Anthocyanins acylated with gallic acid from chenille plant, Acalypha hispida

Three anthocyanins were isolated from the red flowers of chenille plant, Acalypha hispida Burm. (Euphorbiaceae) by a combination of chromatographic techniques. Their structures were elucidated mainly by homo- and heteronuclear nuclear magnetic resonance spectroscopy and electrospray mass spectrometry, and supported with complete assignments of 13C NMR resonances. The novel pigment, cyanidin 3-O-(2"-galloyl-6"-O-alpha-rhamnopyranosyl-beta-galactopyranoside) (5%), contains the disaccharide robinoside. The other anthocyanins were identified as cyanidin 3-O-(2"-galloyl-beta-galactopyranoside) (85%), and cyanidin 3-O-beta-galactopyranoside (5%). Anthocyanins acylated with gallic acid have previously been identified in species from the families Nymphaeaceae and Aceraceae, and tentatively in Abrus precatorius (Leguminosae).     

Amplified ribosomal DNA restriction analysis in the differentiation of related species of mycobacteria

This study explores the potential of the amplified ribosomal DNA restriction analysis (ARDRA) for intra- and interspecies identification of the genus Mycobacteria. A set of primers was used to amplify part of the 16S and 23S rDNA as well as the 16S-23S rDNA spacer from 121 isolates belonging to 13 different mycobacterial species. Restriction analysis was carried out with five different restriction enzymes, namely CfoI, HaeIII, RsaI, MspI and TaqI. Restriction digestion of the PCR product using CfoI enabled differentiation between 9 of the 13 mycobacterial species, whereas the remaining four enzymes differentiated between 7 of these 13 species. None of the five enzymes distinguished between different isolates of Mycobacterium tuberculosis or between species within the M. tuberculosis complex i.e., M. tuberculosis, M. bovis, M. bovis BCG and M. africanum. Although ARDRA analysis of the 16S-23S rDNA does not seem to have a potential for intraspecies differentiation, it has proven to be a rapid and technically relatively simple method to recognise strains belonging to the M. tuberculosis complex as well as to identify mycobacterial species outside this complex.     

Soluble Fas/Apo-1 (CD95) levels during T cell activation in the presence of acute myelogenous leukemia accessory cells; contributions from local release and variations in systemic levels

Fas (CD95/Apo-1) exists both in membrane-bound and in biologically active soluble (s) forms. Ligation of membrane-expressed Fas can induce apoptosis, and Fas-mediated signaling seems to be involved in T-cell-induced apoptosis of human acute myelogenous leukemia (AML) blasts. The local release of sFas by AML blasts may then function as a protective mechanism by competing with membrane-bound Fas for binding sites on the common Fas ligand (FasL). sFas was released by AML blasts during in vitro culture, and this release was modulated by several cytokines that can be secreted by activated T cells. Increased levels of sFas could be detected during in vitro activation of T cells in the presence of native AML accessory cells, and this was observed both for (i) mitogenic activation of CD4⁺ and CD8⁺ T cell clones derived from acute leukemia patients with therapy-induced leukopenia and (ii) allostimulated activation of T cells derived from normal donors. However, local in vivo levels of sFas will also be influenced by variations in systemic levels. High serum levels of sFas were detected in acute leukemia patients during chemotherapy-induced cytopenia, but these levels decreased during complicating bacterial infections. In contrast, serum levels of sFasL were normal in leukopenic patients. The present results support the hypothesis that local release of sFas can function as a protective mechanism against AML-reactive T cells, but the effects of this local release are, in addition, modulated by variations in systemic levels of sFas (but not sFasL). Received: 9 March 2000 / Accepted: 25 May 2000     

Novel selective thiazoleacetic acids as CRTH2 antagonists developed from in silico derived hits. Part 1

Structure–activity relationships of three related series of 4-phenylthiazol-5-ylacetic acids, derived from two hits emanating from a focused library obtained by in silico screening, have been explored as CRTH2 (chemoattractant receptor-homologous molecule expressed on Th2 cells) antagonists. Several compounds with double digit nanomolar binding affinity and full antagonistic efficacy for human CRTH2 receptor were obtained in all subclasses. The most potent compound was [2-(4-chloro-benzyl)-4-(4-phenoxy-phenyl)-thiazol-5-yl]acetic acid having an binding affinity of 3.7 nM and functional antagonistic effect of 66 nM in a BRET and 12 nM in a cAMP assay with no functional activity for the other PGD2 DP receptor (27 μM in cAMP).     

