Formulation, process conditions, and biological evaluation of dairy mixed gels containing fava bean and milk proteins: Effect on protein retention in growing young rats.

Food formulation and process conditions can indirectly influence AA digestibility and bioavailability. Here we investigated the effects of formulation and process conditions used in the manufacture of novel blended dairy gels (called "mixed gels" here) containing fava bean (Vicia faba) globular proteins on both protein composition and metabolism when given to young rats. Three mixed dairy gels containing casein micelles and fava bean proteins were produced either by chemical acidification (A) with glucono-δ-lactone (GDL) or by lactic acid fermentation. Fermented gels containing casein and fava bean proteins were produced without (F) or with (FW) whey proteins. The AA composition of mixed gels was evaluated. The electrophoretic patterns of mixed protein gels analyzed by densitometry evidenced heat denaturation and aggregation via disulfide bonds of fava bean 11S legumin that could aggregate upon heating of the mixtures before gelation. Moreover, fermented gels showed no particular protein proteolysis compared with gel obtained by GDL-induced acidification. Kinetics of acidification were also evaluated. The pH decreased rapidly during gelation of GDL-induced acid gel compared with fermented gel. Freeze-dried F, A, and FW mixed gels were then fed to 30 young (1 mo old) male Wistar rats for 21 d (n = 10/diet). Fermented mixed gels significantly increased protein efficiency ratio (+58%) and lean mass (+26%), particularly muscle mass (+9%), and muscle protein content (+15%) compared with GDL-induced acid gel. Furthermore, F and FW formulas led to significantly higher apparent digestibility and true digestibility (+7%) than A formula. Blending fava bean, casein, and whey proteins in the fermented gel FW resulted in 10% higher leucine content and significantly higher protein retention in young rats (+7% and +28%) than the F and A mixed gels, respectively. Based on protein gain in young rats, the fermented fava bean, casein, and whey mixed proteins gel was the most promising candidate for further development of mixed protein gels with enhanced nutritional benefits.

A quality improvement project to increase self-administration of medicines in an acute hospital.

QUALITY PROBLEM OR ISSUE: A patient survey found significantly fewer patients reported they had self-administered their medicines while in hospital (20% of 100 patients) than reported that they would like to (44% of 100). We aimed to make self-administration more easily available to patients who wanted it. INITIAL ASSESSMENT: We conducted a failure, modes and effects analysis, collected baseline data on four wards and carried out observations. CHOICE OF SOLUTION: Our initial assessment suggested that the main areas we should focus on were raising patient awareness of self-administration, changing the patient assessment process and creating a storage solution for medicines being self-administered. We developed new patient information leaflets and posters and a doctor's assessment form using Plan-Do-Study-Act cycles. We developed initial designs for a storage solution. IMPLEMENTATION: We piloted the new materials on three wards; the fourth withdrew due to staff shortages. EVALUATION: Following collection of baseline data, we continued to collect weekly data. We found that the proportion of patients who wished to self-administer who reported that they were able to do so, significantly increased from 41% (of 155 patients) to 66% (of 118 patients) during the study, despite a period when the hospital was over capacity. LESSONS LEARNED: Raising and maintaining healthcare professionals' awareness of self-administration can greatly increase the proportion of patients who wish to self-administer who actually do so. Healthcare professionals prefer multi-disciplinary input into the assessment process.

Understanding the responses of Saccharomyces cerevisiae yeast strain during dehydration processes using synchrotron infrared spectroscopy.

For the first time, synchrotron infrared spectroscopy was performed on yeast during dehydration processes in real time with simultaneously controlled relative humidity and temperature. This led us to investigate the biochemical modification in relation to the dehydration of Saccharomyces cerevisiae. The correlation between the hydration level and yeast survival was observed. Following the test conditions, the modification of the protein structure was observed. However, no evident modification of the lipid composition resulting from dehydration was observed. Furthermore, the results showed that the medium rich in nutrients and glutathione precursors can improve yeast survival during dehydration at 45 °C. This could be related to the high relative amounts of CH3 groups in the lipid composition assigned to the low lipid oxidation level in this case. Our work demonstrated the feasibility of using S-FTIR for investigating yeast responses to dehydration processes in real time. This method can be used for understanding the effect of dehydration/rehydration on the biochemical modification of yeast.

