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1.
Phys Rev Lett ; 123(8): 080401, 2019 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-31491194

RESUMO

We report an experiment to test quantum interference, entanglement, and nonlocality using two dissimilar photon sources, the Sun and a semiconductor quantum dot on the Earth, which are separated by ∼150 million kilometers. By making the otherwise vastly distinct photons indistinguishable in all degrees of freedom, we observe time-resolved two-photon quantum interference with a raw visibility of 0.796(17), well above the 0.5 classical limit, providing unambiguous evidence of the quantum nature of thermal light. Further, using the photons with no common history, we demonstrate postselected two-photon entanglement with a state fidelity of 0.826(24) and a violation of Bell inequality by 2.20(6). The experiment can be further extended to a larger scale using photons from distant stars and open a new route to quantum optics experiments at an astronomical scale.

2.
Bone Joint J ; 101-B(9): 1160-1167, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31474136

RESUMO

AIMS: The aim of this study was to clarify the factors that predict the development of avascular necrosis (AVN) of the femoral head in children with a fracture of the femoral neck. PATIENTS AND METHODS: We retrospectively reviewed 239 children with a mean age of 10.0 years (sd 3.9) who underwent surgical treatment for a femoral neck fracture. Risk factors were recorded, including age, sex, laterality, mechanism of injury, initial displacement, the type of fracture, the time to reduction, and the method and quality of reduction. AVN of the femoral head was assessed on radiographs. Logistic regression analysis was used to evaluate the independent risk factors for AVN. Chi-squared tests and Student's t-tests were used for subgroup analyses to determine the risk factors for AVN. RESULTS: We found that age (p = 0.006) and initial displacement (p = 0.001) were significant independent risk factors. Receiver operating characteristic (ROC) curve analysis indicated that 12 years of age was the cut-off for increasing the rate of AVN. Severe initial displacement (p = 0.021) and poor quality of reduction (p = 0.022) significantly increased the rate of AVN in patients aged 12 years or greater, while in those aged less than 12 years, the rate of AVN significantly increased only with initial displacement (p = 0.048). A poor reduction significantly increased the rate of AVN in patients treated by closed reduction (p = 0.026); screw and plate fixation was preferable to cannulated screw or Kirschner wire (K-wire) fixation for decreasing the rate of AVN in patients treated by open reduction (p = 0.034). CONCLUSION: The rate of AVN increases with age, especially in patients aged 12 years or greater, and with the severity of displacement. In patients treated by closed reduction, anatomical reduction helps to decrease the rate of AVN, while in those treated by open reduction, screw and plate fixation was preferable to fixation using cannulated screws or K-wires. Cite this article: Bone Joint J 2019;101-B:1160-1167.

3.
Chin Med J (Engl) ; 2019 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-31490264

RESUMO

BACKGROUND: MicroRNAs (miRNAs) have played important roles in the regulation of gene expression in many cancers, but their roles in esophageal squamous cell carcinoma (ESCC) are still unclear. The aim of this study was to determine the potential ESCC-specific key miRNAs from a large sample dataset in The Cancer Genome Atlas (TCGA). METHODS: Integrative bioinformatics analysis was used to identify key ESCC-specific miRNAs related to the ESCC patients' tumor histological grade and lymphatic metastasis from TCGA. Next, these key miRNA potential gene regulatory functions and relationships with ESCC patients' clinical characteristics and overall survival were analyzed. Finally, three key miRNAs were selected randomly and quantificational real-time polymerase chain reaction (qRT-PCR) was used to validate in 51 newly diagnosed ESCC patients' tissues samples (collected from Nov. 2017 to Feb. 2019, in Wuwei, China) whether the bioinformatics analyses results were reliable and valid. Two-tailed Student's t test, Pearson chi-squared test and Kaplan-Meier survival analysis were used in this study. RESULTS: Thirty-five ESCC-specific miRNAs from TCGA database were investigated (fold-change > 2.0, P < 0.05), and 28 participated in the miRNAs-mRNAs co-expression network construction, while 17 were related with ESCC patients' tumor histological grade, TNM stage, and lymphatic metastasis (P < 0.05). Meanwhile, there were six miRNAs (including miR-200b-3p, miR-31-5p, miR-15b-5p, miR-141-3p, miR-135b-5p, and miR-195-5p) those were correlated with overall survival of ESCC patient (log-rank, P < 0.05). MiR-135b-5p, miR-15b-5p, and miR-195-5p were selected for verification of the expression levels in 51 ESCC patients' tissue samples by using qRT-PCR. We found that the fold-changes between qRT-PCR and TCGA were completely consistent. The results also suggested that miR-135b-5p, miR-15b-5p, and miR-195-5p were significantly correlated with tumor differentiation degrees (P < 0.05), miR-195-5p was significantly correlated with tumor TNM stage (P < 0.05), and miR-135b-5p was significantly correlated with lymph-node metastasis (P < 0.05). MiR-135b-5p, miR-15b-5p, and miR-195-5p expression levels, ESCC patient clinical features association analysis results and the aforementioned TCGA bioinformatics analyses were similar. CONCLUSION: This study identified key ESCC-related miRNAs. The key miRNAs are worthy of further investigation as potential novel biomarkers for diagnosis, classification, and prognosis of ESCC.

