Post-immunobiotics increase resistance to primary respiratory syncytial virus infection and secondary pneumococcal pneumonia.

Previously, we demonstrated that post-immunobiotics derived from Lactobacillus gasseri TMT36, TMT39, and TMT40 strains (HK36, HK39 and HK40, respectively) differentially regulated Toll-like receptor 3 (TLR3)-mediated antiviral respiratory immunity in infant mice. In this work, we investigated whether the HK36, HK39 and HK40 nasal treatments were able to improve the resistance against primary respiratory syncytial virus (RSV) infection and secondary pneumococcal pneumonia. Our results demonstrated that the three treatments increased the resistance to primary viral infection by reducing variations in body weight, RSV titers and lung damage of infected infant mice. Post-immunobiotics significantly enhanced the expressions of interferon (IFN)-λ, IFN-ß, IFN-γ, interleukin(IL) - 1ß, IL-6, IL-27, Mx1, RNAseL and 2'-5'-oligoadenylate synthetase 1 (OAS1) genes and decreased tumour necrosis factor (TNF)-α in alveolar macrophages of RSV-challenged mice. In addition, the studies in the model of RSV-Streptococcus pneumoniae superinfection showed that the HK39 and HK40 treatments were capable of reducing lung damage, lung bacterial cell counts, and the dissemination of S. pneumoniae into the blood of infant mice. The protective effect was associated with increases in IFN-ß, IFN-γ, IL-10, and IL-27 in the respiratory tract. This study demonstrates that the nasal application of the post-immunobiotics HK39 and HK40 stimulates innate respiratory immunity and enhances the defences against primary RSV infection and secondary pneumococcal pneumonia offering an alternative to combat respiratory superinfections in children, which can be fatal.

Multipole polaron in the devil's staircase of CeSb.

Rare-earth intermetallic compounds exhibit rich phenomena induced by the interplay between localized f orbitals and conduction electrons. However, since the energy scale of the crystal-electric-field splitting is only a few millielectronvolts, the nature of the mobile electrons accompanied by collective crystal-electric-field excitations has not been unveiled. Here, we examine the low-energy electronic structures of CeSb through the anomalous magnetostructural transitions below the Néel temperature, ~17 K, termed the 'devil's staircase', using laser angle-resolved photoemission, Raman and neutron scattering spectroscopies. We report another type of electron-boson coupling between mobile electrons and quadrupole crystal-electric-field excitations of the 4f orbitals, which renormalizes the Sb 5p band prominently, yielding a kink at a very low energy (~7 meV). This coupling strength is strong and exhibits anomalous step-like enhancement during the devil's staircase transition, unveiling a new type of quasiparticle, named the 'multipole polaron', comprising a mobile electron dressed with a cloud of the quadrupole crystal-electric-field polarization.

Soymilk-fermented with Lactobacillus delbrueckii subsp. delbrueckii TUA4408L improves immune-health in pigs.

Lactobacillus delbrueckii subsp. delbrueckii TUA4408L has the ability to grow and ferment soymilk and is able to modulate the innate immune response of intestinal epithelial cells in vitro. These two properties prompt us to evaluate whether the soymilk fermented with the TUA4408L strain can induce beneficial immunomodulatory effects in vivo. For this purpose, pigs were selected as a preclinical model. The studies performed here demonstrated that the L. delbrueckii subsp. delbrueckii TUA4408L-fermented soymilk (TUA4408L FSM) reduced blood markers of inflammation and differentially regulated the expression of inflammatory and regulatory cytokines in the intestinal mucosa. These immunological changes induced by the TUA4408L FSM were associated to an enhanced resistance to pathogenic Escherichia coli and an improved grow performance and meat quality of pigs. The experiments and analysis in our study indicate that the immunobiotic TUA4408L FSM could be an interesting non-dairy functional food to beneficially modulate the intestinal immune system, improve protection against pathogens and reduce inflammatory damage. The preclinical study carried out here in pigs could have a better correlation in humans, compared to a rodent model. However, the clinical relevance of these findings still needs to be confirmed by further research, for example, in controlled human challenge studies.

