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1.
Infect Dis Poverty ; 9(1): 13, 2020 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-32005290

RESUMO

BACKGROUND: China is facing challenges of the shifting presentation of tuberculosis (TB) from younger to elderly due to an ageing population, longer life expectancy and reactivation disease. However, the burden of elderly TB and influence factors are not yet clear. To fill the gap, we generated a cohort study to measure the magnitude of TB incidence and associated factors among the elderly population aged 65 years and above in China. METHODS: In this cohort established in 2013 through a prevalence survey conducted in selected sites, a total of 34 076 elderlies without TB were enrolled into two-year follow-up. We used both active and passive case findings to find out all TB patients among them. The person-year (PY) incidence rates for both bacteriologically positive TB and active TB were calculated. Cox proportional regression model was performed to test effect of risk factors, and the population attributable fraction (PAF) of each risk factor contributing to incident TB among elderlies was calculated. RESULTS: Over the two-year follow-up period, a total of 215 incident active TB were identified, 62 of which were bacteriologically positive. The incidence rates for active TB and bacteriologically positive TB were 481.8 per 100 000 PY (95% CI: 417.4-546.2 per 100 000 PY) and 138.9 per 100 000 PY (95% CI: 104.4-173.5 per 100 000 PY), respectively. Incident cases detected by active case finding were significantly higher (P < 0.001). Male, non-Han nationality, previously treated TB, ex/current smoker and body mass index (BMI) < 18.5 presented as independent predictors for developing TB disease. For developing bacteriologically positive TB, the biggest contribution was from self-reported ex or current smoker (18.06%). And, for developing active TB, the biggest contribution was from non-Han nationality (35.40%), followed by male (26.80%) and age at 75 years and above (10.85%). CONCLUSIONS: Ageing population in China had a high TB incidence rate and risk to develop TB disease, implying that National TB Program (NTP) needs to prioritize for elderly. Active case finding should be applied capture more active TB cases among this particular population, especially for male, non-Han nationality, and those with identified risk factors.

2.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 28(1): 307-313, 2020 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-32027294

RESUMO

OBJECTIVE: To analyze the clinical characteristics, pathological features, treatment response and prognosis of patients with blastic plasmacytoid dendritic cell neoplasm (BPDCN), so as to provide reference for reducing clinical misdiagnosis and treatment regimens. METHODS: The clinical, pathological features, treatment regimens and treatment response of 9 patients with BPDCN diagnosed and treated from January 1, 2013 to June 30,2019 in Xiangya Second Hospital of Central South University were analyzed respectively. RESULTS: The most common site of involvement in 9 patients with BPDCN was skin; the pathological features were involvement of dermis, and the highest positive immunohistochemical indexes rate were CD4, CD43, LCA, CD123, and VIM (all 100%), followed by CD56 and CD68, TDT, CD5, PAX-5, CD3, CD8, CD20; MPO and EBER of 9 patients were negative. However, Ki-67 of the 9 patients showed a medican of 77. 5% (40%-90%), which suggests that CD4, CD43, LCA, CD123, and VIM were the most sensitive antigens for diagnosing BPDCN. Of the 9 patients, 2 cases were lost to follow-up, 2 cases were untreated, and 5 cases were treated, in which 2 cases received treatment of regiment for acute lymphoblastic leukemia and 3 cases received treatment of regimen for lymphoma. The PR of clinical symptoms in the first cycle in 5 patients were 100%, and 1 patient has survived for 6 years since the disease was diagnosed. CONCLUSION: BPDCN is a rare and highly invasive lymphoid hematopoietic malignancy. The most common initial symptom of the patients is skin lesions. The most sensitive pathological indicators are CD4, CD43, LCA, VIM, and the BPDCN patients received treatment of regimens for lymphoid tumor show a better response rate.

