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1.
Sci Total Environ ; 760: 144040, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33341633

RESUMO

Environmental pollution caused by antibiotic resistance genes (ARGs) has attracted wide concerns, and various approaches have been proposed to control ARGs dissemination. TiO2 photoexcitation under UV irradiation has been used for such a purpose. But the actual UV intensity is insufficient to trigger the production of reactive oxygen species (ROS) in the aqueous environment. Thus, it is interesting to know how mild photoexcitation of TiO2 with low-intensity UV affects the horizontal transfer of ARGs. In this work, the impact of TiO2 photoexcitation on the transductant efficiency of constructed filamentous phage gM13 to its host Escherichia coli TG1 was investigated. Although individual treatment with nano-TiO2 and UV irradiation both improved the phage infection, TiO2 photoexcitation exhibited a clear synergistic promotion effect. However, excessive UV irradiation resulted in a decrease in transductant formation, implying severe oxidative damage to the phage and bacterial cells. Extracellular ROS produced by moderate photoexcitation of TiO2 could increase the outer membrane permeability, which facilitated phage infection. The increase in pili synthesis induced by intracellular ROS provided more sites for phage recognition and invasion in the presence of TiO2 photoexcitation, which contributed to the transduction process. Our work provides a novel insight into the impact of TiO2 photoexcitation on ARGs diffusion and is helpful for better understanding non-toxic environmental effect of nanomaterials.


Assuntos
Bacteriófagos , Antibacterianos/farmacologia , Bacteriófagos/genética , Resistência Microbiana a Medicamentos , Genes Bacterianos , Titânio/farmacologia
3.
Echocardiography ; 2020 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-33368575

RESUMO

BACKGROUND: Double-chambered left ventricle (DCLV) is extremely rare. Challenges remain in accurate diagnosis of DCLV by echocardiography, because it is easily confused with left ventricular diverticulum, left ventricular aneurysm, ventricular septal defect, etc. Herein, we reviewed echocardiographic characteristics of DCLV and evaluated the accuracy of echocardiographic diagnosis. METHODS: Clinical and echocardiographical databases of two heart centers were reviewed. Nine children with DCLV of superior-inferior arrangement were studied retrospectively. RESULTS: Normal elliptical geometry of LV cavity is preserved in DCLV. Fibromuscluar bundles separate LV into the main chamber and the accessory chamber. The associated malformations included ventricular septal defects, mitral regurgitation, mitral valve stenosis, pulmonary stenosis, and left ventricular noncompaction in our study. Eight of nine subjects with DCLV of superior-inferior arrangement were diagnosed correctly by initial echocardiographic examination, and one case was mistaken as left ventricular diverticulum. CONCLUSIONS: Double-chambered left ventricle could be diagnosed and followed up by echocardiography. The morphological classification is a simplified way to improve diagnostic accuracy.

4.
Environ Pollut ; : 115943, 2020 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-33158624

RESUMO

Electrochemically active bacteria (EAB) are effective for the bioreduction of nitroaromatic compounds (NACs), but the exact reduction mechanisms are unclear yet. Therefore, 3-nitrobenzenesulfonate (NBS) was used to explore the biodegradation mechanism of NACs by EAB. Results show that NBS could be anaerobically degraded by Shewanella oneidensis MR-1. The generation of aminoaromatic compounds was accompanied with the NBS reduction, indicating that NBS was biodegraded via reductive approach by S. oneidensis MR-1. The impacts of NBS concentration and cell density on the NBS reduction were evaluated. The removal of NBS depends mainly on the transmembrane electron transfer of S. oneidensis MR-1. Impairment of Mtr respiratory pathway was found to mitigate the reduction of NBS, suggesting that the anaerobic biodegradation of NBS occurred extracellularly. Knocking out cymA severely impaired the extracellular reduction ability of S. oneidensis MR-1. However, the phenotype of ΔcymA mutant could be compensated by the exogenous electron mediators, implying the trans-outer membrane diffusion of mediators into the periplasmic space. This work provides a new insight into the anaerobic reduction of aromatic contaminants by EAB.

