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1.
J Cell Biochem ; 121(1): 867-875, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31452270

RESUMO

Long noncoding RNAs (lncRNAs) are linked to tumor development and progression. The aim of this study was to determine the prognostic significance and biological role of LINC01116 in head and neck squamous cell carcinoma (HNSCC). We identified 21 aberrantly expressed lncRNAs specific to HNSCC that were common in two microarray datasets. LINC01116 was highly overexpressed in HNSCC tissues and was correlated to shorter overall survival and relapse-free survival duration, as analyzed by the online Gene Expression Profiling Interactive Analysis platform. LINC01116 was also overexpressed in oral squamous cell carcinoma and nasopharyngeal carcinoma tissues, and LINC01116 silencing significantly inhibited the migration and invasion capacities of both cell lines by blocking the epithelial-mesenchymal transition process. In addition, 125 coexpressing genes were identified by circlncRNAnet, and were mainly located on human autosomes and enriched in transforming growth factor-ß signaling pathway. These findings indicate that LINC01116 might be a potential therapeutic target for HNSCC.

2.
Acta Pharm ; 70(1): 35-47, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31677374

RESUMO

Allergic rhinitis (AR) is a common disease that causes severe inflammation and even disabilities. Previous studies have reported baicalein to have an anti-inflammatory effect. However, the pharmacological action of baicalein on anaphylaxis has not been clarified yet. This study assessed the in vivo protective effect of baicalein post-treatment in an ameliorating ovalbumin (OVA)-sensitized AR rat model. Baicalein attenuated histological alterations, aberrant tissue repair and inflammation after OVA-induced AR. Baicalein reduced the frequency of nasal/ear rubs and sneezes in rats, and inhibited generation of several inflammatory cytokines (TNF-α, IL-1ß, and IL-6) in both blood and nasal lavage of rats. Infiltrations of eosinophils, lymphocyte, and neutrophils were decreased in baicalein-administered rats. Furthermore, baicalein inhibited the expression of STAT3 phosphorylation in the nasal mucosa. In summary, baicalein attenuated OVA-induced AR and inflammation, which suggests it as a promising therapeutic agent for the alleviation of AR-associated inflammation and pathology.

3.
Nat Commun ; 10(1): 5181, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31729358

RESUMO

Dry reforming of methane (DRM) is an attractive route to utilize CO2 as a chemical feedstock with which to convert CH4 into valuable syngas and simultaneously mitigate both greenhouse gases. Ni-based DRM catalysts are promising due to their high activity and low cost, but suffer from poor stability due to coke formation which has hindered their commercialization. Herein, we report that atomically dispersed Ni single atoms, stabilized by interaction with Ce-doped hydroxyapatite, are highly active and coke-resistant catalytic sites for DRM. Experimental and computational studies reveal that isolated Ni atoms are intrinsically coke-resistant due to their unique ability to only activate the first C-H bond in CH4, thus avoiding methane deep decomposition into carbon. This discovery offers new opportunities to develop large-scale DRM processes using earth abundant catalysts.

