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1.
PLoS Pathog ; 19(2): e1011166, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36753521

RESUMEN

Congenital human cytomegalovirus (HCMV) infection causes severe damage to the fetal brain, and the underlying mechanisms remain elusive. Cytokine signaling is delicately controlled in the fetal central nervous system to ensure proper development. Here we show that suppressor of cytokine signaling 3 (SOCS3), a negative feedback regulator of the IL-6 cytokine family signaling, was upregulated during HCMV infection in primary neural progenitor cells (NPCs) with a biphasic expression pattern. From viral protein screening, pUL97 emerged as the viral factor responsible for prolonged SOCS3 upregulation. Further, by proteomic analysis of the pUL97-interacting host proteins, regulatory factor X 7 (RFX7) was identified as the transcription factor responsible for the regulation. Depletion of either pUL97 or RFX7 prevented the HCMV-induced SOCS3 upregulation in NPCs. With a promoter-luciferase activity assay, we demonstrated that the pUL97 kinase activity and RFX7 were required for SOCS3 upregulation. Moreover, the RFX7 phosphorylation level was increased by either UL97-expressing or HCMV-infection in NPCs, suggesting that pUL97 induces RFX7 phosphorylation to drive SOCS3 transcription. We further revealed that elevated SOCS3 expression impaired NPC proliferation and migration in vitro and caused NPCs migration defects in vivo. Taken together, these findings uncover a novel regulatory mechanism of sustained SOCS3 expression in HCMV-infected NPCs, which perturbs IL-6 cytokine family signaling, leads to NPCs proliferation and migration defects, and consequently affects fetal brain development.


Asunto(s)
Infecciones por Citomegalovirus , Citomegalovirus , Humanos , Citomegalovirus/fisiología , Interleucina-6/metabolismo , Proteómica , Factores de Transcripción/metabolismo , Células Madre , Proteína 3 Supresora de la Señalización de Citocinas/metabolismo
2.
J Virol ; 97(5): e0031323, 2023 05 31.
Artículo en Inglés | MEDLINE | ID: mdl-37097169

RESUMEN

Human cytomegalovirus (HCMV) is a leading cause of congenital birth defects. Though the underlying mechanisms remain poorly characterized, mouse models of congenital CMV infection have demonstrated that the neuronal migration process is damaged. In this study, we evaluated the effects of HCMV infection on connexin 43 (Cx43), a crucial adhesion molecule mediating neuronal migration. We show in multiple cellular models that HCMV infection downregulated Cx43 posttranslationally. Further analysis identified the immediate early protein IE1 as the viral protein responsible for the reduction of Cx43. IE1 was found to bind the Cx43 C terminus and promote Cx43 degradation through the ubiquitin-proteasome pathway. Deletion of the Cx43-binding site in IE1 rendered it incapable of inducing Cx43 degradation. We validated the IE1-induced loss of Cx43 in vivo by introducing IE1 into the fetal mouse brain. Noteworthily, ectopic IE1 expression induced cortical atrophy and neuronal migration defects. Several lines of evidence suggest that these damages result from decreased Cx43, and restoration of Cx43 levels partially rescued IE1-induced interruption of neuronal migration. Taken together, the results of our investigation reveal a novel mechanism of HCMV-induced neural maldevelopment and identify a potential intervention target. IMPORTANCE Congenital CMV (cCMV) infection causes neurological sequelae in newborns. Recent studies of cCMV pathogenesis in animal models reveal ventriculomegaly and cortical atrophy associated with impaired neural progenitor cell (NPC) proliferation and migration. In this study, we investigated the mechanisms underlying these NPC abnormalities. We show that Cx43, a critical adhesion molecule mediating NPC migration, is downregulated by HCMV infection in vitro and HCMV-IE1 in vivo. We provide evidence that IE1 interacts with the C terminus of Cx43 to promote its ubiquitination and consequent degradation through the proteasome. Moreover, we demonstrate that introducing IE1 into mouse fetal brains led to neuronal migration defects, which was associated with Cx43 reduction. Deletion of the Cx43-binding region in IE1 or ectopic expression of Cx43 rescued the IE1-induced migration defects in vivo. Our study provides insight into how cCMV infection impairs neuronal migration and reveals a target for therapeutic interventions.


