Giant cell arteritis with stroke and systemic diffuse vasculitis

Giant cell arteritis (GCA) is a systemic vasculitis, which mainly affects the aorta and its branches, while the abdominal aorta, the iliac artery and the limbs involvement are rare. The common clinical manifestations include headache, fever, jaw claudication, and visual impairment. Cerebrovascular accidents are relatively rare. Here, we present a GCA patient with stroke and systemic diffuse vasculitis involving the abdominal aorta, iliac artery, and femoral artery simultaneously.

The Association between Dietary Magnesium Intake and Telomere Length in Adults with Hypertension

BACKGROUND

Dietary micronutrients are significantly associated with telomere length, as shown in multiple studies. However, no study has investigated the association between magnesium intake and telomere length in adults with hypertension.

METHODS

Participants were included from the National Health and Nutrition Examination Survey (NHANES) in 1999-2000 and 2001-2002. Dietary magnesium intake was assessed using the 24 - hour recall method and the telomere length of leukocytes was measured using polymerase chain reaction (PCR). A multivariate regression model was then used to assess the association between dietary magnesium intake and telomere length in adults with hypertension.

RESULTS

Our final analysis included 2199 hypertensive adults (46.79% males) with a mean dietary magnesium intake of 254.82±133.47 mg/day. Linear regression, adjusted for race, sex, age, smoking, uric acid, and other variables, showed that every 1 mg increase in dietary magnesium intake was associated with a 0.20 (95% CI: 0.01, 0.39, p = 0.043) longer telomere length in all participants. In the ≥45 years age group, there was a statistically significant association between the telomere length and dietary magnesium (95% CI: 0.16, 0.63, p <0.001).

CONCLUSIONS

This study suggests that increased magnesium intake is associated with a longer telomere length in hypertensive adults, especially in those ≥45 years of age. However, further research is needed to determine a causal relationship.

Measurement of the Sixth-Order Cumulant of Net-Proton Multiplicity Distributions in Au+Au Collisions at sqrt[s_{NN}]=27, 54.4, and 200 GeV at RHIC

According to first-principle lattice QCD calculations, the transition from quark-gluon plasma to hadronic matter is a smooth crossover in the region μ_{B}≤T_{c}. In this range the ratio, C_{6}/C_{2}, of net-baryon distributions are predicted to be negative. In this Letter, we report the first measurement of the midrapidity net-proton C_{6}/C_{2} from 27, 54.4, and 200 GeV Au+Au collisions at the Relativistic Heavy Ion Collider (RHIC). The dependence on collision centrality and kinematic acceptance in (p_{T}, y) are analyzed. While for 27 and 54.4 GeV collisions the C_{6}/C_{2} values are close to zero within uncertainties, it is observed that for 200 GeV collisions, the C_{6}/C_{2} ratio becomes progressively negative from peripheral to central collisions. Transport model calculations without critical dynamics predict mostly positive values except for the most central collisions within uncertainties. These observations seem to favor a smooth crossover in the high-energy nuclear collisions at top RHIC energy.

[Molecular characteristics of Legionella pneumophila in shower water of public places in Ma'anshan city from 2019 to 2020]

Objective: To understand the epidemiological and pathogenic characteristics of Legionella pneumophila in shower water of public places in Ma'anshan City from 2019 to 2020, and to provide scientific basis for further prevention and control of legionellosis. Methods: From 2019 to 2020, according to population density distribution and business scale of bathing places in the main urban area of Ma'anshan City (Huashan District and Yushan District), 8 public bathing places (including 3 large, 3 medium and 2 small) were selected to collect 308 shower water and water storage pool water samples (294 shower water samples and 14 water storage pool water samples). After the collected water samples were treated, cultured, isolated and identified, the type characteristics of Legionella pneumophila were analyzed. Results: Legionella pneumophila were detected in 120 water samples among 308 shower water and water storage pool water samples, with an overall positive rate of 39.0% (120/308). A total of 154 Legionella pneumophila strains were detected, including 10 different serotypes, predominated by serotype 1 (LP1) and serotype 3 (LP3), accounting for 40.9% (63/154) and 22.7% (35/154). Among 154 strains of Legionella pneumophila, 23 strains of Legionella pneumophila were positive for all 14 virulence genes, accounting for 14.9% (23/154), including 19 serotype 1 (LP1) and 4 serotype 8 (LP8). Pulsed field gel electrophoresis (PFGE) cluster analysis of 154 Legionella pneumophila strains showed 60 different patterns. Conclusion: Legionella pneumophila was seriously polluted in the shower water environment of public places in Ma^, anshan City. The serotypes are widely distributed and the virulence of the strains is strong. The results of molecular typing show that these strains have genetic diversity.

