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1.
Int J Mol Sci ; 19(4)2018 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-29601474

RESUMEN

Leucine-rich repeat-containing G protein-coupled receptor 5 (LGR5) and B-cell-specific Moloney murine leukemia virus insertion site 1 (BMI1) are markers of fast-cycling and quiescent intestinal stem cells, respectively. To determine the functions of these proteins in large animals, we investigated their effects on the proliferation of intestinal epithelial cells from pigs. Our results indicated that LGR5 and BMI1 are highly conserved proteins and that the pig proteins have greater homology with the human proteins than do mouse proteins. Overexpression of either LGR5 or BMI1 promoted cell proliferation and WNT/ß-catenin signaling in pig intestinal epithelial cells (IPEC-J2). Moreover, the activation of WNT/ß-catenin signaling by recombinant human WNT3A protein increased cell proliferation and LGR5 and BMI1 protein levels. Conversely, inhibition of WNT/ß-catenin signaling using XAV939 reduced cell proliferation and LGR5 and BMI1 protein levels. This is the first report that LGR5 and BMI1 can increase proliferation of pig intestinal epithelial cells by activating WNT/ß-catenin signaling.


Asunto(s)
Proliferación Celular/fisiología , Complejo Represivo Polycomb 1/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Vía de Señalización Wnt/fisiología , beta Catenina/metabolismo , Animales , Proliferación Celular/efectos de los fármacos , Proliferación Celular/genética , Células Epiteliales/efectos de los fármacos , Células Epiteliales/metabolismo , Compuestos Heterocíclicos con 3 Anillos/farmacología , Humanos , Intestinos/citología , Complejo Represivo Polycomb 1/genética , Receptores Acoplados a Proteínas G/genética , Porcinos , Vía de Señalización Wnt/efectos de los fármacos , Vía de Señalización Wnt/genética , Proteína Wnt3A/genética , Proteína Wnt3A/metabolismo
2.
J Pediatr Gastroenterol Nutr ; 59(2): 264-9, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24625969

RESUMEN

OBJECTIVES: Butyrate is well known to induce apoptosis in differentiating intestinal epithelial cells. The present study was designed to examine the role of p38 mitogen-activated protein kinase (MAPK) in butyrate-induced intestinal barrier impairment. METHODS: The intestinal barrier was determined by measuring the transepithelial electrical resistance (TER) in a Caco-2 cell monolayer model. The permeability was determined by measuring transepithelial passage of fluorescein isothiocyanate-conjugated inulin (inulin-FITC). The morphology of the monolayers was examined with scanning electron microscopy. The apoptosis status was determined by annexin V-FITC labeling and flow cytometry. The activity of p38 MAPK was determined by the phosphorylation status of p38 with Western blotting. RESULTS: Butyrate at 5 mM increases the apoptosis rate of Caco-2 cells and induces impairment of intestinal barrier functions as determined by decreased TER and increased inulin-FITC permeability. Butyrate treatment activates p38 MAPK in a concentration- and time-dependent manner. SB203580, a specific p38 inhibitor, inhibits butyrate-induced Caco-2 cell apoptosis. Treatment of SB203580 significantly attenuates the butyrate-induced impairment of barrier functions in the Caco-2 cell monolayer model. CONCLUSIONS: p38 MAPK can be activated by butyrate and is involved in the butyrate-induced apoptosis and impairment of intestinal barrier function. Inhibition of p38 MAPK can significantly attenuate butyrate-induced intestinal barrier dysfunction.


Asunto(s)
Apoptosis , Butiratos/efectos adversos , Absorción Intestinal , Enfermedades Intestinales/enzimología , Mucosa Intestinal/enzimología , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo , Anexina A5/metabolismo , Apoptosis/efectos de los fármacos , Células CACO-2 , Impedancia Eléctrica , Inhibidores Enzimáticos/farmacología , Fluoresceína-5-Isotiocianato/metabolismo , Humanos , Imidazoles/farmacología , Absorción Intestinal/efectos de los fármacos , Enfermedades Intestinales/metabolismo , Mucosa Intestinal/metabolismo , Inulina/metabolismo , Permeabilidad , Fosforilación , Piridinas/farmacología , Proteínas Quinasas p38 Activadas por Mitógenos/antagonistas & inhibidores
3.
Rev Sci Instrum ; 95(2)2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38310639

