Immunobiological properties of selected natural and chemically modified phenylpropanoids

Effects of natural and structurally transformed lignans compared with stilbenes or stilbenoids on production of nitric oxide (NO) triggered by lipopolysaccharide (LPS) and interferon-γ (IFN-γ), tested under in vitro conditions using murine resident peritoneal macrophages, are reviewed. Relation between the molecular structure and immunobiological activity was investigated, and implication of substituents, double bond stereochemistry, or cyclic attachments (double bond geometry fixation) was assessed. The focus was on lignans and stilbenoids because they were originally selected for a joint project of common interest to phytochemical and pharmacological investigation and because they represent well interesting and universally attractive groups of polyphenols with a feasible potential for therapeutic or nutraceutic utilization

Terahertz underdamped vibrational motion governs protein-ligand binding in solution

Low-frequency collective vibrational modes in proteins have been proposed as being responsible for efficiently directing biochemical reactions and biological energy transport. However, evidence of the existence of delocalized vibrational modes is scarce and proof of their involvement in biological function absent. Here we apply extremely sensitive femtosecond optical Kerr-effect spectroscopy to study the depolarized Raman spectra of lysozyme and its complex with the inhibitor triacetylchitotriose in solution. Underdamped delocalized vibrational modes in the terahertz frequency domain are identified and shown to blue-shift and strengthen upon inhibitor binding. This demonstrates that the ligand-binding coordinate in proteins is underdamped and not simply solvent-controlled as previously assumed. The presence of such underdamped delocalized modes in proteins may have significant implications for the understanding of the efficiency of ligand binding and protein–molecule interactions, and has wider implications for biochemical reactivity and biological function

Purinergic signalling and immune cells

This review article provides a historical perspective on the role of purinergic signalling in the regulation of various subsets of immune cells from early discoveries to current understanding. It is now recognised that adenosine 5'-triphosphate (ATP) and other nucleotides are released from cells following stress or injury. They can act on virtually all subsets of immune cells through a spectrum of P2X ligand-gated ion channels and G protein-coupled P2Y receptors. Furthermore, ATP is rapidly degraded into adenosine by ectonucleotidases such as CD39 and CD73, and adenosine exerts additional regulatory effects through its own receptors. The resulting effect ranges from stimulation to tolerance depending on the amount and time courses of nucleotides released, and the balance between ATP and adenosine. This review identifies the various receptors involved in the different subsets of immune cells and their effects on the function of these cells

Taxonomy of Phanaeus revisited: Revised keys to and comments on species of the New World dung beetle genus Phanaeus MacLeay, 1819 (Coleoptera: Scarabaeidae: Scarabaeinae: Phanaeini)

Edmonds, W. D., Zídek, J. (2012): Taxonomy of Phanaeus revisited: Revised keys to and comments on species of the New World dung beetle genus Phanaeus MacLeay, 1819 (Coleoptera: Scarabaeidae: Scarabaeinae: Phanaeini). Insecta Mundi 2012 (274): 1-108, DOI: http://doi.org/10.5281/zenodo.518209

Taxonomy of Phanaeus revisited: Revised keys to and comments on species of the New World dung beetle genus \u3ci\u3ePhanaeus\u3c/i\u3e MacLeay, 1819 (Coleoptera: Scarabaeidae: Scarabaeinae: Phanaeini)

The purpose of this paper is to reassess the taxonomy of Phanaeus MacLeay (Coleoptera: Scarabaeidae) to accommodate new taxa and changes in taxonomic opinion since the publication of Edmonds’ 1994 revision of the genus. The two subgenera and 13 species groups established by Edmonds (1994) remain unchanged. A revised set of keys with accompanying comments and illustrations separates 54 recognized valid species. Seven recently described valid species are incorporated into the revised classification: Phanaeus blackalleri Delgado-Castillo, 1991; P. bordoni Arnaud, 1996; P. changdiazi Kohlmann and Solís, 2001; P. lecourti Arnaud, 2000; P. martinezorum Arnaud, 2000; P. yecoraensis Edmonds, 2004; and P. zapotecus Edmonds, 2006. The new name Phanaeus sororibispinus Edmonds and Zidek replaces Phanaeus alvarengai Arnaud, 1984, a primary junior homonym of P. alvarengai Pereira and d’Andretta, 1955. Three subspecies recognized in 1994 are elevated to species rank, new status: Phanaeus texensis Edmonds, 1994; P. pilatei Harold, 1863; and P. guatemalensis Harold, 1871. Phanaeus obliquans Bates, 1887 is removed from synonymy and given new status as a valid species. Twelve new junior subjective synonyms (bold) are recognized: P. tridens balthasari Arnaud, 2002 (of P. tridens Castelnau, 1840); P. dzidoi Arnaud, 2000 (of P. palaeno Blanchard, 1843); P. genieri Arnaud, 2002 (of P. amethystinus Harold, 1863); P. prasinus jolyi Arnaud, 2001 (of P. prasinus Harold, 1868); P. kirbyi ledezmai Arnaud, 2002 (of P. kirbyi Vigors, 1825); P. achilles lydiae Arnaud, 2000 (of P. achilles Boheman, 1858); P. chalcomelas grossii Arnaud, 2001 (of P. chalcomelas [Perty, 1830]); P pyrois malyi Arnaud, 2002 (of P. pyrois Bates, 1887); P. tridens moroni Arnaud, 2001 (of P. tridens Castenau, 1840); P. lecourti peruanus Arnaud, 2000 (of P. lecourti Arnaud, 2000); P. endymion porioni Arnaud, 2001 (of P. endymion Harold, 1863); P. pseudofurcosus Balthasar, 1939 (of P. tridens Castelnau, 1840); and P. prasinus trinidadensis Arnaud, 2001 (of P. prasinus Harold, 1868). “Phanaeus viridicollis” Olsoufieff, 1924 (sensu Arnaud 2002) is an unavailable name here considered a color variant of P. pyrois Bates, 1887. Note: Download button at right links to low-res (103 Mb) version. High-res (595 Mbyte) version is attached below as Additional file. The 1994 revision of Phanaeus Macleay by W. D. Edmonds, from Contributions in Science (Natural History Museum of Los Angeles County) is also attached (below) in both low-res (15 Mb) and high-res (68 Mb) versions

