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1.
Chemosphere ; 239: 124704, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31520983

RESUMO

Parabens (p-hydroxybenzoic acids) are commonly used as preservatives in personal care products. Although the rate of exposure to a single product may be small, it is possible for an individual to have marked exposure to parabens through the use of multiple personal care products (aggregate exposure). To assess the risks associated with aggregate exposure to parabens, we estimated the dermal exposure rate distributions of four major parabens (methylparaben, MP; ethylparaben, EP; propylparaben, PP; butylparaben, BP) in various products for women (>20 years old) and children (1-3 years old) by using the probabilistic exposure assessment tool ConsExpo. Integrated exposure rates were then calculated as the sum of exposure rates for individual products. Aggregate exposure rates for women were 1.2 (median) (0.13 [5%ile], 6.9 [95%ile]), 0.43 (0.029, 3.0), 0.35 (0.032, 1.9), and 0.25 (0.027, 1.2) mg kg-bw-1 day-1 for MP, EP, PP, and BP, respectively. Those for children were 0.47 (0.054, 2.2), 0.11 (0.012, 0.60), 0.13 (0.012, 0.78), and 0.13 (0.0065, 0.85) mg kg-bw-1 day-1 for MP, EP, PP, and BP, respectively. Integrated exposure rates for women were several times those for children. In both cases, personal care products that were applied to larger areas of skin and were used more frequently were more likely to be associated with higher exposure rates. According to the results of a risk assessment using a margin of exposure approach, aggregate rates of exposure to PP and BP, but not MP or EP, were high enough to warrant concern about disruption of the reproductive system.

2.
Chemosphere ; 240: 124929, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31561158

RESUMO

An UV enhanced electro-Fenton (EF) process was conducted in a flow-through system to remove rhodamine B (RhB) in the presence of ethylenediamine tetraacetate (EDTA). The process was denoted as UV/EDTA/EF where EDTA formed complexes with iron ions, thus keeping them soluble at high pH values. The process was very efficient as it could initiate the fast reduction of FeIII to FeII and thus the decomposition of H2O2. The influence of Fe dose, the ratio of EDTA:Fe, aeration rate, flow rate, current, initial RhB concentration and pH on the RhB removal in the UV/EDTA/EF process was investigated. The best RhB removal was obtained as 89.9% at [Fe]0 = [EDTA]0 = 0.2 mM, current = 50 mA, aeration rate = 20 mL min-1, flow rate = 7 mL min-1, pH = 7 and [Na2SO4]0 = 0.05 M. The degradation of EDTA during the process was also studied. Radical scavenging experiments indicated that OH was the dominant radical for RhB removal. While, the photolysis of FeIIIEDTA was mainly responsible for EDTA degradation. RhB and EDTA removal in different systems was compared. The stability test proved that in the presence of EDTA, the UV/EF process could remove RhB with high efficiency in the first two runs. While, the efficiency dropped remarkably after EDTA's complete depletion. The mechanisms of the UV/EDTA/EF process were proposed. UV/EDTA/EF conducted in the flow-through system was able to efficiently remove RhB as well as EDTA in a wide pH range and proposed as a promising approach for wastewater treatment.

3.
Food Chem ; 305: 125454, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31505413

RESUMO

The effects of the (-)-Epigallocatechin gallate (EGCG)-gelatin biofilm treatment (EGT) on microbial composition and quality of tilapia fillets stored at low temperatures were evaluated. The changes in mechanical properties, microbial reproduction, as well as lipid and protein oxidation during fillets storage were determined. The results showed that EGT reduced the microbial count and the relative abundance of the fillets. And EGT delayed the rate of lipid oxidation and protein denaturation in fillets. Compared with the control group, EGT samples had lower K values (74% on 18 d) and biogenic amines (39 mg/kg for putrescine and 50 mg/kg for cadaverine on 21 d). According to sensory evaluation, the shelf life of tilapia fillets was extended by 6 d in the EGT group. Therefore, EGT improved the quality of cryopreserved tilapia fillets and could be considered as a potential method for fish fillet preservation.