RESUMEN

A specially designed experimental apparatus suitable for commercial superconductor magnet is used for solidification and in situ characterization of the nucleation behavior of high-melting metals. In order to carry out solidification experiments under a high magnetic field (HMF), the sample cell in the experimental device has two stations for repeated verification experiments of two same samples or comparative experiments of two different samples. Meanwhile, a metal specimen and a reference (α-Al2O3) are placed in the sample cell to characterize the nucleation behavior in situ. Using this experimental device, the nucleation behaviors of Al-7wt. %Si alloy and pure Cu under a HMF were investigated. The results show that the undercoolings of Al-7wt. %Si alloy and pure Cu increase under the HMF. Furthermore, the applied HMF decreases the activation energy of Al-7wt. %Si alloy and increases the nucleation work. Based on the magnetohydrodynamic effect, the change in undercooling and nucleation work could be partly attributed to the restrained thermal convection by the HMF in this study.

4.
Clin Biochem ; 123: 110701, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38048899

RESUMEN

BACKGROUND: Human epididymis protein 4 (HE4) is a promising tumor biomarker primarily utilized for the detection of ovarian cancer. However, its potential as a novel diagnostic indicator for immunoglobulin A nephropathy (IgAN) remains unknown. The objective of this study was to investigate the feasibility of serum HE4 as a novel biomarker for patients with IgAN. METHODS: This study enrolled a total of 89 hospitalized patients with IgAN at Peking University Shenzhen Hospital between July 2020 and December 2022, along with 60 healthy control subjects matched for sex and age without evidence of comorbidities. Serum HE4 levels were measured using the Abbott Alinity automated immune analyzer, and the correlation between serum HE4 levels and biochemical markers of renal damage as well as clinicopathologic features in IgAN patients were analyzed. RESULTS: In this study, serum HE4 levels were significantly elevated in patients with IgAN compared to healthy controls (116.43 ± 103.61 pmol/L vs. 35.57 ± 9.33 pmol/L, p < 0.001). There was a positive correlation between serum HE4 levels and blood urea nitrogen (r = 0.58, p < 0.001), creatinine (r = 0.73, p < 0.001), cystatin C (r = 0.82, p < 0.001), ß2-microglobulin (r = 0.77, p < 0.001), α1-microglobulin (r = 0.75, p < 0.001), and glomerulosclerosis ratio (r = 0.56, p < 0.001). Conversely, a negative correlation was observed between serum HE4 levels and hemoglobin (r = -0.42, p < 0.001), albumin (r = -0.44, p < 0.001) and estimated glomerular filtration rate (eGFR) (r = -0.83, p < 0.001). In HE4+ IgAN patients, a higher glomerulosclerosis ratio (p < 0.01) and lower eGFR levels (p < 0.001) were observed compared to HE4- patients. Furthermore, patients with higher pathological classification grade also had higher serum HE4 levels. CONCLUSIONS: Serum HE4 levels were significantly associated with both renal function and the pathological classification of patients with IgAN, indicating that HE4 may serve as a promising biomarker for assessing the severity of IgAN.


Asunto(s)
Glomerulonefritis por IGA , Humanos , Biomarcadores , Biomarcadores de Tumor , Tasa de Filtración Glomerular , Riñón/patología , Gravedad del Paciente
5.
Zookeys ; 1179: 299-311, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37745623

RESUMEN

Amphioctopusaegina is an economically important species that has been intensively exploited in the marine areas along the Chinese coast. However, the genetic variation and population genetic structure, which would provide valuable information for their fisheries management, have rarely been investigated. In this study, the genetic variation within and among four A.aegina populations throughout its full distribution range were estimated based on mitochondrial cytochrome b DNA sequences. Our results indicated low (Qinzhou) to high (Dongshan) genetic diversities among the four populations. Analysis of molecular variance (AMOVA), ΦST statistics, phylogenetic tree and haplotype networks revealed two significant (p < 0.01) divergent lineages with a ΦST value of 0.7116 between them, one from a population in Qinzhou and the other from the remaining three populations of Dongshan, Huizhou and Zhanjiang. However, the low genetic distance (0.0032) and only two fixed substitutions between them suggest their recent divergence is possibly due to the last glacial period barriers to gene flow produced by the Leizhou Peninsula. The observed lineage divergence suggests that populations of A.aegina in China are genetically subdivided and may represent evolutionary lineages that should be managed individually.

