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1.
Carbohydr Polym ; 228: 115359, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31635738

RESUMO

This study investigated the chain conformation, physicochemical properties of fucosylated chondroitin sulfate from Stichopus chloronotus (fCS-Sc) using HPSEC-MALLS and worm-like cylinder model methods and its impact on human gut microbiota by 16s RNA gene sequencing. The results indicated that fCS-Sc adopted rigid rods chain conformation in PBS based on chain conformational parameters αη (1.11) and αh (0.70). Stiffness parameters deduced from worm-like cylinder model suggested that fCS-Sc exhibited as stiff chains. The congo red assay indicated a single-helical structure. fCS-Sc demonstrated a negative zeta-potentials in a wide pH ranges and good thermal stability. Besides, fCS-Sc could modulate the community structure of gut microbiota by elevating the absolute abundance of microbiota, increasing the beneficial bacterium Megamonas, Bacteroides, Fusobacterium, Parabacteroides, Prevotella, Faecalibacterium, suppressing pathogenic microorganism and promoting the short-chain fatty acids production. The present studies improved the understanding of the spatial structures of fCSs and its application as prebiotics.

2.
J Hazard Mater ; 383: 121169, 2020 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-31520931

RESUMO

Nickel (Ni) contamination in soils, at high concentrations, is considered to be very common. Knowledge of the total content of Ni is frequently insufficient to estimate environmental risk. Our explored findings showed that the earthworms adding reduced the available Ni, along with the superior performance of HCl than CaCl2. The bioaccumulation of Ni in earthworms was aggravated with increasing Ni dosage and exposure time. Bioaccumulation factor was significantly correlated with the extractable Ni, which was the most suitable predicting the variations of Ni bioavailability. LC50 of earthworms on 7 and 14 days were 1202.444 mg kg-1 and 1069.324 mg kg-1, respectively along with the recovery rate in 500 mg kg-1 Ni polluted soil reached up to 92.5%. Earthworms' respiration was sensitive presenting a significant dose-effect relationship with the Ni concentration. Five biochemical indices in earthworms were induced along with the relevance of a dose- and time-response pattern. Additionally, histological damage in earthworm's body wall, intestine and seminal vesicles were observed under high level of Ni exposure. Overall, we believe that our current study will open a new window for deeper insights into the potential availability of Ni along with other associated metals on the function of soil ecosystem.

3.
J Mol Cell Cardiol ; 137: 107-118, 2019 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-31668970

RESUMO

Cardiac fibrosis is a common feature of various cardiovascular diseases. Previous studies showed that acetaldehyde dehydrogenase 2 (ALDH2) deficiency exacerbated pressure overload-induced heart failure. However, the role and mechanisms of cardiac fibrosis in this process remain largely unknown. This study aimed to investigate the effect of ALDH2 deficiency on cardiac fibrosis in transverse aortic constriction (TAC) induced pressure overload model in mice. Echocardiography and histological analysis revealed cardiac dysfunction and enhanced cardiac fibrosis in TAC-operated animals; ALDH2 deficiency further aggravated these changes. ALDH2 chimeric mice were generated by bone marrow (BM) transplantation of WT mice into the lethally irradiated ALDH2KO mice. The proportion of circulating fibroblast progenitor cells (FPCs) and ROS level in BM after TAC were significantly higher in ALDH2KO mice than in ALDH2 chimeric mice. Furthermore, FPCs were isolated and cultured for in vitro mechanistic studies. The results showed that the stem cell-derived factor 1 (SDF-1)/C-X-C chemokine receptor 4 (CXCR4) axis played a major role in the recruitment of FPCs. In conclusion, our research reveals that increased bone marrow FPCs mobilization and myocardial homing contribute to the enhanced cardiac fibrosis and dysfunction induced by TAC in ALDH2 KO mice via exacerbating accumulation of ROS in BM and myocardial SDF-1 expression.