4.
BMC Pediatr ; 19(1): 405, 2019 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-31685004

RESUMO

BACKGROUND: An increasing number of extremely preterm (EP) infants have survived worldwide. However, few data have been reported from China. This study was designed to investigate the short-term outcomes of EP infants at discharge in Guangdong province. METHODS: A total of 2051 EP infants discharged from 26 neonatal intensive care units during 2008-2017 were enrolled. The data from 2008 to 2012 were collected retrospectively, and from 2013 to 2017 were collected prospectively. Their hospitalization records were reviewed. RESULTS: During 2008-2017, the mean gestational age (GA) was 26.68 ± 1.00 weeks and the mean birth weight (BW) was 935 ± 179 g. The overall survival rate at discharge was 52.5%. There were 321 infants (15.7%) died despite active treatment, and 654 infants (31.9%) died after medical care withdrawal. The survival rates increased with advancing GA and BW (p < 0.001). The annual survival rate improved from 36.2% in 2008 to 59.3% in 2017 (p < 0.001). EP infants discharged from hospitals in Guangzhou and Shenzhen cities had a higher survival rate than in others (p < 0.001). The survival rate of EP infants discharged from general hospitals was lower than in specialist hospitals (p < 0.001). The major complications were neonatal respiratory distress syndrome, 88.0% (1804 of 2051), bronchopulmonary dysplasia, 32.3% (374 of 1158), retinopathy of prematurity (any grade), 45.1% (504 of 1117), necrotizing enterocolitis (any stage), 10.1% (160 of 1588), intraventricular hemorrhages (any grade), 37.4% (535 of 1431), and blood culture-positive nosocomial sepsis, 15.7% (250 of 1588). The multivariate logistic regression analysis indicated that improved survival of EP infants was associated with discharged from specialist hospitals, hospitals located in high-level economic development region, increasing gestational age, increasing birth weight, antenatal steroids use and a history of premature rupture of membranes. However, twins or multiple births, Apgar ≤7 at 5 min, cervical incompetence, and decision to withdraw care were associated with decreased survival. CONCLUSIONS: Our study revealed the short-term outcomes of EP infants at discharge in China. The overall survival rate was lower than the developed countries, and medical care withdrawal was a serious problem. Nonetheless, improvements in care and outcomes have been made annually.

5.
Chem Commun (Camb) ; 55(95): 14371-14374, 2019 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-31720596

RESUMO

A facile template-engaged strategy is developed to synthesize hollow NiFe mixed metal oxyphosphide spheres using different Fe ions (Fe2+ and Fe3+) as modulators. Benefiting from the optimized compositional and structural features, the as-obtained hollow spheres show excellent performance for the oxygen evolution reaction.

6.
EBioMedicine ; 2019 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-31761615

RESUMO

BACKGROUND: Sleep disordered breathing (SDB) is a common disorder that results in oxidative stress and inflammation and is associated with multiple age-related health outcomes. Epigenetic age acceleration is a DNA methylation (DNAm)-based marker of fast biological aging. We examined the associations of SDB traits with epigenetic age acceleration. METHODS: A sample of 622 participants from the Multi-Ethnic Study of Atherosclerosis (MESA) had blood DNAm measured and underwent Type 2 in-home polysomnography that assessed apnea-hypopnea index (AHI), percentage of sleep time with oxygen saturation lower than 90% (Per90), and arousal index. DNAm data provided measures of DNAm-Age acceleration and DNAm-PhenoAge acceleration. The association of each SDB trait with age acceleration was estimated using linear regression, controlling for covariates. In secondary analyses, we studied the associations of SDB traits with epigenetic age acceleration 2-10 years after sleep study in 530 individuals from the Framingham Heart Study (FHS). FINDINGS: In MESA, AHI was associated with greater DNAm-PhenoAge acceleration (ß = 0.03; 95% CI [0.001, 0.06]). Arousal index was associated with greater DNAm-Age acceleration (ß = 0.04; 95% CI [0.01, 0.07]). Both associations were stronger in women than men. In the secondary FHS analyses, Per90 was associated with greater DNAm-Age acceleration and this association was stronger in men. INTERPRETATION: More severe SDB was associated with epigenetic age acceleration in both cohorts. Future work should prospectively study short- and long-term effects of SDB, and whether treatment reduces epigenetic age acceleration among those individuals with SBD. FUNDING: National Institutes of Health.

7.
Sci Rep ; 9(1): 16325, 2019 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-31704969

RESUMO

Tungsten disulfide (WS2) as one of transition metal dichalcogenides exhibits excellent catalytic activity. However, its catalytic performances in aqueous phase reactions are limited by its hydrophobicity. Here, the natural hydrophilic two-dimensional clay was used to enhance the dispersibility of WS2 in aqueous phase. WS2/montmorillonite (WS2/MMT) composite nanosheets were prepared via hydrothermal synthesis of WS2 on the surface of montmorillonite from WCl6 and CH3CSNH2. The microstructure and morphology show that WS2 nanosheets are assembled parallelly on the montmorillonite with the interface interaction. Through the support of montmorillonite, WS2/MMT possesses higher photocatalytic ability for aqueous phase reactions than WS2, which could be due to the synergistic effect of higher adsorption property, higher hydrophilicity, dispersibility and more catalytic reaction site. The strategy could provide new ideas for obtaining novel hydrophilic photocatalyst with excellent performance.

