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161.
This study developed gate‐to‐gate life cycle inventory (LCI) data for the repair of 48 by 40 inch (1,219 by 1,016 millimeter [mm]) stringer‐class wood pallets in the United States. Data were collected from seven wood pallet repair facilities. Approximately 1.98 FBM (foot, board measure) (4.67E‐03 cubic meters) of lumber were used for repairing each 48 by 40 inch (1,219 by 1,016 mm) stringer‐class wood pallet, the majority (97%) recovered from damaged pallets received by the pallet repair facilities. Repair equipment powered by electricity made the largest contribution to greenhouse gas (GHG) emissions. Steel nails used for the pallet repair had the largest contribution to GHG emissions among the material inputs, while use of recovered lumber yielded the largest GHG emissions credits. Overall, the repair process for a 48 by 40 inch (1,219 by 1,016 mm) stringer‐class wood pallet had GHG credits rather than a positive GHG emission due to the GHG offsets from co‐products. 相似文献
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163.
Dora Ravasz Gergely Kacso Viktoria Fodor Kata Horvath Vera Adam-Vizi Christos Chinopoulos 《BBA》2018,1859(9):909-924
Provision of NAD+ for oxidative decarboxylation of alpha-ketoglutarate to succinyl-CoA by the ketoglutarate dehydrogenase complex (KGDHC) is critical for maintained operation of succinyl-CoA ligase yielding high-energy phosphates, a process known as mitochondrial substrate-level phosphorylation (mSLP). We have shown previously that when NADH oxidation by complex I is inhibited by rotenone or anoxia, mitochondrial diaphorases yield NAD+, provided that suitable quinones are present (Kiss G et al., FASEB J 2014, 28:1682). This allows for KGDHC reaction to proceed and as an extension of this, mSLP. NAD(P)H quinone oxidoreductase 1 (NQO1) is an enzyme exhibiting diaphorase activity. Here, by using Nqo1?/? and WT littermate mice we show that in rotenone-treated, isolated liver mitochondria 2-methoxy-1,4-naphtoquinone (MNQ) is preferentially reduced by matrix Nqo1 yielding NAD+ to KGDHC, supporting mSLP. This process was sensitive to inhibition by specific diaphorase inhibitors. Reduction of idebenone and its analogues MRQ-20 and MRQ-56, menadione, mitoquinone and duroquinone were unaffected by genetic disruption of the Nqo1 gene. The results allow for the conclusions that i) MNQ is a Nqo1-preferred substrate, and ii) in the presence of suitable quinones, mitochondrially-localized diaphorases other than Nqo1 support NADH oxidation when complex I is inhibited. Our work confirms that complex I bypass can occur by quinones reduced by intramitochondrial diaphorases oxidizing NADH, ultimately supporting mSLP. Finally, it may help to elucidate structure-activity relationships of redox-active quinones with diaphorase enzymes. 相似文献
164.
Identification of an immediate-early salicylic acid-inducible tobacco gene and characterization of induction by other compounds 总被引:2,自引:0,他引:2
Tobacco genes that are induced in response to salicylic acid (SA) treatment with immediate-early kinetics were identified by differential mRNA display. Detailed analysis of IS10a, one cDNA clone identified by this method, revealed induction within 30 min of treatment, with a peak of expression at 3 h, that decayed rapidly thereafter. Treatment with the protein synthesis inhibitor, cycloheximide (CHX), also caused induction of IS10a mRNA to comparable levels, but the IS10a mRNA continued to accumulate after 3 h of induction. In combination, CHX and SA led to a superinduction of IS10a mRNA levels that was also sustained. Half-maximal induction was evident at ca. 100–150 M SA. In addition to SA, induction of IS10a occurred to varying degrees upon treatment with acetylsalicylic acid, benzoic acid, 2,4-dichlorophenoxyacetic acid, methyl jasmonate, and hydrogen peroxide, whereas treatment with other compounds had no effect. The proteins encoded by IS10a and a second highly homologous cDNA show sequence similarity to UDP-glucose: flavonoid glucosyltransferases.Abbreviations 2,4-D
2,4-dichlorophenoxyacetic acid
- 4HBA
4-hydroxybenzoic acid
- aa
amino acid
- bp
base pair
- nt
nucleotide
- ASA
acetyl salicylic acid
- BA
benzoic acid
- CHX
Cycloheximide
- MJ
methyl jasmonate
- PCR
polymerase chain reaction
- SA
salicylic acid
- TMV
tobacco mosaic virus 相似文献
165.
