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1.
J Korean Med Sci ; 38(27): e205, 2023 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-37431539

RESUMO

Tixagevimab/cilgavimab is a monoclonal antibody used to prevent coronavirus disease 2019 among immunocompromised hosts and maintained neutralizing activity against early omicron variants. Omicron BN.1 became a dominant circulating strain in Korea early 2023, but its susceptibility to tixagevimab/cilgavimab is unclear. We conducted plaque reduction neutralization test (PRNT) against BN.1 in a prospective cohort (14 patients and 30 specimens). BN.1 PRNT was conducted for one- and three-months after tixagevimab/cilgavimab administration and the average PRNT ND50 of each point was lower than the positive cut-off value of 20 (12.9 ± 4.5 and 13.2 ± 4.2, respectively, P = 0.825). In the paired analyses, tixagevimab/cilgavimab-administered sera could not actively neutralize BN.1 (PRNT ND50 11.5 ± 2.9, P = 0.001), compared with the reserved activity against BA.5 (ND50 310.5 ± 180.4). Unlike virus-like particle assay, tixagevimab/cilgavimab was not active against BN.1 in neutralizing assay, and would not be effective in the present predominance of BA.2.75 sublineages.


Assuntos
COVID-19 , Humanos , Estudos Prospectivos , SARS-CoV-2 , Anticorpos Monoclonais , Surtos de Doenças , República da Coreia/epidemiologia
2.
Int J Mol Sci ; 22(14)2021 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-34299130

RESUMO

Although cisplatin is one of most effective chemotherapeutic drugs that is widely used to treat various types of cancer, it can cause undesirable damage in immune cells and normal tissue because of its strong cytotoxicity and non-selectivity. This study was conducted to investigate the cytoprotective effects of Cudrania tricuspidata fruit-derived polysaccharides (CTPS) against cisplatin-induced cytotoxicity in macrophages, lung cancer cell lines, and a mouse model, and to explore the possibility of application of CTPS as a supplement for anticancer therapy. Both cisplatin alone and cisplatin with CTPS induced a significant cytotoxicity in A549 and H460 lung cancer cells, whereas cytotoxicity was suppressed by CTPS in cisplatin-treated RAW264.7 cells. CTPS significantly attenuated the apoptotic and necrotic population, as well as cell penetration in cisplatin-treated RAW264.7 cells, which ultimately inhibited the upregulation of Bcl-2-associated X protein (Bax), cytosolic cytochrome c, poly (adenosine diphosphateribose) polymerase (PARP) cleavage, and caspases-3, -8, and -9, and the downregulation of B cell lymphoma-2 (Bcl-2). The CTPS-induced cytoprotective action was mediated with a reduction in reactive oxygen species production and mitochondrial transmembrane potential loss in cisplatin-treated RAW264.7 cells. In agreement with the results obtained above, CTPS induced the attenuation of cell damage in cisplatin-treated bone marrow-derived macrophages (primary cells). In in vivo studies, CTPS significantly inhibited metastatic colonies and bodyweight loss as well as immunotoxicity in splenic T cells compared to the cisplatin-treated group in lung metastasis-induced mice. Furthermore, CTPS decreased the level of CRE and BUN in serum. In summation, these results suggest that CTPS-induced cytoprotective action may play a role in alleviating the side effects induced by chemotherapeutic drugs.


Assuntos
Cisplatino/toxicidade , Frutas/química , Macrófagos/efeitos dos fármacos , Melanoma Experimental/tratamento farmacológico , Moraceae/química , Extratos Vegetais/farmacologia , Polissacarídeos/farmacologia , Animais , Antineoplásicos/toxicidade , Apoptose , Proliferação de Células , Feminino , Humanos , Neoplasias Pulmonares/induzido quimicamente , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/secundário , Macrófagos/patologia , Melanoma Experimental/induzido quimicamente , Melanoma Experimental/patologia , Potencial da Membrana Mitocondrial , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Nus , Substâncias Protetoras/farmacologia , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
3.
Molecules ; 26(6)2021 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-33799689

RESUMO

Although our previous study revealed that gamma-irradiated chrysin enhanced anti-inflammatory activity compared to intact chrysin, it remains unclear whether the chrysin derivative, CM1, produced by gamma irradiation, negatively regulates toll-like receptor (TLR) signaling. In this study, we investigated the molecular basis for the downregulation of TLR4 signal transduction by CM1 in macrophages. We initially determined the appropriate concentration of CM1 and found no cellular toxicity below 2 µg/mL. Upon stimulation with lipopolysaccharide (LPS), CM1 modulated LPS-stimulated inflammatory action by suppressing the release of proinflammatory mediators (cytokines TNF-α and IL-6) and nitric oxide (NO) and downregulated the mitogen-activated protein kinase (MAPK) and nuclear factor-κB (NF-κB) signaling pathways. Furthermore, CM1 markedly elevated the expression of the TLR negative regulator toll-interacting protein (Tollip) in dose- and time-dependent manners. LPS-induced expression of cell surface molecules (CD80, CD86, and MHC class I/II), proinflammatory cytokines (TNF-α and IL-6), COX-2, and iNOS-mediated NO were inhibited by CM1; these effects were prevented by the knockdown of Tollip expression. Additionally, CM1 did not affect the downregulation of LPS-induced expression of MAPKs and NF-κB signaling in Tollip-downregulated cells. These findings provide insight into effective therapeutic intervention of inflammatory disease by increasing the understanding of the negative regulation of TLR signaling induced by CM1.


