Three Candidate Probiotic Strains Impact Gut Microbiota and Induce Anergy in Mice with Cow's Milk Allergy.

Cow's milk allergy is a worldwide public health issue, especially since there is no effective treatment, apart from milk and dairy product avoidance. The aim of this study was to assess the beneficial role of three probiotic strains previously selected for their prophylactic properties in a mouse model of ß-lactoglobulin allergy. Administration of Lactobacillus rhamnosus LA305, L. salivarius LA307, or Bifidobacterium longum subsp. infantis LA308 for 3 weeks post-sensitization and challenge modified the composition of the gut microbiota, with an increase in the Prevotella NK3B31 group and a decrease in Marvinbryantia, belonging to the Lachnospiraceae family. Although no impact on markers of sensitization was detected, modifications of foxp3, tgfß, and il10 ileal gene expression, as well as plasma metabolomic alterations in the tryptophan pathway, were observed. Moreover, ex vivo studies showed that all probiotic strains induced significant decreases in cytokine production by ß-lactoglobulin-stimulated splenocytes. Taken together, these results suggest that the three probiotic strains tested lead to alterations in immune responses, i.e., induction of a tolerogenic anergy and anti-inflammatory responses. This anergy could be linked to cecal microbiota modifications, although no impact on fecal short-chain fatty acid (SCFA) concentrations was detected. Anergy could also be linked to a direct impact of probiotic strains on dendritic cells, since costimulatory molecule expression was decreased following coincubation of these strains with bone marrow-derived dendritic cells (BMDCs). To conclude, all three candidate probiotic strains induced strain-specific gut microbiota and metabolic changes, which could potentially be beneficial for general health, as well as anergy, which could contribute to oral tolerance acquisition.IMPORTANCE We showed previously that three probiotic strains, i.e., Lactobacillus rhamnosus LA305, L. salivarius LA307, and Bifidobacterium longum subsp. infantis LA308, exerted different preventive effects in a mouse model of cow's milk allergy. In this study, we evaluated their potential benefits in a curative mouse model of cow's milk allergy. When administered for 3 weeks after the sensitization process and a first allergic reaction, none of the strains modified the levels of sensitization and allergic markers. However, all three strains affected gut bacterium communities and modified immune and inflammatory responses, leading to a tolerogenic profile. Interestingly, all three strains exerted a direct effect on dendritic cells, which are known to play a major role in food sensitization through their potentially tolerogenic properties and anergic responses. Taken together, these data indicate a potentially beneficial role of the probiotic strains tested in this model of cow's milk allergy with regard to tolerance acquisition.

Intestinal permeability and fecal eosinophil-derived neurotoxin are the best diagnosis tools for digestive non-IgE-mediated cow's milk allergy in toddlers.

BACKGROUND: Food allergy is a common problem in France involving 4%-6% of toddlers. As opposed to IgE-mediated cow's milk allergy (CMA), delayed-onset CMA, mostly, non-IgE-mediated, remains difficult to diagnose in toddlers. Our study assessed the diagnostic performances of intestinal permeability and of fecal markers, in comparison with the standard allergic work-up in children referred for CMA diagnosis. METHODS: Twenty-five consecutive children, mean age (standard deviation) 6.3 months (4.8) with digestive and/or extra-digestive manifestations suggesting CMA, were prospectively studied based on a standardized allergic work-up (specific cow's protein IgE and IgG, skin prick test, atopy patch test and oral open cow's milk challenge) and digestive work-up including fecal microbiota analysis, intestinal permeability determination (urinary lactitol/mannitol ratio) and fecal markers measurement, i.e., α(1)-antitrypsin, tumor necrosis factor-α, calprotectin, ß-defensin2, secretory IgA and eosinophil-derived neurotoxin (EDN). Receiver operating characteristic (ROC) curves were calculated for all markers in order to define cut-off levels. RESULTS: The cow's milk challenge was positive in 11 children and negative in 14. The global test performances, i.e., the number of true positive+negative cases/the total number of cases, were 76% for intestinal permeability; 72% for fecal EDN; contrasting with atopy patch test, 68%; IgE, 60%; skin prick test, 55% and IgG, 52%. CONCLUSIONS: In this routine diagnosis allergy work-up for CMA in toddlers, the best efficacy was seen for intestinal permeability compared to IgE, IgG, skin prick test and atopy patch test. Moreover, fecal EDN in a single spot sample displayed a similar performance.

