The recently commissioned Linac Coherent Light Source is an X-ray free-electron laser at the SLAC National Accelerator Laboratory. It produces coherent soft and hard X-rays with peak brightness ...nearly ten orders of magnitude beyond conventional synchrotron sources and a range of pulse durations from 500 to <10 fs (10-15 s). With these beam characteristics this light source is capable of imaging the structure and dynamics of matter at atomic size and timescales. The facility is now operating at X-ray wavelengths from 22 to 1.2 A and is presently delivering this high-brilliance beam to a growing array of scientific researchers. We describe the operation and performance of this new 'fourth-generation light source'.
A study was aimed to investigate the effects of mixed Eimeria challenge on performance, gastrointestinal health, oxidative stress, inflammation, and expression of nutrient transporter genes of ...Hy-Line W-36 pullets. A total of 540, 16-d old pullets were randomly allocated into 5 treatment groups with 6 replicate cages, including a nonchallenged control group. A mixed Eimeria species solution containing 50,000 E. maxima, 50,000 E. tenella, and 250,000 E. acervulina oocysts per mL was prepared and challenged to one group as a high-dose treatment (High). The 2-fold serial dilution was done to prepare the medium-high (Med-High: 25,000 E. maxima; 25,000 E. tenella; and 125,000 E. acervulina), the medium-low (Med-Low: 12,500 E. maxima; 12,500 E. tenella; and 62,500 E. acervulina), and the low (Low: 6,250 E. maxima; 6,250 E. tenella; and 31,250 E. acervulina) dose treatments, and these dosages were challenged to 3 remaining groups, respectively. Growth performance, daily feed intake (FI), and mortality were calculated from 0-14 d postinfection (DPI). Gastrointestinal permeability (GP) was measured on 3, 5, 6, 7, and 9 DPI. The result indicated significant linear responses to the Eimeria challenge dosage in average body weight and body weight gain (P < 0.0001). An interaction between treatment and DPI was observed for FI (P < 0.0001). Feed intake significantly dropped from 4 DPI and did not recover until 12 DPI in the challenged groups. The lowest FI for each of the challenged groups was observed on 5 DPI. Gastrointestinal permeability increased linearly, peaking at 5 DPI, and was recovered back to normal by 9 DPI in the challenged groups. Furthermore, gene expression of tight junction proteins was linearly upregulated by increased Eimeria dosages. The oxidative status of the pullets was lowered in the challenged groups than the nonchallenged control group, whereas the expression of inflammatory and proinflammatory cytokines was upregulated by Eimeria challenge on 6 DPI (P < 0.05). The highest mortality was observed in pullets challenged with the High, followed by the Med-High (P < 0.0001) on 5 DPI. In summary, the mixed Eimeria challenge linearly reduced the growth performance of pullets with an increase in oxidative stress and inflammation. A severe effect of Eimeria on gastrointestinal health was observed on 5 or 6 DPI as suggested by GP, tight junction genes, and mortality results. This study indicates that Eimeria infection can be a threat to gastrointestinal health related issues in pullets.
A study was conducted to investigate effects of different methionine (Met) to cysteine (Cys) supplementation ratios (MCR) on growth performance, oxidative status, intestinal health, immune responses, ...and methionine metabolism in broilers under Eimeria challenge. A total of 720 male Cobb500 broilers (14-day-old) were allocated in a 2 × 5 factorial arrangement (5 diets, with or without challenge) with 6 replicates per treatment. The total sulfur amino acid concentrations were consistent across treatments meeting the breeder's recommendation, only MCR varied. The diets were labeled as MET100; MET75; MET50; MET25; and MET0, representing MCR of 100:0; 75:25; 50:50; 25:75; and 0:100, respectively. Data were analyzed by 2-way ANOVA and orthogonal polynomial contrast. Growth performance declined linearly or quadratically as MCR decreased (P < 0.01). On 6-day postinoculation (DPI), interaction effects (P < 0.01) were found; BW and body weight gain were lower in MET0 compared to the other treatments in the nonchallenged groups, whereas not in the challenged groups. On 6 and 9 DPI, serum total antioxidant capacity linearly decreased as MCR decreased (P < 0.05). Hepatic activities of glutathione peroxidase on 6 DPI and superoxide dismutase on 9 DPI changed quadratically as MCR decreased (P < 0.05). The digestibility of Met linearly decreased whereas the digestibility of Cys linearly increased as MCR decreased. The ileal crypt depth linearly decreased as MCR decreased (P < 0.01) on 6 DPI. The expression of transforming growth factor beta on 6 and 9 DPI, tumor necrotic factor alpha and interleukin 10 on 9 DPI changed quadratically as MCR decreased (P < 0.05). Eimeria challenge increased expression of Met adenosyltransferase and cystathionine gamma-lyase, whereas decreasing the expression of other Met metabolism genes (P < 0.01) on 6 DPI. Expression of Met metabolism genes linearly increased as MCR decreased (P < 0.05). In conclusion, different Met to Cys supplementation ratios exerted linearly or quadratically effects on the growth performance, oxidative status, intestinal health, and metabolism of Met in broiler chickens under Eimeria infection.