Asunto(s)
Conexina 43 , Infecciones por Citomegalovirus , Citomegalovirus , Proteínas Inmediatas-Precoces , Animales , Humanos , Recién Nacido , Ratones , Conexina 43/genética , Conexina 43/metabolismo , Citomegalovirus/fisiología , Infecciones por Citomegalovirus/metabolismo , Proteínas Inmediatas-Precoces/genética , Proteínas Inmediatas-Precoces/metabolismo , Complejo de la Endopetidasa Proteasomal/metabolismo
3.
Biometrics ; 80(1)2024 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-38497826

RESUMEN

Multiple testing has been a prominent topic in statistical research. Despite extensive work in this area, controlling false discoveries remains a challenging task, especially when the test statistics exhibit dependence. Various methods have been proposed to estimate the false discovery proportion (FDP) under arbitrary dependencies among the test statistics. One key approach is to transform arbitrary dependence into weak dependence and subsequently establish the strong consistency of FDP and false discovery rate under weak dependence. As a result, FDPs converge to the same asymptotic limit within the framework of weak dependence. However, we have observed that the asymptotic variance of FDP can be significantly influenced by the dependence structure of the test statistics, even when they exhibit only weak dependence. Quantifying this variability is of great practical importance, as it serves as an indicator of the quality of FDP estimation from the data. To the best of our knowledge, there is limited research on this aspect in the literature. In this paper, we aim to fill in this gap by quantifying the variation of FDP, assuming that the test statistics exhibit weak dependence and follow normal distributions. We begin by deriving the asymptotic expansion of the FDP and subsequently investigate how the asymptotic variance of the FDP is influenced by different dependence structures. Based on the insights gained from this study, we recommend that in multiple testing procedures utilizing FDP, reporting both the mean and variance estimates of FDP can provide a more comprehensive assessment of the study's outcomes.


Asunto(s)
Incertidumbre , Distribución Normal
4.
Environ Res ; 239(Pt 1): 117227, 2023 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-37778609

RESUMEN

Excessive phosphate and tetracycline (TC) contaminants pose a serious risk to human health and the ecological environment. As such exploring the simultaneous adsorption of phosphate and TC is garnering increasing attention. In this study, an efficient lanthanum ferrate magnetic biochar (FLBC) was synthesised from crab shells using an ultrasound-assisted sol-gel method to study its performance and mechanisms for phosphate and TC adsorption in aqueous solutions in mono/bis systems. According to the Langmuir model, the developed exhibited a maximum adsorption capacity of 65.62 mg/g for phosphate and 234.1 mg/g for TC (pH:7.0 ± 0.1, and 25 °C). Further, it exhibited high resistance to interference and pH suitability. In practical swine wastewater applications, whereby the concentrations of phosphate and TC are 37 and 19.97 mg/L, respectively, the proposed material demonstrated excellent performance. In addition, electrostatic adsorption, chemical precipitation and ligand exchange were noted to be the main mechanisms for phosphate adsorption by FLBC, whereas hydrogen bonding and π-π interaction were the main adsorption mechanisms for TC adsorption. Therefore, this study successfully prepared a novel and efficient adsorbent for phosphate and TC.