Effects of red-osier dogwood extracts on growth performance, intestinal digestive and absorptive functions, and meat quality of broiler chickens

A total of 320 one-day-old Cobb 500 chicks with an initial weight of 48.3 ± 3.3 g·pen−1 were assigned to four dietary treatments with eight replicates provided in three phases for 46 d. The treatments were fed as mash diets and included (1) negative control (NC) corn-soybean basal diet, (2) positive control (PC) basal diet with 30 ppm avilamycin, (3) basal diet supplemented with 1000 ppm red-osier dogwood extracts (RDE1), and (4) basal diet with 3000 ppm red-osier dogwood extracts (RDE2). Results showed reduced jejunal crypt depth in RDE1 and increased villus:crypt ratio in groups (either RDE1 or RDE2) (P < 0.05). Cationic amino acid (AA) transporter mRNA abundance was decreased (P < 0.05) in RDE1, RDE2, and PC treatments, but peptide and neutral AA transporter mRNA abundance were higher (P < 0.05) in RDE2 compared with NC. Apparent ileal digestibility of crude fat was increased in RDE2 and PC compared with NC, whereas AA digestibility was greater in RDE1, RDE2, and PC (P < 0.05). In conclusion, red-osier dogwood had no effect on growth performance, improved the intestinal health and function of broiler chickens, and had no detrimental effects on meat quality.

Effect of dietary energy density and folic acid supplementation on white striping occurrence and growth performance of broiler chickens

Broilers were allocated to eight treatments consisting of two energy levels: normal (NE) and high (HE), and four folic acid (FA) levels (2.2, 5, 10, and 15 ppm). On day 42, two male and two female chickens were euthanized per pen, and white striping (WS) evaluation was performed on the pectoralis major. Birds fed HE diets had reduced (P < 0.05) feed intake and feed conversion rate than those on NE diets. With increasing FA levels, there was reduced (P < 0.05) WS score and increased (P < 0.05) normal breast fillet percentage in female chickens but not in the males. WS scores were higher (P < 0.01) in male chickens than in the females.

Citral alleviates peptidoglycan-induced inflammation and disruption of barrier functions in porcine intestinal epithelial cells

Peptidoglycan (PGN) is a major polymer in bacterial cell walls and may constrain gut functionality and lower intestinal efficiencies in livestock. Citral has been reported to exhibit antibacterial and anti-inflammatory biological activities, improving the gastrointestinal function of swine. However, the protective effect of citral against PGN-elicited cellular responses and possible underlying mechanisms are unknown. In this study, the porcine jejunal epithelial cell line (IPEC-J2) was challenged with PGN from Staphylococcus aureus (S. aureus) or Bacillus subtilis (B. subtilis) to explore PGN-induced inflammatory responses. Our data showed that the inflammatory response stimulated by PGN from harmful bacteria (S. aureus) was more potent than that from commensal bacteria (B. subtilis) in IPEC-J2 cells. Based on the inflammatory model by PGN from S. aureus, it was demonstrated that PGN could significantly induce inflammatory cytokine production and influence nutrient absorption and barrier function in a dose-dependent manner. However, the PGN-mediated immune responses were remarkably suppressed by citral. In addition, citral significantly attenuated the effect of PGN on the intestine nutrient absorption and barrier function. The expression of TLR2 was strongly induced by PGN stimulation, which was suppressed by citral. All data nominated that citral downregulated PGN-induced inflammation via TLR2-mediated activation of the NF-κB signaling pathway in IPEC-J2 cells. Furthermore, the results also indicate that the PGN degradation through the inclusion of enzymes (e.g., muramidase) as well as the inclusion of citral for attenuating inflammation may improve pig gut health and functionality.

