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Apple Valsa canker (AVC) weakens apple trees and significantly reduces apple production in China and other East Asian countries. Thus far, very few AVC-targeting biocontrol resources have been described. Here, we present a thorough description of a fungal isolate (Chaetomium globosum, 61239) that has strong antagonistic action toward the AVC causal agent Cytospora mali. Potato dextrose broth culture filtrate of strain 61239 completely suppressed the mycelial growth of C. mali on potato dextrose agar, and strongly constrained the development of AVC lesions in in vitro infection assays. ultra-performance liquid chromatography (UPLC) and HPLC-MS/MS investigations supported the conclusion that strain 61239 produces chaetoglobosin A, an antimicrobial metabolite that inhibits C. mali. Using genome sequencing, we discovered a gene cluster in strain 61239 that may be responsible for chaetoglobosin A production. Two of the cluster's genes-cheA, a PKS-NRPS hybrid enzyme, and cheB, an enoyl reductase-were individually silenced, which significantly decreased chaetoglobosin A accumulation as well as the strain's antagonistic activity against C. mali. Together, the findings of our investigation illustrate the potential use of Chaetomium globosum for the management of AVC disease and emphasize the significant contribution of chaetoglobosin A to the antagonistic action of strain 61239.
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Colletotrichum fungi are a group of damaging phytopathogens with atypical mating type loci (harboring only MAT1-2-1 but not MAT1-1-1) and complex sexual behaviors. Sex pheromones and their cognate G-protein-coupled receptors are conserved regulators of fungal mating. These genes, however, lose function frequently among Colletotrichum species, indicating a possibility that pheromone signaling is dispensable for Colletotrichum sexual reproduction. We have identified two putative pheromone-receptor pairs (PPG1:PRE2, PPG2:PRE1) in C. fructicola, a species that exhibits plus-to-minus mating type switching and plus-minus-mediated mating line development. Here, we report the generation and characterization of gene-deletion mutants for all four genes in both plus and minus strain backgrounds. Single-gene deletion of pre1 or pre2 had no effect on sexual development, whereas their double deletion caused self-sterility in both the plus and minus strains. Moreover, double deletion of pre1 and pre2 caused female sterility in plus-minus outcrossing. Double deletion of pre1 and pre2, however, did not inhibit perithecial differentiation or plus-minus-mediated enhancement of perithecial differentiation. Contrary to the results with pre1 and pre2, double deletion of ppg1 and ppg2 had no effect on sexual compatibility, development, or fecundity. We concluded that pre1 and pre2 coordinately regulate C. fructicola mating by recognizing novel signal molecule(s) distinct from canonical Ascomycota pheromones. The contrasting importance between pheromone receptors and their cognate pheromones highlights the complicated nature of sex regulation in Colletotrichum fungi.
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Colletotrichum , Receptores de Feromonas , Receptores de Feromonas/genética , Feromonas/genética , Colletotrichum/genética , Enfermedades de las Plantas , Reproducción , Fertilidad , Genes del Tipo Sexual de los Hongos/genética , Proteínas Fúngicas/genéticaRESUMEN
The composition of the microbiome in the early stages of life can directly affect the health of developing infants, and prior evidence suggests that human milk oligosaccharides (HMO) are critical regulators in the maintenance of a healthy gut microbiota in infants. Herein, we conducted an analysis of the gut microbiota of 1-mo-old breastfed infants from Jining and Harbin, China, and a corresponding analysis of the HMO profiles in samples of maternal breast milk. Quantification of HMO was conducted via liquid chromatography-mass spectrometry, and bacterial DNA sequencing was employed for characterization of the fecal microbiota. The abundances of total neutral oligosaccharides, lactodifucotetraose, lacto-N-fucopentaose I, and disialyl-lacto-N-tetraose were significantly increased in samples from the Jining group relative to the Harbin group. Bifidobacterium were the predominant microbial species in infants from both Harbin and Jining, with these levels being significantly higher in the former set. Correlation analyses evaluating microbes and 19 different HMO indicated that HMO were beneficial to the development of the gut microbiota in young infants. The predominance of Bifidobacterium in these microbial communities suggests that their ability to efficiently utilize HMO can contribute to the homeostasis of the gut microflora, with breast milk-derived HMO being critical to the shaping of the gut microbiota in breastfed infants.