Photosensitizers incorporation in SOPC films at different hydration levels.

In the present work, two photosensitizing drugs, Temoporfin and Verteporfin have been studied. Both have regular approval in Europe, Temoporfin for the treatment of head and neck cancers and Verteporfin for the treatment of age-related macular degeneration (AMD). The treatment modality, known as "Photodynamic Therapy" (PDT), involves drug activation with visible light in the presence of oxygen and production of reactive oxygen species (ROS) to destroy the pathological tissues. Both drugs are inactive in the absence of light, presenting only few side effects. The incorporation of the two drugs into a SOPC bilayer -used as a model membrane- was studied by ATR-FTIR. An original approach was applied, involving lyotropic transitions and a very slow dehydration rate of the sample. In low water content and dry film, Temoporfin highly affects stretching vibrations of SOPC chains and polar groups, showing that Temoporfin is inserted into the bilayer in both apolar and polar regions. In fully hydrated layers, Temoporfin - SOPC interactions still take place but only impact Temoporfin vibration bands. Verteporfin shows smaller effect on both chain and polar groups' vibrations of SOPC, with the exception of choline group, suggesting that Verteporfin is inserted into the bilayer to a lesser extent and remains at the bilayer polar interface. These results can be used to better understand drugs behavior in biological media.

Early Life Factors Influencing Children Gut Microbiota at 3.5 Years from Two French Birth Cohorts.

Early life gut microbiota-influencing factors may play an important role in programming individuals long-term health and substantial efforts have been devoted into studying the development of the gut microbiota in relation to early life events. This study aimed to examine in a single study, the persistence of associations between 20 factors occurring in the early life and the gut microbiota at 3.5 years of 798 children from two French nationwide birth cohorts, EPIPAGE 2 (very preterm children) and ELFE (late preterm and full-term children). Gut microbiota profiling was assessed using 16S rRNA gene sequencing-based method. Upon thorough adjustment of confounding factors, we demonstrated that gestational age was one of the factors most associated with gut microbiota differences with a noticeable imprint of prematurity at 3.5 years of age. Children born by cesarean section harbored lower richness and diversity and a different overall gut microbiota composition independently of preterm status. Children who had ever received human milk were associated with a Prevotella-driven enterotype (P_type) compared to those who had never received human milk. Living with a sibling was associated with higher diversity. Children with siblings and those attending daycare centers were associated with a P_type enterotype. Maternal factors including the country of birth and preconception maternal body mass index were associated with some microbiota characteristics: children born to overweight or obese mothers showed increased gut microbiota richness. This study reveals that multiple exposures operating from early life imprint the gut microbiota at 3.5 years that is a pivotal age when the gut microbiota acquires many of its adult characteristics.

Statistical methodology for the detection of small changes in distances by EXAFS: application to the antimalarial ruthenoquine.

Antimalarial compounds ruthenoquine and methylruthenoquine were studied by X-ray absorption spectroscopy both in solid state and in solution, in normal (aqueous or CH(2)Cl(2) solutions) and oxidative (aqueous solution with H(2)O(2), either equimolar or in large excess) conditions, to detect small changes in the coordination sphere of the ruthenium atom. Since changes in the EXAFS spectra of these compounds are quite subtle, a complete procedure was developed to assess the different sources of uncertainties in fitted structural parameters, including the use of multivariate statistic methods for simultaneous comparison of edge energy correction ΔE(0) and distances, which can take into account the very strong correlation between these two parameters. Factors limiting the precision of distance determination depend on the recording mode. In transmission mode, the main source of uncertainty is the data reduction process, whereas in fluorescence mode, experimental noise is the main source of variability in the fitted parameters. However, it was shown that the effects of data reduction are systematic and almost identical for all compounds; hence, they can be ignored when comparing distances. Consequently, for both fluorescence and transmission recorded spectra, experimental noise is the limiting factor for distance comparisons, which leads to the use of statistical methods for comparing distances. Univariate methods, focusing on the distance only, are shown to be less powerful in detecting changes in distances than bivariate methods making a simultaneous comparison of ΔE(0) and distances. This bivariate comparison can be done either by using the Hotelling's T(2) test or by using a graphical comparison of Monte Carlo simulation results. We have shown that using these methods allows for the detection of very subtle changes in distances. When applied to ruthenoquine compounds, it suggests that the implication of the nonbinding doublet of the aminoquine nitrogen in either protonation or methylation enhances the tilt of the two cyclopentadienyls. It also suggests that ruthenoquine and methylruthenoquine are, at least partially, oxidized in the presence of H(2)O(2), with a small decrease in the Ru-C bond length and increase in the edge energy.