Predicting energy x protein interaction on milk yield and milk composition in dairy cows.

Feed management is one of the principal levers by which the production and composition of milk by dairy cows can be modulated in the short term. The response of milk yield and milk composition to variations in either energy or protein supplies is well known. However, in practice, dietary supplies of energy and protein vary simultaneously, and their interaction is still not well understood. The objective of this trial was to determine whether energy and protein interacted in their effects on milk production and milk composition and whether the response to changes in the diets depended on the parity and potential production of cows. From the results, a model was built to predict the response of milk yield and milk composition to simultaneous variations in energy and protein supplies relative to requirements of cows. Nine treatments, defined by their energy and protein supplies, were applied to 48 cows divided into 4 homogeneous groups (primiparous or multiparous x high or low milk potential) over three 4-wk periods. The control treatment was calculated to cover the predicted requirements of the group of cows in the middle of the trial and was applied to each cow. The other 8 treatments corresponded to fixed supplies of energy and protein, higher or lower than those of the control treatment. The results highlighted a significant energy x protein interaction not only on milk yield but also on protein content and yield. The response of milk yield to energy supply was zero with a negative protein balance and increased with protein supply equal to or higher than requirements. The response of milk yield to changes in the diet was greater for cows with high production potential than for those with low production potential, and the response of milk protein content was higher for primiparous cows than for multiparous cows. The model for the response of milk yield, protein yield, and protein content obtained in this trial made it possible to predict more accurately the variations in production and composition of milk relative to the potential of the cow because of changes in diet composition. In addition, the interaction obtained was in line with a response corresponding to the more limiting of 2 factors: energy or protein.

Defining the user role in infection control.

BACKGROUND: Health policy initiatives continue to recognize the valuable role of patients and the public in improving safety, advocating the availability of information as well as involvement at the point of care. In infection control, there is a limited understanding of how users interpret the plethora of publicly available information about hospital performance, and little evidence to support strategies that include reminding healthcare staff to adhere to hand hygiene practices. AIM: To understand how users define their own role in patient safety, specifically in infection control. METHODS: Through group interviews, self-completed questionnaires and scenario evaluation, user views of 41 participants (15 carers and 26 patients with recent experience of inpatient hospital care in London, UK) were collected and analysed. In addition, the project's patient representative performed direct observation of the research event to offer inter-rater reliability of the qualitative analysis. FINDINGS: Users considered evidence of systemic safety-related failings when presented with hospital choices, and did not discount hospitals with high ('red' flagged) rates of meticillin-resistant Staphylococcus aureus. Further, users considered staff satisfaction within the workplace over and above user satisfaction. Those most dissatisfied with the care they received were unlikely to ask staff, 'Have you washed your hands?' CONCLUSION: This in-depth qualitative analysis of views from a relatively informed user sample shows 'what matters', and provides new avenues for improvement initiatives. It is encouraging that users appear to take a holistic view of indicators. There is a need for strategies to improve dimensions of staff satisfaction, along with understanding the implications of patient satisfaction.

Lay involvement in the analysis of qualitative data in health services research: a descriptive study.

PLAIN ENGLISH SUMMARY: There is a consensus that patients and the public should be involved in research in a meaningful way. However, to date, lay people have been mostly involved in developing research ideas and commenting on patient information.We previously published a paper describing our experience with lay partners conducting observations in a study of how patients in hospital are involved with their medicines. In a later part of the same study, lay partners were also involved in analysing interviews that a researcher had conducted with patients, carers and healthcare professionals about patient and carer involvement with medicines in hospital. We therefore wanted to build on our previous paper and report on our experiences with lay partners helping to conduct data analysis. We therefore interviewed the lay members and researchers involved in the analysis to find out their views.Both lay members and researchers reported that lay partners added value to the study by bringing their own perspectives and identifying further areas for the researcher to look for in the interviews. In this way researchers and lay partners were able to work together to produce a richer analysis than would have been possible from either alone. ABSTRACT: Background It is recognised that involving lay people in research in a meaningful rather than tokenistic way is both important and challenging. In this paper, we contribute to this debate by describing our experiences of lay involvement in data analysis.Methods We conducted semi-structured interviews with the lay partners and researchers involved in qualitative data analysis in a wider study of inpatient involvement in medication safety. The interviews were transcribed verbatim and coded using open thematic analysis.Results We interviewed three lay partners and the three researchers involved. These interviews demonstrated that the lay members added value to the analysis by bringing their own perspectives; these were systematically integrated into the analysis by the lead researcher to create a synergistic output. Some challenges arose, including difficulties in recruiting a diverse range of members of the public to carry out the role; however there were generally fewer challenges in data analysis than there had been with our previous experience of lay partners' involvement in data collection.Conclusions Lay members can add value to health services research by being involved in qualitative data analysis.