New immunobiotics from highly proteolytic Lactobacillus delbrueckii strains: their impact on intestinal antiviral innate immune response.

Proteolytic starter cultures with intrinsic immunomodulatory activities are desirably features for the development of functional foods, which would significantly reduce the cost of their production (one-strain starter) having an additional beneficial effect on the host. In this work, Lactobacillus delbrueckii strains were selected according to their ability to efficiently hydrolyse ß-casein and to modulate the immune system. Among 36 strains evaluated, the highest proteolytic activities were found for L. delbrueckii subsp. lactis CRL581 and L. delbrueckii subsp. bulgaricus CRL656. The immunomodulatory effect of both strains and their ß-casein hydrolysates (CRL581 and CRL656 hydrolysates, respectively) were studied in a murine model. Balb/c mice were fed lactobacilli or their hydrolysates for three days. One day after the last lactobacilli or hydrolysate treatments, mice were challenged with the Toll-like receptor 3 (TLR3) agonist poly(I:C) by intraperitoneal injection. Before and after poly(I:C) challenge the phagocytic and microbicidal activity of peritoneal macrophages, intestinal immunoglobulin A (IgA), cytokine profile, and histological analysis of the intestine were analysed. L. delbrueckii subsp. lactis CRL581 significantly increased the activation of peritoneal macrophages as well as the levels of intestinal IgA, interleukin (IL)-10 and interferon (IFN)-γ when compared to untreated controls. In addition, the CRL581 strain was able to significantly reduce the intestinal inflammatory damage triggered by TLR3 activation. L. delbrueckii CRL581 increased the levels of IL-10, IFN-γ and IFN-ß, and reduced tumour necrosis factor alpha and IL-6 concentrations in the intestine of poly(I:C)-challenged mice. No immunomodulatory effects were observed for the CRL656 strain or for the CRL581 or CRL656 hydrolysates. The results of this work show that the technologically relevant and high proteolytic strain L. delbrueckii CRL581 is able to beneficially modulate the intestinal innate antiviral immune response. Although further studies with the CRL581 strain are required to corroborate and deepen its immunological effects, this bacterium is an interesting alternative for the development of new functional foods with antiviral capabilities.

Devil's staircase transition of the electronic structures in CeSb.

Solids with competing interactions often undergo complex phase transitions with a variety of long-periodic modulations. Among such transition, devil's staircase is the most complex phenomenon, and for it, CeSb is the most famous material, where a number of the distinct phases with long-periodic magnetostructures sequentially appear below the Néel temperature. An evolution of the low-energy electronic structure going through the devil's staircase is of special interest, which has, however, been elusive so far despite 40 years of intense research. Here, we use bulk-sensitive angle-resolved photoemission spectroscopy and reveal the devil's staircase transition of the electronic structures. The magnetic reconstruction dramatically alters the band dispersions at each transition. Moreover, we find that the well-defined band picture largely collapses around the Fermi energy under the long-periodic modulation of the transitional phase, while it recovers at the transition into the lowest-temperature ground state. Our data provide the first direct evidence for a significant reorganization of the electronic structures and spectral functions occurring during the devil's staircase.

Modulation of Toll-like receptor-mediated innate immunity in bovine intestinal epithelial cells by lactic acid bacteria isolated from feedlot cattle.