Decreased steroidogenic enzyme activity in benign adrenocortical tumors is more pronounced in bilateral lesions as determined by steroid profiling in LC-MS/MS during ACTH stimulation test.

Objective: Large response of steroid precursors, including 17-hydroxyprogesterone, to adrenocorticotropic hormone (ACTH) has been described in adrenocortical tumors, suggesting the existence of intra-tumoral enzymatic deficiencies. This study aimed to compare steroidogenesis enzymes activity in unilateral and bilateral benign tumors using serum steroid profiling in liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) in the basal state and after ACTH 1-24 stimulation. Design and methods: A serum profile of seven consecutive adrenal steroids was determined in LC-MS/MS in the basal state (T0) and after ACTH 1-24 stimulation (T60) in 35 patients with bilateral adrenocortical tumors (BL), 38 patients with unilateral tumors (UL) and 37 control subjects (CT). Response amplitude of each individual steroid was evaluated by T60/T0 ratio, whereas enzymatic activity was assessed by the downstream/upstream steroid ratio. Adrenal volume was quantified by a semi-automatic segmentation method. Results: For the seven steroids assayed, the amplitude of response to ACTH was higher in BL than in UL and in CT. The difference between BL and UL persisted even after matching patients on adrenal volume. On glucocorticoids pathway, enzymatic activity of CYP11B1 was significantly decreased in BL (78.3 (43.1-199.4)) in comparison to both UL (122.7 (13.8-228.4), P = 0.0002) and CT (186.8 (42.1-1236.3), P < 0.0001). On mineralocorticoids and androgens pathways, the enzymatic activity of CYP11B2 and CYP17A1-17,20 lyase was also lower in BL than UL and CT. Conclusions: Decreased activity of distal steroidogenesis enzymes CYP11B1, CYP11B2 and CYP17A1-17,20 lyase, responsible for an explosive response to ACTH of upstream precursors in bilateral tumors, limits the synthesis of bioactive steroids, in particular cortisol, despite the increase in adrenal mass. Significance statement: Activity of distal steroidogenesis enzymes (CYP11B1, CYP11B2 and CYP17A1 on glucocorticoids, mineralocorticoids and androgens pathways, respectively) is decreased in adrenocortical benign tumors. This decrease is more pronounced in bilateral lesions and seems to depend more on the nature of the lesion than on the increase in adrenal volume. It is responsible for the explosive response to ACTH of steroid precursors located upstream of these enzymes. It probably allows bioactive steroids, particularly cortisol, to stay in the normal range for a long time despite the increase in adrenal mass.

Opioid epidemic: Does rheumatological practice favors risk for patients? National survey on rheumatologists' opioid prescriptions and compliance to guidelines for strong opioid prescription.

OBJECTIVES: Given the scope of rheumatology and its prevalence of pain, it seems needed that a study should focus on prescription habits, in the midst of the international opioid epidemic and given the moderate efficacy of strong opioids in chronic musculoskeletal conditions. We compared rheumatologists' opioid prescribing patterns in non-cancer pain with recommended practice. METHODS: We performed a cross-sectional study of the French health insurance database, including all patients aged 16 years or over reimbursed for at least one strong opioid prescription from a rheumatologist in 2015. A nationwide survey of all registered rheumatologists in France was performed with a 47-item questionnaire in June 2015. RESULTS: Only 2.4% of the patients receiving a strong opioid in 2015 (n=700,946) had at least one prescription from a rheumatologist. Rheumatologists prescribed mostly morphine, and significantly less oxycodone and fentanyl (P<0.00001) than other specialists. Rheumatologists prescribed a mean of 35.8mg morphine equivalent/day. A response rate of 33.7% was obtained to the questionnaire. Acute musculoskeletal pain was the principal condition for strong opioids prescription, with 94.5% re-evaluating opioid treatment within two weeks of initiation. For efficacy, 80% said that they stopped treatment if no benefit was observed after a test period (mean=1.2 months). Rheumatologists with pain management training were significantly more likely to evaluate pain before prescribing strong opioids (P=0.001), evaluate efficacy within three months (P=0.01) and screen for risk factors for misuse at initiation (P<0.0001). CONCLUSIONS: For non-cancer pain, rheumatologists generally prescribe opioids for short periods, at low doses, mostly according to national recommendations. Pain education strongly affected opioid prescription by rheumatologists.