4.
J Phys Condens Matter ; 32(1): 015601, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31509821

RESUMO

We present a detailed magnetotransport study on HfB2, a possible topological nodal-line semimetal. HfB2 exhibits field-induced resistivity upturn and plateau behaviors at low temperature and high field, accompanying rather large magnetoresistance. The analysis of the field dependence of Hall and longitudinal resistivity shows that there are two kinds of carriers (electrons and holes) with almost same carrier concentrations and rather high mobilities in HfB2. Above field-induced phenomena can be well explained by using the two-band model with compensation condition. Even the carrier concentration is significantly high (∼1.8 [Formula: see text] 1021 cm-3) in HfB2, much larger than other known topological semimetals with discrete Dirac nodal points, the electron-type carriers still have relatively small effective masses. In contrast to ZrB2, the slightly increased effective mass in HfB2 manifests the effect of enhanced spin-orbit coupling due to the large atomic number of Hf.

5.
J Nanosci Nanotechnol ; 20(3): 1838-1844, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31492350

RESUMO

Pt/Bi2WO6 composite photocatalysts were prepared by a facile photoreduction method. Pt nanoparticles with an average size of 5-8 nm were successfully deposited on the surface of Bi2WO6 microspheres and the photocatalytic activity of Bi2WO6 was greatly improved by Pt nanoparticles. The photo-induced charge transfer properties of samples were studied by means of surface photovoltage (SPV) and transient photovoltage (TPV) techniques, giving an insight into the intrinsic reasons of the improvement in photocatalytic activity. The SPV and TPV results revealed that the deposited Pt nanoparticles could trap photo-induced electrons and then largely enhance the separation efficiency of photo-induced charge carriers.

6.
J Cyst Fibros ; 2019 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-31727452

RESUMO

BACKGROUND: The relation between malnutrition and pulmonary death in patients with cystic fibrosis (CF) has resulted in intensive nutritional intervention over the last few decades, leading to a significant decline in underweight and the emergence of overweight/obesity as a potential new problem. METHODS: We performed a cross-sectional database analysis of 484 adults with CF seen at the University of Minnesota CF Center between January 2015-January 2017, to determine the prevalence and pulmonary/cardiovascular risk factors associated with overweight and obesity in this population. RESULTS: Mean age was 35.2 ±â€¯11.6 years. 5.2% were underweight (BMI<18.5 kg/m2), 62.6% normal weight (BMI ≥ 18.5-24.9 kg/m2), 25.6% overweight (BMI ≥ 25-29.9 kg/m2) and 6.6% obese (BMI ≥ 30 kg/m2). In the subgroup with severe genotypes, 25% had BMI ≥ 25 kg/m2. In the entire cohort, overweight/obese were likely to be older (OR = 1.04, p < 0.0001) and to have a mild CFTR genotype (OR = 3.33, p = 0.0003) and modestly elevated triglyceride levels (OR = 1.008, p < 0.0001). The prevalence of hypertension was higher in overweight (25%) and obese (31%) than normal (17%) or underweight (16%), p = 0.01. Total cholesterol levels were higher in overweight/obese versus normal/underweight (144-147 vs 123-131 mg/dL, p = 0.04) as were LDL levels (70-71 vs 53-60 mg/dL, p = 0.02), but all were within the normal range. Percent predicted FEV1 was higher in overweight/obese (78-81%) versus underweight (59%) and normal (70%), p < 0.0001, and overweight/obese experienced significantly fewer acute pulmonary exacerbations. CONCLUSIONS: Overweight/obesity is common in adults with CF including those with severe genotypes. Lung function is better in the overweight/obese and lipid levels are within the normal range, albeit higher than in normal/underweight.

