Relationships between wild bees,hoverflies and pollination success in apple orchards with different landscape contexts

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Synthesis and in vitro pharmacological evaluation of N-[(1-benzyl-1,2,3-triazol-4-yl)methyl]-carboxamides on d-secoestrone scaffolds

An efficient synthesis of several N-[(1-benzyl-1,2,3-triazol-4-yl)methyl]carboxamides in the 13β- and 13α-d-secoestrone series is reported. Novel triazoles were synthesized via the Cu(I)-catalyzed azide–alkyne cycloaddition of steroidal alkynyl carboxamides and p-substituted benzyl azides. Each of the products was evaluated in vitro by means of MTT assays for antiproliferative activity against a panel of human adherent cancer cell lines (HeLa, MCF-7, A431 and A2780). Some of them exhibited activities similar to those of the reference agent cisplatin. On change of the substitution pattern of the benzyl group of the azide, great differences in the cell growth-inhibitory properties were observed. The p-alkylbenzyl-substituted triazoles selectively exerted high cytostatic action against A2780 cells, with IC₅₀ values of 1?µM. We investigated the potential inhibitory action exerted on the human 17β-HSD1 activity of the new secosteroids. Three triazoles effectively suppressed the estrone to 17β-estradiol conversion with IC₅₀ values in low micromolar range.     

A new glycosidation method through nitrite displacement on substituted nitrobenzenes

Benzyl, benzoyl, and acetyl protected 1-OH and 1-SH glycoses in the glucose, glucosamine, galactose, mannose, and lactose series react with nitrobenzenes activated by one or two electron withdrawing substituents like nitro and cyano to afford the corresponding aryl glycosides in 50-100% yield. The S(N)Ar displacement of nitrite by 1-OH glycoses is reversible and gives predominantly the alpha-glycosides, whereas 1-SH glycoses do not anomerize and afford the beta-glycosides. Thus, the prepared dicyanophenyl gycosides are useful building blocks for the preparation of phthalocyanine-glycoconjugates via template synthesis.     

C1 inhibitor serpin domain structure reveals the likely mechanism of heparin potentiation and conformational disease

C1 inhibitor, a member of the serpin family, is a major down-regulator of inflammatory processes in blood. Genetic deficiency of C1 inhibitor results in hereditary angioedema, a dominantly inheritable, potentially lethal disease. Here we report the first crystal structure of the serpin domain of human C1 inhibitor, representing a previously unreported latent form, which explains functional consequences of several naturally occurring mutations, two of which are discussed in detail. The presented structure displays a novel conformation with a seven-stranded beta-sheet A. The unique conformation of the C-terminal six residues suggests its potential role as a barrier in the active-latent transition. On the basis of surface charge pattern, heparin affinity measurements, and docking of a heparin disaccharide, a heparin binding site is proposed in the contact area of the serpin-proteinase encounter complex. We show how polyanions change the activity of the C1 inhibitor by a novel "sandwich" mechanism, explaining earlier reaction kinetic and mutagenesis studies. These results may help to improve therapeutic C1 inhibitor preparations used in the treatment of hereditary angioedema, organ transplant rejection, and heart attack.     

Gene expression dynamics in deer antler: mesenchymal differentiation toward chondrogenesis

Annual re-growth of deer antler represents a unique example of complete organ regeneration. Because antler mesenchymal cells retain their embryonic capacity to develop into cartilage or bone, studying antler development provides a natural system to follow gene expression changes during mesenchymal differentiation toward chondrogenic/osteogenic lineage. To identify novel genes involved either in early events of mesenchymal cell specialization or in robust bone development, we have introduced a 3 K heterologous microarray set-up (deer cDNA versus mouse template). Fifteen genes were differentially expressed; genes for housekeeping, regulatory functions (components of different signaling pathways, including FGF, TGFβ, Wnt), and genes encoding members of the Polycomb group were represented. Expression dynamics for genes are visualized by an expression logo. The expression profile of the gene C21orf70 of unknown function is described along with the effects when over-expressed; furthermore the nuclear localization of the cognate protein is shown. In this report, we demonstrate the particular advantage of the velvet antler model in bone research for: (1) identification of mesenchymal and precartilaginous genes and (2) targeting genes upregulated in robust cartilage development. Electronic supplementary material Supplementary material is available in the online version of this article at and is accessible for authorized users.     

Synthesis, characterization and biological evaluation of some novel 17-isoxazoles in the estrone series

Regioselective 1,3-dipolar cycloadditions of different aryl nitrile oxides to mestranol were carried out to furnish novel steroidal 17α-isoxazoles in good to excellent yields. Copper(I) was found to be an efficient catalyst, accelerating the intermolecular ring-closures and leading exclusively to 3,5-disubstituted isoxazoles. The yields of the cycloadducts, however, were influenced by the substituents on the aromatic moiety of the 1,3-dipoles. Moreover, dehydration of the primary products resulted in the corresponding Δ(16,17)exo-heterocyclic derivatives. All the synthesized compounds were subjected to in vitro pharmacological studies of their antiproliferative effects relative to three human malignant cell lines (HeLa, MCF7 and A2780).     

