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791.
The pathogenic roles of nitric oxide (NO) in mouse models have been reported for herpes simplex virus type 1 (HSV-1)-induced pneumonia as well as endotoxin shock. We compared the mechanism of NO production induced by HSV-1 with that induced by lipopolysaccharide (LPS) using a mouse macrophage cell line, J774A.1. Both HSV-1 and LPS induced NO production as well as antiviral activity, which were attenuated by anti-interferon (IFN)-beta treatment. These results suggest that autocrine IFN-beta plays a role in NO release by J774A.1 cells stimulated with HSV-1 or LPS.  相似文献   
792.
A new nematicidal alkaloid, peniprequinolone (1), together with the known alkaloids penigequinolones A and B (2a, 2b), 3-methoxy-4-hydroxy-4-(4'-methoxyphenyl)quinolinone (3), and 3-methoxy-4,6-dihydroxy-4-(4'-methoxyphenyl)quinolinone (4), were isolated from Penicillium cf. simplicissimum (Oudemans) Thom. Cyclopenin (5) and a compound (6a/6b) structurally related to cyclopenin also were isolated from the fungus, and their structures were established by spectroscopic analysis. The biological activities of 1, 2, 3, 4, and 5 were examined by a bioassay with root-lesion nematodes.  相似文献   
793.
Changes in the phytoalexin content in unripe fruit of banana, Musa acuminata, were analyzed after various treatments. The results show that level of hydroxyanigorufone started to increase 1-2 day after either wounding or inoculation with conidia of Colletotrichum musae. Inoculation followed by wounding induced the formation of many other phenylphenalenones. The accumulation of hydroxyanigorufone decreased, after its transient maximum, on ripening by exposure of the wounded fruit to ethylene. The level of production of hydroxyanigorufone in ripe fruit treated by wounding and/or by inoculation was much lower than that in unripe fruit. 2-Aminooxyacetic acid, an inhibitor of phenylalanine ammonia-lyase (PAL), inhibited the accumulation of hydroxyanigorufone in wounded fruit, and the PAL activity increased after wounding and ethylene treatment, respectively. Feeding experiments with [1-(13)C] and [2-(13)C]cinnamic acids, and [2-(13)C]malonate show that two molecules of cinnamic acid and one of malonate were incorporated into each molecule of hydroxyanigorufone. The phytoalexins isolated from fruit to which deuterated hydroxyanigorufone and irenolone had been administered revealed that 2-(4'-hydroxyphenyl)-1,8-naphthalic anhydride was biosynthesized from hydroxyanigorufone rather than from irenolone.  相似文献   
794.
Quarrying is an important industry that supports human infrastructure, but it has negative effects on human health, environments, and plant communities. In the case of the serpentine quarry on Sugashima Island (Sugashima), Japan, rapid remediation using native plants is necessary to restore the serpentine ecosystem. According to our previous work, we revealed high adaptability of Japanese wild thyme (Thymus quinquecostatus Celak.) to the severe environment of serpentine areas, and we desired to utilize this species for revegetation. However, basic information on Japanese thyme was extremely limited, in comparison with well-investigated European thymes that have been used for revegetation experiments. The aims of this work were to identify the plant functional traits of wild thymes collected from different areas of Japan and to test their potential for revegetation of serpentine quarry soil. We collected four types of wild thyme from Sugashima and other areas of serpentine, calcareous, and tuff breccia soil, and revealed varietal differences in leaf form, branching patterns, flowers, and also blooming season, seed formation ability, and seed germination percentages. Thymes from serpentine and calcareous areas could grow on soil of the serpentine quarry, and a small number of plants were able to cover the experimental plots. Among the Japanese thymes investigated, Sugashima thyme had the longest branches, and spread rapidly by forming many branches. These data suggest that Japanese thymes, especially Sugashima thyme, have good potential for revegetation of serpentine quarries.  相似文献   
795.
Biological networks have two modes. The first mode is static: a network is a passage on which something flows. The second mode is dynamic: a network is a pattern constructed by gluing functions of entities constituting the network. In this paper, first we discuss that these two modes can be associated with the category theoretic duality (adjunction) and derive a natural network structure (a path notion) for each mode by appealing to the category theoretic universality. The path notion corresponding to the static mode is just the usual directed path. The path notion for the dynamic mode is called lateral path which is the alternating path considered on the set of arcs. Their general functionalities in a network are transport and coherence, respectively. Second, we introduce a betweenness centrality of arcs for each mode and see how the two modes are embedded in various real biological network data. We find that there is a trade-off relationship between the two centralities: if the value of one is large then the value of the other is small. This can be seen as a kind of division of labor in a network into transport on the network and coherence of the network. Finally, we propose an optimization model of networks based on a quality function involving intensities of the two modes in order to see how networks with the above trade-off relationship can emerge through evolution. We show that the trade-off relationship can be observed in the evolved networks only when the dynamic mode is dominant in the quality function by numerical simulations. We also show that the evolved networks have features qualitatively similar to real biological networks by standard complex network analysis.  相似文献   
796.
The biomass and population dynamics of crustacean zooplankton were determined in oligotrophic Lake Toya in Japan over 5 years from May 1992 to May 1997. In 1992 and 1993, zooplankton biomass was up to 4.3 g dry weight m?2, whereas it decreased to <1 g dry weight m?2 after 1994. This extreme change in biomass was associated with the succession of dominant species from larger ones, such as Daphnia longispina and Cyclops strenuus (s. lat.), to smaller ones, such as Eubosmina tanakai and Bosmina longirostris. Consequently, this biomass change seemed to cause an increase in the chlorophyll a concentration in the euphotic zone and a decline in lake transparency. Because the birth rates of the dominant species were somewhat higher after 1994, the decline in the populations of larger crustaceans seemed to depend more on their rate of death rather than rate of birth, and this higher death rate is not considered to be attributed to food shortage. Although these results strongly suggest a top-down cascading effect of fish predation upon crustaceans, annual catches of two commercially important planktivorous fish species have also decreased in the lake, coincidentally with decreases in zooplankton biomass. This may be attributable to fishing regulations that prohibit catching smaller fish, implying that such smaller fish affect zooplankton and phytoplankton, as well as lake transparency.  相似文献   
797.