6.
Mol Neurobiol ; 60(6): 3345-3364, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36853430

RESUMEN

Defective autophagy relates to the pathogenesis of Parkinson's disease (PD), a typical neurodegenerative disease. Our recent study has demonstrated that PD toxins (6-OHDA, MPP+, or rotenone) induce neuronal apoptosis by impeding the AMPK/Akt-mTOR signaling. Here, we show that treatment with 6-OHDA, MPP+, or rotenone triggered decreases of ATG5/LC3-II and autophagosome formation with a concomitant increase of p62 in PC12, SH-SY5Y cells, and primary neurons, suggesting inhibition of autophagy. Interestingly, overexpression of wild-type ATG5 attenuated the inhibitory effect of PD toxins on autophagy, reducing neuronal apoptosis. The effects of PD toxins on autophagy and apoptosis were found to be associated with activation of PTEN and inactivation of Akt. Overexpression of dominant negative PTEN, constitutively active Akt and/or pretreatment with rapamycin rescued the cells from PD toxins-induced downregulation of ATG5/LC3-II and upregulation of p62, as well as consequential autophagosome diminishment and apoptosis in the cells. The effects of PD toxins on autophagy and apoptosis linked to excessive intracellular and mitochondrial hydrogen peroxide (H2O2) production, as evidenced by using a H2O2-scavenging enzyme catalase, a mitochondrial superoxide indicator MitoSOX and a mitochondria-selective superoxide scavenger Mito-TEMPO. Furthermore, we observed that treatment with PD toxins reduced the protein level of Parkin in the cells. Knockdown of Parkin alleviated the effects of PD toxins on H2O2 production, PTEN/Akt activity, autophagy, and apoptosis in the cells, whereas overexpression of wild-type Parkin exacerbated these effects of PD toxins, implying the involvement of Parkin in the PD toxins-induced oxidative stress. Taken together, the results indicate that PD toxins can elicit mitochondrial H2O2, which can activate PTEN and inactivate Akt leading to autophagy inhibition-dependent neuronal apoptosis, and Parkin plays a critical role in this process. Our findings suggest that co-manipulation of the PTEN/Akt/autophagy signaling by antioxidants may be exploited for the prevention of neuronal loss in PD.


Asunto(s)
Neuroblastoma , Enfermedades Neurodegenerativas , Enfermedad de Parkinson , Humanos , Enfermedad de Parkinson/patología , Peróxido de Hidrógeno/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Serina-Treonina Quinasas TOR/metabolismo , Rotenona/farmacología , Rotenona/metabolismo , Superóxidos/metabolismo , Enfermedades Neurodegenerativas/metabolismo , Oxidopamina/farmacología , Neuroblastoma/patología , Neuronas/metabolismo , Apoptosis , Autofagia , Mitocondrias/metabolismo , Fosfohidrolasa PTEN/metabolismo
7.
Zhonghua Wai Ke Za Zhi ; 50(9): 839-42, 2012 Sep.
Artículo en Zh | MEDLINE | ID: mdl-23157963

RESUMEN

OBJECTIVES: To study the expression of nicotinamide phosphoribosyl transferase (Nampt) and vascular endothelial growth factor-A (VEGF-A) in gastric carcinoma and investigate their correlations to clinicopathologic features and prognostic significance. METHODS: The proteins of Nampt and VEGF-A in 68 specimens of gastric carcinoma and 59 specimens normal gastric tissue were detected by immunohistochemistry during January 2000 to December 2004, and the 68 patients were followed up. RESULTS: Nampt protein was detected in the cytoplasm of both tissues, and Nampt in gastric carcinoma (13 ± 5) were significantly higher than that in normal gastric tissue (6 ± 3) (t = 7.46, P < 0.01). The expression of Nampt was correlated to invasive depth (F = 4.693, P = 0.034), lymph node metastasis (F = 4.027, P = 0.049), clinical TNM stage (F = 9.979, P = 0.002), but not to gender, age, tumor location, tumor size, differentiation (P > 0.05). The expression of Nampt is correlated with survival of patients that underwent surgical resection for gastric cancer. The survival rate of patients in negative of Nampt was very higher than that of the positive patients, and its co-expression with VEGF-A showed a trend towards poorer survival. The positive correlation was found between the expression of Nampt and VEGF-A in gastric carcinoma (r = 0.293, P = 0.015). CONCLUSIONS: The expression of Nampt is positively correlated to that of VEGF-A in gastric carcinoma. The correlation between the expression of Nampt and VEGF-A in gastric carcinoma plays an important role cooperatively in carcinogenesis, development and metastasis of gastric carcinoma.


