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101.
Hebeloma vinosophyllum (Basidiomycota, Agaricales), a member of the ammonia fungi, occurred on the ground in the close vicinity of the decomposed
carcass of a jungle crow,Corvus macrorhynchos, in a forest dominated byQuercus spp. in Urawa, Saitama Pref., central Japan. This is the first report of an ammonia fungus occurring at the site of a decomposed
wild bird carcass. 相似文献
102.
Yoshimura K Miyamoto Y Yasuhara R Maruyama T Akiyama T Yamada A Takami M Suzawa T Tsunawaki S Tachikawa T Baba K Kamijo R 《The Journal of biological chemistry》2011,286(17):14744-14752
Interleukin-1β (IL-1β) induces cell death in chondrocytes in a nitric oxide (NO)- and reactive oxygen species (ROS)-dependent manner. In this study, increased production of lactate was observed in IL-1β-treated mouse chondrocytic ATDC5 cells prior to the onset of their death. IL-1β-induced cell death in ATDC5 cells was suppressed by introducing an siRNA for monocarboxylate transporter-1 (MCT-1), a lactate transporter distributed in plasma and mitochondrial inner membranes. Mct-1 knockdown also prevented IL-1β-induced expression of phagocyte-type NADPH oxidase (NOX-2), an enzyme specialized for production of ROS, whereas it did not have an effect on inducible NO synthase. Suppression of IL-1β-induced cell death by Nox-2 siRNA indicated that NOX-2 is involved in cell death. Phosphorylation and degradation of inhibitor of κBα (IκBα) from 5 to 20 min after the addition of IL-1β was not affected by Mct-1 siRNA. In addition, IκBα was slightly decreased after 12 h of incubation with IL-1β, and the decrease was prominent after 36 h, whereas activation of p65/RelA was observed from 12 to 48 h after exposure to IL-1β. These changes were not seen in Mct-1-silenced cells. Forced expression of IκBα super repressor as well as treatment with the IκB kinase inhibitor BAY 11-7082 suppressed NOX-2 expression. Furthermore, Mct-1 siRNA lowered the level of ROS generated after 15-h exposure to IL-1β, whereas a ROS scavenger, N-acetylcysteine, suppressed both late phase degradation of IκBα and Nox-2 expression. These results suggest that MCT-1 contributes to NOX-2 expression via late phase activation of NF-κB in a ROS-dependent manner in ATDC5 cells exposed to IL-1β. 相似文献
103.
104.
Harada H Shindo K Iki K Teraoka A Okamoto S Yu F Hattan J Utsumi R Misawa N 《Applied microbiology and biotechnology》2011,90(2):467-476
Tractable plasmids (pAC-Mv-based plasmids) for Escherichia coli were constructed, which carried a mevalonate-utilizing gene cluster, towards an efficient functional analysis of cytochromes
P450 involved in sesquiterpene biosynthesis. They included genes coding for a series of redox partners that transfer the electrons
from NAD(P)H to a P450 protein. The redox partners used were ferredoxin reductases (CamA and NsRED) and ferredoxins (CamB
and NsFER), which are derived from Pseudomonas putida and cyanobacterium Nostoc sp. strain PCC 7120, respectively, as well as three higher-plant NADPH-P450 reductases, the Arabidopsis thaliana ATR2 and two corresponding enzymes derived from ginger (Zingiber officinale), named ZoRED1 and ZoRED2. We also constructed plasmids for functional analysis of two P450s, α-humulene-8-hydroxylase (CYP71BA1)
from shampoo ginger (Zingiber zerumbet) and germacrene A hydroxylase (P450NS; CYP110C1) from Nostoc sp. PCC 7120, and co-transformed E. coli with each of the pAC-Mv-based plasmids. Production levels of 8-hydroxy-α-humulene with recombinant E. coli cells (for CYP71BA1) were 1.5- to 2.3-fold higher than that of a control strain without the mevalonate-pathway genes. Level
of the P450NS product with the combination of NsRED and NsFER was 2.9-fold higher than that of the CamA and CamB. The predominant
product of P450NS was identified as 1,2,3,5,6,7,8,8a-octahydro-6-isopropenyl-4,8a-dimethylnaphth-1-ol with NMR analyses. 相似文献
105.
106.
The burrows created by benthos in tidal flats provide various habitats to other organisms. Echiuran burrows are unique among these in being persistently disturbed by the host's undulating activity, but little is known on how symbionts adapt to such a unique habitat. We report here the morphological and ecological adaptation by two bivalve species of Basterotia (Sportellidae), including one new species, which are commensals with burrowing echiuran worms. The burrows of Ikedosoma gogoshimense were inhabited by Basterotia gouldi at intertidal gravelly mud flats in the central Seto Inland Sea, whereas those of Ochetostoma erythrogrammon were inhabited by Basterotia carinata n. sp. at an intertidal gravelly coral-sand flat at Amami-Ohshima Island. Both bivalve species were found embedded in the burrow wall with their posterior inhalant and exhalant apertures gaping to the burrow lumen, suggesting that they utilize the water currents created by host echiurans. The posteriorly robust, laterally inflated shell with developed carina is considered an adaptation to symbiotic life, as it is exposed to pressure caused by the host's persistent undulating activity. Females of Basterotia bivalves were larger than males, suggesting size-dependent sex change, and possessed brooded veligers in the ctenidium. Our findings suggest that species-specific intimate association with echiurans may be widespread among the Sportellidae bivalves, whose biology remains poorly understood. 相似文献
107.
