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1.
Appl Opt ; 62(19): 5306-5316, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37707236

RESUMO

This paper proposes a Panax notoginseng (P. notoginseng) quantitative analysis based on terahertz time-domain spectroscopy and two-dimensional correlation spectroscopy (2DCOS). By imposing temperature perturbation combined with 2DCOS, the one-dimensional absorbance spectra were transformed into 2DCOS synchronous spectra, which reflected the differences in characteristic information between different P. notoginseng contents more clearly. Then, the feature information of P. notoginseng contents was extracted from the 2DCOS synchronous spectra by a competitive adaptive reweighted sampling (CARS) method and was used to build a quantitative model combined with a support vector regression machine (SVR), called 2DCOS-CARS-SVR. We obtained a more accurate analysis result than the commonly used principal component analysis (PCA)-partial least squares regression (PLSR) and PCA-SVR. The prediction set correlation coefficient and root mean square error reached 0.9915% and 0.8160%, respectively.

2.
Opt Lett ; 43(1): 17-20, 2018 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-29328226

RESUMO

We experimentally demonstrated a tunable terahertz bandpass filter based on microelectromechanical systems (MEMS) reconfigurable metamaterials. The unit cell of the filter consists of two split-ring resonators (SRRs) and a movable bar. Initially, the movable bar situates at the center of the unit cell, and the filter has two passbands whose central frequencies locate at 0.65 and 0.96 THz. The intensity of the two passbands can be actively modulated by the movable bar, and a maximum modulation depth of 96% is achieved at 0.96 THz. The mechanism of tunability is investigated using the finite-integration time-domain method. The result shows that the image currents induced on the movable bar are opposite the resonance currents induced on the SRRs and, thus, weaken the oscillating intensity of the resonance currents. This scheme paves the way to dynamically control and switch the terahertz wave at some constant frequencies utilizing induced image currents.

3.
J Environ Qual ; 47(5): 1068-1078, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30272802

RESUMO

Untreated surface waters can be contaminated with a variety of bacteria, including , some of which can be pathogenic for both humans and animals. Therefore, such waters need to be treated before their use in dairy operations to mitigate risks to dairy cow health and milk safety. To understand the molecular ecology of , this study aimed to assess antimicrobial resistance (AMR) in recovered from untreated surface water sources of dairy farms. Untreated surface water samples ( = 240) from 15 dairy farms were collected and processed to isolate . A total of 234 isolates were obtained and further characterized for their serotypes and antimicrobial susceptibility. Of the 234 isolates, 71.4% were pan-susceptible, 23.5% were resistant to one or two antimicrobial classes, and 5.1% were resistant to three or more antimicrobial classes. Whole genome sequence analysis of 11 selected multidrug-resistant isolates revealed AMR genes including and that confer resistance to the critically important extended-spectrum cephalosporins, as well as a variety of plasmids (mainly of the replicon type) and class 1 integrons. Phylogenetic and comparative genome analysis revealed a genetic relationship between some of the sequenced and Shiga toxin-producing O157:H7 (STEC), which warrants further investigation. This study shows that untreated surface water sources contain antimicrobial-resistant which may serve as a reservoir of AMR that could be disseminated through horizontal gene transfer. This is another reason why effective water treatment before usage should be routinely done on dairy farm operations.


Assuntos
Anti-Infecciosos , Escherichia coli O157 , Animais , Bovinos , Fazendas , Feminino , Humanos , Testes de Sensibilidade Microbiana , Ontário , Filogenia
4.
Infect Immun ; 85(6)2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28373356

RESUMO

Clostridium perfringens encodes at least two different quorum sensing (QS) systems, the Agr-like and LuxS, and recent studies have highlighted their importance in the regulation of toxin production and virulence. The role of QS in the pathogenesis of necrotic enteritis (NE) in poultry and the regulation of NetB, the key toxin involved, has not yet been investigated. We have generated isogenic agrB-null and complemented strains from parent strain CP1 and demonstrated that the virulence of the agrB-null mutant was strongly attenuated in a chicken NE model system and restored by complementation. The production of NetB, a key NE-associated toxin, was dramatically reduced in the agrB mutant at both the transcriptional and protein levels, though not in a luxS mutant. Transwell assays confirmed that the Agr-like QS system controls NetB production through a diffusible signal. Global gene expression analysis of the agrB mutant identified additional genes modulated by Agr-like QS, including operons related to phospholipid metabolism and adherence, which may also play a role in NE pathogenesis. This study provides the first evidence that the Agr-like QS system is critical for NE pathogenesis and identifies a number of Agr-regulated genes, most notably netB, that are potentially involved in mediating its effects. The Agr-like QS system thus may serve as a target for developing novel interventions to prevent NE in chickens.