Functional and phylogenetic alterations in gut microbiome are linked to graft-versus-host disease severity.

Acute graft-versus-host disease (aGVHD) is the main complication of hematopoietic stem cell transplantation (HSCT). Changes in gut microbiota composition have been associated with subsequent aGVHD, and reconstitution of healthy microbiota is currently being explored as a therapeutic approach. However, the specific actors in the intestinal ecosystem involved in the pathologic process at the time of aGVHD onset are not yet fully known. We prospectively collected stool samples from patients who underwent allogeneic HSCT. Patients sampled at aGVHD onset were compared with non-GVHD patients. To identify phylogenetic and functional signatures of the disease process, we determined fecal short-chain fatty acid (SFCA) profiles and used high-throughput DNA sequencing and real-time quantitative polymerase chain reaction to assess the microbiota composition. Microbiota alterations were highly specific of gastrointestinal (GI) aGVHD severity. Bacterial biomass and α-diversity were lower in severe aGVHD. We identified several bacterial signatures associated with severe aGVHD at disease onset; a negative correlation was observed with anaerobic bacteria of the Lachnospiraceae, especially the Blautia genus, and Ruminococcaceae families. In parallel, in severe aGVHD patients, we showed a dramatic decrease in the levels of the main SFCAs: acetate (75.8%), propionate (95.8%), and butyrate (94.6%). Mild aGVHD patients were characterized by conserved levels of propionate and Blautia propionate producers. Butyrate was significantly decreased in all GI aGVHD stages, representing a potential diagnostic marker of the disease. Specific microbiota and metabolic alterations were thus associated with aGVHD severity and may be useful for diagnostic and pathophysiologic purposes.

Freeze-dried fecal samples are biologically active after long-lasting storage and suited to fecal microbiota transplantation in a preclinical murine model of Clostridioides difficile infection.

Fecal microbiota transplantation is now recommended for treating recurrent forms of Clostridioides difficile infection. Recent studies have reported protocols using capsules of either frozen or freeze-dried stool allowing oral administration in in- and out-patient settings. However, a central question remains the viability, engraftment, and efficacy of the microbiome over time during storage life. This study shows that both the freeze-drying and freezing procedures for fecal samples allowed preserving viability, short-chain fatty acids concentration, and anti-Clostridioides difficile properties of microbiota without significant alteration after storage for 12 months. Fecal transplantation with freeze-dried microbiota allowed engraftment of microbiota leading to clearance of Clostridioides difficile infection in a preclinical murine model with a survival rate of 70% versus 53-60% in mice treated with frozen inocula, and 20% in the untreated group. Moreover, the freeze-dried powder can be used to fill oral hard capsules using a very low amount (0.5%) of glidant excipient, allowing oral formulation. Altogether, this study showed that freeze-dried inocula can be used for the treatment of Clostridioides difficile infection with long-lasting stability of the fecal microbiota. This formulation facilitates biobanking and allows the use of hard capsules, an essential step to simplify patient access to treatment.

Effect of an immune-enhancing diet on lymphocyte in head-injured rats: what is the role of arginine?