Binding of carotenoids on reaction centers from Rhodopseudomonas sphaeroides R 26.

The carotenoid-less reaction centers isolated from Rhodopseudomonas sphaeroides (strain R 26) bind pure all-trans spheroidene as well as spheroidenone in a nearly 1 : 1 molar ratio with respect to P-870. Neither beta-carotene nor spirilloxanthin, both absent from wild-type Rps. sphaeroides, could be bound in appreciable amounts. Resonance Raman spectra of the carotenoid-reaction center complex indicate that the carotenoid is bound as a cis isomer, its conformation being very close, although probably not identical, to that assumed by the carotenoid in the wild-type reaction centers. The electronic absorption spectra of the carotenoid-reaction center complexes are in good agreement with such a interpretation. When bound to the R 26 reaction centers, spheroidene displays light-induced absorbance changes identical in peak wavelengths and comparable in amplitudes to those observed in the wild-type reaction centers. Thus the binding of the carotenoid to the R 26 reaction centers most likely occurs at the same proteic site as in the wild-type reaction centers. This site shows selectivity towards the nature of carotenoids, and has the same sterical requirement as in the wild type, leading to the observed all-trans to cis isomerisation.

On the state of carotenoids bound to reaction centers of photosynthetic bacteria: a resonance Raman study.

The carotenoids bound to reaction centers of wild, Ga and GIC strains of Rhodopseudomonas spheroides, of Rhodospirrillum rubrum, strain S1 and of Rhodopseudomonas viridis, yield very similar, but unusual resonance Raman spectra. Through a comparison with resonance Raman spectra of 15,15'-cis-beta-carotene, these carotenoids are shown to assume cis conformations, while the corresponding chromatophores contain all-trans forms only. These cis conformations likely are identical for all the carotenoids studied. They remain unaffected by variations of temperature from 20 to 300 K as well as by the redox state of P-870. They are unstable, being rapidly isomerised towards the all-trans forms when extracted from the reaction centers. The possible nature of these conformers is discussed on the basis of their electronic and vibrational spectra.

Two-dimensional structure of the native light-harvesting complex LH2 from Rubrivivax gelatinosus and of a truncated form.

The light-harvesting complex LH2 of Rubrivivax gelatinosus has an oligomeric structure built from alpha-beta heterodimers containing three bacteriochlorophylls and one carotenoid each. The alpha subunit (71 residues) presents a C-terminal hydrophobic extension (residues 51-71) which is prone to attack by an endogenous protease. This extension can also be cleaved by a mild thermolysin treatment, as demonstrated by electrophoresis and by matrix-assisted laser desorption-time of flight mass spectrometry. This cleavage does not affect the pigment binding sites as shown by absorption spectroscopy. Electron microscopy was used to investigate the structures of the native and thermolysin cleaved forms of the complexes. Two-dimensional crystals of the reconstituted complexes were examined after negative staining and cryomicroscopy. Projection maps at 10 A resolution were calculated, demonstrating the nonameric ring-like organization of alpha-beta subunits. The cleaved form presents the same structural features. We conclude that the LH2 complex is structurally homologous to the Rhodopseudomonas acidophila LH2. The hydrophobic C-terminal extension does not fold back in the membrane, but lays out on the periplasmic surface of the complex.

Preliminary characterization by X-ray diffraction of crystals of photochemical reaction centres from wild-type Rhodopseudomonas spheroides.