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Microbioma Gastrointestinal , Leche Humana , Animales , Bifidobacterium , Lactancia Materna , Femenino , Microbioma Gastrointestinal/genética , Humanos , Leche Humana/química , Oligosacáridos/análisisRESUMEN
Sea surface emissivity (SSE) is a key variable in the estimation of sea surface temperature and the sea surface radiation budget. A physical base SSE model with adequate accuracy and acceptable computational efficiency is highly desired. This paper develops a Monte Carlo ray-tracing model to compute the SSE of a wind-roughened sea surface. The adoption of a two-dimensional continuous surface model and averaging the two polarization components in advance before ray-tracing gives the model acceptable computational efficiency. The developed model can output the contributions of direct emission and the reflected component to the effective emissivity. The contribution of the reflected component to the effective emissivity reaches 0.035 at an 80° emission angle for a wind speed larger than 10 m/s. The emissivity spectra and channel emissivities collected from two field campaigns and one set of outdoor measurements are used to validate the developed model. Statistical results indicate that the absolute value of bias or difference is less than 0.5% when the view angle is less than 65°, which means the retrieval accuracy of sea surface temperature (SST) is guaranteed from the view of SSE. When the view angle increases, the accuracy of the developed model degraded, especially at the view angle of 85°. Without considering this view angle, the absolute value of bias or difference is less than 0.016, and the root mean square difference (RMSD) is less than 0.018.
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This study aims to investigate the correlation between the ability of L. acidophilus to modulate miRNA expression and prevent Th17-dominated ß-lactoglobulin (ß-Lg) allergy. In vitro immunomodulation was evaluated by measuring splenocyte proliferation, Th17-related immune response and miRNA expression in ß-Lg-sensitized splenocytes cultured with live L. acidophilus. Next, the allergic mouse model was used to evaluate anti-allergy capability of lactobacilli. The ß-Lg challenge led to induction of up-regulation of miR-146a, miR-155, miR-21 and miR-9 expression in both in vivo and in vitro, along with increased Th17-related cytokine levels and mRNA expression of RORγt and IL-17. However, treatment of live L. acidophilus significantly suppressed hypersensitivity responses and Th17 cell differentiation. Moreover, administration of live L. acidophilus reduced expression of four miRNAs, especially miR-146a and miR-155. In addition, the decreased expression of the miRNAs in the spleen of the L. acidophilus-treated group was closely associated with decrease of IL-17 and RORγt mRNA expression.
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Lactobacillus acidophilus , Lactoglobulinas/efectos adversos , MicroARNs/genética , Hipersensibilidad a la Leche/etiología , Hipersensibilidad a la Leche/prevención & control , Animales , Bovinos , Polaridad Celular , Citocinas/metabolismo , Modelos Animales de Enfermedad , Regulación hacia Abajo , Femenino , Técnicas In Vitro , Lactoglobulinas/administración & dosificación , Ratones Endogámicos BALB C , Hipersensibilidad a la Leche/genética , Hipersensibilidad a la Leche/inmunología , Reacción en Cadena en Tiempo Real de la Polimerasa , Células Th17/citología , Células Th17/inmunologíaRESUMEN
Lactobacillus plantarum KLDS1.0391 is a probiotic strain isolated from the traditional fermented dairy products and identified to produce bacteriocin against Gram-positive and Gram-negative bacteria. Previous studies showed that the strain has a high resistance to gastrointestinal stress and has a high adhesion ability to the intestinal epithelial cells (Caco-2). We reported the entire genome sequence of this strain, which contains a circular 2,886,607-bp chromosome and three circular plasmids. Genes, which are related to the biosynthesis of bacteriocins, the stress resistance to gastrointestinal tract environment and adhesive performance, were identified. Whole genome sequence of Lactobacillus plantarum KLDS1.0391 will be helpful for its applications in food industry.
