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961.
The antiallergic activity of Polygoni cuspidati radix (PR) and the mechanism of action by which it functions were investigated in this study. The extract of PR exhibited potent inhibitory activity in mast cells; its IC50 values were 62 +/- 2.1 microg/ml for RBL-2H3 mast cells and 46 +/- 3.2 microg/m for bone marrow-derived mast cells by antigen stimulation, and it also suppressed the expression of tumor necrosis factor-alpha and interleukin-4 in RBL-2H3 cells. According to the in vivo animal allergy model, it inhibited a local allergic reaction, passive cutaneous anaphylaxis, in a dose-dependent manner. With regard to its mechanism of action, PR inhibited the activating phosphorylation of Syk, a key signaling protein for the activation of mast cells. It also suppressed Akt and the mitogen-activated protein kinases ERK1/2, p38, and JNK, which are critical for the production of various inflammatory cytokines in mast cells. The results of the study indicate that the antiallergic activity of PR is mediated through the inhibition of histamine release and allergic cytokine production by the inhibition of Syk activating phosphorylation in mast cells.  相似文献   
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The kidney glomerulus plays a pivotal role in ultrafiltration of plasma into urine and also is the locus of kidney disease progressing to chronic renal failure. We have focused proteomic analysis on the glomerulus that is most proximal to the disease locus. In the present study, we aimed to provide a confident, in-depth profiling of the glomerulus proteome. The glomeruli were highly purified from the kidney cortex from a male, 68-year-old patient who underwent nephroureterectomy due to ureter carcinoma. The patient was normal in clinical examinations including serum creatinine and urea levels and liver function, and did not receive any chemotherapy and radiotherapy. The cortical tissue was histologically normal, and no significant deposition of immunoglobulins and complement C3 was observed. We employed a novel strategy of protein separation using 1D (SDS-PAGE) and 2D (solution-phase IEF in combination with SDS-PAGE) prefractionation prior to the shotgun analysis with LC-MS/MS. The protein prefractionation produced 90 fractions, and eventually provided a confident set of identified proteins consisting of 6686 unique proteins (3679 proteins with two or more peptide matches and 3007 proteins with one peptide match), representing 2966 distinct genes. All the identified proteins were annotated and classified in terms of molecular function and biological process, compiled into 1D and 2D protein arrays, consisting of 15 and 75 sections, corresponding to the protein fractions which were defined by MW and pI range, and deposited on a Web-based database (http://www.hkupp.org). The most remarkable feature of the glomerulus proteome was a high incidence of identification of cytoskeleton-related proteins, presumably reflecting the well-developed, cytoskeletal organization of glomerular cells related to their physiological functions.  相似文献   
963.
Wei  Long  Zhao  Haiyan  Wang  Baoxiang  Wu  Xinyi  Lan  Rujia  Huang  Xu  Chen  Bo  Chen  Gang  Jiang  Chaoqiang  Wang  Jinlan  Liu  Yan  Zheng  Qingsong 《Journal of Plant Growth Regulation》2022,41(6):2108-2121

This study evaluated the effects of foliar spraying melatonin (MT) on the growth of salt-stressed rice. Seedlings were treated with 50 and 100 mM of NaCl and different concentrations of MT (25, 50, 100, 200, 300, and 400 μM) for 14 days. Different concentrations of MT could promote plant growth significantly under salt stress, particularly at concentrations of 200, 300, and 400 μM. A concentration of 200 μM MT was considered as optimal and used in a subsequent experiment on biomass, water content, antioxidation, mineral nutrition, salt absorption, and distribution of salt-stressed rice seedlings. Results showed that MT’s promoting effect on plant growth under salt stress was evident with time, particularly under high salt stress. MT improved the activities of antioxidant enzymes, reduced membrane lipid peroxidation, alleviated cell injury in plant leaves, and increased N content and Si accumulation in the leaves and roots under salt stress, particularly under high salinity. This compound also inhibited Na uptake and upward transport, but it promoted or maintained the uptake and upward transport of K and Ca in salt-stressed rice. Thus, MT improved the ion homeostasis of K/Na and Ca/Na in plants, particularly in the leaves. Foliar spraying of MT alleviated salt stress on rice by promoting nutrient accumulation or translocation, improving ion homeostasis, which is evident in the leaves, and consequently enhancing its salt resistance. The antioxidative improvement caused by MT might also be related to the improved ion homeostasis.

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964.
Xia  Xiu-Jiao  Shen  Hong  Zhi  Hui-Lin  Zhong  Yan  Sang  Bo  Lv  Wen-Wen  Li  Qiu-Ping  Liu  Ze-Hu 《Mycopathologia》2022,187(2-3):189-197
Mycopathologia - Deep cutaneous fungal infections including deep dermatophytosis are responsible for significant morbidity and mortality, especially in immunocompromised patients. Variable and...  相似文献   
965.
Chen  Chen  Li  Bo  Chen  Haotian  Qin  Yuhui  Cheng  Junying  He  Bo  Wan  Yixuan  Zhu  Dongyong  Gao  Fabao 《Neurochemical research》2022,47(8):2254-2262

We aimed to explore the protective effects and potential treatment mechanism of Epigallocatechin-3-gallate (EGCG) in an animal model of chronic exposure in a natural high-altitude hypoxia (HAH) environment. Behavioral alterations were assessed with the Morris water maze test. Iron accumulation in the hippocampus was detected by using DAB enhanced Perls’ staining, MRI, qPCR and colorimetry, respectively. Oxidative stress (malondialdehyde, MDA), apoptosis (Caspase-3), and neural regeneration (brain-derived neurotrophic factor, BDNF) were detected by using ELISA and western blotting. Neural ultrastructural changes were evaluated by transmission electron microscopy (TEM). The results showed that learning and memory performance of rats decreased when exposure to HAH environment. It was followed by iron accumulation, dysfunctional iron metabolism, reduced BDNF and the upregulation of MDA and Caspase-3. TEM confirmed the ultrastructural changes in neurons and mitochondria. EGCG reduced HAH-induced cognitive impairment, iron deposition, oxidative stress, and apoptosis and promoted neuronal regeneration against chronic HAH-mediated neural injury.

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