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981.
Photoinduced H2 production with Mg chlorophyll-a from Spirulina as a visible light photosensitizer by use of a three component system consisting of NADPH as an electron donor, Methyl Viologen as electron relay and colloidal platinum as catalyst was investigated. By using this system, the H2 production rate was estimated to be 0.70 ± 0.03 × 10–6 mol h–1.  相似文献   
982.
Four tyrosine-protein kinases that reacted with antibodies specific to p62c-yes, p60c-src, p60c-src+, and p59fyn, respectively, were solubilized from a rat brain particulate fraction and separated by casein-Toyopearl column chromatography. Possible p59fyn, with a pI of 6.5, was purified 490-fold as a single 59-kDa protein band on SDS-PAGE. The purified enzyme contained almost no phosphotyrosine residues but was autophosphorylated with Mg2+. ATP exclusively at tyrosine residues, with a concomitant increase in the kinase activity toward tyrosine-glutamate (1:4) copolymers. The rate of the copolymer phosphorylation was proportional to the square of the enzyme concentration, suggesting activation through intermolecular catalysis. In the presence of Mn2+, however, the reaction showed a first-order dependence on the enzyme concentration.  相似文献   
983.
Deformities in cultured fish species may be genetic, and identifying causative genes is essential to expand production and maintain farmed animal welfare. We previously reported a genetic deformity in juvenile red sea bream, designated a transparent phenotype. To identify its causative gene, we conducted genome-wide linkage analysis and identified two single nucleotide polymorphisms (SNP) located on LG23 directly linked to the transparent phenotype. The scaffold on which the two SNPs were located contained two candidate genes, duox and duoxa, which are related to thyroid hormone synthesis. Four missense mutations were found in duox and one in duoxa, with that in duoxa showing perfect association with the transparent phenotype. The mutation of duoxa was suggested to affect the transmembrane structure and thyroid-related traits, including an enlarged thyroid gland and immature erythrocytes, and lower thyroxine (T4) concentrations were observed in the transparent phenotype. The transparent phenotype was rescued by T4 immersion. Loss-of-function of duoxa by CRISPR–Cas9 induced the transparent phenotype in zebrafish. Evidence suggests that the transparent phenotype of juvenile red sea bream is caused by the missense mutation of duoxa and that this mutation disrupts thyroid hormone synthesis. The newly identified missense mutation will contribute to effective selective breeding of red sea bream to purge the causative gene of the undesirable phenotype and improve seed production of red sea bream as well as provide basic information of the mechanisms of thyroid hormones and its related diseases in fish and humans.Subject terms: Agricultural genetics, Animal breeding  相似文献   
984.
Glycosyltransferase complexes are known to be involved in plant cell wall biosynthesis, as for example in cellulose. It is not known to what extent such complexes are involved in biosynthesis of pectin as well. To address this question, work was initiated on ARAD1 (ARABINAN DEFICIENT 1) and its close homolog ARAD2 of glycosyltransferase family GT47. Using bimolecular fluorescence complementation, Förster resonance energy transfer and non-reducing gel electrophoresis, we show that ARAD1 and ARAD2 are localized in the same Golgi compartment and form homo-and heterodimeric intermolecular dimers when expressed transiently in Nicotiana benthamiana. Biochemical analysis of arad2 cell wall or fractions hereof showed no difference in the monosaccharide composition, when compared with wild type. The double mutant arad1 arad2 had an arad1 cell wall phenotype and overexpression of ARAD2 did not complement the arad1 phenotype, indicating that ARAD1 and ARAD2 are not redundant enzymes. To investigate the cell wall structure of the mutants in detail, immunohistochemical analyses were carried out on arad1, arad2 and arad1 arad2 using the arabinan-specific monoclonal antibody LM13. In roots, the labeling pattern of arad2 was distinct from both that of wild type, arad1 and arad1 arad2. Likewise, in epidermal cell walls of inflorescence stems, LM13 binding differed between arad2 and WILD TYPE, arad1 or arad1 arad2. Altogether, these data show that ARAD2 is associated with arabinan biosynthesis, not redundant with ARAD1, and that the two glycosyltransferases may function in complexes held together by disulfide bridges.  相似文献   
985.
The flagellar axial component proteins are exported to the distal end of the growing flagellum for self-assembly by the flagellar type III export apparatus. FlhA is a key membrane protein of the export apparatus, and its C-terminal cytoplasmic domain (FlhAC) is a part of an assembly platform for the three soluble export components, FliH, FliI, and FliJ, as well as export substrates and chaperone–substrate complexes. FlhAC is composed of a flexible linker region and four compact domains (ACD1–ACD4). At 42 °C, a temperature-sensitive (TS) G368C mutation in FlhAC blocks the export process after the FliH–FliI–FliJ–substrate complex binds to the assembly platform, but it remains unknown how it does so. In this study, we analyzed a TS mutant variant, FlhAC(G368C), and its pseudorevertant variants FlhAC(G368C/L359F), FlhAC(G368C/G364R), FlhAC(G368C/R370S), and FlhAC(G368C/P550S) using far-ultraviolet circular dichroism. Whereas the denaturation of the wild-type FlhAC occurs in a single step, FlhAC(G368C) and its pseudorevertant variants showed thermal transitions, at least, in two steps. The first transition of FlhAC(G368C) can further be divided into reversible and following irreversible transitions, which correspond to the denaturation of ACD2 and ACD1, respectively. We show the relation between the reversible transition and the TS defect in the exporting function of FlhAC(G368C) and that the loss of function is caused by denaturation of ACD2. We suggest that ACD2 is directly involved in the translocation of export substrates.  相似文献   
986.
987.
Since Factor Xa (FXa) is well known to play a central role in thrombosis and hemostasis, inhibition of FXa is an attractive target for antithrombotic strategies. As a part of our investigation of a non-peptide, orally available FXa inhibitor, we found that a series of N-[(7-amidino-2-naphthyl)methyl]aniline derivatives possessed potent and selective inhibitory activities. Structure--activity relationship (SAR) of the substituent (R(1)) on the central aniline moiety suggested that increasing lipophilicity caused a detrimental effect on anticoagulant activity (prothrombin time assay) in plasma. Several compounds bearing a hydrophilic substituent in R(1) showed not only potent FXa inhibitory activities but also high anticoagulant activities. The best compound in this series was sulfamoylacetic acid derivative (YM-60828) which was a potent, selective and orally bioavailable FXa inhibitor and was chosen for clinical development.  相似文献   
988.
Oral malodor is considered to originate primarily from tongue microbiota populations. However, the relationship between oral malodor and tongue microbiota remains unclear. In this study, tongue periodontal pathogens were analyzed via real-time PCR, and the association between oral malodor and tongue periodontal pathogens, including Porphyromonas gingivalis, Tannerella forsythia, Prevotella intermedia, Prevotella nigrescens and Treponema denticola, was examined. The subject population consisted of 29 individuals with and 10 healthy persons without oral malodor. Oral malodor was assessed by organoleptic test and volatile sulfur compound (VSC) levels as measured by gas chromatography. Real-time PCR was conducted for anaerobes in tongue biofilm samples employing a LightCycler system; furthermore, bacterial proportion served as a quantitative parameter. Among the five anaerobes, only T. forsythia displayed higher proportions in malodor subjects than corresponding values in healthy controls. Proportions of P. intermedia and P. nigrescens correlated strongly with hydrogen sulfide concentration. Proportions of P. gingivalis and P. nigrescens also exhibited strong correlation with methyl mercaptan concentration. The correlation coefficient between the proportion of the total of the five anaerobes and total VSC level (r = 0.88) was greater than that between bacterial proportion and organoleptic score (r = 0.29). When a linear regression analysis was performed utilizing the proportion of each of the five periodontal pathogens as an independent variable, the explanatory power of these independent variables revealed 81% for total VSC level and 16% for organoleptic score. These results suggest that these five periodontal pathogens on tongue dorsa may contribute greatly to VSC production.  相似文献   
989.
The inter-residual dihedral angles phi and phip of chitin and chitosan oligomers were determined from experimental 3J(C-H) constants and ROESY cross peaks.  相似文献   
990.