Assuntos
Flavonoides/farmacologia , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Macrófagos/metabolismo , Animais , Anti-Inflamatórios/farmacologia , Flavonoides/metabolismo , Flavonoides/efeitos da radiação , Inflamação/tratamento farmacológico , Interleucina-6 , Lipopolissacarídeos/efeitos adversos , Lipopolissacarídeos/farmacologia , Macrófagos/efeitos dos fármacos , Camundongos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , NF-kappa B/metabolismo , Óxido Nítrico , Células RAW 264.7 , Transdução de Sinais/efeitos dos fármacos , Receptor 4 Toll-Like/efeitos dos fármacos , Receptor 4 Toll-Like/metabolismo , Receptores Toll-Like/metabolismo , Fator de Necrose Tumoral alfa
4.
Br J Nutr ; 124(1): 23-33, 2020 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-32116206

RESUMO

The study investigated antioxidant effects of Se on resilience to diquat-induced oxidative stress in nursery pigs. Thirty-five weaned pigs were individually housed and randomly assigned to one of the five treatments. Pigs were (1) fed a basal diet and intraperitoneally injected with sterile saline (negative control), (2) fed the basal diet and injected with diquat solution (positive control, PC), or fed the basal diet supplemented with 0·3 mg Se/kg as (3) sodium selenite (SS), (4) soyabean protein-chelated Se (SC) or (5) selenised yeast (SY) and intraperitoneally injected with diquat. Pigs were fed the experimental diets for 17 d and injected with diquat at 10 mg/kg body weight or saline on the 11th day of the study (day 0 post-injection (PI)). Diquat exposure induced acute stress and innate immune activation (P < 0·05) at 6 h PI and compromised (P < 0·05) plasma glutathione peroxidase activity on day 2 PI, which was accompanied by an increase in plasma malondialdehyde at 6 h and day 2 PI (P < 0·10). Organic Se, particularly SY, enhanced (P < 0·05) endogenous antioxidant activity in various aspects compared with the PC group. The growth rate and feed intake from day 0 to day 7 PI were significantly lower in the PC, SS and SC groups than the NC group (P < 0·05). Untargeted metabolomics analysis revealed that twenty-two hepatic metabolites (false discovery rate < 0·15) associated with lipid and cellular antioxidant metabolism were altered by diquat. SY restored hepatic metabolic profiles in some but not all samples.

5.
Biosci Biotechnol Biochem ; 84(5): 1001-1012, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31960754

RESUMO

Crude extracts and phytochemical compounds derived from Annona muricata leaves have been demonstrated to exert neuroprotective effects. However, the neuroprotective effects of Annona muricata leaves-derived polysaccharide extracts (ALPs) have not been investigated. ALP treatment was shown to induce concentration-dependent antioxidant activity in HT22 cells, and to increase cell viability in H2O2-treated HT22 cells. These effects were correlated with a decrease in major components of oxidation, including: Ca2+, ROS, and malondialdehyde (MDA). Mediators of the intracellular response to oxidation, including Bax, cytochrome c, and cleaved caspases-3, -8, -9, MAPKs, and NF-κB, were positively influenced by ALP treatment under conditions of H2O2-mediated oxidative stress. In addition, ALP restored the expression of superoxide dismutase (SOD) and associated signaling pathways (PARP, PI3K/AKT and Nrf2-mediated HO-1/NQO-1) following H2O2 treatment. These results provide new pharmacological evidence that ALP facilitates neuroprotection via prevention of neuronal oxidative stress and promotion of cell survival signaling pathways.Abbreviations: ABTS: 2,2'-azino-bis-(3-ethylbenzothiazoline-6-sulfonicacid); AD: Alzheimer's disease; ALP: polysaccharide extracts isolated from Annona muricata leaves; ARE: antioxidant response element; DPPH: 1,1-diphenyl-picrylhydrazyl; DCFH-DA: 2',7'-dichlorofluorescin diacetate; ECL: electrochemiluminescence; ERK: extracellular regulated kinase; FBS: Fetal bovine serum; FITC: fluorescein isothiocyanate; FRAP: ferric reducing antioxidant power; HO-1: Heme oxygenase-1; JNK: c-jun N-terminal kinase; MAPKs: mitogen-activated protein kinases; MDA: malondialdehyde; MMP: mitochondrial membrane potential; MTT: 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazoliumbromide; NQO1: NAD(P)H:quinine oxidoreductase 1, Nrf2: nuclear factor-E2-related factor 2; PD: parkinson's disease; PI3K: phosphatidylinositol-3kinase; PVDF: polyvinylidene difluoride; ROS: reactive oxygen species; SOD: Superoxidedismutase; TPTZ: tripydyltriazine.