OBJECTIVE: The benefit of immune-enhancing diets (IEDs) in the intensive care unit remains controversial. Considering their complexity, the role of each component, in particular arginine (Arg), in their properties is largely unknown. The aim of this study was to determine the role of arginine in the immunomodulatory effects of an IED (Crucial) in head-injured rats. DESIGN: Thirty-four rats were randomized into five groups: AL (ad libitum), HI (head-injured), HI-STD (HI + standard enteral nutrition, EN), HI-STD-Arg (HI + standard EN + Arg in equimolar concentration to Arg in IED), and HI-IED (HI + IED). These isocaloric and isonitrogenous diets were administered over 4 days. After death, the thymus was removed and weighed. The density of CD25, CD4 and CD8 on lymphocytes from blood and from Peyer patches was evaluated. Mesenteric lymph nodes, liver and spleen were cultured for analysis of enterobacterial translocation and dissemination. MEASUREMENTS AND RESULTS: HI induced an atrophy of the thymus which was not corrected by the standard diet (HI 0.27 +/- 0.03, HI-STD 0.35 +/- 0.03 vs. AL 0.49 +/- 0.02 g; p < 0.05). However, the standard diet supplemented with arginine limited the thymic atrophy and the IED restored thymus weight. CD25 density and interleukin-2 production were increased only in the HI-STD-Arg and HI-IED groups (p < 0.05). Head injury induced enterobacterial translocation and dissemination which were blunted only in the HI-STD-Arg group (p < 0.05). CONCLUSIONS: In this rat HI model, arginine appears to be safe, contributes to a large extent to the immunomodulatory effects of the IED, and seems to limit enterobacterial translocation and dissemination more efficiently alone than in an IED.

Effect of oligofructose supplementation on gut microflora and well-being in young children attending a day care centre.

The effect of daily administration of oligofructose (OF) on 7-19 months old healthy children intestinal microflora, intestinal tolerance and well-being was assessed in a double blind placebo controlled study. The study comprised 8 days of observation, 21 days of supplementation, and 15 days of post-supplementation. Exclusion criteria included antibiotic use and intake of other prebiotic and probiotic at any time following enrolment. Faecal flora was analysed by culture methods, and health information was recorded daily. Bifidobacteria, tended to slightly increase with OF supplementation, but not with placebo (p=0.095). Simultaneously, a decrease in potential pathogens, significant for clostridia (p=0.05) but not for staphylococci (p=0.09) was observed in the OF group. These modifications did not persist during the post-supplementation period. OF supplementation were accompanied by less flatulence, diarrhoea, vomiting (p<0.001), and fever (p<0.05) events.

Ornithine Aminotransferase, an Important Glutamate-Metabolizing Enzyme at the Crossroads of Multiple Metabolic Pathways.

Ornithine δ-aminotransferase (OAT, E.C. 2.6.1.13) catalyzes the transfer of the δ-amino group from ornithine (Orn) to α-ketoglutarate (aKG), yielding glutamate-5-semialdehyde and glutamate (Glu), and vice versa. In mammals, OAT is a mitochondrial enzyme, mainly located in the liver, intestine, brain, and kidney. In general, OAT serves to form glutamate from ornithine, with the notable exception of the intestine, where citrulline (Cit) or arginine (Arg) are end products. Its main function is to control the production of signaling molecules and mediators, such as Glu itself, Cit, GABA, and aliphatic polyamines. It is also involved in proline (Pro) synthesis. Deficiency in OAT causes gyrate atrophy, a rare but serious inherited disease, a further measure of the importance of this enzyme.

Geriatric Nutritional Risk Index: a new index for evaluating at-risk elderly medical patients.

BACKGROUND: Patients at risk of malnutrition and related morbidity and mortality can be identified with the Nutritional Risk Index (NRI). However, this index remains limited for elderly patients because of difficulties in establishing their normal weight. OBJECTIVE: Therefore, we replaced the usual weight in this formula by ideal weight according to the Lorentz formula (WLo), creating a new index called the Geriatric Nutritional Risk Index (GNRI). DESIGN: First, a prospective study enrolled 181 hospitalized elderly patients. Nutritional status [albumin, prealbumin, and body mass index (BMI)] and GNRI were assessed. GNRI correlated with a severity score taking into account complications (bedsores or infections) and 6-mo mortality. Second, the GNRI was measured prospectively in 2474 patients admitted to a geriatric rehabilitation care unit over a 3-y period. RESULTS: The severity score correlated with albumin and GNRI but not with BMI or weight:WLo. Risk of mortality (odds ratio) and risk of complications were, respectively, 29 (95% CI: 5.2, 161.4) and 4.4 (95% CI: 1.3, 14.9) for major nutrition-related risk (GNRI: <82), 6.6 (95% CI: 1.3, 33.0), 4.9 (95% CI: 1.9, 12.5) for moderate nutrition-related risk (GNRI: 82 to <92), and 5.6 (95% CI: 1.2, 26.6) and 3.3 (95% CI: 1.4, 8.0) for a low nutrition-related risk (GNRI: 92 to < or =98). Accordingly, 12.2%, 31.4%, 29.4%, and 27.0% of the 2474 patients had major, moderate, low, and no nutrition-related risk, respectively. CONCLUSION: GNRI is a simple and accurate tool for predicting the risk of morbidity and mortality in hospitalized elderly patients and should be recorded systematically on admission.