Asunto(s)
Fosfatos , Pirólisis , Humanos , Animales , Porcinos , Tetraciclina , Antibacterianos , Fenómenos Magnéticos
5.
Sensors (Basel) ; 23(16)2023 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-37631818

RESUMEN

Social media is a real-time social sensor to sense and collect diverse information, which can be combined with sentiment analysis to help IoT sensors provide user-demanded favorable data in smart systems. In the case of insufficient data labels, cross-domain sentiment analysis aims to transfer knowledge from the source domain with rich labels to the target domain that lacks labels. Most domain adaptation sentiment analysis methods achieve transfer learning by reducing the domain differences between the source and target domains, but little attention is paid to the negative transfer problem caused by invalid source domains. To address these problems, this paper proposes a cross-domain sentiment analysis method based on feature projection and multi-source attention (FPMA), which not only alleviates the effect of negative transfer through a multi-source selection strategy but also improves the classification performance in terms of feature representation. Specifically, two feature extractors and a domain discriminator are employed to extract shared and private features through adversarial training. The extracted features are optimized by orthogonal projection to help train the classification in multi-source domains. Finally, each text in the target domain is fed into the trained module. The sentiment tendency is predicted in the weighted form of the attention mechanism based on the classification results from the multi-source domains. The experimental results on two commonly used datasets showed that FPMA outperformed baseline models.

6.
J Med Virol ; 94(11): 5492-5506, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-35879101

RESUMEN

During the long coevolution of human cytomegalovirus (HCMV) and humans, the host has formed a defense system of multiple layers to eradicate the invader, and the virus has developed various strategies to evade host surveillance programs. The intrinsic immunity primarily orchestrated by promyelocytic leukemia (PML) nuclear bodies (PML-NBs) represents the first line of defense against HCMV infection. Here, we demonstrate that microrchidia family CW-type zinc finger 3 (MORC3), a PML-NBs component, is a restriction factor targeting HCMV infection. We show that depletion of MORC3 through knockdown by RNA interference or knockout by CRISPR-Cas9 augmented immediate-early protein 1 (IE1) gene expression and subsequent viral replication, and overexpressing MORC3 inhibited HCMV replication by suppressing IE1 gene expression. To relief the restriction, HCMV induces transient reduction of MORC3 protein level via the ubiquitin-proteasome pathway during the immediate-early to early stage. However, MORC3 transcription is upregulated, and the protein level recovers in the late stages. Further analyses with temporal-controlled MORC3 expression and the major immediate-early promoter (MIEP)-based reporters show that MORC3 suppresses MIEP activity and consequent IE1 expression with the assistance of PML. Taken together, our data reveal that HCMV enforces temporary loss of MORC3 to evade its repression against the initiation of immediate-early gene expression.


Asunto(s)
Infecciones por Citomegalovirus , Proteínas Inmediatas-Precoces , Adenosina Trifosfatasas/metabolismo , Citomegalovirus/genética , Proteínas de Unión al ADN/metabolismo , Humanos , Proteínas Inmediatas-Precoces/genética , Proteínas Inmediatas-Precoces/metabolismo , Proteína de la Leucemia Promielocítica/genética , Proteína de la Leucemia Promielocítica/metabolismo , Replicación Viral
7.
World J Microbiol Biotechnol ; 38(3): 37, 2022 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-35018528

RESUMEN

Thiamphenicol (TAP) is an amphenicol antibiotic, which has a broad-spectrum inhibitory effect on both gram-positive and gram-negative bacteria. Since it is widely used in animals and aquaculture, its residues in environment may bring potential risk for human health and ecosystems. While TAP can be removed through conventional physical or chemical methods, its bioremediation using microorganisms is less studied. Here, we report the removal of TAP by a bacterial strain, Aeromonas hydrophila HS01, which can remove more than 90.0% of TAP in a living cell-dependent manner. Our results indicated that its removal efficiency can be greatly affected by the growth condition. Proteomics studies revealed a number of differentially expressed proteins of HS01 in the presence of TAP, which may play critical roles in the transportation and degradation of TAP. All these results indicate bacterial strain A. hydrophila HS01 is a new microbial resource for efficiently removing TAP, and may shed new insights in developing bioremediation approaches for TAP pollution.