Assuntos
Annona/química , Antioxidantes/farmacologia , Peróxido de Hidrogênio/farmacologia , Neurônios/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Extratos Vegetais/farmacologia , Polissacarídeos/farmacologia , Animais , Apoptose/efeitos dos fármacos , Cálcio/metabolismo , Ciclo Celular/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Malondialdeído/análise , Malondialdeído/metabolismo , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/análise , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos , Superóxido Dismutase/análise , Superóxido Dismutase/metabolismo
6.
J Nutr ; 149(3): 398-405, 2019 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-30624730

RESUMO

BACKGROUND: Iron oversupplementation in healthy term infants may adversely affect growth and cognitive development. OBJECTIVE: We hypothesized that early-life iron excess causes systemic and central nervous system iron overload, and compromises social behavior. METHODS: The nursing pig was used as a translational model in a completely randomized study. On postnatal day (PD) 1, 24 pigs (1.57 ± 0.28 kg mean ± standard deviation body wt) were assigned to the following treatment groups: 1) nonsupplemented iron-deficient group (NON); 2) control group (CON), intramuscularly injected with iron dextran (100 mg Fe) on PD2; 3) moderate iron group (MOD), orally administered ferrous sulfate at 10 mg Fe · kg body wt-1 · d-1; and 4) high iron group (HIG), orally administered ferrous sulfate at 50 mg Fe · kg-1 · d-1. Piglets were nursed by sows during the study from PD1 to PD21. Tissue iron was analyzed by atomic absorption spectrophotometry. Messenger RNA and protein expression of iron regulator and transporters were analyzed by quantitative reverse transcriptase-polymerase chain reaction and Western blot. A sociability test was performed on PD19-20. RESULTS: Both MOD and HIG treatments (5.51 and 9.85 µmol/g tissue), but not CON (0.54 µmol/g), increased hepatic iron as compared with NON (0.25 µmol/g, P < 0.05). Similarly, the hippocampal iron concentrations in the MOD and HIG groups were 14.9% and 31.8% higher than that of NON, respectively (P < 0.05). In comparison with NON, MOD and HIG treatment repressed DMT1 in duodenal mucosa by 4- and 46-fold, respectively (P < 0.05); HIG drastically induced HAMP in liver by 540-fold (P < 0.05); iron-supplemented groups reduced TFRC in the hippocampus by <1-fold (P < 0.05). However, duodenal expression of ferroportin, the predominant transporter in basal membrane, was not affected by treatment. Despite normal sociability, the MOD and HIG pigs displayed deficits in social novelty recognition (P = 0.004). CONCLUSIONS: Duodenal ferroportin was hyporesponsive to iron excess (MOD and HIG), which caused hippocampal iron overload and impaired social novelty recognition in nursing pigs.


Assuntos
Animais Lactentes , Hipocampo , Sobrecarga de Ferro , Ferro da Dieta , Comportamento Social , Suínos , Animais , Feminino , Masculino , Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal , Dieta/veterinária , Suplementos Nutricionais/efeitos adversos , Relação Dose-Resposta a Droga , Hipocampo/efeitos dos fármacos , Sobrecarga de Ferro/induzido quimicamente , Sobrecarga de Ferro/veterinária , Ferro da Dieta/efeitos adversos , Peroxidação de Lipídeos , Distribuição Aleatória
7.
Water Sci Technol ; 80(3): 529-540, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31596264

RESUMO

A treatment and volume reduction process for a spent uranium-antimony catalyst has been developed. Targeted removal, immobilization and disposal of the uranium component has been confirmed, thus eliminating the radiological hazard. However, significant concentrations of antimony ([Sb] ≥ 25-50 mg L-1) remain in effluent from the process, which require removal in compliance with Korean wastewater regulations. Antimony(III/V) removal via co-precipitation with iron has been considered with optimal pH, dose and kinetics being determined. The effect of selected anions - Cl-, SO4 2- and PO4 3- - have also been considered, the latter present due to a prior uranium removal step. Removal of Sb(III) from both Cl- and SO4 2- media and Sb(V) removal from Cl- media to below release limits were found to be effective within 5 minutes at an iron dose of 8 mM (molar ratio, [FeIII]/[Sb] = 20) and a target pH of 5.0. However, Sb(V) removal from SO4 2- was significantly hampered requiring significantly higher iron dosages for the same removal performance. Phosphate poses significant challenges for the removal of Sb(V) due to competition between PO4 3- and Sb(OH)6 - species for surface binding sites, attributed to similarities in chemistries and a shared preference for an inner vs outer binding mechanism.