4.
Cancer Res ; 2019 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-31481501

RESUMO

Obese women have higher risk of bearing breast tumors which are highly aggressive and resistant to therapies. Tumor-promoting effects of obesity occur locally via adipose inflammation and related alterations to the extracellular matrix (ECM) as well as systemically via circulating metabolic mediators (e.g. free fatty acids, FFA) associated with excess adiposity and implicated in toll-like receptor-mediated activation of macrophages - key cellular players in obesity-related cancer progression. While the contribution of macrophages to pro-neoplastic effects of obesity is well-documented, the role of ECM components and their enzymatic degradation is less appreciated. We show that heparanase, the sole mammalian endoglucuronidase that cleaves heparan sulfate in ECM, is preferentially expressed in clinical/experimental obesity-associated breast tumors. Heparanase deficiency abolished obesity-accelerated tumor progression in vivo. Heparanase orchestrated a complex molecular program which occurred concurrently in adipose and tumor tissue, and sustained the cancer-promoting action of obesity. Heparanase was required for adipose tissue macrophages (atM) to produce inflammatory mediators responsible for local induction of aromatase, a rate-limiting enzyme in estrogen biosynthesis. Estrogen upregulated heparanase in hormone-responsive breast tumors. In subsequent stages, elevated levels of heparanase induced acquisition of pro-cancerous phenotype by tumor-associated macrophages (TAM), resulting in activation of tumor-promoting signaling and acceleration of breast tumor growth under obese conditions. As techniques to screen for heparanase expression in tumors become available, these findings provide rational and a mechanistic basis for designing anti-heparanase approaches to uncouple obesity and breast cancer in a rapidly growing population of obese patients.

5.
Food Funct ; 2019 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-31482168

RESUMO

Lemon is a healthy fruit with high medicinal value. This study found that lemon water soluble extract (LET) can reduce uric acid levels in mice with potassium oxonate induced hyperuricemia. Histopathological analysis suggested that LET caused little damage to the kidneys of mice. It affected mABCG2 and mGLUT9 mRNA expression only in hyperuricemic mice, but not in healthy mice. Our further results show that potassium citrate, rather than citric acid, is the main ingredient in LET with a hypouricemic effect. This study also indicates that lemon does have unique medicinal value for the treatment of hyperuricemia, and that potassium citrate has the potential to be developed as a drug for hyperuricemia. Lowering uric acid through LET and potassium citrate may directly promote the degradation of excessive uric acid in patients with hyperuricemia.

7.
J Chromatogr A ; : 460509, 2019 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-31515076

RESUMO

A simple and efficient sample preparation method to extract four bioactive compounds (echinacoside, specnuezhenide, oleuropein and nuezhenoside G13) from Ligustri Lucidi Fructus was established by vortex-forced matrix solid phase dispersion (VFMSPD) method. Chitosan solution was applied as green eluent in this procedure and Celite AZO was employed as dispersant. High performance liquid chromatography (HPLC) equipped with ultraviolet (UV) detector was used to analyze the target analytes. The best result of the investigation was obtained with Celite AZO as dispersant, sample/ dispersant ratio as 1:1, grinding for 2 min, 1 mL high-viscosity chitosan solution (0.5 mg mL-1) used as the elution reagent and vortex mixing for 1.5 min. The method exhibit a good linearity for the analytes (r2 > 0.999). The absolute recoveries of the four target compounds in Ligustri Lucidi Fructus ranged from 90.7% to 98.8% and the relative recoveries of the target compounds ranged from 99.2% to 102% (RSD ≤ 3.4%), which were obtained by the final optimization method. Consequently, the newly developed chitosan solution-based vortex-forced matrix solid phase dispersion (MSPD) combined with HPLC could be efficiently applied to extract and analyze the target compounds in Ligustri Lucidi Fructus samples.