The ability of lactobacilli isolated from feedlot cattle environment to differentially modulate the innate immune response triggered by Toll-like receptors (TLRs) activation in bovine intestinal epithelial (BIE) cells was evaluated. BIE cells were stimulated with Lactobacillus mucosae CRL2069, Lactobacillus acidophilus CRL2074, Lactobacillus fermentum CRL2085 or Lactobacillus rhamnosus CRL2084 and challenged with heat-stable pathogen associated molecular patterns (PAMPs) from enterotoxigenic Escherichia coli (ETEC) to induce the activation of TLR4 or with polyinosinic:polycytidylic acid (poly(I:C)) to activate TLR3. Type I interferons, cytokines, chemokines and negative regulators of TLR signalling were studied by RT-PCR. L. mucosae CRL2069 significantly reduced the expression of interleukin (IL)-8 and monocyte chemoattractant protein (MCP)-1 in BIE cells in the context of TLR3 activation. L. mucosae CRL2069 also reduced the expression of tumour necrosis factor-α, IL-ß, MCP-1, and IL-8 in heat-stable ETEC PAMPs-challenged BIE cells. In addition, reduced expressions of IL-6, MCP-1, and IL-8 were found in BIE cells stimulated with L. rhamnosus CRL2084, although its effect was significantly lower than that observed for the CRL2069 strain. The reduced levels of pro-inflammatory factors in BIE cells induced by the CRL2069 and CRL2085 strains was related to their ability of increasing the expression of TLR negative regulators. L. mucosae CRL2069 significantly improved the expression of A20-binding inhibitor of NFκ-B activation 3 (ABIN-3), interleukin-1 receptor-associated kinase M (IRAK-M) and mitogen-activated protein kinase 1 (MKP-1) while L. rhamnosus CRL2084 augmented ABIN-3 expression in BIE cells. The results of this work suggest that among the studied strains, L. mucosae CRL2069 was able to regulate TLR3-mediated innate immune response and showed a remarkable capacity to modulate TLR4-mediated inflammation in BIE cells. The CRL2069 strain induce the up-regulation of three TLR negative regulators that would influence nuclear factor kB and mitogen-activated protein kinases signalling pathways while reducing the expression of pro-inflammatory cytokines and chemokines. Therefore, L. mucosae CRL2069 is an interesting immunobiotic candidate for the protection of the bovine host against TLR-mediated intestinal inflammatory damage.

Effective countermeasures for Salmonella contamination in actual oilmeal-manufacturing plant in India.

AIMS: Salmonella contamination in the manufacturing process of an overseas oilmeal plant was investigated and countermeasures for Salmonella contamination were evaluated. METHODS AND RESULTS: Salmonella was detected from deposits and adhered materials inside the main processing equipment. Specifically high contamination was observed in the equipment associated with the meal cooler, with several Salmonella serovars being detected. A number of Salmonella serovars were also detected in the equipment of the fine powder recovery process. To prevent Salmonella contamination of oilmeal products, effective countermeasures that have been employed in Japan were implemented. By removing residues from the equipment and disinfecting the interior of the equipment, a significant decrease in the contamination rate of oilmeal products was achieved compared to before sanitation (P < 0·05). CONCLUSIONS: Effective countermeasures to control Salmonella contamination in the overseas manufacturing process of oilmeal were established. SIGNIFICANCE AND IMPACT OF THE STUDY: This is the first report focusing on Salmonella countermeasures in an actual oilmeal-manufacturing plant overseas.

Deciphering the influence of paraimmunobiotic bifidobacteria on the innate antiviral immune response of bovine intestinal epitheliocytes by transcriptomic analysis.

Previously, we reported that the non-viable immunomodulatory Bifidobacterium infantis MCC12 and Bifidobacterium breve MCC1274 strains (paraimmunobiotic bifidobacteria) were able to increase the protection against rotavirus infection in bovine intestinal epithelial (BIE) cells. In order to gain insight into the influence of paraimmunobiotic bifidobacteria on the innate antiviral immune response of BIE cells, their effect on the transcriptomic response triggered by Toll-like receptor 3 (TLR3) activation was investigated. By using microarray technology and qPCR analysis, we obtained a global overview of the immune genes involved in the innate antiviral immune response in BIE cells. Activation of TLR3 by poly(I:C) in BIE cells significantly increased the expression of interferon (IFN)-α and IFN-ß, several interferon-stimulated genes, cytokines, and chemokines. It was also observed that both paraimmunobiotic bifidobacteria differently modulated immune genes expression in poly(I:C)-challenged BIE cells. Most notable changes were found in genes involved in antiviral defence (IFN-ß, MX1, OAS1X, MDA5, TLR3, STAT2, STAT3), cytokines (interleukin (IL)-6), and chemokines (CCL2, CXCL2, CXCL6) that were significantly increased in bifidobacteria-treated BIE cells. B. infantis MCC12 and B. breve MCC1274 showed quantitative and qualitative differences in their capacities to modulate the innate antiviral immune response in BIE cells. B. breve MCC1274 was more efficient than the MCC12 strain to improve the production of type I IFNs and antiviral factors, an effect that could be related to its higher ability to protect against rotavirus replication in BIE cells. Interestingly, B. infantis MCC12 showed a remarkable anti-inflammatory effect. The MCC12 strain was more efficient to reduce the expression of inflammatory cytokines and chemokines (IL-16, IL-20, CX3CL1) when compared with B. breve MCC1274. These results provided valuable information for the deeper understanding of the antiviral immune response of intestinal epithelial cells as well as the host-paraimmunobiotic interaction in the bovine host.