Assuntos
Acrilonitrila/química , Antimônio/análise , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/análise , Adsorção , Compostos Férricos , Águas Residuárias
8.
Apoptosis ; 21(4): 459-72, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26842846

RESUMO

Mycobacterium avium and its sonic extracts induce apoptosis in macrophages. However, little is known about the M. avium components regulating macrophage apoptosis. In this study, using multidimensional fractionation, we identified MAV2052 protein, which induced macrophage apoptosis in M. avium culture filtrates. The recombinant MAV2052 induced macrophage apoptosis in a caspase-dependent manner. The loss of mitochondrial transmembrane potential (ΔΨm), mitochondrial translocation of Bax, and release of cytochrome c from mitochondria were observed in macrophages treated with MAV2052. Further, reactive oxygen species (ROS) production was required for the apoptosis induced by MAV2052. In addition, ROS and mitogen-activated protein kinases were involved in MAV2052-mediated TNF-α and IL-6 production. ROS-mediated activation of apoptosis signal-regulating kinase 1 (ASK1)-JNK pathway was a major signaling pathway for MAV2052-induced apoptosis. Moreover, MAV2052 bound to Toll-like receptor (TLR) 4 molecule and MAV2052-induced ROS production, ΔΨm loss, and apoptosis were all significantly reduced in TLR4(-/-) macrophages. Altogether, our results suggest that MAV2052 induces apoptotic cell death through TLR4 dependent ROS production and JNK pathway in murine macrophages.


Assuntos
Apoptose/fisiologia , Proteínas de Bactérias/metabolismo , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Sistema de Sinalização das MAP Quinases/fisiologia , Macrófagos/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Receptor 4 Toll-Like/metabolismo , Animais , Linhagem Celular , Citocromos c/metabolismo , Feminino , Interleucina-6/metabolismo , MAP Quinase Quinase Quinase 5/metabolismo , Potencial da Membrana Mitocondrial , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Mycobacterium avium/metabolismo , Receptor 2 Toll-Like/genética , Receptor 4 Toll-Like/genética , Fator de Necrose Tumoral alfa/metabolismo , Proteína X Associada a bcl-2/metabolismo
9.
J Anim Sci Biotechnol ; 15(1): 1, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38169416

RESUMO

BACKGROUND: Our previous study has reported that supplementation of oligosaccharide-based polymer enhances gut health and disease resistance of pigs infected with enterotoxigenic E. coli (ETEC) F18 in a manner similar to carbadox. The objective of this study was to investigate the impacts of oligosaccharide-based polymer or antibiotic on the host metabolic profiles and colon microbiota of weaned pigs experimentally infected with ETEC F18. RESULTS: Multivariate analysis highlighted the differences in the metabolic profiles of serum and colon digesta which were predominantly found between pigs supplemented with oligosaccharide-based polymer and antibiotic. The relative abundance of metabolic markers of immune responses and nutrient metabolisms, such as amino acids and carbohydrates, were significantly differentiated between the oligosaccharide-based polymer and antibiotic groups (q < 0.2 and fold change > 2.0). In addition, pigs in antibiotic had a reduced (P < 0.05) relative abundance of Lachnospiraceae and Lactobacillaceae, whereas had greater (P < 0.05) Clostridiaceae and Streptococcaceae in the colon digesta on d 11 post-inoculation (PI) compared with d 5 PI. CONCLUSIONS: The impact of oligosaccharide-based polymer on the metabolic and microbial profiles of pigs is not fully understood, and further exploration is needed. However, current research suggest that various mechanisms are involved in the enhanced disease resistance and performance in ETEC-challenged pigs by supplementing this polymer.

10.
PLoS Pathog ; 7(12): e1002435, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22174691

RESUMO

Mycobacterium tuberculosis heparin-binding hemagglutinin (HBHA), a virulence factor involved in extrapulmonary dissemination and a strong diagnostic antigen against tuberculosis, is both surface-associated and secreted. The role of HBHA in macrophages during M. tuberculosis infection, however, is less well known. Here, we show that recombinant HBHA produced by Mycobacterium smegmatis effectively induces apoptosis in murine macrophages. DNA fragmentation, nuclear condensation, caspase activation, and poly (ADP-ribose) polymerase cleavage were observed in apoptotic macrophages treated with HBHA. Enhanced reactive oxygen species (ROS) production and Bax activation were essential for HBHA-induced apoptosis, as evidenced by a restoration of the viability of macrophages pretreated with N-acetylcysteine, a potent ROS scavenger, or transfected with Bax siRNA. HBHA is targeted to the mitochondrial compartment of HBHA-treated and M. tuberculosis-infected macrophages. Dissipation of the mitochondrial transmembrane potential (ΔΨ(m)) and depletion of cytochrome c also occurred in both macrophages and isolated mitochondria treated with HBHA. Disruption of HBHA gene led to the restoration of ΔΨ(m) impairment in infected macrophages, resulting in reduced apoptosis. Taken together, our data suggest that HBHA may act as a strong pathogenic factor to cause apoptosis of professional phagocytes infected with M. tuberculosis.


