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331.
Human immunoglobulin G (IgG) concentrates are immune-modulating, anti-inflammatory plasma-derived products. Clinical studies in recent years have suggested that IgG attenuates neuropathic pain. In this study, effects of sulphonated IgG on the development and maintenance of a mechanical allodynia-like response were examined in mice with neuropathic pain induced by a partial sciatic nerve ligation (PSL). When sulphonated IgG (400 or 1,000 mg/kg/day, i.p.) was administered for 5 days, from 1 day before surgery to post-operative day (POD) 3, the development of a mechanical allodynia-like response was attenuated. On the other hand, sulphonated IgG had little effect on the maintenance of a mechanical allodynia-like response when administered for 5 days, from POD 11 to POD 15, at which time a mechanical allodynia-like response had already been developed. To explore the mechanism of sulphonated IgG, the mRNA expression of inflammatory cytokines was evaluated in the injured sciatic nerve. Sulphonated IgG (1,000 mg/kg/day, i.p.) that was administered for 3 days, from 1 day before surgery to POD 1, significantly attenuated the up-regulation of tumor necrosis factor-α and monocyte chemotactic protein-1 mRNAs on POD 1. These results suggest that prophylactic treatment with sulphonated IgG attenuates the development of mechanical allodynia-like response by inhibition of inflammatory cytokine expression in mice with PSL.  相似文献   
332.
Natural intoxication of livestock by the ingestion of Ipomoea carnea (Convolvulaceae) sometimes occurs in tropical regions of the world. Polyhydroxylated alkaloids were isolated from the leaves, flowers, and seeds of the poisonous plant and characterized. Chromatographic separation of the leaf extract resulted in the isolation of swainsonine (1), 2-epi-lentiginosine (2), calystegines B(1) (3), B(2) (4), B(3) (5), and C(1) (6), and N-methyl-trans-4-hydroxy-l-proline (7). The contents of 1 in the fresh leaves and flowers were 0.0029 and 0.0028%, respectively, whereas the contents of 1, 3, and 4 in the seeds were approximately 10 times higher than those in the leaves and flowers. Alkaloids 3, 4, and 6 showed a potent inhibitory activity toward rat lysosomal beta-glucosidase, with IC(50) values of 2.1, 0.75, and 0.84 microM, respectively, and alkaloid 5 was a moderate inhibitor of alpha- and beta-mannosidases. Although alkaloid 1 is known as a powerful inhibitor of lysosomal alpha-mannosidase (IC(50) = 0.02 microM), alkaloid 2, which has been thought to be an intermediate in the biosynthesis of 1, was also a potent inhibitor of alpha-mannosidase with an IC(50) value of 4.6 microM.  相似文献   
333.
334.
Two cases of spontaneous focal hepatic hyperplasia were observed in young female cynomolgus macaques (Macaca fascicularis). Grossly, a single raised nodule was observed in the left hepatic lobe. Histopathologically, the nodule compressed surrounding normal tissue; however, the hepatic cords within the nodule continued to those in the nor mal area except in part. Extensive fibrosis and absence of a normal hepatic triad were observed in the nodule. Thin fibrous septa radiating from the dense central stellate scarring and distended vessels were apparent in one animal. Hepatocytes in the nodule lacked cellular atypia, showed frequent PAS-positive eosinophilic inclusions in the cytoplasm and showed higher positive ratios for PCNA. The present cases resembled focal nodular hyperplasia reported in humans and a chimpanzee.  相似文献   
335.
336.
We investigated radiocesium distribution in tea plants (Camellia sinensis L. var. sinensis) of Saitama Prefecture, located approximately 200–250 km away from Tokyo Electric Power Company’s Fukushima Daiichi nuclear power plant. In 2012, more than 2500 samples of tea plants were analyzed. We found differences in radiocesium concentration among tea plant cultivars, which appeared to be attributable mainly to the leaf morphology and depth of the leaf layer in tea plants. Furthermore, the radiocesium concentration in the first tea crop showed a strong correlation with that in spring skiffing.  相似文献   
337.
ABSTRACT

