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991.
Mohan Babu Roland Arnold Cedoljub Bundalovic-Torma Alla Gagarinova Keith S. Wong Ashwani Kumar Geordie Stewart Bahram Samanfar Hiroyuki Aoki Omar Wagih James Vlasblom Sadhna Phanse Krunal Lad Angela Yeou Hsiung Yu Christopher Graham Ke Jin Eric Brown Ashkan Golshani Philip Kim Gabriel Moreno-Hagelsieb Jack Greenblatt Walid A. Houry John Parkinson Andrew Emili 《PLoS genetics》2014,10(2)
Large-scale proteomic analyses in Escherichia coli have documented the composition and physical relationships of multiprotein complexes, but not their functional organization into biological pathways and processes. Conversely, genetic interaction (GI) screens can provide insights into the biological role(s) of individual gene and higher order associations. Combining the information from both approaches should elucidate how complexes and pathways intersect functionally at a systems level. However, such integrative analysis has been hindered due to the lack of relevant GI data. Here we present a systematic, unbiased, and quantitative synthetic genetic array screen in E. coli describing the genetic dependencies and functional cross-talk among over 600,000 digenic mutant combinations. Combining this epistasis information with putative functional modules derived from previous proteomic data and genomic context-based methods revealed unexpected associations, including new components required for the biogenesis of iron-sulphur and ribosome integrity, and the interplay between molecular chaperones and proteases. We find that functionally-linked genes co-conserved among γ-proteobacteria are far more likely to have correlated GI profiles than genes with divergent patterns of evolution. Overall, examining bacterial GIs in the context of protein complexes provides avenues for a deeper mechanistic understanding of core microbial systems. 相似文献
992.
M. Zouhair Atassi Midori Taruishi Masooma Naqvi Lance E. Steward K. Roger Aoki 《The protein journal》2014,33(3):278-288
Botulinum neurotoxin type B (BoNT/B) initiates its toxicity by binding to synaptotagmin II (SytII) and gangliosides GD1a and GT1b on the neural membrane. We synthesized two 27-residue peptides that carry the BoNT/B binding sites on mouse SytII (mSytII 37–63) or human SytII (hSytII 34–60). BoNT/B bound to these peptides, but showed substantially higher binding to mSytII peptide than to hSytII peptide. The mSytII peptide inhibited almost completely BoNT/B binding to synaptosomes (snps) and displayed a high affinity. BoNT/B bound strongly to mSytII peptide and binding was inhibited by the peptide. Binding of BoNT/B to snps was also inhibited (~80 %) by a larger excess of gangliosides GD1a or GT1b. The mSytII peptide inhibited very strongly (at least 80 %) the toxin binding to snps, while the two gangliosides were much less efficient inhibitors requiring much larger excess to achieve similar inhibition levels. Furthermore, gangliosides GD1a or GT1b inhibited BoNT/B binding to mSytII peptide at a much larger excess than the inhibition by mSytII peptide. Conversely, BoNT/B bound well to each ganglioside and binding could be inhibited by the correlate ganglioside and much less efficiently by the mSytII peptide. There was no apparent collaboration between mSytII peptide and either ganglioside. mSytII peptide displayed some protective activity in vivo in mice against a lethal BoNT/B dose. We concluded that SytII peptide and gangliosides bind independently but, with their binding sites on BoNT/B being spatially close, each can influence BoNT/B binding to the other due to regional conformational perturbations or steric interference or both. Ganglioside involvement in BoNT/B binding might help in toxin translocation and endocytosis. 相似文献
993.
Satoru Kurokawa Jun Kabayama Seong Don Hwang Seong Won Nho Jun-ichi Hikima Tae Sung Jung Hidehiro Kondo Ikuo Hirono Haruko Takeyama Tetsushi Mori Takashi Aoki 《Marine biotechnology (New York, N.Y.)》2014,16(5):572-579
Mycobacterium is a genus within the order Actinomycetales that comprises of a large number of well-characterized species, several of which includes pathogens known to cause serious disease in human and animal. Here, we report the whole genome sequence of Mycobacterium sp. strain 012931 isolated from the marine fish, yellowtail (Seriola quinqueradiata). Mycobacterium sp. 012931 is a fish pathogen causing serious damage to aquaculture farms in Japan. DNA dot plot analysis showed that Mycobacterium sp. 012931 was more closely related to Mycobacterium marinum when compared across several Mycobacterium species. However, little conservation of the gene order was observed between Mycobacterium sp. 012931 and M. marinum genome. The annotated 5,464 genes of Mycobacterium sp. 012931 was classified into 26 subsystems. The insertion/deletion gene analysis shows Mycobacterium sp. 012931 had 643 unique genes that were not found in the M. marinum strains. In the virulence, disease, and defense subsystem, both insertion and deletion genes of Mycobacterium sp. 012931 were associated with the PPE gene cluster of Mycobacteria. Of seven plcB genes in Mycobacterium sp. 012931, plcB_2 and plcB_3 showed low identities with those of M. marinum strains. Therefore, Mycobacterium sp. 012931 has differences on genetic and virulence from M. marinum and may induce different interaction mechanisms between host and pathogen. 相似文献
994.