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Bacteriocinas/biosíntesis , Genoma Bacteriano , Lactobacillus plantarum/fisiología , Análisis de Secuencia de ADN/métodos , Adhesión Bacteriana , Proteínas Bacterianas/genética , Bacteriocinas/genética , Células CACO-2 , Tracto Gastrointestinal/microbiología , Tamaño del Genoma , Humanos , Lactobacillus plantarum/genética , Familia de Multigenes , Probióticos , Estrés FisiológicoRESUMEN
Objective To investigate the clinical features of patients with inflammatory bowel disease (IBD) complicated with Pneumocystis Jiroveci Pneumonia (PJP). Methods We retrospectively analyzed the clinical data of 5 patients who were hospitalized in Peking Union Medical College Hospital from January 2012 to July 2017 for treatment of IBD complicated with PJP. Demographic characteristics,clinical manifestations,treatments,and outcomes were descriptively analyzed. Results Of these five patients,four had ulcerative colitis (UC) and one had Crohn's disease (CD). All patients were males,with an average age of (61.8±1.9) years. All patients were in active disease status and had symptoms including cough and suffocation. Three patients had hypoxemia,among whom two developed type 1 respiratory failure. Three patients were treated with immunosuppressive medications (corticosteroids and/or immunosuppressant drugs) before the diagnosis of PJP. Lymphocyte counts in three patients were less than 0.6×109/L. CD4+T cells in two patients were less than 200×106/L. Four patients had elevated serum cytomegalovirus DNA. The level of ß-D-glucan was elevated in four patients. Chest CT showed bilateral diffuse ground glass opacification. PJP-DNA was positive in sputum or bronchoalveolar lavage fluid in all patients. Two patients with type 1 respiratory failure required invasive mechanical ventilation. All patients received trimethoprim-sulfamethoxazole and methylprednisolone treatment. Four patients recovered completely and one died. Conclusion Elderly (aged>55 years) IBD patients who are receiving immune-suppressive therapy or with decreased peripheral blood lymphocyte count are at higher risk of PJP.
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Enfermedades Inflamatorias del Intestino/microbiología , Pneumocystis carinii , Neumonía por Pneumocystis/complicaciones , Colitis Ulcerosa/complicaciones , Colitis Ulcerosa/microbiología , Enfermedad de Crohn/complicaciones , Enfermedad de Crohn/microbiología , Humanos , Enfermedades Inflamatorias del Intestino/complicaciones , Masculino , Persona de Mediana Edad , Neumonía por Pneumocystis/fisiopatología , Estudios RetrospectivosRESUMEN
PURPOSE: To evaluate safety and efficacy of balloon dilation and stent placement combined with thrombus aspiration and thrombolysis to treat patients with Budd-Chiari syndrome (BCS) with inferior vena cava (IVC) thrombosis. MATERIALS AND METHODS: Charts from 55 consecutive patients with primary BCS and IVC thrombosis treated between April 2000 and August 2014 were retrospectively analyzed. Transcatheter aspiration and percutaneous recanalization were attempted in all patients, and stents were placed if balloon dilation was successful. Catheter-directed thrombolysis was performed when evident clot burden was present after recanalization. RESULTS: Technically successful IVC recanalization was achieved in 53 of 55 patients (96.4%). Technical failures in 2 patients were due to long segment of IVC obstruction. A stent was placed in 47 of 53 patients (88.7%). Thrombus was successfully aspirated in 23 patients, and thrombolytic treatment was administered to 13 patients. Median follow-up was 58 months (range, 8-180 mo). No symptomatic pulmonary embolism occurred. Reocclusion occurred in 8 patients, and 6 of these patients (75%) underwent repeat recanalization by balloon dilation with or without stents. Cumulative 1-, 5-, and 10-year primary patency rates were 94%, 89%, and 66%. Alanine transaminase and alkaline phosphatase levels were independent risk factors for reocclusion. Cumulative 1-, 5-, and 10-year survival rates were 90%, 86%, and 86%. Child-Pugh score and reocclusion were independent predictors of survival. CONCLUSIONS: Percutaneous vena caval balloon dilation and stent placement with thrombus aspiration and thrombolytic therapy is safe and effective for treatment of patients with BCS and IVC thrombosis.