An experiment was carried out to evaluate the impact of mixed Eimeria challenge on skeletal health of Hy-Line W-36 pullets. A total of 540, 16-day-old pullets were randomly allocated into 5 treatment ...groups, including a nonchallenged control. A mixed Eimeria species solution containing 50,000 E. maxima, 50,000 E. tenella, and 250,000 E. acervulina oocysts per mL was prepared and challenged to 1 group as a high-dose treatment. The 2-fold serial dilution was done to prepare the medium-high (25,000 E. maxima; 25,000 E. tenella; 125,000 E. acervulina), the medium-low (12,500 E. maxima; 12,500 E. tenella; 62,500 E. acervulina), and the low (6,250 E. maxima; 6,250 E. tenella; 31,250 E. acervulina) dose treatments which were challenged to 3 corresponding groups, respectively. The mineral apposition rate (MAR) was measured from 0 to 14 d post inoculation (DPI) and 14 to 28 DPI using calcein injection. The microstructural architecture of the femur was analyzed using the Skyscan X-ray microtomography (microCT) on 6, 14, and 28 DPI. The results showed that the MAR decreased linearly with an increase in the challenged dose (P < 0.05) during 0 to 14 DPI. The results of microCT revealed that cortical and total BMD, BMC, bone volume (BV), and bone volume as a fraction of tissue volume (BV/TV) of femur decreased both linearly (P < 0.05). Conversely, the total number of pores increased linearly with an increase in challenge dosages on 6 and 14 DPI. Trabecular BMD, BV, BV/TV, trabecular number, and trabecular thickness decreased linearly with an increase in the challenge dosages (P < 0.05) on 6 DPI. Furthermore, Eimeria infection significantly increased the number of osteoclasts and osteoclastic activity (P = 0.001). The result of this study suggests that the mixed Eimeria challenge negatively impacts the quality of skeletal health in a linear or quadratic manner with an increase in the concentration of Eimeria oocysts. The negative impact on long bone development might be due to malabsorption, nutrient deficiency during the infection, along with oxidative stress/inflammation disrupting the balance of osteoblastic and osteoclastic cells and their functions.
The bronchioles of the murine lung are lined by a simple columnar epithelium composed of ciliated, Clara, and goblet cells that together mediate barrier function, mucociliary clearance and innate ...host defense, vital for pulmonary homeostasis. In the present work, we demonstrate that expression of Sox2 in Clara cells is required for the differentiation of ciliated, Clara, and goblet cells that line the bronchioles of the postnatal lung. The gene was selectively deleted in Clara cells utilizing Scgb1a1-Cre, causing the progressive loss of Sox2 in the bronchioles during perinatal and postnatal development. The rate of bronchiolar cell proliferation was decreased and associated with the formation of an undifferentiated, cuboidal-squamous epithelium lacking the expression of markers of Clara cells (Scgb1a1), ciliated cells (FoxJ1 and alpha-tubulin), and goblet cells (Spdef and Muc5AC). By adulthood, bronchiolar cell numbers were decreased and Sox2 was absent in extensive regions of the bronchiolar epithelium, at which time residual Sox2 expression was primarily restricted to selective niches of CGRP staining neuroepithelial cells. Allergen-induced goblet cell differentiation and mucus production was absent in the respiratory epithelium lacking Sox2. In vitro, Sox2 activated promoter-luciferase reporter constructs for differentiation markers characteristic of Clara, ciliated, and goblet cells, Scgb1a1, FoxJ1, and Agr2, respectively. Sox2 physically interacted with Smad3 and inhibited TGF-beta1/Smad3-mediated transcriptional activity in vitro, a pathway that negatively regulates proliferation. Sox2 is required for proliferation and differentiation of Clara cells that serve as the progenitor cells from which Clara, ciliated, and goblet cells are derived.