4.
Int J Cardiol ; 2019 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-31685245

RESUMO

BACKGROUND: Obesity is often considered as a risk factor of cardiovascular events, but recent researches showed conflicting results regarding to the effect of body weight on prognosis of coronary artery disease (CAD). This study aimed to evaluate the relationship between body mass index (BMI) and clinical outcomes of CAD in Asian population. METHODS: A total of 4315 patients from the FOCUS registry were enrolled into this analysis. Patients were divided into 4 groups according to BMI: lean group (BMI<18.5 kg/m2), normal group (BMI 18.5-24.9 kg/m2), overweight group (BMI 25-30 kg/m2) and obesity group (BMI>30 kg/m2). Follow-up was continued to 3 years to evaluate clinical outcomes, and the primary endpoint was a composite of all-cause death and myocardial infarction (MI). RESULTS: Patients with higher BMI were more likely to be associated with cardiovascular risk factors like hypertension, hypercholesterolemia and diabetes, but not smoking. At the end of the follow-up period, however, the incidence of a composite endpoint of all-cause death and MI was significantly lower in the higher BMI (overweight and obese) subsets, as compared with the lower BMI group (5.2% vs. 8.0%, p < 0.001). So did the cumulative rates of all-cause death (p < 0.001), cardiovascular death (p < 0.001), and a combined endpoint of cardiovascular death and MI (p = 0.001). CONCLUSIONS: In Asian patients with CAD, an inverse association between BMI and long-term prognosis was observed. Although overweight or obese patients were associated with more metabolism-associated comorbidities, they had significantly lower adverse events at 3-year follow up after percutaneous coronary intervention.

5.
Artigo em Inglês | MEDLINE | ID: mdl-31685424

RESUMO

Two novel ruthenium(II) polypyridyl complexes, namely, [Ru(dmp)2(CAPIP)](ClO4)2 (Ru(II)-1) and [Ru(dmp)2(CFPIP)](ClO4)2 (Ru(II)-2), which respectively contain (E)-2-(2-(furan-2-yl)vinyl)-1H-imidazo[4,5-f][1,10]phen-anthroline (CAPIP) and (E)-2-(4-fluorostyryl)-1H-imidazo[4,5-f][1,10]phenanthroline. (CFPIP), were first designed and characterized (dmp = 2,9-dimethyl-1,10-phenanthroline). DNA binding experiments indicated that Ru(II) complexes interact with CT DNA through intercalative mode. In addition, the complexes Ru(II)-1 and Ru(II)-2, showed remarkable cell cytotoxicity, giving the respective IC50 values of 4.1 ±â€¯1.4 µM and 6.1 ±â€¯1.4 µM on the A549 cancer cells. These values indicated higher activity than CAPIP, CFPIP, cisplatin (8.2 ±â€¯1.4 µM) and other corresponding Ru(II) polypyridyl complexes. Furthermore, the Ru(II) complexes could arrive the cytoplasm through the cell membrane and accumulate in the mitochondria. Significantly, complexes Ru(II)-1 and Ru(II)-2 induced A549 cells apoptosis was mediated by increase of ROS levels and dysfunction of mitochondria, and resulted in cell cycle arrest and increased anti-migration activity on A549 cells. Overall, these results indicated that complexes Ru(II)-1 and Ru(II)-2 could be suitable candidates for further investigation as a chemotherapeutic agent in the treatment of tumors.