Assuntos
Proteínas de Bactérias/metabolismo , Macrófagos/metabolismo , Proteínas de Membrana/metabolismo , Mitocôndrias/metabolismo , Fatores de Virulência/metabolismo , Animais , Apoptose/efeitos dos fármacos , Apoptose/fisiologia , Proteínas de Bactérias/farmacologia , Caspases/metabolismo , Linhagem Celular , Separação Celular , Fragmentação do DNA , Ativação Enzimática/efeitos dos fármacos , Ativação Enzimática/fisiologia , Citometria de Fluxo , Humanos , Immunoblotting , Macrófagos/efeitos dos fármacos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Proteínas de Membrana/farmacologia , Camundongos , Microscopia de Fluorescência , Mitocôndrias/efeitos dos fármacos , Mycobacterium tuberculosis/metabolismo , Espécies Reativas de Oxigênio
11.
Microorganisms ; 11(2)2023 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-36838285

RESUMO

The objective of this study was to investigate supplementation of botanical blends (BB) comprised of 0.3% capsicum oleoresin and 12% garlic oil on gut microbiota and metabolomic profiles in serum and ileal mucosa of Escherichia coli infected pigs. Sixty weaned pigs were assigned to one of five treatments: negative control (CON-), positive control (CON+), dietary supplementation of 100 ppm BB1, 50 or 100 ppm BB2. All pigs, except CON-, were orally inoculated with 1010 CFU F18 ETEC/3-mL dose for 3 consecutive days after 7 d adaption. Feces, ileal digesta and cecal content were collected for 16S rRNA amplicon sequencing. Serum and ileal mucosa underwent primary metabolomics analysis. Supplementing 100 ppm BB1 increased (p < 0.05) relative abundances of Enterobacteriaceae and Escherichia-Shigella in ileum, and the relative abundances of Bacteroidota and Prevotellaceae in cecum than CON+ on d 5 post-inoculation (PI). Supplementing 100 ppm BB2 upregulated serum pinitol on d 4 PI and serum cholesterol and aminomalonic acids on d 21 PI, while supplementing 50 ppm BB2 reduced asparagine in ileal mucosa on d 5 PI than CON+. Supplementation with botanical blends modulated ileal and cecal microbiota and serum metabolomics profiles in weaned pigs under Escherichia coli challenge.

12.
J Anim Sci ; 1012023 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38044688

RESUMO

Enterotoxigenic Escherichia coli (ETEC) causes post-weaning diarrhea in piglets, significantly impacting animal welfare and production efficiency. The two primary ETEC pathotypes associated with post-weaning diarrhea are ETEC F4 and ETEC F18. During the post-weaning period, piglets may be exposed to both ETEC F4 and ETEC F18. However, the effects of coinfection by both strains have not been studied. Short chain fatty acid feed additives, such as butyrate and valerate, are being investigated for their potential to improve animal performance and disease resistance. Therefore, this pilot experiment aimed to test the effects of butyrate glycerides or valerate glycerides on growth performance, diarrhea incidence, and immune responses of piglets under ETEC F4-ETEC F18 coinfection conditions. Twenty piglets were individually housed and assigned to one of the three dietary treatments immediately at weaning (21 to 24 d of age). The dietary treatments included control (basal diet formulation), control supplemented with 0.1% butyrate glycerides or 0.1% valerate glycerides. After a 7-d adaptation, all pigs were inoculated with ETEC F4 and ETEC F18 (0.5 × 109 CFU/1.5 mL dose for each strain) on three consecutive days. Pigs and feeders were weighed throughout the trial to measure growth performance. Fecal cultures were monitored for hemolytic coliforms, and blood samples were collected for whole blood and serum analysis. Pigs fed valerate glycerides tended (P = 0.095) to have higher final body weight compared with control. The overall severity of diarrhea was significantly (P < 0.05) lower in both treatment groups than control. Pigs fed valerate glycerides tended (P = 0.061) to have lower neutrophils and had significantly (P < 0.05) lower serum TNF-α on day 4 post-inoculation. This pilot experiment established an appropriate experimental dose for an ETEC F4-ETEC F18 coinfection disease model in weaned piglets. Results also suggest that butyrate glycerides and valerate glycerides alleviated diarrhea and regulated immune responses in piglets coinfected with ETEC F4 and ETEC F18.


Piglets suffer from post-weaning diarrhea associated with Enterotoxigenic Escherichia coli (ETEC) F4 and F18, two prevalent strains on swine farms globally. Short chain fatty acids (SCFAs), such as butyrate and valerate, are natural, organic compounds that could potentially promote intestinal health when used as dietary supplements. During the post-weaning period, piglets are vulnerable to simultaneous infection by ETEC F4 and F18. Therefore, this experiment aimed to develop an experimental disease model for coinfection with ETEC F4 and F18, employing a dose of 0.5 × 109 CFU/1.5 mL of each strain, administered over three consecutive days. In addition, the experiment evaluated treatment diets supplemented with 0.1% butyrate or valerate glycerides compared with the control diet. Results from this experiment revealed that the inoculation dose incited infection and diarrhea in piglets, implying its suitability for use in a disease challenge model. Moreover, the results indicated that the inclusion of butyrate and valerate glycerides to pig's diet reduced the severity of diarrhea. Furthermore, pigs fed SCFA glycerides exhibited lowered levels of inflammatory blood markers. In conclusion, the experimental dose induced diarrhea in piglets, and dietary supplementation of butyrate and valerate glycerides alleviated the severity of diarrhea while augmenting inflammatory status.