7.
Plant Cell Rep ; 2019 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-31728702

RESUMO

KEY MESSAGE: RsMYB1a was the crucial MYB, and RsbHLH4 is the essential partner in regulating the anthocyanin biosynthesis in radish. There are four color types of radish according to whether or not the anthocyanin accumulates in the skin and flesh of taproot. Red radishes accumulate a substantial amount of anthocyanins in both the skin and flesh. It is well known that the MYB-bHLH-WD40 transcription factor(s) complex regulates the biosynthesis of anthocyanin in plants. Here in, four candidate MYB and bHLH genes, RsMYB1a, RsMYB1b, RsbHLH2 and RsbHLH4, were isolated from red radish 'Hongxin 1'. The expression of RsbHLH4 and the two structural genes RsANS and RsUFGT was significantly positively correlated with anthocyanin contents. The expression of RsMYB1a was also highly correlated with anthocyanin accumulation, particularly when the white flesh sample of 'Hongxin 1-1' was excluded. The transient expression of RsMYB1a in the radish cotyledon and leaf induced anthocyanin accumulation with even stronger promoting role when expression in combination with RsbHLH4. These results suggested that RsMYB1a was the crucial MYB, and that RsbHLH4 is an essential partner in regulating the biosynthesis of anthocyanins in radish. The low or undetectable RsbHLH4 expression paralleled the lack of anthocyanin accumulation in the white flesh of 'Hongxin 1-1' and 'Shaguan 1'. Assays demonstrated that RsMYB1a interacted with RsbHLH4 and activated the expression of RsbHLH4. Notably, all the dark red radish cultivars have a longer RsMYB1a genomic DNA sequence, while the short and nonfunctional RsMYB1a is present in non-red cultivars. The length of the first intron and the presence of an early stop codon of RsMYB1 might underlie the differential anthocyanin accumulation in the radish taproot.

9.
PLoS One ; 14(11): e0225145, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31703099

RESUMO

USP14 is a cysteine protease deubiquitinase associated with the proteasome and plays important catalytic and allosteric roles in proteasomal degradation. USP14 inhibition has been considered a therapeutic strategy for accelerating degradation of aggregation-prone proteins in neurodegenerative diseases and for inhibiting proteasome function to induce apoptotic cell death in cancers. Here we studied the effects of USP14 inhibition in mammalian cells using small molecule inhibitors and an inactive USP14 mutant C114A. Neither the inhibitors nor USP14 C114A showed consistent or significant effects on the level of TDP-43, tau or α-synuclein in HEK293T cells. However, USP14 C114A led to a robust accumulation of ubiquitinated proteins, which were isolated by ubiquitin immunoprecipitation and identified by mass spectrometry. Among these proteins we confirmed that ubiquitinated ß-catenin accumulated in the cells expressing USP14 C114A with immunoblotting and immunoprecipitation experiments. The proteasome binding domain of USP14 C114A is required for its effect on ubiquitinated proteins. UCHL5 is the other cysteine protease deubiquitinase associated with the proteasome. Interestingly, the inactive mutant of UCHL5 C88A also caused an accumulation of ubiquitinated proteins in HEK293T cells but did not affect ß-catenin, demonstrating USP14 but not UCHL5 has a specific effect on ß-catenin. We used ubiquitin immunoprecipitation and mass spectrometry to identify the accumulated ubiquitinated proteins in UCHL5 C88A expressing cells which are mostly distinct from those identified in USP14 C114A expressing cells. Among the identified proteins are well established proteasome substrates and proteasome subunits. Besides ß-catenin, we also verified with immunoblotting that UCHL5 C88A inhibits its own deubiquitination and USP14 C114A inhibits deubiquitination of two proteasomal subunits PSMC1 and PSMD4. Together our data suggest that USP14 and UCHL5 can deubiquitinate distinct substrates at the proteasome and regulate the ubiquitination of the proteasome itself which is tightly linked to its function.