[The prevalence, influencing factors and prognosis of abnormal serum potassium levels in patients with chronic kidney disease]

Objective: To estimate the prevalence of hyperkalemia and hypokalemia in patients with chronic kidney disease (CKD), analyze the influencing factors and explore the impact on disease prognosis. Methods: A total of 3 190 patients with CKD stage 1-4 from 39 tertiary clinical centers in China between November 2011 and December 2016 were recruited. The baseline characteristics of the patients were collected through face-to-face questionnaire investigation, physical examination and laboratory test. Meanwhile, the data of patient's end-stage renal disease, cardiovascular disease events and deaths were obtained up to December 2017 through active monitoring. The patients were categorized into three groups based on their baseline level of serum potassium (hypokalemia:<3.5 mmol/L, normal range: 3.5-<5.0 mmol/L, hyperkalemia: ≥5 mmol/L). Multi-nominal logistic regression was employed to evaluate the association between clinical characteristics and the presence of hyperkalemia or hypokalemia. The competing risk-based subdistribution Cox proportional hazards regression was used to assess the association between baseline level of serum potassium and various outcomes. Results: The mean age of the patients was (50±14) years, with a male rate of 57.6% (1 839/3 190) and a majority of glomerulonephritis (59.7%, 1 668/2 792). Patients with CKD stage 3-4 accounted for 70.8% (2 260/3 190), and the mean level of serum potassium was (4.4±0.7) mmol/L. The prevalence of hypokalemia and hyperkalemia was 3.7% (n=118) and 17.6% (n=561), respectively. In the multivariable adjusted analysis, presence of history of cardiovascular disease (OR=0.33, 95%CI: 0.13-0.83, P=0.019) and estimated glomerular filtration rate (OR=0.95, 95%CI: 0.91-0.98, P=0.001) were inversely associated with hypokalemia, while use of thiazide or loop diuretic (OR=2.06, 95%CI: 1.51-2.81, P<0.001) and estimated glomerular filtration rate (OR=1.13, 95%CI: 1.12-1.16, P<0.001) were positively associated with hyperkalemia. After adjusting for relevant cardiovascular and renal risk factors, the result only showed a significant association between hypokalemia and risk of all-cause mortality (HR=2.12, 95%CI: 1.06-4.24, P=0.034). Conclusions: Hypokalemia and hyperkalemia were not rare in patients with CKD in China, with the latter more prevalent. Hypokalemia was independently associated with the risk of death.

Dietary supplementation of red-osier dogwood polyphenol extract changes the ileal microbiota structure and increases Lactobacillus in a pig model

Red-osier dogwood (ROD) extract contains a lot of polyphenols that have the potential for modulation of gut microbiota. However, little information is available about its prebiotic properties. This study investigated the impact of ROD polyphenol extract on the ileal microbiota with dietary supplementation of ROD polyphenol extract in a pig model. The data indicated that supplementation of ROD polyphenol extract significantly increased class Bacilli, order Lactobacillales and family lactobacillaceae. Within family lactobacillaceae, Lactobacillus was the main responder by increasing from 5.92% to 35.09%. Further analysis showed that ROD polyphenol extract improved two species Lactobacillus delbrueckii and Lactobacillus mucus. The results of this study suggested that ROD polyphenol extract has the potential to play prebiotic role and confer health benefit through modifying gut microbiota.

Validity of near-infrared light transillumination for the assessment of proximal caries in permanent teeth

PURPOSE

The aim of this study was to evaluate the performance of DIAGNOcam (DC) in diagnosing proximal caries and to compare its effectiveness with the International Caries Detection and Assessment System (ICDAS) and bitewing radiography (BWR).

METHODS

118 premolars extracted for orthodontic reasons were included and examined using three detection methods and validated by histological sections as the gold standard. The sensitivity, specificity and areas under the ROC curve (Az value) at the outer half enamel (D1), inner half enamel (D2) and dentine (D3) thresholds were compared between different methods.

RESULTS

At all categories, the specificity of DC was almost as high as ICDAS and BWR. DC showed a significantly higher sensitivity (0.68) than both visual (0.33) and radiographic examination (0.47) at the D1 threshold. DC presented the highest Az value (area under the ROC curve) at the D1 and D2 threshold (0.81, 0.86), while BWR showed the greatest Az values at D3 (0.94). Furthermore, DC had the highest association strength with the gold standard (Spearman's ρ = 0.80).

CONCLUSIONS

It can be concluded that DC could detect proximal caries effectively and showed comparable or even better performance than ICDAS and BWR.