Assuntos
Coinfecção , Escherichia coli Enterotoxigênica , Infecções por Escherichia coli , Doenças dos Suínos , Suínos , Animais , Escherichia coli Enterotoxigênica/fisiologia , Infecções por Escherichia coli/tratamento farmacológico , Infecções por Escherichia coli/veterinária , Butiratos/farmacologia , Valeratos/farmacologia , Valeratos/uso terapêutico , Coinfecção/veterinária , Diarreia/veterinária , Dieta/veterinária , Imunidade , Doenças dos Suínos/tratamento farmacológico , Ração Animal/análise
13.
Infect Chemother ; 55(1): 99-104, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37021427

RESUMO

The immunogenicity of a heterologous vaccination regimen consisting of ChAdOx1 nCoV-19 (a chimpanzee adenovirus-vectored vaccine) followed by mRNA-1273 (a lipid-nanoparticle-encapsulated mRNA-based vaccine) against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), specifically the omicron variant (B.1.1.529), is poorly studied. The aim of this study was to evaluate the neutralizing antibody activity and immunogenicity of heterologous ChAdOx1 nCoV-19 and mRNA-1273 prime-boost vaccination against wild-type (BetaCoV/Korea/KCDC03/2020), alpha, beta, gamma, delta, and omicron variants of SARS-CoV-2 in Korea. A 50% neutralizing dilution (ND50) titer was determined in serum samples using the plaque reduction neutralization test. Antibody titer decreased significantly at 3 months compared with that at 2 weeks after the 2nd dose. On comparing the ND50 titers for the above-mentioned variants of concerns, it was observed that the ND50 titer for the omicron variant was the lowest. This study provides insights into cross-vaccination effects and can be useful for further vaccination strategies in Korea.

14.
Immune Netw ; 23(4): e33, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37670807

RESUMO

Vaccination against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been acknowledged as an effective mean of preventing infection and hospitalization. However, the emergence of highly transmissible SARS-CoV-2 variants of concern (VOCs) has led to substantial increase in infections among children and adolescents. Vaccine-induced immunity and longevity have not been well defined in this population. Therefore, we aimed to analyze humoral and cellular immune responses against ancestral and SARS-CoV-2 variants after two shots of the BNT162b2 vaccine in healthy adolescents. Although vaccination induced a robust increase of spike-specific binding Abs and neutralizing Abs against the ancestral and SARS-CoV-2 variants, the neutralizing activity against the Omicron variant was significantly low. On the contrary, vaccine-induced memory CD4+ T cells exhibited substantial responses against both ancestral and Omicron spike proteins. Notably, CD4+ T cell responses against both ancestral and Omicron strains were preserved at 3 months after two shots of the BNT162b2 vaccine without waning. Polyfunctionality of vaccine-induced memory T cells was also preserved in response to Omicron spike protein. The present findings characterize the protective immunity of vaccination for adolescents in the era of continuous emergence of variants/subvariants.

15.
Front Immunol ; 14: 1139980, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36936968

RESUMO

Introduction: The effect of tixagevimab/cilgavimab (Evusheld™; AstraZeneca, UK) should be evaluated in the context of concurrent outbreak situations. Methods: For serologic investigation of tixagevimab/cilgavimab during the BA.5 outbreak period, sera of immunocompromised (IC) hosts sampled before and one month after tixagevimab/cilgavimab administration and those of healthcare workers (HCWs) sampled one month after a 3rd shot of COVID-19 vaccines, five months after BA.1/BA.2 breakthrough infection (BI), and one month after BA.5 BI were investigated. Semi-quantitative anti-spike protein antibody (Sab) test and plaque reduction neutralizing test (PRNT) against BA.5 were performed. Results: A total of 19 IC hosts (five received tixagevimab/cilgavimab 300 mg and 14 received 600 mg) and 41 HCWs (21 experienced BA.1/BA.2 BI and 20 experienced BA.5 BI) were evaluated. Baseline characteristics did not differ significantly between IC hosts and HCWs except for age and hypertension. Sab significantly increased after tixagevimab/cilgavimab administration (median 130.2 BAU/mL before tixagevimab/cilgavimab, 5,665.8 BAU/mL after 300 mg, and 10,217 BAU/mL after 600 mg; both P < 0.001). Sab of one month after the 3rd shot (12,144.2 BAU/mL) or five months after BA.1/BA.2 BI (10,455.8 BAU/mL) were comparable with that of tixagevimab/cilgavimab 600 mg, while Sab of one month after BA.5 BI were significantly higher (22,216.0 BAU/mL; P < 0.001). BA.5 PRNT ND50 significantly increased after tixagevimab/cilgavimab administration (median ND50 29.6 before tixagevimab/cilgavimab, 170.8 after 300 mg, and 298.5 after 600 mg; both P < 0.001). The ND50 after tixagevimab/cilgavimab 600 mg was comparable to those of five months after BA.1 BI (ND50 200.9) while ND50 of one month after the 3rd shot was significantly lower (ND50 107.6; P = 0.019). The ND50 of one month after BA.5 BI (ND50 1,272.5) was highest among tested groups, but statistical difference was not noticed with tixagevimab/cilgavimab 600 mg. Conclusion: Tixagevimab/cilgavimab provided a comparable neutralizing activity against the BA.5 with a healthy adult population who were vaccinated with a 3rd shot and experienced BA.1/BA.2 BI.


