Nucleotide diversity and minisatellite in chloroplast Asp(GUC)–Thr(GGU) region in Elymus trachycaulus complex, Elymus alaskanus and Elymus caninus

Nucleotide variation in chloroplast Asp(GUC)–Thr(GGU) intergenic region and genetic relationships among this group were examined among Elymus trachycaulus complex, Elymus alaskanus and Elymus caninus. The estimates of nucleotide diversity (π) ranged from 0.00111 for Elymus virescens to 0.03086 for E. caninus. Highest nucleotide diversity was found for E. caninus among the taxa analyzed here and followed by Elymus hyperarcticus. E. virescens accessions are genetically very uniform. Phylogenetic analysis suggested that E. caninus is paraphyletic. Elymus violaceus is genetically distinct from both E. alaskanus and E. trachycaulus. Our result indicates that Asp (GUC)–Thr (GGU) intergenic region has a high rate of evolutionary in Elymus species. Large indels detected in this region appear to have a highly rate of evolution and are thus more prone to homoplasy. We also first reported a minisatellite discovered in Asp (GUC)–Thr (GGU) region in Elymus species. The minisatellite identified here is an excellent candidate marker for studying population structures of Elymus species.     

An antiferromagnetically coupled trinuclear Cu(II) complex containing μ(O,O′), μ(O) carboxylates and μ(O) phenoxide bridges

The trinuclear complex [L₂Cu₃(CF₃CO₂)₄] (1) has been synthesized and its crystal structure determined. It consists of a linear arrangement of Cu(II) centers. The central copper atom is bonded to six oxygen atoms and has a tetragonally distorted octahedral geometry, while the terminal copper atoms are bonded to three oxygen and two nitrogen atoms and show a distorted square pyramidal geometry. The complex shows di-μ(O,O′) syn-syn carboxylate bridging as well as monoatomic (μ-O) bridging, along with phenolate (μ-O) oxygen bridging. Cryomagnetic investigations in the range 2-300 K revealed an antiferromagnetic spin exchange interaction with J = −95.7 cm⁻¹, based on the isotropic exchange model H_ex = −2J[S₁ · S₂ + S₂ · S₃].     

2(S),4(R)-4-(β-d-Galactopyranosyloxy)-4-isobutyl-glutamic acid: A new amino acid in Reseda odorata

2(S),4(R)-4-(β-d-Galactopyranosyloxy)-4-isobutylglutamic acid (I) has been isolated from the flowers of Reseda odorata, wherein it occurs in substantial quantity. Hydrolysis of I gives d-galactose, 2(S),4(R)-4-hydroxy-4-isobutylglutamic acid (II) and 3(R),5(S)-3-hydroxy-3-isobutyl-2-pyrrolidone-5-carboxylic acid (III) and its treatment with nitrous acid yields a galactoside of a non-nitrogenous hydroxy acid lactone (IV). The structures of I and its degradation products are supported by PMR, ¹³C-NMR and other spectroscopic methods. ¹³C-NMR spectroscopy of the model compound 2-(β-d-galactopyranosyloxy)isobutyric acid confirmed the structure of the natural product. The S- (or l-) configuration at C(2) in the amino acid moiety of I has been established by the use of the Clough—Lutz—Jirgenson rule and the R-configuration at C(4) of the same unit has been assigned tentatively. I represents the first example of a glycoside of a higher plant amino acid in which the carbohydrate residue is linked to an aliphatic hydroxy group.     

The effect of hydrogen bonding in two crystal modifications of aquabis(N,N-dimethylglycinato-κN,κO)copper(II): Experimental and theoretical study

From the crystals of trans aquabis(N,N-dimethylglycinato-κN,κO)copper(II) dihydrate (compound 1, space group P2₁2₁2₁) novel crystal structure of trans aquabis(N,N-dimethylglycinato-κN,κO)copper(II) (compound 2, space group Pbca) was obtained and analysed by X-ray diffraction. In the crystal structure 1, the O-H?O hydrogen bonds form three-dimensional network. In the crystal structure 2, two-dimensional layers stacking to each other are formed, with non-polar N,N-dimethyl groups placed on the opposite sides of the layers, and with the polar part in the middle forming CO?O-H and C-H?O hydrogen bonds. Different hydrogen bonding patterns in 1 and 2 do not pronouncedly affect molecular geometry of the title compound. Molecular mechanics force field suited for studying the properties of bis(amino acidato)copper(II) complexes in the solid state can follow the differences between the experimental molecular structures in the two diverse crystalline surroundings. To make possible direct comparison between crystal lattices, the force field was applied to predict unit cell packing of supposed anhydrous bis(N,N-dimethylglycinato)copper(II) in space group Pbca. Relative intermolecular energies of hypothetic anhydrous crystal and simulated 1 and 2 crystals are discussed. On the basis of experimental and theoretical results we conclude that the main effect of two water molecules of crystallisation in 1 is to stabilise the crystal packing via hydrogen bonding, whilst similar pyramidal copper(II) coordination geometry in 1 and 2 is due to axially coordinated water molecule and its intermolecular interactions.     

