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Abstract Objective To validate the performance of Mycob. T Stainer and Scanner (MTSS) for detecting acid-fast bacilli (AFB). Methods A total of 3,816 sputum samples from 1,515 tuberculosis (TB) suspects were tested at the Anhui Provincial Chest Hospital and the Linyi People's Hospital from April-August, 2016. Each specimen was placed on two smear slides. One slide was stained by the ziehl-neelsen (ZN) method to be read by conventional microscopy (CM). The other slide was stained and scanned by MTSS. All specimens were decontaminated with 4% NaOH, and then inoculated into solid culture. The performance of MTSS was assessed. Results MTSS produced higher average positivity rate (27.96%) as compared with the CM (26.83%). The overall sensitivity and specificity of MTSS were 78.9% and 93.9%, respectively. The sensitivity and specificity of CM was 77.4% and 95.0%, respectively. Conclusion MTSS exhibited a favorable performance in the detection of AFB. It may be an alternative to CM for screening TB. [ABSTRACT FROM AUTHOR]

Abstract: Well-crystallized one-dimensional (1D) SnO2 nanobelts were in situ prepared using a simple water-assisted chemical vapor deposition (CVD) method. The small Sn particles with Au-modifications were used as source materials instead of big size Sn grains to ensure the high yield of SnO2 belts. The Au layer was modified on the small Sn particles by treating Sn powders in HAuCl4 solution combined with the UV irradiation. The as-prepared SnO2 nanobelts were characterized by SEM, HRTEM, XRD, EDS and XPS. These results indicate that the growth temperature plays an important role in controlling the length-to-width ratio of nanobelts. The length-to-width ratio decreases with the growth temperature from 850°C to 1000°C. The nanobelts prepared at 850°C shows a single-crystalline tetragonal rutile phase with a high length-to-width ratio (approximately tens of microns in length and 40–70nm in width). However, below 850°C, nanobelts cannot be formed. The as-prepared nanobelts exhibited excellent sensing properties compared with SnO2 nanoparticles and high sensing selectivity towards NO2. The high sensing selectivity to NO2 is attributed to the oxygen vacancies presenting in the as-prepared nanobelts. [Copyright &y& Elsevier]

Abstract: Interstitial lung diseases are primarily attributable to occupational or environmental exposures to dusts and irritants. We report on a case of interstitial lung disease, possibly secondary to iron exposure. Our male patient presented with cough and shortness of breath of more than 20 years’ duration after his occupational exposure had ended. A chest radiograph showed patchy shadows throughout both lower fields, and computed tomography showed ground-glass-like opacification, with fibrosis in the lower lobes. A lung biopsy revealed foamy cells in the alveolar spaces, with bronchiolitis obliterans. Microelemental analysis showed an increased level of iron in the lung tissue. After treatment with N-acetyl cysteine effervescent tablets, the patient’s symptoms gradually improved. This probable case of iron-induced interstitial lung disease suggests the importance of obtaining a patient’s history of occupational and environmental exposures for the sake of an accurate diagnosis. [Copyright &y& Elsevier]

Abstract: A large number of isolates from the Fusarium graminearum clade representing all regions in China with a known history of Fusarium head blight (FHB) epidemics in wheat were assayed using PCR to ascertain their trichothecene mycotoxin chemotypes and associated phylogenetic species and geographical distribution. Of the 299 isolates assayed, 231 are from F. asiaticum species lineage 6, which produce deoxynivalenol and 3-acetyldeoxynivalenol (3-AcDON); deoxynivalenol and 15-acetyldeoxynivalenol (15-AcDON); and nivalenol and 4-acetylnivalenol (NIV) mycotoxins, with 3-AcDON being the predominant chemotype. Ninety-five percent of this species originated from the warmer regions where the annual average temperatures were above 15°C, based on the climate data of 30y during 1970–1999. However, 68 isolates within F. graminearum species lineage 7 consisted only of 15-AcDON producers, 59% of which were from the cooler regions where the annual average temperatures were 15°C or lower. Identification of a new subpopulation of 15-AcDON producers revealed a molecular distinction between F. graminearum and F. asiaticum that produce 15-AcDON. An 11-bp repeat is present in F. graminearum within their Tri7 gene sequences but is absent in F. asiaticum, which could be directly used for differentiating the two phylogenetic species of the F. graminearum clade. [Copyright &y& Elsevier]

