Spin-Wave Driven Bidirectional Domain Wall Motion in Kagome Antiferromagnets.

We predict a mechanism to controllably manipulate domain walls in kagome antiferromagnets via a single linearly polarized spin-wave source. We show by means of atomistic spin dynamics simulations of antiferromagnets with kagome structure that the speed and direction of the domain wall motion can be regulated by only tuning the frequency of the applied spin wave. Starting from microscopics, we establish an effective action and derive the corresponding equations of motion for the spin-wave-driven domain wall. Our analytical calculations reveal that the coupling of two spin-wave modes inside the domain wall explains the frequency-dependent velocity of the spin texture. Such a highly tunable spin-wave-induced domain wall motion provides a key component toward next-generation fast, energy-efficient, and Joule-heating-free antiferromagnetic insulator devices.

Enteric permeability and inflammation associated with day of hatch Enterobacteriaceae inoculation.

Early exposure to Enterobacteriaceae may result in inappropriate microbial colonization of the gastrointestinal (GI) tract, induce mild GI inflammation, alter immune system development, and predispose poultry to opportunistic infection. Four experiments were conducted to test Enterobacteriaceae isolates Escherichia coli LG strain (LG), E. coli Huff strain (Huff), Salmonella Enteritidis LB (SE) and Salmonella Typhimurium (ST) on ability to induce GI inflammation. All 4 experiments included a noninoculated control, and day of hatch (DOH) oral inoculation of LG, Huff, SE and ST in experiment 1, LG and SE in experiment 2, and LG, Huff, SE, and ST in experiment 3. Experiment 4 included LG, Huff, a noninoculated control (NIC), and Clostridium perfringens only (NCP) wherein birds received oral C. perfringens challenge on d15-16 to induce necrotic enteritis. Body weight was measured, yolk sacs and spleens were collected, and blood was obtained for serum fluorescein isothiocyanate dextran (FITC-d) recovery and alpha-1-acid glycoprotein (A1GP) concentrations. Samples were taken weekly through 2 wk of age in experiments 1 and 2, or 4 wk of age in experiments 3 and 4. Increased FITC-d recovery was observed for LG and SE on d13 in experiment 2 (P < 0.05), and C. perfringens only birds on d27 in experiment 4 (P < 0.05) as compared to noninoculated controls. Each experiment resulted in notable differences in A1GP serum concentrations over time, with fluctuations in A1GP patterns through d14 based on DOH inoculation (P < 0.05). Over time, A1GP was increased for DOH inoculated birds from d 22 to 29, the fourth wk of life, and d 2-29, the entire experiment, vs. noninoculated controls in experiment 3 (P < 0.05). Similarly, NCP and LGCP showed increased A1GP from d 20 to 27 and d 6 to 27, vs. NIC in experiment 4 (P < 0.05). In experiment 4, C. perfringens challenge resulted in earlier A1GP response in DOH inoculated birds, d 17-20, as compared to NCP birds, d 20-27 (P < 0.05). These results suggest early Enterobacteriaceae exposure may influence early inflammatory state in the GI tract and may also alter patterns of inflammation and responsiveness to pathogens.

Evaluation of day of hatch exposure to various Enterobacteriaceae on inducing gastrointestinal inflammation in chicks through two weeks of age.

Inappropriate microbial colonization can induce gastrointestinal (GI) inflammation may predispose poultry to opportunistic infections and reduce growth performance. Four independent experiments were completed to test ability of select Enterobacteriaceae isolates to induce GI inflammation. Experiments 1 and 2 included a non-inoculated control (NC), and a low (L), medium (M), or high (H) day of hatch (DOH) oral inoculation level. In experiment 1, birds in L1, M1, and H1 received 102 to 104 CFU of a mixed dose of 2 species of Citrobacter and Salmonella Enteritidis LB (SE). In experiment 2, birds in L2, M2, and H2 received 103 to 105 CFU of E. coli LG (LG) and included NC. Body weight was recorded on d 0, 7, and 14, with blood collected for chicken serum alpha-1-acid glycoprotein (A1GP) measurements on d14. Neither experiment resulted in differences in BWG, however, A1GP was increased (P < 0.05) on d 14 when DOH inoculation dose 103 CFU/chick was used compared to NC. This observed increase in A1GP resulted in selection of 103 CFU/chick for DOH inoculation in experiments 3 and 4. Experiment 3 consisted of NC, E. coli Huff (Huff), and SE. On d 0, 7 and 15, BW was measured, with blood collected on d 15 for A1GP. Both d 15 A1GP and BWG from d 7 to 15 were reduced in inoculated chicks, Huff and SE, in experiment 3 (P < 0.05). Experiment 4 evaluated NC and LG with BW measured on d 0, 2, 7 and 14. Yolk sacs were evaluated for retention and bacterial enumeration, and blood for serum A1GP were collected on d 2 and 14. Experiment 4 resulted in no differences in yolk sac parameters or A1GP, whereas there was an increase in BWG for LG from d 0 to 14 (P < 0.05). When evaluated over time, serum A1GP increased between d 2 and d 14 by nearly 46% in LG, compared to negligible changes in NC (P = 0.111). Mild GI inflammation induced by early Enterobacteriaceae exposure may not drastically impact growth or inflammation parameters but may increase susceptibility to opportunistic infection necessitating further study of this model.