Assuntos
Toxinas Bacterianas/metabolismo , Infecções por Clostridium/veterinária , Clostridium perfringens/patogenicidade , Enterite/veterinária , Enterotoxinas/metabolismo , Doenças das Aves Domésticas/microbiologia , Percepção de Quorum , Animais , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Toxinas Bacterianas/genética , Linhagem Celular Tumoral , Galinhas/microbiologia , Infecções por Clostridium/microbiologia , Infecções por Clostridium/patologia , Clostridium perfringens/genética , Clostridium perfringens/metabolismo , Enterite/microbiologia , Enterite/patologia , Enterotoxinas/genética , Regulação Bacteriana da Expressão Gênica , Masculino , Necrose , Óperon , Doenças das Aves Domésticas/patologia , Virulência , Fatores de Virulência/genética
5.
Artigo em Inglês | MEDLINE | ID: mdl-28533247

RESUMO

We previously described Salmonella enterica serovar Heidelberg isolates harboring a chromosomal gene cluster similar to the glutathione S-transferase gene, a putative fosA gene conferring resistance to fosfomycin. Here, we show that this new gene, named fosA7, confers resistance to fosfomycin. The introduction of fosA7 into the fosfomycin-susceptible Salmonella enterica serovar Enteritidis resulted in a substantial increase in the fosfomycin MIC. This finding increases the awareness of antibiotic resistance in Salmonella Heidelberg from broilers as related to the food safety and public health.


Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana/genética , Fosfomicina/farmacologia , Salmonella enterica/efeitos dos fármacos , Salmonella enterica/genética , Sequência de Aminoácidos , Animais , Galinhas , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão , Glutationa Transferase/genética , Doenças das Aves Domésticas/tratamento farmacológico , Doenças das Aves Domésticas/microbiologia , Salmonella enterica/isolamento & purificação
6.
Guang Pu Xue Yu Guang Pu Fen Xi ; 37(2): 618-23, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30292182

RESUMO

This paper develops an effective identification method to discriminate genetically modified (GM) and non-GM organisms. The method is proposed based on terahertz (THz) spectroscopy and support vector machines optimized by Cuckoo Search algorithm (CS-SVM). In this study, the THz spectra of three GM and non-GM soya seed samples were obtained by using terahertz time-domain spectroscopy (THz-TDS) system between 0.2 and 1.2 THz. Then, the SVM model is employed to distinguish GM and non-GM soya seeds, in which the two crucial parameters, including the penalty factor and kernel parameter, are optimized by CS algorithm. The experimental results show that THz spectroscopy combined with CS-SVM can provide a rapid, reliable and non-invasive method for GMOs and non-GMOs discrimination.

7.
Spectrochim Acta A Mol Biomol Spectrosc ; 287(Pt 1): 122046, 2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36334415

RESUMO

3-Hydroxybenzaldehyde (3-HBA) was investigated in the range of 0.6-2.8 THz by terahertz time-domain spectroscopy (THz-TDS) and solid-state density functional theory (ss-DFT) with first-principles calculation. Four distinct peaks were found respectively, and among them, the intensity disparity between experiment and simulation spectra at 2.04 THz was recognized as the biggest inconsistency. Considering thermal behavior can be responsible for this, quasi-harmonic approximation (QHA) method was introduced to mimic the unit cell volume expansion. According to vibrational modes analysis, it was ascertained that the biggest vibrational modes discrepancy was also located at 2.04 THz. Molecules in 0% and 4% unit cell expansion exhibit an opposite rotational direction in a-b plane compared with 2% unit cell expansion. Noncovalent intermolecular interactions were investigated with independent gradient model (IGM), and the result indicates that hydrogen bonding is the dominating noncovalent interaction of 3-HBA. While calculating systematic potential energy to the displaced bonds stretching involving hydrogen atoms, it was found the anomalous potential energy variation to the bond stretching provides a possible explanation for the rotation direction divergence, that is, the rotation direction divergence can be related to some hydrogen atoms seeking lower overall potential energy around their equilibrium positions during bond stretching in response to the variational intermolecular van der Waals force. This research combined THz-TDS with the quasi-harmonic approximation method, elucidating the principle of vibrational characteristics in different volumes, which is beneficial to the investigation of the terahertz low-frequency vibration to thermal behavior as a reference in biochemistry and other fields.

