Background: Hypertension (HTN) and type 2 diabetes mellitus (T2DM) are often coincident, and each condition is considered a risk factor for the other. Both occur frequently in the Inner Mongolia region of China. The reasons for differences in risk between Han and Mongolian ethnic groups are not known.
View Article and Find Full Text PDFArsenic is a toxic metalloid for both animals and plants. The signaling molecule melatonin can enhance abiotic stress tolerance, but the effects of As and melatonin on tea plants and the mechanisms of resilience remain unclear. Here we report that excess As causes severe oxidative stress in tea leaves as revealed by significantly reduced maximal photochemical efficiency of photosystem-II, and increased reactive oxygen species accumulation and lipid peroxidation.
View Article and Find Full Text PDFGlobal warming has multifarious effects on crop growth and productivity. Nonetheless, the effects of moderate-high temperatures and melatonin on tea yield and quality remain unclear. In this study, we found that melatonin, a universal growth stimulatory molecule, not only promotes photosynthesis and biomass accumulation in tea plants (Camellia sinensis L.
View Article and Find Full Text PDFInsect herbivores have dramatic effects on the chemical composition of plants. Many of these induced metabolites contribute to the quality (e.g.
View Article and Find Full Text PDFThe phytohormone salicylic acid (SA) is a secondary metabolite that regulates plant growth, development and responses to stress. However, the role of SA in the biosynthesis of flavonoids (a large class of secondary metabolites) in tea ( L.) remains largely unknown.
View Article and Find Full Text PDFTemperature is a major environmental signal that governs plant growth and development. A moderately high ambient temperature alters plant metabolism without significant induction of heat-stress responses. Despite ancillary reports on the negative effect of warmer climate on tea quality, information on specific effect of sub high temperature (SHT) on theanine accumulation is scanty.
View Article and Find Full Text PDFThe unprecedented early spring frost that appears as a cold stress adversely affects growth and productivity in tea ( L.); therefore, it is indispensable to develop approaches to improve the cold tolerance of tea. Here, we investigated the effect of pretreatment with exogenous melatonin on the net photosynthetic rate, the maximum photochemical efficiency of PSII, chlorophyll content, lipid peroxidation, reactive oxygen species (ROS) accumulation, antioxidant potential, and redox homeostasis in leaves of tea plants following cold stress.
View Article and Find Full Text PDFRising CO concentration, a driving force of climate change, is impacting global food security by affecting plant physiology. Nevertheless, the effects of elevated CO on primary and secondary metabolism in tea plants (Camellia sinensis L.) still remain largely unknown.
View Article and Find Full Text PDFFlavonoids are one of the key secondary metabolites determining the quality of tea. Although exogenous brassinosteroid (BR), a steroidal plant hormone, can stimulate polyphenol biosynthesis in tea plants (Camellia sinensis L.), the relevance of endogenous BR in flavonoid accumulation and the underlying mechanisms remain largely unknown.
View Article and Find Full Text PDFSummer grown green tea is less popular due to bitterness and high astringency, which are attributed to high levels of tea polyphenols (TP) and low levels of amino acids (AA) in tea leaves (Camellia sinensis L.). Brassinosteroids (BRs), a group of steroidal plant hormones can regulate primary and secondary metabolism in a range of plant species under both normal and stress conditions.
View Article and Find Full Text PDFLeaf position represents a specific developmental stage that influences both photosynthesis and respiration. However, the precise relationships between photosynthesis and respiration in different leaf position that affect tea quality are largely unknown. Here, we show that the effective quantum yield of photosystem II [ΦPSⅡ] as well as total chlorophyll concentration (TChl) of tea leaves increased gradually with leaf maturity.
View Article and Find Full Text PDFYing Yong Sheng Tai Xue Bao
September 2015
In this study, we determined the vertical distribution of N2O emission rates in tea soils and its adjacent woodland soils. The results showed that total nitrogen contents, N2O fluxes and cumulative emissions in the tea garden and woodland decreased with the increasing depth of the soil layer, and their average values were greater in tea garden than in woodland. Generally, pH, soil water soluble organic nitrogen (WSON), soil microbial biomass nitrogen (MBN), NO(3-)-N and NH(4+)-N contents had a downward trend with the increasing depth of soil layer.
View Article and Find Full Text PDFClin Drug Investig
January 2016
Background And Objectives: Oxidative stress in drug-induced thrombocytopenia (TP) has been discussed. This study was carried out to assess the oxidative stress in patients with normal platelet count (NPC) and TP after linezolid (LZD) treatment and to evaluate if TP caused by LZD is associated with a reduction in antioxidation ability and an increase in lipid peroxidative product in platelets.
Methods: After LZD treatment for 20 days, 44 patients with TP and 73 patients with NPC were included in this study.
Land-use change has a crucial influence on soil respiration, which further affects soil nutrient availability and carbon stock. We monitored soil respiration rates under different land-use types (tea gardens with three production levels, adjacent woodland, and a vegetable field) in Eastern China at weekly intervals over a year using the dynamic closed chamber method. The relationship between soil respiration and environmental factors was also evaluated.
View Article and Find Full Text PDFOur previous study revealed that intracerebroventricular oxytocin (OT) markedly inhibited the restraint stress-priming conditioned place preference (CPP) reinstatement induced by methamphetamine (MAP) via the glutamatergic system. In this study, the effect of microinjection with OT into mesocorticolimbic regions, the medial prefrontal cortex (mPFC) and the dorsal hippocampus (DHC), on the restraint stress-priming CPP reinstatement were further studied. The results showed that a 15-min restraint stress significantly reinstated MAP-induced CPP, which was inhibited by the microinjection of OT (0.
View Article and Find Full Text PDFOxytocin (OT), a neurohypophyseal neuropeptide, affects adaptive processes of the central nervous system. In the present study, we investigated the effects of OT on extracellular levels of glutamate (Glu) and γ-aminobutyric acid (GABA) induced by methamphetamine (MAP) in the medial prefrontal cortex (mPFC) and dorsal hippocampus (DHC) of freely moving mice, using in vivo microdialysis coupled to high-performance liquid chromatography and fluorescence detection. The results showed that OT had no effect on basal Glu levels, but attenuated MAP-induced Glu increase in the mPFC and decrease in the DHC.
View Article and Find Full Text PDFPsychostimulants are frequently abused as a result of their stimulatory effects on several neurotransmitter systems within the central nervous system. Both dopaminergic and glutaminergic neurotransmissions have been closely associated with psychostimulant dependence. In addition to its classical endocrine function in the periphery, oxytocin, an important neurohypophyseal neuropeptide in the central nervous system, has a wide range of behavioral effects, including regulating drug abuse.
View Article and Find Full Text PDFJ Zhejiang Univ Sci B
March 2008
It is important to research the rules about accumulation and distribution of arsenic and cadmium by tea plants, which will give us some scientific ideas about how to control the contents of arsenic and cadmium in tea. In this study, by field investigation and pot trial, we found that mobility of arsenic and cadmium in tea plants was low. Most arsenic and cadmium absorbed were fixed in feeding roots and only small amount was transported to the above-ground parts.
View Article and Find Full Text PDFTea is a widely consumed beverage. However, recent studies revealed that there were an increasing number of cases of tea products exceeding the former maximum permissible concentration (MPC) in China for Pb (2 mg kg(-1)). Tea Pb contamination is an issue affecting trade and consumer confidence.
View Article and Find Full Text PDFWe investigated the scale and causes of Pb contamination in Chinese tea. Lead concentrations in 1,225 tea samples collected nationally between 1999 and 2001 varied from <0.2 to 97.
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