8.
Virol J ; 16(1): 114, 2019 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-31511025

RESUMO

BACKGROUND: Human papillomavirus type-6 (HPV6) is the major etiological agent of anogenital warts both men and women. The present study aimed to characterize the genetic diversity among HPV6 in Southwest China, and to investigate the origin of, selective pressure experienced by, and impact of the resultantly identified genetic variants on the HPV6 secondary structure. METHODS: Phylogenetic trees were constructed by Maximum-likelihood and the Kimura 2-parameters methods by Molecular Evolutionary Genetics Analysis version 6.0. The diversity of secondary structure was analyzed by PSIPred software. The selection pressures acting on the E6/E7 genes were estimated by Phylogenetic Analyses by Maximum Likelihood version 4.8 software. RESULTS: HPV6 was the most prevalent low risk HPV type in southwest China. In total, 143 E6 and E7 gene sequences of HPV6 isolated from patients were sequenced and compared to GenBank HPV6 reference sequence X00203. The results of these analyses revealed that both the HPV6 E6 and E7 were highly conserved within the analyzed patient samples, and comprised only 3 types of variant sequence, respectively. Furthermore, the analysis of HPV6 E6 and E7 sequences revealed seven/five single-nucleotide mutations, two/four and five/one of which were non-synonymous and synonymous, respectively. The phylogenetic analyses of the E6 and E7 sequences indicated that they belonged to sub-lineage A1 and sub-lineage B1, whereas the selective pressure analyses showed that only the E7 mutation sites 4R, 34E, and 52F were positive selection. CONCLUSIONS: HPV6 (detection rate = 13.10%) was very prevalent in southwest China, both the HPV6 E6 and E7 sequences were highly conserved within the analyzed patient samples in southwest China, indicating that the low risk HPV6 can adapt to the environment well without much evolution.

9.
Biosens Bioelectron ; 143: 111599, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31476600

RESUMO

The reliable quantitative analysis of tumor biomarkers in circulating blood is crucial for cancer early screening, therapy monitoring and prognostic prediction. Herein, a novel biosensor combing surface-enhanced Raman spectroscopy (SERS) and surface molecularly imprinted polymer (SMIP) technology was developed for quantitative detection of carcinoembryonic antigen (CEA) that is closely related to several common cancers. Owing to the use of SMIP, recognition sites with high affinity to the target of interest can be well imprinted on the surface of SERS substrate, leading to a more stable and specific capture ability. In addition, two layers of core-shell nanoparticles were integrated to this SERS substrate to form highly efficient electromagnetic enhancement for SERS measurement via the generation of lots of "hot spot". Besides, a unique Raman reporter (CC) with silent Raman signals at 2024 cm-1 was capsulated in the nanoparticles to avoid the optical noises originating from endogenous molecules at fingerprint region (300-1800 cm-1). Meanwhile, we employed an internal standard molecular (CN) to real time correct the fluctuating signals of Raman reporter when performing the quantitative analysis. Due to these features, a limit of detection (LOD) of 0.064 pg mL-1 with the detection range of 0.1 pg mL-1 - 10 µg mL-1 can be achieved by this assay. Excitingly, this technology even showed wonderful performances for CEA detection in real blood from cancer patients, demonstrating great potential for biomarker-based cancer screening.

10.
Aging (Albany NY) ; 112019 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-31503544

RESUMO

Cardiac aging is majorly characterized by increased diastolic dysfunction, lipid accumulation, oxidative stress, and contractility debility. The Sir2/Sirt1 gene overexpression delays cell aging and reduces obesity and oxidative stress. Exercise improves heart function and delays heart aging. However, it remains unclear whether exercise delaying heart aging is related to cardiac Sir2/Sirt1-related pathways. In this study, cardiac dSir2 overexpression or knockdown was regulated using the UAS/hand-Gal4 system in Drosophila. Flies underwent exercise interventions from 4 weeks to 5 weeks old. Results showed that either cardiac dSir2 overexpression or exercise remarkably increased the cardiac period, systolic interval, diastolic interval, fractional shortening, SOD activity, dSIR2 protein, Foxo, dSir2, Nmnat, and bmm expression levels in the aging flies; they also notably reduced the cardiac triacylglycerol level, malonaldehyde level, and the diastolic dysfunction index. Either cardiac dSir2 knockdown or aging had almost opposite effects on the heart as those of cardiac dSir2 overexpression. Therefore, we claim that cardiac dSir2 overexpression or knockdown delayed or promoted heart aging by reducing or increasing age-related oxidative stress, lipid accumulation, diastolic dysfunction, and contractility debility. The activation of cardiac dSir2/Foxo/SOD and dSir2/Foxo/bmm pathways may be two important molecular mechanisms through which exercise works against heart aging in Drosophila.

