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2.
Chemosphere ; 255: 126942, 2020 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-32387732

RESUMO

Knowledge of the geochemical behavior of uranium is critical for the safe disposal of radioactive wastes. Biotite, a Fe(II)-rich phyllosilicate, is a common rock-forming mineral and a major component of granite or granodiorite. This work comprehensively studied the sorption of U(VI) on biotite surface with batch experiments and analyzed the uranium speciation with various spectroscopic techniques, including X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM) and time-resolved fluorescence spectra (TRFS). Our results indicated that uranyl ions could penetrate into the interlayer of biotite, this ion-exchange process was pH-dependent and only favorable under acidic condition. Instead of precipitation or reduction to uraninite, the TRFS results strongly suggests U(VI) forms surface complexes under the neutral and alkaline condition, though the number and structure of surface species could not be identified accurately. Besides, the oxidation of biotite with peroxide hydrogen showed that structural Fe(II) would have a very low redox reactivity. With leaching experiments, zeta potential analysis and thermodynamics calculation, we discussed the possible reasons for inhibition of U(VI) reduction at the biotite-water interface. Our results may provide insight on interaction mechanism of uranium at mineral-water interface and help us understand the migration behavior of uranium in natural environments.

5.
Arch Virol ; 165(6): 1453-1461, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32279138

RESUMO

Human immunodeficiency virus type 1 (HIV-1) infection remains a severe public health problem worldwide. In this study, we investigated the distribution of HIV-1 subtypes and the prevalence of drug resistance mutations (DRMs) among patients with HIV-1 infection in Henan Province, China. HIV-1 strains in blood samples taken from inpatients and outpatients visiting the Sixth People's Hospital of Zhengzhou from August 2017 to July 2019 with a viral load (VL) greater than 1000 copies/ml were subjected to subtype and DRMs analysis. Out of a total of 769 samples, subtype and DRM data were obtained from 657 (85.43%) samples. Phylogenetic analysis based on partial pol gene sequences indicated that the most commonly found genotype was subtype B (45.51%, 299/657), followed by CRF01_AE (28.61%, 188/657), CRF07_BC (15.68%, 103/657), CRF08_BC (0.76%, 5/657), C (0.61%, 4/657), A (0.30%, 2/657), and others (8.52%, 56/657). Circulating recombinant forms (CRFs) were most commonly found in patients who were naïve to antiretroviral treatment (ART) (68.67%, 160/233). The percentage of patients with one or more major drug-resistance mutations was 50.99% (335/657), and it was 6.44% (15/233) in ART-naive patients that were primarily infected with subtype B (17.74%). Resistance mutations were most common at codons 65, 103, 106, 184, and 190 of the reverse transcriptase gene and codon 46 of the protease gene. Our study provides detailed information about the distribution of HIV-1 subtypes and the incidence of drug resistance mutations of different subtypes in ART-experienced and naïve patients. This can guide policymakers in making decisions about treatment strategies against HIV-1.


Assuntos
Farmacorresistência Viral/genética , Infecções por HIV/epidemiologia , Infecções por HIV/virologia , HIV-1/efeitos dos fármacos , HIV-1/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antirretrovirais/uso terapêutico , Criança , Pré-Escolar , China/epidemiologia , Feminino , Infecções por HIV/tratamento farmacológico , HIV-1/isolamento & purificação , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Filogenia , Filogeografia , Carga Viral , Adulto Jovem
6.
Trials ; 21(1): 296, 2020 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-32228673

RESUMO

After publication of our article [1] the authors have notified us of two typos in the Trial status.

