), partially purified from pig pancreas, and a heat-treated pancreatic lipase fraction both inhibited ribonucleic acid (RNA) synthesis by disrupted spheroplasts but did not inhibit or only slightly inhibited RNA synthesis by intact cells or intact spheroplasts. The PB-factor preparation and the heat-treated pancreatic lipase fraction catalyzed partial (15 to 50%) deacylation of diphosphatidylglycerol, phosphatidylglycerol, and phosphatidylethanolamine in disrupted spheroplasts but not in intact spheroplasts. Phospholipase A activity was demonstrated in the PB-factor preparation by use of isolated phospholipids as substrates. Treatment of disrupted spheroplasts with the PB-factor preparation caused a 70% inhibition in oxidative phosphorylation and RNA synthesis, but had little effect on electron transport. Addition of adenosine-5'-triphosphate or adenosine-5'-diphosphate and a mixture of ribonucleosides after treatment with the PB-factor preparation partially restored oxidative phosphorylation but did not relieve the inhibition in RNA synthesis. The most reasonable explanation for the latter observation appears to be that the concentrations of newly synthesized nucleotides retained by the preparations with partially deacylated membrane phospholipids were insufficient to permit the synthesis of RNA. 相似文献
64.
Tunicamycin-resistant mutants and chromosomal locations of mutational sites in Bacillus subtilis. 下载免费PDF全文
The types of tunicamycin-resistant mutants of Bacillus subtilis were analyzed, and their mutational sites on the chromosome were mapped. A type 1 mutation that simultaneously expressed hyperproductivity of extracellular alpha-amylase was located close to amy E. Type 2 mutations were near aroI. 相似文献
65.
Ohara Chisato Sekiguchi Atsushi Takakura Shu Endo Yuka Tamura Naho Kikuchi Hiroe Maruo Kazushi Sugawara Norio Hatano Kenji Kawanishi Hitomi Funaba Misako Sugawara Ayako Nohara Nobuhiro Kawai Keisuke Fukudo Shin Sudo Nobuyuki Cooper Zafra Yoshiuchi Kazuhiro Ando Tetsuya 《BioPsychoSocial medicine》2020,14(1):1-3
Although fatigue is a common and distressing symptom in cancer survivors, the mechanism of fatigue is not fully understood. Therefore, this study aims to investigate the relation between the fatigue and mindfulness of breast cancer survivors using anxiety, depression, pain, loneliness, and sleep disturbance as mediators. Path analysis was performed to examine direct and indirect associations between mindfulness and fatigue. Participants were breast cancer survivors who visited a breast surgery department at a university hospital in Japan for hormonal therapy or regular check-ups after treatment. The questionnaire measured cancer-related-fatigue, mindfulness, anxiety, depression, pain, loneliness, and sleep disturbance. Demographic and clinical characteristics were collected from medical records. Two-hundred and seventy-nine breast cancer survivors were registered, of which 259 answered the questionnaire. Ten respondents with incomplete questionnaire data were excluded, resulting in 249 participants for the analyses. Our final model fit the data well (goodness of fit index = .993; adjusted goodness of fit index = .966; comparative fit index = .999; root mean square error of approximation = .016). Mindfulness, anxiety, depression, pain, loneliness, and sleep disturbance were related to fatigue, and mindfulness had the most influence on fatigue (β = − .52). Mindfulness affected fatigue not only directly but also indirectly through anxiety, depression, pain, loneliness, and sleep disturbance. The study model helps to explain the process by which mindfulness affects fatigue. Our results suggest that mindfulness has both direct and indirect effects on the fatigue of breast cancer survivors and that mindfulness can be used to more effectively reduce their fatigue. It also suggests that health care professionals should be aware of factors such as anxiety, depression, pain, loneliness, and sleep disturbance in their care for fatigue of breast cancer survivors. This study was registered in the University Hospital Medical Information Network Clinical Trials Registry (UMIN number. 000027720) on June 12, 2017. 相似文献
66.
Shigero Tamba Rieko Yodoi Kazushi Morimoto Tomoaki Inazumi Mamiko Sukeno Eri Segi-Nishida Yasushi Okuno Gozoh Tsujimoto Shuh Narumiya Yukihiko Sugimoto 《Biochimie》2010
To understand the role of prostaglandin (PG) receptor EP2 (Ptger2) signaling in ovulation and fertilization, we investigated time-dependent expression profiles in wild-type (WT) and Ptger2−/− cumuli before and after ovulation by using microarrays. We prepared cumulus cells from mice just before and 3, 9 and 14 h after human chorionic gonadotropin injection. Key genes including cAMP-related and epidermal growth factor (EGF) genes, as well as extracellular matrix- (ECM-) related and chemokine genes were up-regulated in WT cumuli at 3 h and 14 h, respectively. Ptger2 deficiency differently affected the expression of many of the key genes at 3 h and 14 h. These results indicate that the gene expression profile of cumulus cells greatly differs before and after ovulation, and in each situation, PGE2-EP2 signaling plays a critical role in cAMP-regulated gene expression in the cumulus cells under physiological conditions. 相似文献
67.
