Cucurbitacins from Ecballium elaterium juice increase the binding of bilirubin and ibuprofen to albumin in human plasma

Ecballium elaterium, a medicinal plant, whose fruit juice is used for the treatment of jaundice in folk medicine, has been reported as being capable of decreasing bilirubinemia in animals with jaundice [H.H. Elayan, M.N. Garaibeh, S.M. Zmeili, S.A. Salhab, Effects of Ecballium elaterium juice on serum bilirubin concentration in male rats, Int. J. Crude Drug Res. 27 (1989) 227-234]. The aim of this study is to identify the Ecballium elaterium components, which are able to modify the binding of bilirubin to albumin. The juice is fiber-free but contains proteins, lipids, sugars, and minerals. The extract of the juice, analyzed by liquid chromatography-electrospray ionization-mass spectrometry (LC-ESI-MS), contains cucurbitacins (Cuc) B, D, E, and I as well as several glycosylated compounds. Human plasma containing no or serial concentrations of Ecballium elaterium components were prepared and the direct bilirubin (DB) and total bilirubin (TB) were determined by the Jendrassik and Grof method. Our results showed that Cuc D, E, and B decreased the levels of DB and TB in plasma, while Cuc I, glycosyl derivatives, and proteins of the juice did not modify the bilirubin levels. The binding of domain specific ligands to HSA, bilirubin (domain IIA), and ibuprofen (domain IIIA), were studied in the absence and presence of Cuc D, E, and I, by fluorescence spectroscopy. The values of binding constant K(a) and binding site number n, determined by Scatchard method, increased for the both ligands only in the presence of Cuc E and D. Cuc I decreased slightly the K(a) of ibuprofen, suggesting an interaction with the domain IIIA of the protein. As a conclusion, Cuc E, D, and B produce rearrangement in the structure of albumin leading to increase the binding of domain specific ligands, ibuprofen and bilirubin.     

Burning Forests,Rising Power: Towards a Constitutionality Process in Mount Carmel Biosphere Reserve

Powerful states and elites frequently manage protected areas with little or no concern for historic land uses, people, or governance practices, justified by ideologies that portray these areas as “pure nature” to be protected from humans. New international participatory platforms, such as the UNESCO Man and Biosphere Program, coupled with strategic active agency, have provided an opportunity for challenging the fortress model of conservation in Israel. We examine the change in Israel’s government ecological policies following its failure in managing the Carmel forests, whereby its bargaining power with the local Druze-Arab minority was significantly reduced, opening a window of opportunity for the Druze to take advantage of new UNESCO rules on local participation to create management institutions for the local forest commons.     

Protection of vascular smooth muscle cells by over-expressed methionine sulphoxide reductase A: Role of intracellular localization and substrate availability

Methionine sulphoxide reductase A (MSRA) that reduces methionine-S-sulphoxide back to methionine constitutes a catalytic antioxidant mechanism to prevent oxidative damage at multiple sub-cellular loci. This study examined the relative importance of protection of the cytoplasm and mitochondria by MSRA using A-10 vascular smooth muscle cells, a cell type that requires a low level of reactive oxygen species (ROS) for normal function but is readily damaged by higher concentrations of ROS. Adenoviral over-expression of human MSRA variants, targeted to either mitochondria or the cytoplasm, did not change basal viability of non-stressed cells. Oxidative stress caused by treatment with the methionine-preferring oxidizing reagent chloramine-T decreased cell viability in a concentration-dependent manner. Cytoplasmic MSRA preserved cell viability more effectively than mitochondrial MSRA and co-application of S-methyl-L-cysteine, an amino acid that acts as a substrate for MSRA when oxidized, further increased the extent of protection. This suggests an important role for an MSRA catalytic antioxidant cycle for protection of the cytoplasmic compartment against oxidative damage.     

Surface layers of Clostridium difficile endospores

Clostridium difficile is an important human pathogen and one where the primary cause of disease is due to the transmission of spores. We have investigated the proteins found in the outer coat layers of C. difficile spores of pathogenic strain 630 (CD630). Five coat proteins, CotA, CotB, CotCB, CotD, and CotE, were shown to be expressed on the outer coat layers of the spore. We demonstrate that purified spores carry catalase, peroxiredoxin, and chitinase activity and that this activity correlates with the predicted functions of three spore coat proteins identified here, CotCB, CotD, and CotE. CotCB and CotD are putative manganese catalases, and CotE is a novel bifunctional protein with peroxiredoxin activity at its amino terminus and chitinase activity at its carboxy terminus. These enzymes could play an important role in coat assembly by polymerizing protein monomers in the coat. CotE, in addition to a role in macromolecular degradation, could play an important role in inflammation, and this may be of direct relevance to the development of the gastrointestinal symptoms that accompany C. difficile infection. Although specific enzyme activity has not yet been assigned to the proteins identified here, this work provides the first detailed study of the C. difficile spore coat.     

