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1.
Bioresour Technol ; 311: 123533, 2020 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-32460131

RESUMO

Denitrification in mixed culture system has been extensively researched to date, but few studies have focused on accelerating the process using redox mediators to promote electron transfer. Strain L2, an iron-reducing bacteria, can remove 75.44% of nitrate under temperature of 30.60 °C, pH of 6.75 and Fe2+ concentration of 27.86 mg·L-1. Additionally, the removal rate of nitrate reached 1.516 mg·L-1·h-1 in 8 h with the addition of 0.030 mmol·L-1 2-hydroxy-1,4-naphthoquinone (HNQ), which increased by 1.38 times than control group. Furthermore, analysis by fluorescence spectroscopy, flow cytometer and gas chromatography demonstrated that HNQ positively stimulated denitrification. This study provides a reference for enhancing denitrification in mixed culture and lays the foundation for the practical application of redox mediators in groundwater treatment.

2.
Medicine (Baltimore) ; 99(20): e19894, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32443291

RESUMO

RATIONALE: Pyopneumopericardium related to bungee jumping is a rare occurrence in the current antibiotic era. We present a case of esophagus-seeded Streptococcus sanguinis pyopneumopericardium in a young man with tuberculosis who had just completed bungee jumping. PATIENT CONCERN: A 27-year-old man was hospitalized with a 1-day history of fever, chest tightness, and intermittent sharp chest pain after bungee jumping for the first time. DIAGNOSES: Clinical examinations, thoracentesis, and pericardiocentesis revealed pyopneumopericardium, pyopneumomediastinum, and suppurative pleurisy secondary to bungee-jumping-related traumas. Pericardial fluid cultures were positive for S sanguinis, and Mycobacterium tuberculosis complex genetic test was positive in both sputum and pleural effusion. INTERVENTIONS: The patient improved with drainage and comprehensive antimicrobial therapy. OUTCOMES: The patient developed constrictive pericarditis and underwent pericardiectomy after 6 months of anti-tuberculosis treatment. During the 6-month follow-up after surgery, he recovered uneventfully. LESSONS: This case adds to the long list of bungee-jumping complications. Early diagnosis to initiate appropriate therapy is critical for pyopneumopericardium patients to achieve good outcomes.

3.
Fitoterapia ; 144: 104603, 2020 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-32360288

RESUMO

The phytochemical study of the aerial part of Mesona chinensis led to the isolation of five new caffeic acid oligomers (1-5), as well as four known analogues (6-9). The structures of the new compounds including their absolute configurations were elucidated by comprehensive spectroscopic analysis, chemical method, and quantum-chemical electronic circular dichroism (ECD) calculation. Among the isolates, compound 7 showed significant in vitro antiviral activity on respiratory syncytial virus (RSV).

4.
J Zhejiang Univ Sci B ; 21(5): 408-410, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32425008

RESUMO

As of Apr. 22, 2020, the World Health Organization (2020) has reported over 2.4 million confirmed coronavirus disease 2019 (COVID-19) patients and 169 151 deaths. Recent articles have uncovered genomic characteristics and clinical features of COVID-19 (Chan et al., 2020; Chang et al., 2020; Guan et al., 2020; Zhu et al., 2020), while our understanding of COVID-19 is still limited. As suggested by guidelines promoted by the General Office of National Health Commission of the People's Republic of China (2020) (from Versions 1 to 6), discharged standards for COVID-19 were still dependent on viral real-time polymerase chain reaction (RT-PCR) tests of respiratory specimens, showing that recovered COVID-19 patients with twice negative RT-PCR could meet discharge criteria. Here, we examined two cases in which nucleic acid test results were inconsistent with clinical and radiological findings, leading to suboptimal care.


Assuntos
Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/transmissão , Pneumonia Viral/diagnóstico , Pneumonia Viral/transmissão , Adulto , Betacoronavirus , China , Técnicas de Laboratório Clínico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pandemias , Alta do Paciente , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Escarro/virologia
5.
Ann Hum Genet ; 2020 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-32396266