Asunto(s)
Aeromonas hydrophila/metabolismo , Antibacterianos/metabolismo , Tianfenicol/metabolismo , Animales , Antibacterianos/farmacología , Acuicultura , Biodegradación Ambiental , Ecosistema , Bacterias Gramnegativas , Bacterias Grampositivas , Humanos , Proteómica/métodos , Tianfenicol/farmacología
8.
Curr Genomics ; 22(7): 485-495, 2021 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-35386433

RESUMEN

Circular RNA (circRNA) is a non-coding molecule produced through alternative splicing of one or more exons of a gene in the presence of an RNA-induced silencing complex (RISC). Its formation depends on complementary intron sequences on both sides of the circularized sequence. CircRNA functions as a sponge for miRNA, playing the role of the transcriptional regulator or potential biomarker. It has an impact on fetal growth and on synaptic facilitation in the brain. In this review, we illustrate biogenesis mechanisms, characteristics, and functions of cirRNAs. We also summarize methods using sequence feature and RNA next-generation sequencing data for circRNA prediction. Finally, we discuss the state of the research on circRNA in diseases, which will bring new contributions to future disease treatments.

9.
Biotechnol Lett ; 43(4): 899-907, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33389273

RESUMEN

OBJECTIVE: To develop a new DNA assembly method based on FnCas12a and T5 exonuclease. RESULTS: We developed a method named as FnCas12a and T5 exonuclease (CT5) cloning system. FnCas12a performs site-directed cleavage to the target DNA fragments, and T5 exonuclease generates 20-30 nt single-stranded region at each end of the DNA fragments for homologous recombination-mediated DNA assembly. CT5 was applied to multi-fragment assembly and DNA cloning of large vectors (> 10 kb). The efficiencies were approximately 91.4% and 97%, respectively. In addition, CT5 cloning is also utilized for the "walking" of DNA elements, which enables subtle modification of the relative distances of DNA elements in plasmids. CONCLUSIONS: The CT5 method was a precise and exquisite DNA operating system and provided an ideal platform for the study of gene functions, genetic engineering and synthetic biology.


Asunto(s)
Proteínas Bacterianas/genética , Proteínas Asociadas a CRISPR/genética , Clonación Molecular/métodos , Endodesoxirribonucleasas/genética , Exodesoxirribonucleasas/genética , Proteínas Bacterianas/metabolismo , Proteínas Asociadas a CRISPR/metabolismo , Endodesoxirribonucleasas/metabolismo , Escherichia coli/genética , Escherichia coli/crecimiento & desarrollo , Exodesoxirribonucleasas/metabolismo , Ingeniería Genética , Plásmidos/genética , Recombinación Genética , Biología Sintética
10.
J Sep Sci ; 42(4): 878-887, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30556319

RESUMEN

To enrich carbamate pesticides from complex matrices, an adsorbent based on poly (vinylboronic anhydride pyridine complex-co-ethylenedimethacrylate) monolith was fabricated and utilized as the extraction phase of multiple monolithic fiber solid-phase microextraction. Due to the abundant boron atoms in the monolith, the B-N coordination interaction between adsorbent and analytes play a key role in the efficient extraction of analytes. Under the optimized conditions, the monolithic fibers were combined with high-performance liquid chromatography for the quantify trace levels of carbamate pesticides in environmental water and orange juice samples. For water sample, the limit of detection and limit of quantification were in the range of 0.017-0.29 and 0.057-0.96 µg/L, respectively. The related values in orange juice samples were 0.038-0.39 and 0.12-1.36 µg/kg, respectively. Besides, the proposed method also exhibits wide linearity, satisfactory coefficients of determination, and good precision. The introduced approach was successfully applied to determine trace target analytes in real-life samples. The spiked recoveries with different fortified concentrations were in the range of 80.4-117% for water samples and 83.7-119% for fruit juice samples. The relative standard deviations were below 10%. The results evidence that the suggested method was convenient, reliable, and eco-friendly for the monitoring of trace levels of carbamate pesticides in complex samples such as waters and juices.