Nicotine metabolism in healthy smokers and patients with cardiovascular diseases

In this study, we measured the excretion rate of nicotine and its two major metabolites, cotinine and trans-3′-hydroxycotinine (THOC), in the urine of 25 healthy smokers and 15 smokers who underwent a coronary artery bypass surgery or coronary angioplasty. After 1 day of smoking cessation, urine samples were collected in the morning, before smoking two cigarettes, and then three times after smoking, approximately 4 h apart. The results show that (i) in healthy smokers, nicotine and its two major metabolites were present at high concentration in the first urine sample after smoking, (ii) in smokers with cardiovascular disease nicotine and cotinine were less excreted whereas THOC was more excreted, mainly in the second urine sample. We conclude that this shift in nicotine metabolism may contribute to smoking-induced cardiovascular disease. (Mol Cell Biochem xxx: 241–244, 2005)     

Crop rotation associating a legume and the nickel hyperaccumulator <Emphasis Type="Italic">Alyssum murale</Emphasis> improves the structure and biofunctioning of an ultramafic soil

Nickel (Ni) agromining aims to phytoextract heavy metals using hyperaccumulators whilst at the same time rehabilitating ultramafic soils. After removing the bioavailable metal, ultramafic soils are improved in terms of their agronomic properties with the aim of future agricultural uses. The low fertility of ultramafic soils can be compensated by integrating legumes already used in traditional agro-systems because of their importance in soil nitrogen enrichment. However, few studies have evaluated the potential profits of legumes on Ni agromining and their potential benefits on soil biological fertility. Here, we characterized the effect of a crop rotation with two plants, a legume (Vicia sativa) and a hyperaccumulator (Alyssum murale), on the phytoextraction efficiency and on soil structure and biofunctioning. A pot experiment was set up in controlled conditions to grow A. murale and four treatments were tested: rotation with V. sativa (Ro), fertilized mono-culture (FMo), non-fertilized mono-culture (NFMo) and bare soil without plants (BS). No significant difference was found between the Ro and NFMo treatments for the dry biomass yield. However, the Ro treatment showed the highest Ni concentrations ([Ni]) in A. murale shoots compared to FMo and NFMo treatments. The Ro treatment plants had more than twice as many leaves [Ni] compared to FMo. Soil physico-chemical analyses showed that the Ro treatment was better structured and showed the highest presence of bacterial micro-aggregates, as well as less non-aggregated particles. Legumes integration in Ni-agromining systems could be a pioneering strategy to reduce chemical inputs and to improve soil biofunctioning and thus fertility.     

Binding of a 2-pyridyl moiety to a B/Sn bidentate Lewis acid

Reaction of the bidentate Lewis acid 1,2-Fc(SnMe₂Cl)(B(Me)Cl) (1, Fc = 1,2-ferrocenylene) with 2-trimethylstannylpyridine gave a complex (2), in which the 2-pyridyl group forms a bridge between the Lewis acidic tin and boron centers. The structure of 2 was confirmed by multinuclear and two-dimensional NMR, single crystal X-ray diffraction, and elemental analysis. The crystal structure shows that the pyridyl moiety is positioned endo relative to the substituted Cp ring and UV-Vis spectroscopy revealed an enhancement of the ferrocene-centered dd transition in comparison to related complexes with pyridine as a terminal ligand.     

Is Quality and Completeness of Reporting of Systematic Reviews and Meta-Analyses Published in High Impact Radiology Journals Associated with Citation Rates?

Purpose

The purpose of this study is to determine whether study quality and completeness of reporting of systematic reviews (SR) and meta-analyses (MA) published in high impact factor (IF) radiology journals is associated with citation rates.

Methods

All SR and MA published in English between Jan 2007–Dec 2011, in radiology journals with an IF >2.75, were identified on Ovid MEDLINE. The Assessing the Methodologic Quality of Systematic Reviews (AMSTAR) checklist for study quality, and the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) checklist for study completeness, was applied to each SR & MA. Each SR & MA was then searched in Google Scholar to yield a citation rate. Spearman correlation coefficients were used to assess the relationship between AMSTAR and PRISMA results with citation rate. Multivariate analyses were performed to account for the effect of journal IF and journal 5-year IF on correlation with citation rate. Values were reported as medians with interquartile range (IQR) provided.

Results

129 studies from 11 journals were included (50 SR and 79 MA). Median AMSTAR result was 8.0/11 (IQR: 5–9) and median PRISMA result was 23.0/27 (IQR: 21–25). The median citation rate for SR & MA was 0.73 citations/month post-publication (IQR: 0.40–1.17). There was a positive correlation between both AMSTAR and PRISMA results and SR & MA citation rate; ρ=0.323 (P=0.0002) and ρ=0.327 (P=0.0002) respectively. Positive correlation persisted for AMSTAR and PRISMA results after journal IF was partialed out; ρ=0.243 (P=0.006) and ρ=0.256 (P=0.004), and after journal 5-year IF was partialed out; ρ=0.235 (P=0.008) and ρ=0.243 (P=0.006) respectively.

Conclusion

There is a positive correlation between the quality and the completeness of a reported SR or MA with citation rate which persists when adjusted for journal IF and journal 5-year IF.     

Recovery of ultramafic soil functions and plant communities along an age-gradient of the actinorhizal tree Ceuthostoma terminale (Casuarinaceae) in Sabah (Malaysia)

Plant and Soil - Non- or minimally invasive methods are urgently needed to characterize and monitor crop root systems to foster progress in phenotyping and general system understanding. Electrical...