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71.
Hahn  Kyu Ri  Kim  Woosuk  Jung  Hyo Young  Kwon  Hyun Jung  Kim  Dae Won  Hwang  In Koo  Yoon  Yeo Sung 《Neurochemical research》2022,47(4):1073-1082
Neurochemical Research - Cuprizone is commonly used to induce neuronal demyelination in mice. In the present study, we compared the cuprizone-induced demyelination in the corpus callosum and...  相似文献   
72.
The record efficiency of the state‐of‐the‐art polymer solar cells (PSCs) is rapidly increasing, due to the discovery of high‐performance photoactive donor and acceptor materials. However, strong questions remain as to whether such high‐efficiency PSCs can be produced by scalable processes. This paper reports a high power conversion efficiency (PCE) of 13.5% achieved with single‐junction ternary PSCs based on PTB7‐Th, PC71BM, and COi8DFIC fabricated by slot‐die coating, which shows the highest PCE ever reported in PSCs fabricated by a scalable process. To understand the origin of the high performance of the slot‐die coated device, slot‐die coated photoactive films and devices are systematically investigated. These results indicate that the good performance of the slot‐die PSCs can be due to a favorable molecule‐structure and film‐morphology change by introducing 1,8‐diiodooctane and heat treatment, which can lead to improved charge transport with reduced carrier recombination. The optimized condition is then used for the fabrication of large‐area modules and also for roll‐to‐roll fabrication. The slot‐die coated module with 30 cm2 active‐area and roll‐to‐roll produced flexible PSC has shown 8.6% and 9.6%, respectively. These efficiencies are the highest in each category and demonstrate the strong potential of the slot‐die coated ternary system for commercial applications.  相似文献   
73.
The precise mechanism of TGFβ1 signaling in the progression of non-alcoholic steatohepatitis (NASH) has remained unclear. In particular, a potential regulatory mechanism by which PKCδ affects profibrogenic gene expression had never been explored. In this study, therefore, the role of PKCδ in TGFβ1 mediated α-SMA expression was investigated using NASH model mice. In preparation of the NASH model, male C57BL6/J mice were fed a methionine-choline-deficient (MCD) diet for 3 weeks, after which time they were intraperitoneally injected with lipopolysaccharide (LPS). In addition, Tlr4Lps-d (CH3/HeJ) mice were used to demonstrate the TGFβ1 signaling’s dependency on TLR4 induction. Liver histology and hepatic hepatitis markers were investigated, and hepatic gene expression levels were determined by real-time PCR. Acute liver injury by LPS injection specifically elevated not only α-SMA expression but also phospho-PKCδ in this model. In contrast, Tlr4Lps-d (CH3/HeJ) and blockade of TGFβ1 receptor by SB431542 resulted in a significant reduction of PKCδ activation and α-SMA expression. Moreover, the TGFβ1-induced α-SMA production was significantly reduced by a specific PKCδ inhibitor. These findings suggested that PKCδ plays a critical role in TGFβ1-induced α-SMA production in a NASH model. Thus, this was the first demonstration of the involvement of PKCδ in the regulation of α-SMA expression in NASH liver tissues, and the impaired induction of PKCδ phosphorylation by LPS in a steatohepatitis condition. Interestingly, treatment by PKCδ inhibitor caused dramatic reduction of myofibroblast activation, indicating that PKCδ represents a promising target for treating NASH.  相似文献   
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Objective

This study was designed to investigate the revised and short version of the smartphone addiction scale and the proof of its validity in adolescents. In addition, it suggested cutting off the values by gender in order to determine smartphone addiction and elaborate the characteristics of smartphone usage in adolescents.

Method

A set of questionnaires were provided to a total of 540 selected participants from April to May of 2013. The participants consisted of 343 boys and 197 girls, and their average age was 14.5 years old. The content validity was performed on a selection of shortened items, while an internal-consistency test was conducted for the verification of its reliability. The concurrent validity was confirmed using SAS, SAPS and KS-scale. Receiver operating characteristics analysis was conducted to suggest cut-off.

Results

The 10 final questions were selected using content validity. The internal consistency and concurrent validity of SAS were verified with a Cronbach''s alpha of 0.911. The SAS-SV was significantly correlated with the SAS, SAPS and KS-scale. The SAS-SV scores of gender (p<.001) and self-evaluation of smartphone addiction (p<.001) showed significant difference. The ROC analysis results showed an area under a curve (AUC) value of 0.963(0.888–1.000), a cut-off value of 31, sensitivity value of 0.867 and specificity value of 0.893 in boys while an AUC value of 0.947(0.887–1.000), a cut-off value of 33, sensitivity value of 0.875, and a specificity value of 0.886 in girls.