Asunto(s)
Boro/química , Carbamatos/análisis , Jugos de Frutas y Vegetales/análisis , Residuos de Plaguicidas/análisis , Microextracción en Fase Sólida , Contaminación Química del Agua/análisis , Adsorción , Tamaño de la Partícula , Propiedades de Superficie
11.
J Biol Chem ; 292(50): 20707-20719, 2017 12 15.
Artículo en Inglés | MEDLINE | ID: mdl-29038295

RESUMEN

An endoplasmic reticulum (ER) retention sequence (ERS) is a characteristic short sequence that mediates protein retention in the ER of eukaryotic cells. However, little is known about the detailed molecular mechanism involved in ERS-mediated protein ER retention. Using a new surface display-based fluorescence technique that effectively quantifies ERS-promoted protein ER retention within Saccharomyces cerevisiae cells, we performed comprehensive ERS analyses. We found that the length, type of amino acid residue, and additional residues at positions -5 and -6 of the C-terminal HDEL motif all determined the retention of ERS in the yeast ER. Moreover, the biochemical results guided by structure simulation revealed that aromatic residues (Phe-54, Trp-56, and other aromatic residues facing the ER lumen) in both the ERS (at positions -6 and -4) and its receptor, Erd2, jointly determined their interaction with each other. Our studies also revealed that this aromatic residue interaction might lead to the discriminative recognition of HDEL or KDEL as ERS in yeast or human cells, respectively. Our findings expand the understanding of ERS-mediated residence of proteins in the ER and may guide future research into protein folding, modification, and translocation affected by ER retention.


Asunto(s)
Aminoácidos Aromáticos/química , Retículo Endoplásmico/metabolismo , Modelos Moleculares , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/metabolismo , Secuencias de Aminoácidos , Sustitución de Aminoácidos , Línea Celular , Retículo Endoplásmico/enzimología , Humanos , Proteínas de la Membrana/química , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismo , Peso Molecular , Mutagénesis Sitio-Dirigida , Mutación , Conformación Proteica , Ingeniería de Proteínas , Dominios y Motivos de Interacción de Proteínas , Receptores Citoplasmáticos y Nucleares/química , Receptores Citoplasmáticos y Nucleares/genética , Receptores Citoplasmáticos y Nucleares/metabolismo , Receptores de Péptidos/química , Receptores de Péptidos/genética , Receptores de Péptidos/metabolismo , Proteínas Recombinantes de Fusión/química , Proteínas Recombinantes de Fusión/metabolismo , Saccharomyces cerevisiae/citología , Saccharomyces cerevisiae/enzimología , Proteínas de Saccharomyces cerevisiae/química , Proteínas de Saccharomyces cerevisiae/genética , Especificidad de la Especie , Técnicas del Sistema de Dos Híbridos
13.
J Sep Sci ; 40(21): 4203-4212, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28869361

RESUMEN

A simple and sensitive method for the simultaneous extraction and determination of six aminoglycosides in honey and milk samples was developed using multiple monolithic fiber solid-phase microextraction and liquid chromatography with tandem mass spectrometry. The multiple monolithic fibers based on poly(methacrylic acid-co-ethylenedimethacrylate) monolith as the extraction medium was used to concentrate target analytes. Because there were abundant carboxyl groups in the monolith, the monolithic fibers could extract aminoglycosides effectively through cation-exchange and hydrophobic interactions. To obtain optimum extraction performance, several extraction parameters including desorption solvent, adsorption and desorption time, pH value and ionic strength in sample matrix, were investigated in detail. Under the optimized extraction conditions, the limits of detection of the proposed method were 0.10-0.30 and 0.23-0.59 µg/kg for honey and milk samples, respectively. Satisfactory linearity was achieved for analytes with the coefficients of determination above 0.99. At the same time, the developed method showed acceptable method repeatability and reproducibility. Finally, the proposed method was successfully applied to the determination of aminoglycosides in real honey and milk samples. Recoveries obtained for the determination of six target analytes in spiking samples ranged from 67.9 to 110%, and the relative standard deviations were in the range of 1.2-11%.


