Effect of Infant Formula Containing a Low Dose of the Probiotic Bifidobacterium lactis CNCM I-3446 on Immune and Gut Functions in C-Section Delivered Babies: A Pilot Study.

BACKGROUND: In the absence of breast-feeding and its immunomodulatory factors, supplementation of starter infant formula (IF) with probiotics is currently used to support immune functions and gut development. AIM: To assess whether immune-related beneficial effects of regular dose (10(7) CFU/g of powder) of the probiotic Bifidobacterium lactis CNCM I-3446 (hereafter named B. lactis) in starter IF supplementation can be maintained with starter IF containing a low dose (10(4) CFU/g of powder) of B. lactis. METHOD: This trial was designed as a pilot, prospective, double-blind, randomized, single-center clinical trial of two parallel groups (n = 77 infants/group) of C-section delivered infants receiving a starter IF containing either low dose or regular dose of the probiotic B. lactis from birth to six months of age. In addition, a reference group of infants breast-fed for a minimum of four months (n = 44 infants), also born by C-section, were included. All groups were then provided follow-up formula without B. lactis up to 12 months of age. Occurrence of diarrhea, immune and gut maturation, responses to vaccinations, and growth were assessed from birth to 12 months. The effect of low-dose B. lactis formula was compared to regular-dose B. lactis formula, considered as reference for IF with probiotics, and both were further compared to breast-feeding as a physiological reference. RESULTS: Data showed that feeding low-dose B. lactis IF provides similar effects as feeding regular-dose B. lactis IF or breast milk. No consistent statistical differences regarding early life protection against gastrointestinal infections, immune and gut maturation, microbiota establishment, and growth were observed between randomized formula-fed groups as well as with the breast-fed reference group. CONCLUSION: This pilot study suggests that supplementing C-section born neonates with low-dose B. lactis-containing starter formula may impact immune as well as gut maturation similarly to regular-dose B. lactis, close to the breast-feeding reference.

Ordered arrays of Au catalysts by FIB assisted heterogeneous dewetting.

Synthesizing Au0.8Si0.2 nanocatalysts that are homogeneous in size and have controlled position is becoming a challenging and crucial prequisite for the fabrication of ordered semiconductor nanowires. In this study, Au0.8Si0.2 nanocatalysts are synthesized via dewetting of Au layers on Si(111) during thermal annealing in an ultra-high vacuum. In the first part of the paper, the mechanism of homogeneous dewetting is analyzed as a function of the Au-deposited thickness (h Au). We distinguish three different dewetting regimes: (I) for a low thickness ([Formula: see text]), a submonolyer coverage of Au is stabilized and there is no dewetting. (II) For an intermediate thickness ([Formula: see text]), there is both dewetting and Au0.8Si0.2 phase formation. The size and density of the Au0.8Si0.2 clusters are directly related to h Au. When cooling down to room temperature, the clusters decompose and reject the Si at the Au/Si substrate interface. (III) For a large thickness ([Formula: see text]), only dewetting takes place, without forming AuSi clusters. In this regime, the dewetting is kinetically controlled by the self-diffusion of Au (activation energy ∼0.43 eV) without evidence of an Si-alloying effect. As a practical consequence, when relying solely on the homogeneous dewetting of Au/Si(111) to form the Au0.8Si0.2 catalysts (without a supply of Si atoms from vapor), regime II should be used to obtain good size and density control. In the second part of the paper, a process for ordering the catalysts using focused ion beam-(FIB) assisted dewetting (heterogeneous dewetting) is developed. We show that no matter what the FIB milling conditions and the Au nominal thickness are, dewetting is promoted by ion beam irradiation and is accompanied by the formation of Au0.8Si0.2 droplets. The droplets preferentially form on the patterned areas, while in similar annealing conditions, they do not form on the unpatterned areas. This behavior is attributed to the larger Au-Si interdiffusion in the patterned areas, which results from the Si amorphization induced by the FIB. A systematic analysis of the position of the nanodroplets shows their preferential nucleation inside the patterns, while thicker platelets of almost pure Au are observed between the patterns. The evolutions of the size homogeneity and the occupancy rate of the patterns are quantified as a function of the FIB dose and annealing temperature. Nice arrays of perfectly ordered AuSi catalysts are obtained after optimizing the FIB and dewetting conditions.