Naoyuki Miyata Kanako Maruo Yukinori Tani Hiroshi Tsuno Haruhiko Seyama Mitsuyuki Soma 《Geomicrobiology journal》2013,30(2):63-73
We characterized the production of biogenic Mn oxides by four anamorphic ascomycete fungi isolated from streambed pebbles with Mn oxide coatings. Based on the 18S rRNA gene sequences, one strain was related to members of the order Xylariales and the other three were within distinct lineages of the Pleosporales. These strains oxidized Mn(II) to deposit Mn oxides when their growth approached the stationary phase. The fungal Mn oxides showed X-ray diffraction patterns typical of poorly crystalline vernadite (δ -MnO2), and X-ray absorption near-edge structure spectroscopy confirmed that the Mn phases consisted predominantly of Mn(IV). Mn(II) oxidation in the four strains proceeded enzymatically. The Mn(II)-oxidizing proteins were inhibited by azide and o-phenanthroline, and the proteins also oxidized typical laccase substrates including 2,2′-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), showing the role of laccase or a laccase-like metalloenzyme. The mineralogical traits of the biogenic Mn oxides, and the participation of laccase-like enzymes, are in accordance with our previous results obtained with one Hypocreales ascomycete. In conclusion, phylogenetically diverse ascomycetes may use this common enzymatic system to produce solid Mn phases similar to δ -MnO2. 相似文献
68.
69.
Satoshi Yamamoto Kenji Minami Keiichi Fukaya Kohji Takahashi Hideki Sawada Hiroaki Murakami Satsuki Tsuji Hiroki Hashizume Shou Kubonaga Tomoya Horiuchi Masamichi Hongo Jo Nishida Yuta Okugawa Ayaka Fujiwara Miho Fukuda Shunsuke Hidaka Keita W. Suzuki Masaki Miya Hitoshi Araki Hiroki Yamanaka Atsushi Maruyama Kazushi Miyashita Reiji Masuda Toshifumi Minamoto Michio Kondoh 《PloS one》2016,11(3)
Recent studies in streams and ponds have demonstrated that the distribution and biomass of aquatic organisms can be estimated by detection and quantification of environmental DNA (eDNA). In more open systems such as seas, it is not evident whether eDNA can represent the distribution and biomass of aquatic organisms because various environmental factors (e.g., water flow) are expected to affect eDNA distribution and concentration. To test the relationships between the distribution of fish and eDNA, we conducted a grid survey in Maizuru Bay, Sea of Japan, and sampled surface and bottom waters while monitoring biomass of the Japanese jack mackerel (Trachurus japonicus) using echo sounder technology. A linear model showed a high R2 value (0.665) without outlier data points, and the association between estimated eDNA concentrations from the surface water samples and echo intensity was significantly positive, suggesting that the estimated spatial variation in eDNA concentration can reflect the local biomass of the jack mackerel. We also found that a best-fit model included echo intensity obtained within 10–150 m from water sampling sites, indicating that the estimated eDNA concentration most likely reflects fish biomass within 150 m in the bay. Although eDNA from a wholesale fish market partially affected eDNA concentration, we conclude that eDNA generally provides a ‘snapshot’ of fish distribution and biomass in a large area. Further studies in which dynamics of eDNA under field conditions (e.g., patterns of release, degradation, and diffusion of eDNA) are taken into account will provide a better estimate of fish distribution and biomass based on eDNA. 相似文献
70.