Impact of in ovo administered pioneer colonizers on intestinal proteome on day of hatch.

Pioneer colonization of the gastrointestinal tract (GIT) by bacteria is thought to have major influence on neonatal tissue development. Previous studies have shown in ovo inoculation of embryos with saline (S), species of Citrobacter (C, C2), or lactic acid bacteria (L) resulted in an altered microbiome on day of the hatch (DOH). The present study investigated GIT proteomic changes at DOH in relation to different inoculations. Embryos were inoculated in ovo with S or ∼102 cfu of C, C2, or L at 18 embryonic days. On DOH, the GIT was collected, and tissue proteins were extracted for analysis via tandem mass spectrometry. A total of 493 proteins were identified for differential comparison with S at P ≤ 0.10. Different levels were noted in 107, 39, and 78 proteins in C, C2, and L groups, respectively, which were uploaded to Ingenuity Pathway Analysis to determine canonical pathways and biological functions related to these changes. Three members of the cytokine family (interleukin [IL]-1ß, IL6, and Oncostatin M) were predicted to be activated in C2, indicated with Z-score ≥ 1.50, which suggested an overall proinflammatory GIT condition. This was consistent with the activation of the acute-phase response signaling pathway seen exclusively in C2 (Z-score = 2.00, P < 0.01). However, activation (Z-score = 2.00) of IL-13, upregulation of peroxiredoxin-1 and superoxide dismutase 1, in addition to activation of nitric oxide signaling in the cardiovascular system of the L treatment may predict a state of increased antioxidant capacity and decreased inflammatory status. The nuclear factor erythroid 2-related factor 2 (NRF2)-mediated oxidative stress response (Z-score = 2.00, P < 0.01) was predicted to be upregulated in C which suggested that chicks were in an inflammatory state and associated oxidative stress, but the impact of these pathways differed from that of C2. These changes in the proteome suggest that pioneer colonizing microbiota may have a strong impact on pathways associated with GIT immune and cellular development.

A Proteomic View of the Cross-Talk Between Early Intestinal Microbiota and Poultry Immune System.

Proteomics has been used to investigate cross-talk between the intestinal microbiome and host biological processes. In this study, an in ovo technique and a proteomics approach was used to address how early bacterial colonization in the gastrointestinal tract (GIT) could modulate inflammatory and immune responses in young broilers. Embryos at 18 embryogenic days were inoculated with saline (S), 102 CFU of Citrobacter freundii (CF), Citrobacter species (C2), or lactic acid bacteria mixture (L) into the amnion. At 10 days posthatch, ileum samples from 12 birds per treatment were selected for tandem mass spectrometry analysis. Our further findings indicated that treatment-specific influences on early GIT microbiota resulted in different immune responses in mature broilers. Predicted functional analyses revealed activation of inflammation pathways in broilers treated in ovo with L and CF. Exposure to L enhanced functional annotation related to activation, trafficking of immune cells, and skeletal growth based-network, while CF inhibited biological functions associated with immune cell migration and inflammatory response. These results highlighted that proper immune function was dependent on specific GIT microbiota profiles, in which early-life exposure to L-based probiotic may have modulated the immune functions, whereas neonatal colonization of Enterobacteriaceae strains may have led to immune dysregulation associated with chronic inflammation.

Evaluation of the impact of in ovo administered bacteria on microbiome of chicks through 10 days of age.

