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31.
A series of 1-substituted-3-(6-methylpyridin-2-yl)-4-([1,2,4]triazolo[1,5-a]pyridin-6-yl)pyrazoles 14a-ae, 16a, 16b, and 21a-c has been prepared and evaluated for their ALK5 inhibitory activity in an enzyme assay and in a cell-based luciferase reporter assay. The 4-([1,2,4]triazolo[1,5-a]pyridin-6-yl)-N-(4-methoxyphenyl)-3-(6-methylpyridin-2-yl)-1H-pyrazole-1-carbothioamide (14n) inhibited ALK5 phosphorylation with IC(50) value of 0.57 nM and showed 94% inhibition at 100 nM in a luciferase reporter assay using HaCaT cells permanently transfected with p3TP-luc reporter construct.  相似文献   
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Poly (β-l-malic acid) (PMLA) is a water-soluble polyester with many attractive properties in chemical industry and medicine development. However, the low titer of PMLA in the available producer strains limits further industrialization efforts and restricts its many potential applications. In order to solve this problem, a new strain with the distinguished high productivity of PMLA was isolated from fresh plants samples. It was characterized as the candidate of Aureobasidium pullulans based on the morphology and phylogenetic analyses of the internal transcribed spacer sequences. After the optimization of culture conditions, the highest PMLA concentration (62.27 g l−1) could be achieved in the shake flask scale. In addition, the contribution of the carbon flux to exopolysaccharide (EPS) and PMLA could be regulated by the addition of CaCO3 in the medium. This high-level fermentation process was further scaled up in the 10 l benchtop fermentor with a high PMLA concentration (57.2 g l−1) and productivity (0.35 g l−1 h−1), which are the highest level in all the literature. Finally, the suitable acid hydrolysis conditions of PMLA were also investigated with regard to the production of l-malic acid, and the kinetics of PMLA acid hydrolysis was modeled to simulate the whole degradation process. The present work paved the road to produce this multifunctional biomaterial (PMLA) at industrial scale and promised one alternative method to produce l-malic acid in the future.  相似文献   
35.
Vascular smooth muscle cell (VSMC) proliferation is a hallmark of neointimal hyperplasia (NIH) in atherosclerosis and restenosis post-balloon angioplasty and stent insertion. Although numerous cytotoxic and cytostatic therapeutics have been developed to reduce NIH, it is improbable that a multifactorial disease can be successfully treated by focusing on a preconceived hypothesis. We, therefore, aimed to identify key molecules involved in NIH via a hypothesis-free approach. We analyzed four datasets (GSE28829, GSE43292, GSE100927, and GSE120521), evaluated differentially expressed genes (DEGs) in wire-injured femoral arteries of mice, and determined their association with VSMC proliferation in vitro. Moreover, we performed RNA sequencing on platelet-derived growth factor (PDGF)-stimulated human VSMCs (hVSMCs) post-phosphoenolpyruvate carboxykinase 2 (PCK2) knockdown and investigated pathways associated with PCK2. Finally, we assessed NIH formation in Pck2 knockout (KO) mice by wire injury and identified PCK2 expression in human femoral artery atheroma. Among six DEGs, only PCK2 and RGS1 showed identical expression patterns between wire-injured femoral arteries of mice and gene expression datasets. PDGF-induced VSMC proliferation was attenuated when hVSMCs were transfected with PCK2 siRNA. RNA sequencing of PCK2 siRNA-treated hVSMCs revealed the involvement of the Akt-FoxO-PCK2 pathway in VSMC proliferation via Akt2, Akt3, FoxO1, and FoxO3. Additionally, NIH was attenuated in the wire-injured femoral artery of Pck2-KO mice and PCK2 was expressed in human femoral atheroma. PCK2 regulates VSMC proliferation in response to vascular injury via the Akt-FoxO-PCK2 pathway. Targeting PCK2, a downstream signaling mediator of VSMC proliferation, may be a novel therapeutic approach to modulate VSMC proliferation in atherosclerosis.  相似文献   
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The anti-diabetic potential of Petalonia binghamiae extract (PBE) was evaluated in vivo. Dietary administration of PBE to streptozotocin (STZ)-induced diabetic mice significantly lowered blood glucose levels and improved glucose tolerance. The mode of action by which PBE attenuated diabetes was investigated in vitro using 3T3-L1 cells. PBE treatment stimulated 3T3-L1 adipocyte differentiation as evidenced by increased triglyceride accumulation. At the molecular level, peroxisome proliferator-activated receptor γ (PPARγ) and terminal marker protein aP2, as well as the mRNA of GLUT4 were up-regulated by PBE. In mature adipocytes, PBE significantly stimulated the uptake of glucose and the expression of insulin receptor substrate-1 (IRS-1). Furthermore, PBE increased PPARγ luciferase reporter gene activity in COS-1 cells. Taken together, these results suggest that the in vivo anti-diabetic effect of PBE is mediated by both insulin-like and insulin-sensitizing actions in adipocytes.  相似文献   
38.
Chromosomal translocations are rare in myelodysplastic syndrome (MDS) and their impact on overall survival (OS) and response to hypomethylating agents (HMA) is unknown. The prognostic impact of the revised International Prognostic Scoring System (IPSS-R) and for chromosomal translocations was assessed in 751 patients from the Korea MDS Registry. IPSS-R effectively discriminated patients according to leukaemia evolution risk and OS. We identified 40 patients (5.3%) carrying translocations, 30 (75%) of whom also fulfilled complex karyotype criteria. Translocation presence was associated with a shorter OS (median, 12.0 versus 79.7 months, P < 0.01). Multivariate analysis demonstrated that translocations (hazard ratio [HR] 1.64 [1.06–2.63]; P = 0.03) as well as age, sex, IPSS-R, and CK were independent predictors of OS. In the IPSS-R high and very high risk subgroup (n = 260), translocations remained independently associated with OS (HR 1.68 [1.06–2.69], P = 0.03) whereas HMA treatment was not associated with improved survival (median OS, 20.9 versus 21.2 months, P = 0.43). However, translocation carriers exhibited enhanced survival following HMA treatment (median 2.1 versus 12.4 months, P = 0.03). Our data suggest that chromosomal translocation is an independent predictor of adverse outcome and has an additional prognostic value in discriminating patients with MDS having higher risk IPSS-R who could benefit from HMA treatment.  相似文献   
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Background