7.
Cytotechnology ; 2020 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-32086694

RESUMO

This study described a successful application of the Quality by Design (QbD) approach to pseudorabies virus (PRV) production process development in a fixed-bed bioreactor using the serum-free medium (SFM). The innovated tube-fixed-bed bioreactor was used as a scale-down model of the fixed-bed bioreactor for process development. Risk analysis was performed using Ishikawa diagram combined with failure mode effects analysis (FMEA). The comparative experiment was performed to screen proper medium for adherent African green monkey kidney (Vero) cells from three commercially available SFMs (VP-SFM, ProVERO-1 and Vero-A). The Vero-A medium showed as an outstanding one for further study. The PRV titer in harvest medium was consider as Critical Quality Attribute (CQA) and the Critical Process Parameters (CPPs) [time of infection (TOI), multiplicity of infection (MOI) and initial inoculation cell density] ranked high with risk priority number (RPN) were taken into design of experiment (DoE) methodology. Then prediction model of PRV production process was established and a robust PRV production process was explored. Under the robust setpoint conditions, the Xcell 1 L laboratory-scale fixed-bed bioreactor yielded PRV titer up to 7.87 log10 TCID50/mL at 3 dpi, which was comparable with that in the tube-fixed-bed bioreactor. Combination of the tube-fixed-bed bioreactor and QbD approach could further accelerate the development of a robust virus production process.

9.
Yeast ; 37(4): 305-312, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32050051

RESUMO

A highly efficient and targeted clustered regularly interspaced short palindromic repeats (CRISPR)/Cas9 gene editing system was constructed for Pichia pastoris (syn Komagataella phaffii). Plasmids containing single guide RNA and the methanol expression regulator 1 (MXR1) homology arms were used to precisely edit the transcriptional activator Mxr1 on the P. pastoris genome. At the S215 amino acid position of Mxr1, one, two, and three nucleotides were precisely deleted or inserted, and S215 was also mutated to S215A via a single-base substitution. Sequencing of polymerase chain reaction (PCR) amplicons in the region spanning MXR1 showed that CRISPR/Cas9 technology enabled efficient and precise gene editing of P. pastoris. The expression levels of several of the Mxr1-targeted genes, AOX1, AOX2, DAS1, and DAS2, in strains containing the various mutated variants of MXR1, were then detected through reverse transcription PCR following induction in methanol-containing culture medium. The frameshift mutations of Mxr1 led to almost zero transcription of AOX1, DAS1, and DAS2, while that of AOX2 was reduced to 60%. For the Mxr1 S215A mutant, the transcription of AOX1, AOX2, DAS1, and DAS2 was also reduced by nearly 60%. Based on these results, it is apparent that the transcription of AOX1, DAS1, and DAS2 is exclusively regulated by Mxr1 and serine phosphorylation at Mxr1 residue 215 is not critical for this function. In contrast, the transcription of AOX2 is mainly dependent on the phosphorylation of this residue. CRISPR/Cas9 technology was, therefore, successfully applied to the targeted editing of MXR1 on the P. pastoris genome, and it provided an effective method for the study of this transcription factor and its targets.

10.
Nanotechnology ; 31(25): 254002, 2020 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-32050192

RESUMO

A TiO2 with exposed (001) facets/Bi4O5Br2 nanosheets heterojunction (TNS/BOB) was fabricated via a hydrothermal and electrostatic self-assembly method. The photocatalytic activity for NO removal was evaluated under simulated solar light irradiation. Through optimizing the content of TNS nanosheets, the photo-oxidative NO removal rate of 15% TNS/BOB was increased by up to 54.3%. This value is much higher than that of the individual components TNS (31.1%) and BOB (37.7%). Through capturing experiments and electron spin resonance (ESR) measurements, the main active species in the photocatalytic process were identified as ·[Formula: see text] and ·OH. Discrete Fourier transform computation results and ESR tests revealed that the photo-induced electrons in TNS should recombine with the holes in BOB, leading to effectively promoted charge separation at the TNS/BOB interface through the Z-type charge transfer. This work showed that with appropriate facet control and heterojunction design TiO2 can be used as an effective visible-light photocatalyst material.