5.
J Autoimmun ; : 102562, 2020 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-33168359

RESUMO

Adult-onset Still's disease (AOSD) is a rare autoinflammatory disease with systemic involvement, and its pathophysiology remains unclear. Genome-wide association studies (GWAS) in the Chinese population have revealed an association between AOSD and the major histocompatibility complex (MHC) locus; however, causal variants in the MHC remain undetermined. In the present study, we identified independent amino-acid polymorphisms in human leukocyte antigen (HLA) molecules that are associated with Han Chinese patients with AOSD by fine-mapping the MHC locus. Through conditional analyses, we identified position 34 in HLA-DQα1 (p = 1.44 × 10-14) and Asn in HLA-DRß1 position 37 (p = 5.12 × 10-11) as the major determinants for AOSD. Moreover, we identified the associations for three main HLA class II alleles: HLA-DQB1*06:02 (OR = 2.70, p = 3.02 × 10-14), HLA-DRB1*15:01 (OR = 2.44, p = 3.66 × 10-13), and HLA-DQA1*01:02 (OR = 1.97, p = 1.09 × 10-9). This study reveals the relationship between functional variations in the class II HLA region and AOSD, implicating the MHC locus in the pathogenesis of AOSD.

6.
Chem Commun (Camb) ; 2020 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-33220665

RESUMO

We here describe an alkynylative [5+1] benzannulation of 3-acetoxy-1,4-enynes with terminal alkynes, which enables both the construction of a benzene ring skeleton and intermolecular incorporation of an alkynyl group in a single reaction using Pd and Cu cooperative catalysts. The method represents efficient access to internal aryl alkynes through divergent functionalization of two terminal alkyne components: one alkyne serves as the one-carbon unit to realize the [5+1] benzannulation and the other alkyne as a nucleophile terminates the reaction.

7.
Org Lett ; 22(21): 8544-8549, 2020 11 06.
Artigo em Inglês | MEDLINE | ID: mdl-33075230

RESUMO

Using terminal alkyne as a nontraditional one-carbon (C1) unit and silylborane as an external silicon pronucleophile, a relay palladium/copper-catalyzed silylative [5 + 1] benzannulation of 3-acetoxy-1,4-enynes for producing polysubstituted arylsilanes, especially including bioactive motif-based analogues, in a single reaction step through benzene ring skeleton assembly and silyl intermolecular incorporation cascades is developed. Mechanistic studies show that this reaction allows the terminal sp-hybridized carbon atom in terminal alkynes as a C1 unit via cleavage of two π-bonds and one C(sp)-H bond.

8.
Chin Med J (Engl) ; 133(21): 2521-2531, 2020 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-32925287

RESUMO

BACKGROUND: Secukinumab demonstrated sustained efficacy in patients with ankylosing spondylitis (AS) through 5 years in pivotal Phase III studies. Here, we present efficacy and safety results (52-week) of secukinumab in patients with AS from the MEASURE 5 study. METHODS: MEASURE 5 was a 52-week, Phase III, China-centric study. Eligible patients were randomly assigned (2:1) to receive subcutaneous secukinumab 150 mg or placebo weekly for the first five doses and then once every 4 weeks (q4w). All placebo patients switched to secukinumab 150 mg q4w starting at Week 16. Primary endpoint was Assessments of SpondyloArthritis international Society (ASAS) 20 at Week 16. Randomization was stratified by region (China vs. non-China). RESULTS: Of 458 patients (secukinumab 150 mg, N = 305; placebo, N = 153) randomized, 327 (71.4%) were from China and 131 (28.6%) were not from China. Of these, 97.7% and 97.4% patients completed Week 16 and 91.1% and 95.3% (placebo-secukinumab) patients completed Week 52 of treatment. The primary endpoint was met; secukinumab significantly improved ASAS20 response at Week 16 vs. placebo (58.4% vs. 36.6%; P < 0.0001); corresponding rate in the Chinese population was 56.0% vs. 38.5% (P < 0.01). All secondary efficacy endpoints significantly improved with secukinumab 150 mg in the overall population at Week 16; responses were maintained with a trend toward increased efficacy from Week 16 to 52. No new or unexpected safety signals were reported up to Week 52. CONCLUSIONS: Secukinumab 150 mg demonstrated rapid and significant improvement in signs and symptoms of AS. Secukinumab was well tolerated and the safety profile was consistent with previous reports. Efficacy and safety results were comparable between the overall and Chinese populations. TRIAL REGISTRATION: ClinicalTrials.gov, NCT02896127; https://clinicaltrials.gov/ct2/show/NCT02896127?term=NCT02896127&draw=2&rank=1.

