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791.
792.
Gripp-Heel is a homeopathic preparation frequently used in the treatment of respiratory viral infections such as various types of influenza and the common cold. The antiviral activity of Gripp-Heel was studied in vitro on human pathogenic enveloped and nonenveloped RNA and DNA viruses. Before the antiviral assays, in vitro cytotoxicity of Gripp-Heel was determined with cells used for the infection experiments (HeLa, HEp-2, MDCK, BGM) as well as with mitogen-stimulated peripheral blood mononuclear leukocytes. A concentration of 0.5 of the commercially available product slightly reduced cell viability and proliferative capacity, and experiments on antiviral activity were determined starting with a dilution of 0.2 of the commercially available product. The antiviral activity was determined against a broad panel of enveloped and nonenveloped DNA and RNA viruses with plaque reduction assay, cytopathogenic assays, virus titrations, analysis of the viral proteins in virus-specific enzyme immunoassays, and haemagglutination tests. Control substances were acyclovir (10 microg/mL), ribavirin (6 microg/mL), and amantadine hydrochloride (5 microg/mL), depending on the virus type. Gripp-Heel demonstrated dose-dependent in vitro activity (significant reductions of infectivity by 20% to 40%) against Human herpesvirus 1, Human adenovirus C serotype 5, Influenza A virus, Human respiratory syncytial virus, Human parainfluenza virus 3, Human rhinovirus B serotype 14, and Human coxsackievirus serotype A9. The mechanisms of this antiviral activity are still unclear, but type I interferon induction might be a possible explanation. Further research on this homeopathic preparation seems warranted.  相似文献   
793.
The central objective of the current study was to investigate the potential in vitro anti-proliferative properties of the parent ligand, coumarin-dioxy-acetic acid (cdoaH(2)), and its copper complex, copper-coumarin-dioxyacetic acetate-phenathroline ([Cu(cdoa)(phen)(2)]) using four human-derived model cell lines, two neoplastic and two non-neoplastic. In addition, selected mechanistic studies were carried out using one of the neoplastic-derived model cell lines, Hep-G2. Results obtained show that the complex, rather than the ligand, could alter the proliferation of both human neoplastic renal (A-498) and hepatic (Hep-G2) cells. Furthermore, hepatic non-neoplastic cells (Chang) appeared to be less sensitive. However, this effect was not mirrored in non-neoplastic renal (HK-2) cells, a profile shared with cisplatin. The observed anti-proliferative effect appeared to be concentration- and time-dependant, and could be attributed to the complex, rather than any of the component parts, i.e. 1,10-phenanthroline, the coumarin ligand, or the simple metal salt. Furthermore, the complex was shown to decrease DNA synthesis, but did not intercalate with it. Based on IC(50) values, [Cu(cdoa)(phen)(2)] was shown to be almost six times more potent than cisplatin. Moreover, there was no evidence to show that P-glycoprotein (P-gp)-mediated multi-drug resistance (MDR) was likely to play a role in decreasing the anti-proliferative activity of the complex. Cytological stains, analysis of genomic DNA, and biochemical assays [caspase-3 and -9 and cleaved poly(ADP-ribose)-polymerase protein], suggested that cell death could switch between apoptosis and necrosis, and this effect appeared to be concentration-dependent. Additionally, flow cytometric analysis showed that the complex functioned through an alteration in cell cycle progression. Taken together, [Cu(cdoa)(phen)(2)] has been shown to be a more potent anti-proliferative agent than either the ligand or cisplatin, and is capable of altering key biochemical events leading to the execution of apoptotic and/or necrotic cell death, suggesting that it is worthy of further investigation.  相似文献   
794.
Arabinomannan (AMannan) and mannan (Mannan) are major polysaccharides antigens of the mycobacterial capsule. They are highly related to the lipoarabinomannan (LAM) and lipomannan (LM) lipoglycans of the cell wall, known to participate to the immunopathogenesis of mycobacterial infections. Here we present the identification of two related polysaccharides from Mycobacterium kansasii that co-purified with AMannan and Mannan. Structural analysis using GC, MALDI-MS and NMR clearly established these molecules as non-acylated phosphorylated AMannan and Mannan designated P-AMannan and P-Mannan, respectively. These glycoconjugates represent a new source of polysaccharide structural variability in mycobacteria and constitute unique tools for structure-activity relationship studies in order to investigate the role of fatty acids in the biological functions of LAM and LM. The potential participation of these polysaccharides in influencing the outcome of the infection is also discussed.  相似文献   
795.