6.
Dalton Trans ; 48(44): 16776-16785, 2019 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-31674607

RESUMO

A novel metal-organic framework with the formula [Zn3(DDB)(DPE)]·H2O (1) (H5DDB = 3,5-di(2',4'-dicarboxylphenyl)benzoic acid and DPE = 1,2-di(4-pyridyl)ethylene) has been solvothermally synthesized by employing a rigid carboxylate ligand H5DDB to assemble with Zn(ii) ions in the presence of a flexible bis(pyridyl) linker DPE. The Zn-MOF is a 3D framework with six-nuclear clusters and possesses remarkable water stability and pH stability. Interestingly, complex 1 can sensitively and selectively sense Fe(iii), Cr(iii), Cr(vi), Mn(vii) and the pesticide 2,6-Dich-4-NA with low detection limits in aqueous solution. Moreover, complex 1 also exhibits selectivity for 2,6-Dich-4-NA detection in real samples including carrot, grape and nectarine extracts, and its detection ability is almost unchanged in the presence of the surfactant sodium dodecyl sulfate (SDS). The possible mechanisms of luminescence quenching have been explained by the weak affinity of nitrogen atoms, resonance energy transfer, and photoinduced electron transfer. To our knowledge, this is the first example of a MOF-based multiresponsive fluorescent probe for the simultaneous detection of Fe(iii), Cr(iii/vi), Mn(vii) and the pesticide 2,6-Dich-4-NA in aqueous solution.

7.
BMC Neurol ; 19(1): 274, 2019 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-31699038

RESUMO

BACKGROUND: Early prediction of unfavorable outcome after ischemic stroke is of great significance to the clinical and therapeutic management. A nomogram is a better visual tool than earlier models and prognostic scores to predict clinical outcomes, which incorporates different factors to develop a graphic continuous scoring system and calculates accurately the risk probability of poor outcome entirely based on individual characteristics. However, to date, no nomogram models have been found to predict the probability of 6-month poor outcome after ischemic stroke. We aimed to develop and validate a nomogram for individualized prediction of the probability of 6-month unfavorable outcome in Chinese patients with ischemic stroke. METHODS: Based on the retrospective stroke registry, a single-center study which included 499 patients from May, 2013 to May, 2018 was conducted in Nanjing First Hospital (China) for ischemic stroke within 12 h of symptoms onset. The main outcome measure was 6-month unfavorable outcome (mRS > 2). To generate the nomogram, NIHSS score on admission, Age, previous Diabetes mellitus and crEatinine (NADE) were integrated into the model. We assessed the discriminative performance by using the area under the curve (AUC) of receiver-operating characteristic (ROC) and calibration of risk prediction model by using the Hosmer-Lemeshow test. RESULTS: A visual NADE nomogram was constructed that NIHSS score on admission (OR: 1.190, 95%CI: 1.125-1.258), age (OR: 1.068, 95%CI: 1.045-1.090), previous diabetes mellitus (OR: 1.995, 95%CI: 1.236-3.221) and creatinine (OR: 1.010, 95%CI: 1.002-1.018) were found to be significant predictors of 6-month unfavorable outcome after acute ischemic stroke in Chinese patients. The AUC-ROC of nomogram was 0.791. Calibration was good (p = 0.4982 for the Hosmer-Lemeshow test). CONCLUSION: The NADE is the first nomogram developed and validated in Chinese ischemic stroke patients to provide an individual, visual and precise prediction of the risk probability of 6-month unfavorable outcome.

8.
Hypertens Res ; 2019 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-31700166

RESUMO

Atrial fibrillation (AF) is the most common human arrhythmia in clinical practice and may be promoted by atrial inflammation and fibrosis. Ubiquitination is an important posttranslational modification process that is reversed by deubiquitinating enzymes (DUBs). DUBs play critical roles in modulating the degradation, activity, trafficking, and recycling of substrates. However, less research has focused on the role of DUBs in AF. Here, we investigated the effect of ubiquitin C-terminal hydrolase 1 (UCHL1), an important DUB, on the development of AF induced by angiotensin II (Ang II). Male wild-type mice were treated with the UCHL1 inhibitor LDN57444 (LDN) at a dose of 40 µg/kg and infused with Ang II (2000 ng/kg/min) for 3 weeks. Our results showed that Ang II-infused wild-type (WT) mice had higher systolic blood pressure and an increased incidence and duration of AF. Conversely, this effect was attenuated in LDN-treated mice. Moreover, the administration of LDN significantly reduced Ang II-induced left atrial dilation, fibrosis, inflammatory cell infiltration, and reactive oxygen species (ROS) production. Mechanistically, LDN treatment inhibited the activation of multiple signaling pathways (the AKT, ERK1/2, HIF-1α, and TGF-ß/smad2/3 pathways) and the expression of CX43 protein in atrial tissues compared with that in vehicle-treated control mice. Overall, our study identified UCHL1 as a novel regulator that contributes to Ang II-induced AF and suggests that the administration of LDN may represent a potential therapeutic approach for treating hypertensive AF.