Lactobacillus fermentum UCO-979C beneficially modulates the innate immune response triggered by Helicobacter pylori infection in vitro.

Helicobacter pylori infection is associated with important gastric pathologies. An aggressive proinflammatory immune response is generated in the gastric tissue infected with H. pylori, resulting in gastritis and a series of morphological changes that increase the susceptibility to cancer development. Probiotics could present an alternative solution to prevent or decrease H. pylori infection. Among them, the use of immunomodulatory lactic acid bacteria represents a promising option to reduce the severity of chronic inflammatory-mediated tissue damage and to improve protective immunity against H. pylori. We previously isolated Lactobacillus fermentum UCO-979C from human gastric tissue and demonstrated its capacity to reduce adhesion of H. pylori to human gastric epithelial cells (AGS cells). In this work, the ability of L. fermentum UCO-979C to modulate immune response in AGS cells and PMA phorbol 12-myristate 13-acetate (PMA)-differentiated THP-1 (human monocytic leukaemia) macrophages in response to H. pylori infection was evaluated. We demonstrated that the UCO-979C strain is able to differentially modulate the cytokine response of gastric epithelial cells and macrophages after H. pylori infection. Of note, L. fermentum UCO-979C was able to significantly reduce the production of inflammatory cytokines and chemokines in AGS and THP-1 cells as well as increase the levels of immunoregulatory cytokines, indicating a remarkable anti-inflammatory effect. These findings strongly support the probiotic potential of L. fermentum UCO-979C and provide evidence of its beneficial effects against the inflammatory damage induced by H. pylori infection. Although our findings should be proven in appropriate experiments in vivo, in both H. pylori infection animal models and human trials, the results of the present work provide a scientific rationale for the use of L. fermentum UCO-979C to prevent or reduce H. pylori-induced gastric inflammation in humans.

Experimental Determination of the Topological Phase Diagram in Cerium Monopnictides.

Experimental determinations of bulk band topology in the solid states have been so far restricted to only indirect investigation through the probing of surface states predicted by electronic structure calculations. We here present an alternative approach to determine the band topology by means of bulk-sensitive soft x-ray angle-resolved photoemission spectroscopy. We investigate the bulk electronic structures of the series materials, Ce monopnictides (CeP, CeAs, CeSb, and CeBi). By performing a paradigmatic study of the band structures as a function of their spin-orbit coupling, we draw the topological phase diagram and unambiguously reveal the topological phase transition from a trivial to a nontrivial regime in going from CeP to CeBi induced by the band inversion. The underlying mechanism of the phase transition is elucidated in terms of spin-orbit coupling in concert with their semimetallic band structures. Our comprehensive observations provide a new insight into the band topology hidden in the bulk states.

Development of immune and microbial environments is independently regulated in the mammary gland.

Breastfeeding is important for mammals, providing immunological and microbiological advantages to neonates, together with the nutritional supply from the mother. However, the mechanisms of this functional diversity in the mammary gland remain poorly characterized. Here, we show that, similar to the gastrointestinal tract, the mammary gland develops immune and microbial environments consisting of immunoglobulin A (IgA) and the microflora, respectively, both of which are important for protecting neonates and the mother from infectious diseases. The IgA production and microflora development are coordinated in the gastrointestinal tract but seem to be independently regulated in the mammary gland. In particular, the chemokine (C-C motif) ligand 28 and poly-Ig receptor, crucial molecules for the IgA production in milk, were expressed normally in germ-free lactating mice but were almost undetectable in postweaning mothers, regardless of the microflora presence. Our findings offer insights into potentially improving the quality of breastfeeding, using both immunological and microbiological approaches.