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Angioplastia de Balón , Síndrome de Budd-Chiari/terapia , Trombectomía , Terapia Trombolítica , Vena Cava Inferior , Angioplastia de Balón/efectos adversos , Angioplastia de Balón/instrumentación , Angioplastia de Balón/mortalidad , Síndrome de Budd-Chiari/diagnóstico por imagen , Síndrome de Budd-Chiari/mortalidad , Síndrome de Budd-Chiari/fisiopatología , China , Femenino , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Flebografía , Modelos de Riesgos Proporcionales , Radiografía Intervencional , Recurrencia , Estudios Retrospectivos , Factores de Riesgo , Stents , Succión , Trombectomía/efectos adversos , Trombectomía/mortalidad , Terapia Trombolítica/efectos adversos , Terapia Trombolítica/mortalidad , Factores de Tiempo , Resultado del Tratamiento , Grado de Desobstrucción Vascular , Vena Cava Inferior/diagnóstico por imagen , Vena Cava Inferior/fisiopatologíaRESUMEN
OBJECTIVES: To evaluate the feasibility and efficacy of transjugular intrahepatic portosystemic shunt (TIPS) for extrahepatic portal venous obstruction with recurrent variceal bleeding in children. METHODS: From November 2005 to December 2013, 28 consecutive paediatric patients with extrahepatic portal venous obstruction treated with TIPS for recurrent variceal bleeding refractory to medical/endoscopic therapy and/or surgical treatment in a tertiary-care centre were followed until last clinical evaluation or death. The median follow-up time was 36.0 months (range 4.0-106.0 months). RESULTS: Seventeen boys and 11 girls of ages 7.1 to 17.9 years (median 12.3 years) weighing 19.0 to 62.0 kg (median 33.5 kg) were treated. TIPS was successfully placed in 17 of 28 (60.7%) patients via a transjugular approach alone (nâ=â4), a combined transjugular/transhepatic approach (nâ=â9), or a combined transjugular/transsplenic approach (nâ=â4). Shunt dysfunction occurred in 6 of 17 (35.3%) patients. The cumulative 1- and 3-year free-from-variceal-rebleeding rates in TIPS success group were higher than those in TIPS failure group (75.0% and 67.5% vs 45.5% and 18.2%, respectively, Pâ=â0.0075). Compared with the TIPS failure group, the improvements in the height-for-age z scores were greater in the TIPS success group (Pâ=â0.017). Procedure-related complication occurred in 1 patient (3.6%), and no episode of post-TIPS hepatic encephalopathy occurred in any patient. Except 1 patient in the TIPS success group died at 115 postoperative days, all patients were alive. CONCLUSIONS: TIPS is feasible and effective in children with extrahepatic portal venous obstruction and recurrent variceal bleeding. TIPS could represent a less-invasive alternative to traditional surgical portosystemic shunting or a valuable treatment option if surgery and endoscopic treatment failed.
