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41.
Liu Jingna Zang Huadong Xu Heshui Zhang Kai Jiang Ying Hu Yuegao Zeng Zhaohai 《Plant and Soil》2019,438(1-2):85-99
Plant and Soil - Moso bamboo (Phyllostachys edulis) invasions into adjacent forests are becoming increasingly common. Moso bamboo invasions affect litter quality, soil nutrients, and microbial... 相似文献
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Si Zhang Zhongnan Yin Fei-Fei Dai Hao Wang Meng-Jiao Zhou Ming-Hui Yang Shu-Feng Zhang Zhi-Feng Fu Ying-Wu Mei Ming-Xi Zang Lixiang Xue 《Journal of cellular physiology》2019,234(8):13252-13262
Although cardiac hypertrophy is widely recognized as a risk factor that leads to cardiac dysfunction and, ultimately, heart failure, the complex mechanisms underlying cardiac hypertrophy remain incompletely characterized. The nuclear receptor peroxisome proliferator-activated receptor δ (PPARδ) is involved in the regulation of cardiac lipid metabolism. Here, we describe a novel PPARδ-dependent molecular cascade involving microRNA-29a (miR-29a) and atrial natriuretic factor (ANF), which is reactivated in cardiac hypertrophy. In addition, we identify a novel role of miR-29a, in which it has a cardioprotective function in isoproterenol hydrochloride-induced cardiac hypertrophy by targeting PPARδ and downregulating ANF. Finally, we provide evidence that miR-29a reduces the isoproterenol hydrochloride-induced cardiac hypertrophy response, thereby underlining the potential clinical relevance of miR-29a in which it may serve as a potent therapeutic target for heart hypertrophy treatment. 相似文献
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Adenosine, a catabolite of ATP, displays a wide variety of effects in the heart including regulation of cardiac response to myocardial ischemia and reperfusion injury. Nonetheless, the precise mechanism of adenosine-induced cardioprotection is still elusive. Isolated Sprague-Dawley rat hearts underwent 30 min global ischemia and 120 min reperfusion using a Langendorff apparatus. Both adenosine and acetylcholine treatment recovered the post-reperfusion cardiac function associated with adenosine and muscarinic receptors activation. Simultaneous administration of adenosine and acetylcholine failed to exert any additive protective effect, suggesting a shared mechanism between the two. Our data further revealed a cross-talk between the adenosine and acetylcholine receptor signaling in reperfused rat hearts. Interestingly, the selective M(2) muscarinic acetylcholine receptor antagonist methoctramine significantly attenuated the cardioprotective effect of adenosine. In addition, treatment with adenosine upregulated the expression and the maximal binding capacity of muscarinic acetylcholine receptor, which were inhibited by the selective A(1) adenosine receptor antagonist 8-Cyclopentyl-1,3-dipropylxanthine (DPCPX) and the nitric oxide synthase inhibitor N(ω)-nitro-L-arginine methyl ester (L-NAME). These data suggested a possible functional coupling between the adenosine and muscarinic receptors behind the observed cardioprotection. Furthermore, nitric oxide was found involved in triggering the response to each of the two receptor agonist. In summary, there may be a cross-talk between the adenosine and muscarinic receptors in ischemic/reperfused myocardium with nitric oxide synthase might serve as the distal converging point. In addition, adenosine contributes to the invigorating effect of adenosine on muscarinic receptor thereby prompting to regulation of cardiac function. These findings argue for a potentially novel mechanism behind the adenosine-mediated cardioprotection. 相似文献
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Hao Yan Lin Tian Jun Yan Wei Sun Qi Liu Yan-Bo Zhang Xin-Ming Li Yu-Feng Zang Dai Zhang 《PloS one》2012,7(9)
Introduction
Current pathophysiological theories of schizophrenia highlight the role of altered brain functional and anatomical connectivity. The cognitive division of anterior cingulate cortex (ACC-cd) is a commonly reported abnormal brain region in schizophrenia for its importance in cognitive control process. The aim of this study was to investigate the functional and anatomical connectivity of ACC-cd and its cognitive and clinical manifestation significance in schizophrenia by using the resting-state functional magnetic resonance imaging (fMRI) and the diffusion tensor imaging (DTI).Methods
Thirty-three medicated schizophrenics and 30 well-matched health controls were recruited. Region-of-interest (ROI)-based resting-state functional connectivity analysis and Tract-Based Spatial Statistics (TBSS) were performed on 30 patients and 30 controls, and 24 patients and 29 controls, respectively. The Pearson correlation was performed between the imaging measures and the Stroop performance and scores of the Positive and Negative Syndrome Scale (PANSS), respectively.Results
Patients with schizophrenia showed significantly abnormal in the functional connectivity and its hemispheric asymmetry of the ACC-cd with multiple brain areas, e.g., decreased positive connectivity with the bilateral putamen and caudate, increased negative connectivity with the left posterior cingulated cortex (PCC), increased asymmetry of connectivity strength with the contralateral inferior frontal gyrus (IFG). The FA of the right anterior cingulum was significantly decreased in patients group (p = 0.014). The abnormal functional and structural connectivity of ACC-cd were correlated with Stroop performance and the severity of the symptoms in patients.Conclusions
Our results suggested that the abnormal connectivity of the ACC-cd might play a role in the cognitive impairment and clinical symptoms in schizophrenia. 相似文献48.