10.
Clin Neurol Neurosurg ; 187: 105567, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31704389

RESUMO

OBJECTIVES: The optimal treatment of symptomatic non-acute atherosclerotic intracranial large artery occlusion (ILAO) beyond 24 h from onset remains uncertain. We investigate the outcomes of late endovascular recanalization for symptomatic non-acute atherosclerotic ILAO. PATIENTS AND METHODS: From September 2013 to July 2018, with safety as the first principle, late endovascular recanalization for symptomatic non-acute atherosclerotic ILAO beyond 24 h from onset was attempted in 32 consecutive patients. Primary safety outcome was any stroke or death within 30 days. Primary efficacy outcome were functional independence at 90 days. RESULTS: The median time from imaging-documented occlusion to treatment was 25.5 days (interquartile range: 10.5-36.5) for all patients. Technical success in recanalization was achieved in 17 patients (53.1%, 17/32). The 30-day rate of any stroke or death was 5.9% (1/17) in the recanalized group versus 6.7% (1/15) in the failure group (P = 0.927). The rate of functional independence at 90 days (70.5%, 12/17) was increased significantly as compared with that before operation (23.5%, 4/17) in the recanalized group (P = 0.015). The rate of functional independence at 90 days (66.7%, 10/15) was not different from that before operation (66.7%,10/15) in the failure group (P = 1.00). The median score reduction in mRS from baseline at 90 days was 1.0 (interquartile range: 1.0-2.0) in the recanalized group versus 0 (interquartile range: 0.0-0.0) in the failure group (P<0.001). CONCLUSION: For carefully selected patients with symptomatic non-acute atherosclerotic ILAO beyond 24 h from onset, late endovascular recanalization is technically feasible. The periprocedural safety of late endovascular recanalization is acceptable. Successful recanalization may effectively improve the degree of disability in such patients. However, it should be emphasized that revascularization of non-acute ILAO is a high risk procedure, which should only be performed by experienced operators with safety as the first principle.

11.
J Biol Chem ; 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31676687

RESUMO

Inflamm-aging was recently affiliated with the progression of diabetic complications. Local cellular senescence together with senescence-associated secretory phenotype (SASP) are the main contributors to inflamm-aging. However, little is known about their involvement in diabetic periodontitis. Gingiva is the first line of host defense in the periodontium, and macrophages are key SASP-carrying cells. Here, we explored the molecular mechanism by which hyperglycemia drives the inflamm-aging in the gingival tissue of diabetic mice and macrophages. We demonstrated that hyperglycemia increased the infiltrated macrophage senescence in gingival tissue of diabetic mice. Simultaneously, hyperglycemia elevated the local burden of senescent cells in gingival tissue and induced the serum secretion of SASP factors in vivo. Moreover, in vitro, high glucose induced macrophage senescence and SASP factors secretion through phosphorylation of NLRC4, which further stimulated the NF-κB/Caspase-1 cascade via IRF8-dependent pathway. Deletion of NLRC4 or IRF8 abolished hyperglycemia-induced cellular senescence and SASP in macrophages. In addition, we found that treatment with metformin inhibited NLRC4 phosphorylation and remarkably decreased cellular senescence and SASP in the context of hyperglycemia. Our data demonstrated that hyperglycemia induces the development of inflamm-aging in gingival tissue and suggested that NLRC4 is a potential target for treatment of diabetes-associated complications.

12.
Opt Express ; 27(19): 26432-26445, 2019 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-31674525

RESUMO

Owing to the weak signals produced by all-fiber coherent lidar systems, when the instability of the local oscillator laser power is greater than the target echo signal, it is difficult to extract a target's intensity image. In this study, an intensity imaging method for weak signal all-fiber lidars is proposed. First, a phase compensation method is used to correct the position of the heterodyne signal in the time domain to reduce the impact of noise on the positioning heterodyne signal. In addition, an algorithm is proposed to extract the weak echo signal from the corrected heterodyne signal in the time domain to obtain the relative intensity of the echo signal of a single pixel point. Finally, we analyze and verify the proposed imaging method by using false alarm rates, range, intensity accuracy, and the speckle characteristics of the target. The method proposed in this study only requires that the phase of the heterodyne signal be corrected by the proposed numerical method without the need for other optical equipment, thus simplifying the entire system. It is very important to improve the detection sensitivity of coherent lidar remote imaging system.