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Várices Esofágicas y Gástricas/cirugía , Hemorragia Gastrointestinal/cirugía , Hipertensión Portal/cirugía , Vena Porta/cirugía , Derivación Portosistémica Intrahepática Transyugular , Enfermedades Vasculares/cirugía , Adolescente , Niño , Endoscopía , Várices Esofágicas y Gástricas/etiología , Femenino , Hemorragia Gastrointestinal/etiología , Encefalopatía Hepática , Humanos , Hipertensión Portal/etiología , Masculino , Pediatría , Vena Porta/patología , Recurrencia , Resultado del Tratamiento , Enfermedades Vasculares/complicacionesRESUMEN
Bifidobacteria are commensal microorganisms of the human and animal intestinal tract, and their surface proteins can mediate bacterial communication and chemical sensing in the environment, as well as facilitate interactions between bacteria and the host. However, a systematic study of the outer surface-associated proteome of bifidobacteria has not been undertaken. In the present study, the proteins located on the surface of Bifidobacterium animalis ssp. lactis KLDS 2.0603 were systematically identified by a nongel proteomic approach, which consisted of the shaving of the bacterial surface with trypsin and an analysis of the released peptides by liquid chromatography-tandem mass spectrometry. A total of 105 surface-associated proteins were found, of which 15 proteins could potentially be involved in adhesion and interactions between bifidobacteria and the host. The proteins related to adhesion and interaction between bacteria and the host include pilus structure proteins (Fim A, Fim B), 10 moonlighting proteins, an NLP/P60 family protein, an immunogenic secreted protein, and a putative sugar-binding secreted protein. The results provide the basis for future studies on the molecular mechanisms of the interactions between bifidobacteria and the host.
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Proteínas Bacterianas/genética , Bifidobacterium animalis/genética , Proteínas de la Membrana/genética , Azidas/química , Proteínas Bacterianas/metabolismo , Bifidobacterium animalis/metabolismo , Espectrometría de Masas , Proteínas de la Membrana/metabolismo , Microscopía Electrónica de Rastreo , Microscopía Electrónica de Transmisión , Propidio/análogos & derivados , Propidio/química , Reacción en Cadena en Tiempo Real de la Polimerasa , Tripsina/químicaRESUMEN
Foodborne pathogens are a leading cause of mortality worldwide. Therefore, strategies focused on functional foods are urgently required to tackle this issue. As a result, camel milk is one of the most important traditional functional foods since it contains a variety of bioactive components, which all have antimicrobial activity against foodborne pathogens. The study aims to investigate the potential antimicrobial activity of raw camel milk against foodborne pathogens in both in vitro agar well diffusion and infected mice, especially Listeria monocytogenes, Staphylococcus aureus, Salmonella Typhimurium and Escherichia coli, particularly in societies that rely on consuming camel milk in its raw form. A total of eighty C57BL/6 mice were divided into ten groups and gavaged with or without camel milk for two consecutive weeks. A blood plasma analysis and serum insulin levels were measured. Histological investigations of the liver, pancreas, kidney, spleen, lung and testicles were also performed. In both in vivo and in vitro studies when compared to other pathogenic bacteria, E. coli was the most affected by raw camel milk, with a significant clear zone of 2.9 ± 0.13 cm in vitro and in all measured parameters in vivo (p < 0.05). As a result, we advocated for further research to improve camel breeding, raise milk yield and extend its reproductive capability as one of the most important farm animals.
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Antiinfecciosos , Listeria monocytogenes , Animales , Ratones , Leche/microbiología , Camelus , Escherichia coli , Alimentos Funcionales , Microbiología de AlimentosRESUMEN
Aiming at the repairing of keyhole defects after friction stir welding of complex structures, a new method combined with tungsten inert gas welding (TIG) and friction stir processing (FSP) was proposed. The results showed that the pre-filling wire of TIG can completely fill the volumetric keyhole. FSP can refine the coarse grain area into equiaxial grains due to dynamic recrystallization, while some pore defects are eliminated. The interface bonding quality is high. The microhardness of the repairing zone with FSP is significantly stronger than that of the untreated parts. Compared to direct TIG repairing, the introduction of FSP transformed the fracture from brittle fracture to ductile fracture, and the tensile strength of the joint was increased by 131.7%, realizing the high-quality repairing of keyhole defects in 2195 Al-Li alloy.