166.
Identification of a species-specific inhibitor of glycosylphosphatidylinositol synthesis. 总被引:5,自引:0,他引:5
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C Sütterlin A Horvath P Gerold R T Schwarz Y Wang M Dreyfuss H Riezman 《The EMBO journal》1997,16(21):6374-6383
Glycosylphosphatidylinositol (GPI)-anchoring represents a mechanism for attaching proteins to the cell surface that is used among all eukaryotes. A common core structure, EthN-P-Man3-GlcN-PI, is synthesized by sequential transfer of sugars and ethanolamine-P to PI and is highly conserved between organisms. We have screened for natural compounds that inhibit GPI-anchoring in yeast and have identified a terpenoid lactone, YW3548, that specifically blocks the addition of the third mannose to the intermediate structure Man2-GlcN-acyIPI. Consistent with the block in GPI synthesis, YW3548 prevents the incorporation of [3H]myo-inositol into proteins, transport of GPI-anchored proteins to the Golgi and is toxic. The compound inhibits the same step of GPI synthesis in mammalian cells, but has no significant activity in protozoa. These results suggest that despite the conserved core structure, the GPI biosynthetic machinery may be different enough between mammalian and protozoa to represent a target for anti-protozoan chemotherapy. 相似文献
167.
Fine structural investigation of surgically removed human pituitary and parathyroid adenomas, pheochromocytomas and bronchial carcinoids revealed a hitherto undetected sequence of events in the formation of centrioles and cilia indicating that mitochondria may serve as their progenitors. The first steps seem to be the disappearance of mitochondrial cristae and a polar accumulation of a fibrillar-granular material with a subsequent increase of electron density of the double mitochondrial membranes and deposition of more electron opaque substance within and around these procentriolar bodies. This process is followed by the disintegration of the double membranes and an asymmetrical division of the electron dense aggregate. The larger part seems to be the precursor of the primary centriole (basal body) whereas the smaller one that of the secondary centriole. Formation of centrioleand rudimentary cilium-like structures was disclosed within the unaltered mitochondrial membranes of oncocytic cells present in two pituitary adenomas and in one pheochromocytoma. Accumulation of procentriolar bodies and mature centrioles, noted in some tumors, may be due to a defect in the process of centriolo- and ciliogenesis. It is conceivable that the mitochondrial genome plays an important role in formation of centrioles and cilia. 相似文献
168.
169.
Twelve nontumorous adenohypophyses and 36 various pituitary adenomas, removed by surgery, have been investigated by electron microscopy in order to shed some light on annulate lamellae, primarily on their ultrastructural features, incidence, origin, fate and functional significance. No annulate lamellae were found in the nontumorous adenohypophyses and in 33 pituitary adenomas. They were, however, detected in two adenomas consisting of undifferentiated cells and one adenoma composed of sparsely granulated prolactin cells indicating that these unique membrane configurations cannot be regarded as an exceedingly rare finding and, furthermore, that they may be disclosed not only in undifferentiated but occasionally in highly differentiated cells. Annulate lamellae may arise from endoplasmic reticulum and/or nuclear envelope and consist of arrays of smooth walled double membrane sheets exhibiting regularly spaced interruptions as well as continuities with the endoplasmic reticulum. No relationship was established between annulate lamellae and adenohypophysial secretory activity. Our findings seem to be consistent with the view that annulate lamellae are present in those cells which have the tendency to proliferate. 相似文献
170.