Speciation of new tri- and tetra-glucoconjugated tetrapyrrolic macrocycles (porphyrins and chlorins): an electronic molecular spectroscopy study.

In this work, we study the physicochemical properties of some newly developed glycoconjugated photosensitizers that can be used in photodynamic therapy (PDT) of cancers: meso-tri- and tetra-(meta-O-beta-D-glucosyloxyphenyl)porphyrins and meso-, tri-, and tetra-(meta-O-beta-D-glucosyloxyphenyl)chlorins. Their properties are compared to the non-glycosylated hydroxylated parent compounds meso-tetra-(meta-hydroxyphenyl) porphyrin and meso-tetra-(meta-hydroxyphenyl)chlorin. It was found that at the ground state, all porphyrins present, independent of the substitution, have the same mean ionization constant (pKa = 2.7), corresponding to two indistiguishable steps of protonation of tetrapyrrolic nitrogens. On the other hand, in the case of chlorins, one proton process can be observed and the corresponding nitrogen exhibits a slightly superior basicity (pKa = 3.0) with respect to porphyrins. Hydroxylated compounds present a second transition at high pH corresponding to the ionization of phenol groups (pKa = 10.5). Consequently, all photosensitizers are not charged at physiological pH (approximately 7.4), and so the ionization process does not influence their activity in biological media. Ionization induces very important variations in photosensitizer absorption and emission spectra. For example, absorption in the red region (band V), one of the most important characteristics of a good photosensitizer, is only important for diprotonated porphyrins and neutral chlorins. As far as fluorescence emission is concerned, neutral chlorins are almost six times more fluorescent than the corresponding neutral porphyrins (phi(chlorin)/phi(porphyrin) approximately = 6). It should be emphasized that the spectra modifications induced by pH variations can find interesting applications in the optimization of visible and fluorescence detection in high-performance liquid chromatography (HPLC) as well as in the development of direct, rapid fluorimetric analytical methods.

New insights into handling missing values in environmental epidemiological studies.

Missing data are unavoidable in environmental epidemiologic surveys. The aim of this study was to compare methods for handling large amounts of missing values: omission of missing values, single and multiple imputations (through linear regression or partial least squares regression), and a fully Bayesian approach. These methods were applied to the PARIS birth cohort, where indoor domestic pollutant measurements were performed in a random sample of babies' dwellings. A simulation study was conducted to assess performances of different approaches with a high proportion of missing values (from 50% to 95%). Different simulation scenarios were carried out, controlling the true value of the association (odds ratio of 1.0, 1.2, and 1.4), and varying the health outcome prevalence. When a large amount of data is missing, omitting these missing data reduced statistical power and inflated standard errors, which affected the significance of the association. Single imputation underestimated the variability, and considerably increased risk of type I error. All approaches were conservative, except the Bayesian joint model. In the case of a common health outcome, the fully Bayesian approach is the most efficient approach (low root mean square error, reasonable type I error, and high statistical power). Nevertheless for a less prevalent event, the type I error is increased and the statistical power is reduced. The estimated posterior distribution of the OR is useful to refine the conclusion. Among the methods handling missing values, no approach is absolutely the best but when usual approaches (e.g. single imputation) are not sufficient, joint modelling approach of missing process and health association is more efficient when large amounts of data are missing.

Long-lasting improved amino acid bioavailability associated with protein pulse feeding in hospitalized elderly patients: a randomized controlled trial.

