Development of the BELANA questionnaire for the analysis of economic burdens of food allergy and intolerance.

INTRODUCTION: Patients affected by food allergies and intolerance need to apply dedicated avoidance strategies and also prevent the consequences of unbalanced diets. In most countries, the health economic costs for these patients are unknown. METHODS: To measure temporal and financial burdens of the patients in multinational settings, the BELANA questionnaire (Burdens and Expenses of Living as an Adult with Nutrition based Allergy or Intolerance) has been developed. For the complementary measurement of Health Related Quality of Life (HR-QoL), a combined appliance of the disease-specific FAQLQ-AF (Food Allergy Quality of Life Questionnaire - Adult Form) and the generic SF-12v1 (Short Form-12 Health Survey) has been chosen. RESULTS: BELANA collects six economic items while avoiding questions, which are already included in the HR-QoL questionnaires or could lead to denial tendencies. In a web-based pilot survey with 51 patients, the practicability of using BELANA together with the complementary quality of life instruments was investigated. The electronic data collection offers real time plausibility checks and limits the workload for completion and data evaluation. DISCUSSION: The response rates at BELANA health-economic items (76 - 100%) and the high amount of completed questionnaires (50 of 51) confirm the patients acceptance of the chosen methodology. Within the web-based survey, the combination of BELANA, FAQLQ-AF and SF-12v1 was completed in an average of 22 minutes. An age-related selection bias was not been confirmed in this pilot application. The median age in the pilot trial was 37.9 years (minimum age to participate was 18 years, range from 19 to 72 years, Standard Deviation (SD) = 12.4 years). Most of the participants were female (44 of 50). CONCLUSION: It is assumed that the BELANA questionnaire should be a useful tool for the evaluation of health-economic burden for patients with food allergy and intolerance.

Identification and characterisation of lactobacilli isolated from Kimere, a spontaneously fermented pearl millet dough from Mbeere, Kenya (East Africa).

The objective of the study was to isolate potential probiotic lactobacilli from Kimere, a pearl millet dough prepared in the Mbeere community of Kenya, East Africa, by fermentation for 18-24 hours. Kimere samples, collected from 11 different homesteads in Mbeere, showed average pH values of 3.63±0.29. Counts of presumptive lactobacilli were 8.52±0.02 log10 colony forming units per gram, respectively. 48 presumptive Lactobacillus isolates were characterised and identified by biochemical and molecular methods. Lactobacillus fermentum (46 isolates) was the dominant Lactobacillus species detected. Analysis of strain diversity with pulsed-field gel electrophoresis indicated relatively large biodiversity among L. fermentum isolates. All L. fermentum isolates were able to grow in MRS medium containing 0.3% ox gall. Twelve of them were able to grow in the presence of 3% ox gall, and of these 60% survived incubation at pH 3 in the presence of 2 mg pepsin per ml for three hours.

Olefin epoxidation by molybdenum and rhenium peroxo and hydroperoxo compounds: a density functional study of energetics and mechanisms.

A density functional study on olefin epoxidation by rhenium and molybdenum peroxo complexes has been carried out. Various intermediates and transition structures of the systems CH3ReO3/H2O2, H3NMoO3/H2O2, and H3NOMoO3/H2O2 were characterized, including ligated and unligated mono- and bisperoxo intermediates as well as hydroperoxo derivatives. For the rhenium system the bisperoxo complex CH3ReO(O2)2*H2O was found to be most stable and the one with the lowest transition state for epoxidation of ethylene (activation barrier of 16.2 kcal/mol), in line with experimental findings. However, participation of monoperoxo and hydroperoxo complexes in olefin epoxidation cannot be excluded. For both molybdenum systems, hydroperoxo species with an additional ammonia model ligand in axial position were calculated to be most stable. Inspection of calculated activation barriers of ethylene epoxidation reveals that, in both molybdenum systems, hydroperoxo mechanisms are competitive if not superior to peroxo mechanisms. The reaction barriers of the various oxygen transfer processes can be rationalized by structural, orbital, and charge characteristics, exploiting a model that interprets the electrophilic nature of the reactive oxygen center.