9.
Artigo em Inglês | MEDLINE | ID: mdl-31702120

RESUMO

Preterm birth and its complications are the leading cause of neonatal death. The main underlying pathological mechanisms for preterm complications are disruption of the normal maturation processes within the target tissues, interrupted by premature birth. Cord blood, as a new and convenient source of stem cells, may provide new, promising options for preventing preterm complications. This prospective, nonrandomized placebo controlled study aims at investigating the effect of autologous cord blood mononuclear cells (ACBMNC) for preventing preterm associated complications. Preterm infants less than 35 weeks gestational age were assigned to receive ACBMNC (5 × 107 cells/kg) intravenous or normal saline within 8 hours after birth. Preterm complications rate were compared between two groups to demonstrate the effect of ACBMNC infusion in reducing preterm complications. Fifteen preterm infants received ACBMNC infusion, and 16 infants were assigned to control group. There is no significant difference when comparing mortality and preterm complications rate before discharge home. However, ACBMNC infusion demonstrated significant decreases in duration of mechanical ventilation (3.2 days vs 6.41 days, P = .028) and oxygen therapy (5.33 days vs 11.31 days, P = .047). ACBMNC infusion was effective in reducing respiratory support duration in very preterm infants. Due to the limited number of patients enrolled, powered randomized controlled trials are needed to better define its efficacy. Stem Cells Translational Medicine 2019.

10.
Surg Obes Relat Dis ; 2019 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-31734065

RESUMO

BACKGROUND: Although the number of weight loss procedures is increasing, bariatric surgery is not used equitably in the United States. As obesity is more prevalent in minorities, higher priorities are placed toward improvement of access to care for these groups. OBJECTIVES: To evaluate whether patient insurance status has any effect on use of bariatric surgery for patients in New York State. SETTING: Administrative statewide database. METHODS: The Statewide Planning and Research Cooperative System administrative database was used to identify all patients undergoing primary bariatric procedures between 2005 and 2016. Revision procedures were excluded from analysis. Multivariable logistic regression models were used to compare outcomes among patients with different payor status after controlling for confounding factors. RESULTS: After the application of inclusion and exclusion criteria, there were 125,666 bariatric records from 2005 to 2016. Most patients had commercial insurance (n = 106,148, 84.5%), followed by Medicare (n = 9355, 7.4%), Medicaid (n = 7939, 6.3%), and other/unknown (n = 2224, 1.8%). The percentage of Medicaid was estimated to be increase by 12%/yr and the percentage of Medicare was estimated to be increase by 5%/yr during 2005 to 2016. Univariate analysis showed that patients with different insurance types were significantly different in terms of age, sex, race, region, subtype of surgeries, most co-morbidities, overall complication, 30-day readmission/emergency department visits, and length of stay (P values < .0001). After adjusting for other confounding factors, patients with Medicare insurance had significantly higher risk of having overall complications, 30-day readmissions/emergency department visits, and longer length of stay. CONCLUSIONS: The majority of patients undergoing bariatric surgery are insured by private insurance, whereas only 13.7% of bariatric surgeries are performed on patients with public insurance.

