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131.
Mouse mast cell protease 11 (mMCP-11) is the most recently identified member of the mouse mast cell tryptase family. This tryptase is preferentially produced by basophils in contrast to other members that are expressed by mast cells but not basophils. Although blood-circulating basophils have long been considered as minor and redundant relatives of tissue-resident mast cells, recent studies illustrated that basophils and mast cells play distinct roles in vivo. To explore the in vivo role of basophil-derived mMCP-11, here we prepared recombinant mMCP-11 and its protease-dead mutant. Subcutaneous injection of the wild-type mMCP-11 but not the mutant induced edematous skin swelling with increased microvascular permeability in a dose-dependent manner. No apparent infiltration of proinflammatory cells including neutrophils and eosinophils was detected in the skin lesions. The cutaneous swelling was abolished by the pretreatment of mice with indomethacin, a cyclooxygenase inhibitor, suggesting the major contribution of prostaglandins to the microvascular leakage. Of note, the cutaneous swelling was elicited even in mast cell-deficient mice, indicating that mast cells are dispensable for the mMCP-11-induced cutaneous swelling. Thus, basophil-derived mMCP-11 can induce microvascular leakage via prostaglandins in a mast cell-independent manner, and may contribute to the development of basophil-mediated inflammatory responses.  相似文献   
132.
Cyanidioschyzon merolae (Cm) is a single-cell red alga that grows under moderately thermophilic (40-50°C), acidic (pH 1-3) conditions. We purified a Cm ferredoxin (Fd) that was characterized as a plant-type [2Fe-2S] Fd by physicochemical techniques. X-ray crystallography revealed that the overall three-dimensional structure of CmFd was highly similar to, but slightly different from, the [2Fe-2S] Fd from Spinacia oleracea, whose growth temperature is 15-20°C. Therefore, slight structural differences, including non-covalent-bond number and amino acid sequence, may underlie the differential thermostabilities of the plant-type Fds.  相似文献   
133.
134.
Sequence analysis of the VP7 gene in 23 group A human rotavirus G2P[4] strains obtained during 1991–2011, that is, the pre‐vaccine era, in Sapporo, Japan showed considerable genetic diversity, mainly in variable regions. Recent G2P[4] epidemic strains were located in sublineage IVa with a distinctive substitution of D96N. This study provides background data on the genetic variability of G2P[4] rotavirus‐VP7 gene prior to the widespread use of rotavirus vaccines in Japan.  相似文献   
135.
Bacteria degrading a very long-chain alkane, n-tetracosane, were isolated from enrichment culture of soil in Okinawa. Phylogenetic analysis of their16S rRNA sequences revealed that they belong to classes Gammaproteobacteria and Actinomycetes. Three isolates belonging to the genera Acinetobacter sp., Pseudomonas sp., and Gordonia sp. showed a stable growth on n-tetracosane and had a wide range of assimilation of aliphatic hydrocarbons from C12 to C30, while not on alkanes shorter than C8. Of the isolates, Gordonia sp. degraded oil tank sludge hydrocarbons efficiently by solving the sludge in a hydrophobic solvent, while Acinetobacter sp. showed little degradation, possibly due to the difference in the mechanism of hydrophobic substrate incorporation between proteobacteria and actinobacteria. The data suggested that non-heme di-iron monooxygenases of the AlkB-type, not bacterial CYP153 type cytochrome P450 alkane hydroxylase, was involved in the alkane degradation.  相似文献   
136.

Purpose

Being bullied is associated with the manifestation of suicidal feelings, which sharply increase in middle(-late) adolescence. Whether or not bullied middle(-late) adolescents with suicidal feelings seek help is therefore a critical issue, given that help-seeking plays a key role in the prevention of suicide. The aim of the present study is to investigate the effects of bullying, suicidal feelings and the interaction between these two factors on help-seeking behavior in adolescents.

Methods

Japanese middle(-late) adolescents (aged 15–18 years; n = 9484) were studied using self-report questionnaires. The rate of adolescents who actually sought help was examined for bullying status and suicidal feelings.

Results

The rate of adolescents who sought help was significantly higher when they were bullied (p<0.001) and also when they had mild suicidal feelings (p<0.001), but not when they displayed serious suicidal feelings. In the case of adolescents who were bullied, however, having suicidal feelings significantly decreased the rate of help-seeking (OR = 0.47, p<0.05 and OR = 0.32, p = 0.002 for having mild and serious suicidal feelings, respectively). The decrease was remarkable when suicidal feelings were serious. Specifically, the decrease was significant in seeking help from peers and family members, who are the most frequent source of the help for adolescents, when they had serious suicidal feelings (OR = 0.21, p<0.01 and OR = 0.13, p<0.001, respectively).