We presented the photoacoustic imaging (PAI) tool and to evaluate whether microcalcifications in breast tissue can be detected on photoacoustic (PA) images.

Methods

We collected 21 cores containing microcalcifications (n = 11, microcalcification group) and none (n = 10, control group) in stereotactic or ultrasound (US) guided 8-gauge vacuum-assisted biopsies. Photoacoustic (PA) images were acquired through ex vivo experiments by transmitting laser pulses with two different wavelengths (700 nm and 800 nm). The presence of microcalcifications in PA images were blindly assessed by two radiologists and compared with specimen mammography. A ratio of the signal amplitude occurring at 700 nm to that occurring at 800 nm was calculated for each PA focus and was called the PAI ratio.

Results

Based on the change of PA signal amplitude between 700 nm and 800 nm, 10 out of 11 specimens containing microcalcifications and 8 out of 10 specimens without calcifications were correctly identified on blind review; the sensitivity, specificity, accuracy, positive predictive and negative predictive values of our blind review were 90.91%, 80.0%, 85.71%, 83.33% and 88.89%. The PAI ratio in the microcalcification group was significantly higher than that in the control group (the median PAI ratio, 2.46 versus 1.11, respectively, P = .001). On subgroup analysis in the microcalcification group, neither malignant diagnosis nor the number or size of calcification-foci was proven to contribute to PAI ratios.

Conclusion

Breast microcalcifications generated distinguishable PA signals unlike breast tissue without calcifications. So, PAI, a non-ionizing and non-invasive hybrid imaging technique, can be an alternative in overcoming the limitations of conventional US imaging.  相似文献   
40.
Jin HT  Jeong YH  Park HJ  Ha SJ 《BMB reports》2011,44(4):217-231
T cell exhaustion develops under conditions of antigen-persistence caused by infection with various chronic pathogens, such as human immunodeficiency virus (HIV) and mycobacterium tuberculosis (TB), or by the development of cancer. T cell exhaustion is characterized by stepwise and progressive loss of T cell function, which is probably the main reason for the failed immunological control of chronic pathogens and cancers. Recent observations have detailed some of the intrinsic and extrinsic factors that influence the severity of T cell exhaustion. Duration and magnitude of antigenic activation of T cells might be associated with up-regulation of inhibitory receptors, which is a major intrinsic factor of T cell exhaustion. Extrinsic factors might include the production of suppressive cytokines, T cell priming by either non-professional antigen-presenting cells (APCs) or tolerogenic dendritic cells (DCs), and alteration of regulatory T (Treg) cells. Further investigation of the cellular and molecular processes behind the development of T cell exhaustion can reveal therapeutic targets and strategies for the treatment of chronic infections and cancers. Here, we report the properties and the mechanisms of T cell exhaustion in a chronic environment.  相似文献   
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