Asunto(s)
Citocinas/metabolismo , Nicotinamida Fosforribosiltransferasa/metabolismo , Neoplasias Gástricas/metabolismo , Factor A de Crecimiento Endotelial Vascular/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Metástasis Linfática , Masculino , Persona de Mediana Edad , Pronóstico , Neoplasias Gástricas/patología , Tasa de Supervivencia
8.
ACS Appl Mater Interfaces ; 14(2): 2782-2793, 2022 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-34995443

RESUMEN

The sluggish charge transport kinetics that exist in the energy storage process of all-solid-state supercapacitors (ASSSCs) can be improved by designing open hierarchical porous structures for binder-free electrodes. Herein, a template-directed strategy is developed to fabricate open hierarchical porous Ni-Co-Zn-P nanoplate arrays (NCZP6T) through phosphating the electrodeposited NiCo-LDH nanosheets loaded on a template. At first, porous conductive NiZn alloy nanoplate arrays are rationally devised as the template by a strong magnetic field (SMF)-assisted electrodeposition. The Lorentz force caused by coupling the SMF with the electrical current induces a magnetohydrodynamic (MHD) flow (including the micro-MHD flow), which homogenizes the deposition coating, tunes the nucleation and growth of the NiZn alloy, and produces pores in the nanoplates. The open hierarchical porous structure offers a larger specific surface area and pore volume for accelerating charge transport and gives a synergistic effect between the inner porous conductive NiZn array template and the outer electrochemical active phosphides for high-performance hybrid ASSSCs. Accordingly, the battery-type electrode of NCZP6T shows a much higher specific capacitance of 3.81 F cm-2 at 1 mA cm-2, enhanced rate capability, and remarkable cycling stability at progressively varying current densities. Finally, the NCZP6T//FeS ASSSC delivers a high energy density of 77 µW h cm-2 at a large power density of 12 mW cm-2, outperforming most state-of-the-art supercapacitors.

9.
Environ Sci Technol ; 45(22): 9531-7, 2011 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-21961564

RESUMEN

Methane (CH(4)) may be generated via microbial and nonmicrobial mechanisms. Nonmicrobial CH(4) is also ubiquitous in nature, such as in biomass burning, the Earth's crust, plants, and animals. Relative to microbial CH(4), nonmicrobial CH(4) is less understood. Using fresh (living) and dried (dead) leaves and commercial structural compounds (dead) of plants, a series of laboratory experiments have been conducted to investigate CH(4) emissions under aerobic and anaerobic conditions. CH(4) emissions from fresh leaves incubated at ambient temperatures were nonmicrobial and enhanced by anaerobic conditions. CH(4) emissions from dried leaves incubated at rising temperature ruled out a microbial-mediated formation pathway and were plant-species-dependent with three categories of response to oxygen levels: enhanced by aerobic conditions, similar under aerobic and anaerobic conditions, and enhanced by anaerobic conditions. CH(4) emissions in plant structural compounds may help to fully understand nonmicrobial CH(4) formation in plant leaves. Experiments of reactive oxygen species (ROS) generator and scavengers indicate that ROS had a significant role in nonmicrobial CH(4) formation in plant material under aerobic and anaerobic conditions. However, the detailed mechanisms of the ROS were uncertain.


Asunto(s)
Metano/metabolismo , Hojas de la Planta/metabolismo , Plantas/metabolismo , Aerobiosis , Anaerobiosis , Oxígeno/metabolismo
10.
Clin Transl Immunology ; 10(2): e1254, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33708385

RESUMEN

OBJECTIVES: Genetic and epigenetic mechanisms regulate antimicrobial immunity against Mycobacterium tuberculosis (Mtb) infection. METHODS: The present study assessed circular RNA TRAPPC6B (circTRAPPC6B) for antimicrobial immune functions and defined mechanisms wherein circTRAPPC6B regulates Mtb growth, autophagy and microRNA in macrophages. RESULTS: The Mtb infection of monocytes/macrophages resulted in a significantly decreased level of circTRAPPC6B that inhibited intracellular Mtb growth in macrophages. Conversely, circTRAPPC6B expression enhanced autophagy or autophagy-associated protein LC3-II production in Mtb-infected macrophages. circTRAPPC6B-enhanced autophagy aggregation or sequestration was also observed in fluorescence in situ hybridisation (FISH) analysis and confocal imaging. Mechanistically, circTRAPPC6B targets an inhibiting element miR-874-3p, as shown by bioinformatics, dual-luciferase reporter gene analysis and pull-down assay, respectively. Notably, miR-874-3p prohibited autophagy via suppressing autophagy protein ATG16L1 by binding to its 3'-untranslated region (UTR) in Mtb-infected macrophages and thus promoting intracellular Mtb growth. Concurrently, circTRAPPC6B enhanced autophagy in Mtb-infected macrophages by blocking the ability of miR-874-3p to inhibit ATG16L1. Thus, circTRAPPC6B antagonises the ability of miR-874-3p to suppress ATG16L1 expression and activate and enhance autophagy sequestration to restrict Mtb growth in macrophages. CONCLUSION: The current findings suggested that both circTRAPPC6B and miR-874-3p mechanisms can be explored as potential therapeutics against Mtb infection.