Development of an in vitro immunobiotic evaluation system against rotavirus infection in bovine intestinal epitheliocytes.

The bovine intestinal epithelial cell line (BIE cells) expresses the Toll-like receptor (TLR)3 and is able to mount an antiviral immune response after the stimulation with poly(I:C). In the present study, we aimed to further characterise the antiviral defence mechanisms in BIE cells by evaluating the innate immune response triggered by rotavirus (RV) infection. In addition, we attempted to determine whether immunobiotic bifidobacteria are able to confer protection of BIE cells against RV infection by beneficially modulating the antiviral immune response. RV OSU (porcine) and UK (bovine) effectively infected BIE cells, while a significant lower capacity to infect BIE cells was observed for human (Wa) and murine (EW) RV. We observed that viral infection in BIE cells triggered TLR3/RIG-I-mediated immune responses with activation of IRF3 and TRAF3, induction of interferon beta (IFN-ß) and up-regulation of inflammatory cytokines. Our results also demonstrated that preventive treatments with Bifidobacterium infantis MCC12 or Bifidobacterium breve MCC1274 significantly reduced RV titres in infected BIE cells and differentially modulated the innate immune response. Of note, both strains significantly improved the production of the antiviral factor IFN-ß in RV-infected BIE cells. In conclusion, this work provides comprehensive information on the antiviral immune response of BIE cells against RV, that can be further studied for the development of strategies aimed to improve antiviral defences in bovine intestinal epithelial cells. Our results also demonstrate that BIE cells could be used as a newly immunobiotic evaluation system against RV infection for application in the bovine host.

Modulation of porcine intestinal epitheliocytes immunetranscriptome response by Lactobacillus jensenii TL2937.

In order to evaluate probiotic strains applicable for the beneficial immunomodulation of the porcine gut (immunobiotics), we previously developed a porcine intestinal epitheliocyte cell line (PIE cells). Here, transcriptomic studies using PIE cells were performed considering that this information would be valuable for understanding the mechanisms involved in the protective activity of the immunobiotic strain Lactobacillus jensenii TL2937 against intestinal inflammatory damage in pigs. In addition, those studies would provide criteria for selecting biomarkers for the screening of new immunobiotic strains. We performed microarray analysis to investigate the transcriptomic response of PIE cells to the challenge with heat-stable enterotoxigenic Escherichia coli (ETEC) pathogen-associated molecular patterns (PAMPs) and, the changes induced by L. jensenii TL2937 in that response. The approach allowed us to obtain a global overview of the immune genes involved in the response of PIE cells to heat-stable ETEC PAMPs. We observed that L. jensenii TL2937 differently modulated gene expression in ETEC PAMPs-challenged PIE cells. Microarray and RT-PCR analysis indicated that the most remarkable changes in PIE cells transcriptomic profile after heat-stable ETEC PAMPs challenge were observed in chemokines, adhesion molecules, complement and coagulation cascades factors. In addition, an anti-inflammatory effect triggered by TL2937 strain in PIE cells was clearly demonstrated. The decrease in the expression of chemokines (CCL8, CXCL5, CXCL9, CXCL10, and CXCL11), complement (C1R, C1S, C3, and CFB), and coagulation factors (F3) by L. jensenii TL2937 supports our previous reports on the immunoregulatory effect of this strain. These results provided clues for the better understanding of the mechanism underlying host-immunobiotic interaction in the porcine host. The comprehensive transcriptomic profiles of PIE cells provided by our analyses successfully identified a group of genes, which could be used as prospective biomarkers for the screening and evaluation of new anti-inflammatory immunobiotics for the prevention of inflammatory intestinal disorders in pigs.

Role of hyperfine coupling in magnetic and quadrupolar ordering of Pr3Pd20Si6.