RESUMO

The objectives of the present study were to identify CYP4V2 genetic variants and characterize their functional consequences. A total of 26CYP4V2 genetic variants were identified, including seven novel variants in 60 randomly selected healthy subjects. Six protein-coding variants were studied, including three novel variants (L22V, R287T, and G410C) and three previously reported variants (R36S, Q259K, and H331P). The cDNA sequences encoding each amino acid variant and the wild-type CYP4V2 protein were cloned into the pcDNA/PDEST40 expression vector and transfected into eukaryotic 293T cells for overexpression of the CYP4V2 coding variants. CYP4V2 H331P and CYP4V2 G410C exhibited significant decreases in activity for lauric acid oxidation (20-30% of wild-type activity), when compared to the wildtype, which was correlated with low expression of CYP4V2 H331P and G410C substituted proteins. The other four CYP4V2 amino variants were comparable to wild-type CYP4V2 for lauric acid metabolism. The CYP4V2 H331P and G410C substitutions were predicted to cause a structural change through in silico analysis. In conclusion, the present study provides functional information about CYP4V2 genetic variants. These findings will be valuable for interpreting individual variations in phenotypes associated with CYP4V2 function in the clinical setting.

6.
J Cardiothorac Surg ; 15(1): 97, 2020 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-32410655

RESUMO

BACKGROUND: There has been an increasing number of children with congenital heart disease that undergo primary or second systemic-pulmonary shunt, while there are few reports on the second systemic-pulmonary shunt. Therefore, this study summarizes the experience of second systemic-pulmonary shunt for congenital heart disease in our hospital. METHODS AND RESULTS: Sixty-five children with congenital heart disease who underwent systemic-pulmonary shunt for the second time in our hospital were analyzed. At the early stage after the operation, cyanosis improved and SpO2 significantly increased. One patient died in hospital (1.54%) and the causes of death were aggravated atrioventricular regurgitation, low cardiac output syndrome, and liver failure. Early complications occurred in 18 patients (27.7%). All the children were rechecked in our hospital every 3-6 months and the McGoon index significantly increased. CONCLUSION: Systemic-pulmonary artery shunt can promote pulmonary vascular development, improve cyanosis symptoms, and increase the chance of radical treatment in children with pulmonary vascular dysplasia.

7.
Artigo em Inglês | MEDLINE | ID: mdl-32418134

RESUMO

Single denitrification using bacteria has been widely investigated, but few studies have focused on the simultaneous removal of nitrate, phosphorus. and tetracycline. Strain L2, an iron-reducing bacteria, was immobilized using chitosan/polyvinyl alcohol to simultaneously remove nitrate and phosphorus. The effects of carbon/nitrogen ratio (1:1, 1.5:1, and 2:1), initial Fe2+ concentration (0, 15, and 30 mg·L-1), and HRT (2, 4, and 6 h) were assessed in bioreactors and optimum conditions were established. Results showed that the nitrate and phosphorus removal efficiency reached 100.00% (2.697 mg·L-1·h-1) and 81.93% (1.533 mg·L-1·h-1) under the conditions of carbon/nitrogen of 2:1, Fe2+ concentration of 30 mg·L-1 and HRT of 6 h. The precipitation of bioreactor, which identified as FeOOH by XRD, had significant adsorption on tetracycline. The results of high-throughput sequencing indicated that strain L2 played a significant role in denitrification. This bioreactor provided effective method for the treatment of polluted water contaminated by nitrate, phosphorus, and tetracycline.

9.
J Med Econ ; : 1-6, 2020 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-32362156

RESUMO

Aims: Cold agglutinin disease (CAD) is a rare subtype of autoimmune hemolytic anemia associated with increased thromboembolism risk and early mortality. Healthcare resource utilization (HRU) in CAD has not been reported. We aimed to compare HRU of patients with CAD with a matched non-CAD cohort in the United States.Materials and methods: Patients with CAD were identified from 2006 to 2016 in the Optum-Humedica database using CAD terms in clinical notes and hematologist review. Patients were required to have Integrated Delivery Network records and ≥6 months' follow-up before and after the first CAD mention date (index date). Patients with CAD were matched to a non-CAD cohort based on demographics. Multivariate analyses assessed inpatient hospitalizations, outpatient visits, emergency room visits, and transfusion use between cohorts 6 months before and 12 months after the index date.Results: Of 814 patients with CAD, 410 met inclusion criteria and were matched to 3,390 patients without CAD. Mean age of patients with CAD was 68.0 years; approximately 62% were female. In the 12 months after the index date, mean inpatient hospitalizations (0.83 vs. 0.25), outpatient visits (17.26 vs. 6.77), emergency room visits (0.55 vs. 0.32), and transfusion days (1.05 vs. 0.05) were higher for patients with CAD than the matched non-CAD cohort (all p < .0001). Similarly, in the 6 months before the index date, patients with CAD had higher HRU than matched patients without CAD for all measures evaluated.Limitations: Results of this study are based on patient information from the Optum-Humedica database, which is limited to commercially insured patients and may not represent the overall CAD population.Conclusions: CAD places a substantial burden on patients and healthcare systems. In addition, the high HRU for patients with CAD observed in the 6 months before diagnosis indicates that disease awareness and better diagnostic practices may be needed.

