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Abstract-There is increasing evidence that all-trans retinoic acid (atRA) influences gene expression of components of renin-angiotensin system (RAS), which plays a pivotal role in the pathophysiology of essential hypertension. To further validate effects of atRA on the RAS and to assess the possibility that atRA affects the activity of angiotensin-converting enzyme 2 (ACE2), gene, and protein expression of ACE2 have been examined by real-time polymerase chain reaction and Western blot methods in spontaneously hypertensive rats (SHR) and Wistar-Kyoto (WKY) rats. Rats were treated with atRA (10 or 20 mg ⅐ kg Ϫ1 ⅐ day Ϫ1 ) or placebo given as daily intraperitoneal injection for 1 month. ACE2 expression was markedly decreased in placebo-treated SHR when compared with WKY rats. However, in atRA-treated SHR, a significant upregulation of ACE2 expression was observed in heart and kidney. In conclusion, chronic atRA treatment increases gene and protein expressions of ACE2, resulting in the reduction of blood pressure and the attenuation of myocardial damage in SHR, which suggests that atRA may be an attractive candidate for the potential prevention and treatment of human essential hypertension. Key Words:hypertension, essential Ⅲ angiotensin-converting enzyme Ⅲ renin-angiotensin system Ⅲ rats I t is well-recognized that essential hypertension is a genetically complex metabolic and cardiovascular disorder controlled by both genetic and environmental factors. 1 The ideal aim of modern antihypertensive therapy is not only a reduction of blood pressure but also the prevention or amelioration of its complications, such as myocardial remodeling at the molecular genetic level. 2,3 Research advances on the key transcription factors and nuclear hormone receptors provide insight into the development of novel transcriptionmodulating antihypertensive drugs, among which is all-trans retinoic acid (atRA), a biologically active metabolite of vitamin A. 2 atRA modulates gene transcription and exerts its other effects by binding the retinoic acid receptor (RAR) and retinoid X receptor (RXR) 4,5 and interfering with some key transcription factors such as the activated protein-1. 6,7 Studies have demonstrated that atRA influences the activities of genes responsible for the pathogenesis of hypertension and its complications. 2,3,6,8 Dechow et al 6 reported that atRA reduced blood pressure in the renal damage model. Spontaneously hypertensive rats (SHR) are recognized as genetically hypertensive rats, which resemble, in many aspects, humans with essential hypertension. 9 Chronic atRA treatment prevented medial thickening of intramyocardial and intrarenal arteries and ventricular fibrosis in SHR. 3 However, whether atRA reduces arterial pressure and attenuates myocardial damage in SHR deserves further study.atRA has been shown to regulate the gene expression of components of renin-angiotensin system (RAS), including renin, angiotensin-converting enzyme (ACE), angiotensin (Ang) II, and its type 1 (AT 1 ) receptor. 6,7,10 RAS is critically inv...

Soluble sugars, organic acids and volatiles are important components that determine unique fruit flavor and consumer preferences. However, the metabolic dynamics and underlying regulatory networks that modulate overall flavor formation during fruit development and ripening remain largely unknown for most fruit species.In this study, by integrating flavor-associated metabolism and transcriptome data from 12 fruit developmental and ripening stages of Actinidia chinensis cv Hongyang, we generated a global map of changes in the flavor-related metabolites throughout development and ripening of kiwifruit.Using this dataset, we constructed complex regulatory networks allowing to identify key structural genes and transcription factors that regulate the metabolism of soluble sugars, organic acids and important volatiles in kiwifruit. Moreover, our study revealed the regulatory mechanism involving key transcription factors regulating flavor metabolism. The modulation of flavor metabolism by the identified key transcription factors was confirmed in different kiwifruit species providing the proof of concept that our dataset provides a suitable tool for clarification of the regulatory factors controlling flavor biosynthetic pathways that have not been previously illuminated.Overall, in addition to providing new insight into the metabolic regulation of flavor during fruit development and ripening, the outcome of our study establishes a foundation for flavor improvement in kiwifruit.

Designing catalytic materials with enhanced stability and activity is crucial for sustainable electrochemical energy technologies. RuO2 is the most active material for oxygen evolution reaction (OER) in electrolysers aiming at producing ‘green’ hydrogen, however it encounters critical electrochemical oxidation and dissolution issues during reaction. It remains a grand challenge to achieve stable and active RuO2 electrocatalyst as the current strategies usually enhance one of the two properties at the expense of the other. Here, we report breaking the stability and activity limits of RuO2 in neutral and alkaline environments by constructing a RuO2/CoOx interface. We demonstrate that RuO2 can be greatly stabilized on the CoOx substrate to exceed the Pourbaix stability limit of bulk RuO2. This is realized by the preferential oxidation of CoOx during OER and the electron gain of RuO2 through the interface. Besides, a highly active Ru/Co dual-atom site can be generated around the RuO2/CoOx interface to synergistically adsorb the oxygen intermediates, leading to a favourable reaction path. The as-designed RuO2/CoOx catalyst provides an avenue to achieve stable and active materials for sustainable electrochemical energy technologies.

Summary The randomized extended Kaczmarz and Gauss–Seidel algorithms have attracted much attention because of their ability to treat all types of linear systems (consistent or inconsistent, full rank or rank deficient). In this paper, we present tight upper bounds for the convergence of the randomized extended Kaczmarz and Gauss–Seidel algorithms. Numerical experiments are given to illustrate the theoretical results.

Camellia is a well-known ornamental flower native to Southeast of Asia, including regions such as Japan, Korea and South China. However, most species in the genus Camellia are cold sensitive. To elucidate the cold stress responses in camellia plants, we carried out deep transcriptome sequencing of ‘Jiangxue’, a cold-tolerant cultivar of Camellia japonica, and approximately 1,006 million clean reads were generated using Illumina sequencing technology. The assembly of the clean reads produced 367,620 transcripts, including 207,592 unigenes. Overall, 28,038 differentially expressed genes were identified during cold acclimation. Detailed elucidation of responses of transcription factors, protein kinases and plant hormone signalling-related genes described the interplay of signal that allowed the plant to fine-tune cold stress responses. On the basis of global gene regulation of unsaturated fatty acid biosynthesis- and jasmonic acid biosynthesis-related genes, unsaturated fatty acid biosynthesis and jasmonic acid biosynthesis pathways were deduced to be involved in the low temperature responses in C. japonica. These results were supported by the determination of the fatty acid composition and jasmonic acid content. Our results provide insights into the genetic and molecular basis of the responses to cold acclimation in camellia plants.

Chronic atRA treatment activates gene and protein expression of APJ and apelin and reduces blood pressure in SHR, suggesting that atRA may regulate the balance between apelin-APJ and angiotensin II-AT(1) signaling and have potential clinical value in the prevention and treatment of human hypertension.

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