11.
J Sex Med ; 2019 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-31735614

RESUMO

INTRODUCTION: Premature ejaculation (PE) is a highly prevalent male sexual dysfunction. Previous studies have found abnormal activity in the sympathetic nervous system and penile sensory pathway of PE. Few studies have investigated the neural mechanisms underlying PE. AIM: The aim of this study was to examine whether the altered cortico-subcortical network topological properties of the brain white matter structural network could be used to differentiate patients with PE from healthy control (HC) subjects. METHODS: Diffusion tensor images data were collected from 32 patients with PE and 35 HC participants. Then, brain white matter structural networks were reconstructed from image acquisition. MAIN OUTCOME MEASURE: Furthermore, nodal measures were calculated and hub regions were identified using the graph-theoretical methods. RESULTS: For cortical brain regions, increased strength, global efficiency, and decreased shortest path length were found in the right superior frontal gyrus (medial), and superior frontal gyrus (medial orbital) were found in patients with PE. In addition, patients with PE also showed decreased strength in the right rolandic operculum and decreased shortest path length, and increased global efficiency in the right inferior frontal gyrus (triangular part). For subcortical brain structures, patients with PE were associated with decreased shortest path length and increased global efficiency in the left insula and right caudate nucleus. Finally, the results showed that 9 PE-specific hub regions were identified in patients compared with HCs, including 7 cortical regions and 2 subcortical regions. CLINICAL IMPLICATIONS: Our results provide new understanding about the pathology of PE and enhances the understanding of PE pathology. STRENGTH & LIMITATIONS: Our results offer biological markers for understanding the physiopathology of PE. However, our study is a cross-sectional design, longitudinal design studies need to explore the causal relationships between aberrant topological characteristics and PE. CONCLUSION: Our results provide new insights into the neural mechanism of PE involving cortico-subcortical network changes, which could serve as a potential biomarker to differentiate individuals with PE from HCs. Chen J, Yang J, Huang X, et al. Variation in Brain Subcortical Network Topology Between Men With and Without PE: A Diffusion Tensor Imaging Study. J Sex Med 2019;XX:XXX-XXX.

12.
Anal Chem ; 2019 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-31714070

RESUMO

Rapid capture and identification of the intracellular target genes of microRNAs (miRNAs) are the key to understanding miRNA functions and development of RNA-based therapeutics. However, developing biochemical tools that can fish out the target genes of miRNAs in live cells is a significant technical challenge. Here, we report a remarkably simple yet powerful technology capable of loading virtually any miRNA into Ago2 of the RNA-induced silencing complexes (RISCs). This surprising discovery enables rapid capture and identification of target mRNAs and long noncoding RNAs. It is achieved by linking dibenzocyclooctyne (DBCO), a classical chemical moiety in copper-free click chemistry, to the 3' end of miRNAs. DBCO serves as a high-affinity tag to the Ago2 protein, thus boosting the formation of RISCs with miRNA target genes in living cells. Upon cell lysing, DBCO's routine function in click chemistry allows rapid enrichment of target genes for analysis without the need of additional molecular handles. A series of miR-21 and miR-27a target genes that were previously unknown were pulled down from various cell lines and identified with qRT-PCR, demonstrating the utility of this innovative technology in both transcriptomic research and RNA-based studies.

13.
J Orthop Surg Res ; 14(1): 382, 2019 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-31752900

RESUMO

BACKGROUND: Geriatric hip fracture is a common type of osteoporotic fracture with high mortality and disability; surgical site infection (SSI) can be a devastating complication of this injury. By far, only a few studies identified easily remediable factors to reduce infection rates following hip fracture and less researches have focused on geriatric patients. The objective of this study was to identify potentially modifiable factors associated with SSI following geriatric hip fracture surgery. METHODS: This retrospective, multicenter study involves three level I hospitals. A total of 1240 patients (60 years or older) underwent hip surgery with complete data were recruited between January 2016 and June 2018. Demographics information, medications and additional comorbidities, operation-related variables, and laboratory indexes were extracted and analyzed. Receiver operating characteristic (ROC) analysis was performed to detect the optimum cut-off value for quantitative data. Univariate and multivariate logistic analysis model were performed respectively to identify the independent predictors. RESULTS: Ninety-four (7.58%) patients developed SSI in this study, and 76 (6.13%) had superficial infection, while 18 (1.45%) were diagnosed with deep infection. Results of univariate and multivariate analysis showed age > 79 years (OR, 2.60; p < 0.001), BMI > 26.6 kg/m2 (OR, 2.97; p < 0.001), operating time > 107 min (OR, 2.18; p = 0.001), and ALB < 41.6 g/L (OR, 2.01; p = 0.005) were associated with an increased incidence of SSI; drainage use (OR, 0.57; p = 0.007) could reduce the incidence of wound infection for patients after geriatric hip fracture. CONCLUSION: Accurate modifiable variables, operating time > 107 min, serum albumin < 41.6 g/L, BMI > 26.6 kg/m2, and age > 79 years could be applied to distinguish geriatric patients with high-risk of postoperative surgical site infection.