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Friction stir welding was utilized to obtain high-quality SUS301L stainless steel joints, whose mechanical and corrosion properties were thoroughly evaluated. Sound joints were obtained with a wide range of rotational velocities from 400 to 700 rpm. The microstructures of the stir zone primarily consisted of austenite and lath martensite without the formation of detrimental phases. The ultimate tensile strength of the welded joints improved with higher rotational velocities apart from 400 rpm. The ultimate tensile strength reached 813 ± 16 MPa, equal to 98.1 ± 1.9% of the base materials (BMs) with a rotational velocity of 700 rpm. The corrosion resistance of the FSW joints was improved, and the corrosion rates related to uniform corrosion with lower rotational velocities were one order of magnitude lower than that of the BMs, which was attributed to the lower martensite content. However, better anti-pitting corrosion performance was obtained with a high rotational velocity of 700 rpm, which was inconsistent with the uniform corrosion results. It could be speculated that a higher martensitic content had a negative effect on the uniform corrosion performance, but had a positive effect on the improvement of the anti-pitting corrosion ability.
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To obtain high-quality joints of Al/steel dissimilar materials, a new extrinsic-riveting friction stir lap welding (ERFSLW) method was proposed combining the synthesis advantages of mechanical riveting and metallurgical bonding. SiC-reinforced Al matrix composite bars were placed in the prefabricated holes in Al sheets and steel sheets, arranged in a zigzag array. The bars were stirred and mixed with Al sheets under severe plastic deformation (SPD), forming composite rivets to strengthen the mechanical joining. SiC particles were uniformly dispersed in the lower part of the welding nugget zone (WNZ). The smooth transition between the SiC mixed zone and extrinsic-riveting zone (ERZ) ensured the metallurgical bonding. The maximum tensile shear load of the joints reached 7.8 kN and the maximum load of the weld per unit length was 497 N/mm. The fracture occurred at the interface between the rivets and steel sheets rather than the conventional Al/steel joining interface. Moreover, ERFSLW can prolong the service life of joints due to three fracture stages. This method can be further extended to the welding of other dissimilar materials that conform to the model of "soft/hard".
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In the quest for excellent light-structural materials that can withstand mechanical extremes for advanced applications, design and control of microstructures beyond current material design strategies have become paramount. Herein, we design a coherent shell at incoherent precipitates in the 2195 aluminum alloy with multi-step metastable phase transitions. A high local strain rate via a neoteric deformation-driven metallurgy method facilitated the diffusion of Li. The original T1 (Al2CuLi) phases were transformed into coherent-shell (Li-rich) irregular-coated incoherent-core (Al2Cu) precipitates. The ultimate tensile strength and elongation reached 620 ± 18 MPa and 22.3 ± 2.2%, exhibiting excellent strength-ductility synergy. Grain boundaries, dislocation, solid solution atoms, and precipitates all contributed to the yield strength of the materials, among which precipitates occupied a dominant position, contributing approximately 56.07%. A new "incoherent-coherent interact" strain-hardening mechanism was also clarified, which was believed to be promoted in other heat-treatable alloy systems, especially with multi-step metastable phase transitions.
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This study reports the structure-activity relationships of a unique subclass IIb bacteriocin, plantaricin EvF, which consists of two peptide chains and possesses potent antimicrobial activity. Because the plantaricin Ev peptide chain lacks an α-helix structure, plantaricin EvF is unable to exert its antimicrobial activity through helix-helix interactions like typical subclass IIb bacteriocins. We have shown by various structural evaluation methods that plantaricin Ev can be stabilized by hydrogen bonding at amino acid residues R3, V12, and R13 to the N-terminal region of plantaricin F. This binding gives plantaricin EvF a special spade-shaped structure that exerts antimicrobial activity. In addition, the root-mean-square deviations (RMSDs) of the amino acid residues Y6, F8, and R13 of plantaricin Ev pre- and post-binding were 1.512, 1.723, and 1.369, respectively, indicating that they underwent large structural changes. The alanine scanning experiments demonstrated the important role of the above key amino acids in maintaining the structural integrity of plantaricin EvF. This study not only reveals the unique structural features of plantaricin EvF, but also provides an insight into the structure-activity relationships of subclass IIb bacteriocins.