OBJECTIVE: Aging is associated with a blunted anabolic response to dietary intake, possibly related to a decrease in systemically available amino acids (AAs), which in turn may stem from increased splanchnic AA metabolism. Splanchnic sequestration can be saturated by pulse feeding (80% of daily protein intake in a single meal), enabling increased protein synthesis. The aim of this study was to explore whether protein pulse feeding increased postprandial AA concentrations, and if so whether this increase persisted after 6 wk of dietary treatment. METHODS: This prospective randomized study enrolled 66 elderly malnourished or at-risk patients in an inpatient rehabilitation unit. All were given a controlled diet for 6 wk. In a spread diet (SD) group (n = 36), dietary protein was spread over the four daily meals. In a pulse diet (PD) group (n = 30), 72% of dietary protein (averaging 1.31 g/kg body weight daily) was consumed in one meal at noon. The patients were evaluated on day 1 and at 6 wk for plasma postprandial (five times from 0 to +180 min) AA concentrations (expressed as area under the curve above baseline). RESULTS: Protein pulse feeding was more efficient than protein spread feeding at increasing plasma postprandial AA concentrations, notably of essential AAs. This increased postprandial AA bioavailability was maintained after 6 wk. CONCLUSIONS: This study demonstrates that increased postprandial AA bioavailability induced by protein pulse feeding persists after 6 wk (i.e., that there is no metabolic adaptation blunting AA bioavailability).

Impact of protein pulse feeding on lean mass in malnourished and at-risk hospitalized elderly patients: a randomized controlled trial.

BACKGROUND & AIMS: Aging is associated with a blunted anabolic response to dietary intake, possibly related to a decrease in systemically available amino acids (AAs), which in turn may stem from increased splanchnic AA metabolism. This splanchnic sequestration can be saturated by pulse feeding (80% of daily protein intake in a single meal), enabling increased protein synthesis. This study aimed to evaluate the efficacy of a new nutritional strategy, termed protein pulse feeding. METHODS: This prospective randomized study (ClinicalTrials.gov registration number NCT00135590) enrolled 66 elderly malnourished or at-risk patients in an inpatient rehabilitation unit. All were given a controlled diet for 6 weeks. In a spread diet (SD) group (n = 36), dietary protein was spread over the four daily meals. In a pulse diet (PD) group (n = 30), 72% of dietary protein (1.31 g/kg weight/d on average) was consumed in one meal at noon. The patients were evaluated at admission and at 6 weeks for body composition [lean mass (LM), appendicular skeletal muscle mass (ASMM), and body cell mass (BCM) indices, measured by X-ray absorptiometry combined with bioelectrical impedance analysis] (primary outcome), hand grip strength, and activities of daily living (ADL) score. RESULTS: Protein pulse feeding was significantly more efficacious than protein spread feeding in improving LM index (mean changes from baseline for PD group: +0.38 kg/m(2); 95% confidence interval (CI), [0; 0.60]; for SD group: -0.21 kg/m(2); 95% CI, [-0.61; 0.20]; p = 0.005 between the two groups), ASMM index (+0.21 kg/m(2); 95% CI, [0; 0.34] and -0.11 kg/m(2); 95% CI, [-0.20; 0.09]; p = 0.022), BCM index (+0.44 kg/m(2); 95% CI, [0.08; 0.52] and -0.04 kg/m(2); 95% CI, [-0.09; 0.10]; p = 0.004). There was no significant effect for hand-grip strength or ADL score. CONCLUSIONS: This study demonstrates for the first time that protein pulse feeding has a positive, clinically relevant effect on lean mass in malnourished and at-risk hospitalized elderly patients.

Infant gut microbiota is protective against cow's milk allergy in mice despite immature ileal T-cell response.

Faecal microbiota of healthy infant displays a large abundance of Bifidobacterium spp. and Bacteroides spp. Although some studies have reported an association between these two genera and allergy, these findings remain a subject of debate. Using a gnotobiotic mouse model of cow's milk allergy, we investigated the impact of an infant gut microbiota ­ mainly composed of Bifidobacterium and Bacteroides spp. ­ on immune activation and allergic manifestations. The transplanted microbiota failed to restore an ileal T-cell response similar to the one observed in conventional mice. This may be due to the low bacterial translocation into Peyer's patches in gnotobiotic mice. The allergic response was then monitored in germ-free, gnotobiotic, and conventional mice after repeated oral sensitization with whey proteins and cholera toxin. Colonized mice displayed a lower drop of rectal temperature upon oral challenge with b-lactoglobulin, lower plasma mMCP-1, and lower anti-BLG IgG1 than germ-free mice. The foxp3 gene was highly expressed in the ileum of both colonized mice that were protected against allergy. This study is the first demonstration that a transplanted healthy infant microbiota mainly composed of Bifidobacterium and Bacteroides had a protective impact on sensitization and food allergy in mice despite altered T-cell response in the ileum.