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1.
Pestic Biochem Physiol ; 163: 23-30, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31973862

RESUMO

Insecticidal Cry toxins produced by Bacillus thuringiensis (Bt) have been widely used to control agricultural pests in both foliage sprays and transgenic crops. Nevertheless, rapid evolution of insect resistance to Cry toxins requires elucidation of the molecular mechanisms involved in Cry resistance. Two proposed models have been described to explain the toxicity of Cry proteins, the classic model states that Cry protoxin is activated by midgut proteases resulting in activated toxin that binds to receptors and forms a pore in the midgut cells triggering larval death, and the newly proposed dual model of the mode of action of Bt Cry toxins states that protoxin and activated toxins may have different mechanisms of action since several resistant strains to activated Cry toxins are still susceptible to the same Cry-protoxin. Protoxin activation by midgut proteases is a key step in both models. Herein, we evaluated Cry1Ac protoxin activation in a susceptible Plutella xylostella (L.) strain (DBM1Ac-S) and in the near-isogenic strain (NIL-R) with high field-evolved Cry1Ac resistance. Previous work showed that Cry1Ac resistance in NIL-R correlates with reduced binding to midgut receptors due to enhanced MAPK signaling pathway and down regulation of ABCC2 receptor. However, reduced midgut trypsin levels and altered midgut protease gene transcription were also observed in the Cry1Ac-resistant field isolated strain that is parent of the NIL-R strain. Therefore, we analyzed the midgut protease activities in both DBM1Ac-S and NIL-R strains. Detection of enzymatic activities showed that caseinolytic protease, trypsin and chymotrypsin activities were not significantly different between the susceptible and resistant strains. Furthermore, treatment with different trypsin or chymotrypsin inhibitors, such as Nα-tosyl-l-lysine chloromethyl ketone (TLCK) or Np-tosyl-L-phenylalanine chloromethyl ketone (TPCK) did not affect the susceptibility to Cry1Ac protoxin of the DBM1Ac-S and NIL-R larvae. Bioassay results indicated that the NIL-R larvae showed similar resistant levels to both Cry1Ac protoxin and trypsin-activated toxin. Taken together, our results demonstrated that high-level field-evolved Cry1Ac resistance in the NIL-R strain is independent of Cry1Ac protoxin activation and the specific protoxin mechanism of action. This discovery will strengthen our comprehensive understanding of the complex mechanistic basis of Bt resistance in different insects.

2.
Carbohydr Polym ; 230: 115633, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31887911

RESUMO

The modification of starch owing to acid-thinning (AT) is intensified by a concomitant ultrasound (US) treatment, but the specific effect of the US on molecular changes, and the respective contribution of the single impacts are still unknown. The present study investigates the supporting effect of the US via examination and comparison of the single modifications [general conditions: starch slurry (40 % w/w), 40 °C, stirring; US: gradation of amplitude (50 and 100 %), cycle (0.50 and 0.75) and sonication time (20 and 60 min); AT: 0.36 M HCl, reaction time of 4 h] with the corresponding US assisted AT modified starches (US-AT) in terms of granular, molecular and functional properties. The US induced essentially a molecular degradation (debranching) of the amylopectin (AP), whereas chain cleavage within the amylose (AM) wasn't excluded completely. Altogether, the US was estimated to be a separate and assisting modification rather than an AT accelerating component.

3.
Carbohydr Polym ; 231: 115714, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31888845

RESUMO

Although supramolecular prodrug self-assemblies have been proven as efficient nanocarriers for cancer therapy, tedious synthesis procedures have made their practical applications more difficult. In this paper, ß-cyclodextrin-based supramolecular self-assemblies (SSAs) were directly constructed by utilizing ß-cyclodextrin trimer (ß-CD3) as the host unit and unmodified curcumin as the guest unit. Due to the adjustment of host-guest inclusion and hydrophilic-hydrophobic interactions occurring in the SSAs, their morphology could be readily tuned by changing the ratio of the two components. Different self-assembly morphologies, such as spherical complex micelles, spindle-like complex micelles and multi-compartment vesicles, were obtained. Furthermore, basic cell experiments were performed to study the corresponding effects of the SSA shape on their biological properties. Compared to the other micelles, the spindle-like complex micelles exhibited enhanced cellular toxicity, uptake behaviors and apoptosis rates, and the spherical complex micelles exhibited poor performance. The performance of the multi-compartment vesicles was similar to that of the spindle-like complex micelles. The facile construction of these shape-regulated SSAs and their different cellular biological properties might be valuable in the controlled drug release field.