8.
Poult Sci ; 102(4): 102544, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36867921

RESUMO

This study evaluated effects of feeding low-bush wild blueberry (LBP) and organic American cranberry (CRP) pomaces without or with multienzyme supplement (ENZ) on growth performance, organ weight and plasma metabolites in broiler chickens. Nonenzyme-fed (no-ENZ: n = 1,575) and enzyme-fed (ENZ: n = 1,575) day-old male Cobb500 broilers were placed in floor pens (45 chicks/pen) and allocated to five corn-soybean meal-based diets: a basal diet supplemented with either bacitracin methylene disalicylate (BMD, 55 mg/kg), 0.5 or 1% of CRP or LBP in a 2 × 5 factorial design for 35-day experiment. Body weight (BW), feed intake (FI) and mortality were recorded whereas BW gain (BWG) and feed conversion ratio (FCR) were calculated. Birds were sampled at days 21 and 35 for organ weights and plasma metabolites. There were no interactions between diet and ENZ on any parameter (P > 0.05) and no effect of ENZ on overall (d 0-35) growth performance and organ weights (P > 0.05). Birds fed BMD were heavier (P < 0.05) at d 35 and had better overall FCR than berry-supplemented birds. Birds fed 1% LBP had poor FCR than birds fed 0.5% CRP. Birds fed LBP exhibited heavier liver (P < 0.05) than birds fed BMD or 1% CRP. The highest plasma concentrations of aspartate transaminase (AST), creatine kinase (CK) at d 28 and gamma-glutamyl transferase (GGT) at d 35 were found in ENZ-fed birds (P < 0.05). At d 28, birds fed 0.5% LBP showed higher plasma AST and CK concentrations (P < 0.05). However, CRP feeding resulted in a lower plasma CK level compared with BMD feeding (P < 0.05). The lowest cholesterol level was detected in 1% CRP-fed birds. In conclusion, this study showed no ENZ effects to potentiate berry pomaces on the overall growth performance of broilers (P < 0.05. However, plasma profiles revealed the potential of ENZ to modulate the metabolism of pomace-fed broilers. LBP increased BW during the starter phase, while CRP increased BW during the grower phase.


Assuntos
Galinhas , Zea mays , Animais , Masculino , Frutas , Tamanho do Órgão , Glycine max , Farinha , Suplementos Nutricionais/análise , Dieta/veterinária , Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal
9.
Microorganisms ; 11(5)2023 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-37317158

RESUMO

American cranberry (Vaccinium macrocarpon) and lowbush/wild blueberry (V. angustifolium) pomace are polyphenol-rich products having potentially beneficial effects in broiler chickens. This study investigated the cecal microbiome of broiler-vaccinated or non-vaccinated birds against coccidiosis. Birds in each of the two groups (vaccinated or non-vaccinated) were fed a basal non-supplemented diet (NC), a basal diet supplemented with bacitracin (BAC), American cranberry (CP), and lowbush blueberry (BP) pomace alone or in combination (CP + BP). At 21 days of age, cecal DNA samples were extracted and analyzed using both whole-metagenome shotgun sequencing and targeted-resistome sequencing approaches. Ceca from vaccinated birds showed a lower abundance of Lactobacillus and a higher abundance of Escherichia coli than non-vaccinated birds (p < 0.05). The highest and lowest abundance of L. crispatus and E. coli, respectively, were observed in birds fed CP, BP, and CP + BP compared to those from NC or BAC treatments (p < 0.05). Coccidiosis vaccination affected the abundance of virulence genes (VGs) related to adherence, flagella, iron utilization, and secretion system. Toxin-related genes were observed in vaccinated birds (p < 0.05) in general, with less prevalence in birds fed CP, BP, and CP + BP than NC and BAC (p < 0.05). More than 75 antimicrobial resistance genes (ARGs) detected by the shotgun metagenomics sequencing were impacted by vaccination. Ceca from birds fed CP, BP, and CP + BP showed the lowest (p < 0.05) abundances of ARGs related to multi-drug efflux pumps, modifying/hydrolyzing enzyme and target-mediated mutation, when compared to ceca from birds fed BAC. Targeted metagenomics showed that resistome from BP treatment was distant to other groups for antimicrobials, such as aminoglycosides (p < 0.05). Significant differences in the richness were observed between the vaccinated and non-vaccinated groups for aminoglycosides, ß-lactams, lincosamides, and trimethoprim resistance genes (p < 0.05). Overall, this study demonstrated that dietary berry pomaces and coccidiosis vaccination significantly impacted cecal microbiota, virulome, resistome, and metabolic pathways in broiler chickens.