[DXA imaging: the multifunction Swiss army knife?]. / Imagerie par DXA: le couteau suisse multifonction?

The significant progress on the quality and resolution of the images obtained by "Dual X-ray Absorptiometry" or DXA has permitted on one hand to improve some existing features and on the other to develop new ones, significantly refining the care of our patients in various pathologies. For example, by improving the prediction of fracture risk by indirect analysis of micro- and macro-architecture of the bone, by looking for markers of associated bone diseases (research vertebral fractures or atypical femoral fractures), or by assessing the metabolic status by the measurement of body composition. With the best performing DXA devices we will soon be able, in clinical routine, to determine bone age, to estimate cardiovascular risk (by measuring the calcification of the abdominal aorta) or to predict the progression of joint osteoarthritis and its evolution after surgical management.

Selective growth and ordering of SiGe nanowires for band gap engineering.

Selective growth and self-organization of silicon-germanium (SiGe) nanowires (NWs) on focused ion beam (FIB) patterned Si(111) substrates is reported. In its first step, the process involves the selective synthesis of Au catalysts in SiO2-free areas; its second step involves the preferential nucleation and growth of SiGe NWs on the catalysts. The selective synthesis process is based on a simple, room-temperature reduction of gold salts (Au³âºCl4⁻) in aqueous solution, which provides well-organized Au catalysts. By optimizing the reduction process, we are able to generate a bidimensional regular array of Au catalysts with self-limited sizes positioned in SiO2-free windows opened in a SiO2/Si(111) substrate by FIB patterning. Such Au catalysts subsequently serve as preferential nucleation and growth sites of well-organized NWs. Furthermore, these NWs with tunable position and size exhibit the relevant features and bright luminescence that would find several applications in optoelectronic nanodevices.

Diffusion induced effects on geometry of Ge nanowires.

We report diffusion induced germanium nanowire growth and its dependence on the Ge evaporation flux. The wires show a growth rate (dL/dt) in agreement with the previously reported models, but detection of anomalies in the grown wires may indicate the prevalence of the direct Ge impinging effect on large diameter wires. Additionally, we demonstrate that change in deposition flux could directly affect the diffusion length of the Ge adatoms on the wire sidewalls. This in turn modifies the geometry of the grown wires by introducing a lateral growth starting from the base of the wire. A detailed understanding of the deposition flux effect on the growth and geometry of wires will result in improved knowledge of physical properties of wires.

[Long-term implication of bariatric surgery: beyond deficiencies]. / Implications à long terme de la chirurgie bariatrique: au-delà des carences.

Bariatric surgery frequently leads to several nutritional deficiencies that are well reported in the literature. However, numerous other aspects of the patients' life are concerned by bariatric interventions, so that the follow-up of these patients after bariatric surgery does not only encompass a mere correction of the well-known nutritional deficiencies. Only a thorough knowledge of all possible consequences of bariatric interventions permits an adequate follow-up of these patients. Overtly addressing all these issues with the patients before performing a bariatric intervention is the best way for them to be prepared for the intervention itself and to understand the need of a life-long follow-up thereafter.

Bright photoluminescence from ordered arrays of SiGe nanowires grown on Si(111).