4.
Artigo em Inglês | MEDLINE | ID: mdl-31957946

RESUMO

Lead halide perovskites have attracted tremendous attention to find their promising potential in various applications as optoelectronics. Unfortunately, this materials with mixed cations/anions often suffer from phase segregation, which is detrimental to the device efficiency and long-term stability. During perovskite film growth, the gel stage (in between liquid and crystalline) correlates to the phase segregation, which has been rarely explored. Herein, we systematically investigate the cation diffusion kinetics at the gel stage to develop a diffusion model obeying Fick's Second Law. Take 2D layered perovskite as an example, we combine theoretical and experimental results to reveal the impacts of diffusion coefficient, temperature, and gel duration on the film growth and phase formation. In light of this finding, we successfully fabricate a homogenous 2D perovskite thin film without significant phase segregation. This in-depth understanding of gel stage and relevant cation diffusion kinetics would further guide the design and processing of halide perovskites with mixed composition to meet requirements for optoelectronic applications.

5.
J Aging Phys Act ; : 1-7, 2020 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-31918405

RESUMO

Changes in body composition are related to mobility, fall risk, and mortality, especially in older adults. Various devices and methods exist to measure body composition, but bioelectrical impedance analysis (BIA) has several advantages. The purpose of this study was to validate a common BIA device with a dual-energy X-ray absorptiometer (DXA) in older adults and develop prediction equations to improve the accuracy of the BIA measurements. The participants were 277 older adults (162 women and 115 men; age 73.9 ± 5.8 years) without a history of cancer and without a history of severe medical or mental conditions. Individuals fasted 12 hr before BIA and DXA measurement. The correlations between the two methods for appendicular lean mass (ALM), fat-free mass (FFM), and percentage body fat (%BF) were .86, .93, and .92, respectively, adjusting for age and sex. The mean percentage error (DXA-InBody) and mean absolute percentage error were -12% and 13% for ALM, -13% and 13% for FFM, and 16% and 17% for %BF. The prediction equations estimated ALM, FFM, and %BF; sex was coded as 1 for male and 0 for female: DXAALM=0.0673+(0.6732×BIAALM)+(2.33507×sex)+(0.13349×BMI),R2=.94; DXAFFM=0.72323+(0.72384×BIAFFM)+(3.675012×sex)+(0.2816×BMI),R2=.97; and DXA%BF=15.8896+(0.64694×BIA%BF) -(3.99945×sex)+(0.13824×BMI),R2=.91 Although highly correlated, BIA overestimated FFM, and ALM and underestimated %BF compared with DXA. An application of prediction equations eliminated the mean error and reduced the range of individual error across the sample. Prediction equations may improve BIA accuracy sufficiently to substitute for DXA in some cases.

6.
Neuroscience ; 2020 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-31917345

RESUMO

Enkephalin (ENK) has been implicated in pain modulation within the spinal dorsal horn (SDH). Revealing the mechanisms underlying ENK analgesia entails the anatomical and functional knowledge of spinal ENK-ergic circuits. Herein, we combined morphological and electrophysiological studies to unravel local ENK-ergic circuitry within the SDH. First, the distribution pattern of spinal ENK-ergic neurons was observed in adult preproenkephalin (PPE)-GFP knock-in mice. Next, the retrograde tracer tetramethylrhodamine (TMR) or horseradish peroxidase (HRP) was injected into the parabrachial nucleus (PBN) in PPE-GFP mice. Immunofluorescent staining showed I-isolectin B4 (IB4) labeled non-peptidergic afferents were in close apposition to TMR-labeled PBN-projecting neurons within lamina I as well as PPE-immunoreactivity (-ir) neurons within lamina II. Some TMR-labeled neurons were simultaneously in close association with both IB4 and PPE-ir terminals. Synaptic connections of these components were further confirmed by electron microscopy. Finally, TMR was injected into the PBN in adult C57BL/6 mice. Whole-cell patch recordings showed that δ-opioid receptor (DOR) agonist, [D-Pen2,5]-enkephalin (DPDPE, 1 µM), significantly reduced the frequency of miniature excitatory postsynaptic current (mEPSC) and decreased the activity of TMR-labeled neurons. In conclusion, spinal ENKergic neurons receive direct excitatory inputs from primary afferents, which might be directly recruited to release ENK under the condition of noxious stimuli; ENK could inhibit the glutamatergic transmission towards projecting neurons via presynaptic and postsynaptic DORs. These morphological and functional evidence may explain the mechanisms underlying the analgesic effects exerted by ENK within the SDH.