11.
Int J Infect Dis ; 2019 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-31499209

RESUMO

OBJECTIVES: Eight additional provinces in western China reported human infections for the first time during the fifth wave of human H7N9 infections. Our study aimed to analyze the epidemiological and virological characteristics of this outbreak. METHODS: The epidemiological data of H7N9 cases from the newly affected western Chinese provinces were collected and analyzed. Meanwhile, full-length genome sequences of H7N9 virus were downloaded from GenBank and GISAID databases, and phylogenetic, genotyping and genetic analyses were conducted. RESULTS: The peak of human infections in the newly affected western Chinese provinces was delayed by 4 months compared to the eastern China, and both low pathogenic (LP) and highly pathogenic (HP) H7N9 infected cases were found. The LP- and HP-H7N9 virus belonged to 10 different genotypes (including 4 new genotypes), of which G11 and G3 were the dominant genotypes, respectively. Almost all of these viruses originated from eastern and southern China, and were most possibly imported from neighboring provinces. Genetic characteristics of the circulating viruses were similar with the viruses from previously affected provinces during Wave Five. CONCLUSION: A delayed peak of human infections was observed in the newly affected western Chinese provinces, and reassortment has been ongoing since the introduction of H7N9 viruses. Our study highlights the importance of continued surveillance of the circulation and evolution of H7N9 virus in western China.

12.
Nat Plants ; 2019 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-31501530

RESUMO

Coumarins, also known as 1,2-benzopyrones, comprise a large class of secondary metabolites that are ubiquitously found throughout the plant kingdom. In many plant species, coumarins are particularly important for iron acquisition and plant defence. Here, we show that COUMARIN SYNTHASE (COSY) is a key enzyme in the biosynthesis of coumarins. Arabidopsis thaliana cosy mutants have strongly reduced levels of coumarin and accumulate o-hydroxyphenylpropanoids instead. Accordingly, cosy mutants have reduced iron content and show growth defects when grown under conditions in which there is a limited availability of iron. Recombinant COSY is able to produce umbelliferone, esculetin and scopoletin from their respective o-hydroxycinnamoyl-CoA thioesters by two reaction steps-a trans-cis isomerization followed by a lactonization. This conversion happens partially spontaneously and is catalysed by light, which explains why the need for an enzyme for this conversion has been overlooked. The combined results show that COSY has an essential function in the biosynthesis of coumarins in organs that are shielded from light, such as roots. These findings provide routes to improving coumarin production in crops or by microbial fermentation.

13.
Chem Commun (Camb) ; 2019 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-31475996

RESUMO

A new Lewis acid catalysed formal hetero-[5+2] cycloaddition of 2,3-dihydro-1H-pyrroles to terminal alkynes is described. By employing a FeCl3 and BF3·OEt2 co-catalytic strategy, the ring-opening of 1-tosyl-2,3-dihydro-1H-pyrroles by selective cleavage of the C(sp2)-N bond and subsequent annulation have been achieved to access 1-tosyl-2,3-dihydro-1H-azepines with excellent regioselectivity, offering a new avenue for cycloaddition through the ring-opening of non-strained-ring-based units.

14.
Arch Med Res ; 50(3): 86-90, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31495394

RESUMO

BACKGROUND AND AIMS: The chemokine (C-C motif) Ligand 2 (CCL2)/CCR2 signaling was associated with macrophage accumulation, synovitis and cartilage damage in a mouse osteoarthritis (OA) model. MATERIALS AND METHODS: Here a case-control study in a Chinese Han population was conducted to investigate the possible association between the CCL2 gene polymorphism and risk of OA. DNA was extracted from 367 primary knee OA patients and 303 healthy controls. Then CCL2 gene polymorphisms were determined using a standard polymerase chain reaction restriction fragment length polymorphism. Plasma CCL2 levels were measured by using sandwich enzyme-linked immunosorbent assay (ELISA). RESULTS: It was found the CCL2 gene rs1024611 and rs4586 polymorphisms significantly increased the risk of OA. Stratified analyses showed the risk of OA might be increased by rs1024611 polymorphism in males and non-drinkers, and was increased by rs4586 polymorphism among smokers and drinkers. The CC genotype of rs4586 polymorphism was significantly correlated with the increased CCL2 level compared to TT genotype. CONCLUSIONS: In conclusion, CCL2 gene polymorphisms (rs1024611 and rs4586) confer susceptibility to OA and may be potential markers for early diagnosis of OA.