Chieko Kurihara Hideo Kusuoka Shunsuke Ono Naoko Kakee Kazuyuki Saito Kenji Takehara Kiyokazu Tsujide Yuzo Nabeoka Takuya Sakuhiro Hiroshi Aoki Noriko Morishita Chieko Suzuki Shigeo Kachi Emiko Kondo Yukiko Komori Tetsu Isobe Shigeru Kageyama Hiroshi Watanabe 《PloS one》2014,9(1)
Introduction
International norms and ethical standards have suggested that compensation for research-related injury should be provided to injured research volunteers. However, statistical data of incidence of compensation claims and the rate of awarding them have been rarely reported.Method
Questionnaire surveys were sent to pharmaceutical companies and medical institutions, focusing on industry-initiated clinical trials aiming at new drug applications (NDAs) on patient volunteers in Japan.Results
With the answers from pharmaceutical companies, the incidence of compensation was 0.8%, including 0.06% of monetary compensation. Of the cases of compensation claims, 99% were awarded. In turn, with the answers from medical institutions, the incidence of compensation was 0.6%, including 0.4% of serious but not death cases, and 0.04% of death cases. Furthermore, most claims for compensation were initiated by medical institutions, rather than by the patients. On the other hand, with the answers from clinical trial volunteers, 3% of respondents received compensations. These compensated cases were 25% of the injuries which cannot be ruled out from the scope of compensation.Conclusion
Our study results demonstrated that Japanese pharmaceutical companies have provided a high rate of compensation for clinical trial-related injuries despite the possibility of overestimation. In the era of global clinical development, our study indicates the importance of further surveys to find each country''s compensation policy by determining how it is being implemented based on a survey of the actual status of compensation coming from statistical data. 相似文献995.
Previous investigations demonstrated that pyruvate protects human keratinocytes against cell damage stemming from exposure to ultraviolet B (UVB) radiation. This study endeavoured to elucidate the protective capacity of aromatic pyruvates (e.g., phenylpyruvate (PPyr), 4-hydroxyphenylpyruvate (HPPyr), and indole-3-pyruvate (IPyr)) against UVB-induced injury to skin cells, both in vitro and in vivo. Cultured human HaCaT keratinocytes were irradiated with UVB light (60 mJ/cm2) and maintained with or without test compounds (1–25 mM). In addition, the dorsal skin of hairless mice (HR-1) was treated with test compounds (100 µmol) and exposed to UVB light (1 J/cm2) for two times. The ability of the test compounds to ameliorate UVB-induced cytotoxicity and inflammation was then assessed. Aromatic pyruvates reduced cytotoxicity in UVB-irradiated HaCaT keratinocytes, and also diminished the expression of interleukin 1β (IL-1β) and interleukin 6 (IL-6). IPyr was more efficacious than either PPyr or HPPyr. Furthermore, only IPyr inhibited cyclooxygenase-2 (Cox-2) expression at both the mRNA and the protein level in UVB-treated keratinocytes. Topical application of IPyr to the dorsal skin of hairless mice reduced the severity of UVB-induced skin lesions, the augmentation of dermal thickness, and transepithelial water loss. Overproduction of IL-1β and IL-6 in response to UVB radiation was also suppressed in vivo by the topical administration of IPyr. These data strongly suggest that IPyr might find utility as a UVB-blocking reagent in therapeutic strategies to lessen UVB-induced inflammatory skin damage. 相似文献
996.
997.
