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101.
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103.
Ito M Nakajima S Fujisawa D Miyashita M Kim Y Shear MK Ghesquiere A Wall MM 《PloS one》2012,7(2):e31209
Background
Complicated grief, which is often under-recognized and under-treated, can lead to substantial impairment in functioning. The Brief Grief Questionnaire (BGQ) is a 5-item self-report or interview instrument for screening complicated grief. Although investigations with help-seeking samples suggest that the BGQ is valid and reliable, it has not been validated in a broader population.Methodology/Principal Findings
A questionnaire was mailed to a randomly selected sample (n = 5000) residing in one of 4 areas of Japan. The BCQ was examined for responders who were bereaved more than 6 months and less than 10 years (n = 915). Non-specific psychological distress was assessed with the K6 screening scale. Multiple group confirmatory factor analysis supported a uni-dimensional factor structure and the invariance of parameters across gender and age. Cronbach''s alpha was sufficiently high (alpha = .75) to confirm internal consistency. Average Variance Extracted (0.39) was higher than the shared covariance (0.14) between BGQ and K6, suggesting discriminant validity.Conclusions
The results of this study support the reliability and validity of the BGQ in the Japanese population. Future studies should examine predictive validity by using structured interviews or more detailed scales for complicated grief. 相似文献104.
El-Shamy A Shoji I Kim SR Ide Y Imoto S Deng L Yoon S Fujisawa T Tani S Yano Y Seo Y Azuma T Hotta H 《PloS one》2012,7(2):e30513
Pegylated-interferon plus ribavirin (PEG-IFN/RBV) therapy is a current standard treatment for chronic hepatitis C. We previously reported that the viral sequence heterogeneity of part of NS5A, referred to as the IFN/RBV resistance-determining region (IRRDR), and a mutation at position 70 of the core protein of hepatitis C virus genotype 1b (HCV-1b) are significantly correlated with the outcome of PEG-IFN/RBV treatment. Here, we aimed to investigate the impact of viral genetic variations within the NS5A and core regions of other genotypes, HCV-2a and HCV-2b, on PEG-IFN/RBV treatment outcome. Pretreatment sequences of NS5A and core regions were analyzed in 112 patients infected with HCV-2a or HCV-2b, who were treated with PEG-IFN/RBV for 24 weeks and followed up for another 24 weeks. The results demonstrated that HCV-2a isolates with 4 or more mutations in IRRDR (IRRDR[2a]≥4) was significantly associated with rapid virological response at week 4 (RVR) and sustained virological response (SVR). Also, another region of NS5A that corresponds to part of the IFN sensitivity-determining region (ISDR) plus its carboxy-flanking region, which we referred to as ISDR/+C[2a], was significantly associated with SVR in patients infected with HCV-2a. Multivariate analysis revealed that IRRDR[2a]≥4 was the only independent predictive factor for SVR. As for HCV-2b infection, an N-terminal half of IRRDR having two or more mutations (IRRDR[2b]/N≥2) was significantly associated with RVR, but not with SVR. No significant correlation was observed between core protein polymorphism and PEG-IFN/RBV treatment outcome in HCV-2a or HCV-2b infection. CONCLUSION: The present results suggest that sequence heterogeneity of NS5A of HCV-2a (IRRDR[2a]≥4 and ISDR/+C[2a]), and that of HCV-2b (IRRDR[2b]/N≥2) to a lesser extent, is involved in determining the viral sensitivity to PEG-IFN/RBV therapy. 相似文献
105.
Meligy FY Shigemura K Behnsawy HM Fujisawa M Kawabata M Shirakawa T 《In vitro cellular & developmental biology. Animal》2012,48(4):203-215
The objective of the study is to evaluate efficiency of in vitro isolation and myogenic differentiation of mesenchymal stem
cells (MSCs) derived from adipose connective tissue (AD-MSCs), bone marrow (BM-MSCs), and skeletal muscle tissue (MC-MSCs).