11.
Int J Biochem Cell Biol ; 121: 105715, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-32035180

RESUMEN

Cadmium (Cd), a heavy metal pollutant, contributes to neurodegenerative disorders. Recently, we have demonstrated that Cd induction of reactive oxygen species (ROS) causes apoptosis in neuronal cells. Whether X-linked inhibitor of apoptosis protein (XIAP) is involved in Cd-induced ROS-dependent neuronal apoptosis remains unclear. Here, we show that Cd-induced ROS reduced the expression of XIAP, which resulted in up-regulation of murine double minute 2 homolog (MDM2) and down-regulation of p53, leading to apoptosis in PC12 cells and primary neurons. Inhibition of MDM2 with Nutlin-3a reversed Cd-induced reduction of p53 and substantially rescued cells from excess ROS-dependent death. Overexpression of XIAP protected against Cd induction of ROS-dependent neuronal apoptosis. Inhibition of XIAP by Embelin strengthened Cd-induced ROS and apoptosis in the cells. Furthermore, we found that Cd inactivation of XIAP pathway was attributed to Cd induction of mitochondrial ROS, as evidenced by using a mitochondrial superoxide indicator MitoSOX and a mitochondria-targeted antioxidant Mito-TEMPO. Taken together, these results indicate that Cd induces mitochondrial ROS inactivation of XIAP-MDM2-p53 pathway leading to apoptosis in neuronal cells. Our findings suggest that activators of XIAP or modulation of XIAP-MDM2-p53 pathway by antioxidants may be exploited for the prevention of Cd-induced oxidative stress and neurodegenerative diseases.


Asunto(s)
Apoptosis/efectos de los fármacos , Cadmio/efectos adversos , Mitocondrias/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Proteína Inhibidora de la Apoptosis Ligada a X/genética , Humanos
12.
Neuropharmacology ; 175: 108065, 2020 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-32209321

RESUMEN

Cadmium (Cd), a toxic environment contaminant, induces reactive oxygen species (ROS)-mediated neuronal apoptosis and consequential neurodegenerative disorders. Metformin, an anti-diabetic drug, has recently received a great attention owing to its protection against neurodegenerative diseases. However, little is known regarding the effect of metformin on Cd-induced neurotoxicity. Here we show that metformin effectively prevented Cd-evoked apoptotic cell death in neuronal cells, by suppressing Cd activation of c-Jun N-terminal kinases (JNK), which was attributed to blocking Cd inactivation of protein phosphatase 5 (PP5) and AMP-activated protein kinase (AMPK). Inhibition of JNK with SP600125, knockdown of c-Jun, or overexpression of PP5 potentiated metformin's inhibitory effect on Cd-induced phosphorylation of JNK/c-Jun and apoptosis. Activation of AMPK with AICAR or ectopic expression of constitutively active AMPKα strengthened the inhibitory effects of metformin on Cd-induced phosphorylation of JNK/c-Jun and apoptosis, whereas expression of dominant negative AMPKα weakened these effects of metformin. Metformin repressed Cd-induced ROS, thereby diminishing cell death. N-acetyl-l-cysteine enhanced the inhibitory effects of metformin on Cd-induced ROS and apoptosis. Moreover, using Mito-TEMPO, we further demonstrated that metformin attenuated Cd-induced cell death by suppressing induction of mitochondrial ROS. Taken together, these results indicate that metformin prevents mitochondrial ROS inactivation of PP5 and AMPK, thus attenuating Cd-induced JNK activation and apoptosis in neuronal cells. Our data highlight that metformin may be a promising drug for prevention of Cd-induced oxidative stress and neurodegenerative diseases.