3.
Environ Technol ; : 1-14, 2020 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-32003648

RESUMO

A novel magnetic Fe3O4@chitosan@taurine adsorbent (MCT) was prepared by surface modification of magnetic chitosan nano-composites with taurine-glutaraldehyde solution. The adsorbents were characterized by FTIR, SEM, TEM, XRD, TGA and VSM techniques, respectively. According to the FTIR spectrum of MCT, the characteristic peaks of the SO3-group on MCT were observed to have a shift after adsorption of the cationic dye, which indicates that there may be electrostatic attraction between the MCT and the cationic dye. Moreover, the saturation magnetization of MCT was found to be 20.797 emu g-1, suggesting that MCT has sufficient magnetic response to meet the need of magnetic separation. The adsorption properties of cationic dyes by MCT were further investigated by using methylene blue (MB) as a representative. The adsorption behaviour of MB by MCT was well described by the pseudo-second order kinetic model and the Langmuir isotherm model, respectively. The maximum adsorption capacity of MB calculated from the Langmuir model fitting was 204.1 mg g-1 at pH 5 and 384.6 mg g-1 at pH 9, respectively, and the adsorption equilibrium could be reached within 10 min. Besides, the negative values of ΔG° and ΔH° suggested that the adsorption process was spontaneous and exothermic, and the good reusability indicated that MCT could act as a recyclable adsorbent for dye adsorption. All of these results illustrate that MCT has great potential for practical application in removal of cationic dyes from aqueous solutions.

4.
BJOG ; 2020 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-32009280

RESUMO

OBJECTIVE: To establish the age-specific centiles of serum AMH levels in Chinese women, and to explore the use of multiples of median (MOM) AMH levels for the diagnosis of polycystic ovary syndrome (PCOS). DESIGN: An observational study SETTING: University-affiliated hospitals and community clinics POPULATION: We included 3137 healthy women aged 20-44 years recruited prospectively or who had archived serum samples from previous research projects. Another validation cohort of 751 women with PCOS as well as ovulatory controls, which was a convenient sample of women attending for infertility or menstrual disorders, was also studied. METHODS: The serum samples were assayed for AMH by the automated Access AMH assay. MAIN OUTCOME MEASURES: Age-specific reference ranges were constructed on the primary cohort with the Lambda-Mu-Sigma method. The MOM AMH of each subject in the validation cohort was calculated. RESULTS: Centile curves of serum AMH level against age were established. MOM AMH was significantly higher in women with PCOS compared to controls (p<0.05). The area under the ROC curve was 0.852 (95% CI 0.825-0.877) (p<0.0001) for discriminating women with PCOS from ovulatory controls by MOM AMH. CONCLUSIONS: We established a set of year-by-year age-specific reference ranges of serum AMH levels in Chinese women, and the MOM AMH derived from this set of reference ranges is a promising tool to replace antral follicle count in the diagnosis of PCOS.

5.
Carbohydr Polym ; 231: 115699, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31888847

RESUMO

Herein, six ionic liquids (ILs) with different cations and the same anion of acetate (Ac-) were used to dissolve arabinoxylan. These ILs included N-methylimidazolium acetate (HmimAc), 1-ethyl-3-methylimidazolium acetate (EmimAc), 1-hydroxyethyl-3-methylimidazolium acetate (HOemimAc), 1-propyl-3-methylimidazolium acetate (PrmimAc), 1-allyl-3-methylimidazolium acetate (AmimAc), and 1-butyl-3-methylimidazolium acetate (BmimAc). The solubilities of arabinoxylan in these ILs were determined, and the dissolution mechanism was explained using 1H and 13C NMR techniques. The solubilities of arabinoxylan in the ILs were in the order: BmimAc > EmimAc > AmimAc > PrmimAc > HOemimAc > HmimAc. Both the cation and Ac- played an important role in the solubilization of arabinoxylan, but Ac- performed the major factor. The structure of cation greatly affected the hydrogen bond accepting ability of Ac-. Increasing the mass ratio of arabinoxylan to ILs resulted in stronger hydrogen bond between arabinoxylan and the ILs. Both the solubility and the strength of hydrogen-bonding interaction between arabinoxylan and the ILs decreased in the recycled ILs because of the impurities remained.

6.
J Mater Chem B ; 8(5): 1033-1039, 2020 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-31939981

RESUMO

Photothermal therapy following microscopic temperature detection can avoid overheating effects or insufficient heating, and thus improve therapeutic efficacy. In this study, biocompatible dual-functional nanoparticles (NPs) are constructed from polypyrrole (PPy) and rhodamine B (RB) by a one-step modified polymerization method. The polypyrrole serves as a photothemal agent, and rhodamine B acts as a temperature-sensing probe. The polypyrrole-rhodamine B (PPy-RB) NPs possess a high photothermal effect on irradiation by 808 nm laser, and a competent temperature sensitivity for the real-time temperature monitoring based on the emission intensity response of rhodamine B. After acting on HepG2 cells, the PPy-RB NPs can effectively induce cancer cell death, and the microscopic temperature is monitored by fluorescence feedback from rhodamine B during PTT by laser confocal microscopy. Hence, the proposed approach can supply a facile and promising way for the fabrication of effective theranostic nanoplatforms assisted by self-monitoring of cancer therapeutic processes.