Irradiation of the rabbit cornea with UVB rays stimulates the expression of nitric oxide synthases-generated nitric oxide and the formation of cytotoxic nitrogen-related oxidants

Until now, the role of nitric oxide (NO) in cornea irradiated with UVB rays remains unknown. Therefore, we investigated nitric oxide synthase isomers (NOS), enzymes that generate NO, nitrotyrosine (NT), a cytotoxic byproduct of NO, and malondialdehyde (MDA), a byproduct of lipid peroxidation, in rabbit corneas repeatedly irradiated with UVB rays (312 nm, 1x daily for 6 days, the dose per day 1.01 J/cm2) using immunohistochemical methods. The biochemical measurement of nitrite and nitrate has been used for the indirect investigation of NO concentration in the aqueous humor. Results show that in contrast to normal corneas, where of the NOS isomers only endothelial nitric oxide synthase (NOS3) was expressed in a significant amount (in the epithelium and endothelium), in irradiated corneas all NOS isomers (also brain nitric oxide synthase, NOS1, and inducible nitric oxide synthase, NOS2) as well as an indirect measure of ONOO-formation and MDA were gradually expressed, first in the epithelium, the endothelium and the keratocytes beneath the epithelium and finally in the cells of all corneal layers and the inflammatory cells that invaded the corneal stroma. This was accompanied by an elevated concentration of NO in the aqueous humor. In conclusion, repeated irradiation with UVB rays evoked the stimulation of NO production, peroxynitrite formation (demonstrated by NT residues) and lipid peroxidation (evaluated by MDA staining)

The local impact of macrofauna and land‐use intensity on soil nutrient concentration and exchangeability in lowland tropical Peru

Agricultural expansion is a major driver of deforestation which has negative consequences for biodiversity and habitat stability. While sustainable farming is known to be beneficial for biodiversity and crop resilience, little is known about the impact of macrofauna and land‐use intensity on soil quality. In this study, we examine the relative effects of (a) soil macrofauna and (b) land use (primary forest, agroforestry, and annual crop) on element depletion rates, concentration, and exchangeability in standardized soil. We used microcosms with two different mesh sizes, 0.25 mm and 5andnbsp;mm, to exclude and include macrofauna, respectively. The microcosms were incubated for up to a year throughout which samples were collected without replacement. Macrofauna did not have a significant impact on any of the soil parameters which is likely to be due to the low diversity of termites in the sites. Land‐use intensity significantly affected cation depletion rates whose effects increased in order of primary forestandlt;agroforestryandlt;annual crop. At the end of the study, soil Mg+2andnbsp;concentration and Ca/Mg ratio in the agroforestry site differed from other land‐use sites. Our results suggest that both bottom‐up and top‐down interactions have major effects on soil conditions, and the results should therefore be used to advise future research and policy around land‐use management.</p

The local impact of macrofauna and land‐use intensity on soil nutrient concentration and exchangeability in lowland tropical Peru

Agricultural expansion is a major driver of deforestation which has negative consequences for biodiversity and habitat stability. While sustainable farming is known to be beneficial for biodiversity and crop resilience, little is known about the impact of macrofauna and land‐use intensity on soil quality. In this study, we examine the relative effects of (a) soil macrofauna and (b) land use (primary forest, agroforestry, and annual crop) on element depletion rates, concentration, and exchangeability in standardized soil. We used microcosms with two different mesh sizes, 0.25 mm and 5 mm, to exclude and include macrofauna, respectively. The microcosms were incubated for up to a year throughout which samples were collected without replacement. Macrofauna did not have a significant impact on any of the soil parameters which is likely to be due to the low diversity of termites in the sites. Land‐use intensity significantly affected cation depletion rates whose effects increased in order of primary forest&lt;agroforestry&lt;annual crop. At the end of the study, soil Mg+2 concentration and Ca/Mg ratio in the agroforestry site differed from other land‐use sites. Our results suggest that both bottom‐up and top‐down interactions have major effects on soil conditions, and the results should therefore be used to advise future research and policy around land‐use management.</p

Crack growth in Fe-Si (2 wt%) single crystals on macroscopic and atomistic level

This paper is dedicated to experimental and atomistic study of the influence of so called T-stress (acting along the crack plane) on fracture processes in bcc iron. We analyze experimental results from fracture tests performed at room temperature on bcc iron-silicon single crystals with a long edge crack (1¯ 1 0)[1 1 0] (crack plane/crack front). The specimens were loaded in tension mode I under different border conditions inducing different sign of the T-stress. The brittle-ductile behavior at the crack front was monitored on-line via optical microscopy together with external force and prolongation of the specimens. Topology of the specimens has been investigated before and after the fracture tests via the white light interferometer. The microscopic processes produced by the crack itself were studied at 300 K via 3D molecular dynamic (MD) simulations in bcc iron under equivalent boundary conditions and the T-stress was examined by means of stress calculations on the atomistic level. The experimental and atomistic results show that the sign of the T-stress affects the fracture behavior. MD simulations reveal that positive T-stress makes the emission of blunting dislocations 〈1 1 1〉{1 1 2} from the crack front more difficult. As a consequence, higher external loading is needed for crack blunting in the experimental specimens with T > 0 in comparison with the specimen having T < 0