11.
Artigo em Chinês | MEDLINE | ID: mdl-32086926

RESUMO

Objective:The aim of this study is to determine the accuracy of RSI and RFS in the diagnosis of hypopharyngeal reflux (LPR), the scores of RSI and RFS were compared in different age groups. To explore the RSI and RFS scoring thresholds for diagnosis of LPR in different age groups. Method:From January 2017 to March 2019, 258 patients with suspected LPR in our hospital outpatient clinic completed the RSI and RFS scales. According to their age, 258 patients with RSI>13 and RFS>7 were selected. They were divided into group A (18-<40 years, n=86), group B (40-<60 years, n=107) and group C (≥60 years, n=65). The diagnosis was confirmed by 24 h pH-metry. The diagnostic rate, RSI and RFS scores were compared among the three groups. ROC curve was used to analyze the optimal thresholds for the diagnosis of LPR by RSI and RFS scores. Result:Among the three groups, group C had the highest diagnostic rate(93.85%). There was no significant difference in RFS score among the three groups (P>0.05), RSI score was significantly different (P<0.05), RSI score of group A and group B was higher than that of group C (P<0.05). According to ROC analysis, the best RSI cutoffs for diagnosing LPR in group C was 11, and the area under the ROC curve was 0.866. Conclusion:The RSI score is a good criterion for the diagnosis of LPR. The diagnostic threshold of RSI in elderly patients is different from that in young patients. For elderly patients, the diagnostic threshold for the recommended RSI score is 11.


Assuntos
Fatores Etários , Refluxo Laringofaríngeo/diagnóstico , Adolescente , Adulto , Idoso , Humanos , Laringe/fisiopatologia , Pessoa de Meia-Idade , Faringe/fisiopatologia , Adulto Jovem
12.
Plant Physiol Biochem ; 149: 121-131, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32062332

RESUMO

Flower senescence is classified into ethylene-dependent and ethylene-independent manners and determines the flower longevity which is valuable for ornamental plants. However, the manner of petal senescence in tulip is still less defined. In this study, we characterized the physiological indexes in the process of petal senescence, as well as metabolic and ethylene responses in tulip cultivar 'American Dream', and further identified the role of ethylene biosynthesis genes TgACS by transgenic and transient assays. Primary metabolites profiling revealed that sugars, amino acids and organic acids preferentially accumulated in senescent petals. Additionally, senescence-associated genes were identified and significantly up-regulated, coupled with increased ROS contents, rapid water loss and accelerated cell membrane breakdown. Moreover, ethylene production was stimulated as evidenced by increasing in ACS activity and ethylene biosynthesis-related genes expression. Exogenous treatment of cutting flowers with 1-MCP or ethephon resulted in delayed or enhanced petal senescence, respectively. Transient down-regulation of TgACS by VIGS assay in tulip petals delayed senescence, while over-expressed TgACS1 in tobacco promoted leaf senescence. Taken together, this study provides evidences to certify ethylene roles and TgACS functions during flower senescence in tulip.

13.
J Vasc Access ; : 1129729820904833, 2020 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-32072851

RESUMO

PURPOSE: To evaluate the influence of body posture change on the peripherally inserted central catheter tip position in Chinese cancer patients. METHODS: A prospective observational trial was conducted in a tertiary cancer hospital from August to September 2018. After the insertion of peripherally inserted central catheter, chest X-ray films were taken to check the catheter tip in the upright and supine positions, respectively. The distance from the carina to the catheter tip was separately measured on both chest films by nurses. The primary study outcome was the distance and direction of the catheter tip movement. The secondary study outcome was to analyze the influence factors on the catheter tip movement. The third study outcome was to observe the related adverse events caused by the catheter tip movement. RESULTS: A total of 79 patients were included, the results showed that 61 moved cephalad, 14 moved caudally, and 4 did not move with body change from the supine to the upright position. When moved cephalad, the mean distance was 19.34 ± 11.95 mm; when moved caudally, the mean distance was -15.83 ± 8.97 mm. The difference between the two positions was statistically significant (p < 0.001). There was also a statistically significant difference between catheter tip movement direction and body mass index (p = 0.009) and height (p = 0.015). Two patients developed arrhythmias; no cardiac tamponade was found due to body posture change. CONCLUSION: The results of this work implied that the tips of the catheter tend to shift toward the cephalad with body change from the supine to the upright position. A study involving a larger sample size is needed to find more information in the future.