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The present study was planned to explore the effect of Lactobacillus (L.) acidophilus on the T helper-17 (Th17) immune response in a mouse model of ß-lactoglobulin (ß-lg) allergy. Bovine ß-lg sensitised BALB/c mice were orally administered with different doses of heat-killed L. acidophilus (low, 5×10(7) colony forming unit (CFU); medium, 5×10(8) CFU; high, 5×10(9) CFU) in 200 µL of phosphate buffered saline (PBS) three times a week, starting from 1 week before ß-lg sensitisation for 4 weeks. After the allergen challenge, the numbers of blood eosinophils and neutrophils were examined by light microscope; the levels of cytokine (interleukin (IL)-12, IL-4, tumor growth factor (TGF)-ß, IL-10, IL-6 and IL-17A), total immunoglobulin E (IgE) and ß-lg-specific IgE contents in the serum were measured with enzyme-linked immunosorbent assay (ELISA); The mRNA expression levels of TGF-ß, IL-17A,CD25, Foxp3, retinoic acid-related orphan receptor γt (RORγt) and IL-10 were analyzed using real-time polymerase chain reaction (PCR). The results showed that oral administration of L. acidophilus suppressed hypersensitivity responses, attenuated the numbers of inï¬ammatory cells and inhibited IgE production. We found up-regulation of TGF-ß and down-regulation of IL-17A in the serum of L. acidophilus-treated group, along with IL-6 levels was significantly decreased than that of the allergy group (p<0.05). Moreover, the mRNA expression levels of CD25, forkhead box P3 and TGF-ß were significantly higher in the spleen of L. acidophilus-treated group, while the mRNA expression levels of IL-17A, RORγt and IL-10 were significantly lower than that in the allergy group (p<0.05). In conclusion, the suppression of major allergic symptoms by oral administration of L.acidophilus was probably due to improve the regulatory T (Treg)/Th17 balance and inhibit the IL-6 production.
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Alérgenos/efectos adversos , Antialérgicos/administración & dosificación , Lactobacillus acidophilus , Lactoglobulinas/efectos adversos , Hipersensibilidad a la Leche/terapia , Administración Oral , Animales , Bovinos , Citocinas/sangre , Citocinas/genética , Femenino , Expresión Génica , Calor , Inmunoglobulina E/sangre , Subunidad alfa del Receptor de Interleucina-2/genética , Recuento de Leucocitos , Ratones , Ratones Endogámicos BALB C , Hipersensibilidad a la Leche/etiología , Hipersensibilidad a la Leche/inmunología , Miembro 3 del Grupo F de la Subfamilia 1 de Receptores Nucleares/genética , Células Th17/inmunología , Factor de Crecimiento Transformador beta/genéticaRESUMEN
Multigrain products can prevent the occurrence of chronic noninfectious diseases such as hyperglycemia and hyperlipidemia. In this study, multigrain dough fermented by lactic acid bacteria (LAB) was used for the preparation of good-quality steamed multigrain bread, and its effects on type 2 diabetes were investigated. The results showed that the multigrain dough fermented with LAB significantly enhanced the specific volume, texture, and nutritional value of the steamed bread. The steamed multigrain bread had a low glycemic index and was found to increase liver glycogen and reduce triglyceride and insulin levels, while improving oral glucose tolerance and blood lipid levels in diabetic mice. The steamed multigrain bread made from dough fermented with LAB had comparable effects on type 2 diabetes to steamed multigrain bread prepared from dough fermented without LAB. In conclusion, multigrain dough fermentation with LAB improved the quality of the steamed bread while preserving its original efficacy. These findings provide a novel approach to the production of functional commercial foods.