13.
J Dairy Sci ; 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31677844

RESUMO

Previous research reported that fermented yak milk had a diverse microbial composition. For this study, raw yak milk, qula, and fermented yak milk samples were collected from the Aba Tibetan autonomous region of China. The genus and species microbial composition of these samples were analyzed by high-throughput sequencing of 16S rRNA and groEL gene amplicons, and the volatile profile of the samples was quantified by gas chromatography-mass spectrometry. The results indicated variation in abundance of microbiota at the genus level among the fermented yak milk samples, with Lactobacillus as the most abundant genus in the majority of samples, ranging from 41.6 to 98.26%. The volatile profile of the samples varied among those collected from different villages. Correlations between bacterial composition and volatile compounds of the samples were also observed. Lactobacillus displayed a significant correlation with volatile compounds such as benzaldehyde, 2,3-pentanedione, ethanol, and ethyl acetate, whereas the samples with relatively high abundance of Streptococcus and Lactococcus displayed relatively low contents of volatile compounds.

14.
J Pediatr Surg ; 2019 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-31679773

RESUMO

OBJECTIVE: Chylous ascites (CA) is a rare form of ascites that results from the leakage of lipid-rich lymph into the peritoneal cavity. In infants, CA is mostly caused by lymphatic malformation or unknown reasons. The creation of a shunt for the lymphorrhea is the last option for patients unresponsive to all other conservative treatments. Localization of the leakage is a critical problem during surgery. We applied a carbon nanoparticle suspension (CNS) in CA patients to locate the external lymphatic leakage and evaluated its utility during surgery. PATIENTS AND METHODS: Twelve infants with CA were treated in our center recently. Ten patients received laparotomy, one refused therapy, and one was cured after undergoing conservative treatment. Recently, two infants with CA received CNS in the visceral peritoneum during laparotomy. The results of the traditional procedure were compared to our innovative technique for CA to evaluate the use of CNS in treating CA. RESULTS: The features of the baseline data did not differ substantially. Location of the leakage with CNS was employed in 2 of the 10 patients whose lymphatic leakages were identified with the resolution of the refractory CA. Overall, in 5 patients, ascites was resolved successfully. The refractory CA was resolved more effectively in patients in whom the leakage site was identified with CNS than in patients in whom the leakage site could not be identified under conventional surgery. CONCLUSIONS: Injecting CNS improved the accuracy of lymphorrhagia leakage site identification and the outcomes of infants who underwent surgical treatment for refractory CA. LEVEL OF EVIDENCE: II-III.

15.
J Cell Biochem ; 2019 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-31680314

RESUMO

Circ-Foxo3 is a circRNA encoded by the human FOXO3 gene and works as a sponge for potential microRNAs (miRNAs) to regulate cancer progression. However, the role of circ-Foxo3 in esophageal squamous cell cancer (ESCC) is not clear. In this study, circ-Foxo3 was lowly expressed in cell lines and ESCC tissues. Meanwhile, overexpression of circ-Foxo3 inhibited cell growth, migration, and invasion, whether in vivo or in vitro. Mechanically, we found a potential miRNA target, miR-23a, which negatively correlated with circ-Foxo3 in ESCC. Then, a luciferase assay confirmed the relationship between the circ-Foxo3 and miRNA. Moreover, circ-Foxo3 upregulation of PTEN occurred through "sponging" miR-23a. Taken together, these results indicated that the circ-Foxo3/miR-23a/PTEN pathway was critical for inhibiting the ESCC progression. This may provide a promising target for treat ESCC.