14.
Int Immunopharmacol ; 81: 106261, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32058928

RESUMO

Exacerbation of chronic obstructive pulmonary disease (COPD) is characterized by acute airway inflammation and mucus hypersecretion, which is by far the most costly aspect of its management. Thus, it is essential to develop therapeutics with low side effects for CODP exacerbation. Sodium tanshinone IIA sulfonate (STS) is a water-soluble derivative of tanshinone IIA isolated as the major active component of Chinese herbal medicine Danshen. Although it possesses anti-inflammatory, anti-oxidative and anti-apoptotic properties, it remains unknown whether STS protects against COPD exacerbation. In this study, we challenged cigarette smoke (CS)-exposed mice with lipopolysaccharide (LPS), and then treated these mice with STS. We found that STS significantly ameliorated pulmonary inflammatory responses, mucus hypersecretion and lung function decline in CS-exposed mice challenged with LPS. STS treatment also significantly attenuated increased IL-6 and IL-8 releases from cigarette smoke extract (CSE)-treated human bronchial epithelial cells (16HBE) challenged with LPS. Mechanistically, STS reduced activation of ERK1/2 and NF-κB in lungs of CS-exposed mice and CSE-treated 16HBE cells challenged with LPS. Taken together, STS protects against acute exacerbation of CS-induced lung injury, which provides a promising and potential therapeutic avenue to halt acute exacerbation of COPD.

15.
J Affect Disord ; 265: 85-90, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31957696

RESUMO

BACKGROUND: Fatigue influences doctors' physical and mental health seriously, additionally, the topic has received wide attention recently. This study aimed to identify the association among resilience, perceived organizational support (POS) and fatigue, and to further explore whether POS could be a moderator in the association between resilience and fatigue in Chinese doctors. METHODS: A cross-sectional study was conducted in Liaoning Province in China in 2018. Out of 1000 randomly selected doctors, 866 completed the Chalder Fatigue Scale, the Connor-Davidson Resilience Scale, Survey of Perceived Organizational Support, and the questions about demographic characteristics and job condition variables. The association among resilience, POS and resilience × POS interaction with physical and mental fatigue were examined by hierarchical multiple regression. Simple slope analysis was conducted to visualize the interaction. RESULTS: The association between resilience and physical fatigue was gradually increased in the low (1 standard deviation [SD] below the mean, ß = -0.127, P< 0.05), mean (ß = -0.292, P < 0.05) and high (1 SD above the mean, ß = -0.457, P < 0.05) groups of POS. Additionally, the association was also different in the low (1 SD below the mean, ß = -0.240, P < 0.01), mean (ß = -0.357, P < 0.01) and high (1 SD above the mean, ß = -0.474, P < 0.01) groups of POS. LIMITATIONS: Due to the cross-sectional design, the study cannot draw any conclusion of causal relationships among study variables. CONCLUSIONS: POS could moderate the association among resilience, physical and mental fatigue. More interventions related to resilience and POS will be helpful to alleviate fatigue among Chinese doctors.