9.
Virol Sin ; 2020 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-32236817

RESUMO

Porcine adenoviruses (PAdVs) are classified into three species, PAdV-A, PAdV-B, and PAdV-C. The genomes of PAdV-A and PAdV-C have been well characterized. However, the genome of PAdV-B has never been completely sequenced, and the epidemiology of PAdV-B remains unclear. In our study, we have identified a novel strain of PAdV-B, named PAdV-B-HNU1, in porcine samples collected in China by viral metagenomic assay and general PCR. The genome of PAdV-B-HNU1 is 31,743 bp in length and highly similar to that of California sea lion adenovirus 1 (C. sea lion AdV-1), which contains typical mastadenoviral structures and some unique regions at the carboxy-terminal end. Especially, PAdV-B-HNU1 harbors a dUTPase coding region not clustering with other mastadenoviruses except for C. sea lion AdV-1 and a fiber coding region homologous with galectin 4 and 9 of animals. However, the variance of GC contents between PAdV-B-HNU1 (55%) and C. sea lion AdV-1 (36%) indicates their differential evolutionary paths. Further epidemiologic study revealed a high positive rate (51.7%) of PAdV-B-HNU1 in porcine lymph samples, but low positive rates of 10.2% and 16.1% in oral swabs and rectal swabs, respectively. In conclusion, this study characterized a novel representative genome of a lymphotropic PAdV-B with unique evolutionary origin, which contributes to the taxonomical and pathogenic studies of PAdVs.

10.
Chin Med J (Engl) ; 133(8): 892-898, 2020 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-32187053

RESUMO

BACKGROUND: Despite the recent advances in treatments for rheumatoid arthritis (RA), there are still unmet needs in disease outcomes. This study aimed to analyze the satisfaction with drug therapies for RA according to the levels of disease severity (patient-assessed) and proportions of treatment cost to household income. METHODS: This was a subgroup study of a cross-sectional study in patients with RA and their physicians. The patients were subdivided into different subgroups based on their self-assessed severity of RA and on the proportions of treatment cost to household income (<10%, 10-30%, 31-50%, and >50%). The Treatment Satisfaction Questionnaire for Medication version II was used to assess patients' treatment satisfaction. RESULTS: When considering all medications, effectiveness, convenience, and global satisfaction scores were lower in the severe and moderate RA subgroups than those in the mild and extremely mild RA subgroups (all P < 0.001). Effectiveness, side effects, and convenience scores were higher in the <10% subgroup compared to those in the >50% subgroup (all P < 0.05). Global satisfaction score was higher in the <10% subgroup than that in the 31% to 50% subgroup (F = 13.183, P = 0.004). For biological disease-modifying anti-rheumatic drugs, effectiveness and convenience scores were lower in the severe RA subgroup than those in the extremely mild RA subgroup (both P < 0.05). Convenience score was higher in the <10% subgroup compared to that in the 31% to 50% and >50% subgroups (F = 12.646, P = 0.005). Global satisfaction score was higher in the <10% subgroup than that in the 31% to 50% subgroup (F = 8.794, P = 0.032). CONCLUSION: Higher disease severity and higher financial burden were associated with lower patient satisfaction.

11.
Environ Sci Pollut Res Int ; 27(12): 13617-13636, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32030589

RESUMO

CO pretreatment was found to effectively improve the SCR performance of CeO2, with over 90% at about 300 °C. The larger specific area and the decrease of CeO2 crystallization indicated the modification of the surface structure after CO pretreatment. Abundant Ce3+ species and active oxygen, better reducibility, and the higher surface adsorption capacity were mainly responsible for its enhanced SCR performance. DRIFT analysis revealed the presumed coexistence of two reaction routes that the L-H mechanism was related to the reaction temperature, while the reaction rate of E-R route was almost directly proportional to the NO concentration at a certain temperature, based on the kinetic calculation. In addition, the CO-pretreated CeO2 also exhibited a better poisoning tolerance for SO2 and H2O and excellent thermal stability and circularity. Graphical abstract The process of NH3-SCR reaction over CeO2-CO catalyst.


