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21.
Cells are constantly challenged by genotoxic stresses that can lead to genome instability. The integrity of the nuclear genome is preserved by the DNA damage response (DDR) and repair. Additionally, these stresses can induce mitochondria to transiently hyperfuse; however, it remains unclear whether canonical DDR is linked to these mitochondrial morphological changes. Here, we report that the abolition of mitochondrial fusion causes a substantial defect in the ATM-mediated DDR signaling. This deficiency is overcome by the restoration of mitochondria fusion. In cells with fragmented mitochondria, genotoxic stress-induced activation of JNK and its translocation to DNA lesion are lost. Importantly, the mitochondrial fusion machinery of MFN1/MFN2 associates with Sab (SH3BP5) and JNK, and these interactions are indispensable for the Sab-mediated activation of JNK and the ATM-mediated DDR signaling. Accordingly, the formation of BRCA1 and 53BP1 foci, as well as homology and end-joining repair are impaired in cells with fragmented mitochondria. Together, these data show that mitochondrial fusion-dependent JNK signaling is essential for the DDR, providing vital insight into the integration of nuclear and cytoplasmic stress signals.  相似文献   
22.
To search for candidate control agents against Aeromonas salmonicida subsp. salmonicida infections in aquaculture, one bacteriophage (phage), designated as PAS-1, was isolated from the sediment samples of the rainbow trout (Oncorhynchus mykiss) culture farm in Korea. The PAS-1 was morphologically classified as Myoviridae and possessed approximately 48 kb of double-strand genomic DNA. The phage showed broad host ranges to other subspecies of A. salmonicida as well as A. salmonicida subsp. salmonicida including antibiotic-resistant strains. Its latent period and burst size were estimated to be approximately 40 min and 116.7 PFU/cell, respectively. Furthermore, genomic and structural proteomic analysis of PAS-1 revealed that the phage was closely related to other Myoviridae phages infecting enterobacteria or Aeromonas species. The bacteriolytic activity of phage PAS-1 was evaluated using three subspecies of A. salmonicida strain at different doses of multiplicity of infection, and the results proved to be efficient for the reduction of bacterial growth. Based on these results, PAS-1 could be considered as a novel Aeromonas phage and might have potentiality to reduce the impacts of A. salmonicida infections in aquaculture.  相似文献   
23.
Microalgae are major primary producers of organic matter in aquatic environments through their photosynthetic activities. Fermented microalga (Pavlova lutheri Butcher) preparation (FMP) is the product of yeast fermentation by Hansenula polymorpha. It was tested for the antioxidant activities including lipid peroxidation inhibitory activity, free‐radical‐scavenging activity, inhibition of reactive oxygen species (ROS) on mouse macrophages (RAW264.7 cell), and inhibited myeloperoxidase (MPO) activity in human myeloid cells (HL60). FMP exhibited the highest antioxidant activity on free‐radical scavenging, inhibitory intracellular ROS, and inhibited MPO activity. MTT [3‐(4,5‐dimethyl‐2‐yl)‐2,5‐diphenyltetrazolium bromide] assay showed no cytotoxicity in mouse macrophages (RAW264.7 cell), human myeloid cells (HL60), and human fetal lung fibroblast cell line (MRC‐5). Furthermore, the antioxidative mechanism of FMP was evaluated by protein expression levels of antioxidant enzyme (superoxide dismutase [SOD] and glutathione [GSH]) using Western blot. The results obtained in the present study indicated that FMP is a potential source of natural antioxidant.  相似文献   
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25.
The present study explores the ethnic and religious identities of 21 multicultural young adults with a Japanese mother and a Korean father, all residing in South Korea where the “myth” of a mono-ethnic nation still lingers. In the study, one is considered multicultural provided they are born to both one foreign-born parent and one Korean-born parent. All interviewees are members of the Family Federation for World Peace Unification religion established in South Korea in the 1950s. Interviews with these young adults showed (a) that there was an intersectionality between their ethnic identity and religious identity; (b) that the influence of the interaction between the Church and the mother on the ethnic and religious identities of the interviewees was substantial; and (c) that they distinguished themselves from other multicultural individuals and even from non-multicultural individuals concerning their socio-economic background and transcending religious mission.  相似文献   
26.