Transcriptome analysis of oviduct in laying ducks under different stocking densities

1. High stocking densities can lead to animal stress responses and lead to changes in bird behaviour, egg production and the fertility of laying birds. The oviduct plays a crucial role during the process of laying eggs. Therefore, it is essential to know how high stocking density affects oviduct function.2. In this study, a total of 2,115 differentially expressed genes (DEGs) were identified in duck oviduct tissues between different stocking density groups. These genes are mainly enriched in membrane components, calcium ion binding, cytokine-cytokine receptor interaction and focal adhesion. These pathways were closely related to the formation of eggs. This indicated that secretion and material transport functions of the oviduct are affected under high-density stocking. Further analysis showed that a total of 408 genes related to the transportation process were expressed in the oviduct, of which 96 genes were differentially expressed (LogFC≥1, P < 0.05). Forty-two of these DEGs belonged to the solute carrier family. The data showed that the expression of 31 transcripts was different between the two density groups. Expression of KCNJ15, SLC26A8, and TRPM5 was only seen in the high-density group (8/m²), while ATP13A3 and KCNIP2 were only expressed in the low-density group (4/m²).3. Consequently, high stocking density may affect the expression and splicing of genes related to molecular transport in the oviduct.

[The study of the impact by atractylenolide-1 on inflammatory cytokine, autophagy and apoptosis in alveolar macrophages of silicosis patients]

Objective: To explore the effect of atractylenolide-1 (ATL-Ⅰ) on alveolar macrophages in silicosis patients. Methods: In December 2019, 12 male silicosis patients treated in Beidaihe Sanatorium for Chinese Coal Miners from July to September 2019 were selected by random sampling. Their alveolar macrophages were collected and divided into control group, ATL-Ⅰ group (100 μmol/L) and dimethyl sulfoxide (DMSO) group (100 μmol/L) . The exprossion levels of inflammatory factor interleukin-1β (IL-1β) , interleukin-6 (IL-6) , tumor necrosis factor α (TNF-α) were detected by enzyme-linked immunosorbent assay. The expression levels of autophagy associated protein microtubule associated protein light chain 3 (LC3) , autophagy substrate protein p62, lysosome associated membrane protein 2 (LAMP2) , apoptosis associated protein Cleaved caspase-3, nuclear factor kappa B (NF-κB) and its phosphorylated form (p-NF-κB) were detected by Western blot. Results: Compared with the control group and DMSO group, the expression levels of IL-1β, IL-6, TNF-α in alveolar macrophages decreased significantly in the ATL-Ⅰ group (P<0.05) , and the expression levels of p-NF-κB, the ratio of LC3-Ⅱ/LC3-Ⅰ also decreased significantly in the ATL-Ⅰ group (P<0.05) . However, the expression levels of NF-κB, LAMP2, p62 and Cleaved caspase-3 in the ATL-Ⅰ group were not statistically different from those in the control group and DMSO group (P>0.05) . There was no statistically significant differences in the expression of the above indexes between the control group and DMSO group (P>0.05) . Conclusion: ATL-Ⅰ may reduce the release of inflammatory factors from alveolar macrophages and inhibit the activity of autophagy in silicosis patients, but it may not reduce the level of apoptosis.

[Screening results and genetic analysis of neonatal tetrahydrobiopterin deficiency in Hainan Province from 2007 to 2019]

A total of 1 295 516 dried blood spots were collected from newborns in Hainan Province from 2007 to 2019 who participated in the screening of neonatal diseases, and 43 cases of hyperphenylalaninemia were diagnosed. Among the 43 cases, 8 cases were confirmed to have tetrahydrobiopterin deficiency (4 males and 4 females). The incidence of tetrahydrobiopterin deficiency among newborns in Hainan Province was 6.2/1 million. Six mutations in the PTS gene were detected among 7 cases; the mutations were as follows: c.317C>T, c.286G>A, c.259C>T, c.155A>G, c.84+291A>G and c.83+1777T>G. A homozygous mutation at c.41T>C site of QDPR gene was detected in one case. Overall, it's found that the incidence of tetrahydrobiopterin deficiency in newborn populations in Hainan Province is low, and PTS gene mutations account for the largest proportion of cases of tetrahydrobiopterin deficiency within the study population.