Assuntos
Amônia , Cério , Adsorção , Catálise , Temperatura
12.
J Autoimmun ; 108: 102404, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31952907

RESUMO

The chromatin modifier enhancer of zeste homolog 2 (EZH2) methylates lysine 27 of histone H3 (H3K27) and regulates T cell differentiation. However, the potential role of EZH2 in the pathogenesis of rheumatoid arthritis (RA) remains elusive. We analyzed EZH2 expression in PBMC, CD4+ T cells, CD19+ B cell, and CD14+ monocytes from active treatment-naïve RA patients and healthy controls (HC). We also suppressed EZH2 expression using EZH2 inhibitor GSK126 and measured CD4+ T cell differentiation, proliferation and apoptosis. We further examined TGFß-SMAD and RUNX1 signaling pathways in EZH2-suppressed CD4+ T cells. Finally, we explored the regulation mechanism of EZH2 by RA synovial fluid and fibroblast-like synoviocyte (FLS) by neutralizing key proinflammatory cytokines. EZH2 expression is lower in PBMC and CD4+ T cells from RA patients than those from HC. EZH2 inhibition suppressed regulatory T cells (Tregs) differentiation and FOXP3 transcription, and downregulated RUNX1 and upregulated SMAD7 expression in CD4+ T cells. RA synovial fluid and fibroblast-like synoviocytes suppressed EZH2 expression in CD4+ T cells, which was partially neutralized by anti-IL17 antibody. Taken together, EZH2 in CD4+ T cells from RA patients was attenuated, which suppressed FOXP3 transcription through downregulating RUNX1 and upregulating SMAD7 in CD4+ T cells, and ultimately suppressed Tregs differentiation. IL17 in RA synovial fluid might promote downregulation of EZH2 in CD4+ T cells. Defective EZH2 in CD4+ T cells might contribute to Treg deficiency in RA.

13.
Chem Commun (Camb) ; 56(11): 1669-1672, 2020 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-31939456

RESUMO

A new, general Pd/Cu-cocatalysed dicarbonylative benzannulation of 3-acetoxy-1,4-enynes with CO and silylboranes is described. The method utilizes CO as both a one-carbon (C1) unit and an external addition functional reagent to achieve an unprecedented dicarbonylative benzannulation process, and represents a facile, efficient route to 3-hydroxyarylacylsilanes. Mechanistically, the silyl-Cu intermediate formed from CuF2 and silylboranes, and silyl-Pd intermediate generated by transmetallation are two key factors for successfully targeting the reaction and selectivity.

14.
Clin Exp Rheumatol ; 37 Suppl 121(6): 52-57, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31573475

RESUMO

OBJECTIVES: As a rare systemic autoinflammatory disease, adult-onset Still's disease (AOSD) has heterogeneous clinical manifestations, response to treatment and outcome. This study tried to assess the clinical characteristics, laboratory tests, and treatments of Chinese AOSD patients, and make a retrospective analysis. METHODS: We collected from 7 hospitals in China a total of 517 Chinese patients with AOSD who satisfied the Yamaguchi criteria. We retrospectively evaluated their clinical features, laboratory tests, treatments and compared them with published data from different studies. All the data in this study were from medical records and further statistic analyses. RESULTS: We evaluated a total of 517 AOSD patients, 72% female, average age of onset was 37.7; spiking fever, rash and arthralgia occurred in 472 (91.3%), 413 (79.9%), 378 (73.1%) cases, respectively. There were 439/513 (85.6%) cases with leukocytosis and 456/476 (95.8%) cases with raised serum ferritin. The highest frequently used medications and regimens for remission were glucocorticoids (498/517, 96.3%), methotrexate (273/517, 52.8%) and hydroxychloroquine (174/517, 33.7%). 84.4%. 357/423 of AOSD cases were able to achieve initial remission with different regimens, mostly including glucocorticoids, methotrexate or hydroxychloroquine. 47.2% of them (244/517) received 30

Assuntos
Glucocorticoides/uso terapêutico , Prednisona/uso terapêutico , Doença de Still de Início Tardio , Adulto , China , Feminino , Humanos , Masculino , Indução de Remissão , Estudos Retrospectivos , Doença de Still de Início Tardio/diagnóstico , Doença de Still de Início Tardio/tratamento farmacológico , Doença de Still de Início Tardio/patologia , Inquéritos e Questionários
15.
Front Vet Sci ; 6: 235, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31403047