Asunto(s)
Apoptosis/efectos de los fármacos , Cadmio/toxicidad , Hipoglucemiantes/administración & dosificación , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Metformina/administración & dosificación , Neuronas/efectos de los fármacos , Especies Reactivas de Oxígeno/metabolismo , Proteínas Quinasas Activadas por AMP/metabolismo , Animales , Femenino , Humanos , Ratones Endogámicos ICR , Neuronas/metabolismo , Proteínas Nucleares/metabolismo , Células PC12 , Fosfoproteínas Fosfatasas/metabolismo , Ratas
13.
Mol Med Rep ; 21(4): 1890-1896, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-32319627

RESUMEN

Numerous studies have suggested that circular RNAs (circRNAs), a type of non­coding RNA lacking 5'­caps and 3'­poly(A) tails, are involved in the biological processes of various human diseases. However, little is known about their functions and diagnostic value in active pulmonary tuberculosis (APTB). The aim of the present study was to examine whether hsa_circ_0001380 is able to serve as a diagnostic biomarker for patients with APTB. The expression level of hsa_circ_0001380 was detected in the peripheral blood of 32 patients with APTB and 31 healthy volunteers by reverse transcription­quantitative PCR. The functional prediction of hsa_circ_0001380 was performed in silico. RNase R was used to detect the stability of hsa_circ_0001380. Finally, the diagnostic value of hsa_circ_0001380 was evaluated by receiver operating characteristic (ROC) curve analysis. The results showed that hsa_circ_0001380 was significantly downregulated in the peripheral blood of patients with APTB. In addition, hsa_circ_0001380 was found to be resistant to RNase R treatment. Moreover, four N6­adenosine methylation modification sites and two potential microRNA binding sites were predicted in silico. Importantly, the area under the ROC curve was 0.9502, which suggested that hsa_circ_0001380 may act as a diagnostic biomarker for APTB. Taken together, the results indicated that circRNA hsa_circ_0001380 was downregulated in the peripheral blood of patients with APTB, and could serve as a diagnostic biomarker.


Asunto(s)
ARN Circular/sangre , Tuberculosis Pulmonar/sangre , Tuberculosis Pulmonar/diagnóstico , Adolescente , Adulto , Anciano , Secuencia de Bases , Biomarcadores/sangre , Regulación hacia Abajo/genética , Femenino , Humanos , Masculino , Persona de Mediana Edad , ARN Circular/genética , Curva ROC , Reproducibilidad de los Resultados , Tuberculosis Pulmonar/genética , Adulto Joven
14.
Sci Rep ; 10(1): 13212, 2020 08 06.
Artículo en Inglés | MEDLINE | ID: mdl-32764544

RESUMEN

IL-35 is an anti-inflammatory cytokine and is thought to be produced by regulatory T (Treg) cells. A previous study found that IL-35 was upregulated in the serum of patients with active tuberculosis (ATB), and IL-35-producing B cells infiltrated to tuberculous granuloma of patients with ATB. Purified B cells from such patients generated more IL-35 after stimulation by antigens of Mycobacterium tuberculosis and secreted more IL-10. However, the function and the underlying mechanisms of IL-35-producing B cells in TB progression have not been investigated. The present study found that the expression of mRNA of IL-35 subsets Ebi3 and p35 was elevated in mononuclear cells from peripheral blood, spleen, bone marrow, and lung tissue in a mouse model infected with Mycobacterium bovis BCG, as tested by real-time polymerase chain reaction. Accordingly, the flow cytometry analysis showed that the counts of a subset of IL-35+ B cells were elevated in the circulating blood and in the spleen, bone marrow, and lung tissue in BCG-infected mice, whereas anti-TB therapy reduced IL-35-producing B cells. Interestingly, BCG infection could drive the infiltration of IL-35-producing B cells into the lung tissue, and the elevated counts of IL-35-producing B cells positively correlated with the bacterial load in the lungs. Importantly, the injection of exogenous IL-35 stimulated the elevation in the counts of IL-35-producing B cells and was associated with the downregulation of Th1/Th17 and upregulation of Foxp3+Treg.The study showed that a subset of IL-35-producing B cells might take part in the downregulation of immune response in mycobacterial infection.