Epidemiological and animal studies suggest that the alteration of hormonal and metabolic environment during fetal and neonatal development can contribute to development of metabolic syndrome in adulthood. In this paper, we investigated the impact of maternal high-fat (HF) diet on hypothalamic leptin sensitivity and body weight gain of offspring. Adult Wistar female rats received a HF or a control normal-fat (C) diet for 6 wk before gestation until the end of the suckling period. After weaning, pups received either C or HF diet during 6 wk. Body weight gain and metabolic and endocrine parameters were measured in the eight groups of rats formed according to a postweaning diet, maternal diet, and gender. To evaluate hypothalamic leptin sensitivity in each group, STAT-3 phosphorylation was measured in response to leptin or saline intraperitoneal bolus. Pups exhibited similar body weights at birth, but at weaning, those born to HF dams weighed significantly less (-12%) than those born to C dams. When given the HF diet, males and females born to HF dams exhibited smaller body weight and feed efficiency than those born to C dams, suggesting increased energy expenditure programmed by the maternal HF diet. Thus, maternal HF feeding could be protective against adverse effects of the HF diet as observed in male offspring of control dams: overweight (+17%) with hyperleptinemia and hyperinsulinemia. Furthermore, offspring of HF dams fed either C or HF diet exhibited an alteration in hypothalamic leptin-dependent STAT-3 phosphorylation. We conclude that maternal high-fat diet programs a hypothalamic leptin resistance in offspring, which, however, fails to increase the body weight gain until adulthood.  相似文献   
796.

Transport of microbes in the atmosphere allows them to spread and to colonize new habitats. To survive the harsh environmental conditions encountered in the atmosphere, these microorganisms have to possess properties that allow them to resist atmospheric stress. We combined physiological experiments and genome analysis of Pseudomonas syringae strain R10.79, previously isolated from rain, to decipher the strain’s ability to withstand these challenges and identify the mechanisms behind the resistance. We used laboratory experiments to simulate different atmospheric stress factors and evaluated cell survival using fluorescent staining and flow cytometry. We found that while P. syringae R10.79 was resistant to oxidative, osmotic, UVB radiation-induced and freezing stress, it was sensitive to desiccation on surfaces. Strain R10.79 possesses a range of genes that would allow the strain to mitigate atmospheric stresses, such as cold shock and osmotic shock genes as well as genes encoding for properties that relate to UV irradiation resistance. Studying the substrate spectrum of strain R10.79, we uncovered that it can utilize carbon compounds abundant in the atmosphere including acetate, succinate and formate. In addition, strain R10.79 possesses metabolic pathways to utilize formaldehyde and methanol as sole carbon sources. These compounds could support the metabolic activity of strain R10.79 while suspended in the atmosphere during periods with sufficiently high relative humidity. Finally, we found that when growing on acetate, strain R10.79 produces several volatile organic compounds such as isoprene and methanol, for which we propose biochemical pathways and which are relevant for atmospheric chemistry and climate. The results reported in this study will support our general aim at establishing this strain as a model organism to study microbial responses to atmospheric conditions.

  相似文献   
797.
Members of the transforming growth factor (TGF)‐β family govern a wide range of mechanisms in brain development and in the adult, in particular neuronal/glial differentiation and survival, but also cell cycle regulation and neural stem cell maintenance. This clearly created some discrepancies in the field with some studies favouring neuronal differentiation/survival of progenitors and others favouring cell cycle exit and neural stem cell quiescence/maintenance. Here, we provide a unifying hypothesis claiming that through its regulation of neural progenitor cell (NPC) proliferation, TGF‐β signalling might be responsible for (i) maintaining stem cells in a quiescent stage, and (ii) promoting survival of newly generated neurons and their functional differentiation. Therefore, we performed a detailed histological analysis of TGF‐β1 signalling in the hippocampal neural stem cell niche of a transgenic mouse that was previously generated to express TGF‐β1 under a tetracycline regulatable Ca‐Calmodulin kinase promoter. We also analysed NPC proliferation, quiescence, neuronal survival and differentiation in relation to elevated levels of TGF‐β1 in vitro and in vivo conditions. Finally, we performed a gene expression profiling to identify the targets of TGF‐β1 signalling in adult NPCs. The results demonstrate that TGF‐β1 promotes stem cell quiescence on one side, but also neuronal survival on the other side. Thus, considering the elevated levels of TGF‐β1 in ageing and neurodegenerative diseases, TGF‐β1 signalling presents a molecular target for future interventions in such conditions.  相似文献   
798.