8.
Curr Pharm Des ; 2019 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-31692421

RESUMO

BACKGROUND: The current study was to examine the specific activation of pro-inflammatory cytokines (PICs), namely IL-1ß, IL-6 and TNF-α in the cochlear spiral ganglion of rats after ototoxicity induced by cisplatin. Since γ-aminobutyric acid (GABA) and its receptors are involved in pathophysiological processes of ototoxicity, we further examined the role played by PICs in regulating expression of GABA transporter type 1 and 3 (GAT-1 and GAT-3), as two essential subtypes of GATs responsible for the regulation of extracellular GABA levels in the neuronal tissues. METHODS: ELISA and western blot analysis were employed to examine the levels of PICs and GATs; and auditory brainstem response was used to assess ototoxicity induced by cisplatin. RESULTS: IL-1ß, IL-6 and TNF-α as well as their receptors were significantly increased in the spiral ganglion of ototoxic rats as compared with sham control animals (P<0.05, ototoxic rats vs. control rats). Cisplatin-ototoxicity also induced upregulation of the protein levels of GAT-1 and GAT-3 in the spiral ganglion (P<0.05 vs. controls). In addition, administration of inhibitors to IL-1ß, IL-6 and TNF-α attenuated amplification of GAT-1 and GAT-3 and improved hearing impairment induced by cisplatin. CONCLUSION: our data indicate that PIC signals are activated in the spiral ganglion during cisplatin-ototoxicity which thereby leads to upregulation of GABA transporters. As a result, it is likely that de-inhibition of GABA system is enhanced in the cochlear spiral ganglion. This support a role for PICs in engagement of the signal mechanisms associated with cisplatin-ototoxicity, and has pharmacological implications to target specific PICs for GABAergic dysfunction and vulnerability related to cisplatin-ototoxicity.

9.
Se Pu ; 37(11): 1241-1248, 2019 Nov 08.
Artigo em Chinês | MEDLINE | ID: mdl-31642279

RESUMO

A rapid method based on ultrahigh-performance liquid chromatography-quadrupole/electrostatic field orbitrap high-resolution mass spectrometry (UPLC-HRMS) was developed for the screening and confirmation of 20 mycotoxins in grain products. The samples were extracted with acetonitrile containing 2% (v/v) formic acid, and the extracts were cleaned up on Captive EMR-Lipid columns. The analytes were separated on a Thermo Hypersil Gold C18 column (100 mm×2.1 mm, 1.9 µm), and analyzed by UPLC-HRMS. The retention time and accurate mass of the parent ion were used for fast screening in full scan mode, while the accurate masses of the fragment ions were used for confirmation in the two-stage threshold-triggered full mass scan mode. The results revealed that the 20 mycotoxins showed good linear relationships in their respective mass concentration ranges. The correlation coefficients were not less than 0.99, and the limits of quantitation (LOQs) ranged from 0.25 to 20 µg/kg. The recoveries of the 20 mycotoxins in the sample ranged from 72.9% to 117.8% with the relative standard deviations (RSDs) from 2.9% to 15.2% at three spiked levels (n=6). This method has the advantages of high sensitivity and reliability, and is thus suitable for the rapid screening and confirmation of 20 mycotoxins in grain products.