Assuntos
Infecções Irruptivas , COVID-19 , Adulto , Humanos , Vacinas contra COVID-19
16.
Immunology ; 136(2): 231-40, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22385341

RESUMO

Mycobacterial proteins interact with host macrophages and modulate their functions and cytokine gene expression profile. The protein Rv0652 is abundant in culture filtrates of Mycobacterium tuberculosis K-strain, which belongs to the Beijing family, compared with levels in the H37Rv and CDC1551 strains. Rv0652 induces strong antibody responses in patients with active tuberculosis. We investigated pro-inflammatory cytokine production induced by Rv0652 in murine macrophages and the roles of signalling pathways. In RAW264.7 cells and bone marrow-derived macrophages, recombinant Rv0652 induced predominantly tumour necrosis factor (TNF) and monocyte chemoattractant protein (MCP)-1 production, which was dependent on mitogen-activated protein kinases and nuclear factor-κB. Specific signalling pathway inhibitors revealed that the extracellular signal-regulated kinase 1/2 (ERK1/2), p38 and phosphatidylinositol 3-kinase (PI3K) pathways were essential for Rv0652-induced TNF production, whereas the ERK1/2 and PI3K pathways, but not the p38 pathway, were critical for MCP-1 production in macrophages. Rv0652-stimulated TNF and MCP-1 secretion by macrophages occurred in a Toll-like receptor 4-dependent and MyD88-dependent manner. In addition, Rv0652 significantly up-regulated the expression of the mannose receptor, CD80, CD86 and MHC class II molecules. These results suggest that Rv0652 can induce a protective immunity against M. tuberculosis through the macrophage activation.


Assuntos
Proteínas de Bactérias/imunologia , Quimiocina CCL2/biossíntese , Macrófagos/metabolismo , Mycobacterium tuberculosis/imunologia , Receptor 4 Toll-Like/imunologia , Fator de Necrose Tumoral alfa/biossíntese , Animais , Antígeno B7-1/biossíntese , Antígeno B7-1/imunologia , Antígeno B7-2/biossíntese , Antígeno B7-2/imunologia , Linhagem Celular , Quimiocina CCL2/imunologia , Genes MHC da Classe II/imunologia , Lectinas Tipo C/biossíntese , Lectinas Tipo C/imunologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/imunologia , Ativação de Macrófagos/efeitos dos fármacos , Ativação de Macrófagos/imunologia , Macrófagos/imunologia , Macrófagos/microbiologia , Masculino , Receptor de Manose , Lectinas de Ligação a Manose/biossíntese , Lectinas de Ligação a Manose/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Fator 88 de Diferenciação Mieloide/antagonistas & inibidores , Fator 88 de Diferenciação Mieloide/imunologia , NF-kappa B/antagonistas & inibidores , NF-kappa B/imunologia , Receptores de Superfície Celular/biossíntese , Receptores de Superfície Celular/imunologia , Fator de Necrose Tumoral alfa/imunologia
17.
J Phys Chem A ; 116(49): 12024-31, 2012 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-23181400

RESUMO

In this work, the formation of uranium species and their stabilities in Na-U(VI)-CO(3)-OH-H(2)O(2) solutions at different pHs are studied by Raman spectroscopy. In this solution, the UO(2)(O(2))(CO(3))(2)(4-) species was formed together with three other uranium species of UO(2)(O(2))(2)(2-), UO(2)(CO(3))(3)(4-), and a speculated uranium species of the uranyl carbonate hydroxide complex, UO(2)(CO(3))(x)(OH)(y)(2-2x-y), which showed remarkable Raman peaks at approximately 769, 848, 811, and 727 cm(-1), respectively. The UO(2)(O(2))(CO(3))(2)(4-) species disappeared at pH conditions where bicarbonate dominated, and its Raman peak could be clearly observed in only a narrow pH range from approximately 9 to 12. When the pH of the solution increased further, the UO(2)(O(2))(CO(3))(2)(4-) species changed to UO(2)(CO(3))(3)(4-) and the UO(2)(CO(3))(x)(OH)(y)(2-2x-y) species. Moreover, the UO(2)(O(2))(CO(3))(2)(4-) species continuously decomposed into uranyl tricarbonate in the carbonate solution at an elevated temperature because of the instability of the peroxide ion, O(2)(2-), in alkaline conditions.