Asunto(s)
Aminoglicósidos/aislamiento & purificación , Miel/análisis , Leche/química , Animales , Cromatografía Liquida , Reproducibilidad de los Resultados , Espectrometría de Masas en Tándem
14.
J Sep Sci ; 40(3): 733-743, 2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-27888568

RESUMEN

A new multiple monolithic fiber solid-phase microextraction using a polydopamine-based monolith as the extraction medium is proposed. The monolith was synthesized by facile in situ copolymerization of N-methacryldopamine and dual cross-linkers (divinylbenzene/ethylenedimethacrylate) in the presence of N,N-dimethylformamide. The effect of the contents of N-methacryldopamine and porogen in the polymerization mixture on the extraction performance was investigated thoroughly. A series of characterization studies was performed to validate the structure and properties of the monolith. The prepared multiple monolithic fibers were used for the extraction of triazine herbicides in environmental water samples. After the optimization of the extraction parameters, a convenient, sensitive, cost-effective, and environmentally friendly method for the determination of trace triazine herbicides in water samples was developed by coupling multiple monolithic fibers solid-phase microextraction with high-performance liquid chromatography and diode array detection. The results indicated that the limits of detection and quantification for the target compounds were 0.031-0.14 and 0.10-0.45 µg/L, respectively. Good precision and reproducibility were obtained with the relative standard deviations below 10%. The developed method was applied to the analysis of the triazine herbicides in different water samples (lake, river, and farmland waters). The recoveries of the method were in the range between 79.6 and 117%.

15.
Anal Chem ; 88(3): 1900-7, 2016 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-26742590

RESUMEN

Monolith-based in-tube solid phase microextraction (MB/IT-SPME) has received wide attention because of miniaturization, automation, expected loading capacity, and environmental friendliness. However, the unsatisfactory extraction efficiency becomes the main disadvantage of MB/IT-SPME. To overcome this circumstance, magnetism-enhanced MB/IT-SPME (ME-MB/IT-SPME) was developed in the present work, taking advantage of magnetic microfluidic principles. First, modified Fe3O4 nanoparticles were mixed with polymerization solution and in situ polymerized in the capillary to obtain a magnetic monolith extraction phase. After that, the monolithic capillary column was placed inside a magnetic coil that allowed the exertion of a variable magnetic field. The effects of intensity of magnetic field, adsorption and desorption flow rate, volume of sample, and desorption solvent on the performance of ME-MB/IT-SPME were investigated in detail. The analysis of six steroid hormones in water samples by the combination of ME-MB/IT-SPME with high-performance liquid chromatography with diode array detection was selected as a paradigm for the practical evaluation of ME-MB/IT-SPME. The application of a controlled magnetic field resulted in an obvious increase of extraction efficiencies of the target analytes between 70% and 100%. The present work demonstrated that application of different magnetic forces in adsorption and desorption steps can effectively enhance extraction efficiency of MB/IT-SPME systems.

16.
J Cardiovasc Pharmacol ; 68(4): 257-264, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-27195652

RESUMEN

Ginsenoside Rg1 (Rg1), a protopanaxadiol saponin extracted from Chinese medicine Panax ginseng C.A. Meyer, has been demonstrated to inhibit the cardiac hypertrophy. However, the molecular mechanisms underlying the inhibition remain poorly understood. Activation of nuclear factor-kappa B (NF-κB) mediated by tumor necrosis factor α (TNF-α) gets involved in the cardiac hypertrophy. This study is designed to investigate the effects and the potential mechanism of Rg1 on the abdominal aorta coarctation (AAC)-induced cardiac hypertrophy with focus on TNF-α/NF-κB signaling pathway. The results showed that oral administration of Rg1 dose-dependently improved the pathological changes, decreased the ratios of left ventricular weight/body weight (LVW/BW) and heart weight/BW (HW/BW), corrected the dysfunction of the cardiac hemodynamics by decreasing the left ventricular systolic pressure and left ventricular end-diastolic pressure and increasing the maximal rate of left ventricular systolic and diastolic pressure (±dp/dtmax) compared with the AAC alone. Rg1 also downregulated the atrial natriuretic peptide mRNA expression and decreased the mRNA and protein expression of TNF-α in the heart tissue of rats compared with the AAC alone. In addition, Rg1 and BAY, the specific inhibitor of NF-κB, decreased the protein content and downregulated the mRNA expression of atrial natriuretic peptide in neonatal rat ventricular myocytes treated with TNF-α. Furthermore, Rg1 increased the protein expression of p65, the subunit of NF-κB, in cytoplasm and decreased the expression p65 in nucleus of the heart tissue of rats undergoing the AAC and of neonatal rat ventricular myocytes treated with TNF-α. The results suggested that Rg1 attenuates the AAC-induced cardiac hypertrophy through inhibition of TNF-α/NF-κB signaling pathway.