10.
J Comput Chem ; 2020 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-32352189

RESUMO

A periodic hybrid density functional theory computational strategy is presented to model the heterointerface between the methylammonium lead iodide (MAPI) perovskite and titanium dioxide (TiO2 ), as found in perovskite solar cells (PSC), where the 4-chlorobenzoic acid (CBA) ligand is used to improve the stability and the band alignment at the interface. The CBA ligand acts as a bifunctional linker to efficiently connect the perovskite and the oxide moieties, ensuring the stability of the interface through Ti-O and Pb-Cl interactions. The computed density of states reveals that the perovskite contributes to the top of the valence band while the oxide contributes to the bottom of the conduction band with a direct bandgap of 2.16 eV, indicating a possible electron transfer from MAPI to TiO2 . Dipole moment analysis additionally reveals that the CBA ligand can induce a favorable effect to improve band alignment and thus electron transfer from MAPI to TiO2 . This latter has been quantified by calculation of the spin density of the reduced MAPI/CBA/TiO2 system and indicates an almost quantitative (99.94%) electron transfer from MAPI to TiO2 for the surface engineered system, together with an ultrafast electron injection time in the femtosecond timescale. Overall, the proposed DFT-based computational protocol therefore indicates that surface engineering and the use of a bifunctional linker can lead to a better stability, together with improved band alignment and electron injection in PSC systems.

11.
J Mol Cell Cardiol ; 142: 53-64, 2020 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-32251671

RESUMO

Diabetes mellitus is a serious metabolic condition associated with a multitude of cardiovascular complications. Moreover, the prevalence of diabetes in heart failure populations is higher than that in control populations. However, the role of cardiomyocyte alterations in type 2 diabetes mellitus (T2DM) has not been well characterized and the underlying mechanisms remain elusive. In this study, two patients who were diagnosed as T2DM were recruited and patient-specific induced pluripotent stem cells (iPSCs) were generated from urine epithelial cells using nonintegrated Sendai virus. The iPSC lines derived from five healthy subjects were used as controls. All iPSCs were differentiated into cardiomyocytes (iPSC-CMs) using the monolayer-based differentiation protocol. T2DM iPSC-CMs exhibited various disease phenotypes, including cellular hypertrophy and lipid accumulation. Moreover, T2DM iPSC-CMs exhibited higher susceptibility to high-glucose/high-lipid challenge than control iPSC-CMs, manifesting an increase in apoptosis. RNA-Sequencing analysis revealed a differential transcriptome profile and abnormal activation of TGFß signaling pathway in T2DM iPSC-CMs. We went on to show that inhibition of TGFß significantly rescued the hypertrophic phenotype in T2DM iPSC-CMs. In conclusion, we demonstrate that the iPSC-CM model is able to recapitulate cellular phenotype of T2DM. Our results indicate that iPSC-CMs can therefore serve as a suitable model for investigating molecular mechanisms underlying diabetic cardiomyopathies and for screening therapeutic drugs.

12.
Chemistry ; 2020 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-32315480

RESUMO

A phloroglucinol-terpene adduct (PTA) collection consisting of twenty-four molecules featuring three skeletons was discovered from Baeckea frutescens. Inspired by its biosynthetic hypothesis, we synthesized this PTA collection by reductive activation of stable phloroglucinol precursors into highly reactive ortho -quinone methide (o-QM) intermediates and subsequently Diels-Alder cycloaddition. We also demonstrated for the first time the generation process of the active o-QM by performing dynamic nuclear magnetic resonance (NMR) and HPLC-MS monitoring experiments. Moreover, the PTA collection showed significant antifeedant effect toward the Plutella xylostella larvae.