MSCs were isolated from adipose connective tissue, bone marrow, and skeletal muscle tissue of two adult 6-wk-old rats. Cultured
MSCs were treated with 5-azacytidine (AZA) to induce myogenic differentiation. Isolated MSCs and differentiated cells were
evaluated by immunocytochemistry (ICC), fluorescence-activated cell sorting (FACS), PCR, and RT-PCR. AD-MSCs showed the highest
proliferation rate while BM-MSCs had the lowest one. In ICC, isolated MSCs had strong CD90- and CD44-positive expression and
negative expression of CD45, CD31, and CD34, while AZA-treated MSCs had strong positive desmin expression. In FACS analysis,
AD-MSCs had the highest percentage of CD90- and CD44-positive-expressing cells (99% and 96%) followed by BM-MSCs (97% and
94%) and MC-MSCs (92% and 91%).At 1 wk after incubation with AZA treatment, the peak of myogenin expression reached 93% in
differentiated MC-MSCs, 83.3% in BM-MSCs, and 77% in AD-MSCs. MSCs isolated from adipose connective tissue, bone marrow, and
skeletal muscle tissue have the same morphology and phenotype, but AD-MSCs were the most easily accessible and had the highest
rate of growth on cultivation and the highest percentage of stem cell marker expression. Moreover, although MC-MSCs showed
the highest rate of myogenic differentiation potential and expression of myoblast markers, AD-MSCs and BM-MSCs still can be
valuable alternatives. The differentiated myoblastic cells could be an available new choice for myoblastic auto-transplantation
in regeneration medicine. 相似文献
106.
E Napoli C Ross-Inta S Wong C Hung Y Fujisawa D Sakaguchi J Angelastro A Omanska-Klusek R Schoenfeld C Giulivi 《PloS one》2012,7(8):e42504
Etiology of aberrant social behavior consistently points to a strong polygenetic component involved in fundamental developmental pathways, with the potential of being enhanced by defects in bioenergetics. To this end, the occurrence of social deficits and mitochondrial outcomes were evaluated in conditional Pten (Phosphatase and tensin homolog) haplo-insufficient mice, in which only one allele was selectively knocked-out in neural tissues. Pten mutations have been linked to Alzheimer's disease and syndromic autism spectrum disorders, among others. By 4-6 weeks of age, Pten insufficiency resulted in the increase of several mitochondrial Complex activities (II-III, IV and V) not accompanied by increases in mitochondrial mass, consistent with an activation of the PI3K/Akt pathway, of which Pten is a negative modulator. At 8-13 weeks of age, Pten haplo-insufficient mice did not show significant behavioral abnormalities or changes in mitochondrial outcomes, but by 20-29 weeks, they displayed aberrant social behavior (social avoidance, failure to recognize familiar mouse, and repetitive self-grooming), macrocephaly, increased oxidative stress, decreased cytochrome c oxidase (CCO) activity (50%) and increased mtDNA deletions in cerebellum and hippocampus. Mitochondrial dysfunction was the result of a downregulation of p53-signaling pathway evaluated by lower protein expression of p21 (65% of controls) and the CCO chaperone SCO2 (47% of controls), two p53-downstream targets. This mechanism was confirmed in Pten-deficient striatal neurons and, HCT 116 cells with different p53 gene dosage. These results suggest a unique pathogenic mechanism of the Pten-p53 axis in mice with aberrant social behavior: loss of Pten (via p53) impairs mitochondrial function elicited by an early defective assembly of CCO and later enhanced by the accumulation of mtDNA deletions. Consistent with our results, (i) SCO2 deficiency and/or CCO activity defects have been reported in patients with learning disabilities including autism and (ii) mutated proteins in ASD have been found associated with p53-signaling pathways. 相似文献
107.