Maintenance of lower proportions of (n − 6) eicosanoid precursors in phospholipids of human plasma in response to added dietary (n − 3) fatty acids

Competition between the (n ? 3) and (n ? 6) types of highly unsaturated fatty acids can diminish the abundance of (n ? 6) eicosanoid precursors in a tissue, which in turn can diminish the intensity of tissue responses that are mediated by (n ? 6) eicosanoids. The mixture of 20- and 22-carbon highly unsaturated fatty acids maintained in the phospholipids of human plasma is related to the dietary intake of 18:2 (n ? 6) and 18:3 (n ?3) by empirical hyperbolic equations in a manner very similar to the relationship reported for laboratory rats (Lands, W.E.M., Morris, A. and Libelt, B. (1990) Lipids 25, 505–516). Analytical results from volunteers ingesting self-selected diets showed an inter-individual variance for the proportion of (n ? 6) eicosanoid precursors in the fatty acids of plasma phospholipids of about 5%, but the variance among multiple samples taken from the same individual throughout the day was less (about 3%), closer to the experimental variance of the analytical procedure (about 1%). The reproducibility of the results makes it likely that analysis of fatty-acid composition of plasma lipids from individuals will prove useful in estimating the diet-related tendency for severe thrombotic, arthritic of other disorders that are mediated by (n ? 6) eicosanoids. Additional constants and terms were included in the equations to account for the effects of 20- and 22-carbon highly unsaturated (n ? 3) fatty acids in the diet. A lower constant for the 20- and 22-carbon (n ? 3) fatty acids compared to that for the 18-carbon (n ? 3) fatty acid in decreasing the ability of dietary 18:2 (n ? 6) to maintain 20:4 (n ? 6) in tissue lipids confirmed the greater competitive effectiveness of the more highly unsaturated n ? 3 fatty acids in the elongation/ desaturation process. Also, a lower constant for direct incorporation of 20-carbon fatty acids of the n ? 6 vs. the n ? 3 type indicated a greater competitive effectiveness of 20:4 (n ? 6) relative to 20:5 (n ? 3) in reesterification after release from tissue lipids. The equations may be used in reverse to estimate the dietary intakes of the (n ? 3) and (n ? 6) fatty acids by using the composition of the fatty acids that had been maintained in plasma lipids.     

Study of the inclusion of the (R)- and (S)-camphor enantiomers in α-cyclodextrin by X-ray crystallography and molecular dynamics

The inclusion of (R)- and (S)-camphor compounds in α-cyclodextrin has been studied by X-ray crystallography. The crystal structures of the complexes reveal that one guest molecule is accommodated inside the cavity formed by a head-to-head cyclodextrin dimer. In the crystal lattice, the dimers form layers which are successively shifted by half a dimer. In both (R)- and (S)-cases, the camphor molecule exhibits disorder and occupies three major sites with orientations that can be described as either ‘polar’ or ‘equatorial’. Molecular dynamics simulations performed for the observed complexes indicate that although the carbonyl oxygen of both (R)- and (S)-camphor switches between different hydrogen bonding partners, it maintains the observed mode of ‘polar’ or ‘equatorial’ alignment.     

Why hide? Concealed sex in dominant Arabian babblers (Turdoides squamiceps) in the wild

Striking uniformity exists in humans' preference to conceal sexual activity from conspecifics' view. Yet, little is known about the selective pressures acting upon its evolution. To investigate this question, we studied the cooperatively breeding Arabian babbler (Turdoides squamiceps), which has been suggested being the only other species where dominant individuals conceal sex regularly. We examined whether birds indeed conceal sex and tested different hypotheses postulating that sex concealment functions to avoid predators, signal dominance status, or to avoid social interference. The results showed that the birds concealed sex in all observed cases of copulation, did not prefer to copulate under shelters and concealed mating solicitations from adult conspecifics. In addition, subordinates did not attack dominants who courted the respective female. Hence, none of the tested hypotheses explains these results satisfactorily. We postulate that dominant Arabian babblers conceal sex to maintain cooperation with those helpers they prevent from mating. Empirical desiderata for testing this ‘Cooperation-Maintenance’ hypothesis are discussed.     