7.
Cancer Imaging ; 20(1): 9, 2020 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-31969196

RESUMO

BACKGROUND: There is a growing need for a reproducible and effective imaging method for the quantitative differentiation of benign from malignant thyroid nodules. This study aimed to investigate the performances of intravoxel incoherent motion (IVIM) parameters and the apparent diffusion coefficient (ADC) in differentiating malignant from benign thyroid nodules derived from the most repeatable region of interest (ROI) delineation. METHODS: Forty-three patients with 46 pathologically confirmed thyroid nodules underwent diffusion-weighted imaging (DWI) with 8 b values. Two observers measured the intravoxel incoherent motion (IVIM) parameters (D, f and D*) and the apparent diffusion coefficient (ADC), ADC600 and ADC990 values using whole-lesion (W-L) ROI and IVIM parameters using single-section (S-S) ROI delineation. The intraclass correlation coefficients (ICCs) and Bland-Altman plots were used to evaluate the intra- and interobserver variability. The diagnostic performance of these parameters was evaluated by generating receiver operating characteristic (ROC) curves. RESULTS: The ICC values of all IVIM with W-L ROI delineation were higher than those with S-S ROI delineation, and excellent intra- and interobserver reproducibility was obtained. According to the Bland-Altman plots, the 95% limits of agreement of the IVIM parameters determined by the W-L ROIs revealed smaller absolute intra- and interobserver variability than those determined by S-S ROIs. The D and ADC600 values obtained from the W-L ROIs were the most powerful parameters in differentiating benign from the malignant nodules [area under the ROC curve = 0.962 and 0.970, P = 0.771]. CONCLUSIONS: The W-L ROI of the thyroid was considered an effective method for obtaining IVIM measurements with excellent reproducibility for differentiating benign from malignant nodules.

8.
Ear Nose Throat J ; : 145561319901033, 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-31996037

RESUMO

OBJECTIVES: To propose a management algorithm for adult patients with sharp-pointed esophageal foreign-body impaction (EFBI) who have rigid endoscopy (RE) indications and to conduct a retrospective analysis of their data. METHODS: All adult patients who received RE at the Department of Otorhinolaryngology in Beijing Shijitan Hospital between January 2017 and May 2019 were enrolled. The demographics, clinical characteristics, and management data were collected and analyzed. RESULTS: A total of 130 patients were identified, 56.9% were female with median age 60 years. More than half (56.9%) of patients had foreign-body (FB) ingestion on holidays. The most frequent FBs were jujube pits (66.9%) and bones (23.8%). There is a significant female predominance in ingestion of jujube pits (65.5%, P = .005). The most common symptoms were odynophagia (49.2%) and sore throat (47.7%). The majority (96.8%) of FB founded were lodged at upper esophagus. In all, 74 patients were categorized as having mild complications and 54 having significant complications. Time interval from ingestion to presentation longer than 15 hours was an independent risk factor for significant complications, while esophagogram with barium as a protective factor. CONCLUSIONS: Long-time interval from ingestion to presentation will lead to high risk of significant complications. Computed tomography should be a prioritized imaging method for all patients suspected with EFBI, and multidisciplinary collaboration is recommended. Besides, mass education on eating habits is necessary.