Shixiang Wang Kun Zhao Weijin Zang Qian Zhang Xinfeng Zhao Ming Zhao Xi He Qinshe Liu Weiyi Feng Xiaohui Zheng 《Analytical biochemistry》2014
A highly selective assay was developed for screening compounds that bind to the porcine recombinant β2-adrenoceptor (β2-AR) with affinity chromatography coupled to quadrupole time-of-flight mass spectrometry (Q-TOF–MS). The methodology involved selective screening with immobilized β2-AR, a highly accurate identification via Q-TOF–MS, and a functional evaluation of the screened compounds with a sensitive myograph system. Ferulic acid, hydroxysafflor yellow A (HSYA), and naringin were confirmed to be the bioactive compounds in Huoxue capsule that specifically bound to the β2-AR. These compounds produced a concentration-dependent relaxation of arteries that were contracted by treatment with phenylephrine, and the relaxation caused by these compounds was attenuated in the presence of ICI 118551, a type of β2-AR antagonist. Our data indicate that the use of an immobilized receptor is potentially an alternative method for the rapid screening of bioactive compounds in a complex matrix because of its high specificity. β2-AR affinity chromatography was valuable in focusing attention on the further investigation of ferulic acid, HSYA, and naringin as β2-AR agonists. 相似文献
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The bioavailability and fractionation of Cu reflect its deliverability in soil. Little research has investigated Cu supply to crops in soil under long-term rotation and fertilisation on the Loess Plateau. A field experiment was conducted in randomized complete block design to determine the bioavailability and distribution of Cu fractions in a Heilu soil (Calcaric Regosol) after 18 years of rotation and fertilisation. The experiment started in 1984, including five cropping systems (fallow control, alfalfa cropping, maize cropping, winter wheat cropping, and grain-legume rotation of pea/winter wheat/winter wheat + millet) and five fertiliser treatments (unfertilised control, N, P, N + P, and N + P + manure). Soil samples were collected in 2002 for chemical analysis. Available Cu was assessed by diethylene triamine pentaacetic acid (DTPA) extraction, and Cu was fractionated by sequential extraction. Results showed that DTPA-Cu was lower in cropping systems compared with fallow control. Application of fertilisers resulted in no remarkable changes in DTPA-Cu compared with unfertilised control. Correlation and path analyses revealed that soil pH and CaCO3 directly affected Cu bioavailability, whereas available P indirectly affected Cu bioavailability. The concentrations of Cu fractions (carbonate and Fe/Al oxides) in the plough layer were lower in cropping systems, while the values in the plough sole were higher under grain-legume rotation relative to fallow control. Manure with NP fertiliser increased Cu fractions bound to organic matter and minerals in the plough layer, and its effects in the plough sole varied with cropping systems. The direct sources (organic-matter-bound fraction and carbonate-bound fraction) of available Cu contributed much to Cu bioavailability. The mineral-bound fraction of Cu acted as an indicator of Cu supply potential in the soil. 相似文献
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