7.
Pest Manag Sci ; 76(2): 712-720, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31359575

RESUMO

BACKGROUND: Rapid evolution of pest resistance has seriously threatened the sustainable use of Bacillus thuringiensis (Bt). The diamondback moth, Plutella xylostella (L.), is the first pest to develop resistance to Bt biopesticides in the open field, which renders it an excellent model to explore the molecular basis of Bt resistance in insects. Our previous midgut transcriptome and RNA-Seq profiles showed that the P-glycoprotein gene PxABCB1 was down-regulated in two Cry1Ac-resistant P. xylostella strains, suggesting its potential involvement in Cry1Ac resistance in P. xylostella. RESULTS: In this study, the bona fide full-length cDNA sequence of the PxABCB1 gene was cloned and analyzed, and the expression of the PxABCB1 gene was detected in all tissues and developmental stages, with the highest expression in midgut tissue and the female adult stage. Although no consistent non-synonymous mutations were identified between the susceptible and resistant strains, PxABCB1 gene expression was remarkably decreased in all resistant strains, and the association was further validated by Cry1Ac selection in the moderately resistant SZ-R strain. Moreover, knockdown of the PxABCB1 gene expression resulted in significantly reduced larval susceptibility to Cry1Ac toxin in the DBM1Ac-S strain, and decreased expression of the PxABCB1 gene was tightly linked to Cry1Ac resistance in P. xylostella. CONCLUSION: Our results demonstrated that down-regulation of the PxABCB1 gene is associated with both laboratory-selected and field-evolved Cry1Ac resistance in P. xylostella. This knowledge will be conducive to further elucidating the complicated molecular basis of Bt resistance and developing new insect resistance management tactics. © 2019 Society of Chemical Industry.

8.
Int J Oncol ; 56(1): 301-314, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31746425

RESUMO

Epithelial ovarian cancer is aggressive and lacks effective prognostic indicators or therapeutic targets. In the present study, using immunohistochemistry and bioinformatics analysis on ovarian cancer tissue data from The Obstetrics and Gynecology Hospital of Fudan University and The Cancer Genome Atlas database, it was identified that FXYD domain­containing ion transport regulator 5 (FXYD5) expression was upregulated in the SKOV3­IP cell line compared with its parental cell line, SKOV3, and in ovarian cancer tissues compared with in normal tissues. In addition, FXYD5 upregulation was predictive of poor patient survival. Furthermore, through various in vitro (Transwell assay, clonogenic assay and western blot analysis) and in vivo (nude mouse model) experiments, it was demonstrated that FXYD5 promoted the metastasis of ovarian cancer cells. Mechanistically, RNA sequencing, western blot analysis, a luciferase reporter assay and chromatin immunoprecipitation were performed to reveal that FXYD5 dispersed the SMAD7­SMAD specific E3 ubiquitin protein ligase 2­TGF­ß receptor 1 (TßR1) complex, deubiquitinated and stabilized TßR1, and subsequently enhanced transforming growth factor­ß (TGF­ß) signaling and sustained TGF­ß­driven epithelial­mesenchymal transition (EMT). The TGF­ß­activated SMAD3/SMAD4 complex was in turn directly recruited to the FXYD5 promoter region, interacted with specific SMAD­binding elements, and then promoted FXYD5 transcription. In brief, FXYD5 positively regulated TGF­ß/SMADs signaling activities, which in turn induced FXYD5 expression, creating a positive feedback loop to drive EMT in the process of ovarian cancer progression. Collectively, the findings of the present study suggested a mechanism through which FXYD5 serves a critical role in the constitutive activation of the TGF­ß/SMADs signaling pathways in ovarian cancer, and provided a promising therapeutic target for human ovarian cancer.