Asunto(s)
Linfocitos B/inmunología , Interleucinas/metabolismo , Pulmón/inmunología , Mycobacterium bovis , Linfocitos T Reguladores/inmunología , Tuberculosis Pulmonar/inmunología , Animales , Antituberculosos/farmacología , Linfocitos B/efectos de los fármacos , Regulación hacia Abajo , Femenino , Factores de Transcripción Forkhead/metabolismo , Interleucina-10/metabolismo , Interleucinas/genética , Pulmón/microbiología , Recuento de Linfocitos , Ratones , Ratones Endogámicos C57BL , ARN Mensajero/metabolismo , Células TH1/inmunología , Células Th17/inmunología , Tuberculosis Pulmonar/metabolismo , Regulación hacia Arriba
15.
Front Immunol ; 11: 518, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32296431

RESUMEN

Little is known about how tuberculosis (TB) impairs dendritic cell (DC) function and anti-TB immune responses. We previously showed that the B and T lymphocyte attenuator (BTLA), an immune inhibitory receptor, is involved in TB pathogenesis. Here, we examined whether BTLA expression in TB affects phenotypic and functional aspects of DCs. Active TB patients exhibited higher expression of BTLA in myeloid dendritic cells (mDCs) and plasmacytoid DCs (pDCs) subsets compared with healthy controls (HCs). BTLA expression was similarly high in untreated TB, TB relapse, and sputum-bacillus positive TB, but anti-TB therapy reduced TB-driven increases in frequencies of BTLA+ DCs. BTLA+ DCs in active TB showed decreased expression of the DC maturation marker CD83, with an increased expression of CCR7 in mDCs. BTLA+ DCs in active TB displayed a decreased ability to express HLA-DR and to uptake foreign antigen, with a reduced expression of the co-stimulatory molecule CD80, but not CD86. Functionally, BTLA+ DCs in active TB showed a decreased production of IL-12 and IFN-α as well as a reduced ability to stimulate allogeneic T-cell proliferative responses. BTLA+ mDCs produced larger amounts of IL-4 and TGF-ß than BTLA- mDCs in both HCs and APT patients. BTLA+ DCs from active TB patients showed a reduced ability to stimulate Mtb antigen-driven Th17 and Th22 polarizations as compared to those from HCs. Conversely, these BTLA+ DCs more readily promoted the differentiation of T regulatory cells (Treg) and Th2 than those from HCs. These findings suggest that TB-driven BTLA expression in DCs impairs the expression of functional DC surrogate markers and suppress the ability of DCs to induce anti-TB Th17 and Th22 response while promoting Th2 and Foxp3+ Tregs.


Asunto(s)
Células Dendríticas/inmunología , Receptores Inmunológicos/inmunología , Linfocitos T Reguladores/inmunología , Células Th2/inmunología , Tuberculosis Pulmonar/inmunología , Adolescente , Adulto , Anciano , Diferenciación Celular/inmunología , Femenino , Humanos , Interferón-alfa/biosíntesis , Interleucina-12/biosíntesis , Interleucina-4/biosíntesis , Activación de Linfocitos/inmunología , Masculino , Persona de Mediana Edad , Factor de Crecimiento Transformador beta/biosíntesis , Adulto Joven
16.
IUCrJ ; 6(Pt 3): 366-372, 2019 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-31098018

RESUMEN

Stress-induced martensitic detwinning and martensitic transformation during step-wise compression in an austenite Ni-Mn-Ga matrix with a martensite cluster under uniaxial loading have been investigated by electron backscatter diffraction, focusing on the crystallographic features of microstructure evolution. The results indicate that detwinning occurs on twins with a high Schmid factor for both intra-plate and inter-plate twins in the hierarchical structure, resulting in a nonmodulated (NM) martensite composed only of favourable variants with [001]NM orientation away from the compression axis. Moreover, the stress-induced martensitic transformation occurs at higher stress levels, undergoing a three-stage transformation from austenite to a twin variant pair and finally to a single variant with increasing compressive stress, and theoretical calculation shows that the corresponding crystallographic configuration is accommodated to the compression stress. The present research not only provides a comprehensive understanding of martensitic variant detwinning and martensitic transformation under compression stress, but also offers important guidelines for the mechanical training process of martensite.