9.
JCI Insight ; 5(3)2020 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-31935199

RESUMO

Alternative polyadenylation (APA) is a widespread and important mechanism in regulation of gene expression. Dysregulation of the 3' UTR cleavage and polyadenylation represents a common characteristic among many disease states, including lung fibrosis. In this study, we investigated the role of mammalian cleavage factor I-mediated (CFIm-mediated) APA in regulating extracellular matrix production in response to mechanical stimuli from stiffened matrix simulating the fibrotic lungs. We found that stiff matrix downregulated expression of CFIm68, CFIm59 and CFIm25 subunits and promoted APA in favor of the proximal poly(A) site usage in the 3' UTRs of type I collagen (COL1A1) and fibronectin (FN1) in primary human lung fibroblasts. Knockdown and overexpression of each individual CFIm subunit demonstrated that CFIm68 and CFIm25 are indispensable attributes of stiff matrix-induced APA and overproduction of COL1A1, whereas CFIm did not appear to mediate stiffness-regulated FN1 APA. Furthermore, expression of the CFIm subunits was associated with matrix stiffness in vivo in a bleomycin-induced mouse model of pulmonary fibrosis. These data suggest that stiff matrix instigates type I collagen biogenesis by selectively targeting mRNA transcripts for 3' UTR shortening. The current study uncovered a potential mechanism for regulation of the CFIm complex by mechanical cues under fibrotic conditions.

10.
Artigo em Inglês | MEDLINE | ID: mdl-31869282

RESUMO

The aim of this study was to investigate the impact of mycotoxin binders on the determination of aflatoxins in maize and maize gluten using various analytical methods, including ELISA, HPLC and LC-MS/MS. Three types of commercially available mycotoxin binders, yeast cell wall, mineral, and a mixture of mineral and bacterium, were investigated at inclusion levels of 0.1%, 0.2% and 0.4%. The binders were added to maize and maize gluten contaminated with aflatoxins at concentrations between 6.9 and 26.7 µg kg-1. The samples were analysed and the values were compared with corresponding controls (samples without binders) using ANOVA. The yeast cell wall binder had no significant effect (p=0.05) on the concentration of aflatoxins measured in either maize or maize gluten at any of the three inclusion levels, regardless of which analytical method was used. The mineral binder and the mixed mineral and bacterium binder had no significant effect (p=0.05) on the measured aflatoxin concentrations in either maize or maize gluten at any of the three inclusion levels when analysis was conducted using LC-MS/MS. Inclusion of these binders resulted in significant lower (p<0.01) detection of aflatoxins in both maize and maize gluten when analysis was conducted using ELISA; the effect was dose-dependent. They also resulted in significant lower detection of aflatoxins in maize extracted by methanol/water (70/30 v/v) (p<0.0001) and in maize gluten extracted by acetonitrile/water (80/20 v/v) (p<0.05) when analysis was conducted using HPLC. However, neither the mineral binder nor the mixed mineral and bacterium binder had significant effects (p=0.05) on aflatoxin concentrations measured in maize using HPLC, when extracted by acetonitrile/water (80/20 v/v). The study demonstrated that mycotoxin binders could result in underestimation of the levels of aflatoxin contamination, depending on the nature of the binder, the extraction solvent used in the analytical method, and the composition of tested sample.

11.
Foods ; 8(12)2019 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-31766674

RESUMO

The study explored punicalagin (PGN) as a wheat flour enhancer. The impact of PGN on the physicochemical and structural properties of wheat flour have been investigated. It turned out that PGN increased the formation time, stability, tensile resistance, extension, and viscoelasticity of the dough at the concentrations of 0.13 and 0.26 mg/g. Scan electron microscope images of the cross section of the dough displayed a more compact and ordered network structure with the addition of 0.13 and 0.26 mg/g PGN. Fourier transform infrared spectroscopy spectra indicated an increase of α-helix and ß-sheet content. However, nonlinear enhancing effects of PGN on the stretching properties, rheology, and structural properties of the dough were observed at concentrations of 0.39 and 0.52 mg/g. Correspondingly, cleavages were observed on the cross section of the dough and the content of ß-sheet showed a trend of reduction in the dough with addition of PGN at high concentrations. Taken together, these results indicated the potential usage of PGN as a wheat flour enhancer of natural origin at the concentration below 0.39 mg/g in the flour.