We report on the optical properties of SiGe nanowires (NWs) grown by molecular beam epitaxy (MBE) in ordered arrays on SiO2/Si(111) substrates. The production method employs Au catalysts with self-limited sizes deposited in SiO2-free sites opened-up in the substrate by focused ion beam patterning for the preferential nucleation and growth of these well-organized NWs. The NWs thus produced have a diameter of 200 nm, a length of 200 nm, and a Ge concentration x = 0.15. Their photoluminescence (PL) spectra were measured at low temperatures (from 6 to 25 K) with excitation at 405 and 458 nm. There are four major features in the energy range of interest (980-1120 meV) at energies of 1040.7, 1082.8, 1092.5, and 1098.5 meV, which are assigned to the NW-transverse optic (TO) Si-Si mode, NW-transverse acoustic (TA), Si-substrate-TO and NW-no-phonon (NP) lines, respectively. From these results the NW TA and TO phonon energies are found to be 15.7 and 57.8 meV, respectively, which agree very well with the values expected for bulk Si1- x Ge x with x = 0.15, while the measured NW NP energy of 1099 meV would indicate a bulk-like Ge concentration of x = 0.14. Both of these concentrations values, as determined from PL, are in agreement with the target value. The NWs are too large in diameter for a quantum confinement induced energy shift in the band gap. Nevertheless, NW PL is readily observed, indicating that efficient carrier recombination is occurring within the NWs.

Ferromagnetic Mn-doped Si0.3Ge0.7 nanodots self-assembled on Si(100).

Densely packed epitaxial Mn-doped Si(0.3)Ge(0.7) nanodots self-assembled on Si(100) have been obtained. Their structural properties were studied using reflection high-energy electron diffraction, energy dispersive x-ray diffraction, atomic force microscopy, extended x-ray absorption fine structure measurements and high-resolution transmission electron microscopy. Mn(5)Ge(1)Si(2) crystallites embedded in Si(0.3)Ge(0.7) were found. They exhibit a ferromagnetic behaviour with a Curie temperature of about 225 K.

Low dose endoluminal photodynamic therapy improves murine T cell-mediated colitis.

BACKGROUND AND STUDY AIMS: Low dose photodynamic therapy (LDPDT) may modify the mucosal immune response and may thus provide a therapy for Crohn's disease. We evaluated the efficacy and safety of this technique in a murine T cell-mediated colitis model. METHODS: The safety of LDPDT was first tested in BALB/c mice. Naïve T cells were used to induce colitis in mice with severe combined immunodeficiency, which were followed up endoscopically, and a murine endoscopic index of colitis (MEIC) was developed. The efficacy of LDPDT (10 J/cm (2); delta-aminolevulinic acid, 15 mg/kg bodyweight) was then tested on mice with moderate colitis, while a disease control group received no treatment. The MEIC, weight, length, and histology of the colon, cytokine expression indices, number of mucosal CD4 (+) T cells, percentage of apoptotic CD4 (+) T cells, body weight, and systemic side effects were evaluated. RESULTS: LDPDT improved the MEIC ( P = 0.011) and the histological score ( P = 0.025), diminished the expression indices of the proinflammatory cytokines, interleukin-6 ( P = 0.042), interleukin-17 ( P = 0.029), and interferon-gamma ( P = 0.014), decreased the number of mucosal CD4 (+) T cells, and increased the percentage of apoptotic CD4 (+) T cells compared with the disease control group. No local or systemic side effects occurred. CONCLUSION: LDPDT improves murine T cell-mediated colitis, decreases the proinflammatory cytokines interleukin-6, interleukin-17, and interferon-gamma, and decreases the number of CD4 (+) T cells. No adverse events were observed. Therefore, this technique is now being evaluated in patients with inflammatory bowel disease.

[Management of hyperinsulinemic hypoglycemia post-gastric bypass surgery]. / Gestion des hypoglycémies après le bypass gastrique.

Gastric bypass surgery is an effective treatment for morbid obesity, allowing a substantial weight loss together with an improvement of the cardiovascular and metabolic comorbidities, particularly the glucose control. However, after gastric bypassing, an imbalance between sensitivity and insulin secretion may be observed. This disorder gives rise to hyperinsulinemic hypoglycemia (late dumping syndrome) and is characterized by a dizziness that can be disabling. This problem must be distinguished from conditions provoking similar symptoms, as for instance the early dumping syndrome and the food restriction-related hypoglycemia. Since all these conditions need a particular management, their distinction is essential.

[Progress in bronchoscopy: ultrasound guided fine-needle aspiration (EBUS-TBNA)]. / Progrès en bronchoscopie: ponction guidée par ultrasonographie (EBUS-TBNA).