Clinical efficacy of palbociclib-based therapy in women with HR+/HER2- metastatic breast cancer in the real-world setting for Chinese women: a comparison with the IRIS study

OBJECTIVE

This retrospective study aimed to explore the clinical efficacy of palbociclib with endocrine therapy (ET) in women with hormone receptor-positive (HR+)/human epidermal growth factor receptor 2-negative (HER2-) metastatic breast cancer in real-world practice.

PATIENTS AND METHODS

This retrospective study analyzed the medical records of patients to determine treatment outcomes. Progression-free survival (PFS) curves were generated using log-rank tests with the Kaplan-Meier method. Treatment outcomes in Chinese patients were compared with those in patients from the USA, Argentina, Canada, and Europe in the IRIS study.

RESULTS

In total, 69 patients were included in this study. The median PFS was 12.8 months (95% confidence interval: 10.1-15.5). A longer PFS was observed for patients with bone-only metastases, no liver metastases, no previous palliative chemotherapy, no previous palliative ET, and ET sensitivity. The overall response rate was 10.1%, and the clinical benefit rate was 78.3%. Nineteen patients (27.5%) received a reduced dose of palbociclib according to the decision of their physicians. Dose reduction did not affect the clinical efficacy of the combined treatment. Compared with those in the IRIS study, Chinese patients receiving palbociclib-based treatment were younger, and they had fewer bone-only metastases and more visceral and liver metastases. The clinical benefit rate and overall response rate for Chinese patients were lower than those observed for the patients in the IRIS study.

CONCLUSIONS

ET combined with palbociclib treatment was effective and well-tolerated in HR+/HER2- metastatic breast cancer patients in the real-world setting. Earlier use of palbociclib-ET was associated with more clinical benefits in HR+/HER2- metastatic breast cancer.

Study on the effects of quercetin on brain cell apoptosis and HMGB-1 and TLR-4 level in rats with encephalitis

OBJECTIVE

To explore the therapeutic effects of quercetin on rats with encephalitis, especially on cell apoptosis, and the levels of HMGB-1 and TLR-4.

MATERIALS AND METHODS

32 healthy rats were equally assigned into ZC group (healthy group), NY group (encephalitis group), DJ group (60 ml quercetin group), and GJ group (240 ml quercetin group) followed by analysis of cell apoptosis, brain tissue water content, neurons, HMGB-1, TLR-4 and other inflammatory factors.

RESULTS

The ZC group showed normal neuron volume and equitable staining; compared with ZC group, NY group showed neuron volume shrinkage and chromatin condensation; the neuron and color in DJ group were slightly better than NY group; the neuron volume in GJ group increased significantly and chromatin is distributed evenly. TLR-4, IL-4, IL-6, HMGB-1 in ZC and DJ group were significantly lower than those in NY group (p<0.05); IL-4, IL-6, HMGB-1 in GJ group significantly decreased compared with DJ group (p<0.05); MMP-9 enzyme activity in ZC and DJ group was significantly lower than NY group (p<0.05) with lower level in GJ group than DJ group (p<0.05). The water content was higher in brain tissue of NY group than ZC group (p<0.05) and lower in DJ group than NY group (p<0.05) with lower level in GJ group than DJ and NY group (all p<0.05). The hippocampal neurons and cortical neurons in ZC and DJ group were higher than those in NY group (p<0.05) and elevated in GJ group compared with DJ group and NY group (p<0.05).

CONCLUSIONS

Quercetin is effective in treating encephalitis rats possibly through inhibition of neuronal cell apoptosis and level of HMGB-1 and TLR-4.

Capsaicin Attenuates Lipopolysaccharide-Induced Inflammation and Barrier Dysfunction in Intestinal Porcine Epithelial Cell Line-J2

Capsaicin is a spicy, highly pungent, colorless, vanilloid compound found in chili peppers with anti-inflammatory, antioxidant, anti-cancer, and analgesic properties. However, the protective effects of capsaicin on the pig intestine during inflammation are yet to be explored. This study investigated the effects of capsaicin on the gut inflammatory response, intestinal epithelial integrity, and gene expression level of nutrient transporters in a model of lipopolysaccharide (LPS)-induced inflammation in non-differentiated intestinal porcine epithelial cell line-J2 (IPEC-J2). The results showed that the pre-treatment of cells with capsaicin (100 μM) significantly decreased the gene expression and secretion of proinflammatory cytokines induced by LPS through Toll-like receptor 4 (TLR4)/NF-κB signaling pathway. In addition, pre-treatment of cells with capsaicin also increased both gene and protein abundance of tight junction proteins. Furthermore, pre-treatment cells with capsaicin significantly increased trans-epithelial electrical resistance (TEER) and decreased permeability of fluorescein isothiocyanate-dextran (FD4) from the apical side to the basolateral side compared with the control (P < 0.05). Additionally, pre-treatment of cells with capsaicin upregulated the mRNA abundance of nutrients transporters such as Na⁺/glucose cotransporter 1 (SGLT1). These results suggested that capsaicin could attenuate LPS-induced inflammation response through TLR4/NF-κB pathway and improve barrier integrity and glucose absorption.