Purpose

The UK carbonated drinks sector was worth £8 billion in 2010 and is growing at an annual rate of 4.9 %. In an attempt to provide a better understanding of the environmental impacts of this sector, this paper presents, for the first time, the full life cycle impacts of carbonated soft drinks manufactured and consumed in the UK. Two functional units are considered: 1 l of packaged drink and total annual production of carbonated drinks in the UK. The latter has been used to estimate the impacts at the sectoral level. The system boundary is from ‘cradle to grave’. Different packaging used for carbonated drinks is considered: glass bottles (0.75 l), aluminium cans (0.33 l) and polyethylene terephthalate (PET) bottles (0.5 and 2 l).

Materials and methods

The study has been carried out following the ISO 14040/44 life cycle assessment (LCA) methodology. Data have been sourced from a drink manufacturer as well as the CCaLC, Ecoinvent and Gabi databases. The LCA software tools CCaLC v2.0 and GaBi 4.3 have been used for LCA modelling. The environmental impacts have been estimated according to the CML 2001 method.

Results and discussion

Packaging is the main hotspot for most environmental impacts, contributing between 59 and 77 %. The ingredients account between 7 and 14 % mainly due to sugar; the manufacturing stage contributes 5–10 %, largely due to the energy for filling and packaging. Refrigeration of the drink at retailer increases global warming potential by up to 33 %. Transport contributes up to 7 % to the total impacts.