Conclusions

Suicidal feelings may interfere with help-seeking behavior, which could be critical in suicide prevention in bullied middle(-late) adolescents.  相似文献   
137.
Unlike other important Solanaceae crops such as tomato, potato, chili pepper, and tobacco, all of which originated in South America and are cultivated worldwide, eggplant (Solanum melongena L.) is indigenous to the Old World and in this respect it is phylogenetically unique. To broaden our knowledge of the genomic nature of solanaceous plants further, we dissected the eggplant genome and built a draft genome dataset with 33,873 scaffolds termed SME_r2.5.1 that covers 833.1 Mb, ca. 74% of the eggplant genome. Approximately 90% of the gene space was estimated to be covered by SME_r2.5.1 and 85,446 genes were predicted in the genome. Clustering analysis of the predicted genes of eggplant along with the genes of three other solanaceous plants as well as Arabidopsis thaliana revealed that, of the 35,000 clusters generated, 4,018 were exclusively composed of eggplant genes that would perhaps confer eggplant-specific traits. Between eggplant and tomato, 16,573 pairs of genes were deduced to be orthologous, and 9,489 eggplant scaffolds could be mapped onto the tomato genome. Furthermore, 56 conserved synteny blocks were identified between the two species. The detailed comparative analysis of the eggplant and tomato genomes will facilitate our understanding of the genomic architecture of solanaceous plants, which will contribute to cultivation and further utilization of these crops.  相似文献   
138.
The activity of 3-deoxy-D-arabino-heptulosonate 7-phosphate (DAHP) synthase (DS-Mn, DS-Co), phenylalanine ammonia-lyase (PAL), and chalcone synthase (CHS) was monitored at various light intensities (dark, 8.88 μmol m−2 s−1, 88.8 μmol m−2 s−1) using a strawberry cell suspension culture. DS-Mn, PAL, and CHS were found to increase significantly (p>0.05) under light intensitie of 88.8 μmol m−2 s−1 compared to those of 8.88 μmol m−2 s−1 and dark. The activity of DS-Mn, PAL, and CHS were maximum at 88.8 μmol m−2 s−1. Anthocyanin content reached a maximum after 48–60 h of culturing at 88.8 μmol m−2 s−1. DS-Co showed greater activity than DS-Mn during cell culturing, but showed no correlation with anthocyanin production and light intensity. The CHS gene expression was continuous at a light intensity of 88.8 μmol m−2 s−1. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   
139.
The Structure and Distribution of the Flavonoids in Plants   总被引:17,自引:0,他引:17  
6 -C3-C6 skeleton, have been found in plants, and are divided into several classes, i.e., anthocyanins, flavones, flavonols, flavanones, dihydroflavonols, chalcones, aurones, flavan and proanthocyanidins, isoflavonoids, biflavonoids, etc. In this review, the chemical structures of the reported flavonoid classes are introduced and their distribution in nature are described. Additionally, some recent chemotaxonomical examples using the flavonoids are also given. Received 1 June 2000/ Accepted in revised form 1 July 2000  相似文献   
140.
We sought to determine whether a 6-week exposure to a 50-Hz rotating magnetic field influences melatonin synthesis by 11–18 week-old Wistar-King male rats. Rats were exposed continuously to a rotating magnetic field at 1, 5, 50, or 250 μT (spatial vector rms) for 6 weeks, except for twice-weekly breaks of about 2 h for cleaning of cages and feeding. The rats were housed in exposure and sham-exposure facilities, which were located in the same room, under a 12:12 light-dark photoperiod (lights on at 06:00 h). The room was constantly illuminated by 4 small, dim red lights (< 0.07 lux in dark period). Levels of plasma and pineal gland melatonin were determined by radioimmunoassay. A significant decrease of melatonin was observed between the control group and groups exposed to a magnetic field at a flux density in excess of l μT during the night time, but no statistical differences were found among the exposed groups. These results indicate that subchronic exposure of albino rats to a 50-Hz rotating magnetic field influences melatonin production and secretion by the pineal gland. © 1993 Wiley-Liss, Inc.  相似文献   
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