Despite the acknowledged significance of nutrition in bone development, effects of methionine (Met) and cysteine (Cys) on bone quality remain under-researched, particularly during Eimeria challenge. ...We investigated the effects of different supplemental Met to Cys ratios (MCR) on bone quality of broilers under Eimeria challenge. A total of 720 fourteen-day old Cobb500 broilers were allocated into a 5 × 2 factorial arrangement. Five diets with Met and Cys supplemented at MCR of 100:0, 75:25, 50:50, 25:75, and 0:100 were fed to the birds with or without Eimeria challenge. Body composition was measured by dual energy x-ray absorptiometry, and the femur bone characteristics were assessed by microtomography. Data were analyzed by two-way ANOVA and orthogonal polynomial contrast. The results reaffirmed the detrimental effects of Eimeria challenge on bone quality. On 9 d post inoculation (DPI), significant interaction effects were found for whole body bone mineral content (BMC), lean tissue weight, and body weight (P < 0.05); in the nonchallenged group (NCG), these parameters linearly decreased as MCR decreased (P < 0.05). In the challenged group (CG), body weight and lean tissue weight were unaffected by MCR, and BMC linearly increased as MCR decreased (P < 0.05). For the cortical bone of femoral metaphysis on 6 DPI, bone mineral density (BMD) linearly increased as MCR decreased (P < 0.05). Bone volume to tissue volume ratio (BV/TV) in the CG linearly increased as MCR decreased (P < 0.05). On 9 DPI, BMC and TV linearly increased as MCR decreased (P < 0.05) in the NCG. BMD and BV/TV changed quadratically as MCR decreased (P < 0.05). For the trabecular bone of femoral metaphysis on 9 DPI, BV/TV, and trabecular number linearly increased as MCR decreased (P < 0.05) in the NCG. For the femoral diaphysis, BV, TV, BMC on 6 DPI, and BMD on 9 DPI linearly increased as MCR decreased (P < 0.05). In conclusion, this study showed that both Eimeria challenge and varying supplemental MCR could influence bone quality of broilers.
The objective of this study was to evaluate the impact of coccidiosis on bone quality and antioxidant status in the liver and bone marrow of broiler chickens. A total of 360 13-day old male broilers ...(Cobb 500) were randomly assigned to different groups (negative control, low, medium-low, medium-high, and highest dose groups) and orally gavaged with different concentrations of
Eimeria
oocysts solution. Broiler tibia and tibia bone marrow were collected at 6 days post-infection (6 dpi) for bone 3-D structural analyses and the gene expression related to osteogenesis, oxidative stress, and adipogenesis using micro-computed tomography (micro-CT) and real-time qPCR analysis, respectively. Metaphyseal bone mineral density and content were reduced in response to the increase of
Eimeria
challenge dose, and poor trabecular bone traits were observed in the high inoculation group. However, there were no significant structural changes in metaphyseal cortical bone. Medium-high
Eimeria
challenge dose significantly increased level of peroxisome proliferator-activated receptor gamma (
PPARG
,
p
< 0.05) and decreased levels of bone gamma-carboxyglutamate protein coding gene (
BGLAP, p
< 0.05) and fatty acid synthase coding gene (
FASN
,
p
< 0.05) in bone marrow. An increased mRNA level of superoxide dismutase type 1 (
SOD1, p
< 0.05) and heme oxygenase 1 (
HMOX1, p
< 0.05), and increased enzyme activity of superoxide dismutase (SOD,
p
< 0.05) were found in bone marrow of
Eimeria
challenged groups compared with that of non-infected control. Similarly, enzyme activity of SOD and the mRNA level of
SOD1
,
HMOX1
and aflatoxin aldehyde reductase (
AKE7A2
) were increased in the liver of infected broilers (
p
< 0.05), whereas glutathione (GSH) content was lower in the medium-high challenge group (
p
< 0.05) compared with non-challenged control. Moreover, the mRNA expression of catalase (
CAT
) and nuclear factor kappa B1 (
NFKB1
) showed dose-depend response in the liver, where expression of
CAT
and
NFKB1
was upregulated in the low challenge group but decreased with the higher
Eimeria
challenge dosage (
p
< 0.05). In conclusion, high challenge dose of
Eimeria
infection negatively affected the long bone development. The structural changes of tibia and decreased mineral content were mainly located at the trabecular bone of metaphyseal area. The change of redox and impaired antioxidant status following the
Eimeria
infection were observed in the liver and bone marrow of broilers.