Can ant‐eating Zodarion spiders (Araneae: Zodariidae) develop on a diet optimal for euryphagous arthropod predators?

Abstract Little attention is paid to the behavioural and physiological adaptations of ant‐eating predators. It is expected that there should be a strong selection for traits related to prey handling, leading to the evolution of morphological, behavioural and nutritional adaptations. Such adaptations may then entail trade‐offs in handling and utilization of alternative prey. To investigate behavioural as well as nutritional adaptations and the occurrence of the corresponding trade‐offs in two ant‐eating spiders of the genus Zodarion [Zodarion atlanticum Pekár & Cardoso and Zodarion germanicum (C. L. Koch)], spiders are reared on two diets: ants (i.e. their preferred prey) and fruit flies (i.e. an alternative prey that is nutritionally optimal for euryphagous spiders). Food consumption is observed and several fitness‐related life‐history parameters are measured. Although spiders readily accept ants, more than one‐third of 35 spiders refuse to consume fruit flies and starve. Furthermore, severe hunger does not induce these individuals to accept fruit flies. Starving spiders die before moulting to the second stadium. Spiders that eat fruit flies increase only little and slowly in weight, and all of these die during the first two stadia. By contrast, spiders on an ant diet increase dramatically in weight, and develop up to the fourth stadium. These data indicate that fruit flies are not suitable for Zodarion, supporting the hypothesis that there are behavioural and nutritional trade‐offs. Taking into account the results of previous studies, it is suggested that nutritional trade‐offs are generally important for stenophagous spiders.     

Quantitative proteomics suggests decrease in the secretogranin‐1 cerebrospinal fluid levels during the disease course of multiple sclerosis

Multiple sclerosis (MS) is a chronic inflammatory disease of the CNS with unknown cause. Proteins with different abundance in the cerebrospinal fluid (CSF) from relapsing‐remitting MS (RRMS) patients and neurological controls could give novel insight to the MS pathogenesis and be used to improve diagnosis, predict prognosis and disease course, and guide in therapy decisions. We combined iTRAQ labeling and Orbitrap mass spectrometry to discover proteins with different CSF abundance between six RRMS patients and 18 neurological disease controls. From 777 quantified proteins seven were selected as biomarker candidates, namely chitinase‐3‐like protein 1, secretogranin‐1 (Sg1), cerebellin‐1, neuroserpin, cell surface glycoprotein MUC18, testican‐2 and glutamate receptor 4. An independent sample set of 13 early‐MS patients, 13 RRMS patients and 13 neurological controls was used in a multiple reaction monitoring verification study. We found the intracellular calcium binding protein Sg1 to be increased in early‐MS patients compared to RRMS and neurological controls. Sg1 should be included in further studies to elucidate its role in the early phases of MS pathogenesis and its potential as a biomarker for this disease.     

The Inotropic Effect of the Active Metabolite of Levosimendan,OR-1896, Is Mediated through Inhibition of PDE3 in Rat Ventricular Myocardium

Aims

We recently published that the positive inotropic response (PIR) to levosimendan can be fully accounted for by phosphodiesterase (PDE) inhibition in both failing human heart and normal rat heart. To determine if the PIR of the active metabolite OR-1896, an important mediator of the long-term clinical effects of levosimendan, also results from PDE3 inhibition, we compared the effects of OR-1896, a representative Ca²⁺ sensitizer EMD57033 (EMD), levosimendan and other PDE inhibitors.

Methods

Contractile force was measured in rat ventricular strips. PDE assay was conducted on rat ventricular homogenate. cAMP was measured using RII_epac FRET-based sensors.