Reaction centres from wild-type Rhodopseudomonas spheroides (strain Y) in a solution of octylglucoside have been crystallized with polyethylene glycol as precipitant, either by vapour diffusion or dialysis. Orthorhombic crystals (space group P2(1)2(1)2(1)) diffract to 3.5 A resolution. The unit cell parameters are a = 142.5 A, b = 141.5 A, c = 80 A; they are compatible with the presence of one reaction centre per asymmetric unit.

A specific carotenoid is required for reconstitution of the Rubrivivax gelatinosus B875 light harvesting complex from its subunit form B820.

The core light-harvesting complex B875 from Rubrivivax gelatinosus has been reconstituted from its subunit form B820 with hydroxyspheroidene, the carotenoid which is bound to native B875 antenna. Other carotenoids which are chemically similar to hydroxyspheroidene (spheroidene, spheroidenone, neurosporene and spirilloxanthin) gave only low levels of partial reconstitution. Absorption and circular dichroism spectra of the hydroxyspheroidene-containing, reconstituted B875 were identical with those of original B875 antenna isolated directly from chromatophores, indicating that the two hydroxyspheroidene molecules bind to their native sites within the (alpha beta)Bchl2 subunit during the reconstitution process. These observations point to a structural role for this carotenoid in determining the architecture of Rv. gelatinosus B875 antenna.

Solubility diagram of the Rhodobacter sphaeroides reaction center as a function of PEG concentration.

In order to quantify the effect of polyethylene glycol 4000 (PEG) on the solubility of an integral membrane protein, we have crystallized the photochemical reaction center from Rhodobacter sphaeroides Y by batch method on a large range of PEG. The measurement of the solubility diagram display a semi-logarithmic dependence of solubility versus PEG concentration. Comparison of our results with previously published ones [Odahara, T., Ataka, M. and Katsura, M. (1994) Acta Cryst. D50, 639-642] suggests a notable effect of additional 1,2,3-heptane-triol and/or temperature on photochemical reaction center solubility.

Structure of spheroidene in the photosynthetic reaction center from Y Rhodobacter sphaeroides.

The structure of the reaction center of Y Rhodobacter sphaeroides has been solved at 3 A resolution, using the atomic coordinates of the reaction center from the carotenoidless mutant R26 Rhodobacter sphaeroides. The structure has been refined by a stimulated annealing with the computer program X-PLOR, leading to a crystallographic R factor of 0.22 using reflections between 8 and 3 A. The spheroidene molecule which is bound to the Y reaction center has been fitted in the electron density map as a 15-cis isomer with a highly asymmetric structure. The cis-bond is located at proximity from ring 1 of the accessory bacteriochlorophyll on the inactive M side. The nature of the cis-bond was confirmed by resonance Raman spectra obtained from Y reaction center crystals. The structure of spheroidene in Y reaction center is compared to that proposed for 1,2-dihydroneurosporene in Rhodopseudomonas viridis reaction center crystals.

Towards the understanding of the function of Rb sphaeroides Y wild type reaction center: gene cloning, protein and detergent structures in the three-dimensional crystals.

We report various experiments aimed at the resolution of the 3-dimensional structure of the photosynthetic reaction center from wild type Y Rhodobacter sphaeroides. The genes encoding the L and M polypeptides have been cloned and sequenced. They bear 2 mutations each when compared to those already sequenced in another Rb sphaeroides strain (2.4.1). In the L gene, these codon changes are silent. In the M gene, one is silent and the other one leads to a Leu-Met substitution at position 140. At the present stage of the refinement of the X-ray data (0.3 nm resolution) the structure of the Y reaction center is shown to be highly similar to that of the Rhodopseudomonas viridis reaction center. The binding of spheroidene on the M side of the Y reaction center is shown to be determined by hydrophobic interactions with neighboring amino acids and by steric factors. Preliminary results concerning the localization of the detergent (beta-octylglucoside) in the unit cell are presented. This method combines low angle neutron scattering at different contrasts in H2O/D2O with X-ray crystallographic data.

Thickness measurements of single walled dimyristoyl phosphatidylcholine vesicles by neutron scattering.