This study evaluated the effects of maternal fish oil supplementation rich in n-3 PUFA on the performance and bone health of offspring broilers at embryonic development stage and at market age. Ross ...708 broiler breeder hens were fed standard diets containing either 2.3% soybean oil (SO) or fish oil (FO) for 28 days. Their fertilized eggs were collected and hatched. For a pre-hatch study, left tibia samples were collected at 18 days of incubation. For a post-hatch study, a total of 240 male chicks from each maternal treatment were randomly selected and assigned to 12 floor pens and provided with the same broiler diets. At 42 days of age, growth performance, body composition, bone microstructure, and expression of key bone marrow osteogenic and adipogenic genes were evaluated. One-way ANOVA was performed, and means were compared by student's t-test. Maternal use of FO in breeder hen diet increased bone mineral content (p < 0.01), bone tissue volume (p < 0.05), and bone surface area (p < 0.05), but decreased total porosity volume (p < 0.01) during the embryonic development period. The FO group showed higher body weight gain and feed intake at the finisher stage than the SO group. Body composition analyses by dual-energy X-ray absorptiometry showed that the FO group had higher fat percentage and higher fat mass at day 1, but higher lean mass and total body mass at market age. The decreased expression of key adipogenic genes in the FO group suggested that prenatal FO supplementation in breeder hen diet suppressed adipogenesis in offspring bone marrow. Furthermore, no major differences were observed in expression of osteogenesis marker genes, microstructure change in trabecular bone, or bone mineral density. However, a significant higher close pores/open pores ratio suggested an improvement on bone health of the FO group. Thus, this study indicates that maternal fish oil diet rich in n-3 PUFA could have a favorable impact on fat mass and skeletal integrity in broiler offspring.
In the modern poultry industry, with increasing product demand, muscle growth rate and meat yield in chickens have tremendously changed. Understanding the regulation of muscle development is ...important to maintain efficient growth and development in meat-type chickens. 20(S)-hydroxycholesterol (20S) is known as one of the naturally occurring osteogenic cholesterol derivatives due to its ability to induce osteogenic differentiation; however, no studies have evaluated myogenic response to 20S in chicken muscle cells. To determine the use of 20S in vitro for the proliferation and differentiation of chicken satellite cells, satellite cells were isolated from pectoralis major muscle of 4-week-old Ross 708 male chickens and subjected to 0.25, 0.5, and 1.0 μmol of 20S during their proliferation and differentiation stages. Cell proliferation and differentiation were measured every 24 h for 72 h by determining DNA concentration, the activity of creatine kinase, and the expressions of myogenic regulatory transcription factors. Together these results suggested that a lower concentration of 20S did not affect myogenesis but a high concentration of 1.0 μmol 20S can negatively affect proliferation and differentiation in chicken satellite cells.
The effects of hydrogen peroxide (H
O
) on the osteogenic differentiation of primary chicken mesenchymal stem cells (MSCs) were investigated. MSCs were subjected to an osteogenic program and exposed ...to various concentrations of H
O
for 14 days. Results showed that high concentrations of H
O
(200 and 400 nM) significantly increased pro-apoptotic marker
expression and impaired osteogenic differentiation, as indicated by decreased mRNA expression levels of osteogenesis-related genes and reduced
mineralization. In contrast, long-term H
O
exposure promoted basal expression of adipogenic markers at the expense of osteogenesis in MSCs during osteogenic differentiation, and increased intracellular reactive oxygen species (ROS) production, as well as altered antioxidant enzyme gene expression. These findings suggest that long-term H
O
-induced ROS production impairs osteogenic differentiation in chicken MSCs under an osteogenic program.