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Milacemide (2-n-pentylaminoacetamide) is a secondary monoamine that in the brain is converted to glycinamide and glycine. This oxidative reaction was suspected to involve the reaction of monoamine oxidase (MAO). Using mitochondrial preparations from tissues that contain MAO-A and -B (rat brain and liver), MAO-A (human placenta), and MAO-B (human platelet and bovine adrenal chromaffin cell), it has been established that mitochondria containing MAO-B rather than MAO-A oxidize (H2O2 production and glycinamide formation) milacemide. The apparent Km (30-90 microM) for milacemide oxidation by mitochondrial MAO-B preparations is significantly lower than that for milacemide oxidation by mitochondrial MAO-A (approximately 1,300 microM). In vitro MAO-B (l-deprenyl and AGN 1135) rather than MAO-A (clorgyline) selectively inhibited the oxidation of milacemide. These in vitro data are matched by ex vivo experiments where milacemide oxidation was compared to oxidation of serotonin (MAO-A) and beta-phenylethylamine (MAO-B) by brain mitochondria prepared from rats pretreated with clorgyline (0.5-10 mg/kg) and l-deprenyl (0.5-10 mg/kg). Furthermore, in vivo experiment demonstrated that l-deprenyl selectively increased the urinary excretion of [14C]milacemide and the total radioactivity with a concomitant decrease of [14C]glycinamide. Such changes were not observed after clorgyline treatment, but were evident only at doses beyond clorgyline selectivity. The present data therefore demonstrate that milacemide is a substrate for brain MAO-B, and its conversion to glycinamide, further transformed to the inhibitory neurotransmitter, glycine, mediated by this enzyme may contribute to its pharmacological activities.  相似文献   
3.
Reovirus particles were isolated from adults in laboratory colonies of the housefly, Musca domestica. These particles were spherical in outline, 57–76 nm in diameter, and were found only in hemocyte cytoplasm, where virions have been disclosed by a new technique. Virions were present in large numbers, and viral inclusion bodies were identified. The virus particles had pentagonal and hexagonal shapes resembling a simple icosahedral structure. The virus was shown to be infectious and pathogenic to adult flies through injection or by feeding them suspensions from flies that had died of the virus. Electron micrographs of midgut sections from infected flies showed that the midgut cells were packed with dark undulating threads which were not present in uninfected flies. However, no virus particles or inclusion bodies could be seen in these cells. On the basis of their association with infected flies, and the similarity to results from other studies on reoviruses and insect viruses, it is suggested that these threads are an alternative replicative form of the reovirus. When the virus suspensions from heavily infected flies were dialyzed against weak alkaline solutions, the threads showed an inner component of coiled material, 12 nm in diameter, inside an envelope with a diameter of 50–83 nm, mean 60.3 ± 7.5, composed of subunits 7–8 nm long and 7–8 nm across.  相似文献   
4.
We compared the effects of Intralipid and dextrose infusion on plasma lecithin:cholesterol acyltransferase (LCAT), plasma lipid profiles and lipolytic activity. We used 5-week-old male Sprague-Dawley rats which were given total parenteral nutrition (TPN) with either Intralipid (3 g/kg body weight) or an equicaloric amount of 25% dextrose in the presence or absence of heparin (1 or 10 IU/ml of TPN). 40 min after the end of 4 h of infusion, plasma LCAT activity was significantly decreased (P less than 0.001), while total cholesterol and free fatty acid levels were significantly (P less than 0.05) increased in rats given Intralipid as compared to those given dextrose. We found associations (P less than 0.005) between LCAT activity and total cholesterol and between LCAT and free fatty acid levels; the coefficients of negative correlation were 0.543 and 0.607, respectively. Concomitantly to the increment in plasma total cholesterol levels, there was a decrease in the high-density lipoprotein (HDL) cholesterol fraction; the latter, which was 40% of the total plasma cholesterol in control and dextrose-infused rats, declined to 9% in rats given Intralipid. Administration of heparin during Intralipid infusion, even up to 10 IU/ml of TPN, did not affect any of these changes. After dextrose infusion, the values of all three parameters were similar to those of the control group. Plasma lipolytic activity was not significantly different between rats given infusion (Intralipid or dextrose) and controls. However, in the presence of heparin, plasma lipolytic activity increased similarly in both infused groups. These data indicate that in young rats, Intralipid infusion leads to an increase in plasma total cholesterol and free fatty acid levels, which correlates with a decrease in LCAT activity; the concurrent decrease in HDL cholesterol levels might account, in part, for the loss of LCAT activity. The administration of heparin results in an elevation of plasma lipolytic activity; however, it does not prevent the hypercholesterolemia, nor the decline in LCAT activity associated with Intralipid infusion.  相似文献   
5.
