Male Corncrakes Crex crex extend their home ranges by visiting the territories of neighbouring males

Capsule Radiotracked male Corncrake often intruded on the territories of neighbouring males.

Aims To test that intruders' visits are goal-directed, not just a by-product of extended spatial activity during daylight hours.

Methods Using radiotelemetry, we sampled a total of 20 three-day home ranges from 11 tagged males. We recorded daily vocal activity and used a permutation test to see if the movements of tracked males were independent of the position of neighbouring males.

Results The majority of males who had a neighbouring male, up to approximately 600 m from their night calling site, undertook goal-directed visits to the neighbour's territory. Males undertook these visits every day, or every other day, when the neighbours were close. Males undertook visits approximately once every three days when they were more distant. The time spent in the neighbour's territory was longest where the distance between night calling sites was about 200 m. Males tended to be silent in neighbour's territory, apparently to prevent confrontation. Otherwise the distance of neighbouring males did not significantly affect daytime vocal activity. Visiting males tended to sing more often in their home territories.

Conclusions Daily movement of the majority of males was towards the neighbouring male's calling site. We suggest that the purpose of these visits was to seek females. These males may try to drive a female into their territory or gain extra-pair copulation.     

Who Is the King? The α‐Hydroxy‐β‐oxo‐α,β‐enone Moiety or the Catechol B Ring: Relationship between the Structure of Quercetin Derivatives and Their Pro‐Oxidative Abilities

Quercetin and other flavonoids have been reported to exhibit both antioxidant and pro‐oxidant properties. Most studies about the pro‐oxidative ability were conducted in the presence of metal ions, and the essential functional moiety of quercetin responsible for the pro‐oxidative effect is still unclear. In this study, we evaluated the pro‐oxidative abilities in the absence of metal ions of two quercetin derivatives, i.e., quercetin‐3′‐O‐β‐D ‐glucoside ( 1 ) and quercetin‐3‐O‐β‐D ‐glucoside ( 2 ), by assessing DNA cleavage and HO^.‐radical production. The binding mode between these compounds and DNA was studied by fluorescence and viscometric titrations. The results showed that 1 can efficiently induce oxidative damage to plasmid DNA, while 2 shows poor activity. Both 1 and 2 bind to DNA via groove‐binding. These results proved that the α‐hydroxy‐β‐oxo‐α,β‐enone moiety contributes to the pro‐oxidative activity of quercetin.     

Design,synthesis, and evaluation of a selective chemosensor for leucine-rich repeat kinase 2

We describe the design, synthesis, and evaluation of a selective activity probe for leucine-rich repeat kinase 2 (LRRK2), a possible molecular target for the treatment of Parkinson’s disease. Our optimal chemosensor design, termed Nictide-S2, incorporates a phosphorylation-sensitive sulfonamido-oxine fluorophore at an engineered cysteine within the substrate sequence. This design allows for the direct, real-time analysis of LRRK2 kinase activity with a detection limit of 2.5 nM. Under optimized conditions, we measured a Z′ factor of 0.7 demonstrating the potential utility of this assay for inhibitor screening. Off-target kinases capable of phosphorylating Nictide-S2 are identified and an optimized inhibitor cocktail for suppressing background signal is provided. The resulting chemosensor could be utilized to identify LRRK2 inhibitors as well as selectively report on LRRK2 activity in the presence of off-target kinases.     

Quantitative analysis of cytoplasmic actin gene promoter and nuclear polyhedrosis virus immediate-early promoter activities in various tissues of silkworm Bombyx mori using recombinant Autographa californica nuclear polyhedrosis virus as vector

Cassettes harboring luciferase reporter driven by Bombyx mori cytoplasmic actin gene promoter (A3) (671 bp) and B. mori nuclear polyhedrosis virus immediate-early promoter (IE-1) (580 bp) were transferred to the bacmid AcΔEGT to generate the recombinant Autographa californica nuclear polyhedrosis viruses, AcNPVA3Luc and AcNPVIELuc, respectively. Recombinant baculoviruses were injected into the hemocoele of newly ecdysed 5th instar larvae. The activities of the A3 and IE-1 promoters in various tissues were measured by luciferase activity assay and normalized by the copy number of recombinant virus. Results showed that the activity of the A3 promoter was approximately 10-fold higher than the IE-1 promoter. The promoter activities of A3 and IE-1 were highest in the silk gland, followed by fat body, middle gut, Malpighian tubule, and hemocyte. In silk gland, activity of the two promoters was highest in posterior silk gland, followed by middle and anterior silk glands. The difference in promoter activities reflects the growth speed of tissue in silkworm larvae. The activity of the A3 promoter remained unchanged and was not inhibited significantly by viral factors at least 3–4 d post injection of rAcNPV.     

Ligninolytic activity of tropical rainforest basidiomycetes

A total of 116 strains of Brazilian tropical rainforest basidiomycetes were evaluated in terms of their ability to oxidize the dye rhemazol brilliant blue R (RBBR) and guaiacol. Laccase and peroxidase activities were detected by the drop test using solutions of α-naphthol and pyrogallol, respectively. RBBR and guaiacol oxidation occurred in 96.6 and 87.1% of the strains tested, respectively. One hundred strains oxidized both substrates. In the drop test, most strains presented laccase (96.6%) and peroxidase (92.2%) activity. The quick screening method used here can be useful to identify ligninolytic fungal strains to be used in various biotechnological applications. This revised version was published online in November 2006 with corrections to the Cover Date.     