10.
J Food Prot ; 86(1): 100008, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36916583

RESUMO

Healthy poultry can be a reservoir for extraintestinal pathogenic Escherichia coli (ExPEC), some of which could be multidrug resistant to antimicrobials. These ExPEC strains could contaminate the environment and/or food chain representing thus, food safety and human health risk. However, few studies have shown the virulence of poultry-source antimicrobial-resistant (AMR) ExPEC in humans. This study characterized AMR ExPEC and investigated the virulence potential of some of their isolates in a Caenorhabditis elegans infection model. A total of 46 E. coli isolates from poultry (chicken, n = 29; turkey, n = 12) retail meats and chicken feces (n = 4), or humans (n = 1) were sequenced and identified as ExPEC. Except eight, all remaining 38 ExPEC isolates were resistant to at least one antibiotic and carried corresponding antimicrobial resistance genes (ARGs). About 27 of the 46 ExPEC isolates were multidrug-resistant (≥3 antibiotic classes). Seven ExPEC isolates from chicken or turkey meats were of serotype O25:H4 and sequence type (ST) 131 which clustered with an isolate from a human urinary tract infection (UTI) case having the same serotype and ST. The C. elegans challenge model using eight of studied ExPEC isolates harboring various ARGs and virulence genes (VGs) showed that regardless of their ARG or VG numbers in tested poultry meat and feces, ExPEC significantly reduced the life span of the nematode (P < 0.05) similarly to a human UTI isolate. This study indicated the pathogenic potential of AMR ExPEC from retail poultry meat or feces, but more studies are warranted to establish their virulence in poultry and human. Furthermore, relationships between specific resistance profiles and/or VGs in these E. coli isolates for their pathogenicity deserve investigations.


Assuntos
Infecções por Escherichia coli , Escherichia coli Extraintestinal Patogênica , Animais , Humanos , Escherichia coli , Virulência , Aves Domésticas , Caenorhabditis elegans , Antibacterianos/farmacologia , Carne , Galinhas , Fatores de Virulência/genética , Filogenia
11.
Microbiology (Reading) ; 158(Pt 4): 1084-1093, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22301912

RESUMO

Escherichia coli O157 : H7 cells that interact with intestinal epithelial cells in animals and humans do so after passage through the low pH of the stomach. This study compared adherence and its associated virulence gene expression in acid-treated (AT) and non-acid treated (NAT) E. coli O157 : H7 strain 86-24 in vitro and in ligated pig intestine. It was found that in vitro, AT O157 : H7 had significantly decreased adherence accompanied by decreased expression of stcE and toxB but not of the locus of enterocyte effacement (LEE) genes. Expression of gadE, genes involved in quorum sensing, and the global regulators cyaA, hfq, lrp, fis and himA was significantly increased; notably, ureD expression was increased 29-fold compared with NAT O157 : H7. AT O157 : H7 colonized the pig intestine as effectively as NAT O157 : H7 bacteria. Expression of 70 of 72 virulence genes from bacteria recovered from the intestine was similar between AT and NAT O157 : H7, except ureD, pagC and bax, whose level of expression was reduced in the AT bacteria. Genes involved in acid response, regulators gadE, cyaA and hfq, and toxin synthesis genes (stx2A and stx2B) were expressed at significantly reduced levels in the intestine by both AT and NAT strains. Expression in the intestine of the LEE and putative adhesion factors cahA, iha and lpf2 was at levels similar to those in vitro, while ehaA and ureD in NAT O157 : H7 were expressed significantly more highly in vivo than in vitro. These data indicate that AT and NAT O157 : H7 behave differently, and that expression of their virulence genes is regulated differently in vitro from in vivo.


Assuntos
Ácidos/farmacologia , Aderência Bacteriana , Escherichia coli O157/genética , Intestinos/microbiologia , Virulência , Animais , Linhagem Celular , Células Epiteliais/microbiologia , Escherichia coli O157/efeitos dos fármacos , Escherichia coli O157/patogenicidade , Feminino , Regulação Bacteriana da Expressão Gênica , Genes Bacterianos , Humanos , Suínos , Transcriptoma
12.
J Oncol ; 2022: 6304824, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35242188

RESUMO

Clear cell renal cell carcinoma (ccRCC) is the most common primary malignancy of renal cancer in adults. Ferroptosis is critically associated with the prognosis of ccRCC. However, knowledge of long noncoding RNA- (lncRNA-) related ferroptosis that affects the prognosis of ccRCC is still insufficient. Using the LASSO regression, we created a risk model based on differentially expressed ferroptosis-related lncRNAs (FRLRS) in ccRCC. The analysis of Kaplan-Meier for survival, area under the curve (AUC) for diagnosis, nomogram for predicting overall survival, and gene expression for immune checkpoints were performed based on the screened independent prognostic factors. Nine lncRNAs were found to be associated with ccRCC prognosis. Furthermore, the prognostic AUC of the FRLRS signature was 0.78, demonstrating its usefulness in predicting ccRCC prognosis. The lncRNA risk model outperformed the standard clinical variables in predicting ccRCC prognosis. Finally, The Cancer Genome Atlas revealed that T cell functions, such as cytolytic activity, human leukocyte antigen activity, inflammation regulation, and type II interferon response coordination, are significantly different between two different risk levels of ccRCC. Immune checkpoints were also expressed differently in programmed cell death 1 receptor, inducible T cell costimulator, cytotoxic T-lymphocyte antigen-4, and leukocyte-associated immunoglobulin-like receptor 1. The nine FRLRS signature models may affect the prognosis of ccRCC.