13.
Artigo em Inglês | MEDLINE | ID: mdl-32275129

RESUMO

Spinel Li4Ti5O12 is considered as a promising anode material for long-life lithium ion batteries due to the negligible volumetric variation during the insertion and extraction of the Li ion. Phase transition is an inevitable process during the migration of the Li ion and the transition process and mechanism need detailed investigation down to atomic scale. In this study, we investigated the behavior and mechanism on the phase transition of Li4Ti5O12 through in situ transmission electron microscopy. It has been found that the spinel structured Li4Ti5O12 was gradually transformed to rocksalt structured under electron beam irradiation. A sharp interface with an epitaxial relationship was observed between the transformed rocksalt phase and the parent spinel phase. Furthermore, the heterostructure with different crystal structures of Li4Ti5O12 has been precisely tailored with electron beam irradiation. Our detailed in situ TEM results and theoretical calculations lead to unprecedented level on understanding of phase transition mechanism in Li4Ti5O12. This study demonstrates a possible approach to precisely engineer the crystal structure of materials and to realize well-designed heterostructure in electrode materials.

14.
Gut ; 69(6): 1002-1009, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32213556

RESUMO

OBJECTIVE: The SARS-CoV-2-infected disease (COVID-19) outbreak is a major threat to human beings. Previous studies mainly focused on Wuhan and typical symptoms. We analysed 74 confirmed COVID-19 cases with GI symptoms in the Zhejiang province to determine epidemiological, clinical and virological characteristics. DESIGN: COVID-19 hospital patients were admitted in the Zhejiang province from 17 January 2020 to 8 February 2020. Epidemiological, demographic, clinical, laboratory, management and outcome data of patients with GI symptoms were analysed using multivariate analysis for risk of severe/critical type. Bioinformatics were used to analyse features of SARS-CoV-2 from Zhejiang province. RESULTS: Among enrolled 651 patients, 74 (11.4%) presented with at least one GI symptom (nausea, vomiting or diarrhoea), average age of 46.14 years, 4-day incubation period and 10.8% had pre-existing liver disease. Of patients with COVID-19 with GI symptoms, 17 (22.97%) and 23 (31.08%) had severe/critical types and family clustering, respectively, significantly higher than those without GI symptoms, 47 (8.14%) and 118 (20.45%). Of patients with COVID-19 with GI symptoms, 29 (39.19%), 23 (31.08%), 8 (10.81%) and 16 (21.62%) had significantly higher rates of fever >38.5°C, fatigue, shortness of breath and headache, respectively. Low-dose glucocorticoids and antibiotics were administered to 14.86% and 41.89% of patients, respectively. Sputum production and increased lactate dehydrogenase/glucose levels were risk factors for severe/critical type. Bioinformatics showed sequence mutation of SARS-CoV-2 with m6A methylation and changed binding capacity with ACE2. CONCLUSION: We report COVID-19 cases with GI symptoms with novel features outside Wuhan. Attention to patients with COVID-19 with non-classic symptoms should increase to protect health providers.


Assuntos
Betacoronavirus , Técnicas de Laboratório Clínico , Infecções por Coronavirus , Trato Gastrointestinal , Pandemias , Pneumonia Viral , Adulto , China , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/fisiopatologia , Infecções por Coronavirus/virologia , Feminino , Trato Gastrointestinal/fisiopatologia , Trato Gastrointestinal/virologia , Humanos , Masculino , Pessoa de Meia-Idade , Pneumonia Viral/diagnóstico , Pneumonia Viral/epidemiologia , Pneumonia Viral/fisiopatologia , Pneumonia Viral/virologia , Fatores de Risco
15.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 45(1): 61-67, 2020 Jan 28.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-32132299

RESUMO

Protein tyrosine phosphatase H-type receptor (PTPRH) gene encodes a gastric cancer associated protein, which exerts its biological function through tyrosine phosphorylation in the post-translational COOH- terminal region. PTPRH is abnormally expressed in a variety of tumors, and its biological function is closely related to the occurrence, development and prognosis of tumors.


Assuntos
Neoplasias Gástricas , Humanos , Fosforilação , Proteínas Tirosina Fosfatases , Proteínas , Tirosina
16.
Artigo em Inglês | MEDLINE | ID: mdl-32193699