Relationship between immunoglobulin levels and extremes of solar activity

The possible relationship between epidemics and extremes of solar activity has been discussed previously. The purpose of the present study was to verify whether differences in the levels of immunoglobulins (IgA, IgG, IgM) could be noted at the highest (July 1989) and lowest (September 1986) points of the last (21st) and present (22nd) 11-year solar cycle. The work was divided into a 1-month study (covering the month of minimal or maximal solar activity), a 3-month study (1 month before and after the month of minimal or maximal solar activity) and a 5-month study (2 months before and after the month of minimal or maximal solar activity). A trend of a drop-off for all three immunoglobulins was seen on the far side of the maximal point of the solar cycle. Statistical significance was achieved in the 5-month study for IgM (P=0.04), and a strong trend was shown for IgG (P=0.07). Differences between the sexes were also noted.     

Thermal Stability and Activity Regain of Horseradish Peroxidase in Aqueous Mixtures of Imidazolium-Based Ionic Liquids

Thermal deactivation kinetics of horseradish peroxidase (HRP) were studied from 45 to 90 °C in phosphate buffer and 5–25% (v,w/v) 1-butyl-3-methylimidazolium tetrafluoroborate [BMIM][BF₄] and 1-butyl-3-methylimidazolium chloride [BMIM][Cl]. HRP activity at 25 °C was not affected by the presence of ionic liquids up to 20% (v,w/v). Increasing the ionic liquids concentration up to 25% (v,w/v) changed the biphasic character of deactivation kinetics to an apparent single first-order step. The presence of 5–10% (v/v) [BMIM][BF₄] significantly improved HRP thermal stability with lower activation energies for the deactivation second phase (83–87 kJ mol⁻¹). After deactivation, enhanced activity regain of the enzyme, up to 70–80% of the initial activity, was found in 25% (v/v) [BMIM][BF₄] and 10% (w/v) [BMIM][Cl] and correlated to prevalence of the deactivation first phase.     

Correlation of structure to antitumor activities of five derivatives of a beta-glucan from Poria cocos sclerotium

A water-insoluble (1-->3)-beta-D-glucan isolated from fresh sclerotium of Poria cocos was, respectively, sulfated, carboxymethylated, methylated, hydroxyethylated, and hydroxypropylated, to afford five water-soluble derivatives. Their weight-average molecular masses (Mw) and intrinsic viscosities ([eta]) were determined by size-exclusion chromatography combined with laser light scattering (SEC-LLS), LLS, and viscometry in phosphate buffer solution (PBS) at 37 degrees C. The antitumor activities, against Sarcoma 180 tumor cell (S-180) and gastric carcinoma cell strain (MKN-45 and SGC-7901) of the native beta-glucan and the five derivatives, were tested in vitro and in vivo. The Mw values of the five derivatives in PBS were determined to be 3.8 x 10(4), 18.9 x 10(4), 16.0 x 10(4), 76.8 x 10(4), and 224.3 x 10(4), respectively. The high Mw values of the hydroxyethylated and hydroxypropylated derivatives in aqueous solution resulted from aggregation, and their true Mw values obtained in dimethyl sulfoxide were 20.1 x 10(4) and 19.1 x 10(4). The sulfated and carboxymethylated derivatives having DS of 1.0-1.3 show good water solubility, and exist as relatively expanded chains in aqueous solution. Interestingly, the native beta-glucan did not show antitumor activity, whereas the sulfated and carboxymethylated derivatives exhibit significant antitumor activities against S-180 and gastric carcinoma tumor cells. This work showed that good water solubility, relatively high chain stiffness, and moderate molecular mass of the derivatives in aqueous solution contribute beneficial to enhancement of antitumor activity.     

Chemical composition and antidiabetic activity of Opuntia Milpa Alta extracts

Three new compounds, 1 – 3 , and 20 known compounds were isolated from the AcOEt and BuOH extract of edible Opuntia Milpa Alta. The petroleum ether extract was examined by GC and MS. A total of 26 compounds were identified, representing 95.6% of the total extract, phytosterol (36.03%) being the most abundant component, and polyunsaturated fatty acids (18.57%) represented the second largest group, followed by phytol (12.28%), palmitic acid, palmitate (13.54%), vitamin E (4.51%), and other compounds (7.47%). The effects of various extracts from edible Opuntia Milpa Alta (petroleum ether extract, AcOEt extract, BuOH extract, aqueous extract, H₂O parts) and the positive control (received dimethylbiguanide) were tested on streptozotocin (STZ)‐induced diabetic mice. The results indicated that all the treatment groups could significantly decrease blood glucose levels in STZ‐induced diabetic mice compared to the model control group (P<0.01), except the aqueous extract group (P<0.05). Especially, the petroleum ether extract group and the positive control group showed remarkable decrease of blood glucose levels. Taken together, the results indicate that the petroleum ether extract is the major hypoglycemic part in edible Opuntia Milpa Alta, which may be developed to a potential natural hypoglycemic functional ingredient.     

Cytotoxic Alangium alkaloids from Alangium longiflorum

Seven alkaloids (1-7) were isolated from the stem bark of Alangium longiflorum. Compound 1, (-)-10-O-demethylisocephaeline, was isolated for the first time as a naturally occurring product from a plant source. All structures were elucidated by detailed spectroscopic analysis. Biological evaluation showed that 2, 10-O-demethylcephaeline, exhibited potent cytotoxic activity against human lung carcinoma (A549) and breast adenocarcinoma (MCF-7) with ED(50) values of 0.013 and 0.062 microM, respectively. The stereoisomer 1 was less potent than 2, and related compounds with different hydroxy/methoxy substitution patterns were also less potent or inactive. Thus, compound 2 merits attention as a cytotoxic lead for further study.