14.
J Agric Food Chem ; 2019 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-31746600

RESUMO

We compared phospholipids (PLs), PLs fatty acid (FA) composition and milk fat globules size and structure in human milk (n = 120) from mothers of full-term and preterm infants during lactation (colostrum, transition, 1 mo, 2 mo, and 3 mo) and 8 brands of infant formulae. The absolute quantification of PLs was analyzed using 31P NMR spectroscopy. Sphingomyelin (SM) was the dominant PLs (35.01 ± 3.31%) in human milk, whereas phosphatidylcholine (PC) and phosphatidylethanolamine (PE) were the dominant PLs in infant formulae. The PLs content in preterm milk increased during lactation, whereas that in term milk remained stable. Saturated FAs (mainly 16:0 and 18:0) were the most abundant (>60%) PLs FA in both preterm and term milk and increased throughout lactation. The mean diameter of milk fat globules in infant formulae was much smaller than that found in human milk (200 nm vs 5.63 µm). Significant differences were observed between human milk and infant formulae with regard to PLs, suggesting that more research is needed to mimic the PLs profile in infant formula.

15.
Neural Netw ; 122: 117-129, 2019 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-31677440

RESUMO

Along with the explosive growing of data, semi-supervised learning attracts increasing attention in the past years due to its powerful capability in labeling unlabeled data and knowledge mining. As an emerging method, the semi-supervised extreme learning machine (SSELM), that builds on ELM, has been developed for data classification and shown superiorities in learning efficiency and accuracy. However, the optimization of SSELM as well as most of the other ELMs is generally based on the mean square error (MSE) criterion, which has been shown less effective in dealing with non-Gaussian noises. In this paper, a robust regularized correntropy criterion based SSELM (RC-SSELM) is developed. The optimization of the output weight matrix of RC-SSELM is derived by the fixed-point iteration based approach. A convergent analysis of the proposed RC-SSELM is presented based on the half-quadratic optimization technique. Experimental results on 4 synthetic datasets and 13 benchmark UCI datasets are provided to show the superiorities of the proposed RC-SSELM over SSELM and other state-of-the-art methods.

16.
J Virol Methods ; : 113774, 2019 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-31726113

RESUMO

Porcine Reproductive and Respiratory Syndrome (PRRS), an acute infectious disease caused by the porcine reproductive and respiratory syndrome virus (PRRSV), is one of the most devastating diseases affecting the global swine industry. In order to establish a multiplex real-time PCR method for the simultaneous detection of the classical PRRSV (C-PRRSV) strain, the highly pathogenic PRRSV (HP-PRRSV) strain and NADC30-like PRRSV (NL-PRRSV) strain, we designed specific primers and TaqMan fluorescent probes based on the Nsp2 target gene sequence of these three different PRRSV strains, and designed American-type PRRSV (PRRSV-U) special primers and probes based on the relatively conserved target gene sequence of ORF7. The method established in this study can quickly and accurately detect and differentiate three types of strains of clinical tissue samples, respectively. This method plays a key role in the rapid diagnosis and determination of PRRSV.