[Multi-level scanning of environmental factors of body mass index of children and adolescents aged 7-17 years in China]

Objective: To investigate the influence of environmental factors on body mass index of children and adolescents in China. Methods: Using data from the China Health and Nutrition Survey, the research object to 7 - 17 years old children and adolescents who participated in 2000, 2006, 2011, and 2015 round of survey with complete data, a total of 6 626 children and adolescents (male 3 473, female 3 153) were investigated under univariate analysis for each environmental factor variable before using Partial Least Square Regression fitting a linear model for further screening. Finally, we fitted a three-level linear mixed-effects model distinct by urban and rural area for analysis. Results: The three-level null model, log likelihood=-17 034.68, χ²=483.06, P<0.001. Intern-class correlation coefficient (ICC) showed that community-level was 9.97%, and both community and individual were 39.38%. The three-level model also showed that urban model's urbanization index (β=-0.05, 95%CI: -0.09--0.01, P<0.05), the park location (β=-0.88, 95%CI: -1.72 - -0.04, P<0.05), 15 - 17 age group (β=-1.04, 95%CI:-1.78 - -0.30, P<0.05) were negatively correlated with BMI. The distance to the gym (β=0.12, 95%CI: 0.02 - 0.22, P<0.05), the number of home TV sets (β=0.50, 95%CI: 0.08 - 0.92, P<0.05) and the frequency of parents' alarm of fiction TV program contents (β=1.85, 95%CI: 0.70 - 3.00, P<0.05) were correlated with BMI. Rural urbanization index (β=-0.04, 95%CI:-0.07 - -0.01, P<0.05). Rural per capita income (β=-7.29e^-4, 95%CI:-1.00e^-3 - -6.77e^-5, P<0.05), parents' restricted frequency of watching TV (β=-1.29, 95%CI:-2.36 - -0.21, P<0.05), adipo-energy ratio (β=-0.03, 95%CI:-0.06 - -1.00e^-3, P<0.05) were negatively correlated with the BMI. Factors as the frequency of parents' alarm of fiction TV program contents (β=3.01, 95%CI: 0.03 - 6.00, P<0.05), the survey time was 2015 (β=4.83, 95%CI: 1.96 - 7.69, P<0.05) were correlated with BMI. Conclusions: Environmental factors could indirectly influence the change of BMI of children and adolescents to different degrees and various aspects. Urbanization index and rural per capita income had a slight protective effect on increasing BMI of children and adolescents. At the community level, attention should be paid to the setting of activity places around the living environment of children and adolescents. Family members should also guide their children and adolescents to develop nice behavior in watching TV.

154 Virulence Potential of Antimicrobial Resistant Extraintestinal Pathogenic Escherichia coli from Poultry in a Caenorhabditis Elegans Model

This study investigated virulence potential of poultry antimicrobial resistant extraintestinal pathogenic E. coli (ExPEC). A total of 46 E. coli isolates from poultry meat, feces, or humans were sequenced and identified as ExPEC. Based on their characteristics, eight of these ExPEC isolates were evaluated for their potentials using a Caenorhabditis elegans infection model. The life-span of C. elegans in response to these eight isolates was examined in three life-span experiments: 1) E. coli OP 50 (negative control), K88+ enterotoxigenic E. coli strain JG280 (positive control), and an ExPEC isolate from human urinal tract infection; 2) three ExPEC isolates from chicken and turkey retail meats; 3) four ExPEC isolates from chicken feces with different antimicrobial resistance (AMR) profiles or a various number of virulence genes (VGs). All 46 isolates belonged to 24 serotypes among which 6 were of serotype O25:H4 Sequence Type 131 (ST131). Interestingly, all ST 131 isolates from chicken or turkey retail meats clustered with a human UTI isolate belonging to the similar serotype and ST type. The types and numbers of AGRs and VGs varied among the eight selected isolates for C. elegans model. The human ExPEC induced a similar effect as the JG280 on reducing (P &lt; 0.05) survival of C. elegans. Interestingly, chicken and turkey meat ExPEC isolates, caused similar negative impacts on the survival of worms as the human ExPEC. Additionally, fecal ExPEC isolates reduced (P &lt; 0.05) the survival of C. elegans compared to OP50. However, the survival of C. elegans was not reduced with an increasing number of VGs and did not seem to be affected by AMR profiles. This study indicated the virulence potential of ExPEC isolates from retail poultry meat or feces. The relationship between specific AMR profiles and/or numbers of VGs with pathogenicity in these E. coli isolates deserves further investigations.