16.
Anal Chim Acta ; 1092: 93-101, 2019 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-31708038

RESUMO

A novel homogeneous assay system QTR-FRET (Quencher modulated Time-Resolved Förster Resonance Energy Transfer) combining quenching resonance energy transfer (QRET) and time-resolved Förster resonance energy transfer (TR-FRET) was developed to reduce background signal in the conventional energy transfer applications. The TR-FRET functionality is often limited by the lanthanide donor background signal leading to the use of low donor concentration. QTR-FRET reduces this background by introducing soluble quencher molecule, and in this work the concept functionality was proven and compared to previously introduced QRET and TR-FRET technologies. Comparison was performed with three different Eu3+-chelates exhibiting different luminescent lifetime and stability. The side-by-side comparison of the three signaling systems and Eu3+-chelates was demonstrated in a model assay with Eu3+-chelate conjugated biotin and streptavidin (SA) or Cy5-SA conjugate. Comparison of the methodologies showed increased signal-to-background ratios when comparing QTR-FRET to TR-FRET, especially at high Eu3+-biotin concentrations. Quenching the non-bound Eu3+-biotin improved the assay performance, which suggests that an improved assay performance can be attained with the QTR-FRET method. QTR-FRET is expected to be especially useful for Eu3+-labeled ligands with low affinity or assays requiring high Eu3+-ligand concentration. The QTR-FRET indicated potential for multi-analyte approaches separately utilizing the direct QRET-type Eu3+-chelate signal and energy transfer signal readout in a single-well. This potential was hypothesized with Avi-KRAS nucleotide exchange assay as a second biologically relevant model system.

17.
J Gen Intern Med ; 2019 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-31713037

RESUMO

BACKGROUND: A clinical practice guideline (CPG) reporting checklist is used to assist CPG developers in recording what content should be provided in a CPG report. Recently, two checklists have become available on the Enhancing the QUAlity and Transparency Of health Research Network website: AGREE (Appraisal of Guidelines, Research and Evaluation) published in 2016 and RIGHT (Reporting Items for practice Guidelines in HealThcare) published in 2017. The objective of this study was to describe the advantages and disadvantages of these two CPG reporting checklists. METHODS: Two epidemiologists who lacked experience using both AGREE and RIGHT but were familiar with evidence-based medicine methodology independently compared AGREE with RIGHT on an item-by-item basis. Their assessments were compiled on a pre-designed data form and any disagreements were resolved through discussion. Three other co-authors independently compared AGREE with RIGHT and decided if they agreed with the results of comparison of the two CPG reporting checklists from the first two co-authors. Finally, another co-author reviewed the comparison results to ensure that the description was clear and understandable. RESULTS: The following six relationships between the two checklists were observed: (1) 11 items from AGREE completely matched with 12 items from RIGHT; (2) four items were listed in AGREE only; (3) 12 items were listed in RIGHT only; (4) three items in AGREE were partially covered by three items in RIGHT; (5) six items in RIGHT were partially covered by three items in AGREE; and (6) two items intersected across AGREE and RIGHT. Based on the comparison results, the potential impact analysis of selecting either checklist is described. DISCUSSION: We recommend that CPG developers use either AGREE plus items unique to RIGHT or RIGHT plus items unique to AGREE.

18.
Artigo em Inglês | MEDLINE | ID: mdl-31713615

RESUMO

OBJECTIVES: Carbapenem-resistant hypervirulent Klebsiella pneumoniae (CR-hvKP) have been increasingly reported in China. Here, a multicentre, longitudinal surveillance study on CR-hvKP is described. METHODS: We retrospectively investigated carbapenem-resistant K. pneumoniae (CRKP) in 56 centres across China during 2015-17 and screened the virulence genes (iucA, iroN, rmpA and rmpA2) for the presence of virulence plasmids. Hypermucoviscosity, serum killing and Galleria mellonella lethality experiments were conducted to identify CR-hvKP among strains with all four virulence genes. Capsule typing, fitness and plasmid features of CR-hvKP were also investigated. RESULTS: A total of 1052 CRKP were collected. Among these, 34.2% (360/1052) carried virulence genes and 72 of them had all four of the virulence genes tested. Fifty-five (76.4%) were considered to be CR-hvKP using the G. mellonella infection model, with KPC-2-producing K64-ST11 being the most common type (80%, 44/55). Prevalence of CR-hvKP differed greatly between regions, with the highest in Henan (25.4%, 17/67) and Shandong (25.8%, 25/97). A significant increase in CR-hvKP among KPC-2-producing ST11 strains was observed, from 2.1% (3/141) in 2015 to 7.0% (23/329) in 2017 (P = 0.045). Alarmingly, compared with classic CRKP, no difference in growth was found among CR-hvKP (P = 0.7028), suggesting a potential risk for dissemination. The hybrid virulence and resistance-encoding plasmid evolved from pLVPK and the resistance plasmid harbouring blaKPC-2, indicating evolution existed between the hypervirulence and hyper-resistance plasmid. CONCLUSIONS: CR-hvKP were more frequently detected than previously assumed, especially among KPC-2-producing ST11. Dissemination of hypervirulence could be extremely rapid due to limited fitness cost. Also, the evolution of resistance genes into hypervirulence plasmids was identified, presenting significant challenges for public health and infection control.