9.
Artigo em Inglês | MEDLINE | ID: mdl-31809961

RESUMO

Individualized therapy involves genetic test of drug metabolism, which provides information about the initial dose and therapeutic drug monitoring for adjusting the subsequent dose. Consequently, toxic side effects are expected to be minimized and therapeutic effects to be maximized. In this study, an ultra-performance liquid chromatography tandem mass spectrometry method that was specific, accurate and sensitive was developed to simultaneously determine azathioprine two metabolites, 6-thioguanine nucleotides (6-TGN) and 6-methyl-mercaptopurine riboside (6-MMPr) in the whole blood lysate. We precipitated the sample by trifluoroacetic acid under the protection of dithiothreitol, with 6-MMPr and 6-TGN being hydrolyzed to produce 6-methymercaptopurine and 6-thioguanine. In the chromatographic separation, Waters ACQUITY BEH C18 (2.1 × 100 mm, 1.7 µm) chromatographic column was applied and gradient elution was conducted with 0.02 mol/L ammonium acetate buffer (which contains 0.3% formic acid) and acetonitrile at a flow rate of 0.4 ml/min. Tandem mass spectrometry in multiple reaction monitoring mode was applied for detection via electrospray ionization source in positive ionization mode. The analyzing process lasted for no more than 2 min. The calibration curve for each metabolite fitted a least squares model (weighed 1/X) from 1.25 to 5000 ng/ml (r2 > 0.99). The ion pairs were detected as 6-MMP m/z 167.07 â†’ 152.15, 6-TG m/z 168.06 â†’ 134.13, and internal standard m/z 171.07 â†’ 137.14. Under the guidance of FDA guidelines for bioanalytical method validation, we carried out validation and obtained satisfactory results. The method was successfully utilized for monitoring the concentrations of each metabolite from 65 affected patients who had received azathioprine maintenance therapy and achieved optimal results.

10.
ACS Appl Mater Interfaces ; 12(2): 3127-3133, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31833753

RESUMO

Two-dimensional (2D) lead halide perovskite has recently been recognized as a promising candidate to stabilize perovskite solar cells due to its extraordinary moisture resistance. These 2D perovskite films often consist of multiple phases with layered (n) lead halide (from n = 1, 2, 3 to ≈∞). However, a convincing evidence is still lacking to clarify the phase distribution with respect to different n, thus causes the misleading for device design. Herein, confocal photoluminescence (PL) spectroscopy was applied to probe the inhomogeneity of 2D perovskite films along the vertical direction to construct a clear-phase distribution mapping consequently. It reveals that the 2D perovskite phases (n = 2, 3, 4) locate preferentially near the substrate, while large n phases are predominantly near the top surface. Moreover, we successfully developed a simple method to manipulate the phase distribution in 2D perovskite thin films, which results in a dramatic increase of device efficiency from 4.95 to 11.6%. Our findings thus provide insights to the understanding of 2D perovskite film growth. The utilization of visualized phase distribution data could also guide the further development of 2D perovskite materials for optoelectronic devices.

12.
Int J Nurs Stud ; 101: 103397, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31683227

RESUMO

OBJECTIVES: Ensuring that the first-degree relatives of patients with colorectal cancer are properly screened is critical to reduce disease incidence and mortality rate. Tailored communication intervention is a promising method to induce health-related behavioural changes. However, evidence of the effects of tailored communication interventions on the screening rate of populations at an increased familial risk of colorectal cancer is lacking. This review aimed to identify, appraise and examine existing evidence of the effectiveness of tailored communication interventions in increasing colonoscopy screening rates amongst the first-degree relatives of people with colorectal cancer. DESIGN: Systematic review and meta-analysis. DATA SOURCES: Twelve electronic English and Chinese databases [Medline, EMBASE, PubMed, Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Review, CINAHL, Scopus, Global Health, British Journal Index, China National Knowledge Infrastructure (CNKI), Wan Fang Data and China Biology Medicine (CBM)] were searched to identify eligible clinical trials that were published over period of 1995 to October 2018. REVIEW METHODS: Studies were selected by using key words, such as 'colorectal cancer', 'screening', 'colonoscop*', 'first degree relative*', 'uptake or adhere*' and 'cost'. Two reviewers independently assessed the eligibility of each study and extracted the data. The Cochrane Risk of Bias Tool was applied to evaluate the risk of bias amongst included studies. Meta-analysis was performed when possible. Subgroup analysis was performed for types of communication channels. Sensitivity analysis was conducted to explore the influence of random units on the primary outcome. RESULTS: Four studies that adopted tailored communication interventions to increase colonoscopy screening rates were identified. Pooled analysis showed that tailored communication had a beneficial effect on improving colonoscopy use in the colorectal cancer screening context (OR: 2.21, 95% CI: 1.71-2.85, p < 0.01). Furthermore, subgroup analysis showed that repeated tailored communication delivered via print plus telephone call had a significant effect on increasing colonoscopy screening rates (OR: 2.39, 95% CI: 1.78-3.21, p < 0.01). The results of sensitivity analysis indicated that types of randomisation units did not influence outcomes. CONCLUSION: Tailored communication is a beneficial approach for increasing colonoscopy screening rates amongst first-degree relatives who are at increased familial risk of colorectal cancer. The effective components of tailored communication were repeated contacts, combined verbal and written communication and important tailored variables. Future studies with rigorous designs are recommended to develop an integrated tailoring assessment decision system with the support of Internet-based communication channels.