In case of lung cancer, evaluation of the extension disease is mandatory. Mediastinal nodes must also be evaluated: if a controlateral to the tumor node is metastatic (N3), surgery is no more indicated. As specificity of PET-CT scan is not satisfaying (78%), cytology or histology of a suspect node is necessary. Even if PT-CT scan is negative, node micrometastasis are not excluded. To investigate a mediastinal adenopathy, mediastinoscopy or mediastinotomy are gold standard. Cytoponction guided by ultrasonography (EBUS-TBNA) is a new method which has been proved to be efficient and safe, but necessating some expertise and regular practice. It could be a valuable alternative to mediastinoscopy.

[Pneumonology. Ultrasound-guided transbronchial needle aspiration]. / Pneumologie. Cytoponction transbronchique guidée par uttrasonographie (EBUS-tBNA).

After discovering a lung cancer without extrathoracic metastases, the preoperative mediastinal check-up is of great importance to determine the patients operability. The 78% specificity of activity measuring FDG in a PET examination is clearly insufficient to avoid a biopsy of the incriminated lymph nodes. The investigation of a suspected malignant adenopathy justifies a complete examination by mediastinoscopy or-tomy, which are considered gold standards. The transbronchial fine needle aspiration guided by ultrasound (EBUS-TBNA) constitutes the recent evolution of TBNA, method known for 20 years now but underused. Depending on the operators skill, this new procedure needs a learning curve before being able to replace mediastinoscopy.

Role of Fas ligand expression in promoting escape from immune rejection in a spontaneous tumor model.

Tumors escape immune-mediated rejection by a variety of mechanisms during tumor progression. The elucidation of these mechanisms in vivo suffers from a lack of suitable models of spontaneous tumor formation escaping active specific immunotherapy (ASI). In a rat neu transgenic (rNeu-TG) mouse model of spontaneous breast tumor formation, we showed that rNeu-TG mice developed late escape tumors despite the presence of a persistent rNeu-specific immune response after ASI. Cell suspensions derived from these escape tumors grew in vaccinated tumor-free mice, whereas injected spontaneous tumor cells were rejected. Escape tumors retained rNeu or MHC class I expression but significantly upregulated Fas (CD95, Apo-1) ligand. We further demonstrated that Fas-L on escape tumor cells correlated with apoptosis of infiltrating T lymphocytes. Thus, our results provide evidence that spontaneous breast tumors upregulate Fas-L expression after vaccination that may promote tumor escape in vivo after ASI.

Comparative proteomics to establish genetic relationships in the Brassicaceae family.

The comparisons of the same proteome (aerial part of etiolated seedlings) in different species and genus of the plant family Brassicaceae (cabbages, mustards, rapes, radishes and Arabidopsis) was undertaken to establish genetic proximities between them. Genetic distances were calculated on the basis of common and distinct spots. The construction of phenetic trees and factorial correspondence analysis that were performed are in very good agreement with our actual knowledge of the taxonomy of the Brassicaceae. The position of the tetraploids, for instance, is in between the positions of their constitutive genome donor representatives. Comparative proteomics may be helpful to shorten the transfer between model and agronomic target species.

Targeting HER-2/neu for active-specific immunotherapy in a mouse model of spontaneous breast cancer.

The identification of tumor-associated antigens has led to increased interest in vaccination strategies to treat and/or prevent cancer. This study examined the feasibility of active-specific immunotherapy against the breast-tumor antigen HER-2/neu using a HER-2/neu transgenic (rNeu-TG) mouse model. rNeu-TG mice develop spontaneous breast tumors after pregnancy, indicating that they fail to mount an effective immune response against rNeu. Allogeneic fibroblasts expressing HER-2/neu were used as a cell-based vaccine. Vaccination induced a rNeu-specific anti-tumor immune response that prevented tumor formation of transplanted breast-tumor cells, and also protected mice from spontaneous tumor formation. Both T-cell-mediated and humoral immune responses were detectable in vaccinated mice. Vaccination also protected tumor-bearing mice from a challenge with cell suspensions isolated from spontaneous tumors, indicating that rNeu-TG mice are not tolerant to rNeu, even after spontaneous tumor formation. However, established spontaneous tumors themselves were never affected. This observation correlated with T-cell infiltrations in the injected but not in the established spontaneous tumor. Thus, allogeneic fibroblasts are efficient vaccine vectors to prime a specific immune response against an over-expressed tumor antigen. Moreover, our results suggest striking differences in the immunological requirements for the rejection of an established vs. a transplanted tumor.