Chika Sato Masato Hoshino Naori Ikumi Kentarou Oba Akiko Koike Osamu Shouno Tatsuhiko Sekiguchi Tetsuya Kobayashi Takeo Machida Gen Matsumoto Hiroyuki Furudate Tetsuya Kimura 《PloS one》2014,9(4)
In recent years, the study of resting state neural activity has received much attention. To better understand the roles of different brain regions in the regulation of behavioral activity in an arousing or a resting period, we developed a novel behavioral paradigm (8-arm food-foraging task; 8-arm FFT) using the radial 8-arm maze and examined how AcbC lesions affect behavioral execution and learning. Repetitive training on the 8-arm FFT facilitated motivation of normal rats to run quickly to the arm tips and to the center platform before the last-reward collection. Importantly, just after this point and before confirmation of no reward at the next arm traverse, locomotor activity decreased. This indicates that well-trained rats can predict the absence of the reward at the end of food seeking and then start another behavior, namely planned resting. Lesions of the AcbC after training selectively impaired this reduction of locomotor activity after the last-reward collection without changing activity levels before the last-reward collection. Analysis of arm-selection patterns in the lesioned animals suggests little influence of the lesion in the ability to predict the reward absence. AcbC lesions did not change exploratory locomotor activity in an open-field test in which there were no rewards. This suggests that the AcbC controls the activity level of planned resting behavior shaped by the 8-arm FFT. Rats receiving training after AcbC lesioning showed a reduction in motivation for reward seeking. Thus, the AcbC also plays important roles not only in controlling the activity level after the last-reward collection but also in motivational learning for setting the activity level of reward-seeking behavior. 相似文献
108.
Hideyuki Sawada Tomoko Oeda Atsushi Umemura Satoshi Tomita Ryutaro Hayashi Masayuki Kohsaka Kenji Yamamoto Shinji Sudoh Hiroshi Sugiyama 《PloS one》2014,9(1)
Background
Though infections are associated with psychotic symptoms, whether or not subclinical inflammation is associated with hallucinations is not known in Parkinson’s disease (PD).Purpose
To investigate the association of illusions/hallucinations and plasma CRP levels in PD patients without symptomatic infections.Methods
PD patients not diagnosed as having infections were assessed for illusions and hallucinations using the Parkinson Psychosis Questionnaire (PPQ). It comprises four-domain questions: PPQ-A for sleep problems, PPQ-B for hallucinations/illusions, PPQ-C for delusions, and PPQ-D for disorientation. Assigning patients with ≥1 points in the PPQ-B score to be cases and others as controls, the association of hallucinations/illusions and clinical features (age, sex, duration of PD, Unified Parkinson’s Disease Rating Scale part 3 (UPDRS-3), Mini-Mental State Examination (MMSE) score, sleep disturbance (PPQ-A score) as well as daily doses of L-Dopa, dopamine agonists, amantadine, and selegiline) were analyzed using a case–control design.Results
A total of 111 patients were examined and plasma CRP levels were <0.1–6.0 mg/L. Hallucinations or illusions were detected in 28 (25.2%). There were significant differences in age, UPDRS-3 score, MMSE score, PPQ-A, daily doses of L-Dopa and dopamine agonists and plasma CRP levels between cases and controls. A multivariate logistic regression model revealed that UPDRS-3 scores and plasma CRP levels were significantly associated with hallucinations/illusions with an adjusted odds ratio of 1.96 (95% confidence interval (CI) 1.20–3.20) per 10 points and 1.57 (95% confidence interval 1.13–2.16) per two-fold, respectively. Dividing patients into thirds by CRP levels (≤0.2, 0.3–0.6, ≥0.7 mg/L), the prevalence of hallucinations/illusions was 13.2%, 21.6%, and 41.7%, in the bottom-, middle-, and top-thirds, respectively (for trend p = 0.012).Conclusions
Subclinical elevation of plasma CRP levels was associated with hallucinations or illusions after adjustment for motor disability, suggesting that subclinical elevations of CRP levels might be an independent risk for hallucinations/illusions. 相似文献109.
110.
Yuichiro Amano Eiichiro IshikawaEmiko Shinozawa Mitsuyuki ShimadaShotaro Miura Ryutaro AdachiRyuichi Tozawa 《Life sciences》2014