Conclusions

The drink packaged in 2 l PET bottles is the most sustainable option for most impacts, including the carbon footprint, while the drink in glass bottles is the worst option. However, reusing glass bottles three times would make the carbon footprint of the drink in glass bottles comparable to that in aluminium cans and 0.5 l PET bottles. If recycling of PET bottles is increased to 60 %, the glass bottle would need to be reused 20 times to make their carbon footprints comparable. The estimates at the sectoral level indicate that the carbonated drinks in the UK are responsible for over 1.5 million tonnes of CO2 eq. emissions per year. This represented 13 % of the GHG emissions from the whole food and drink sector or 0.26 % of the UK total emissions in 2010.  相似文献   
798.
Zinc homeostasis in the brain is associated with the etiology and manifestation of epileptic seizures. Adult Noda epileptic rats (NER, >12-week-old) exhibit spontaneously generalized tonic-clonic convulsion about once a day. To pursue the involvement of synaptic Zn2+ signal in susceptibility to spontaneous seizures, in the present study, the effect of zinc chelators on epileptogenesis was examined using adult NER. Clioquinol (CQ) and TPEN are lipophilic zinc chelotors, transported into the brain and reduce the levels of synaptic Zn2+. The incidence of tonic-clonic convulsion was markedly increased after i.p. injection of CQ (30–100 mg/kg) and TPEN (1 mg/kg). The basal levels of extracellular Zn2+ measured by ZnAF-2 were decreased before tonic-clonic convulsion was induced with zinc chelators. The hippocampal electroencephalograms during CQ (30 mg/kg)-induced convulsions were similar to those during sound-induced convulsions in NER reported previously. Exocytosis of hippocampal mossy fibers, which was measured with FM4-64, was significantly increased in hippocampal slices from CQ-injected NER that did not show tonic-clonic convulsion yet. These results indicate that the abnormal excitability of mossy fibers is induced prior to epileptic seizures by injection of zinc chelators into NER. The incidence of tonic-clonic convulsion induced with CQ (30 mg/kg) was significantly reduced by co-injection with aminooxyacetic acid (5–10 mg/kg), an anticonvulsant drug enhancing GABAergic activity, which did not affect locomotor activity. The present paper demonstrates that the abnormal excitability in the brain, especially in mossy fibers, which is potentially associated with the insufficient GABAergic neuron activity, may be a factor to reduce the threshold for epileptogenesis in NER.  相似文献   
799.

Background and Objective

The γ-secretase inhibitor (GSI) has been shown to inhibit expression of amyloid beta (Aβ), but GSI also has a side effect of reducing cell survival. Since low-power laser irradiation (LLI) has been known to promote cell survival, we examined whether 532 nm LLI can rescue the GSI side effect or not.

Study Design/Materials and Methods

The human-derived glioblastoma cells (A-172) were cultured in 35 mm culture dishes or 96-well plate. The center of dish or selected wells was irradiated with 532 nm laser (Nd:YVO4, CW, 60 mW) for 20, 40 and 60 min, respectively. The irradiated cells were photographed at immediately after, 24 and 48 h later and counted. GSI was supplemented in medium 3 h before LLI. The MTT assay was also used to estimate viable cells at 48 h after irradiation. The expression of phosphorylated Akt (p-Akt) or phosphorylated PTEN (p-PTEN) was examined by immunofluorescent staining and measured by fluorescence intensity using the software (BZ-9000, KEYENCE, Japan).

Results

GSI application depressed cell proliferation as well as cell survival compared to control. GSI down-regulated Aβ but up-regulated p-PTEN and suppressed p-Akt. Application of 532 nm LLI in the presence of GSI significantly recovered the GSI-mediated effects, i.e., LLI could decrease elevated p-PTEN, while increased p-Akt expression with keeping Aβ suppression. The LLI effects had a dose-dependency.

Conclusion

We confirmed that GSI potently suppressed intracellular Aβ and decreased cell survival. We conclude that a combination of GSI application and 532 nm LLI can increase cell proliferation via Akt activation while keeping PTEN and Aβ suppressed.  相似文献   
800.
Ingestion of a blood meal by the female mosquito Anopheles gambiae (L., Diptera: Culicidae), results in a dramatic distention of the midgut epithelium. Here, we report that these events correlate with a transient increase of actin mRNA and protein abundance. The newly synthesized actin may provide a pool of actin protein needed to remodel epithelial cell cytoarchitecture. We also document changes in midgut epithelial cell morphology. Upon blood ingestion, the columnar cells flatten accompanied by the loss of microvilli on the lumenal side and the unfolding of the labyrinth on the basal side. These changes correlate with the large increase of epithelial surface area needed to accommodate the blood meal. Actin gene expression, actin synthesis and cell morphology all return to the pre-feeding state by 24 h after blood intake.  相似文献   
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