Conclusions

The SAS-SV showed good reliability and validity for the assessment of smartphone addiction. The smartphone addiction scale short version, which was developed and validated in this study, could be used efficiently for the evaluation of smartphone addiction in community and research areas.  相似文献   
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3-Oxoacid CoA-transferase, which catalyses the first committed step in the oxidation of ketone bodies, is uniquely regulated in developing rat brain. Changes in 3-oxoacid CoA-transferase activity in rat brain during the postnatal period are due to changes in the relative rate of synthesis of the enzyme. To study the regulation of this enzyme, we identified, with a specific polyclonal rabbit anti-(rat 3-oxoacid CoA-transferase), two positive cDNA clones (approx. 800 bp) in a lambda gtll expression library, constructed from poly(A)+ RNA from brains of 12-day-old rats. One of these clones (lambda CoA3) was subcloned into M13mp18 and subjected to further characterization. Labelled single-stranded probes prepared by primer extension of the M13mp18 recombinant hybridized to a 3.6 kb mRNA. Rat brain mRNA enriched by polysome immunoadsorption for a single protein of size 60 kDa which corresponds to the precursor form of 3-oxoacid CoA-transferase was also found to be similarly enriched for the hybridizable 3.6 kb mRNA complementary to lambda CoA3. Affinity-selected antibody to the lambda CoA3 fusion protein inhibited 3-oxoacid CoA-transferase activity present in rat brain mitochondrial extracts. The 3.6 kb mRNA for 3-oxoacid CoA-transferase was present in relative abundance in rat kidney and heart, to a lesser extent in suckling brain and mammary gland and negligible in the liver. The specific mRNA was also found to be 3-fold more abundant in the brain from 12-day-old rats as compared with 18-day-old foetuses and adult rats, corresponding to the enzyme activity and relative rate of synthesis profile during development. These data suggest that 3-oxoacid CoA-transferase enzyme activity is regulated at a pretranslational level.  相似文献   
79.
In the model plant Arabidopsis thaliana, four Dicer‐like proteins (DCL1–4) mediate the production of various classes of small RNAs (sRNAs). Among these four proteins, DCL4 is by far the most versatile RNaseIII‐like enzyme, and previously identified dcl4 missense alleles were shown to uncouple the production of the various classes of DCL4‐dependent sRNAs. Yet little is known about the molecular mechanism behind this uncoupling. Here, by studying the subcellular localization, interactome and binding to the sRNA precursors of three distinct dcl4 missense alleles, we simultaneously highlight the absolute requirement of a specific residue in the helicase domain for the efficient production of all DCL4‐dependent sRNAs, and identify, within the PAZ domain, an important determinant of DCL4 versatility that is mandatory for the efficient processing of intramolecular fold‐back double‐stranded RNA (dsRNA) precursors, but that is dispensable for the production of small interfering RNAs (siRNAs) from RDR‐dependent dsRNA susbtrates. This study not only provides insights into the DCL4 mode of action, but also delineates interesting tools to further study the complexity of RNA silencing pathways in plants, and possibly other organisms.  相似文献   
80.
As malfunction/absence of immune cells causes a variety of immunosuppressive disorders and chemical synthetic drugs for curing these diseases have many adverse effects, vigorous studies are being conducted. The Acanthopanax family has been used as traditional medicines for gastric ulcer, diabetes, etc. and culinary materials in East-South Asia. In this study, the immunostimulating properties of A. sessiliflorus were evaluated. A. sessiliflorus increased not only the splenocyte number but also immune-related cytokines such as TNF-α. However, it could not upregulate the expressions of IFN-γ and IL-2. A. sessiliflorus increased the swimming time, and comparison of organ weights relative to body weights for immune-related organs such as the spleen and thymus after a forced swim test showed that it could recover the spleen and thymus weights. It also increased the expression of TNF-α and slightly increased the concentration of IFN-γ but not IL-2. From the results, we concluded that as A. sessiliflorus has not only a host defense effect but also a stress-ameliorating property, further study it will be a promising material of immunostimulating material.  相似文献   
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