158 The Identification of Pig Calcium-sensing Receptor (pCaSR) Expression in Porcine Intestinal Enterocytes

Enterocytes play important roles in nutrient absorption, while the intestinal porcine enterocyte cell line (IPEC-J2) is a non-transformed and permanent commercial cell line. The calcium-sensing receptor (CaSR) has been identified as calcium ions and L-amino acids sensor in the gut and studies have demonstrated that the CaSR is involved in nutrient digestion and absorption, as well as gut barrier function. Although the expression of CaSR on the basal membrane of the villus has been found in other animal species, its expression in porcine enterocytes (pCaSR) has not been investigated to date. To investigate the expression of pCaSR in isolated porcine enterocytes and IPEC-J2, cell sorting of ileal enterocytes by fluorescence-activated cell sorting (FACS) based on sucrase-isomaltose as enterocytes marker were performed to obtain pure porcine enterocytes. The digital droplet PCR (ddPCR), immunofluorescence staining, and Western blotting were applied for the detection of pCaSR expression at the gene and protein levels, respectively. Our results showed that about 3.3% of upper epithelial cells were characterized and sorted as pure porcine enterocytes, while the other cells were negative to the enterocytes marker. In addition, neither the isolated porcine enterocytes nor the IPEC-J2 expressed the pCaSR. In summary, pure porcine enterocytes could be obtained by using FACS with the sucrase-isomaltase as enterocytes marker but pCaSR is not expressed in either isolated porcine enterocytes or IPEC-J2, which provides new insights for future work exploring the role of pCaSR in the intestine.

PSIII-21 Efficacy of deoxynivalenol detoxification by sodium metabisulfite (SMBS) containing nanofibrous mats using an in vitro intestinal epithelial cell IPEC-J2

Deoxynivalenol (DON) occurs in many commonly used cereal grains. Pigs feed with DON concentrations as low as 0.6–2.0 mg/kg can result in reduced feed intake and growth rate, damage to intestinal epithelial cells, and increase susceptibility to enteric pathogens. Sodium metabisulfite (SMBS) can efficiently detoxify DON by converting it 8-DONS or 10-DONS in vitro. However, if SMBS is added directly to the feed, SMBS rapidly degrades under acidic aqueous conditions (e.g. pig stomach) and little SMBS is delivered to the intestinal absorption site where it can effectively detoxify DON. Thus, the objective of this study was to encapsulate SMBS into Eudragit L100-55 nanofibrous mats to deliver intact SMBS to the small intestine and evaluate the efficacy of DON detoxification in the simulated intestine fluid (SIF) using an in vitro intestinal epithelial cell (IPEC-J2) model. Nanofibrous mats were produced by coaxial electrospinning, with peak loading capacity and loading efficiency of SMBS reaching 32.00% and 80.01%. DON-induced cytotoxicity was not observed during in vitro analysis consisting of incubation of DON in the presence of SMBS-containing nanofibers (0.5% w/w) in simulated gastric fluid (SGF) for 2 h followed by incubation in a mixture of SGF and SIF (1:1) for 20 min. Meanwhile, compared to the DON treatment, incubation of DON in the presence of SMBS-containing nanofiber (0.5% w/w) in SGF for 2 h and SIF for 20 min decreased the gene expression of inflammatory cytokines in the IPEC-J2 cells and maintained the cell integrity. To conclude, SMBS released from Eudragit L100-55 nanofibrous mats in the SIF effectively decreased the adverse effects induced by DON in the IPEC-J2 cells. Nanofibrous mats can release a large amount of SMBS in a short time in SIF to achieve the effect of detoxifying DON.