13.
ACS Nano ; 13(12): 14426-14436, 2019 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-31799834

RESUMO

As the cleaners of cells, lysosomes play an important role in circulating organic matter within cells, recovering damaged organelles, and removing waste via endocytosis. Because lysosome dysfunction is associated with various diseases-lysosomal storage diseases, inherited diseases, rheumatoid arthritis, and even shock-it is vital to monitor the movement of lysosomes in cells and in vivo. To that purpose, a method of optical imaging, super-resolution imaging technology (e.g., SIM and STORM), can overcome the limitations of traditional optical imaging and afford a range of possibilities for fluorescence imaging. However, the short wavelength excitation and easy photobleaching of super-resolution fluorescence probes somewhat problematize super-resolution imaging. As described herein, we designed a low-toxicity, photostable, near-infrared small molecule fluorescence probe HD-Br for use in the super-resolution imaging of lysosomes. The interaction of lysosomes and mitochondria was dynamically traced while using the probe's properties to label the lysosomes. Because the probe has the optimal near-infrared excitation and emission wavelengths, liver organoid 3D imaging and Caenorhabditis elegans imaging were also performed. Altogether, our findings indicate valuable approaches and techniques for super-resolution 3D and in vivo imaging.

14.
Eur J Protistol ; 72: 125659, 2019 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-31825791

RESUMO

Three species of tintinnines, namely Tintinnopsis tentaculata Nie and Cheng, 1947, Tintinnopsis orientalis Kofoid and Campbell, 1929, and Eutintinnus lususundae (Entz, 1885) Kofoid and Campbell, 1939, were isolated from coastal waters of China. The morphology of each was investigated based on observations of live and protargol-stained specimens, and their SSU rDNA- and LSU rDNA-based phylogenetic relationships were analyzed. The ciliary patterns of these species are revealed for the first time. Based on the original descriptions and data from the present study, an improved diagnosis is given for each species. Unlike its congeners, the second dorsal kinety of Eutintinnus lususundae is displaced below the left ciliary field, which may suggest that the second dorsal kinety is evolving into a posterior kinety by a migration process. The ventral kinety in Eutintinnus is redefined. A neotype is fixed for T. tentaculata to stabilize the species name objectively, mainly because of the unavailability of type material.

15.
Materials (Basel) ; 12(23)2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31805649

RESUMO

Solid porous materials, like zeolites, have been widely used in a variety of fields such as size-and-shape-selective absorption/separation and catalysis because of their porosity. However, there are few liquid materials that exhibit permanent porosity. Porous liquids are a novel material that combine the properties of fluidity and permanent porosity. They have potential applications in many fields such as gas separation, storage and transport. Herein, we report a novel Type 1 porous liquid prepared based on silicalite-1. The pore size of this porous liquid was determined by positron annihilation lifetime spectroscopy (PALS), and the CO2 capacities were determined by the intelligent gravimetric analyzer (IGA). The unique properties of this porous liquid can promote its application in many fields such as gas storage and transport.

