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511.
Antibacterial properties of secreted phospholipases A2 (PLA2) have emerged gradually. Group (G) IIA PLA2 is the most potent among mammalian secreted (s) PLA2s against Gram-positive bacteria, but additional antibacterial compounds, e.g. the bactericidal/permeability-increasing protein, are needed to kill Gram-negative bacteria. The mechanisms of binding to the bacterial surface and the killing of bacteria by sPLA2s are based on the positive charge of the PLA2 protein and its phospholipolytic enzymatic activity, respectively. The concentration of GIIA PLA2 is highly elevated in serum of patients with bacterial sepsis, and overexpression of GIIA PLA(2) protects transgenic mice against experimental Gram-positive infection. The synthesis and secretion of GIIA PLA2 are stimulated by the cytokines TNF-alpha, IL-1 and IL-6. Secreted PLA2s may be potentially useful new endogenous antibiotics to combat infections including those caused by antibiotic-resistant bacteria such as methicillin-resistant staphylococci and vancomysin-resistant enterococci. 相似文献
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Alexandra Fischer Michiel ten Hove Liam Sebag-Montefiore Helga Wagner Kieran Clarke Hugh Watkins Craig A Lygate Stefan Neubauer 《BMC developmental biology》2010,10(1):70
Background
It is well established that the immature myocardium preferentially utilises non-oxidative energy-generating pathways. It exhibits low energy-transfer capacity via the creatine kinase (CK) shuttle, reflected in phosphocreatine (PCr), total creatine and CK levels that are much lower than those of adult myocardium. The mechanisms leading to gradually increasing energy transfer capacity during maturation are poorly understood. Creatine is not synthesised in the heart, but taken up exclusively by the action of the creatine transporter protein (CrT). To determine whether this transporter is ontogenically regulated, the present study serially examined CrT gene expression pattern, together with creatine uptake kinetics and resulting myocardial creatine levels, in rats over the first 80 days of age. 相似文献513.
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Background
Patients with Opitz GBBB syndrome present with a variable array of developmental defects including craniofacial, cardiac, and genital anomalies. Mutations in the X-linked MID1 gene, which encodes a microtubule-binding protein, have been found in ~50% of Opitz GBBB syndrome patients consistent with the genetically heterogeneous nature of the disorder. A protein highly related to MID1, called MID2, has also been described that similarly associates with microtubules. 相似文献516.
European eels, Anguilla anguilla, L., are captured in coghill nets at three commercial weirs on the Irish River Shannon during their autumn/winter seaward migration. The variations in daily silver eel catches were analysed in relation to environmental conditions, especially hydrometric and meteorological factors. Three multivariate environmental axes were distinguished with which daily eel catches could be correlated. The relative importance of various hydrometric, meteorological and temporal (seasonality, lunar phase) factors was identified, showing how hydrological and meteorological factors generally obscure the underlying lunar periodicity of the silver eel migrations at Killaloe. 相似文献
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