We study the ternary clathrate Pr3Pd20Si6 in specific heat and ac susceptibility measurements on a high-quality single crystal, distinguishing antiferromagnetic and antiferroquadrupolar ordering, as well as a hitherto unknown magnetic low-temperature transition. The specific heat shows the direct involvement of nuclear spin degrees of freedom in the antiferromagnetic ordering, which is well supported by our calculation of the hyperfine level scheme without adjustable parameters. Pr3Pd20Si6 is, therefore, one of the rare materials where the nuclear moments are involved in the formation of the magnetic ground state.

Magnetic phase diagram of clathrate compound Ce3Pd20Si6 with quadrupolar ordering.

We present results of specific heat measurements on a Ce3Pd20Si6 single crystal and construct the magnetic phase diagram for the three cubic principal directions [100], [110] and [111]. The highly anisotropic phase diagram is discussed and can be qualitatively explained by the Zeeman splitting at the 8c-site. For B â€– [100], the present study found two different quadrupolar ordered phases, which meet the paramagnetic phase at a tri-critical point and establish the new phase boundaries.

New screening methods for probiotics with adhesion properties to sialic acid and sulphate residues in human colonic mucin using the Biacore assay.

AIMS: To determine the relationship between adhesive ability of probiotics and acidic residues in human colonic mucin, we developed a new screening method using Biacore to evaluate adherence of bacteria before and after sialic acid or sulphate residues were blocked or removed from mucin. METHODS AND RESULTS: Ten strains of lactobacilli and three strains of bifidobacteria isolated from human faeces were evaluated for their adhesive properties to soluble human colonic mucin (sHCM) using the Biacore binding assay. Three strains (Lactobacillus strain ME-522, Lact. gasseri ME-527 and Bifidobacterium bifidum MCC1092) showing significant adherence were selected. Decreased binding activities were observed after removing sialic acid of sHCM using sialidase. However, after removing the sulphate residue using sulphatase, the adhesion of ME-527 decreased; whereas the remaining two strains had increased adhesion. The adhesion of three probiotics significantly decreased after the sulphate residue was blocked by elution with barium chloride. CONCLUSIONS: A new evaluation method using the Biacore assay was developed to observe binding properties to the acidic residues of sHCM. Results indicated that there was a strong relationship between probiotic adhesion and acidic residues of sHCM. SIGNIFICANCE AND IMPACT OF THE STUDY: This is the first report showing a screening method that quantitatively measures the binding between bacteria and acidic residues in sHCM using the Biacore binding assay; and provides a new method for the selection of probiotics in the future.

Identification of a new adhesin-like protein from Lactobacillus mucosae ME-340 with specific affinity to the human blood group A and B antigens.

AIMS: To identify and characterize a new adhesin-like protein of probiotics that show specific adhesion to human blood group A and B antigens. METHODS AND RESULTS: Using the BIACORE assay, the adhesion of cell surface components obtained from four lactobacilli strains that adhered to blood group A and B antigens was tested. Their components showed a significant adhesion to A and B antigens when compared to the bovine serum albumin (BSA) control. The 1 mol l(-1) GHCl fraction extracted from Lactobacillus mucosae ME-340 contained a 29-kDa band (Lam29) using SDS-PAGE. The N-terminal amino acid sequence and homology analysis showed that Lam29 was 90% similar to the substrate-binding protein of the ATP-binding cassette (ABC) transporter from Lactobacillus fermentum IFO 3956. The complete nucleotide sequence (858 bp) of Lam29 was determined and encoded a protein of 285 amino acid residues. Phylogenetic analysis and multiple sequence alignments indicated this protein may be related to the cysteine-binding transporter. CONCLUSIONS: The adhesion of ME-340 strain to blood group A and B antigens was mediated by Lam29 that is a putative component of ABC transporter as an adhesin-like protein. SIGNIFICANCE AND IMPACT OF THE STUDY: Lactobacillus mucosae ME-340 expressing Lam29 may be useful for competitive exclusion of pathogens via blood group antigen receptors in the human gastrointestinal mucosa and in the development of new probiotic foods.