18.
J Anim Sci Biotechnol ; 13(1): 59, 2022 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-35527278

RESUMO

BACKGROUND: Our previous study has shown that supplementation of trace amounts of antibiotic exacerbated the detrimental effects of enterotoxigenic E. coli (ETEC) infection and delayed the recovery of pigs that may be associated with modified metabolites and metabolic pathways. Therefore, the objective of this study was to explore the impacts of trace levels of antibiotic (carbadox) on host metabolic profiles and colon microbiota of weaned pigs experimentally infected with ETEC F18. RESULTS: The multivariate analysis highlighted a distinct metabolomic profile of serum and colon digesta between trace amounts of antibiotic (TRA; 0.5 mg/kg carbadox) and label-recommended dose antibiotic (REC; 50 mg/kg carbadox) on d 5 post-inoculation (PI). The relative abundance of metabolomic markers of amino acids, carbohydrates, and purine metabolism were significantly differentiated between the TRA and REC groups (q < 0.2). In addition, pigs in REC group had the highest (P < 0.05) relative abundance of Lactobacillaceae and tended to have increased (P < 0.10) relative abundance of Lachnospiraceae in the colon digesta on d 5 PI. On d 11 PI, pigs in REC had greater (P < 0.05) relative abundance of Clostridiaceae compared with other groups, whereas had reduced (P < 0.05) relative abundance of Prevotellaceae than pigs in control group. CONCLUSIONS: Trace amounts of antibiotic resulted in differential metabolites and metabolic pathways that may be associated with its slow responses against ETEC F18 infection. The altered gut microbiota profiles by label-recommended dose antibiotic may contribute to the promotion of disease resistance in weaned pigs.

19.
Front Immunol ; 13: 885253, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35990617

RESUMO

Enterotoxigenic Escherichia coli (ETEC) infection induced post-weaning diarrhea is one of the leading causes of morbidity and mortality in newly weaned pigs and one of the significant drivers for antimicrobial use in swine production. ETEC attachment to the small intestine initiates ETEC colonization and infection. The secretion of enterotoxins further disrupts intestinal barrier function and induces intestinal inflammation in weaned pigs. ETEC infection can also aggravate the intestinal microbiota dysbiosis due to weaning stress and increase the susceptibility of weaned pigs to other enteric infectious diseases, which may result in diarrhea or sudden death. Therefore, the amount of antimicrobial drugs for medical treatment purposes in major food-producing animal species is still significant. The alternative practices that may help reduce the reliance on such antimicrobial drugs and address animal health requirements are needed. Nutritional intervention in order to enhance intestinal health and the overall performance of weaned pigs is one of the most powerful practices in the antibiotic-free production system. This review summarizes the utilization of several categories of feed additives or supplements, such as direct-fed microbials, prebiotics, phytochemicals, lysozyme, and micro minerals in newly weaned pigs. The current understanding of these candidates on intestinal health and disease resistance of pigs under ETEC infection are particularly discussed, which may inspire more research on the development of alternative practices to support food-producing animals.


Assuntos
Escherichia coli Enterotoxigênica , Infecções por Escherichia coli , Enteropatias , Doenças dos Suínos , Animais , Antibacterianos/farmacologia , Diarreia/veterinária , Resistência à Doença , Infecções por Escherichia coli/tratamento farmacológico , Infecções por Escherichia coli/veterinária , Enteropatias/veterinária , Suínos , Desmame
20.
J Anim Sci Biotechnol ; 13(1): 10, 2022 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-35016715

RESUMO

BACKGROUND: There is a great demand for antibiotic alternatives to maintain animal health and productivity. The objective of this experiment was to determine the efficacy of dietary supplementation of a blood group A6 type 1 antigen oligosaccharides-based polymer (Coligo) on growth performance, diarrhea severity, intestinal health, and systemic immunity of weaned pigs experimentally infected with an enterotoxigenic Escherichia coli (ETEC), when compared with antibiotics. RESULTS: Pigs in antibiotic carbadox or Coligo treatment groups had greater (P < 0.05) body weight on d 5 or d 11 post-inoculation (PI) than pigs in the control group, respectively. Supplementation of antibiotics or Coligo enhanced (P < 0.05) feed efficiency from d 0 to 5 PI and reduced (P < 0.05) frequency of diarrhea throughout the experiment, compared with pigs in the control group. Supplementation of antibiotics reduced (P < 0.05) fecal ß-hemolytic coliforms on d 2, 5, and 8 PI. Pigs in antibiotics or Coligo groups had reduced (P < 0.05) neutrophil counts and serum haptoglobin concentration compared to pigs in the control group on d 2 and 5 PI. Pigs in Coligo had reduced (P < 0.05) total coliforms in mesenteric lymph nodes on d 5 and 11 PI, whereas pigs in antibiotics or Coligo groups had reduced (P < 0.05) total coliforms in spleen on d 11 PI compared with pigs in the control group. On d 5 PI, pigs in the Coligo group had greater (P < 0.05) gene expression of ZO1 in jejunal mucosa, but less (P < 0.05) mRNA expression of IL1B, IL6, and TNF in ileal mucosa, in comparison with pigs in the control group. Supplementation of antibiotics enhanced (P < 0.05) the gene expression of OCLN in jejunal mucosa but decreased (P < 0.05) IL1B and IL6 gene expression in ileal mucosa, compared with the control. On d 11 PI, supplementation of antibiotics or Coligo up-regulated (P < 0.05) gene expression of CLDN1 in jejunal mucosa, but Coligo reduced (P < 0.05) IL6 gene expression in ileal mucosa compared to pigs in the control group. CONCLUSIONS: Supplementation of Coligo improved growth performance, alleviated diarrhea severity, and enhanced gut health in weaned pigs infected with ETEC F18 in a manner similar to in-feed antibiotics.

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