17.
Toxicol Lett ; 305: 19-31, 2019 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-30690062

RESUMEN

The intake of food containing deoxynivalenol frequently causes damage to the intestine, the renewal of which is driven by intestinal stem cells (ISCs). Nevertheless, the toxicity of deoxynivalenol on ISCs and its underlying mechanisms remain to be elucidated. As pigs are the most sensitive animals to deoxynivalenol, we used piglets for investigation in this study. Here, we show that intestinal epithelial cell activity, B cell-specific Moloney murine leukemia virus insertion site 1 (Bmi1) protein level, and Wnt/ß-catenin pathway activity were suppressed with acute expose to deoxynivalenol. We further established a novel system for porcine crypt isolation and ex vivo cultivation. Crypts and crypt cells expanded and budded with typical enteroid morphologies under this system. Our results show that both acute in vivo and in vitro administration of deoxynivalenol significantly decreased enteroid activity. Simultaneously, protein levels of ß-catenin and leucine-rich-repeat-containing G-protein-coupled receptor 5 (Lgr5) in enteroids were reduced by deoxynivalenol exposure. In conclusion, we established a reliable culture system for porcine enteroids and demonstrated for the first time that the activity of ISCs and the Wnt/ß-catenin pathway is sensitively suppressed by acute deoxynivalenol exposure.


Asunto(s)
Yeyuno/efectos de los fármacos , Porcinos , Tricotecenos/toxicidad , Proteínas Wnt/metabolismo , beta Catenina/metabolismo , Animales , Proliferación Celular/efectos de los fármacos , Regulación de la Expresión Génica/efectos de los fármacos , Masculino , Proteínas Wnt/genética , beta Catenina/genética
18.
Mol Immunol ; 112: 175-181, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31170628

RESUMEN

Regulatory B cells (Bregs) have critical roles as a negative regulator of immunity, mainly due to the fact that it secrets high a level of interleukin 10 (IL-10). Recently, a new subset of Bregs was identified as a key source of IL-35, which is an immunosuppressive cytokine and conventionally thought to be secreted by regulatory T cells (Tregs). Our previous study showed that the level of IL-35 in serum was elevated in the patients with active tuberculosis (ATB). However, none of the studies reported that IL-35 is secreted by B cells in ATB patients. In the current study, we found that the mRNA expressions of the both subunits (p35 and Ebi3) of IL-35 by circulating B cells were increased in ATB patients. By using immunohistochemistry and immunofluorescence staining, we found a subset of B cells infiltrated into the tuberculous granuloma of ATB patients also expressed IL-35. Moreover, Mycobacterium tuberculosis (MTB) lysate stimulation assay also demonstrated higher levels of IL-35 were exerted by MTB lysate within purified B cells from healthy control group (HC). Flow cytometry analysis further showed that the IL-35-producing B cells from ATB patients produced a higher level of IL-10. Taken together, IL-35-producing B cells may play a regulatory role during MTB infection by producing IL-10.


Asunto(s)
Linfocitos B Reguladores/inmunología , Interleucina-10/inmunología , Interleucinas/inmunología , Mycobacterium tuberculosis/inmunología , Tuberculosis Pulmonar/inmunología , Adolescente , Adulto , Anciano , Femenino , Humanos , Interferón gamma/inmunología , Pulmón/inmunología , Pulmón/microbiología , Masculino , Persona de Mediana Edad , Linfocitos T Reguladores/inmunología , Linfocitos T Reguladores/microbiología , Tuberculosis Pulmonar/microbiología , Adulto Joven
19.
Sci Total Environ ; 626: 1193-1199, 2018 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-29898526

RESUMEN

Methane (CH4) is widely present in groundwater. Dissolved CH4 in groundwater is less understood when compared with that in wetlands. In this study, the concentrations and origin of dissolved CH4 in groundwater were investigated and the potential importance of groundwater CH4 emissions in arid and semi-arid regions of Inner Mongolia was discussed. Groundwater was extracted from domestic wells using a submersible pump or manual power and was analyzed for CH4 concentrations, δ13C-CH4, and physico-chemical variables. The results show that the concentrations of dissolved CH4 in groundwater had large spatial variability, ranging from 0 to 0.10 mg L-1 with a mean of 0.01 mg L-1 in Xilingol and from 0 to 8.99 mg L-1 with a mean of 1.44 mg L-1 in Xingan-Tongliao. Substantial CH4 concentrations of about 2.5-5.5 mg L-1 were found in central areas of Xingan-Tongliao in the winter and the summer. The δ13C-CH4 of about -85‰ was highly depleted while CH4 concentration was significantly negatively correlated with SO42- concentration, indicating that dissolved CH4 in groundwater was microbial in origin. This study suggests that groundwater as a source of CH4 might have great implications in arid and semi-arid regions worldwide and should deserve more research.

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