16.
Int J Syst Evol Microbiol ; 70(3): 1895-1902, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31961285

RESUMO

A Gram-stain-negative, facultatively aerobic, rod-shaped, motile by gliding and pink-pigmented bacterial strain, designated ELS1360T, was isolated from a lake sediment sample collected in Inner Mongolia, PR China. Strain ELS1360T grew optimally at 33 °C, at pH 6.5-7.0 and without NaCl. Strain ELS1360T exhibited 97.3, 97.1 and 96.9 % 16S rRNA gene sequence similarities to Hymenobacter aquatilis HMF3095T, Hymenobacter luteus JCM 30328T and Hymenobacter latericoloratus JCM 30327T, respectively, and 90.4-96.9 % to other members of the genus Hymenobacter. Results of phylogenetic analysis based on 16S rRNA gene sequences showed that strain ELS1360T belonged to the genus Hymenobacter and clustered with H. luteus JCM 30328T and H. latericoloratus JCM 30327T. The predominant cellular fatty acids were iso-C15:0, summed feature 3 and C16:1ω5c. Strain ELS1360T contained MK-7 as the sole menaquinone. The major polar lipids contained phosphatidylethanolamine and two unidentified lipids. The genomic DNA G+C content of strain ELS1360T was 57.1 mol%. Based on the results of our phylogenetic, phenotypic, genotypic and chemotaxonomic analyses, it is concluded that strain ELS1360T represents a novel species within the genus Hymenobacter, for which the name Hymenobacter sediminis sp. nov. is proposed. The type strain is ELS1360T (=KCTC 62449T=MCCC 1H00319T).


Assuntos
Cytophagaceae/classificação , Sedimentos Geológicos/microbiologia , Lagos/microbiologia , Filogenia , Técnicas de Tipagem Bacteriana , Composição de Bases , China , Cytophagaceae/isolamento & purificação , DNA Bacteriano/genética , Ácidos Graxos/química , Fosfatidiletanolaminas/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/química
17.
Brain Imaging Behav ; 2020 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-31900891

RESUMO

Altered functional connectivity (FC) of the thalamus has been proven to be an important finding in tinnitus patients. Tinnitus can be effectively desensitized by sound therapy. However, it is still unclear whether and how sound therapy affects the FC of the thalamus. Resting-state functional magnetic resonance imaging data and anatomical data were longitudinally collected from 25 idiopathic tinnitus patients before and after 12 weeks of sound therapy by using adjusted narrow band noise and from 25 matched healthy controls at the same time interval without any intervention. The FC of bilateral thalami were analyzed by setting the left and right thalamus as the regions of interest. Significant main effect of group on the FC of the thalamus were found mainly in the key components of the default mode network, limbic network, salience network, cognitive control network, auditory network and occipital region. FC values between the thalamus, inferior frontal gyrus (IFG), and anterior cingulate cortex (ACC) featured higher values in the tinnitus group at baseline compared to the healthy controls and restoration in tinnitus patients after treatment. Decreased Tinnitus Handicap Inventory (THI) scores and decreased FC values between the right thalamus and right IFG were positively correlated (r = 0.476, P = 0.016). Abnormal FC of the thalamus is associated with multiple brain networks. Sound therapy has a normalizing effect on the enhanced FC of the thalamus-IFG and thalamus-ACC, representing decreased tinnitus attention control and less involvement of the noise-canceling system.

18.
Br J Pharmacol ; 177(12): 2743-2764, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31976548

RESUMO

BACKGROUND AND PURPOSE: Tetramethylpyrazine (TMP) was originally isolated from the traditional Chinese herb ligusticum and the fermented Japanese food natto and has since been synthesized. TMP has a long history of beneficial effects in the treatment of many cardiovascular diseases. Here we have evaluated the therapeutic effects of TMP on pulmonary hypertension (PH) in animal models and in patients with pulmonary arterial hypertension (PAH) or chronic thromboembolic pulmonary hypertension (CTEPH). EXPERIMENTAL APPROACH: Three well-defined models of PH -chronic hypoxia (10% O2 )-induced PH (HPH), monocrotaline-induced PH (MCT-PH) and Sugen 5416/hypoxia-induced PH (SuHx-PH) - were used in Sprague-Dawley rats, and assessed by echocardiography, along with haemodynamic and histological techniques. Primary cultures of rat distal pulmonary arterial smooth muscle cells (PASMCs) were used to study intracellular calcium levels. Western blots and RT-qPCR assays were also used. In the clinical cohort, patients with PAH or CTEPH were recruited. The effects of TMP were evaluated in all systems. KEY RESULTS: TMP (100 mg·kg-1 ·day-1 ) prevented rats from developing experimental PH and ameliorated three models of established PH: HPH, MCT-PH and SuHx-PH. The therapeutic effects of TMP were accompanied by inhibition of intracellular calcium homeostasis in PASMCs. In a small cohort of patients with PAH or CTEPH, oral administration of TMP (100 mg, t.i.d. for 16 weeks) increased the 6-min walk distance and improved the 1-min heart rate recovery. CONCLUSION AND IMPLICATIONS: Our results suggest that TMP is a novel and inexpensive medication for treatment of PH. Clinical trial is registered with www.chictr.org.cn (ChiCTR-IPR-14005379).