Tomoya Hirose Shigeto Hamaguchi Naoya Matsumoto Taro Irisawa Masafumi Seki Osamu Tasaki Hideo Hosotsubo Norihisa Yamamoto Kouji Yamamoto Yukihiro Akeda Kazunori Oishi Kazunori Tomono Takeshi Shimazu 《PloS one》2014,9(11)
Neutrophil extracellular traps (NETs), a newly identified immune mechanism, are induced by inflammatory stimuli. Modification by citrullination of histone H3 is thought to be involved in the in vitro formation of NETs. The purposes of this study were to evaluate whether NETs and citrullinated histone H3 (Cit-H3) are present in the bloodstream of critically ill patients and to identify correlations with clinical and biological parameters. Blood samples were collected from intubated patients at the time of ICU admission from April to June 2011. To identify NETs, DNA and histone H3 were visualized simultaneously by immunofluorescence in blood smears. Cit-H3 was detected using a specific antibody. We assessed relationships of the presence of NETs and Cit-H3 with the existence of bacteria in tracheal aspirate, SIRS, diagnosis, WBC count, and concentrations of IL-8, TNF-α, cf-DNA, lactate, and HMGB1. Forty-nine patients were included. The median of age was 66.0 (IQR: 52.5–76.0) years. The diagnoses included trauma (7, 14.3%), infection (14, 28.6%), resuscitation from cardiopulmonary arrest (8, 16.3%), acute poisoning (4, 8.1%), heart disease (4, 8.1%), brain stroke (8, 16.3%), heat stroke (2, 4.1%), and others (2, 4.1%). We identified NETs in 5 patients and Cit-H3 in 11 patients. NETs and/or Cit-H3 were observed more frequently in “the presence of bacteria in tracheal aspirate” group (11/22, 50.0%) than in “the absence of bacteria in tracheal aspirate” group (4/27, 14.8%) (p<.01). Multiple logistic regression analysis showed that only the presence of bacteria in tracheal aspirate was significantly associated with the presence of NETs and/or Cit-H3. The presence of bacteria in tracheal aspirate may be one important factor associated with NET formation. NETs may play a pivotal role in the biological defense against the dissemination of pathogens from the respiratory tract to the bloodstream in potentially infected patients. 相似文献
998.
Tetsuya Akaishi Takuhiro Yamaguchi Yasushi Suzuki Yuriko Nagane Shigeaki Suzuki Hiroyuki Murai Tomihiro Imai Masakatsu Motomura Kazuo Fujihara Masashi Aoki Kimiaki Utsugisawa 《PloS one》2014,9(9)
Background and Purpose
Myasthenia gravis (MG) is often categorized into thymoma-associated MG, early-onset MG with onset age <50 years, and late-onset MG with onset age ≥50 years. However, the boundary age of 50 years old between early- and late-onset MG remains controversial, and each category contains further subtypes. We attempted to classify MG from a statistical perspective.Methods
We analyzed 640 consecutive MG patients using two-step cluster analysis with clinical variables and discrimination analysis, using onset age as a variable.Results
Two-step cluster analyses categorized MG patients into the following five subtypes: ocular MG; MG with thymic hyperplasia (THMG); generalized anti-acetylcholine receptor antibody (AChR-Ab)-negative MG; thymoma-associated MG; and generalized AChR-Ab-positive (SP) MG without thymic abnormalities. Among these 5 subtypes, THMG showed a distribution of onset age skewed toward a younger age (p<0.01), whereas ocular MG and SPMG without thymic abnormalities showed onset age skewed toward an older age (p<0.001 and p<0.0001, respectively). The other 2 subtypes showed normal distributions. THMG appeared as the main component of early-onset MG, and ocular MG and SPMG without thymic abnormalities as the main components of late-onset MG. Discrimination analyses between THMG and ocular MG and/or SPMG without thymic abnormalities demonstrated a boundary age of 45 years old.Conclusions
From a statistical perspective, the boundary age between early- and late-onset MG is about 45 years old. 相似文献999.
Masataka Aoki Masayuki Ehara Yumi Saito Hideyoshi Yoshioka Masayuki Miyazaki Yayoi Saito Ai Miyashita Shuji Kawakami Takashi Yamaguchi Akiyoshi Ohashi Takuro Nunoura Ken Takai Hiroyuki Imachi 《PloS one》2014,9(8)
Anaerobic oxidation of methane (AOM) in marine sediments is an important global methane sink, but the physiological characteristics of AOM-associated microorganisms remain poorly understood. Here we report the cultivation of an AOM microbial community from deep-sea methane-seep sediment using a continuous-flow bioreactor with polyurethane sponges, called the down-flow hanging sponge (DHS) bioreactor. We anaerobically incubated deep-sea methane-seep sediment collected from the Nankai Trough, Japan, for 2,013 days in the bioreactor at 10°C. Following incubation, an active AOM activity was confirmed by a tracer experiment using 13C-labeled methane. Phylogenetic analyses demonstrated that phylogenetically diverse Archaea and Bacteria grew in the bioreactor. After 2,013 days of incubation, the predominant archaeal components were anaerobic methanotroph (ANME)-2a, Deep-Sea Archaeal Group, and Marine Benthic Group-D, and Gammaproteobacteria was the dominant bacterial lineage. Fluorescence in situ hybridization analysis showed that ANME-1 and -2a, and most ANME-2c cells occurred without close physical interaction with potential bacterial partners. Our data demonstrate that the DHS bioreactor system is a useful system for cultivating fastidious methane-seep-associated sedimentary microorganisms. 相似文献
1000.
Yoshikuni Kawaguchi Yasuhiko Sugawara Nobuhisa Akamatsu Junichi Kaneko Tsuyoshi Hamada Tomohiro Tanaka Takeaki Ishizawa Sumihito Tamura Taku Aoki Yoshihiro Sakamoto Kiyoshi Hasegawa Norihiro Kokudo 《PloS one》2014,9(11)