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Clinical and experimental studies show that angiotensin II (AngII) promotes vascular pathology via activation of AngII type 1 receptors (AT1Rs). We recently reported that NP‐6A4, a selective peptide agonist for AngII type 2 receptor (AT2R), exerts protective effects on human vascular cells subjected to serum starvation or doxorubicin exposure. In this study, we investigated whether NP‐6A4–induced AT2R activation could mitigate AngII‐induced abdominal aortic aneurism (AAA) using AngII‐treated Apoe?/? mice. Male Apoe?/? mice were infused with AngII (1 µg/kg/min) by implanting osmotic pumps subcutaneously for 28 days. A subset of mice was pre‐treated subcutaneously with NP‐6A4 (2.5 mg/kg/day) or vehicle for 14 days prior to AngII, and treatments were continued for 28 days. NP‐6A4 significantly reduced aortic stiffness of the abdominal aorta induced by AngII as determined by ultrasound functional analyses and histochemical analyses. NP‐6A4 also increased nitric oxide bioavailability in aortic tissues and suppressed AngII‐induced increases in monocyte chemotactic protein‐1, osteopontin and proteolytic activity of the aorta. However, NP‐6A4 did not affect maximal intraluminal aortic diameter or AAA incidences significantly. These data suggest that the effects of AT2R agonist on vascular pathologies are selective, affecting the aortic stiffness and proteolytic activity without affecting the size of AAA.  相似文献   
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It is known that tomato (Lycopersicon esculentum) contains bioactive compounds to combat type-2 diabetes. Therefore, it is of interest to document data from the molecular docking analysis of compounds from Lycopersicon esculentum with the insulin receptors to combat type-2 diabetes. We report the binding features of cinnamic acid, chlorogenic acid, gallic acid & glucoside with insulin receptors for further consideration.  相似文献   
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Cellular and Molecular Neurobiology - Activation of μ, δ, and κ opioid receptors by endogenous opioid peptides leads to the regulation of many emotional and physiological responses....  相似文献   
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Russian Journal of Bioorganic Chemistry - A series of novel carbazol-thiazolidinedione hybrid derivatives were designed, synthesised and screened for antimicrobial activity against gram-positive...  相似文献   
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Journal of Physiology and Biochemistry - Hypoxia-inducible factor1 (HIF1) plays a pivotal role in ensuring cells adapt to low-oxygen conditions. Depletion of oxygen, a co-substrate during...  相似文献   
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The unique conformation of the active site in calpains along with the implication of their role in several diseases has prompted widespread research interest in the scientific community. Structural studies devoted to m- and μ-calpains have proposed a two-stage calcium-dependent activation mechanism for calpains. In this work, we performed conventional and targeted molecular dynamics simulations to investigate global and local changes in the structure of the protease core of m-calpain upon calcium binding. Simulations were performed on the protease core of calcium free (pdbid: 1kfu) and calcium bound (pdbid: 3df0) m-calpain with and without the presence of calcium ions. Our results indicate that the inactive, open conformation of the protease core does not transform into the active, closed conformation simply upon removal of constraints from the neighbor domains. The role of other factors, including calcium binding and the subsequent formation of an Arg94–Glu305 inter-domain salt bridge and the change in the orientation of Trp288 side chain, in the activation of the protease core is elicited.  相似文献   
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We studied extent and type of arbuscular mycorrhizal (AM) and septate endophytic (SE) fungal associations in five lycophytes and 50 ferns collected from Eastern and Western Ghats regions. Of the 54 species and one variety (belonging to 31 genera) examined; 54 taxa had AM association and AM fungal structures were absent in Marsilea quadrifolia. This is the first report of AM and SE fungal status for 26 species each. Of the 55 taxa examined, AM morphology has been evaluated for the first time in 51 species. The hydrophytic fern Salvinia molesta was mycorrhizal and non-mycorrhizal at different sites. All the epiphytic and saxicolous species examined were mycorrhizal. The percentage of AM colonization ranged from 22.23 (Christella parasitica) to 82.20 (Adiantum lunulatum) in ferns and 53.46 (Selaginella bryopteris) to 84.34 (Selaginella sp.) in lycophytes. Epiphytic life-forms had the maximum average AM colonization levels, whereas aquatic life-forms had the minimum colonization levels. The percentage root length colonized by septate fungi ranged between 0.59 in Ophioglossum reticulatum and 16.36 in Pteris pellucida. The root length with AM and SE fungal structures as well as their total colonization significantly varied among the taxa examined. Most of the lycophytes and ferns had intermediate-type of AM morphology with a few exhibiting Paris-type. AM fungal spore numbers ranged from 1.0 (Angiopteris evecta, Pteridium aquilinum) to (Nephrolepis exaltata) 9.3 spores per 25 g soil and varied significantly among taxa. AM fungal spore morphotypes belonging to Claroideoglomus, Funneliformis, Glomus and Rhizophagus were recorded.  相似文献   
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