Assuntos
Grão Comestível/química , Micotoxinas/análise , Cromatografia Líquida de Alta Pressão , Grão Comestível/microbiologia , Espectrometria de Massas , Reprodutibilidade dos Testes
10.
Clin Lab ; 65(10)2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31625354

RESUMO

BACKGROUND: Heat shock protein 60 has been reported to have a high diagnostic value for digestive system cancers. We sought to systematically evaluate the diagnostic value of HSP60 in patients with gastric cancer (GC), colorectal cancer (CRC), and hepatocellular carcinoma (HCC). METHODS: Relevant literature was adopted from the online databases. The pooled sensitivity, specificity, and diagnostic odds ratio (DOR) were pooled using random effects models. Summary receiver operating characteristic curve and the area under the curve (AUC) were used to express the overall test performance. Statistical analysis was performed by STATA 14.0 and Meta-DiSc 1.4 software. RESULTS: We merged 12 studies in a meta-analysis, including 1 GC, 5 CRC, and 6 HCC. Overall, the pooled sensitivity, specificity, and DOR to predict GC/CRC/HCC patients were 70%, 71%, and 8.49, respectively, corresponding to an AUC of 0.81. In subgroup analysis, the 82% specificity prompted a more advanced diagnostic accuracy for diagnosing CRC than HCC. CONCLUSIONS: HSP60 was an advanced biomarker for digestive system cancers and its abnormal expression might have implications for early diagnosis in screening of GC/CRC/HCC.

11.
Artigo em Inglês | MEDLINE | ID: mdl-31628088

RESUMO

PURPOSE: The aim of this study was to investigate the changes over a ten-year period in the resistance and epidemiological characteristics of Pseudomonas aeruginosa strains isolated from the Department of Respiratory in Southwest Hospital. METHODS: Antimicrobial resistance was detected using the plate double dilution method. PCR amplification and sequencing were performed to evaluate the carbapenemase genes and the oprD gene. Bacterial genotypes were analyzed by multilocus sequence typing (MLST). Quantitative real-time PCR experiments were performed to assess the expression of efflux pump (mexA and mexX) and ampC gene. RESULTS: We collected 233 P. aeruginosa isolates in 2006-2007 and 128 isolates in 2016-2017. The resistance rate of P. aeruginosa strains to the tested antibiotics was significantly lower in 2016-2017 than in 2006-2007. The MLST results showed 27 genotypes in 2006-2007 and 18 genotypes in 2016-2017. ST235 was the most prevalent sequence type, and there was no significant change in the genotypes over the ten-year period. Both VIM-2 and IMP-4 genes were found in 2006-2007, whereas only IMP-4 was found in 2016-2017. The oprD mutational inactivation was the main factor responsible for carbapenem resistance, and the overexpression of mexX had a good correlation with aminoglycoside resistance. CONCLUSION: These results indicated that the antibiotic resistance of P. aeruginosa in our respiratory department decreased. The loss of oprD gene was the main mechanism of carbapenem resistance, and mexX overexpression was the major contributing factor to aminoglycoside resistance.

12.
Eur J Pharm Sci ; 142: 105088, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31626963

RESUMO

The interaction of programmed death-1 (PD-1) and it's ligands (PD-L1) is an important immune checkpoint and blockade of PD-1/PD-L1 axis with antibodies against PD-L1 showed promising anti-tumor activity in clinical practice. However, only a small percentage of patients can benefit from PD-L1 mAbs. Small molecular kinase inhibitors have been widely used as antitumor drugs for many years, and several kinase inhibitors were recently reported to inhibit the expression of PD-L1. However, the connections between PD-L1 expression and kinase inhibitors were not thoroughly elucidated. Herein, we set up a novel and robust screening system to identify small molecular compounds which downregulate the PD-L1 level of tumor cell based on Odyssey on/in cell quantitative immunoblots technology. A collected kinase inhibitor library was screened and 14 hits were further confirmed by western blot and flow cytometry. System biological analysis and further bio-assay identified a synergy combination between KU-60019 and Vacquinol-1 in downregulation of PD-L1. Taken together, the work established a novel method to screen the PD-L1 down-regulators using kinase inhibitors library, thus providing new clues for the application of kinase inhibitors in cancer immunotherapy.