Abstract: Nanocrystalline porous CdSe thin films with particle diameter of 6.0 and 8.0 nm were prepared by chemical deposition on SnO2 conducting glass substrates. The broadening of the excitonic transitions in the absorption spectrum due to the size distribution and an increase of bandgap energy compared with the bulk CdSe are observed. Electrolyte electroabsorption (EEA) spectrum measured in polysulfide solution exhibits the characteristic second derivative lineshape of the quantum-confined CdSe nanoparticles. A quadratic modulation voltage dependence of EEA signals indicates that the electrical field distribution of nanocrystalline porous CdSe thin films is different significantly from that of bulk CdSe thin films. [Copyright &y& Elsevier]

Abstract: Transcription factors play a central role in cell biology through binding to target DNA elements and regulating gene expression. In this study, we used the p53 tumour suppressor as a model transcription factor to develop an imaging based assay to measure DNA binding. The assay utilizes fluorescence imaging microscopy to detect labelled p53 bound to DNA coated on microbeads. We demonstrate the ability to multiplex the assay by interrogating simultaneous binding to variant DNA sequences present on tractable beads. Additionally, the assay measures activation of p53 for increased DNA binding by a known peptide in addition to reactivation of mutant p53 by a small molecule. It may therefore be adaptable to a high-content imaging screen for compounds capable of restoring the function of mutant p53 associated with cancer. [Copyright &y& Elsevier]

Non-small cell lung cancers (NSCLC) have unique mutation patterns, and some of these mutations may be used to predict prognosis or guide patient treatment. Mutation profiling before and during treatment often requires repeated tumor biopsies, which is not always possible. Recently, cell-free, circulating tumor DNA (ctDNA) isolated from blood plasma has been shown to contain genetic mutations representative of those found in the primary tumor tissue DNA (tDNA), and these samples can readily be obtained using non-invasive techniques. However, there are still no standardized methods to identify mutations in ctDNA. In the current study, we used a targeted sequencing approach with a semi-conductor based next-generation sequencing (NGS) platform to identify gene mutations in matched tDNA and ctDNA samples from 42 advanced-stage NSCLC patients from China. We identified driver mutations in matched tDNA and ctDNA in EGFR, KRAS, PIK3CA, and TP53, with an overall concordance of 76%. In conclusion, targeted sequencing of plasma ctDNA may be a feasible option for clinical monitoring of NSCLC in the near future. [ABSTRACT FROM AUTHOR]

Abstract: Porous crystalline SnO2 thin films were electrodeposited from an oxygen-saturated acid aqueous solution of SnCl2 containing different amounts of butyl rhodamine B (BRhB) at 70°C. BRhB can not only be dissolved in the acid deposition solution due to its amidocyanogen substitute, where HCl was added to suppress hydrolysis of SnCl2, but also be adsorbed on the surface of SnO2 through its carbonate substitute. Therefore, it was used as a structure-directing agent to control the growth of SnO2 crystals and then the crystalline structure and surface morphology of the deposited film. The electrodeposited thin films show porous morphology and rutile-type SnO2 crystalline structure due to the effects of BRhB on the growth, and these structural features can be adjusted by changing the added amount of BRhB. The SnO2 thin film electrodeposited with addition of BRhB exhibits electrocatalytic characteristic enhancement on oxidation of phenol due to its porous structure. [Copyright &y& Elsevier]

In this paper, the physical model of low voltage Direct-current (DC) glow discharge in cross field is established. Based on the magneto-hydrodynamic method (MHD), the mathematical expression of steady-state plasma physical parameters under cross field condition is derived, and the influence of magnetic field on low-pressure glow plasma physical parameters is analyzed. The theoretical results show that the magnetic field can effectively increase the electron density and ion density of plasma at low pressure. The magnetic field can increase the glow discharge current, and the introduction of the magnetic field makes the plasma concentrate to the discharge center. The effects of parallel field and cross field on glow discharge are compared by experiments. The experimental results show that the cross field has more influence on the glow plasma density than the parallel field, and the experimental results are consistent with the theoretical results. The main research highlights of this paper are as follows: • The analytical form of plasma parameters of flat plate DC glow discharge in transverse magnetic field is derived. • The influence of cross field on plasma parameters is more obvious than that of parallel field. • The cross field is easier to produce glow at lower pressure. [ABSTRACT FROM AUTHOR]