Asunto(s)
Aorta Abdominal/efectos de los fármacos , Coartación Aórtica/tratamiento farmacológico , Cardiomegalia/prevención & control , Ginsenósidos/farmacología , FN-kappa B/antagonistas & inhibidores , Factor de Necrosis Tumoral alfa/antagonistas & inhibidores , Animales , Aorta Abdominal/metabolismo , Coartación Aórtica/metabolismo , Cardiomegalia/metabolismo , Células Cultivadas , Ginsenósidos/uso terapéutico , Masculino , FN-kappa B/metabolismo , Distribución Aleatoria , Ratas , Ratas Sprague-Dawley , Factor de Necrosis Tumoral alfa/metabolismo
17.
Can J Physiol Pharmacol ; 94(11): 1132-1140, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27453997

RESUMEN

Endothelial cell injury caused by reactive oxygen species (ROS) plays a critical role in the pathogenesis of cardiovascular disorders. Astragaloside IV (AsIV) possesses potent antioxidant properties against oxidative stress through undefined mechanism(s). We sought to investigate whether AsIV protects human umbilical vein endothelial cells (HUVECs) from hydrogen peroxide (H2O2) induced oxidative stress focusing on eNOS uncoupling and the NADPH oxidase - ROS - NF-κB pathway. Compared with HUVECs incubated with H2O2 alone, pretreatment with AsIV significantly increased the viability of HUVECs, which was accompanied with apparent increase in nitric oxide (NO) production and decrease in intracellular superoxide anion production. Furthermore, pretreatment with AsIV increased endothelial nitric oxide synthase (eNOS) dimer/monomer ratio and its critical cofactor tetrahydrobiopterin (BH4) content, decreased Nox4 protein expression (the most abundant Nox isoform in HUVECs), inhibited translocation of NF-κB p65 subunit into nuclear fraction while enhanced the protein expression of IκB-α (the inhibitor of NF-κB p65), reduced the levels of IL-1ß, IL-6, and TNF-α in HUVECs medium, and decreased iNOS protein expression. These results suggest that AsIV may protect HUVECs from H2O2-induced oxidative stress via inhibiting NADPH oxidase - ROS - NF-κB pathway and eNOS uncoupling.

18.
J Sep Sci ; 39(10): 1908-18, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26990593

RESUMEN

In this study, a new stir cake sorptive extraction using a boron-rich monolith as the adsorbent was prepared by the in situ copolymerization of vinylboronic anhydride pyridine complex and divinylbenzene. The effect of preparation parameters, including the ratio of vinylboronic anhydride pyridine complex and divinylbenzene, monomer mixture, and porogen solvent, on extraction performance was investigated thoroughly. The physicochemical properties of the adsorbent were characterized by infrared spectroscopy, scanning electron microscopy, and mercury intrusion porosimetry. Several conditions affecting the extraction efficiency were investigated in detail. Under the optimized conditions, a convenient and sensitive method for the determination of trace fluoroquinolones residues in water and milk samples was established by coupling stir cake sorptive extraction with high-performance liquid chromatography and diode array detection. The limits of detection for the target compounds were 0.10-0.26 and 0.11-0.22 µg/L for water and milk samples, respectively. In addition, the developed method showed good linearity, repeatability, and precision. Finally, the proposed method was successfully applied for the detection of trace fluoroquinolones residues in environmental water and milk samples. Satisfactory recoveries were obtained for the determination of fluoroquinolones in spiking samples that ranged from 68.8 to 120%, with relative standard deviations below 10% in all cases.