12.
Mikrochim Acta ; 186(12): 842, 2019 11 25.
Artigo em Inglês | MEDLINE | ID: mdl-31768653

RESUMO

Conjugated polymer hybrid nanoparticles (NPs) loaded with both indocyanine green (ICG) and 1,3-diphenylisobenzofuran (DPBF) are described. The NPs are dually functional in that ICG acts as the photosensitizer, and DPBF as a probe for singlet oxygen (1O2 probe). The nanoparticle core consists of the energy donating host poly(9,9-dioctylfluorenyl-2,7-diyl)-co-(2,5-p-xylene) (PFP). The polymer is doped with the energy acceptor DPBF. Ratiometric fluorometric detection of singlet oxygen is accomplished by measurement of fluorescence at wavelengths of 415 and 458 nm. In addition, the shell of the positively charged polymeric nanoparticles was modified, via electrostatic interaction, with negatively charged PDT drugs ICG. The integrated nanoparticles of type ICG-DPBF-PFP display effective photodynamic performance under 808-nm laser irradiation. The 1O2 sensing behaviors of samples are evaluated based on the ratiometric fluorescent responses produced by DPBF and PFP. 1O2 can be fluorimetically sensed with a detection limit of 28 µM. The multifunctional nanoprobes exhibit effortless cellular uptake, superior photodynamic activity and a rapid ratiometric response to 1O2. Graphical abstractSchematic of a dual-functional nanoplatform for photodynamic therapy (PDT) and singlet oxygen (1O2) feedback. It offers a new strategy for self-monitoring photodynamic ablation. FRET: fluorescence resonance energy transfer. Indocyanine green is attached in the shell of nanoparticles, and 1,3-diphenylisobenzofuran is doped into the energy donating host conjugated polymer.

13.
Int J Mol Sci ; 20(21)2019 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-31694199

RESUMO

Toxoplasma gondii is an intracellular parasite that infects humans and other warm-blooded animals. Exosomes are endocytic-derived vesicles released by cells, representing an important mode of intercellular communication. In exosomes, specific molecules of proteins, lipids, and mRNAs or miRNAs have been detected, some of which are capable of transferring biologically active molecules to recipient cells. Dendritic cells (DCs) are the only antigen-presenting cells (APCs) that activate the initial immune response. In this study, high-throughput sequencing was used to analyze the exosomal miRNA profile of DC2.4 cells infected with Toxoplasma gondii for 28 h, compared with those of uninfected DC2.4 cells. Differential exosomal miRNAs (DEmiRs) from these two cell groups were analyzed. Through high-throughput sequencing, 3434 DEmiRs were obtained, and 12 stably enriched DEmiRNAs were verified by Reverse Transcription-quantitative Polymerase Chain Reaction (RT-qPCR) and selected for further analysis. The target genes of these 12 miRNAs were predicted with online analysis software and subjected to bioinformatics analyses including protein-protein interaction (PPI) network analysis, key driver analysis (KDA), gene ontology (GO) enrichment, and Kyoto encyclopedia of genes and genomes (KEGG) pathway analysis. These DEmiRs were found to be associated with a variety of biological processes and signaling pathways involved in host ubiquitin system, innate immunity, biosynthesis, and transferase activity and could be potential biomarkers for T. gondii infection.

14.
Curr Med Sci ; 39(5): 843-851, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31612406

RESUMO

Throughout the duration of the New Cooperative Medical Scheme (NCMS), it was found that an increasing number of rural patients were seeking out-of-county medical treatment, which posed a great burden on the NCMS fund. Our study was conducted to examine the prevalence of out-of-county hospitalizations and its related factors, and to provide a scientific basis for follow-up health insurance policies. A total of 215 counties in central and western China from 2008 to 2016 were selected. The total out-of-county hospitalization rate in nine years was 16.95%, which increased from 12.37% in 2008 to 19.21% in 2016 with an average annual growth rate of 5.66%. Its related expenses and compensations were shown to increase each year, with those in the central region being higher than those in the western region. Stepwise logistic regression reveals that the increase in out-of-county hospitalization rate was associated with region (X1), rural population (X2), per capita per year net income (X3), per capita gross domestic product (GDP) (X4), per capita funding amount of NCMS (X5), compensation ratio of out-of-county hospitalization cost (X6), per time average in-county (X7) and out-of-county hospitalization cost (X8). According to Bayesian network (BN), the marginal probability of high out-of-county hospitalization rate was as high as 81.7%. Out-of-county hospitalizations were directly related to X8, X3, X4 and X6. The probability of high out-of-county hospitalization obtained based on hospitalization expenses factors, economy factors, regional characteristics and NCMS policy factors was 95.7%, 91.1%, 93.0% and 88.8%, respectively. And how these factors affect out-of-county hospitalization and their interrelationships were found out. Our findings suggest that more attention should be paid to the influence mechanism of these factors on out-of-county hospitalizations, and the increase of hospitalizations outside the county should be reasonably supervised and controlled and our results will be used to help guide the formulation of proper intervention policies.