Background

The relationship between perceived rearing and the postpartum depressive state remains unclear. We aimed to examine whether perceived rearing is a risk factor for postpartum depression as measured by the Edinburgh Postnatal Depression Scale (EPDS), and whether the score of perceived rearing is affected by depressive mood (the state dependency of perceived rearing).

Methods

Pregnant women (n = 448, mean age 31.8±4.2 years) completed the EPDS as a measure of depressive state in early pregnancy (T1), late pregnancy (around 36 weeks), and at 1 month postpartum (T2), and the Parental Bonding Instrument (PBI) at T1 as a measure of perceived rearing. Changes in the EPDS and the PBI scores from T1 to T2 were compared between the non depressive (ND) group and the postpartum depressive (PD) group.

Results

There were no significant differences in any PBI category for perceived rearing between the ND and PD groups at T1. EPDS scores did not change significantly from T1 to T2 in the ND group but increased significantly in the PD group. The PBI maternal care score increased significantly in the ND group (p<0.01), while decreasing in the PD group (p<0.05). Additionally, in both the ND and PD groups, significant negative correlation was observed regarding change in the EPDS and PBI maternal care scores from T1 to T2 (r = −0.28, p = 0.013).

Conclusions

The present study suggests that perceived rearing is not a strong risk factor for postpartum depression as measured by the EPDS. Furthermore, the results indicated the state dependency of the PBI maternal care score.  相似文献   
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