17.
Small ; : e1903663, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31729163

RESUMO

Bismuth ferrite (BiFeO3 ) has recently become interesting as a room-temperature multiferroic material, and a variety of prototype devices have been designed based on its thin films. A low-cost and simple processing technique for large-area and high-quality BiFeO3 thin films that is compatible with current semiconductor technologies is therefore urgently needed. Development of BiFeO3 thin films is summarized with a specific focus on the chemical solution route. By a systematic analysis of the recent progress in chemical-route-derived BiFeO3 thin films, the challenges of these films are highlighted. An all-solution chemical-solution deposition (AS-CSD) for BiFeO3 thin films with different orientation epitaxial on various oxide bottom electrodes is introduced and a comprehensive study of the growth, structure, and ferroelectric properties of these films is provided. A facile low-cost route to prepare large-area high-quality epitaxial BFO thin films with a comprehensive understanding of the film thickness, stoichiometry, crystal orientation, ferroelectric properties, and bottom electrode effects on evolutions of microstructures is provided. This work paves the way for the fabrication of devices based on BiFeO3 thin films.

18.
Analyst ; 144(23): 6866-6870, 2019 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-31670735

RESUMO

Surfactants play important roles in chemical industries and have become well-known environmental pollutants owing to their extensive use in different fields. In this work, we reported a fluorescent probe, namely, BDP-Zn2+ for the discrimination of four kinds of surfactants and the determination of CMC values. BDP-Zn2+ was composed of covalently linked BODIPY, carbazole, N,N-bis(2-pyridylmethyl)ethylenediamine (BPEA) and zinc ions to fabricate a novel push-pull molecular structure. Upon the addition of surfactants, the probe exhibited a turn-on fluorescence response and the emission was enhanced on increasing the surfactant concentrations. This indicated that the fluorescence intensity and the ratios of the emission at 607 nm to that at 514 nm as fingerprints could be used to identify the CMC values of the surfactants. Our current work provides an alternative method to efficiently discriminate different surfactants for the further studies of their physical and chemical functions.

19.
Artigo em Inglês | MEDLINE | ID: mdl-31741271

RESUMO

Bioaerosols are an important component of particulate matter in the atmosphere and are harmful to human health. In this study, the concentration, size distribution, and factors influencing culturable airborne bacteria and fungi in the atmosphere were investigated using a six-stage impactor device in the city of Xinxiang, China, during the winter season. The results revealed that the concentration of culturable airborne bacteria and fungi varied significantly during the sampling period: 4595 ± 3410 and 6358 ± 5032 CFU/m3, respectively. The particle sizes of the bioaerosols were mainly within stage V (1.1-2.1 µm), and fine particulate matter accounted for 45.9% ± 18.9% of airborne bacteria and 52.0% ± 18.5% of airborne fungi, respectively. With the deterioration of air quality, the concentration of airborne fungi gradually increased, and that of airborne bacteria increased when the air quality index was lower than 200 and decreased when it was higher than 200. With respect to the diurnal variation pattern of bioaerosol concentration, the highest and lowest concentrations were registered at night and noon, respectively, probably because of changes in ultraviolet radiation intensity. Bioaerosol concentration positively correlated with humidity, concentration of PM2.5, PM10, SO2, and NO2 and negatively correlated with O3 concentration. The risk of exposure of humans to the airborne bacteria was primarily associated with the respiratory inhalation pathway, and the risk of skin exposure was negligible. These results should improve our understanding of the threat of bioaerosols to public health.

20.
Pathog Dis ; 77(6)2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31702775

RESUMO

Generally, influenza virus neuraminidase (NA) plays a critical role in the release stage of influenza virus. Recently, it has been found that NA may promote influenza virus to access the target cells. However, the mechanism remain unclear. Here, we reported that peramivir indeed possessed anti-influenza A virus (IAV) activity in the stage of viral entry. Importantly, we verified the critical residues of influenza NA involved in the viral entry. As a result, peramivir as an efficient NA inhibitor could suppress the initiation of IAV infection. Furthermore, mutational analysis showed NA might be associated with viral entry via amino acids residues R118, E119, D151, R152, W178, I222, E227, E276, R292 and R371. Our results demonstrated NA must contain the key amino acid residues can involve in IAV entry.

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