Initial inoculation and colonization of the chicken gastrointestinal tract (GIT) by microbiota have been suggested to have a major influence on the growth performance and health of birds. Commercial practices in chicken production may alter or delay microbial colonization by pioneer colonizing bacteria that can have an impact on the development and maturation of the GIT and intestinal microflora. The objective of this study was to compare the impact of apathogenic Gram-negative isolates or lactic acid bacteria (LAB) as pioneer colonizers on the microbiome at the day of hatch (DOH) and evaluate the influence through 10 D of age on ceca. At 18 embryonic days (E), the amnion of embryos was inoculated with either saline (S), approximately 102 CFU of LAB (L), Citrobacter freundii (C), or Citrobacter species (C2). Once DNA was isolated from mucosal and digesta contents, samples underwent 2 × 300 paired-end Illumina MiSeq library preparation for microbiome analysis. An increased abundance of Lactobacillaceae family and Lactobacillus genus was observed in the L group at DOH (P < 0.05), whereas the abundance of Enterococcaceae and Enterococcus was numerically decreased. While Lactobacillus salivarius was one of the pioneer colonizers in the L group at 18E, the population decreased by 10 D (39.59 to 0.09%) and replaced with a population of undefined Lactobacillus (10.36%) and Lactobacillus reuteri (3.63%). Results suggest that L treatment may have accelerated a mature microbiota. Enterobacteriaceae was the dominant family (57.44%) in C group at DOH (P < 0.05). The C2 group only showed some abundance of the C2 species (7.92%) at DOH but had the highest overall abundance of undefined Lactobacillus in the ceca by 10 D (25.28%). Taken together, different isolates provided in ovo can have an impact on the initial microbiome of the GIT, and some of these differences in ceca remain notable at 10 D.

Metabolism of broilers subjected to different lairage times at the abattoir and its relationship with broiler meat quality / Metabolismo de frangos de corte submetidos a diferentes tempos de espera no abatedouro e sua relação com a qualidade da carne

An investigation was made into the effects of different lairage times and the position of chicken crates during transport to the slaughterhouse on the biochemical and hematological profile and physical parameters of broilers, such as color and pH of their breast meat. The treatments were defined by the animals slaughtered after 0, 2, 4 and 6 hours of lairage time at the slaughterhouse, transported in crates located in the top and bottom layers of the truck. It was found that increasing the lairage time at the slaughterhouse to over two hours reduced the number of lymphocytes and increased the heterophil/lymphocyte (H/L) ratio and the basophil count in the hemogram. In addition, lactate dehydrogenase (LDH) activity and cholesterol levels increased and plasma triglyceride and glucose levels decreased. The position of the crates in the truck altered the creatine kinase (CK) activity, and the highest enzyme activity was found in birds transported in the top layer of crates in the truck. Furthermore, the long lairage time in the slaughterhouse increased the pH and the value of a* (redness value) and decreased the lightness value of breast fillets. The interaction significant between 4 and 6 hours of lairage time and the position of the crate in the top layer of the truck favored the development of dark, firm, dry (DFD) meat.(AU)

Este trabalho objetivou a avaliação dos efeitos dos diferentes tempos de espera e da posição das caixas de transporte no caminhão sobre perfil bioquímico e hematológico, além de parâmetros físicos da carne, como cor e pH do peito, de frangos de corte. Os tratamentos foram definidos pelos animais abatidos com zero, duas, quatro e seis horas de espera no abatedouro, posicionados nas partes superior e inferior do caminhão. Como resultado, verificou-se que o aumento do tempo de espera no abatedouro, acima de duas horas, resultou em redução no número de linfócitos, elevação da razão heterófilos/ linfócitos (H/L) e de basófilos no hemograma. Houve aumento da atividade de lactato desidrogenase (LDH), dos níveis de colesterol e redução de triglicerídeos e glicose no plasma. O posicionamento das caixas na parte superior da carroceria do caminhão elevou a enzima creatina quinase (CK) sanguínea. Além disso, o tempo prolongado na área de espera aumentou o pH final e o valor de a* (teor de vermelho) e diminuiu a luminosidade dos filés. A interação significante dos fatores tempo de espera de quatro e seis horas e a posição superior das caixas de transporte propiciaram o desenvolvimento de carnes duras, firmes e escuras (DFD) em frangos de corte.(AU)

Paracoccidioides brasiliensis killing by IFN-gamma, TNF-alpha and GM-CSF activated human neutrophils: role for oxygen metabolites.

Paracoccidioidomycosis, a deep mycosis endemic in Latin America, is a chronic granulomatous disease caused by the fungus Paracoccidioides brasiliensis. Phagocytic cells play a critical role against the fungus and several papers show the effects of activator and suppressive cytokines on macrophage and monocyte functions. However, the studies focusing on polymorphonuclear neutrophils (PMNs) antifungal functions are scarcer. Thus, the objective of the present paper was to assess the capacity of human PMNs to kill virulent P. brasiliensis strain in vitro, before and after priming with different cytokines. Moreover, the involvement of oxygen metabolites in this activity was evaluated. Nonactivated cells failed to exhibit antifungal activity. However, when these cells were IFN-gamma, TNF-alpha or GM-CSF activated, a significative fungicidal activity was detected. This process was significantly inhibited when P. brasiliensis challenge occurred in presence of catalase (CAT - a scavenger of H2O2) and superoxide dismutase (SOD - a scavenger of superoxide anion). From these results it is concluded that cytokines activation is required for P. brasiliensis killing by human PMNs, and that H2O2 and superoxide anion participate as effectors molecules in this process.