16.
Ying Yong Sheng Tai Xue Bao ; 30(11): 3804-3810, 2019 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-31833694

RESUMO

Pot experiment with winter wheat was conducted to investigate the effects of blended nitrogen (N) fertilizer (slow-release fertilizer-N:urea-N=1:1) combined with N fertilizer inhibitor NAM on soil ammonium (NH4+-N), nitrate (NO3--N), microbial biomass nitrogen (MBN) and fixed-ammonium (FN) contents. We analyzed dynamic characteristics of soil mineral N, MBN, FN pools under different treatments. There were six treatments, including no N fertilizer (CK), conventional urea (U), blended N fertilizer (MU), MU plus 2.5‰ NAM (MUN1), MU plus 5‰ NAM (MUN2), and MU plus 7.5‰ NAM (MUN3). Our results showed that, compared to that of MU treatment, MUN2 and MUN3 delayed the appearance time of NH4+-N peak. Averaged across the whole wheat growing period, soil mineral N content for NAM treatments decreased by 5.3%-11.7%. From tillering to maturity stage, MBN mineralization and mineralization rates were 38.96 mg·kg-1 and 91.5%, which was higher than that of U treatment; MBN mineralization and mineralization rates for MUN1, MUN2 and MUN3 treatments were 58.73 mg·kg-1, 83.3%, 94.20 mg·kg-1, 94.6%, 104.46 mg·kg-1 and 96.3%, respectively. The FA mineralization release for NAM treatments were higher by 2.83-9.19 mg·kg-1 than that of MU treatment. The results of path analysis showed that NAM addition weakened the direct effect of soil NH4+-N pool on NO3--N pool but enhanced the indirect effects of FN pool on NO3--N pool through affecting NH4+-N pool. The wheat grain yields of the MUN1, MUN2 and MUN3 treatments were significantly higher by 31.6%, 21.5% and 22.9% than that of MU treatment. Nitrogen use efficiencies were increased by 8.1%, 13.5% and 3.1%, respectively. In summary, through double regulation for N release and transformation in soil, NAM delayed the appearance time of soil NH4+-N peak and retarded its transformation into NO3--N, and increased the roles of MBN and FN in supplying N, thereby increased crop yield and N-fertilizer use efficiency.


Assuntos
Fertilizantes , Solo , Agricultura , Nitratos , Nitrogênio , Triticum
17.
Int J Cardiol ; 2019 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-31884007

RESUMO

BACKGROUND: Spontaneous coronary artery dissection (SCAD) has emerged as an important etiology of myocardial infarction and sudden death, especially in young women. Early diagnosis is essential for appropriate management. OBJECTIVES: To explore the value of plasma fibrillin-1 (FBN1) levels in patients with SCAD. METHODS: 70 patients with non-atherosclerotic SCAD between January 2014 and September 2018 were age and sex matched with 70 patients with non-SCAD acute coronary syndrome (ACS) and 70 healthy controls. The plasma FBN1 level was measured and compared among three groups. The value of FBN1 for prognosis and treatment decision making was further explored. RESULTS: The plasma FBN1 level of SCAD group (58.44 ± 7.06 ng/mL) was higher than that of non-SCAD ACS group (52.39 ± 6.92 ng/mL, P < 0.001) or healthy controls (50.56 ± 4.48 ng/mL, P < 0.001). Compared with controls, significantly higher percentages of patients with SCAD were found in the highest compared with lowest quartile of FBN1 concentration. The area under the curve (AUC) for plasma FBN1 level to discriminate patients with SCAD from non-SCAD ACS was 0.81 (95% CI 0.74-0.88, P < 0.001). A cut-off value of 54.64 ng/mL was determined to differentiate SCAD from non-SCAD ACS with a sensitivity of 0.77 (95%CI: 0.66-0.86) and specificity of 0.76 (95%CI: 0.64-0.85). After a median follow-up of 28.35 (14.07 ± 44.69) months, 11 (15.7%) cases suffered from major adverse cardiac events (MACE). Higher FBN1 level was detected in patients with MACE (63.71 ± 7.49 vs. 57.45 ± 6.58 ng/mL) (P = 0.006). A cut-point of 58.14 was determined for SCAD patients to identify MACE. At this point, FBN1 might also have potential use for decision making in SCAD patients. CONCLUSION: Plasma FBN1 is a promising biomarker for aiding the diagnosis of SCAD and have potential value in prognosis prediction.