15.
Molecules ; 24(17)2019 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-31443451

RESUMO

An efficient microwave-assisted extraction (MAE) combined with in-capillary [Fe(ferrozine)3]2+-capillary electrophoresis-Diode Array Detector (in-capillary [Fe(ferrozine)3]2+-CE-DAD) was developed to screen active components with the ability to chelate ferrous ions and determine the total antioxidant activity. The MAE conditions, including methanol concentration, extraction power, extraction time, and the ratio of material to liquid, were optimized by an L9(34) orthogonal experiment. Background buffer, voltage, and cartridge temperature that affect the separation of six compounds were optimized. It was found that rutin and quercetin were the main components chelating ferrous ions in Flos Sophorae Immaturus (Flos Sophorae) by the in-capillary [Fe(ferrozine)3]2+-CE-DAD. The recoveries were ranged from 95.2% to 104%. It was concluded that the MAE combined with in-capillary [Fe(ferrozine)3]2+-CE-DAD method was a simple, reliable, and efficient tool for screening active components from the complex traditional Chinese medicine samples and evaluating their ability to chelate ferrous ions.

16.
Int J Cardiol ; 2019 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-31447229

RESUMO

BACKGROUND: Cardiovascular disease is the leading cause of death in the United States. Consequently, individuals who are genetically predisposed for high risk of cardiovascular disease would benefit most from prevention and early intervention approaches. Among common health risk factors affecting adult populations, we evaluated 23 cardiovascular disease-related traits, including BMI, glucose levels and lipid profiling to determine their associations with low-frequency recurrent copy number variations (CNV) (population frequency < 5%). RESULTS: We examined 10,619 unrelated subjects of European ancestry from the Electronic Medical Records and Genomics (eMERGE) Network who were genotyped with 657,366 markers genome-wide on the Illumina Infinium Quad 660 array. We performed CNV calling based on array marker intensity and evaluated data quality, ancestry stratification, and relatedness to ensure unbiased association discovery. Using a segment-based scoring approach, we assessed the association of all CNVs with each trait. In this large genome-wide analysis of low-frequency CNVs, we observed 11 novel genome-wide significant associations of low-frequency CNVs with major cardiovascular disease traits. CONCLUSION: In one of the largest genome-wide studies for low-frequency recurrent CNVs, we identified 11 loci associated with cardiovascular disease and related traits at the genome-wide significance level that may serve as biomarkers for prevention and early intervention studies in subjects who are at elevated risk. Our study further supports the role of low-frequency recurrent CNVs in the pathogenesis of common complex disease traits.

17.
Sci Rep ; 9(1): 11319, 2019 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-31383880

RESUMO

Dynamic optical imaging (e.g. time delay integration imaging) is troubled by the motion blur fundamentally arising from mismatching between photo-induced charge transfer and optical image movements. Motion aberrations from the forward dynamic imaging link impede the acquiring of high-quality images. Here, we propose a high-resolution dynamic inversion imaging method based on optical flow neural learning networks. Optical flow is reconstructed via a multilayer neural learning network. The optical flow is able to construct the motion spread function that enables computational reconstruction of captured images with a single digital filter. This works construct the complete dynamic imaging link, involving the backward and forward imaging link, and demonstrates the capability of the back-ward imaging by reducing motion aberrations.

18.
J Environ Manage ; 248: 109333, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31398677

RESUMO

While the economy and society of China are developing rapidly, various ecological and environmental problems continue to emerge. The problem of air pollution is becoming an issue of increasing concern. Since 2013, Beijing, Tianjin, and Hebei Provinces have collaborated to control air pollution and have achieved certain success. However, the air pollution problem in the capital, Beijing, remains severe. In this study, a quantitative evaluation and analysis method is established for assessing urban air quality and its influencing factors by developing a driving force model. The model combines multiple regression and principal component analysis to account for social, economic, meteorological, and regional factors. The influencing factors with the highest contributions are regional transmission, energy consumption, and industrial structure. This model is used to project the future trend of the air quality in Beijing based on the evolution of the influencing factors, aimed to provide a theoretical basis for policies improving Beijing's air quality.