RESUMO

BACKGROUND: Malignant peripheral nerve sheath tumors (MPNSTs) are rare aggressive sarcomas with poor prognosis. More than half of MPNSTs develop from benign precursor tumors associated with neurofibromatosis type 1 (NF1) which is a tumor suppressor gene disorder. Early detection of malignant transformation in NF1 patients is pivotal to improving survival. The primary aim of this study was to evaluate the role of immuno-modulators as candidate biomarkers of malignant transformation in NF1 patients with plexiform neurofibromas as well as predictors of response to immunotherapeutic approaches. METHODS: Sera from a total of 125 NF1 patients with quantified internal tumor load were included, and 25 of them had MPNSTs. A total of six immuno-modulatory factors (IGFBP-1, PD-L1, IFN-α, GM-CSF, PGE-2, and AXL) were measured in these sera using respective ELISA. RESULTS: NF1 patients with MPNSTs had significantly elevated PD-L1 levels in their sera compared to NF1 patients without MPNSTs. By contrast, AXL concentrations were significantly lower in sera of NF1-MPNST patients. IGFBP-1 and PGE2 serum levels did not differ between the two patient groups. IFN-α and GM-CSF were below the detectable level in most samples. CONCLUSION: The immuno-modulator PD-L1 is upregulated in MPNST patients and therefore may provide as a potential biomarker of malignant transformation in patients with NF1 and as a response predictor for immunotherapeutic approaches.

17.
Bioresour Technol ; 307: 123196, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32220820

RESUMO

A novel biomaterial FeCl3/CaCl2/KH2PO4 modified municipal sludge biochar (FCPC) was synthesized. And the impacts of critical factors such as HRT, temperature and C/N ratio on simultaneous denitrification, dephosphorization and Cd(II) removal were investigated. Results show that the highest nitrate removal efficiency reached 92.22% (8.49 mg·L-1·h-1) in test group A and approximately 100% (9.19 mg·L-1·h-1) in test group B. Very low phosphate concentrations (approximately 2.50 mg/L) were detected in the effluent. The average removal efficiency of Cd(II) reached 86.40% (4.42 mg·L-1·h-1) in experimental group A and 90.15% (4.61 mg·L-1·h-1) in experimental group B. Gas emissions and biological precipitation in the bioreactors were monitored, further to confirming contaminant removal mechanisms. Additionally, Cupriavidus H29 was found to contribute dominantly to the FCPC bioreactor activity.


Assuntos
Cádmio , Cupriavidus , Materiais Biocompatíveis , Reatores Biológicos , Desnitrificação , Nitratos , Nitrogênio , Fósforo , Proteobactérias
18.
Bioresour Technol ; 305: 123081, 2020 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-32135349

RESUMO

This study presents the novel composite material TMCC/PAA/SA@Fe(TPSA), a bacteria immobilized carrier for use in bioreactor systems to enhance the simultaneous removal efficiency of nitrate, Ni(II) and phosphorus. The influence of various operational factors were evaluated on the performance of nitrate, phosphorus and Ni(II) removal. Results demonstrate that under optimum conditions of an hydraulic retention time (HRT) of 8 h and pH 7.0, nitrate and phosphorus removal reached nearly 100% and 61.7%, respectively. When the initial Ni(II) concentration was 1 mg/L, approximately 100% Ni(II) removal efficiency was achieved. Furthermore, the morphology and components of the TPSA immobilized bacterial pellets were analyzed to investigate the mechanism of simultaneous nitrate, Ni(II) and phosphorus removal. Microbial metabolism was more active in the experimental reactor compared with control, although high concentrations of Ni(II) could inhibit bacterial activity.

19.
Sensors (Basel) ; 20(6)2020 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-32183399

RESUMO

In this paper, to solve the problem of detecting network anomalies, a method of forming a set of informative features formalizing the normal and anomalous behavior of the system on the basis of evaluating the Hurst (H) parameter of the network traffic has been proposed. Criteria to detect and prevent various types of network anomalies using the Three Sigma Rule and Hurst parameter have been defined. A rescaled range (RS) method to evaluate the Hurst parameter has been chosen. The practical value of the proposed method is conditioned by a set of the following factors: low time spent on calculations, short time required for monitoring, the possibility of self-training, as well as the possibility of observing a wide range of traffic types. For new DPI (Deep Packet Inspection) system implementation, algorithms for analyzing and captured traffic with protocol detection and determining statistical load parameters have been developed. In addition, algorithms that are responsible for flow regulation to ensure the QoS (Quality of Services) based on the conducted static analysis of flows and the proposed method of detection of anomalies using the parameter Hurst have been developed. We compared the proposed software DPI system with the existing SolarWinds Deep Packet Inspection for the possibility of network traffic anomaly detection and prevention. The created software components of the proposed DPI system increase the efficiency of using standard intrusion detection and prevention systems by identifying and taking into account new non-standard factors and dependencies. The use of the developed system in the IoT communication infrastructure will increase the level of information security and significantly reduce the risks of its loss.

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