The relationship between the severity of dengue infection and allergy is still obscure. We conducted an electronic search across 12 databases for relevant articles reporting allergic symptoms, dengue infection, and dengue classification. These studies were categorized according to dengue severity and allergy symptoms, and a meta-analysis was performed by pooling the studies in each category. Among the included 57 articles, pruritus was the most common allergic sign followed by non-specified allergy and asthma(28.6%, 13%, and 6.5%, respectively). Despite the reported significant association of dengue with pruritus and total Ig E level(P \ 0.05), in comparison with non-dengue cases and healthy controls, there was no association between the different severe dengue group with pruritus, skin allergy, food allergy or asthma. However,removing the largest study revealed a significant association between asthma with dengue hemorrhagic fever(DHF) rather than dengue fever(DF). In comparison with DF, DHF was associated with Ig E positivity. Furthermore, specific-Ig E level was higher in secondary DF rather than primary DF. There was a possible association between allergy symptoms and dengue severity progression. Further studies are needed to clarify this association.  相似文献   
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This study evaluates the antimicrobial effects of ethanolic extract of five herbal plants; Guava (Psidium guajava), Sage (Salvia officinalis), Rhamnus (Ziziphusspina Christi), Mulberry (Morusalba L.), and Olive (Oleaeuropaea L) leaves against several microbial population representing Gram positive, Gram negative and Mollicutes; S. aureus, E. coli, Pasteurella multocida, B. cereus, Salmonella Enteritidis and M. gallisepticum using standard agar disc diffusion technique and minimal inhibitory concentration (MIC). Different extracts reveal variable results against the microorganism under study. All extracts have no antibacterial potency for Mycoplasma gallisepticum except Psidium guajava. The results of minimal inhibitory concentration (MIC) and Minimum bactericidal concentration (MBC) of the extracts against the six bacteria ranged from 625 to 5000 μg/ml. The used herbal extract could inhibit the selected microorganism under study with variable minimal inhibitory concentration (MIC) and minimum bactericidal concentration (MBC).  相似文献   
8.
Molecular Biology Reports - A cluster of many risk factors for type 2 diabetes and cardiovascular disease is used to describe the metabolic syndrome (MetS). Moreover, genetic differences associated...  相似文献   
9.
Two series of chalcone/aryl carboximidamide hybrids 4a–f and 6a–f were synthesised and evaluated for their inhibitory activity against iNOS and PGE2. The most potent derivatives were further checked for their in vivo anti-inflammatory activity utilising carrageenan-induced rat paw oedema model. Compounds 4c, 4d, 6c and 6d were proved to be the most effective inhibitors of PGE2, LPS-induced NO production, iNOS activity. Moreover, 4c, 4d, 6c and 6d showed significant oedema inhibition ranging from 62.21% to 78.51%, compared to indomethacin (56.27 ± 2.14%) and celecoxib (12.32%). Additionally, 4c, 6a and 6e displayed good COX2 inhibitory activity while 4c, 6a and 6c exhibited the highest 5LOX inhibitory activity. Compounds 4c, 4d, 6c and 6d fit nicely into the pocket of iNOS protein (PDB ID: 1r35) via the important amino acid residues. Prediction of physicochemical parameters exhibited that 4c, 4d, 6c and 6d had acceptable physicochemical parameters and drug-likeness. The results indicated that chalcone/aryl carboximidamides 4c, 4d, 6c and 6d, in particular 4d and 6d, could be used as promising lead candidates as potent anti-inflammatory agents.  相似文献   
10.

Smooth muscle cells (SMCs) usually express a contractile phenotype in the healthy aorta. However, aortic SMCs have the ability to undergo profound changes in phenotype in response to changes in their extracellular environment, as occurs in ascending thoracic aortic aneurysms (ATAA). Accordingly, there is a pressing need to quantify the mechanobiological effects of these changes at single cell level. To address this need, we applied Traction Force Microscopy (TFM) on 759 cells coming from three primary healthy (AoPrim) human SMC lineages and three primary aneurysmal (AnevPrim) human SMC lineages, from age and gender matched donors. We measured the basal traction forces applied by each of these cells onto compliant hydrogels of different stiffness (4, 8, 12, 25 kPa). Although the range of force generation by SMCs suggested some heterogeneity, we observed that: 1. the traction forces were significantly larger on substrates of larger stiffness; 2. traction forces in AnevPrim were significantly higher than in AoPrim cells. We modelled computationally the dynamic force generation process in SMCs using the motor-clutch model and found that it accounts well for the stiffness-dependent traction forces. The existence of larger traction forces in the AnevPrim SMCs were related to the larger size of cells in these lineages. We conclude that phenotype changes occurring in ATAA, which were previously known to reduce the expression of elongated and contractile SMCs (rendering SMCs less responsive to vasoactive agents), tend also to induce stronger SMCs. Future work aims at understanding the causes of this alteration process in aortic aneurysms.

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