HPLC purification and re-evaluation of chemical identity of two circular bacteriocins, gassericin A and reutericin 6.

AIM: The study aimed for the complete purification and recharacterization of the highly hydrophobic circular bacteriocins, gassericin A and reutericin 6. METHODS AND RESULTS: Gassericin A and reutericin 6 were purified to homogeneity using previously described method and reverse-phase HPLC with an octyl column and eluents of aqueous acetonitrile and 2-propanol. Mass analysis, N-terminal sequencing and bacteriocin assay of the HPLC-purified bacteriocins showed the two bacteriocins had identical seamless circular structures with the same m/z value (5651) of [M + H](+) and both had the same specific activity. D/L-amino acid composition analysis using two distinct methods with the chiral fluorescent derivatization reagents (+)-1-(9-fluorenyl)ethyl chloroformate and O-phthalaldehyde/N-acetyl-L-cystein revealed neither gassericin A nor reutericin 6 contained D-alanine residues contrary to our previous results. CONCLUSION: Purified gassericin A and reutericin 6 are chemically identical circular molecules containing no D-alanine residues. SIGNIFICANCE AND IMPACT OF THE STUDY: The HPLC conditions developed in this study will facilitate advanced purification and correct characterization of other highly hydrophobic bacteriocins.

Specific-heat study of the Ce(1 - x)Y(x)PdAl system.

We report on specific-heat measurements of the heavy-fermion compounds Ce(1 - x)Y(x)PdAl (0 ≤ x ≤ 1) between 0.35 and 300 K and in magnetic fields up to 14 T. Ce(1 - x)Y(x)PdAl compounds crystallize in the hexagonal ZrNiAl-type structure and CePdAl orders antiferromagnetically below T(N) = 2.8 K. The specific heat measured in external magnetic fields is also consistent with the antiferromagnetic order and the phase transition to the ferromagnetic state in fields around 4 T. The temperature dependence of the magnetic specific heat in CePdAl indicates magnetic correlations far above T(N). Substitution of nonmagnetic Y for magnetic Ce ions reduces T(N) rapidly and the antiferromagnetic order vanishes around x = 0.2. The Sommerfeld coefficient γ of the electronic specific heat is temperature dependent and increases strongly at low temperatures for all Ce concentrations.

Immunomodulation in gut-associated lymphoid tissue of neonatal chicks by immunobiotic diets.

Developmental changes in immunocompetent cells of the gut during the first week posthatch were determined in broiler chicks fed immunobiotic lactic acid bacteria in the form of Lactobacillus jensenii TL2937-, Lactobacillus gasseri JCM1131(T)-, Lactobacillus delbrueckii ssp. bulgaricus NIAIB6-, or L. gasseri TL2919-supplemented diets. The relative weights of spleen and bursa of Fabricius in chicks fed the immunobiotic diets were slightly higher than the control valued at 1 and 3 d of age, with the exception of spleen weight in the L. gasseri JCM1131(T) at 3 d of age, the bursa of Fabricius weight in the L. gasseri JCM1131(T) at 1 and 3 d of age, and bursa of Fabricius weight in the L. gasseri TL2919 group at 1 d of age. There were no significant differences in body and liver weights among the treatments. When chicks were fed the L. jensenii TL2937- or L. gasseri TL2919-supplemented diets, expression of T cell-related mRNA [cluster of differentiation 3 (CD3), interleukin-2 (IL-2), and interferon-gamma (IFN-gamma)] in the foregut was significantly higher than that of control chicks at 3 or 7 d of age. Expression levels of toll-like receptor (TLR) mRNA tended to increase in the foregut of chicks fed the immunobiotic diets, except for the L. delbrueckii ssp. bulgaricus NIAIB6, compared with expression levels in control chicks. The Bu-1 mRNA expression levels in the bursa of Fabricius were not affected by the supplementations with immunobiotic lactic acid bacteria. These results show that immunobiotics, particularly L. gasseri TL2919, might be useful as immunomodulators to stimulate the gut-associated immune system in neonatal chicks, and thereby protect them from disease without decreasing growth performance as a possible substitution of antibiotics.