13.
Infect Immun ; 79(4): 1688-95, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21300771

RESUMO

Enterotoxigenic Escherichia coli (ETEC) strains with K88 fimbriae are often associated with the outbreaks of diarrhea in newborn and weaned piglets worldwide. In the present study, we observed that 108 CFU/ml of K88(+) ETEC strain JG280 caused more death of pig intestinal IPEC-J2 cells than did 109 CFU/ml, suggesting that ETEC-induced cell death was cell density dependent and that quorum sensing (QS) may play a role in pathogenesis. Subsequent investigations demonstrated a positive correlation between autoinducer 2 (AI-2) activity of JG280 and death of IPEC-J2 cells during the infection for up to 3 h. However, there was a negative correlation between AI-2 activity and expression of the JG280 enterotoxin genes estA and estB when IPEC-J2 cells were exposed to the pathogen at 108 CFU/ml. We therefore cloned the luxS gene (responsible for AI-2 production) from JG280 and overexpressed it in E. coli DH5α, because deletion of the luxS gene was retarded by the lack of suitable antibiotic selection markers and the resistance of this pathogen to a wide range of antibiotics. The addition of culture fluid from E. coli DH5α with the overexpressed luxS reduced cell death of IPEC-J2 cells by 108 CFU/ml JG280. The addition also reduced the estA expression by JG280. Nonpathogenic K88(+) strain JFF4, which lacks the enterotoxin genes, caused no death of IPEC-J2 cells, although it produced AI-2 activity comparable to that produced by JG280. These results suggest the involvement of AI-2-mediated quorum sensing in K88(+) ETEC pathogenesis, possibly through a negative regulation of STa production.


Assuntos
Escherichia coli Enterotoxigênica/metabolismo , Escherichia coli Enterotoxigênica/patogenicidade , Enterotoxinas/genética , Homosserina/análogos & derivados , Lactonas/metabolismo , Animais , Proteínas de Bactérias/genética , Liases de Carbono-Enxofre/genética , Escherichia coli Enterotoxigênica/genética , Enterotoxinas/metabolismo , Infecções por Escherichia coli/genética , Infecções por Escherichia coli/metabolismo , Expressão Gênica , Regulação Bacteriana da Expressão Gênica/genética , Homosserina/genética , Homosserina/metabolismo , Percepção de Quorum , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Suínos , Fatores de Virulência/genética , Fatores de Virulência/metabolismo
14.
Appl Opt ; 50(20): 3609-14, 2011 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-21743573

RESUMO

FM-to-AM conversion in the ninth beam of the Shen Guang II laser system with sinusoidal phase-modulated spectra is calculated and analyzed. The simulations show that the intensity modulation at 3ω is much more serious compared to the other wavebands and it is mostly induced by the frequency conversion system rather than the amplification chain. The compensation effects of FM-to-AM conversion in the frequency conversion system by angular dispersion grating and cascaded crystals are numerically simulated and compared. Compared to the cascaded crystals, the angular dispersion grating could maintain higher frequency conversion efficiency with wide spectral width and offer a higher dynamic range of compensation effectiveness versus fundamental laser intensity. Combined with a precompensation filter before the amplification chain, FM-to-AM conversion at 3ω could be eliminated.