19.
J Pharm Sci ; 109(2): 959-965, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31604085

RESUMO

In this study, a novel tube-fixed-bed bioreactor which consists of a TubeSpin bioreactor 50 tube and 0.44 g macrocarriers was developed as the scale-down model of a fixed-bed bioreactor. The adherent Vero cell-based pseudorabies virus (PRV) production process was tested in this novel model. The Vero cells grew well in the tube-fixed-bed bioreactor, and the cell density reached 5.8 × 106 cells/mL after 7 days of culture. The PRV production parameters (time of infection, multiplicity of infection, and harvest process) were optimized in the tube-fixed-bed bioreactor. Then the optimized process (time of infection = 3 days, multiplicity of infection = 0.001 and multiple harvest process) was scaled up 25-fold to an Xcell 1-L laboratory-scale fixed-bed bioreactor and 125-fold to an Xcell 5-L fixed-bed bioreactor successfully. The total PRV harvest in the Xcell 1-L bioreactor at 5 days after infection (dpi) was 10.25 log10 TCID50 which corresponds to 177,827 doses of vaccine. The total PRV harvest in the Xcell 5-L bioreactor at 5 dpi was 11.13 log10 TCID50 which corresponded to 1,348,962 doses of vaccine. The comparable growth curve, metabolism, and PRV production profile of the scaled-up bioreactors confirmed the feasibility and scalability of the tube-fixed-bed bioreactor as a scale-down model of the fixed-bed bioreactor for virus production process development.

20.
J Hazard Mater ; 382: 121121, 2020 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-31491668

RESUMO

To fully utilize the solar light, photocatalyst with broad spectrum response from UV to near-infrared (NIR) is desirable. In this work, ternary mixed valent Bi2O4-Bi4O7-BiO2-x with rich oxygen vacancy has been synthesized through one-pot hydrothermal treatment of NaBiO3. The results showed that through adjusting the hydrothermal conditions, oxygen vacancy-rich Bi2O4-Bi4O7-BiO2-x nanocomposites with much higher efficiency than single or mixed bismuth oxides (Bi2O4, Bi4O7, BiO2-x and Bi4O7-BiO2-x,) can be synthesized for photocatalytic degradation of bisphenol A (BPA) under UV, visible, and NIR light irradiation. In addition, the liquid chromatography-mass spectrometer (LC-MS) characterization demonstrated that BPA was oxidized to 4-isopropenyphenol first and the rings were opened sequentially under NIR light irradiation. Further detection of reactive species indicated that holes, O2-, and OH were the main oxidizing species in the degradation system. The experimental observations and density functional theory (DFT) calculations suggested that both type-II and the Z-scheme charge transfer with oxygen vacancies as electrons and holes mediators were formed at the interfaces of Bi2O4, Bi4O7, and BiO2-x, resulting in a very efficient separation of photogenerated charge carriers in the composite. This work adds to the growing potential of mixed valent bismuth oxides based photocatalysts and is expected to accelerate the pace of the development of new-generation photocatalysts with high efficiency utilizing full-spectrum solar light.

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