Potential of Beauveria bassiana (Hyphomycetes: Moniliales) for controlling the white pine weevil, Pissodes strobi (Col., Curculionidae)

Abstract:  Studies were conducted under laboratory conditions to document the potential of Beauveria bassiana conidia applications for controlling the white pine weevil, Pissodes strobi (Peck). A screening test including six B. bassiana isolates allowed us to demonstrate that CFL (Centre de Foresterie des Laurentides) and IP-CPB (Île Perrault-charançon du pin blanc) were the most virulent isolates among the ones tested, with percentages of mortality after 3 weeks of 73% and 85.5%, respectively. These two B. basiana isolates were applied either onto soil or branch sections to compare the effectiveness of these potential control strategies. Greater than 75% mortality was observed within 3 weeks for both modes of application using suspensions of B. bassiana at a concentration of 1.0 × 10⁸ (soil application) and 1.0 × 10⁹ conidia/ml (branch application). The results demonstrate for the first time that B. bassiana is an effective entomopathogen against P. strobi .     

Specific binding of ribosome recycling factor (RRF) with the Escherichia coli ribosomes by BIACORE

The direct assays on Biacore with immobilised RRF and purified L11 from E. coli in the flow trough have shown unspecific binding between the both proteins. The interaction of RRF with GTPase domain of E. coli ribosomes, a functionally active complex of L11 with 23S r RNA and L10.(L7/L12)₄ was studied by Biacore. In the experiments of binding of RRF with 30S, 50S and 70S ribosomes from E. coli were used the antibiotics thiostrepton, tetracycline and neomycin and factors, influencing the 70S dissociation Mg²⁺, NH₄Cl, EDTA. The binding is strongly dependent from the concentrations of RRF, Mg²⁺, NH₄Cl, EDTA and is inhibited by thiostrepton. The effect is most specific for 50S subunits and indicates that the GTPase centre can be considered as a possible site of interaction of RRF with the ribosome. We can consider an electrostatic character of the interactions with most probable candidate 16S and 23S r RNA at the interface of 30S and 50S ribosomal subunits.     

Effect of high concentrations of sucrose on the enzymatic activity of alpha-chymotrypsin

The effect of the low-molecular-mass natural reagents in high concentrations is important for investigating enzymatic reactions in near "in vivo" conditions and for optimisation of biotechnology processes. A model system, including p-nitrophenyl acetate as substrate and alpha-chymotrypsin as proteolytic enzyme, has been used to study the effect of high concentrations of sucrose, both influencing the viscosity of the reaction medium and acting as a nucleophilic effector (activator) on the enzymatic reaction. A kinetic scheme at high concentrations of nucleophilic effectors (sucrose) has been proposed.     

Terpenoids from Achillea setacea

The aerial parts of Achillea setacea afforded, in addition of a rare monoterpene triol and 12 known sesquiterpene lactones, a new guaianolide containing an endoperoxide ring. Its structure was elucidated by spectral methods.     

Sesquiterpene lactones from Anthemis carpatica Willd

Four new eudesmanolides and two new guaianolides were isolated from the aerial parts of Anthemis carpatica Willd. and their structures elucidated by spectral methods. In addition, seven known sesquiterpene lactones were identified.     

Role of the C-terminal chain in human interferongamma stability: an electrostatic study

Electrostatic interactions in two structures of human interferon gamma (hIFNgamma), corresponding to interferon molecule alone and bound to its receptor, were analyzed on the basis of a continuum dielectric model. It was found that a number of titratable groups, mainly basic, show large pK shifts and remain in their neutral forms at physiologically relevant pH. The fact that these groups are largely common to both structures and that most of them belong to the set of most conserved sites suggests that this is a property inherent to the hIFNgamma molecule rather than an artifact of the crystal packing. His111 was also found deprotonated at neutral pH. It was concluded that receptor recognition involving His111 is driven by aromatic coupling of His111 and Tyr52 from the receptor rather than by electrostatic interactions. The structure corresponding to hIFNgamma in complex with its receptor shows a reduction in number and in degree of desolvation of the buried titratable sites. This finding suggested that on receptor binding, hIFNgamma adopts energetically more favorable, relaxed, conformation. It was experimentally shown that in contrast to the full-size hIFNgamma, the construct having 21 amino acid residues deleted from the C-terminus is soluble. The hydrophobicity profile analysis suggested that factors other than the exposure of hydrophobic parts of the molecule are responsible for the low stability and propensity for aggregation. On the basis of these results, it was assumed that the electrostatic influence of the C-terminal part contributes particularly to the low solvent exposure of the titratable groups, and hence to the low structural stability and propensity for aggregation of the recombinant hIFNgamma. Proteins 2001;43:125-133.     

Comparative study of Tanacetum species growing in Bulgaria

Chemical investigation of the Bulgarian species Tanacetum. parthenium, T. millefolium, T. achilleifolium, T. corymbosum and T. macrophyllum afforded in addition to 24 known sesquiterpene lactones a new 12, 8-eudesmanolide 22. Besides, four known highly oxigenated terpenoids and a new keto-diol 30 of the rare iphionane skeleton were also isolated. The structures were elucidated on the basis of their spectral properties. The accumulation of the different sesquiterpene lactones in the studied species and there classification is discussed.     

Social Support and Health in Diabetes Patients: An Observational Study in Six European Countries in an Era of Austerity

Introduction

Support from individual social networks, community organizations and neighborhoods is associated with better self-management and health outcomes. This international study examined the relative impact of different types of support on health and health-related behaviors in patients with type 2 diabetes.

Methods

Observational study (using interviews and questionnaires) in a sample of 1,692 type 2 diabetes patients with 5,433 connections from Bulgaria, Greece, Netherlands, Norway, Spain, and the United Kingdom. Outcomes were patient-reported health status (SF-12), physical exercise (RAPA), diet and smoking (SDCSCA). Random coefficient regression models were used to examine linkages with individual networks, community organizations, and neighborhood type (deprived rural, deprived urban, or affluent urban).

Results

Patients had a median of 3 support connections and 34.6% participated in community organizations. Controlled for patients’ age, sex, education, income and comorbidities, large emotional support networks were associated with decrease of non-smoking (OR = 0.87). Large practical support networks were associated with worse physical and mental health (B = -0.46 and -0.27 respectively) and less physical activity (OR = 0.90). Participation in community organizations was associated with better physical and mental health (B = 1.39 and 1.22, respectively) and, in patients with low income, with more physical activity (OR = 1.53).

Discussion

Participation in community organizations was most consistently related to better health status. Many diabetes patients have individual support networks, but this study did not provide evidence to increase their size as a public health strategy. The consistent association between participation in community organizations and health status provides a clear target for interventions and policies.     

Daunorubicin Derivatives Obtained from Daunorubicin and Nucleoside Dialdehydes

Abstract

Nucleoside dialdehydes were obtained by periodate oxidation of adenosine, cytidine, guanosine, uridine or 6-azauridine in the presence of Dowex (1×8; CH₃COO). Reductive alkylation of daunorubicin with these dialdehydes in the presence of NaBH₃CN produced a series of 3′-deamino-3′-(4-morpholino)daunorubicin or 13-(R, S)-dihydrodaunorubicin derivatives, the latter being mixtures of two diastereomers at 13-C atom. The morpholino-daunorubicin derivatives containing nucleic base moieties are less cytotoxic than cyanomorpholino-daunorubicin, morpholino-daunorubicin and even than the parent antibiotic.