Molecularly imprinted polymers (MIPs) for salicylic acid were synthesized and evaluated in aqueous environments in the aim to apply them as drug delivery carriers. One organic MIP and one inorganic MIP based on the sol–gel process were synthesized. The organic MIP was prepared by radical polymerization using the stoichiometric functional monomer, 1‐(4‐vinylphenyl)‐3‐(3,5‐bis(trifluoromethyl)phenyl)urea, which can establish strong electrostatic interactions with the –COOH of salicylic acid. The sol–gel MIP was prepared with 3‐(aminopropyl)triethoxysilane and trimethoxyphenylsilane, as functional monomers and tetraethyl orthosilicate as the crosslinker. While the organic MIPs bound the target specifically in acetonitrile, they exhibited lower binding in the presence of water, although the imprinting factor increased under these conditions, due to reduced non‐specific binding. The sol–gel MIP has a high specificity and capacity for the drug in ethanol, a solvent compatible with drug formulation and biomedical applications. In vitro release profiles of the polymers in water were evaluated, and the results were modelled by Fick's law of diffusion and the power law. Analysis shows that the release mechanism was predominantly diffusion‐controlled. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
799.
The epidermal permeability barrier of mammalian skin is localized in the stratum corneum. Corneocytes are embedded in an extracellular, highly ordered lipid matrix of hydrophobic lipids consisting of about 50% ceramides, 25% cholesterol and 15% long and very long chain fatty acids. The most important lipids for the epidermal barrier are ceramides. The scaffold of the lipid matrix is built of acylceramides, containing ω-hydroxylated very long chain fatty acids, acylated at the ω-position with linoleic acid. After glucosylation of the acylceramides at Golgi membranes and secretion, the linoleic acid residues are replaced by glutamate residues originating from proteins exposed on the surface of corneocytes. Removal of their glucosyl residues generates a hydrophobic surface on the corneocytes used as a template for the formation of extracellular lipid layers of the water permeability barrier. Misregulation or defects in the formation of extracellular ceramide structures disturb barrier function. Important anabolic steps are the synthesis of ultra long chain fatty acids, their ω-hydroxylation, and formation of ultra long chain ceramides and glucosylceramides. The main probarrier precursor lipids, glucosylceramides and sphingomyelins, are packed in lamellar bodies together with hydrolytic enzymes such as glucosylceramide-β-glucosidase and acid sphingomyelinase and secreted into the intercelullar space between the stratum corneum and stratum granulosum. Inherited defects in the extracellular hydrolytic processing of the probarrier acylglucosylceramides impair epidermal barrier formation and cause fatal diseases: such as prosaposin deficiency resulting in lack of lysosomal lipid binding and transfer proteins, or the symptomatic clinical picture of the “collodion baby” in the absence of glucocerebrosidase. This article is part of a Special Issue entitled The Important Role of Lipids in the Epidermis and their Role in the Formation and Maintenance of the Cutaneous Barrier. Guest Editors: Kenneth R. Feingold and Peter Elias.  相似文献   
800.
The development of antigen arrays has provided researchers with great tools to identify reactivities against self or foreign antigens from body fluids. Yet, these approaches mostly do not address antibody isotypes and their effector functions even though these are key points for a more detailed understanding of disease processes. Here, we present a bead array-based assay for a multiplexed determination of antigen-specific antibody levels in parallel with their properties for complement activation. We measured the deposition of C3 fragments from serum samples to reflect the degree of complement activation via all three complement activation pathways. We utilized the assay on a bead array containing native and citrullinated peptide antigens to investigate the levels of IgG, IgM and IgA autoantibodies along with their complement activating properties in serum samples of 41 rheumatoid arthritis patients and 40 controls. Our analysis revealed significantly higher IgG reactivity against the citrullinated fibrinogen β and filaggrin peptides as well as an IgA reactivity that was exclusive for citrullinated fibrinogen β peptide and C3 deposition in rheumatoid arthritis patients. In addition, we characterized the humoral immune response against the viral EBNA-1 antigen to demonstrate the applicability of this assay beyond autoimmune conditions. We observed that particular buffer compositions were demanded for separate measurement of antibody reactivity and complement activation, as detection of antigen-antibody complexes appeared to be masked due to C3 deposition. We also found that rheumatoid factors of IgM isotype altered C3 deposition and introduced false-positive reactivities against EBNA-1 antigen. In conclusion, the presented bead-based assay setup can be utilized to profile antibody reactivities and immune-complex induced complement activation in a high-throughput manner and could facilitate the understanding and diagnosis of several diseases where complement activation plays role in the pathomechanism.  相似文献   
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