Results

OR-1896 evoked a maximum PIR of 33±10% above basal at 1 μM. This response was amplified in the presence of the PDE4 inhibitor rolipram (89±14%) and absent in the presence of the PDE3 inhibitors cilostamide (0.5±5.3%) or milrinone (3.2±4.4%). The PIR was accompanied by a lusitropic response, and both were reversed by muscarinic receptor stimulation with carbachol and absent in the presence of β-AR blockade with timolol. OR-1896 inhibited PDE activity and increased cAMP levels at concentrations giving PIRs. OR-1896 did not sensitize the concentration-response relationship to extracellular Ca²⁺. Levosimendan, OR-1896 and EMD all increased the sensitivity to β-AR stimulation. The combination of either EMD and levosimendan or EMD and OR-1896 further sensitized the response, indicating at least two different mechanisms responsible for the sensitization. Only EMD sensitized the α₁-AR response.

Conclusion

The observed PIR to OR-1896 in rat ventricular strips is mediated through PDE3 inhibition, enhancing cAMP-mediated effects. These results further reinforce our previous finding that Ca²⁺ sensitization does not play a significant role in the inotropic (and lusitropic) effect of levosimendan, nor of its main metabolite OR-1896.     

Circulating Concentrations of Vitamin B6 and Kidney Cancer Prognosis: A Prospective Case-Cohort Study

Prospective cohort studies have found that prediagnostic circulating vitamin B6 is inversely associated with both risk of kidney cancer and kidney cancer prognosis. We investigated whether circulating concentrations of vitamin B6 at kidney cancer diagnosis are associated with risk of death using a case-cohort study of 630 renal cell carcinoma (RCC) patients. Blood was collected at the time of diagnosis, and vitamin B6 concentrations were quantified using LC-MS/MS. Hazard ratios (HR) and 95% confidence intervals (CI) were calculated using Cox regression models. After adjusting for stage, age, and sex, the hazard was 3 times lower among those in the highest compared to the lowest fourth of B6 concentration (HR_4vs1 0.33, 95% CI [0.18, 0.60]). This inverse association was solely driven by death from RCC (HR_4vs1 0.22, 95% CI [0.11, 0.46]), and not death from other causes (HR_4vs1 0.89, 95% CI [0.35, 2.28], p-interaction = 0.008). These results suggest that circulating vitamin B6 could provide additional prognostic information for kidney cancer patients beyond that afforded by tumour stage.     

Hollow oaks and beetle conservation: the significance of the surroundings

In this study we investigated hollow oaks (Quercus robur, Q. petrea) situated in open landscapes and in forests in Norway in northern Europe, and compared their importance for rare and threatened beetles (Coleoptera). Old, hollow oak trees, both in parks and in forests, were extremely rich in red-listed beetles, and hosted a high proportion of threatened species. The proportion of oak associated species and the mean number of red-listed beetle species per tree was similar in the two site types, but rarefaction showed that for a certain number of individuals, oaks in forests had more threatened and near-threatened species than oaks in parks. The species composition also differed between site types: Park oaks had a higher proportion of species associated with hollows and animal nests, whereas in forests, there was a higher proportion of species depending on dead oak wood in general. Four factors were significant in explaining the richness of red-listed beetles in our study: Tree circumference, cavity decay stage, proportion of oak in the surroundings, and coarse woody debris (CWD) in the surroundings. Forest oaks were smaller, but they still trapped a species richness comparable to that of the larger park oaks—probably a result of high amounts of CWD in the surroundings. We show that oaks in open landscapes and oaks in forest have only partly overlapping beetle assemblages and, thus, cannot be substituted in conservation. Planning for conservation of red-listed beetles associated with this key habitat demands a large scale perspective, both in space and time, as the surroundings have important effects on associated threatened and near threatened species.     

Population structure in the barn swallow,Hirundo rustica: a comparison between neutral DNA markers and quantitative traits

Local adaptation to variable environments can generate clinal variation in morphological traits. Alternatively, similar patterns of clinal variation may be generated simply as a result of genetic drift/migration balance. Teasing apart these different processes is a continuing focus in evolutionary ecology. We compare genetic differentiation at molecular loci and quantitative traits to analyse the effect of these different processes in a morphological latitudinal cline of the barn swallow, Hirundo rustica, breeding across Europe. The results obtained show no structuring at neutral microsatellite loci, which contrasts with positive structuring at five quantitative morphometric traits. This supports the hypothesis that the observed morphometric cline in barn swallows is the result of selection acting in a spatially heterogeneous environment. © 2010 The Linnean Society of London, Biological Journal of the Linnean Society, 2010, 99 , 306–314.