15.
J Food Prot ; 84(8): 1385-1399, 2021 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-33770170

RESUMO

ABSTRACT: This study was conducted to investigate the effects of in-feed encapsulated cinnamaldehyde (CIN) and citral (CIT) alone or in combination on antimicrobial resistance (AMR) phenotypes and genotypes of Escherichia coli isolates recovered from feces of 6-, 16-, 23-, and 27-day-old broiler chickens. The five dietary treatments including the basal diet (negative control [NC]) and the basal diet supplemented with 55 ppm of bacitracin (BAC), 100 ppm of encapsulated CIN, 100 ppm of encapsulated CIT, or 100 ppm each of encapsulated CIN and encapsulated CIT (CIN+CIT). Antimicrobial susceptibility testing of 240 E. coli isolates revealed that the most common resistance was to ß-lactams, aminoglycosides, sulfonamides, and tetracycline; however, the prevalence of AMR decreased (P < 0.05) as birds aged. The prevalence of resistance to amoxicillin-clavulanic acid, ceftiofur, ceftriaxone, cefoxitin, gentamicin, and sulfonamide was lower (P < 0.05) in isolates from the CIN or CIN+CIT groups than in isolates from the NC or BAC groups. Whole genome sequencing of 227 of the 240 isolates revealed 26 AMR genes and 19 plasmids, but the prevalence of some AMR genes and the number of plasmids were lower (P < 0.05) in E. coli isolated from CIN or CIN+CIT birds than in isolates from NC or BAC birds. The most prevalent resistance genes were tet(A) (108 isolates), aac(3)-VIa (91 isolates), aadA1 (86 isolates), blaCMY-2 (78 isolates), sul1 (77 isolates), aph(3)-Ib (58 isolates), aph(6)-Id (58 isolates), and sul2 (24 isolates). The numbers of most virulence genes carried by isolates increased (P < 0.05) in chickens from 6 to 27 days of age. The prevalence of E. coli O21:H16 isolates was lower (P < 0.05) in CIN and CIN+CIT, and the colibacillosis-associated multilocus sequence type (ST117) was most prevalent in isolates from 23-day-old chickens. A phylogenetic tree of whole genome sequences revealed a close relationship between 25 of the 227 isolates and human or broiler extraintestinal pathogenic E. coli strains. These findings indicate that AMR and virulence genotypes of E. coli could be modulated by providing encapsulated CIN or CIN+CIT feed supplements, but further investigation is needed to determine the mechanisms of the effects of these supplements.


Assuntos
Infecções por Escherichia coli , Doenças das Aves Domésticas , Acroleína/análogos & derivados , Monoterpenos Acíclicos , Idoso , Animais , Antibacterianos/farmacologia , Galinhas , Farmacorresistência Bacteriana/genética , Escherichia coli/genética , Infecções por Escherichia coli/veterinária , Genótipo , Humanos , Fenótipo , Filogenia
16.
Poult Sci ; 100(2): 517-526, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33518104

RESUMO

With the pressure to reduce antibiotics use in poultry production, cost-effective alternative products need to be developed to enhance the bird's immunity. The present study evaluated the efficacy of cranberry fruit by-products to modulate immunity in broiler chickens. Broiler Cobb 500 chicks were fed a control basal diet, basal diet supplemented with bacitracin (BACI, 55 ppm), cranberry pomace at 1% and 2% (CP2), or cranberry pomace ethanolic extract at 150 and 300 ppm (COH300) for 30 d. Blood sera were analyzed at days 21 and 28 of age for Ig levels by ELISA. The innate and adaptive immune-related gene expression levels in the liver and bursa of Fabricius were investigated at 21 d of age by quantitative polymerase chain reaction arrays. At day 21, the highest IgY level was found in the blood serum of the CP2-fed birds. In the liver, 13 of the 22 differentially expressed genes were downregulated across all treatments compared with the control. Expression of genes belonging to innate immunity such as caspase 1 apoptosis-related cysteine peptidase, chemokine receptor 5, interferon gamma, myeloid differentiation primary response gene 88, and Toll-like receptor 3 were significantly downregulated mainly in BACI- and COH300-fed birds. In the bursa, 5 of 9 genes associated with the innate immunity were differentially expressed. The expression of anti-inflammatory IL-10 gene was upregulated in all treatment groups in bursa compared with the control. The expression of transferrin gene was significantly upregulated in livers of birds fed COH300 and in bursa of birds fed BACI, indicating feeding practices and organ-dependant modulation of this gene in broiler. Overall results of this study showed that cranberry product feed supplementation modulated the innate immune and suppressed proinflammatory cytokines in broilers, providing a platform for future investigations to develop berry products in poultry feeding.


Assuntos
Bolsa de Fabricius/imunologia , Galinhas/imunologia , Suplementos Nutricionais , Fígado/imunologia , Vaccinium macrocarpon , Imunidade Adaptativa/genética , Ração Animal/análise , Animais , Bolsa de Fabricius/efeitos dos fármacos , Galinhas/sangue , Dieta/veterinária , Suplementos Nutricionais/análise , Frutas , Imunidade Inata/genética , Imunoglobulinas/sangue , Fígado/efeitos dos fármacos , Extratos Vegetais/administração & dosagem , Extratos Vegetais/farmacologia , Vaccinium macrocarpon/química
17.
Front Immunol ; 12: 621803, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34149685