Formulation development of the biocontrol agent Bacillus subtilis strain CPA-8 by spray-drying

Aims: To prepare commercially acceptable formulations of Bacillus subtilis CPA‐8 by spray‐drying with long storage life and retained efficacy to control peach and nectarine brown rot caused by Monilinia spp. Methods and Results: CPA‐8 24‐h‐ and 72‐h‐old cultures were spray dried using 10% skimmed milk, 10% skimmed milk plus 10% MgSO₄, 10% MgSO₄ and 20% MgSO₄ as carriers/protectants. All carriers/protectants gave good percentages of powder recovery (28–38%) and moisture content (7–13%). CPA‐8 survival varied considerably among spray‐dried 24‐h‐ and 72‐h‐old cultures. Seventy‐two hours culture spray dried formulations showed the highest survival (28–32%) with final concentration products of 1·6–3·3 × 10⁹ CFU g^?1, while viability of 24‐h‐old formulations was lower than 1%. Spray‐dried 72‐h‐old formulations were selected to subsequent evaluation. Rehydration of cells with water provided a good recovery of CPA‐8 dried cells, similar to other complex rehydration media tested. Spray‐dried formulations stored at 4 ± 1 and 20 ± 1°C showed good shelf life during 6 months, and viability was maintained or slightly decreased by 0·2–0·3‐log. CPA‐8 formulations after 4‐ and 6 months storage were effective in controlling brown rot caused by Monilinia spp. on nectarines and peaches resulting in a 90–100% reduction in disease incidence. Conclusions: Stable and effective formulations of biocontrol agent B. subtilis CPA‐8 could be obtained by spray‐drying. Significance and Impact of the Study: New shelf‐stable and effective formulations of a biocontrol agent have been obtained by spray‐drying to control brown rot on peach.     

Association between Ω3 and Ω6 fatty acid intakes and serum inflammatory markers in COPD

Dietary intake of polyunsaturated fatty acids, including omega-3 and omega-6, could modulate chronic obstructive pulmonary disease (COPD) persistent inflammation. We aimed to assess the relationship between dietary intake of omega-3 and omega-6 fatty acids and serum inflammatory markers in COPD. A total of 250 clinically stable COPD patients were included. Dietary data of the last 2 years were assessed using a validated food frequency questionnaire (122 items), which provided levels of three omega-3 fatty acids: docosahexaenoic acid, eicosapentaenoic acid and α-linolenic acid (ALA); and two omega-6 fatty acids: linoleic acid and arachidonic acid (AA). Inflammatory markers [C-reactive protein (CRP), interleukin (IL)-6, IL-8 and tumor necrosis factor alpha (TNFα)] were measured in serum. Fatty acids and inflammatory markers were dichotomised according to their median values, and their association was assessed using multivariate logistic regression. Higher intake of ALA (an anti-inflammatory omega-3 fatty acid) was associated with lower TNFα concentrations [adjusted odds ratio (OR)=0.46; P=.049]. Higher AA intake (a proinflammatory omega-6 fatty acid) was related to higher IL-6 (OR=1.96; P=.034) and CRP (OR=1.95; P=.039) concentrations. Therefore, this study provides the first evidence of an association between dietary intake of omega-3 and omega-6 fatty acids and serum inflammatory markers in COPD patients.     

Selected anthropometric variables and aerobic fitness as predictors of cardiovascular disease risk in children

The aim of this study was to assess the suitability of body mass index, waist circumference, waist-to-height ratio and aerobic fitness as predictors of cardiovascular risk factor clustering in children. A cross-sectional study was conducted with 290 school boys and girls from 6 to 10 years old, randomly selected. Blood was collected after a 12-hour fasting period. Blood pressure, waist circumference (WC), height and weight were evaluated according to international standards. Aerobic fitness (AF) was assessed by the 20-metre shuttle-run test. Clustering was considered when three of these factors were present: high systolic or diastolic blood pressure, high low-density lipoprotein (LDL) cholesterol, high triglycerides, high plasma glucose, high insulin concentrations and low high-density lipoprotein (HDL) cholesterol. A ROC curve identified the cut-off points of body mass index (BMI), WC, waist-to-height ratio (WHtR) and AF as predictors of risk factor clustering. BMI, WC and WHR resulted in significant areas under the ROC curves, which was not observed for AF. The anthropometric variables were good predictors of cardiovascular risk factor clustering in both sexes, whereas aerobic fitness should not be used to identify cardiovascular risk factor clustering in these children.