13.
Ecotoxicol Environ Saf ; 186: 109744, 2019 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-31627093

RESUMO

Biological strategy of utilization of plants-microbe's interactions to remediate cadmium (Cd) contaminated soils is effective and practical. However, limited evidence at transcriptome level is available about how microbes work with host plants to alleviate Cd stress. In the present study, comparative transcriptomic analysis was performed between maize seedlings inoculated with arbuscular mycorrhizal (AM) fungi and non-AM fungi inoculation under distinct concentrations of CdCl2 (0, 25, and 50 mg per kg soil). Significantly higher levels of Cd were found in root tissues of maize colonized by AM fungi, whereas, Cd content was reduced as much as 50% in leaf tissues when compared to non-AM seedlings, indicating that symbiosis between AM fungi and maize seedlings can significantly block translocation of Cd from roots to leaf tissues. Moreover, a total of 5827 differentially expressed genes (DEG) were determined and approximately 68.54% DEGs were downregulated when roots were exposed to high Cd stress. In contrast, 67.16% (595) DEGs were significantly up-regulated when seedlings were colonized by AM fungi under 0 mg CdCl2. Based on hierarchical clustering analysis, global expression profiles were split into eight distinct clusters. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis revealed that hundreds of genes functioning in plant hormone signal transduction, mitogen-activated protein kinase (MAPK) signaling pathway and glutathione metabolism were enriched. Furthermore, MapMan pathway analysis indicated a more comprehensive overview response, including hormone metabolism, especially in JA, glutathione metabolism, transcription factors and secondary metabolites, to Cd stress in mycorrhizal maize seedlings. These results provide an overview, at the transcriptome level, of how inoculation of maize seedlings by AM fungi could facilitate the relief of Cd stress.

15.
Pharmacogenomics J ; 2019 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-31636355

RESUMO

Clinical data on the relationships of cytochrome P450 (CYP2) B6 516G>T polymorphisms with efavirenz-induced central nervous system (CNS) side effects and virological response in HIV-infected adults are controversial. We sought to analyze the associations by meta-analysis. To identify eligible studies, we systematically searched PubMed, Embase, ScienceDirect, and Web of Science. The strength of the associations was measured by odds ratio (OR) and effect size (ES) with 95% confidence interval (CI). Seventeen studies comprising a total of 3598 HIV-infected adults were included. The results showed that the CYP2B6-516 GG genotype was significantly associated with a decreased risk of efavirenz-induced CNS side effects compared with the GT and TT genotypes (GG + GT vs. TT: OR = 0.60, 95% CI = 0.41-0.87, P = 0.006; GG vs. GT + TT: OR = 0.68, 95% CI = 0.51-0.91, P = 0.008; GG vs. GT: OR = 0.70, 95% CI = 0.51-0.94, P = 0.018), and there was no significant association between the genetic variants GT and TT (GT vs. TT: OR = 0.82, 95% CI = 0.54-1.26, P = 0.372). However, there was no significant association between CYP2B6-516 GG and GT + TT genotypes in virological response (GT + TT vs. GG: ES = 1.06, 95% CI = 0.95-1.18, P = 0.321; OR = 1.01, 95% CI = 0.65-1.58, P = 0.963). Taken together, our results demonstrated that compared with the normal efavirenz clearance genotype CYP2B6-516 GG, the slow and very slow efavirenz clearance genotypes GT and TT were significantly associated with an increased risk of efavirenz-induced CNS side effects but not an increased virological response. To promote the tolerance of efavirenz, it is better to adjust the dosage of efavirenz according to the polymorphisms of CYP2B6-516 in HIV-infected adults.