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In this study, a novel homogeneous mannose-rich polysaccharide named EPS-1 from the fermentation broth of Bifidobacterium breve H4-2 was isolated and purified by anion exchange column chromatography and gel column chromatography. The primary structure of EPS-1 was analyzed by high-performance liquid chromatography, Fourier-transform infrared spectroscopy, gas chromatography-mass spectrometry, and nuclear magnetic resonance. The results indicated that EPS-1 had typical functional groups of polysaccharides. EPS-1 with an average molecular weight of 3.99 × 104 Da was mainly composed of mannose (89.65%) and glucose (5.84%). The backbone of EPS-1 was â2,6)-α-d-Manp-(1â2)-α-d-Manp-(1â2,6)-α-d-Manp-(1â2)-α-d-Manp-(1â2,6)-α-d-Manp-(1â6)-α-d-Glcp-(1â simultaneously containing two kinds of branched chains (α-d-Manp-(1â3)-α-d-Manp-(1â and α-d-Manp-(1â). Besides, EPS-1 had a triple-helical conformation and exhibited excellent thermal stability. Moreover, the immunomodulatory activity of EPS-1 was evaluated by RAW 264.7 cells. Results indicated that EPS-1 significantly enhanced the viability of RAW 264.7 cells. EPS-1 could also be recognized by toll-like receptor 4, thereby activating the nuclear factors-κB (NF-κB) signaling pathway, promoting phosphorylation of related nuclear transcription factors, improving cell phagocytic activity, and promoting the secretion of NO, IL-6, IL-1ß, and TNF-α. Thus, EPS-1 could activate the TLR4-NF-κB signaling pathway to emerge immunomodulatory activity on macrophages. The above results indicate that EPS-1 can serve as a potential immune-stimulating polysaccharide.
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Bifidobacterium breve , Manosa , Animales , Ratones , Manosa/metabolismo , Bifidobacterium breve/metabolismo , FN-kappa B/genética , FN-kappa B/metabolismo , Polisacáridos/química , Macrófagos/metabolismo , Células RAW 264.7 , Peso MolecularRESUMEN
OBJECTIVE: We investigated the correlation between the in vitro immune profiling of 5 lactobacilli strains and their in vivo protective effect in a mouse beta-lactoglobulin (BLG) allergy model for selecting the candidate strains with potential anti-allergy activity. METHODS: In vitro immunomodulation was assessed by measuring interleukin (IL)-4 and interferon gamma (IFN-gamma) release by primary lymphocytes stimulated with 5 active/heat-killed lactobacilli. A mice model of beta-lactoglobulin allergy was then used to evaluate the alleviating allergy capacity of the same set of strains. The rats were randomly divided into blank group, BLG allergy group and different lactobacilli strains group. The total IgE and BLG-specific IgE contents in the serum of rats were measured with ELISA. Splenic lymphocytes were isolated and cultured in vitro, the levels of Thl/Th2 type cytokine were detected by ELISA. RESULTS: Protection of BLG-induced allergy was strain-specific. The strains displaying an in vitro capacity to induce higher levels of the Thl type cytokine (IFN-gamma) and lower levels of the Th2 type cytokine (IL-4), significantly decreased the levels of total IgE and BLG-IgE in allergic rat serum (P<0.05). In contrast, strains leading to a low IFN-gamma/IL-4 cytokine ratio could not significantly attenuate allergic symptoms. CONCLUSION: We could predict the in vivo protective capacity of the studied lactobacilli strains based on the cytokine profile established in vitro. Oral consumption of specific strain may be effective in preventing and alleviating BLG allergic symptoms by the improvement of the Th1/Th2 cell balance toward Th1 dominance, and the inhibition of IgE production.