β-Diketones in Rhododendron waxes

Chromatographic, mass spectrometric and spectroscopic evidence has been obtained for four β-diketones occurring in the leaf waxes of some members of     

Progress in antischistosomal N,N′-diaryl urea SAR

N,N′-Diaryl ureas have recently emerged as a new antischistosomal chemotype. We now describe physicochemical profiling, in vitro ADME, plasma exposure, and ex vivo and in vivo activities against Schistosoma mansoni for twenty new N,N′-diaryl ureas designed primarily to increase aqueous solubility, but also to maximize structural diversity. Replacement of one of the 4-fluoro-3-trifluoromethylphenyl substructures of lead N,N′-diaryl urea 1 with azaheterocycles and benzoic acids, benzamides, or benzonitriles decreased lipophilicity, and in most cases, increased aqueous solubility. There was no clear relationship between lipophilicity and metabolic stability, although all compounds with 3-trifluoromethyl-4-pyridyl substructures were metabolically stable. N,N′-diaryl ureas containing 4-fluoro-3-trifluoromethylphenyl, 3-trifluoromethyl-4-pyridyl, 2,2-difluorobenzodioxole, or 4-benzonitrile substructures had high activity against ex vivo S. mansoni and relatively low cytotoxicity. N,N-diaryl ureas with 3-trifluoromethyl-4-pyridyl and 2,2-difluorobenzodioxole substructures had the highest exposures whereas those with 4-fluoro-3-trifluoromethylphenyl substructures had the best in vivo antischistosomal activities. There was no direct correlation between compound exposure and in vivo activity.     

Estrogen receptor subtype β2 is involved in neuromast development in zebrafish (Danio rerio) larvae

Estrogens are known to play a role in both reproductive and non-reproductive functions in mammals. Estrogens and their receptors are involved in the development of the central nervous system (brain development, neuronal survival and differentiation) as well as in the development of the peripheral nervous system (sensory-motor behaviors). In order to decipher possible functions of estrogens in early development of the zebrafish sensory system, we investigated the role of estrogen receptor β₂ (ERβ₂) by using a morpholino (MO) approach blocking erβ₂ RNA translation. We further investigated the development of lateral line organs by cell-specific labeling, which revealed a disrupted development of neuromasts in morphants. The supporting cells developed and migrated normally. Sensory hair cells, however, were absent in morphants' neuromasts. Microarray analysis and subsequent in situ hybridizations indicated an aberrant activation of the Notch signaling pathway in ERβ₂ morphants. We conclude that signaling via ERβ₂ is essential for hair cell development and may involve an interaction with the Notch signaling pathway during cell fate decision in the neuromast maturation process.     

Occurrence of (24S)-24-methylcholesta-5, 22E-dien-3β-ol in the diatom Phaeodactylum tricornutum

The principal sterol of the marine diatom Phaedactylum tricornutum was identified as (24S)-24-methylcholesta-5,22E-dien-3β-ol. Two deuterium atoms were incorporated into this sterol when the diatom was cultured in the presence of [CD₃]methionine indicating a 24-methylene intermediate.     

Seed rain and seed bank of Chinese yew (Taxus chinensis var. mairei) population in Tianmu Mountain☆

Seed rain and seed bank of a Chinese yew (Taxus chinensis var. mairei) population in Tianmu Mountain were researched in 2008 and 2009. The seed rain lasted from 16th–23th of October to 5th–14th of December, and the heaviest seed falling period was from 2nd to18th of November. The intensity of seed rain showed a great inter-annual variation, with a good harvest in 2008. The fallen seeds were composed of 49.9% proportion of immature seed, 33.8% proportion of chewed seed and 16.3% proportion of mature seed. The analysis on the soil seed bank under mother forest showed that the number of intact seeds was 122.75 ± 108.08 grain/m² in October, 279.25 ± 210.73 grain/m² in December 2008, and 166.5 ± 165.34 grain/m² in October, 322.5 ± 275.73 grain/m² in December 2009. The increased number of seed was 156.5 ± 222.723 grain/m² in 2008 and 156 ± 275grain/m² in 2009, which showed a significant variation. Large number of intact seeds added into soil seed bank after seed rain each year. The number of intact seeds in soil seed bank decreased 112.75 ± 47.74 grain/m² from December 2008 to October 2009. Large number of intact seeds lost from seed rot and seed predation by animals. The number of seeds in soil bank under bamboo forest was much lower than that of mother tree forest, and the increased number of seeds was 0.63 ± 1.60 grain/m² in 2008 and 2.88 ± 1.86 grain/m² in 2009. The number of seedling was 0.73 ± 1.10 trees/m² in mother tree forest and 0.09 ± 0.35 trees/m² in bamboo forest. Seedling survival ratio was 0.37% in mother tree forest and 10.23% in bamboo forest. The micro-habitat in bamboo forest was fit for seed germination. Birds transported seeds to bamboo forest, and had an important effect on the regeneration of Chinese yew.     