16.
Appl Microbiol Biotechnol ; 103(21-22): 8889-8898, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31656979

RESUMO

Quorum-quenching (QQ) enzymes can block the quorum-sensing (QS) system and prevent the expression of QS-controlled pathogenic factors in bacteria. However, the low expression levels of QQ proteins in the original host bacteria have affected their widespread application. In this study, we heterologously expressed momL, encoding a QQ enzyme with high activity, in Lysobacter enzymogenes. A "yellow-to-white" selection marker and the high-constitutive-expression promoter PgroEL were used in this novel heterologous expression system. In addition, we optimized the spacer between the SD sequence and the initiator to improve the efficiency of the expression system by 1.54-fold. The engineered strain LeMomL degraded the AHL molecule and the virulence factors of Pectobacterium carotovorum subsp. carotovora (Pcc). Additionally, LeMomL significantly decreased the disease caused by Pcc in Chinese cabbages and carrot root tissues. In conclusion, this novel and facile L. enzymogenes expression strategy has good prospects and is an ideal approach for foreign protein expression.

17.
Wei Sheng Yan Jiu ; 48(5): 785-792, 2019 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-31601319

RESUMO

OBJECTIVE: To analyze the current situation and correlation between frailty and cognitive dysfunction in the old patients of orthopedic emergency. METHODS: Enrolling 248 elderly people( ≥65 years old) in orthopedic emergency department of Beijing Jishuitan Hospital from September to December 2018, the cognitive function of the subjects was assessed by Mini-mental State Examination( MMSE). The frailty situation was assessed by FRAIL Scale. In addition, ADL, exercise tolerance assessment, gripping power and geriatric nutritional risk index( GNRI) were also tested in this study. RESULTS: In this research, 58( 23. 4%) were the elderly with normal cognitive function, 69( 27. 8%) were MCI, and 86( 34. 7%) were dementia and 35( 14. 1%) were severe dementia. The prevalence of seniors over 76 years old was significantly higher than that of the younger age group( χ~2= 39. 300, P < 0. 001), the prevalence of seniors below primary school was significantly higher than that of junior middle school and above( χ~2= 117. 082, P<0. 001), and the prevalence of dementia in patients with chronic obstructive pulmonary disease( COPD) was higher( χ~2= 11. 685, P = 0. 009). The study subjects were strong elderly, accounting for 69( 27. 8%), 114( 46. 0%) and 65( 26. 2%)were in prefrailty and frailty. The prevalence of prefrailty in 75-85 years old people was significantly higher than that in other groups, and the prevalence of prefrailty and frailty in85 years old people was both higher( χ~2= 45. 247, P<0. 001). In addition, education level( χ~2= 13. 909, P = 0. 008), hypertension( χ~2= 6. 892, P = 0. 032), COPD( χ~2= 8. 411, P =0. 015), cerebral infarction( χ~2= 7. 477, P = 0. 024) and GNRI( χ~2= 22. 942, P = 0. 001)were all the influencing factors of frailty. There were also significant differences in ADL, exercise tolerance and gripping power among the above factors. There were significant differences in cognitive function among subjects with different levels of frailty( χ~2=61. 259, P = 0. 000), ADL( χ~2= 54. 652, P<0. 001), exercise tolerance( χ~2= 77. 001, P =0. 000) and grip strength( χ~2= 54. 778, P < 0. 001). After adjusting for demographic characteristics and chronic diseases such as age, sex, education, BMI, coronary heart disease, hypertension and et al. Logistic regression analysis showed that the OR values of prefrailty, frailty, ADL and exercise tolerance affect cognition are 1. 918( 95% CI 0. 990-3. 716), 2. 732( 95%CI 1. 063-7. 023), 3. 217( 95% CI 1. 421-7. 285), 6. 440( 95% CI1. 803-22. 997). CONCLUSION: Prefrailty and frailty are closely related to cognitive dysfunction in the elderly.