Background

Patients with unilateral neglect fail to respond normally to stimuli on the left side. To facilitate the evaluation of unilateral spatial neglect, we developed a new application that runs on a tablet device and investigated its feasibility in stroke patients.

Methods

We made the computerized table setting test (CTST) to run on the tablet computer. Forty acute ischemic stroke patients (20 patients with right hemispheric infarction with neglect, 10 patients with right hemispheric infarction without neglect, and 10 patients with left hemispheric infarction) and 10 healthy controls were prospectively enrolled to validate the CTST. The test requires subjects to set a table by dragging 12 dishes located below the table on the tablet screen. The horizontal deviation of the 12 dishes from the midline of the table, the selection tendency measured by the sequence of the dish selection, and the elapsed time for table setting were calculated automatically.

Results

Parameters measured by the CTST were correlated with the results of conventional neglect tests. The horizontal deviation was significantly higher in patients with right hemispheric infarction with neglect compared with the other groups. The selection tendency and elapsed time also were significantly different in patients with right hemispheric infarction with neglect compared with the left hemispheric infarction and control groups, but were similar to those with right hemispheric infarction without neglect.

Conclusions

The CTST is feasible to administer and comparable with conventional neglect tests. This new application may be useful for the initial diagnosis and follow-up of neglect patients.  相似文献   
27.
The transmission/disequilibrium test (TDT) developed by Spielman et al. can be a powerful family-based test of linkage and, in some cases, a test of association as well as linkage. It has recently been extended in several ways; these include allowance for implementation with quantitative traits, allowance for multiple alleles, and, in the case of dichotomous traits, allowance for testing in the absence of parental data. In this article, these three extensions are combined, and two procedures are developed that offer valid joint tests of linkage and (in the case of certain sibling configurations) association with quantitative traits, with use of data from siblings only, and that can accommodate biallelic or multiallelic loci. The first procedure uses a mixed-effects (i.e., random and fixed effects) analysis of variance in which sibship is the random factor, marker genotype is the fixed factor, and the continuous phenotype is the dependent variable. Covariates can easily be accommodated, and the procedure can be implemented in commonly available statistical software. The second procedure is a permutation-based procedure. Selected power studies are conducted to illustrate the relative power of each test under a variety of circumstances.  相似文献   
28.
The hybrid cluster protein (HCP; formerly termed the prismane protein) has been extensively studied due to its unique spectroscopic properties. Although the structural and spectroscopic characteristics are well defined, its enzymatic function, up to this point, has remained unidentified. While it was proposed that HCP acts in some step of nitrogen metabolism, a specific role for this enzyme remained unknown. Recent studies of HCP purified from Escherichia coli have identified a novel hydroxylamine reductase activity. These data reveal the ability of HCP to reduce hydroxylamine in vitro to form NH(3) and H(2)O. Further biochemical analyses were completed in order to determine the effects of various electron donors, different pH levels, and the presence of CN(-) on in vitro hydroxylamine reduction.  相似文献   
29.
This study was aimed to search new genetic variants in the bovine FABP4 gene as molecular markers for meat quality and carcass traits. PCR–RFLP analysis revealed that three SNPs located at nucleotide positions g.2834C>G, g.3533T>A, and g.3691G>A were identified based on a GenBank accession number (NC_007312.4). Sequence analysis revealed that SNPs were located in intron 1 (g.2834C>G) and 2 (g.3533T>A), and an exon 3 (g.3691G>A), showing allele frequencies as 0.592, 0.579, and 0.789, respectively. Genetic variabilities of heterozygosity (He) and polymorphic information contents (PIC) were estimated for g.2834C>G (0.608 and 0.531), g.3533T>A (0.615 and 0.539), and g.3691G>A (0.498 and 0.401) loci, respectively. A SNP located in the exon 3 of FABP4 was characterized and associated with desirable increases of MS (marbling scores) and MG (meat quality grades) in Hanwoo. The statistical analysis revealed that additive effects by GG genotypes in g.3691G>A SNP were significantly greater than AA genotypes in MS and MG traits. These findings suggest that the FABP4g.3691G>A SNP will be a useful candidate locus to maximize economic benefits for cattle populations.  相似文献   
30.
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