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41.
Geon Ha Kim Seun Jeon Kiho Im Hunki Kwon Byung Hwa Lee Ga Young Kim Hana Jeong Noh Eul Han Sang Won Seo Hanna Cho Young Noh Sang Eon Park Hojeong Kim Jung Won Hwang Cindy W. Yoon Hee Jin Kim Byoung Seok Ye Ju Hee Chin Jung-Hyun Kim Mee Kyung Suh Jong Min Lee Sung Tae Kim Mun-Taek Choi Mun Sang Kim Kenneth M Heilman Jee Hyang Jeong Duk L. Na 《PloS one》2015,10(4)
The purpose of this study was to investigate if multi-domain cognitive training, especially robot-assisted training, alters cortical thickness in the brains of elderly participants. A controlled trial was conducted with 85 volunteers without cognitive impairment who were 60 years old or older. Participants were first randomized into two groups. One group consisted of 48 participants who would receive cognitive training and 37 who would not receive training. The cognitive training group was randomly divided into two groups, 24 who received traditional cognitive training and 24 who received robot-assisted cognitive training. The training for both groups consisted of daily 90-min-session, five days a week for a total of 12 weeks. The primary outcome was the changes in cortical thickness. When compared to the control group, both groups who underwent cognitive training demonstrated attenuation of age related cortical thinning in the frontotemporal association cortices. When the robot and the traditional interventions were directly compared, the robot group showed less cortical thinning in the anterior cingulate cortices. Our results suggest that cognitive training can mitigate age-associated structural brain changes in the elderly.
Trial Registration
ClnicalTrials.gov NCT01596205 相似文献42.
Neonatal transplantation tolerance to the products of theH-2
b
complex was induced in B10.A (H-2
a
) mice. On the basis of the survival of skin allografts it was found that antigens determined by theD region of theH-2
b
complex (of the B10.A(2R) strain) were most easily overcome and that tolerance to the products of theD end of theH-2 complex (of the B10.A(4R) strain) was also easy to induce. The antigens produced by theK end ofH-2 (of the B10.A(5R) and B10.A(3R) strains) represented a stronger incompatibility barrier and a difference in the entireH-2
b
complex caused strongest resistance to tolerance induction. When tolerance to the products of the entireH-2
b
complex was induced in newborn B10.A mice, and the neonatally treated animals were grafted simultaneously with five different grafts, those disparate at theK end ofH-2 and in the entireH-2 region were rejected in some animals, while the grafts disparate at theD end of H-2 remained intact in the same mice. No dependence on theI-J subregion was observed in this system. Furthermore, tolerance was more easily inducible in male than in female B10.A mice. 相似文献
43.
Yoo Jung Park Ha Young Lee Young Su Jung Joon Seong Park Jae Sam Hwang Yoe-Sik Bae 《BMB reports》2015,48(8):479-484
In this study, we report that one of the antimicrobial peptides scolopendrasin VII, derived from Scolopendra subspinipes mutilans, stimulates actin polymerization and the subsequent chemotactic migration of macrophages through the activation of ERK and protein kinase B (Akt) activity. The scolopendrasin VII-induced chemotactic migration of macrophages is inhibited by the formyl peptide receptor 1 (FPR1) antagonist cyclosporine H. We also found that scolopendrasin VII stimulate the chemotactic migration of FPR1-transfected RBL-2H3 cells, but not that of vector-transfected cells; moreover, scolopendrasin VII directly binds to FPR1. Our findings therefore suggest that the antimicrobial peptide scolopendrasin VII, derived from Scolopendra subspinipes mutilans, stimulates macrophages, resulting in chemotactic migration via FPR1 signaling, and the peptide can be useful in the study of FPR1-related biological responses. [BMB Reports 2015; 48(8): 479-484] 相似文献
44.
The enzyme HemK (or PrmC) is one of the first identified methyltransferases that modify glutamine. It methylates the highly conserved GGQ motif in class I release factors (RF1 and RF2) in Escherichia coli. HemK from Thermotoga maritima was over-expressed and crystallized in the presence of S-adenosylmethionine at 296 K using ammonium sulfate as the precipitant. X-ray diffraction data were collected to 2.5 A resolution from a native crystal. The crystal is orthorhombic, belonging to the space group I222 (or I2(1)2(1)2(1)), with unit-cell parameters of a = 104.24, b = 118.73, and c = 146.62 A. Two (or three) monomers of recombinant HemK are likely to be present in the crystallographic asymmetric unit, giving a V(M) of 3.62 A3 Da(-1) (or 2.41 A3 Da(-1)), with a solvent content of 62.7% (or 44.0%). 相似文献
45.
Jaeyoon Kim Yoon Sup Choi Seyoung Lim Kyungmoo Yea Jong Hyuk Yoon Dong‐Jae Jun Sang Hoon Ha Jung‐Wook Kim Jae Ho Kim Pann‐Ghill Suh Sung Ho Ryu Taehoon G. Lee 《Proteomics》2010,10(3):394-405
Adipogenesis is a complex process that is accompanied by a number of molecular events. In this study, a proteomic approach was adopted to identify secretory factors associated with adipogenesis. A label‐free shotgun proteomic strategy was implemented to analyze proteins secreted by human adipose stromal vascular fraction cells and differentiated adipocytes. A total of 474 proteins were finally identified and classified according to quantitative changes and statistical significances. Briefly, 177 proteins were significantly upregulated during adipogenesis (Class I), whereas 60 proteins were significantly downregulated (Class II). Changes in the expressions of several proteins were confirmed by quantitative RT‐PCR and immunoblotting. One obvious finding based on proteomic data was that the amounts of several extracellular modulators of Wnt and transforming growth factor‐β (TGF‐β) signaling changed during adipogenesis. The expressions of secreted frizzled‐related proteins, dickkopf‐related proteins, and latent TGF‐β‐binding proteins were found to be altered during adipogenesis, which suggests that they participate in the fine regulation of Wnt and TGF‐β signaling. This study provides useful tools and important clues regarding the roles of secretory factors during adipogenic differentiation, and provides information related to obesity and obesity‐related metabolic diseases. 相似文献
46.