18.
Radiat Res ; 2019 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-31841081

RESUMO

The goal of this work was to elucidate the mechanisms of bystander effects outside the localized irradiation field and their potential hematological toxicity. In this study, an in vitro multicellular co-culture system was used to investigate the intercellular commutation and related signaling pathways between either irradiated A549 cells or Beas-2B cells and bystander lymphoblast TK6 cells with or without macrophage U937 cells as an intermediator. Results showed that the proliferation ability of bystander TK6 cells was inhibited after co-culture with A549 cells irradiated with γ rays rather than carbon ions. When macrophages were contained in the co-culture system, the cell viability damage to the bystander TK6 cells were further enhanced. However, the proliferation inhibition of bystander TK6 cells after co-culture with irradiated Beas-2B cells was observed only when intermediator macrophages existed in the cell co-culture system. More serious cell injury was detected after carbon-ion irradiation compared with γ-ray irradiation. The p53-relevant apoptosis pathway was activated in both irradiated A549 and Beas-2B cells, each to a different extent. When the p53 pathway of irradiated cells was inhibited by PFT-α, PFT-µ or p53 siRNA, the bystander damage to TK6 cells were clearly alleviated. In conclusion, the bystander lymphoblast damage was induced in different cells using different LET radiations. An amplified bystander response was modulated by the intermediator macrophage. The underlying molecular mechanisms of these bystander effects were dependent on the activation of p53 and its relevant apoptosis pathway in the irradiated cells. These results suggest that the bystander and macrophage-mediated bystander effects contribute to the common acute side effect of lymphocytopenia after local irradiation.

19.
Int J Neurosci ; : 1-9, 2019 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-31847650

RESUMO

Objective: Spinal cord stimulation (SCS) is a valuable treatment for patients with disorders of consciousness (DOC). This study used permutation entropy (PeEn) of neural activities to quantify brain responses to SCS.Method: We recruited 14 patients with DOC, including seven patients in minimally conscious state (MCS) and seven patients in vegetative state/unawareness state (VS/UWS). All patients received a single session of 20 min' continuous SCS. We recorded resting state EEG before, during and after SCS. In this study, PeEn was first calculated to describe overall neural activities changes in SCS. The brain was then divided into frontal, central, parietal and occipital regions to explore spatial SCS modulation effects. Finally, a correlation analysis was conducted between CRS-R values and changes in PeEn on each of the four regions.Results: SCS was associated with short-term changes in neural activities in DOC. When SCS was on, PeEn increased as compared to the baseline. When SCS was shut off, PeEn decreased. The PeEn of all patients after SCS was higher than before SCS, and changes of PeEn for MCS were more significant than those for VS, especially in the frontal region.Conclusion: PeEn from EEG data could be used to evaluate SCS modulation effects, and EEG complexity might be a critical index to describe brain responses to SCS in DOC.

20.
Anal Chem ; 91(23): 14936-14942, 2019 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-31670502

RESUMO

Förster resonance energy transfer (FRET) is a well-established method for studying macromolecular interactions and conformational changes within proteins. Such a method normally uses fluorescent proteins or chemical-labeling methods which are often only accessible to surface-exposed residues and risk-disturbing target protein structures. Here, we demonstrate that the genetic incorporation of a synthetic fluorescent amino acid, L-(7-hydroxycoumarin-4-yl) ethylglycine (Cou) and natural endogenous fluorophore Tryptophan (Trp) residues of a protein could serve as an efficient FRET pair to monitor protein interactions, using the signaling transducer ß-arrestin-1 as a model system. We used this technology to record the dynamic spectra in both binding and competition experiments of ß-arrestin-1, the contribution of each specific phosphate in ternary complex formation, in a rapid and efficient manner. The determined Kd value for the association between the active arrestin and Fab30 is 0.68 µM in the three-component interaction system. Moreover, we were able to determine the contributions of the site 3 phospho-site and the site 6 phospho-site binding, each contributing to the high affinity ternary complex assembly as 2.7 fold and 15.5 fold, respectively, which were never determined before. These results thus highlighted the potential usage of this new method in measurement of the allosteric-induced enhanced affinity with small amount proteins and in a fast manner and in a complex system. Collectively, our newly developed Trp:Cou FRET system based on genetic expansion technology has extended the molecular toolboxes available for biochemical and structural biology studies.

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