• The highly active DON-degrading bacterial strain Devosia sp. D6-9 was isolated. • Strain D6-9 catabolized DON via epimerization to form 3-keto-DON and 3- epi -DON. • A dehydrogenase and two reductases are responsible for DON detoxification in D6-9. • Three recombinant enzymes efficiently degraded DON present in wheat grains. • Residues S497, E499, and E535 in QDDH are essential for DON-oxidizing activity. The Fusarium mycotoxin deoxynivalenol (DON) is typically controlled by fungicides. Here, we report DON detoxification using enzymes from the highly active Devosia strain D6-9 which degraded DON at 2.5 μg/min/108 cells. Strain D6-9 catabolized DON to 3-keto-DON and 3- epi -DON, completely removing DON in wheat. Genome analysis of three Devosia strains (D6-9, D17, and D13584), with strain D6-9 transcriptomes, identified three genes responsible for DON epimerization. One gene encodes a quinone-dependent DON dehydrogenase QDDH which oxidized DON into 3-keto-DON. Two genes encode the NADPH-dependent aldo/keto reductases AKR13B2 and AKR6D1 that convert 3-keto-DON into 3- epi -DON. Recombinant proteins expressed in E sch e richia coli efficiently degraded DON in wheat grains. Molecular docking and site-directed mutagenesis revealed that residues S497, E499, and E535 function in QDDH's DON-oxidizing activity. These results advance potential microbial and enzymatic elimination of DON in agricultural samples and lend insight into the underlying mechanisms and molecular evolution of DON detoxification. [ABSTRACT FROM AUTHOR]

In this study, an effective BiOBr/Bi 2 O 2 CO 3 p - n heterojunction was established via a precipitation conversion method at ambient temperature. The light response of the hybrid was broadened for 16 nm compared with that of Bi 2 O 2 CO 3. More importantly, the charge transfer in BiOBr/Bi 2 O 2 CO 3 heterojunction was greatly promoted as evidenced by photocurrent, ESI and PL results. So the photocatalytic ability of BiOBr/Bi 2 O 2 CO 3 was greatly improved towards degradation of organic pollutants. The sample of Br amount of 0.094 wt% showed the optimal photoactivity for RhB degradation, with a rate constant k of 14.8 times as much as that of Bi 2 O 2 CO 3. The reason is ascribed to the established built-in electrical field and resulted band matching between BiOBr and Bi 2 O 2 CO 3. Based on the results, the migration mechanism of photoinduced charges at the interface of the heterojunction was put forward. This work provides a useful perspective in design and fabrication of Bi(III)-based heterostructure with an enhanced photocatalytic activity. Effective BiOBr/Bi 2 O 2 CO 3 p - n heterojunction was facilely constructed by precipitation conversion at room temperature. The hybrid exhibited obviously boosted photocatalytic activity for pollutant degradation due to the formation of built-in electrical field and resulted band matching between BiOBr and Bi 2 O 2 CO 3. Image 1 • BiOBr/Bi 2 O 2 CO 3 p - n heterojuntion was facilely constructed by precipitation conversion. • The decoration of trace BiOBr on Bi 2 O 2 CO 3 surface greatly improves the charge mobility. • The heterojuntion exhibits an enhanced photoactivity of 14.8 folds than bare Bi 2 O 2 CO 3. • The reconstruction and migration of carriers in the heterojuntion interface was proposed. [ABSTRACT FROM AUTHOR]

The contamination of food with Aspergillus flavus and subsequent aflatoxins is considered as one of the most severe safety problems in the world. The application of microorganisms and the produced bio-active compounds is considered as the most promising method for controlling foodborne pathogens and mycotoxins contamination both in pre- and post-harvest. Vt-7, identified as Enterobacter asburiae , was able to completely inhibit the growth of Aspergillus flavus (AF) and other seven important fungal pathogens by the production of volatiles. Additionally, it can also significantly inhibited AF infection on peanuts in storage, down-regulated the gene expression of aflatoxin biosynthesis and eventually prevented aflatoxins production. Scanning electron microscope further proved that Vt-7 volatiles prevented conidia germination of AF on peanut surface, and severely destroyed the conidia structure. Gas chromatography – tandem mass spectrometry revealed that two abundant compounds (1-Pentanol and Phenylethyl Alcohol) were involved in the volatile profiles. They showed great antagonistic activity against AF with minimal inhibitory concentration at 200 μL/L. Therefore, E. asburiae Vt-7, and volatiles 1-Pentanol and Phenylethyl Alcohol were effective agents in controlling AF and aflatoxins in peanut during storage. They will provide novel strategies for the application of microbe and bio-active compounds against fungal pathogens and mycotoxins in food and grains during storage. • E.asburiae Vt-7 greatly inhibited the growth of AF and other seven fungal pathogens. • Vt-7 volatile prevented AF infection and AFT production in peanuts during storage. • Antifungal volatiles from Vt-7 were proved as phenylethyl alcohol and 1-pentanol. • MIC for phenylethyl alcohol and 1-pentanol against AF was 200 μL/L. [ABSTRACT FROM AUTHOR]