Female-biased dispersal in the monogamous mammal Crocidura russula: evidence from field data and microsatellite patterns.

We investigated dispersal patterns in the monogamous Crocidura russula, based both on direct field observations (mark-recapture data) and on genetic analyses (microsatellite loci). Natal dispersal was found to be low. Most juveniles settled within their natal territory or one immediately adjacent. Migration rate was estimated to two individuals per year and per population. The correlation between genetic and geographical distances over a 16 km transect implies that migration occurs over short ranges. Natal dispersal was restricted to first-litter juveniles weaned in early May; this result suggests a direct dependence of dispersal on reproductive opportunities. Natal dispersal was highly female biased, a pattern unusual among mammals. Its association with monogamy provides support for the resource-competition model of dispersal. Our results demonstrate that a state-biased dispersal can be directly inferred from microsatellite genotype distributions, which opens new perspectives for empirical studies in this area.

Origin and evolution of homologous repeated sequences in the mitochondrial DNA control region of shrews.

The complete mitochondrial DNA (mtDNA) control region was amplified and directly sequenced in two species of shrew, Crocidura russula and Sorex araneus (Insectivora, Mammalia). The general organization is similar to that found in other mammals: a central conserved region surrounded by two more variable domains. However, we have found in shrews the simultaneous presence of arrays of tandem repeats in potential locations where repeats tend to occur separately in other mammalian species. These locations correspond to regions which are associated with a possible interruption of the replication processes, either at the end of the three-stranded D-loop structure or toward the end of the heavy-strand replication. In the left domain the repeated sequences (R1 repeats) are 78 bp long, whereas in the right domain the repeats are 12 bp long in C. russula and 14 bp long in S. araneus (R2 repeats). Variation in the copy number of these repeated sequences results in mtDNA control region length differences. Southern blot analysis indicates that level of heteroplasmy (more than one mtDNA form within an individual) differs between species. A comparative study of the R2 repeats in 12 additional species representing three shrew subfamilies provides useful indications for the understanding of the origin and the evolution of these homologous tandemly repeated sequences. An asymmetry in the distribution of variants within the arrays, as well as the constant occurrence of shorter repeated sequences flanking only one side of the R2 arrays, could be related to asymmetry in the replication of each strand of the mtDNA molecule. The pattern of sequence and length variation within and between species, together with the capability of the arrays to form stable secondary structures, suggests that the dominant mechanism involved in the evolution of these arrays in unidirectional replication slippage.

Intra- and interindividual variation in flank gland secretions of free-ranging shrewsCrocidura russula.

Individual differences in flank gland secretions were examined among males of the monogamous shrewCrocidura russula during the breeding and nonbreeding seasons. Gas chromatography was used to measure intra- and interindividual variation of flank gland secretions of free-ranging shrews from different populations. The number of compounds detected by gas Chromatographic analyses was correlated with body mass, flank gland size, and the presence of blood parasites in individual shrews. Very few compounds were detected from the flank gland area of juvenile males. After they reached sexual maturity, however, the number of compounds detected from the flank gland secretions increased significantly. At the beginning of the reproductive season 48 different compounds were detected from male flank gland secretions. In the middle of the breeding season 70 compounds were detected, while only 11 compounds were detected during the nonbreeding season. Few compounds were common to all males. There were more volatile compounds in the flank gland secretions of males in the beginning of the breeding season than later in the breeding season. Males from the same population had fewer differences in the elution profile of compounds than males from different populations indicating that individuals from a distinct population have similar elution profiles of compounds and that each population has its own type of elution profile. No correlations were found between the number of compounds detected by gas chromatography for each male and the male's body mass or flank gland size. Blood parasites (trypanosomes,Trypanosoma crocidurae) were found in only three of 30 males investigated.