Asunto(s)
Boro/química , Fluoroquinolonas/análisis , Extracción Líquido-Líquido , Leche/química , Contaminantes Químicos del Agua/química , Adsorción , Animales , Cromatografía Líquida de Alta Presión
19.
J Sep Sci ; 39(3): 566-75, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26608868

RESUMEN

The development of a simple and sensitive analytical approach that combines multiple monolithic fiber solid-phase microextraction with liquid desorption followed by high-performance liquid chromatography with diode array detection is proposed for the determination of trace levels of seven steroid sex hormones (estriol, 17ß-estradiol, testosterone, ethinylestradiol, estrone, progesterone and mestranol) in water and urine matrices. To extract the target analytes effectively, multiple monolithic fiber solid-phase microextraction based on a polymeric ionic liquid was used to concentrate hormones. Several key extraction parameters including desorption solvent, extraction and desorption time, pH value and ionic strength in sample matrix were investigated in detail. Under the optimal experimental conditions, the limits of detection were found to be in the range of 0.027-0.12 µg/L. The linear range was 0.10-200 µg/L for 17ß-estradiol, 0.25-200 µg/L estriol, ethinylestradiol and estrone, and 0.50-200 µg/L for the other hormones. Satisfactory linearities were achieved for analytes with the correlation coefficients above 0.99. Acceptable method reproducibility was achieved by evaluating the repeatability and intermediate precision with relative standard deviations of both less than 8%. The enrichment factors ranged from 54- to 74-fold. Finally, the proposed method was successfully applied to the analysis of steroid sex hormones in environmental water samples and human urines with spiking recoveries ranged from 75.6 to 116%.


Asunto(s)
Hormonas Esteroides Gonadales/análisis , Líquidos Iónicos/química , Microextracción en Fase Sólida/métodos , Contaminantes del Agua/análisis , Cromatografía Líquida de Alta Presión , Hormonas Esteroides Gonadales/orina , Concentración de Iones de Hidrógeno , Límite de Detección , Concentración Osmolar
20.
Pol J Microbiol ; 65(1): 5-12, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27281989

RESUMEN

Yersinia species are bacterial pathogens that can cause plague and intestinal diseases after invading into human cells through the Three Secretion System (TTSS). The effect of pathogenesis is mediated by Yersinia outer proteins (Yop) and manifested as down-regulation of the cytokine genes expression by inhibiting nuclear factor-κ-gene binding (NF-κB) and mitogen-activated protein kinase (MAPK) pathways. In addition, its pathogenesis can also manipulate the disorder of host innate immune system and cell death such as apoptosis, pyroptosis, and autophagy. Among the Yersinia effector proteins, YopB and YopD assist the injection of other virulence effectors into the host cytoplasm, while YopE, YopH, YopJ, YopO, and YopT target on disrupting host cell signaling pathways in the host cytosols. Many efforts have been applied to reveal that intracellular proteins such as Rho-GTPase, and transmembrane receptors such as Toll-like receptors (TLRs) both play critical roles in Yersinia pathogenesis, establishing a connection between the pathogenic process and the signaling response. This review will mainly focus on how the effector proteins of Yersinia modulate the intrinsic signals in host cells and disturb the innate immunity of hosts through TTSS.


Asunto(s)
Proteínas Bacterianas/metabolismo , Regulación Bacteriana de la Expresión Génica/fisiología , Yersiniosis/microbiología , Yersinia/patogenicidad , Proteínas Bacterianas/genética , Humanos , Virulencia
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