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Photoacoustic microscopy (PAM) is a noninvasive imaging technique and is excellent to study structural and functional changes in the microcirculation. In this work, a lipopolysaccharide (LPS)‐induced inflammation model in mice is noninvasively evaluated by PAM. PAM is used to image the microvascular structural changes in mice for 8 hours after the LPS with different concentrations is applied. Quantitative analysis of five vessel parameters is conducted, which shows that the rate of reduction in microvasculature is highly dependent on the applied LPS concentrations. For low‐concentration LPS, changes in the microvasculature are not obvious over the observation period, whereas for high‐concentration LPS, quick and marked reduction in the microvasculature is observed. In addition, changes in capillaries are more significant than those in relatively large vessels. The results show that PAM is able to evaluate the inflammation mouse model by studying structural (and potentially functional) changes in the microcirculation. Furthermore, PAM may have potential for early intervention and treatment plan optimization of sepsis by monitoring the microcirculation and inflammatory response. 相似文献
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Sung Won Lee Hyun Jung Park Seo Hyun Kim Sooyong Shin Kyung Hee Kim Sang Jae Park 《Animal cells and systems.》2019,23(3):184-191
We recently demonstrated that the polysaccharide component of the Korean medicinal herb Angelica gigas (immuno-stimulatory fraction of A. gigas; ISAg) induces anticancer effects in mice by activating natural killer (NK) and natural killer T (NKT) cells. However, it is unclear whether the use of ISAg in vivo can affect the differentiation of conventional T cells. Here, we investigated the effects of ISAg on the activation of conventional CD4+ and CD8+ T cells. We found that the administration of ISAg induced the polarization of CD4+ T cells toward the acquisition of the Th1 phenotype in vivo. Additionally, in mice treated with ISAg, CD8+ T cells produced more IFNγ than in control mice treated with PBS. Moreover, treatment with ISAg activated CD4+ and CD8+ T cells as well as NK and NKT cells, resulting in the secretion of Th1-type cytokines in a toll-like receptor 4 (TLR4)-dependent manner, implying that TLR4 is critical for an optimal Th1 response. Interestingly, ISAg treatment increased the number of Foxp3+ Treg cells, but not of Th2 cells, compared to control mice treated with PBS, indicating that ISAg possesses an immunomodulatory capacity that can control adaptive immune responses. Taken together, our results indicate that ISAg possesses a Th1-enhancing activity that could be used to treat Th2-mediated allergic immune diseases such as atopic dermatitis. 相似文献
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Wonjong Yu Min-kyu Yang Dong Jun Sung Tae Jun Park Myungchul Kim Eustache Ntigura Sung Hea Kim Bokyung Kim Sang Woong Park Young Min Bae 《Biochemistry and Biophysics Reports》2022
As the geriatric population and life expectancy increase, the interest in preventing geriatric diseases, such as sarcopenia, is increasing. However, the causes of sarcopenia are unclear, and current diagnostic methods for sarcopenia are unreliable. We hypothesized that the changes in the expression of certain miRNAs may be associated with the pathophysiology of sarcopenia. Herein, we analyzed the miRNA expression profiles in the blood of young (3-months-old) healthy rats, old sarcopenic (17-months-old) rats, and age-matched (17-months-old) control rats. The changes in miRNA expression levels were analyzed using Bowtie 2 software. A total of 523 miRNAs were detected in the rat serum. Using scatter plots and clustering heatmap data, we found 130 miRNAs that were differentially expressed in sarcopenic rats (>2-fold change) compared to the expression in young healthy and age-matched control rats. With a threshold of >5-fold change, we identified 14 upregulated miRNAs, including rno-miR-133b-3p, rno-miR-133a-3p, rno-miR-133c, rno-miR-208a-3p, and rno-miR434-5p among others in the serum of sarcopenic rats. A protein network map based on these 14 miRNAs identified the genes involved in skeletal muscle differentiation, among which Notch1, Egr2, and Myocd represented major nodes. The data obtained in this study are potentially useful for the early diagnosis of sarcopenia and for the identification of novel therapeutic targets for the treatment and/or prevention of sarcopenia. 相似文献
189.
A hybrid model for erythrocyte membrane: a single unit of protein network coupled with lipid bilayer
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To investigate the nanomechanics of the erythrocyte membrane we developed a hybrid model that couples the actin-spectrin network to the lipid bilayer. This model features a Fourier space Brownian dynamics model of the bilayer, a Brownian dynamics model of the actin protofilament, and a modified wormlike-chain model of the spectrin (including a cable-dynamics model to predict the oscillation in tension). This model enables us to predict the nanomechanics of single or multiple units of the protein network, the lipid bilayer, and the effect of their interactions. The present work is focused on the attitude of the actin protofilament at the equilibrium states coupled with the elevations of the lipid bilayer through their primary linkage at the suspension complex in deformations. Two different actin-spectrin junctions are considered at the junctional complex. With a point-attachment junction, large pitch angles and bifurcation of yaw angles are predicted. Thermal fluctuations at bifurcation may lead to mode-switching, which may affect the network and the physiological performance of the membrane. In contrast, with a wrap-around junction, pitch angles remain small, and the occurrence of bifurcation is greatly reduced. These simulations suggest the importance of three-dimensional molecular junctions and the lipid bilayer/protein network coupling on cell membrane mechanics. 相似文献
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Kim SY Kim JY Kim SH Bae HJ Yi H Yoon SH Koo BS Kwon M Cho JY Lee CE Hong S 《FEBS letters》2007,581(5):865-871
The effect of surfactin on the proliferation of LoVo cells, a human colon carcinoma cell line, was examined. Surfactin strongly blocked the proliferation of LoVo cells by inducing pro-apoptotic activity and arresting the cell cycle, according to several lines of evidence on DNA fragmentation, Annexin V staining, and altered levels of poly (ADP-ribose) polymerase, caspase-3, p21(WAF1/Cip1), p53, CDK2 and cyclin E. The anti-proliferative activity of surfactin was mediated by inhibiting extracellular-related protein kinase and phosphoinositide 3-kinase/Akt activation, as assessed by phosphorylation levels. Therefore, our data suggest that surfactin may have anti-cancer properties as a result of its ability to downregulate the cell cycle and suppress its survival. 相似文献