RESUMO

Feeding practices have been found to influence gut microbiota which play a major role in immunity of poultry. In the present study, changes in cecal microbiota and humoral responses resulting in the 55 ppm bacitracin (BACI), 1% each of cranberry (CP1) and wild blueberry (BP1) pomace alone or in combination (CP+BP) feeding in broiler Cobb 500 vaccinated or not against coccidiosis were investigated. In the non-vaccinated group, no significant treatment effects were observed on performance parameters. Vaccination significantly affected bird's performance parameters particularly during the growing phase from 10 to 20 days of age. In general, the prevalence of coccidiosis and necrotic enteritis (NE) was reduced by vaccination (P < 0.05). BACI-treated birds showed low intestinal lesion scores, and both CP1 and BP1 feed supplementations reduced Eimeria acervulina and Clostridium perfringens incidences similar to BACI. Vaccination induced change in serum enzymes, minerals, and lipid levels in 21-day old birds while, levels of triglyceride (TRIG) and non-esterified fatty acids (NEFA) were higher (P < 0.05) in CP1 treated non-vaccinated group than in the control. The levels of NEFA were lower in BACI- and CP1-fed birds than in the control in non-vaccinated day 28 old birds. The highest levels of all estimated three immunoglobulins (IgY, IgM, and IgA) were found in the vaccinated birds. Metagenomics analysis of the cecal bacterial community in 21-day old birds showed the presence of Firmicutes (90%), Proteobacteria (5%), Actinobacteria (2%), and Bacteroidetes (2%). In the vaccinated group, an effect of BACI was noted on Proteobacteria (P = 0.03). Vaccination and/or dietary treatments influenced the population of Lactobacillaceae, Enterobacteriaceae, Clostridiaceae, and Streptococcaceae which were among the most abundant families. Overall, this study revealed that besides their beneficial effects on performance, alike bacitracin, berry pomaces in poultry feed have profound impacts on the chicken cecal microbiota and blood metabolites that could be influenced by vaccination against coccidiosis.


Assuntos
Infecções Bacterianas/imunologia , Doenças das Aves/imunologia , Ceco/microbiologia , Galinhas/imunologia , Coccídios/fisiologia , Coccidiose/imunologia , Eimeria/fisiologia , Microbioma Gastrointestinal/imunologia , Vacinas Protozoárias/imunologia , Ração Animal , Fenômenos Fisiológicos da Nutrição Animal , Animais , Bacitracina , Mirtilos Azuis (Planta) , Imunidade Humoral , Metabolismo dos Lipídeos , Vacinação , Vaccinium macrocarpon
18.
Appl Environ Microbiol ; 76(13): 4461-8, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20453145

RESUMO

Verotoxin (VT) has been implicated in the promotion of adherence to and colonization of intestinal epithelial cells by enterohemorrhagic Escherichia coli (EHEC) O157:H7. The present study investigated the effect of VT2 on the adherence of EHEC O157:H7 strain 86-24 to porcine jejunal (IPEC-J2), human colon (CaCo-2), and human laryngeal carcinoma (HEp-2) cell lines and on the expression in IPEC-J2 cells of synthases for beta1-integrin and nucleolin, both of which are implicated in bacterial adherence. The effect on expression of globotriaosylceramide (Gb3) synthase, the receptor for VT, was also examined. Data were obtained by adherence assays and quantitative reverse transcriptase PCR, using EHEC O157 strain 86-24, a vt2 deletion mutant, a vt2 phage-negative strain, and complemented mutants in which the vt2 gene was restored. Compared with the adherence of the parent and complemented mutant strains, the vt2-negative strains adhered significantly less to all three types of cells. Adherence of the wild-type EHEC strain to IPEC-J2 cells was accompanied by increased expression of beta1-integrin, nucleolin, and Gb3 synthase. IPEC-J2 cells in association with wild-type EHEC O157:H7 or the complemented mutants expressed higher levels of beta1-integrin than did cells in association with the vt2-negative strains or with no bacteria. Expression of nucleolin was decreased by association with the vt2-negative mutant, but complementation failed to restore wild-type expression. The data indicate that VT2 plays a role in the adherence of EHEC O157:H7 to intestinal epithelial cells, possibly by increasing the expression of the host receptor beta1-integrin.


