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Carthamus tinctorius L. (Compositae) is used in Chinese medicine to treat heart disease and inflammation. In our previous study, we found that C. tinctorius L. inhibited lipopolysaccharides (LPS)‐induced tumor necrosis factor‐alpha (TNF‐α) activation, JNK expression, and apoptosis in H9c2 cardiomyoblast cells. The present study was performed to investigate the protective effect of C. tinctorius extract (CTF) on LPS‐challenged H9c2 myocardioblast cell and to explore the possible underlying mechanism. Cell viability assay showed that LPS treatment decreased the cell viability of H9c2 cell, whereas CTF treatment reversed LPS cytotoxicity in a dose‐dependent manner, especially in the LPS + CTF 25 (μg/mL) group. LPS treatment‐induced apoptosis was determined by transferase‐mediated dUTP nick end labeling assay, and by Western blot. LPS‐induced apoptotic bodies were decreased following CTF treatment. Expression of TNF‐α, FAS‐L, FAS, FADD, caspase‐8, BID, and t‐BID was significantly increased in LPS‐treated H9c2 cells. In contrast, it was significantly suppressed by the administration of CTF extract. In addition, CTF treatment activates antiapoptotic proteins, Bcl‐2 and p‐Bad, and downregulates Bax, cytochrome‐c, caspase‐9, caspase‐3, and apoptosis‐inducing factor expression. Furthermore, CTF exerted cytoprotective effects by activating insulin‐like growth factor‐I (IGF‐I) signaling pathway leading to downregulation of the apoptotic proteins involved in FAS death receptor pathway. In addition, AG1024 and IGF‐I receptor (IGF‐IR) inhibitor and siRNA silencing reverses the effect of CTF implying that CTF functions through the IGF‐IR pathway to inhibit LPS‐induced H9c2 apoptosis. These results suggest that treatment with CTF extract prevented the LPS‐induced apoptotic response through IGF‐I pathway.  相似文献   
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The paper focused on an experimental study on the microstructural, mechanical, and wear characteristics of 15 wt.% alumina (Al2O3) particulates with an average particle size of 20 µm, reinforced in Al2014 alloy matrix composite as-cast and heat-treated samples. The metal matrix composite (MMC)samples were produced via a novel two-stage stir-casting technique. The fabricated composite samples were subjected to evaluate hardness, tensile strength, fatigue behavior and wear properties for both as cast and T6 heat-treated test samples. The Al2014 alloy and Al2014-15 wt.% Al2O3 MMCs were in solution for 1 h at a temperature of 525 °C, quenched instantly in cold water, and then artificially aged for 10 h at a temperature of 175 °C. SEM and X-ray diffraction analyses were used to investigate the microstructure and dispersion of the reinforced Al2O3 particles in the composite and the base alloy Al2014. The obtained results indicated that the hardness, tensile and fatigue strength and wear resistance increased when an amount of Al2O3 particles was added, compared to the as-cast Al2014 alloy and it was observed that after subjecting the same composite samples to heat treatment, there was further enhancement in the mechanical and wear properties in the Al2014 matrix alloy and Al2014-15 wt.% Al2O3 composite samples.  相似文献   
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In direct conflict with the concept of auditory brainstem nuclei as passive relay stations for behaviorally-relevant signals, recent studies have demonstrated plasticity of the auditory signal in the brainstem. In this paper we provide an overview of the forms of plasticity evidenced in subcortical auditory regions. We posit an integrative model of auditory plasticity, which argues for a continuous, online modulation of bottom-up signals via corticofugal pathways, based on an algorithm that anticipates and updates incoming stimulus regularities. We discuss the negative implications of plasticity in clinical dysfunction and propose novel methods of eliciting brainstem responses that could specify the biological nature of auditory processing deficits.  相似文献   
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Caffeine is a stimulant thought to activate the pleasure centre in the brain, commonly used in the general public for purposeful attempt to alter mood, and also commonly perceived to be a bladder irritant with associated urgency and frequency symptoms. Mental health diagnosis, such as depression, is also associated with overactive bladder. Taken together, it is plausible that women with overactive bladder symptoms along with comorbid mental health symptoms may also show higher caffeine intake but no data exist. This pilot study's purpose was to determine in women with overactive bladder, if those with a mental health diagnosis (we included anxiety, depression, post-traumatic stress disorder and bipolar diagnosis) consume a significantly higher amount of caffeine than those without any of these diagnoses. Secondary analysis was performed on data from women with overactive bladder recruited into a longitudinal parent study on beverage management. All parent study participants met criteria of urgency and voiding more than seven times per day. Each kept a detailed 3-day diary of beverage intake. From the total parent study pool of 61, we identified 14 women with a comorbid mental health diagnosis as described above and 47 without when interviewed at baseline. Women with mental health diagnosis demonstrated higher median baseline caffeine intake per day than their counterparts without mental health diagnosis: 240·2 mg (range: 72·3–576·0 mg) versus 174·3 mg (range: 0–567·6 mg), which was marginally significant ( p = · 053). Volume of caffeinated beverage intake did not differ significantly. In women with overactive bladder and comorbid mental health symptoms, higher caffeine intake may be a previously unrecognized link. Cause and effect is unknown between the three conditions of overactive bladder, mental health disorders and higher caffeine intake; but this initial data support the need for further research.  相似文献   
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