Legumes, including hairy vetch (Vicia villosa Roth), are widely used as green manures. They fix nitrogen (N) and provide the N to other crops when they decompose, and thus are considered alternatives for chemical N fertilizers. However, N-rich plant residues, including hairy vetch, are also sources of soil nitrous oxide (N2O) emissions, a greenhouse gas. On one hand, rice (Oryza sativa L. ssp. japonica) husk biochar is widely used as a soil conditioner in Japan and has been reported as a tool to mitigate soil N2O emissions. We conducted a soil core incubation experiment (1.5 months) to compare the N2O emissions during the decomposition of surface-applied hairy vetch (0.8 kg dried hairy vetch m?2 soil) under semi-saturated soil moisture conditions (~100% water-filled pore space (WFPS)), using two soil types, namely Andosol and Fluvisol. Throughout the incubation period, the use of biochar suppressed soil NH4+-N concentrations in Andosol, whereas the effect of biochar on NH4+-N was not clear in Fluvisol. Biochar increased the nitrate (NO3?-N) levels both in Andosol and Fluvisol, suggesting a negative influence on denitrification and/or a positive influence on nitrification. Biochar application did not influence the cumulative N2O emissions. Our study suggests that rice husk biochar is not a good option to mitigate N2O emissions during the decomposition of surface-applied hairy vetch, although this study was performed under laboratory conditions without plants. However, the trends of the inorganic-N concentration changes followed by the addition of hairy vetch and biochar were markedly different between the two soil types. Thus, factors behind the differences need to be further studied.  相似文献   
338.
Relationships between abiotic oxidation and adsorption of phenolic acids added to soils and soil chemical properties were investigated by using 32 soil samples and ferulic, vanillic, and p-hydroxybenzoic acids. Soil properties studied were as follows: (as adsorption factors) contents of acid oxalate extractable Al (Alo), Fe (Feo), dithionite-citrate-bicarbonate (DCB) extractable Fe (Fed), total carbon and clay, and (as oxidation factors) level of soil oxidative activity (Cr oxidation) determined by the amount of Cr(VI) converted from Cr(III) added to soils. Soil samples were divided into 3 types based on chemical properties: Andosols A (A horizon of Andosols), Andosols B (B horizon of Andosols and light-colored Andosols), and non-Andosols.

The recovery of all phenolic acids (RPA) was negatively correlated with the total carbon and Feo contents in Andosols A and B, respectively, which suggested adsorption onto soil organic matter in Andosols A and onto Feo in Andosols B. It was considered that almost no oxidation of phenolic acids occurred in Andosols A, because a very small amount of Cr(VI) was obtained. The recovery of ferulic acid (RFA) and vanillic acid (RVA), however, was negatively correlated with Cr oxidation in non-Andosols, suggesting that these phenolic acids were oxidized, while almost all of the p-hydroxybenzoic acid was recovered.

These results were also supported by the comparison between RFA and recovery of dissolved organic carbon (RTOC). RFA was very similar to RTOC in Andosols A and B, which indicated that adsorption occurred, whereas RFA was lower than RTOC in the non-Andosols that showed a high level of Cr oxidation, indicating that oxidation took place. Manganese dissolution which occurred when phenolic acids were added to soils was also examined.  相似文献   
339.
A pot experiment was conducted under growth chamber conditions to determine the lower and upper critical levels of boron (B) for plant growth, nodule development, and nodule acetylene reduction activity (ARA) in young soybean plants. Plants of a soybean cultivar, Tachinagaha, were grown in pots containing river sand to which a nutrient solution with different B levels was added and were inoculated with Bradyrhizobium japonicum A1017. At 8, 12, and 16 d after sowing (DAS), among the plants supplied with the solution at 0, 1.0, and 2.0 mg B L-1 , plants with 1.0 mg B L-1 showed the highest values for dry shoot and fresh root weight, root length, total number of developing nodules and meristematic nodules (DMN), and ARA. At 20 DAS plants grown with 11 B levels (0-2.0 mg L-1) were compared. The B critical deficiency levels for soybean dry shoot weight, fresh root weight, root length, DMN, number of complete nodules, and ARA were approximately 46, 35, 34, 57, 60, and 50 mg B kg-1 dry matter, and the critical toxicity levels were approximately 114, 137, 134, 97, 104, and 89 mg B kg-1 dry matter, respectively. The optimum B levels for the growth characters were approximately 34 to 137 mg B kg-1 dry matter. The optimum range of B levels for nodule formation and function was more restricted than that for the growth characters. Based on the results of treatments with various B concentrations, 0.4 mg B L-1 was found to be the concentration most beneficial for all the growth characters including nodule formation at the early stage (20 DAS) of development of soybean plants.  相似文献   
340.
Endophytic bacteria were isolated from the juice of a 6 month-old sugarcane cv. NiF-8, which was collected from Miyako, Okinawa and planted in a field lysimeter in Tsukuba, Ibaraki, Japan. The most probable number of N2-fixing endophytes was 4.5 × 105 cells per gram of fresh weight sample and 21 isolates have a positive reaction for ARA in an N2-free semi-solid medium with 10% crystallized sugarcane sugar and 0.5% sugarcane juice. Analyses of some of the biochemical properties of the N2-fixing isolates indicated that 13 isolates were putative strains of Acetobacter diazotrophicus, 4 isolates showed similar characteristics to those of Herbaspirillum seropedicae, and 4 isolates consisted of Herbaspirillum rubribalbicans-like strains. This study confirmed the existence of N2-fixing endophytic bacteria in the Japanese sugarcane cv. NiF-8.  相似文献   
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