Kimura K Sakamoto Y Fujisawa N Uesugi S Aburai N Kawada M Ohba S Yamori T Tsuchiya E Koshino H 《Bioorganic & medicinal chemistry》2012,20(12):3887-3897
A bisabolane sesquiterpene endoperoxide compound, 3,6-epidioxy-1,10-bisaboladiene (EDBD), was isolated from edible wild plants grown in the northern area of Japan, Cacalia delphiniifolia and Cacalia hastata, using a mutant yeast (cdc2-1 rad9Δ). It showed cytotoxicity at IC(50) = 3.4 μM and induced apoptosis against the human promyelocytic leukemia cell line HL60 through a new stable rearrangement product (1) when in the presence of FeSO(4). This conversion mechanism is different from another sesquiterpene endoperoxide lactone compound, dihydroartemisinin (DHA), which is an anti-malarial drug. The cytotoxicity of EDBD decreased in the presence of the ferrous ion chelating drug deferoxamine mesylate (DFOM), and this suggested that the structural change of the drug caused by Fe(2+) may be responsible for its biological activities. EDBD induced apoptosis via phosphorylation of p38 mitogen-activated protein kinase (MAPK) in HL60 cells, and was detected by Western blot. EDBD resulted in an immediate increase in DCF fluorescence intensity in HL60 cells using DCFH-DA (2',7'-dichlorofluorescin diacetate) assay. The in vitro reaction of EDBD with FeSO(4) also increased DCF fluorescence intensity in a dose dependent manner. These results showed that the biological activity of EDBD involves an unstable carbon-centered radical intermediate. Furthermore, there was no similarity between the JFCR39 fingerprints of EDBD and DHA (correlation coefficient on COMPARE Analysis γ = 0.158). EDBD showed anti-tumor effects against a xenograft of Lox-IMVI cells in vivo. 相似文献
108.
109.
Shibata Y He LH Toda Y Kataoka Y Fujisawa N Miyazaki T Swain MV 《Journal of biomechanics》2008,41(16):3414-3418
The biomechanical stability of osseointegrated implants is of particular importance, especially the stability which is achieved from structural manipulation at the interface between the implant surface and the bone tissues. Nanoscale β-tricalcium phosphate-immobilized titanium was prepared by discharge into a physiological buffered saline solution. Compared with hydroxyapatite, it has been shown to be effective in generating a bone-like chemical structure on the surface by cooperative interaction between osteoblastic cells and the β-tricalcium phosphate. The present study, after cell cultivation, investigates the nanostructures and biomechanical property differences of a mineralized layer formed on two samples of nano-calcium phosphate-immobilized titanium. A scanning probe microscope study revealed that the mineralized tissue formed on the β-tricalcium phosphate samples after 1 week of cell culture showed significantly higher roughness, compared with hydroxyapatite samples. Nanoindentation micromechanical evaluation of the in vitro generated multilayered structures exhibited thicker bone-like mineralized layers on the β-tricalcium phosphate samples. A successful modification of titanium implants through the cooperative interaction between osteoblastic cells and nano β-tricalcium phosphate is anticipated. 相似文献
110.
Tomoko Tsuchida-Mayama Michiharu Nakano Yukiko Uehara Miho Sano Noriko Fujisawa Kiyotaka Okada Tatsuya Sakai 《Plant science》2008,174(6):626-633
The phototropic response in Arabidopsis thaliana is initiated by the blue-light photoreceptors, phototropin (phot)1 and phot2. A recent study has shown that one of the phototropic signal transducers, NPH3, is phosphorylated under dark conditions and dephosphorylated by blue-light irradiation. To further understand the function of phosphorylation and dephosphorylation of NPH3 during this phototropic response, we have mapped the phosphorylation sites of NPH3 in our current study. The NPH3 protein has at least three phosphorylation sites at serine residues, Ser212, Ser222, and Ser236, and these sites are dephosphorylated by blue-light irradiation. By immunoblotting analysis, these phosphorylation sites in phot1 mutants are not dephosphorylated following blue-light irradiation at both low and high fluence rates, even though such irradiations induce the phot2-dependent phototropic response in phot1. These results suggest that the dephosphorylated NPH3 is involved in the phot1-dependent phototropic response and is not essential for the phot2-dependent phototropic response. We generated two types of transgenic nph3 plants expressing a NPH3S212A/S222A/S232A/S236A protein and a NPH3Δ212–238 protein in which the phosphorylation region is deleted, and assessed the phototropic phenotype of these. Based upon our present findings, we discuss the role of dephosphorylated and phosphorylated NPH3 in mediating the phototropic response. 相似文献