217 Comparative Effects of Dietary Methionine and Cysteine Supplementation on Redox Status and Intestinal Integrity in Immunologically Challenged-weaned Pigs

The aim was to investigate the effects of dietary Met and Cys supplementation in immunologically challenged-weaned pigs. Forty weaned piglets (6.51 ± 0.29 kg) were randomly allocated to five treatments and fed the assigned diets for 9 days. The treatments included: (1) sham-challenged control (SCC), (2) challenged control (CC), (3) MET (CC + 0.1% DL-Met supplementation), (4) CYS (CC + 0.1% L-Cys supplementation), and (5) MET+CYS (CC + 0.1% DL-Met and 0.1% L-Cys supplementation). Piglets were intramuscularly injected with either lipopolysaccharides (LPS; 30 μg/kg) or saline solution on day 7. All data were analyzed using single degree of freedom contrasts in the mixed procedure of SAS to test the effect of LPS challenge, Met supplementation, Cys supplementation, and Met × Cys supplementation. The CC group had lower (P &lt; 0.05) villi height and villi surface area and glutathione (GSH) concentration and higher (P &lt; 0.05) flux of 4-kDa fluorescein isothiocyanate dextran (FD4) in the jejunum than SCC group. Dietary Cys supplementation increased (P &lt; 0.05) villi surface area, GSH concentration and reduced GSH: oxidized GSH and decreased (P &lt; 0.05) the flux of FD4 in the jejunum. Dietary Met supplementation enhanced (P &lt; 0.05) hepatic GSH content. Pigs in the MET group had greater mRNA abundance of IL-6 and IL-10 (P &lt; 0.05) and lower serum IL-8 concentration than those in the CC group. There were Met × Cys interactions (P &lt; 0.05) in serum IL-4 and IL-8 concentrations and hepatic Trolox equivalent antioxidant capacity. In conclusion, dietary L-Cys supplementation restored intestinal integrity and GSH concentration that were affected by LPS challenge. Dietary DL-Met supplementation improved hepatic GSH and reduced systemic inflammatory response, but antagonistic interaction with dietary Cys supplementation was observed in inflammatory response and redox status.

159 In vitro Characterization of Potential Pig Calcium-sensing Receptor (CaSR) Ligands and Cell Signaling Pathways Related to CaSR Activation by a Dual-luciferase Reporter Assay

The calcium-sensing receptor (CaSR) is a pivotal regulator of calcium homeostasis. Our previous study has found that pig CaSR (pCaSR) is widely expressed in intestinal segments in weaned piglets. To characterize the activation of pCaSR by potential ligands and related cell signaling pathways, a dual-luciferase reporter assay was employed for the ligands screening and molecular docking was utilized to predict the binding mode of identified ligands. Our results showed that the dual-luciferase reporter assay system was well suited for pCaSR research and its ligand screening. The extracellular calcium activated pCaSR in a concentration-dependent manner with a half-maximal effective concentration (EC50) = 4.74 mM through the Gq/11 signaling pathway, EC50 = 2.85 mM through extracellular signal-regulated kinases 1 and 2 (ERK1/2) activation signaling pathway, and EC50 = 2.26 mM through the Ras homolog family member A (RhoA) activation signaling pathway. Moreover, the activation of pCaSR stimulated by extracellular calcium showed biased agonism through three main signaling pathways: ERK1/2 phosphorylation signaling, Gq/11 signaling, and G12/13 signaling. Both L-Tryptophan and α-casein (90–95) could activate the pCaSR in the presence of extracellular calcium. Furthermore, we characterized the L-tryptophan binding pocket formed by pCaSR residues TRP 70, SER 147, ALA168, SER 169, SER 170, ASP 190, GLU 297, ALA 298, and ILE 416, as well as the α-casein (90–95) binding pocket formed by pCaSR residues PRO188, ASN189, GLU191, HIS192, LYS225, LEU242, ASP480, VAL486, GLY487, VAL513, and TYR514. In conclusion, similar to the human CaSR, the pCaSR also shows biased agonism through three main signaling pathways and both α-casein (90–95) and L-tryptophan are agonists for pCaSR. Furthermore, the binding sites of α-casein (90–95) and L-tryptophan are mainly located within the extracellular domain of pCaSR.