Assuntos
Disfunção Cognitiva , Fragilidade , Avaliação Geriátrica , Idoso , Idoso de 80 Anos ou mais , Idoso Fragilizado , Humanos , Prevalência
18.
J Chemother ; : 1-8, 2019 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-31631801

RESUMO

Escherichia coli is a common pathogen of bacterial biofilm infections. Sub-minimum inhibitory concentration ceftazidime (sub-MIC CAZ) could inhibit the biofilm formation of E. coli. Deletion of the ibpAB genes could increase the extracellular indole concentration of E. coli and then inhibit biofilm formation. Therefore, we speculated that sub-MIC CAZ might inhibit biofilm formation via ibpAB. In this study, the results showed that sub-MIC CAZ could significantly inhibit biofilm formation, swimming motility and the expression of the ibpA gene, while it could increase the expression of tnaA gene and extracellular indole concentration. Knockout of the ibpA gene resulted in a decrease in biofilm formation and swimming motility and an increase in the indole concentration. When treated with sub-MIC CAZ, the tnaA gene expression, indole concentration, biofilm formation and swimming motility of MG1655 ΔibpA were similar to those of the control group. The results indicated that sub-MIC CAZ might inhibit the biofilm formation of E. coli by increasing the extracellular indole concentration and downregulating the ibpA gene.

19.
J Nanobiotechnology ; 17(1): 103, 2019 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-31581948

RESUMO

BACKGROUND: Immunocompromised individuals and those with lung dysfunction readily acquire pulmonary bacterial infections, which may cause serious diseases and carry a heavy economic burden. Maintaining adequate antibiotic concentrations in the infected tissues is necessary to eradicate resident bacteria. To specifically deliver therapeutics to the infected pulmonary tissues and enable controlled release of payloads at the infection site, a ROS-responsive material, i.e. 4-(hydroxymethyl) phenylboronic acid pinacol ester-modified α-cyclodextrin (Oxi-αCD), was employed to encapsulate moxifloxacin (MXF), generating ROS-responsive MXF-containing nanoparticles (MXF/Oxi-αCD NPs). RESULTS: MXF/Oxi-αCD NPs were coated with DSPE-PEG and DSPE-PEG-folic acid, facilitating penetration of the sputum secreted by the infected lung and enabling the active targeting of macrophages in the inflammatory tissues. In vitro drug release experiments indicated that MXF release from Oxi-αCD NPs was accelerated in the presence of 0.5 mM H2O2. In vitro assay with Pseudomonas aeruginosa demonstrated that MXF/Oxi-αCD NPs exhibited higher antibacterial activity than MXF. In vitro cellular study also indicated that folic acid-modified MXF/Oxi-αCD NPs could be effectively internalized by bacteria-infected macrophages, thereby significantly eradicating resident bacteria in macrophages compared to non-targeted MXF/Oxi-αCD NPs. In a mouse model of pulmonary P. aeruginosa infection, folic acid-modified MXF/Oxi-αCD NPs showed better antibacterial efficacy than MXF and non-targeted MXF/Oxi-αCD NPs. Meanwhile, the survival time of mice was prolonged by treatment with targeting MXF/Oxi-αCD NPs. CONCLUSIONS: Our work provides a strategy to overcome the mucus barrier, control drug release, and improve the targeting capability of NPs for the treatment of pulmonary bacterial infections.

20.
Sci Rep ; 9(1): 14393, 2019 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-31591457

RESUMO

Drought disaster space agglomeration assessment is one of the important components of meteorological disaster prevention and mitigation. Agriculture affected by drought disaster is not only a serious threat to world food security, but also an obstacle to sustainable development. Additionally, China is an important agricultural import and export country in the world. Therefore, we used the global Moran's I and the local indicators of spatial autocorrelation (LISA) to reveal the spatial agglomeration of agricultural drought disaster in China from1978 to 2016, respectively. The results showed that China's agricultural drought disaster presents local spatial autocorrelation of geographical agglomeration at national level during the study period. The spatial agglomeration regions of China's agricultural drought disaster were in Inner Mongolia, Jilin province, Heilongjiang province, Liaoning province, Shanxi province, Hebei province, Shandong province, Shaanxi province and Henan province, indicating that agricultural drought disaster mainly distributed in North and Northwest China, especially occurred in the Yellow River Basin and its north areas. We also found that the overall movement direction of agricultural drought disaster agglomeration regions was northwest, and the maximum moving distance was 722.16 km. Our results might provide insight in early warning and prevention for drought disaster.

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