[2+3] Cycloaddition of ethylene to transition metal oxo compounds. analysis of density functional results by marcus theory.

Density functional results on the [2+3] cycloaddition of ethylene to various transition metal complexes MO(3)(q) and LMO(3)(q) (q = -1, 0, 1) with M = Mo, W, Mn, Tc, Re, and Os and various ligands L = Cp, CH(3), Cl, and O show that the corresponding activation barriers DeltaE(double dagger) depend in quadratic fashion on the reaction energies DeltaE(0) as predicted by Marcus theory. A thermoneutral reaction is characterized by the intrinsic reaction barrier DeltaE(0) of 25.1 kcal/mol. Both ethylene [2+3] cycloaddition to an oxo complex and the corresponding homolytic M-O bond dissociation are controlled by the reducibility of the transition metal center. Indeed, from the easily calculated M-O bond dissociation energy of the oxo complex one can predict the reaction energy DeltaE(0) and hence, by Marcus theory, the corresponding activation barrier DeltaE. This allows a systematic representation of more than 25 barriers of [2+3] cycloaddition reactions that range from 5 to 70 kcal/mol.

Allylic alcohol epoxidation by methyltrioxorhenium: a density functional study on the mechanism and the role of hydrogen bonding.

By locating all relevant transition structures with a hybrid density functional method, we explored the three most reasonable mechanisms for H2O2 epoxidation of propenol catalyzed by methyltrioxorhenium (MTO), namely: (i) coordination of propenol as lone pair donor to rhenium mono- and bis-peroxo complexes followed by intramolecular epoxidation, (ii) formation of a metal alcoholate, derived from addition of propenol to the Re complex with the formation of a metal-OR bond, followed by intramolecular epoxidation, (iii) intermolecular oxygen transfer assisted by hydrogen bonding where the rhenium complex acts as hydrogen bond acceptor and HOR as hydrogen bond donor. The computational results demonstrate that the last route is highly favored over the other two and, in particular, they provide the first unambiguous and compelling evidence that alcoholate-metal complexes, mechanism (ii), do not appreciably contribute to product formation. In keeping with experimental findings, theoretical data predict that the monoperoxo Re complex should be considerably less reactive than its bis(peroxo) counterpart and suggest that the hydrated form of the latter complex should be the actual active epoxidant species. All transition structures exhibit a distorted spiro-like structure, while the most stable ones feature hydrogen bonding to the attacking peroxo fragment with the olefinic OH group either in an "outside" (OC1C2C3 approximately 128 degrees ) or "inside" (OC1C2C3 approximately 14 degrees ) conformation. Previous qualitative models for transition structures of Re-catalyzed epoxidation of allylic alcohols are discussed in the light of our computational data.

Olefin epoxidation by peroxo complexes of cr, mo, and W. A comparative density functional study

The epoxidation of olefins by peroxo complexes of Cr(VI), Mo(VI) and W(VI) was investigated using the B3LYP hybrid density functional method. For the mono- and bisperoxo model complexes with the structures (NH(3))(L)M(O)(2)(-)(n)()(eta(2)-O(2))(1+)(n)() (n = 0, 1; L = none, NH(3); M = Cr, Mo, W) and ethylene as model olefin, two reaction mechanism were considered, direct oxygen transfer and a two-step insertion into the metal-peroxo bond. The calculations reveal that direct attack of the nucleophilic olefin on an electrophilic peroxo oxygen center via a transition state of spiro structure is preferred as significantly higher activation barriers were calculated for the insertion mechanism than for the direct mechanism. W complexes are the most active in the series investigated with the calculated activation barriers of direct oxygen transfer to ethylene decreasing in the order Cr > Mo > W. Barriers of bisperoxo species are lower than those of the corresponding monoperoxo species. Coordination of a second NH(3) base ligand to the mono-coordinated species, (NH(3))M(O)(2)(eta(2)-O(2)) and (NH(3))MO(eta(2)-O(2))(2), results in a significant increase of the activation barrier which deactivates the complex. Finally, based on a molecular orbital analysis, we discuss factors that govern the activity of the metal peroxo group M(eta(2)-O(2)), in particular the role of metal center.