Hidden diversity uncovered in Hygrophorus sect. Aurei (Hygrophoraceae), including the Mediterranean H. meridionalis and the North American H. boyeri, spp. nov.

For many years, the binomial Hygrophorus hypothejus was widely applied to collections from various geographical regions in different continents, assuming a circum-boreal and circum-mediterranean distribution for this species. This hypothesis, however, had never been put to the test. To assess the diversity and species-limits within this complex of yellow-coloured waxcaps, a phylogenetic, morphological and taxonomical investigation into Hygrophorus sect. Aurei and similar species in sect. Olivaceoumbrini was carried out, including material of pan-European origin, as well as the east and west coasts of North America. Following sequencing of the ITS rDNA locus, nine lineages are confirmed in sect. Aurei, most of them highly continentalised. Of these, two are new to science, introduced here as Hygrophorus boyeri sp. nov., from Pinus banksiana and P. rigida forests in eastern North America and from P. muricata and P. contorta forests in western North America, and Hygrophorus meridionalis sp. nov., from Pinus brutia and Pinus halepensis forests in the island of Cyprus and mainland Greece. H. hypothejus is lectotypified and epitypified, and here resolved as a strictly European species, with the old forgotten taxon Hygrophorus siccipes revived as its North American vicariant. The placement of Hygrophorus fuligineus in sect. Aurei is phylogenetically confirmed and detailed comparisons between morphologically similar and phylogenetically affiliated taxa in sect. Aurei and sect. Olivaceoumbrini are provided. The chronic confusion associated with Hygrophorus fuscoalbus, a highly controversial taxon described from Germany nearly two centuries ago and variously interpreted since, is discussed, concluding that this name is too ambiguous to be applied to any currently recognized species.     

R-(-)-β-O-methylsynephrine, a natural product, inhibits VEGF-induced angiogenesis in vitro and in vivo

R-(-)-β-O-methylsynephrine (OMe-Syn) is an active compound isolated from a plant of the Rutaceae family. We conducted cell proliferation assays on various cell lines and found that OMe-Syn more strongly inhibited the growth of human umbilical vein endothelial cells (HUVECs) than that of other normal and cancer cell lines tested. In angiogenesis assays, it inhibited vascular endothelial growth factor (VEGF)-induced invasion and tube formation of HUVECs with no toxicity. The anti-angiogenic activity of OMe-Syn was also validated in vivo using the chorioallantonic membrane (CAM) assay in growing chick embryos. Expression of the growth factors VEGF, hepatocyte growth factor, and basic fibroblast growth factor was suppressed by OMe-Syn in a dose-dependent manner. Taken together, our results indicate that this compound could be a novel basis for a small molecule targeting angiogenesis.     

Révision systématiquedu genre Steginoporella smitt, 1873 (Bryozoa Cheilostomata)

Systematic revision of the genus Steginoporella: until now about eighty species were described. Only twenty recent species and thirty-four fossil ones are maintained. Several species and subspecies are new.The main interest of this revision is to establish a biostratigraphical scale: the settlement of this scale is based on the known stratigraphical distribution and on an attempt of phylogeny.The second advantage is ecological: all recent species live in marine tropical environment. The Steginoporella are good paleoecological indicators.At last, the establishment of a paleobiogeography, even incomplete and not definitive, allows to understand more easily recent distribution of Steginoporella connected with the great events of earth evolution.     

Age-dependent changes in fecal 17β-estradiol and progesterone concentrations in female spider monkeys (Ateles geoffroyi)

The objective of this study was to investigate whether sex steroids decreased with age in female black-handed spider monkeys (Ateles geoffroyi). Fecal concentrations of 17β-estradiol and progesterone (five samples/wk) and the number of ovulatory and anovulatory cycles were compared between adult (n = 3) and aged females (n = 2). All animals (regardless of age) had higher 17β-estradiol concentrations during the fertile than the nonfertile phases. However, during the fertile phase, concentrations of this hormone were significantly higher in adult females. Conversely, progesterone concentrations varied normally throughout the menstrual cycle in both adult and aged animals, with no significant difference between age classes. Similarly, there was no significant effect of age on the number of ovulatory and anovulatory cycles. In conclusion, we inferred that the aged female spider monkeys did not reach menopause, instead they remained in a perimenopausal period characterized by changes in fecal concentrations of ovarian steroids and hypothalamus-hypophysis-ovary axis activity, as well as irregular menstrual flows, for prolonged intervals.