Kazushi Motomura Masaru Yokoyama Hirotaka Ode Hiromi Nakamura Hiromi Mori Tadahito Kanda Tomoichiro Oka Kazuhiko Katayama Mamoru Noda Tomoyuki Tanaka Naokazu Takeda Hironori Sato the Norovirus Surveillance Group of Japan ? 《Journal of virology》2010,84(16):8085-8097
Norovirus GII/4 is a leading cause of acute viral gastroenteritis in humans. We examined here how the GII/4 virus evolves to generate and sustain new epidemics in humans, using 199 near-full-length GII/4 genome sequences and 11 genome segment clones from human stool specimens collected at 19 sites in Japan between May 2006 and February 2009. Phylogenetic studies demonstrated outbreaks of 7 monophyletic GII/4 subtypes, among which a single subtype, termed 2006b, had continually predominated. Phylogenetic-tree, bootscanning-plot, and informative-site analyses revealed that 4 of the 7 GII/4 subtypes were mosaics of recently prevalent GII/4 subtypes and 1 was made up of the GII/4 and GII/12 genotypes. Notably, single putative recombination breakpoints with the highest statistical significance were constantly located around the border of open reading frame 1 (ORF1) and ORF2 (P ≤ 0.000001), suggesting outgrowth of specific recombinant viruses in the outbreaks. The GII/4 subtypes had many unique amino acids at the time of their outbreaks, especially in the N-term, 3A-like, and capsid proteins. Unique amino acids in the capsids were preferentially positioned on the outer surface loops of the protruding P2 domain and more abundant in the dominant subtypes. These findings suggest that intersubtype genome recombination at the ORF1/2 boundary region is a common mechanism that realizes independent and concurrent changes on the virion surface and in viral replication proteins for the persistence of norovirus GII/4 in human populations.Norovirus (NoV) is a nonenveloped RNA virus that belongs to the family Caliciviridae and can cause acute gastroenteritis in humans. The NoV genome is a single-stranded, positive-sense, polyadenylated RNA that encodes three open reading frames, ORF1, ORF2, and ORF3 (68). ORF1 encodes a long polypeptide (∼200 kDa) that is cleaved in the cells by the viral proteinase (3Cpro) into six proteins (4). These proteins function in NoV replication in host cells (19). ORF2 encodes a viral capsid protein, VP1. The capsid gene evolved at a rate of 4.3 × 10−3 nucleotide substitutions/site/year (7), which is comparable to the substitution rates of the envelope and capsid genes of human immunodeficiency virus (30). The capsid protein of NoV consists of a shell (S) and two protruding (P) domains: P1 and P2 (47). The S domain is relatively conserved within the same genetic lineages of NoVs (38) and is responsible for the assembly of VP1 (6). The P1 subdomain is also relatively conserved (38) and has a role in enhancing the stability of virus particles (6). The P2 domain is positioned at the most exposed surface of the virus particle (47) and forms binding clefts for putative infection receptors, such as human histo-blood group antigens (HBGA) (8, 13, 14, 60). The P2 domain also contains epitopes for neutralizing antibodies (27, 33) and is consistently highly variable even within the same genetic lineage of NoVs (38). ORF3 encodes a VP2 protein that is suggested to be a minor structural component of virus particles (18) and to be responsible for the expression and stabilization of VP1 (5).Thus far, the NoVs found in nature are classified into five genogroups (GI to GV) and multiple genotypes on the basis of the phylogeny of capsid sequences (71). Among them, genogroup II genotype 4 (GII/4), which was present in humans in the mid-1970s (7), is now the leading cause of NoV-associated acute gastroenteritis in humans (54). The GII/4 is further subclassifiable into phylogenetically distinct subtypes (32, 38, 53). Notably, the emergence and spread of a new GII/4 subtype with multiple amino acid substitutions on the capsid surface are often associated with greater magnitudes of NoV epidemics (53, 54). In 2006 and 2007, a GII/4 subtype, termed 2006b, prevailed globally over preexisting GII/4 subtypes in association with increased numbers of nonbacterial acute gastroenteritis cases in many countries, including Japan (32, 38, 53). The 2006b subtype has multiple unique amino acid substitutions that occur most preferentially in the protruding subdomain of the capsid, the P2 subdomain (32, 38, 53). Together with information on human population immunity against NoV GII/4 subtypes (12, 32), it has been postulated that the accumulation of P2 mutations gives rise to antigenic drift and plays a key role in new epidemics of NoV GII/4 in humans (32, 38, 53).Genetic recombination is common in RNA viruses (67). In NoV, recombination was first suggested by the phylogenetic analysis of an NoV genome segment clone: a discordant branching order was noted with the trees of the 3Dpol and capsid coding regions (21). Subsequently, many studies have reported the phylogenetic discordance using sequences from various epidemic sites in different study periods (1, 10, 11, 16, 17, 22, 25, 40, 41, 44-46, 49, 51, 57, 63, 64, 66). These results suggest that genome recombination frequently occurs among distinct lineages of NoV variants in vivo. However, the studies were done primarily with direct sequencing data of the short genome portion, and information on the cloned genome segment or full-length genome sequences is very limited (21, 25). Therefore, we lack an overview of the structural and temporal dynamics of viral genomes during NoV epidemics, and it remains unclear whether NoV mosaicism plays a role in these events.To clarify these issues, we collected 199 near-full-length genome sequences of GII/4 from NoV outbreaks over three recent years in Japan, divided them into monophyletic subtypes, analyzed the temporal and geographical distribution of the subtypes, collected phylogenetic evidence for the viral genome mosaicism of the subtypes, identified putative recombination breakpoints in the genomes, and isolated mosaic genome segments from the stool specimens. We also performed computer-assisted sequence and structural analyses with the identified subtypes to address the relationship between the numbers of P2 domain mutations at the times of the outbreaks and the magnitudes of the epidemics. The obtained data suggest that intersubtype genome recombination at the ORF1/2 boundary region is common in the new GII/4 outbreaks and promotes the effective acquisition of mutation sets of heterogeneous capsid surface and viral replication proteins. 相似文献