Jehun Choi Sung Jin Bae Young Mi Ha Jae Kyung No Eun Kyeong Lee Jun Sik Lee Suhee Song Hyojin Lee Hongsuk Suh Byung Pal Yu Hae Young Chung 《Bioorganic & medicinal chemistry letters》2010,20(16):4882-4884
In searching for new agents with a depigmenting effect, we synthesized a derivative of resveratrol, 5-(6-hydroxy-2-naphthyl)-1,2,3-benzenetriol (5HNB) with a potent tyrosinase inhibitory activity. 5HNB inhibited mushroom tyrosinase with an IC50 value of 2.95 μM, which is more potent than the well-known anti-tyrosinase activity of kojic acid (IC50 = 38.24). The results of the enzymatic inhibition kinetics by Lineweaver–Burk analysis indicated 5HNB inhibits tyrosinase non-competitively when l-tyrosine was used as the substrate. Based on the strong inhibitory action of 5HNB, it is expected that 5HNB can suppress melanin production in which tyrosinase plays the essential role. Our expectation was confirmed by the experimentations with B16 melanoma cells in which 5HNB inhibited melanin production. We propose that 5HNB might have skin-whitening effects as well as therapeutic potential for treating skin pigmentation disorders. 相似文献
47.
48.
Staphylococcus aureus Lpl protein triggers human host cell invasion via activation of Hsp90 receptor
Paula M. Tribelli Arif Luqman Minh‐Thu Nguyen Johannes Madlung Sook‐Ha Fan Boris Macek Peter Sass Katharina Bitschar Birgit Schittek Dorothee Kretschmer Friedrich Gtz 《Cellular microbiology》2020,22(1)
Staphylococcus aureus is a facultative intracellular pathogen. Recently, it has been shown that the protein part of the lipoprotein‐like lipoproteins (Lpls), encoded by the lpl cluster comprising of 10 lpls paralogue genes, increases pathogenicity, delays the G2/M phase transition, and also triggers host cell invasion. Here, we show that a recombinant Lpl1 protein without the lipid moiety binds directly to the isoforms of the human heat shock proteins Hsp90α and Hsp90ß. Synthetic peptides covering the Lpl1 sequence caused a twofold to fivefold increase of S. aureus invasion in HaCaT cells. Antibodies against Hsp90 decrease S. aureus invasion in HaCaT cells and in primary human keratinocytes. Additionally, inhibition of ATPase function of Hsp90 or silencing Hsp90α expression by siRNA also decreased the S. aureus invasion in HaCaT cells. Although the Hsp90ß is constitutively expressed, the Hsp90α isoform is heat‐inducible and appears to play a major role in Lpl1 interaction. Pre‐incubation of HaCaT cells at 39°C increased both the Hsp90α expression and S. aureus invasion. Lpl1‐Hsp90 interaction induces F‐actin formation, thus, triggering an endocytosis‐like internalisation. Here, we uncovered a new host cell invasion principle on the basis of Lpl‐Hsp90 interaction. 相似文献
49.
Jatropha curcas L. is a small, woody tree of the Euphorbiaceae family. This plant can grow on marginal land in the tropical and subtropical regions and produces seeds containing up to 30% oil. Several Asian countries have selected Jatropha for large scale planting as a biodiesel feedstock. Nevertheless, Jatropha also possesses several undesirable traits that may limit its wide adoption. An improved understanding of plant development and the regulation of fatty acid (FA) and triacylglyceride biosynthesis in Jatropha is particularly facilitative for the development of elite crops. Here, we show that a tobacco rattle virus (TRV) vector can trigger virus-induced gene silencing (VIGS) in Jatropha. Our optimized method produced robust and reliable gene silencing in plants agroinoculated with recombinant TRV harbouring Jatropha gene sequences. We used VIGS to investigate possible functions of 13 Jatropha genes of several functional categories, including FA biosynthesis, developmental regulation and toxin biosynthesis, etc. Based on the effects of VIGS on the FA composition of newly emerged leaves, we determined the function of several genes implicated in FA biosynthesis. Moreover, VIGS was able to discriminate independent functions of related gene family members. Our results show that VIGS can be used for high-throughput screening of Jatropha genes whose functions can be assayed in leaves. 相似文献
50.
A fundamental question that applies to all organisms is how barrier epithelia efficiently manage continuous contact with microorganisms. Here, we show that in Drosophila an extracellular immune-regulated catalase (IRC) mediates a key host defense system that is needed during host-microbe interaction in the gastrointestinal tract. Strikingly, adult flies with severely reduced IRC expression show high mortality rates even after simple ingestion of microbe-contaminated foods. However, despite the central role that the NF-kappaB pathway plays in eliciting antimicrobial responses, NF-kappaB pathway mutant flies are totally resistant to such infections. These results imply that homeostasis of redox balance by IRC is one of the most critical factors affecting host survival during continuous host-microbe interaction in the gastrointestinal tract. 相似文献