15.
Diabetes Metab Res Rev ; : e3227, 2019 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-31655015

RESUMO

BACKGROUND: China has the largest dual diabetes and tuberculosis epidemic globally. No studies from mainland China have assessed the relationship between tuberculosis infection and diabetes. We conducted a population-based, observational study in eastern China to further explore this relationship. METHODS: A blood glucose, Quantiferon, and tuberculin skin test were administered at baseline. We compared tuberculosis infection in nondiabetics and diabetics. The cohort was additionally screened for tuberculosis progression over 5 years. RESULTS: Among 5405 participants, diabetics had elevated levels of Quantiferon and tuberculin positivity, largely driven by undiagnosed diabetics (compared with nondiabetics, adjusted odds ratios of 1.53; 95% confidence interval [CI], 1.05-2.23 and 1.58; 95% CI, 1.07-2.35 for tuberculin and Quantiferon positivity). During follow-up, the annual tuberculosis incidence was three times higher for diabetics compared with the entire cohort. CONCLUSIONS: These results suggest improving diabetic control through rapidly identifying undiagnosed diabetes may have indirect benefits to tuberculosis control. Targeting of preventive therapy to newly diagnosed diabetics at high-risk for progressive tuberculosis in China should be considered.

16.
Cardiol Res Pract ; 2019: 6857232, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31662902

RESUMO

Objectives: Chronic total occlusion (CTO) is prevalent in patients with prior coronary artery bypass grafting (CABG). However, data available concerning the prevalence of new-onset CTO of native vessels in patients with prior CABG is limited. Therefore, the objective of the study is to determine predictors for new native-vessel occlusion in patients with prior coronary bypass surgery. Methods: 354 patients with prior CABG receiving follow-up angiography are selected and analyzed in the present study, with clinical and angiographic variables being analyzed by logistic regression to determine the predictors of new native-vessel occlusion. Results: The overall new occlusion rate was 35.59%, with multiple CTOs (42.06%) being the most prevalent (LAD 24.60% and RCA 18.25%, respectively). Additionally, current smoking (OR: 2.67; 95% CI: 2.60 to 2.74; p=0.01), reduced ejection fraction (OR: 1.76; 95% CI: 1.04 to 2.97; p=0.04), severe stenosis (OR: 3.65; 95% CI: 2.55 to 5.24; p=0.01), and diabetes mellitus (OR: 1.86; 95% CI: 1.34 to 2.97; p=0.04) serve as the independent predictors for new native-vessel occlusion. Conclusion: As to high incidence of postoperative CTO, appropriate revascularization strategies and postoperative management should be taken into careful consideration.

17.
Sensors (Basel) ; 19(19)2019 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-31554300

RESUMO

As wireless communication technology keeps progressing, people's requirements for wireless communication quality are getting higher and higher. Wireless communication brings convenience, but also causes some problems. On the one hand, the traditional static and fixed spectrum allocation strategy leads to high wastefulness of spectrum resources. The direction of improving the utility of spectrum resources by combining the advantages of cooperative communication and cognitive radio has attracted the attention of many scholars. On the other hand, security of communication is becoming an important issue because of the broadcasting nature and openness of wireless communication. Physical-layer security has been brought into focus due to the possibility of improving the security in wireless communication. In this paper, we propose an anti-wiretap spectrum-sharing scheme for cooperative cognitive radio communication systems which can secure the information transmission for the two transmission phases of the cooperative communication. We maximized the secondary system transmission rate by jointly optimizing power and bandwidth while ensuring the primary system achieves its secrecy transmission rate. Useful insights of the proposed anti-wiretap spectrum-sharing scheme are given in the simulation results. Moreover, several system parameters are shown to have a big impact for the simulation results.