19.
Pestic Biochem Physiol ; 159: 68-79, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31400786

RESUMO

Chlorpyrifos is a pesticide frequently detected in food and has been reported to disturb endocrine and gut health, which was regulated by gut microbiota and enteroendocrine cells. In this study, newly weaned (3 week) and adult (8 week) male rats fed a normal- or high- fat diet were chronically exposed to 0.3 mg chlorpyrifos/kg bodyweight/day. The effects of chlorpyrifos exposure on serum hormone levels, proinflammatory cytokines and gut microbiota were evaluated. Chronic exposure to chlorpyrifos significantly decreased the concentrations of luteinizing hormone, follicule stimulating hormone and testosterone, which was found only in the normal-fat diet. The counteracted effect of high-fat diet was also found in gut hormones and proinflammatory cytokines. Significantly higher concentrations of glucagon-like peptide-1, pancreatic polypeptide, peptide tyrosine tyrosine (PYY), ghrelin, gastric inhibitory poly-peptide, IL-6, monocyte chemoattractant protein-1, and TNF-α were found in rats exposed to chlorpyrifos beginning at newly weaned, whereas only the PYY, ghrelin and IL-6 concentrations increased significantly in rats exposed in adulthood. Furthermore, a decrease in epinephrine induced by chlorpyrifos exposure was found in rats exposed to chlorpyrifos beginning at newly weaned, regardless of their diet. Chlorpyrifos-induced disturbances in the microbiome community structure were more apparent in rats fed a high-fat diet and exposed beginning at newly weaned. The affected bacteria included short-chain fatty acid-producing bacteria (Romboutsia, Turicibacter, Clostridium sensu stricto 1, norank_f_Coriobacteriaceae, Faecalibaculum, Parasutterella and norank_f__Erysipelotrichaceae), testosterone-related genus (Turicibacter, Brevibacterium), pathogenic bacteria (Streptococcus), and inflammation-related bacteria (unclassified_f__Ruminococcaceae, Ruminococcaceae_UCG-009, Parasutterella, Oscillibacter), which regulated the endocrine system via the hypothalamic-pituitary-adrenal axis, as well as the immune response and gut barrier. Early exposure accelerated the endocrine-disturbing effect and immune responses of chlorpyrifos, although these effects can be eased or recovered by a high-fat diet. This study helped clarify the relationship between disrupted endocrine function and gut microbiota dysbiosis induced by food contaminants such as pesticides.


Assuntos
Clorpirifos/toxicidade , Dieta Hiperlipídica/efeitos adversos , Microbioma Gastrointestinal/efeitos dos fármacos , Inflamação/induzido quimicamente , RNA Ribossômico 16S/metabolismo , Envelhecimento , Animais , Sistema Hipotálamo-Hipofisário/efeitos dos fármacos , Inflamação/metabolismo , Masculino , Sistema Hipófise-Suprarrenal/efeitos dos fármacos , Ratos
20.
Microbiologyopen ; : e910, 2019 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-31452334

RESUMO

Fibronectin-binding protein A (FnBPA) is a key adhesin of Staphylococcus aureus, and the protein binding to fibrinogen and elastin is mediated by its N-terminal A domain. Thus, FnBPA-A has been considered a potential vaccine candidate, but the relevant epitopes are not fully understood. Here, purified rabbit anti-FnBPA-A antibodies were produced and used to screen for peptides corresponding to or mimicking the epitope of native FnBPA-A protein by using a phage random 12-mer peptide library. After four rounds of panning, 25 randomly selected phage clones were detected by phage-ELISA and competition-inhibition ELISA. Then, eight anti-rFnBPA-A antibody-binding phage clones were selected for sequencing, and six different 12-mer peptides were displayed by these phages. Although these displayed peptides shared no more than three consecutive amino acid residues identical to the sequence of FnBPA-A, they could be recognized by the FnBPA-A-specific antibodies in vitro and could induce specific antibodies against FnBPA-A in vivo, suggesting that these displayed peptides were mimotopes of FnBPA-A. Finally, the protective efficiencies of these mimotopes were investigated by mouse vaccination and challenge experiments. Compared with that of control group mice, the relative percent survival of mice immunized with phage clones displaying a mimotope was 13.33% (C2 or C15), 0% (C8), 6.67% (C10), 26.67% (C19 or 1:2 mixture of C23 and C19), 53.33% (C23), 33.33% (1:1 mixture of C23 and C19), and 66.67% (2:1 mixture of C23 and C19). Overall, five peptides mimicking FnBPA-A protein epitopes were obtained, and a partially protective immunity against S. aureus infection could be stimulated by these mimotope peptides in mice.

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