A method of deriving by neutron scattering thicknesses of lamellae in suspensions has been applied to single-walled vesicles of dimyristoyl phosphatidylcholine. The contrast variation method, based on data obtained for a range of isotope mixtures, has been used to extract a dimension Dw related to the lipid bilayer thickness and a measure alpha of the difference of density within the lamellae. Isotope mixtures for the lipid were used to optimize the information available. Dw is compared with results from multilayer stacks of lipid layers. The thickness for the low temperature L beta, structure has been observed to be higher than for the high temperature L alpha structure. Preliminary experiments on the kinetics of the mixing of the lipid isotope species are reported, and evidence is shown that the species are not segregated for lipids either above or below the transition temperature.

Detection of early gamma-postirradiation effects in murine spleen by proton NMR relaxation times.

BACKGROUND: It was our aim to evaluate the potential of proton relaxation times for the early detection of radiation-induced spleen changes. MATERIALS AND METHODS: Female Swiss mice were irradiated with doses ranging from 0.05 Gy to 4 Gy. The body weight, the spleen weight and the spleen water content of single animals were determined. Measurements of longitudinal (T1) and transversal (T2) proton relaxation times of the spleen samples were performed in a 0.47 T spectrometer. Histological examinations of the control and irradiated organs were performed. RESULTS: NMR measurements during the first five days after irradiation showed that total body gamma-irradiation with doses from 1.5 Gy to 4 Gy results in decreasing T1 of the murine spleen. Significant shortening in T2 was observed for the spleen of animals irradiated with a dose of 4 Gy. Histological examinations demonstrated subnormal architecture in slices derived from animals irradiated with 2 Gy and 4 Gy. CONCLUSION: The fluctuations of the spleen T1 and T2 of irradiated mice are correlated with relative spleen weight and can be used to estimate radiation induced changes in this organ.

Purification of hydroperoxide lyase from green bell pepper (Capsicum annuum L.) fruits for the generation of C6-aldehydes in vitro.

The aim of this work was to compare the efficiency of different extracts of hydroperoxide lyase from green bell peppers in producing aldehydes: a crude extract, a chloroplastic fraction, and a purified enzyme were investigated. From a crude extract, the HPO lyase was purified by ion-exchange chromatography with a 22.3-fold increase in purification factor. Analysis by SDS-PAGE electrophoresis under denaturating conditions showed only one protein with a molecular weight of 55 kDa, whereas size-exclusion chromatography indicated a molecular weight of 170 kDa. A maximum of 7500 mg of aldehydes per g of protein was obtained with the purified enzyme within 20 min of bioconversion compared to 392 and 88 mg of aldehydes per g of protein within 50 and 60 min, respectively, for the chloroplast fraction and the crude extract.

[Intensity modulation in breast radiotherapy: development of an innovative field-in-field technique at Institut Gustave-Roussy]. / Modulation d'intensité en radiothérapie mammaire : développement d'une méthode innovante de champ dans le champ à l'institut Gustave-Roussy.

PURPOSE: To assess the potential dosimetric gain of presegmentation modulated radiotherapy (OAPS, DosiSoft™) of breast, compared to routine 3D conformal radiotherapy. PATIENTS AND METHODS: Twenty patients treated with conservative surgery for breast cancer (9 right and 11 left sided) with various breast volume (median 537 cm(3); range [100-1049 cm(3)]) have been selected. For each patient, we have delineated a breast volume and a compensation volume (target volumes), as well as organs at risk (lungs and heart). Two treatment plans have been generated: one using the routine 3D conformal technique and the other with the presegmentation algorithm of DosiSoft™ (OAPS). The dose distribution were analyzed using the conformity index for target volumes, mean dose and V30 Gy for the heart, and mean dose, V20 Gy and V30 Gy for lungs. RESULTS: Over the 20 patients, the conformity index increased from 0.897 with routine technique to 0.978 with OAPS (P<0,0001). For heart and lung, OAPS decreased irradiation (mean cardiac dose 1,3 vs 1,6 Gy [P<0,0001] and pulmonary V20 Gy 6,6 vs 7,1 [P<0,0001]). CONCLUSION: OAPS (DosiSoft™) is an original method of segmentation of breast. It is automatic, fast and easy, and is able to increase the conformity index, while sparing organ at risk.