18.
Med Sci Monit ; 25: 7138-7148, 2019 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-31543510

RESUMO

BACKGROUND The relationship between clopidogrel-resistance (CR) and polymorphism located in genes encoding clopidogrel metabolism-related enzymes has not been fully explored. Thus far, few studies on CR-associated polymorphism have been conducted in the Chinese population. The purpose of this study was to identify CYP2C19 polymorphism associated with CR in patients with acute coronary syndrome in China. MATERIAL AND METHODS There were 125 patients with acute coronary syndromes (ACS) selected for this study. Of these, 27 patients (21.6%) showed CR (less than 10% reduction in platelet accumulation rate), while the remaining 98 patients (78.4%) were non-clopidogrel-resistant (NCR). RESULTS There were significant differences in the allele frequencies of CYP2C19 (rs4244285) (P=0.03) and CYP2C19 (rs4986893) (P=0.005) between the 2 groups; however, there was no significant difference in allele frequencies of ABCB1 (rs1045642) (P=0.661) and PON1 (rs662) (P=0.690) between the 2 groups. The null allele in the CYP2C19 (rs4244285) [odds ratio (OR)=5.317, 95% confidence interval (CI) 1.542-26.428, P=0.001] and CYP2C19 (rs4986893) (OR=4.295, 95%CI 1.312-17.517, P=0.013) is one of the causes of CR in patients with ACS in China. CONCLUSIONS The CYP2C19 polymorphism (rs4244285 and rs4986893) is the correlative factor of CR in patients with ACS in China. It was found that the null allele in the CYP2C19 polymorphism was related to the higher CR risk. According to the key role of CYP2C19 in the clopidogrel activation and the evaluated role of CYP2C19 in this study, further studies should be carried out to formulate therapeutic alternative methods for CR in patients with ACS.

19.
J Ind Microbiol Biotechnol ; 46(12): 1757-1768, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31512096

RESUMO

Through our previous study, we found an up-regulation in the expression of nitrite reductase (nirS) in the isothiazolone-resistant strain of Pseudomonas aeruginosa. However, the definitive molecular role of nirS in ascribing the resistance remained elusive. In the present study, the nirS gene was deleted from the chromosome of P. aeruginosa ATCC 9027 and the resulting phenotypic changes of ΔnirS were studied alongside the wild-type (WT) strain under aerobic conditions. The results demonstrated a decline in the formations of biofilms but not planktonic growth by ΔnirS as compared to WT, especially in the presence of benzisothiazolinone (BIT). Meanwhile, the deletion of nirS impaired swimming motility of P. aeruginosa under the stress of BIT. To assess the influence of nirS on the transcriptome of P. aeruginosa, RNA-seq experiments comparing the ΔnirS with WT were also performed. A total of 694 genes were found to be differentially expressed in ΔnirS, of which 192 were up-regulated, while 502 were down-regulated. In addition, these differently expressed genes were noted to significantly enrich the carbon metabolism along with glyoxylate and dicarboxylate metabolisms. Meanwhile, results from RT-PCR suggested the contribution of mexEF-oprN to the development of BIT resistance by ΔnirS. Further, c-di-GMP was less in ΔnirS than in WT, as revealed by HPLC. Taken together, our results confirm that nirS of P. aeruginosa ATCC 9027 plays a role in BIT resistance along with biofilm formation and further affects several metabolic patterns under aerobic conditions.


Assuntos
Nitrito Redutases/metabolismo , Pseudomonas aeruginosa/enzimologia , Aerobiose , Biofilmes , Regulação Bacteriana da Expressão Gênica , Nitrito Redutases/genética , Pseudomonas aeruginosa/genética , Transcriptoma
20.
Nanotechnology ; 31(6): 065101, 2019 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-31550685

RESUMO

In this study, fluorescence-encoded magnetic biocompatible nanoparticles (NPs) were constructed from CdSe@ZnS quantum dots (QDs) and Fe3O4 nanoparticles with a one-step reprecipitation-encapsulation method. The resultant hybrid NPs exhibit small size (∼130 nm in diameter), highly bright QDs, two-color emissions (green and red) under single-wavelength excitation, easy separation with a magnet and efficient cellular internalization. Energy transfer between the incorporated QDs was studied to better tailor the encoded fluorescence, and 11 barcodes were obtained by adjusting the ratio of green and red QDs. We used four sets of the barcodes to tag specific cancer cells (HepG2) as a proof-of-concept, and distinguished each set according to respective overlayed fluorescence images using laser confocal microscopy. Moreover, the incorporated Fe3O4 NPs endowed as-constructed optical barcode superparamagnetic property by T 2-enhanced magnetic resonance effect with an r 2 value of 145.25 s-1 mM-1 at 3 T. These results suggest that the multifunctional NPs are very promising for discriminating different cells and dual-modality imaging.

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