19.
Pest Manag Sci ; 2019 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-31714013

RESUMO

BACKGROUND: The Apolygus lucorum is one of the most destructive insect pests in China with a wide range of host plants. Interaction of A. lucorum with surrounding environments heavily relies on chemical communication. Deorphanization of receptors involved in odors detection elevates our understanding of the olfactory system of this pest and may help to develop a chemical ecology-based control strategy. RESULTS: AlucOR80, an odorant receptor in A. lucorum was newly cloned. Gene expression analysis showed that this receptor was mainly expressed in the antennae and head of both sexes but with a male bias. The Xenopus oocytes heterologous expression coupled with the two-electrode voltage-clamp system (TEVC) recordings revealed that AlucOR80 was tuned to 21 selected compounds. Furthermore, electroantennogram (EAG) tests confirmed that all 21 ligands of AlucOR80 were electrophysiologically active in antennae of both sexes. Behavioral trials in a three-cage olfactometer indicated that 16 compounds were behaviorally active, amongst which, 12 components were attractants and 4 components were repellents for adults of both sexes. Butyl butyrate and Dimethyl disulfide (DMDS) were the strongest attractive and repellant compounds, respectively. Importantly, we found the repellency of 1, 8-Cineole, S-(-)-cis-Verbenol and (1S)-(1)-beta-Pinene against adults of A. lucorum. CONCLUSION: Although AlucOR80 is a general odorant receptor, may play important roles in the olfactory perception of A. lucorum. Screening of AlucOR80 ligands by behavioral assay provided valuable insights and olfactory-based management approaches could be developed by utilizing the behaviorally active components as attractants or repellents. This article is protected by copyright. All rights reserved.

20.
BMC Oral Health ; 19(1): 236, 2019 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-31684930

RESUMO

BACKGROUND: Antiinflammatory effect of 1,25-dihydroxyvitamin D3 (1,25D3) has been reported in periodontitis, but the exact mechanisms remain unclear. Oral epithelial cells are recently highlighted as an important regulator of inflammation in this disease. This in vitro study was established to investigate the effect of 1,25D3 on key proinflammatory cytokine IL-6 production and aryl hydrocarbon receptor (AhR)/nuclear factor-κB (NF-κB) signaling in oral epithelial cells upon the stimulation of lipopolysaccharide (LPS) from periodontal pathogens. METHODS: OKF6/TERT-2 oral keratinocytes were incubated with LPS and different concentrations of 1,25D3, and levels of IL-6 production were determined using enzyme-linked immunosorbent assay (ELISA). Expression of vitamin D receptor (VDR), and activation of AhR was examined using western blot analysis, and phosphorylation of NF-κB was detected using cell-based protein phosphorylation ELISA. RESULTS: 1,25D3 inhibited LPS-induced IL-6 overexpression in OKF6/TERT-2 cells. Additionally, 1,25D3 increased VDR expression and AhR activation, and repressed NF-κB phosphorylation. Furthermore, 1,25D3 suppressed IL-6 expression and enhanced VDR expression and regulated AhR/NF-κB signaling activation in a dose-dependent manner after 48 h treatment. CONCLUSIONS: These results suggest that 1,25D3 may inhibit LPS-induced IL-6 overexpression in human oral epithelial cells through AhR/NF-κB signaling. Our findings may provide an explanation for the antiinflammatory effect and therapeutic benefit of 1,25D3 in periodontitis.

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