Assuntos
Aderência Bacteriana/efeitos dos fármacos , Células Epiteliais/microbiologia , Escherichia coli O157/fisiologia , Jejuno/microbiologia , Toxina Shiga II/metabolismo , Animais , Linhagem Celular , Linhagem Celular Tumoral , Colo/citologia , Colo/microbiologia , Células Epiteliais/citologia , Escherichia coli O157/metabolismo , Galactosiltransferases/metabolismo , Humanos , Integrina beta1/metabolismo , Jejuno/citologia , Fosfoproteínas/metabolismo , Proteínas de Ligação a RNA/metabolismo , Toxina Shiga II/farmacologia , Suínos , Nucleolina
19.
Zhong Yao Cai ; 33(1): 55-7, 2010 Jan.
Artigo em Zh | MEDLINE | ID: mdl-20518305

RESUMO

OBJECTIVE: To study the chemical constituents of Humulus scandens. METHODS: The compounds were isolated by column chromatography on silica gel and Sephadex LH-20. The structures were identified by means of IR, 1H-NMR,13C-NMR and MS analyses. RESULTS: Seven compounds were isolated and identified as friedelanone (I), cis-asarone (II), epifriedelanol (III), stigmasta-4-ene-3,6-dione (IV), gamma-sitosterol (V), n-hexadecanoic acid (VI), and linoleic acid (VII), respectively. CONCLUSION: All compounds are isolated from this species for the first time and compounds I - V are obtained from this genus for the first time.


Assuntos
Colestenonas/isolamento & purificação , Humulus/química , Plantas Medicinais/química , Sitosteroides/isolamento & purificação , Triterpenos/isolamento & purificação , Colestenonas/química , Cromatografia Gasosa-Espectrometria de Massas/métodos , Ácido Linoleico/química , Ácido Linoleico/isolamento & purificação , Estrutura Molecular , Ácido Palmítico/química , Ácido Palmítico/isolamento & purificação , Sitosteroides/química , Triterpenos/química
20.
Poult Sci ; 99(2): 936-948, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32029170

RESUMO

This study investigated the effects of encapsulated cinnamaldehyde (CIN) and citral (CIT) alone or in combination (CIN + CIT) on the growth performance and cecal microbiota of nonvaccinated broilers and broilers vaccinated against coccidiosis. Vaccinated (1,600) and nonvaccinated (1,600) 0-day-old male Cobb500 broilers were randomly allocated to 5 treatments: basal diet (control) and basal diet supplemented with bacitracin (BAC, 55 ppm), CIN (100 ppm), CIT (100 ppm), and CIN (100 ppm) + CIT (100 ppm). In general, body weight (BW) and feed conversion ratio were significantly improved in birds treated with BAC, CIN, CIT, and CIN + CIT (P < 0.05) but were all decreased in vaccinated birds compared with nonvaccinated birds (P < 0.05). Significant interactions (P < 0.05) between vaccination and treatments for average daily gain during the periods of starter (day 0-9) and BW on day 10 were noted. Broilers receiving vaccines (P < 0.01) or feed supplemented with BAC, CIN, CIT, or CIN + CIT (P < 0.01) showed reductions in mortality rate from day 0 to 28. The incidences of minor coccidiosis were higher (P < 0.05) in vaccinated birds than in nonvaccinated birds. Diet supplementation with BAC or tested encapsulated essential oils showed comparable effects on the coccidiosis incidences. Similar to BAC, CIN and its combination with CIT reduced both incidence and severity of necrotic enteritis (P < 0.05). No treatment effects were observed on the cecal microbiota at the phyla level. At the genus level, significant differences between vaccination and treatment groups were observed for 5 (Lactobacillus, Ruminococcus, Faecalibacterium, Enterococcus, and Clostridium) of 40 detected genera (P < 0.05). The genus Lactobacillus was more abundant in broilers fed with CIT, while Clostridium and Enterococcus were less abundant in broilers fed with CIN, CIT, or CIN + CIT in both the vaccinated and nonvaccinated groups. Results from this study suggested that CIN alone or in combination with CIT in feed could improve chicken growth performance to the level comparable with BAC and alter cecal microbiota composition.


Assuntos
Acroleína/análogos & derivados , Monoterpenos Acíclicos/metabolismo , Galinhas/fisiologia , Microbioma Gastrointestinal/efeitos dos fármacos , Interações entre Hospedeiro e Microrganismos/efeitos dos fármacos , Vacinas Protozoárias/administração & dosagem , Acroleína/administração & dosagem , Acroleína/metabolismo , Monoterpenos Acíclicos/administração & dosagem , Ração Animal/análise , Animais , Ceco/microbiologia , Galinhas/crescimento & desenvolvimento , Galinhas/microbiologia , Coccidiose/parasitologia , Coccidiose/terapia , Coccidiose/veterinária , Dieta/veterinária , Suplementos Nutricionais/análise , Relação Dose-Resposta a Droga , Masculino , Doenças das Aves Domésticas/parasitologia , Doenças das Aves Domésticas/terapia , Distribuição Aleatória , Vacinação/veterinária
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