RESUMO

Fructus arctii, also known as great power seed, is the dried fruit of Arctium lappa of the family Compositae. It is a commonly used veterinary herbal medicine, and arctigenin is the main active ingredient. The aim of this study was to characterize the absorption, distribution, metabolism, and excretion of arctigenin and Fructus arctii powder in piglets. These data were used to provide a theoretical reference for the development and clinical use of new veterinary drugs. Sixteen healthy piglets (mean weight 30.0 ± 5.0 kg) were divided into two groups. One group was administered 2.0 mg/kg body weight (bw) arctigenin intravenously, and the other was administered 1.0 g/kg.bw Fructus arctii powder by gavage. Blood samples were collected from the anterior vena cava at different time points, and the concentration of arctigenin in the plasma of the piglets was determined using high-performance liquid chromatography (HPLC). Arctigenin conformed to a two-compartment model with no absorption, and the main pharmacokinetic parameters were as follows: distribution half-life (t 1/2α)-0.166 ± 0.022 h; elimination half-life (t 1/2ß)-3.161 ± 0.296 h; apparent volume of distribution (V d)-0.231 ± 0.033 L/kg; clearance rate (CLb)-0.057 ± 0.003 L/(h.kg); and area under the curve (AUC)-1.189 ± 0.057 g.h/mL. The pharmacokinetic parameters of arctigenin following oral administration of the Fructus arctii powder were as follows: absorption half-life (t 1/2ka)-0.274 ± 0.102 h, t 1/2α-1.435 ± 0.725 h, t 1/2ß-63.467 ± 29.115 h, V d-1.680 ± 0.402 L/kg, CLb-0.076 ± 0.028 L/(h kg), peak time (t max)-0.853 ± 0.211 h, peak concentration (C max)-0.430 ± 0.035 g/mL, and AUC-14.672 ± 4.813 g/mL. These results indicated that intravenous arctigenin was sparingly distributed in tissues. In contrast, orally administered Fructus arctii powder was rapidly absorbed, more widely distributed, and more slowly eliminated than the intravenous arctigenin, which may indicate its sustained pharmacological effects.

16.
World J Gastroenterol ; 25(16): 1913-1927, 2019 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-31086460

RESUMO

Understanding the occurrence, development, and treatment of liver diseases is the main goal of hepatopathology research. Liver diseases are not only diverse but also highly heterogeneous among individuals. At present, research on liver diseases is conducted mainly through cell culture, animal models, pathological specimens, etc. However, these methods cannot fully reveal the pathogenic mechanism and therapeutic characteristics of individualized liver diseases. Recent advances in three-dimensional cell culture technology (organoid culture techniques) include pluripotent stem cells and adult stem cells that are cultured in vitro to form self-organizing properties, making it possible to achieve individualized liver disease research. This review provides a comprehensive overview of the development of liver organoids, the existing and potential applications of liver regenerative medicine, the pathogenesis of liver disease heterogeneity, and drug screening.


Assuntos
Técnicas de Cultura de Células/métodos , Hepatopatias/terapia , Organoides/efeitos dos fármacos , Animais , Modelos Animais de Doenças , Avaliação Pré-Clínica de Medicamentos/métodos , Humanos , Fígado/citologia , Fígado/patologia , Hepatopatias/patologia , Medicina Regenerativa/métodos , Pesquisa Médica Translacional/métodos
17.
Clin Rheumatol ; 38(1): 107-115, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30123930

RESUMO

To estimate the mortality and describe the causes of death in a large multicenter cohort of hospitalized patients with SLE in China. This was a retrospective study of a nationwide SLE cohort (10 centers, 29,510 hospitalized patients) from 2005 to 2014 in China. Standardized mortality ratios (SMRs) were calculated for all death and were stratified by sex and age. Chi-square test was used to determine whether the major causes of death vary in age, sex, duration of SLE, disease activity, or medications. Comparison between dead patients and survival controls was used to identify the risk factors for mortality. Logistic regression analysis was used to evaluate the risk factors for mortality. A total of 360 patients died during the study period, accounting for 1.22%. The overall SMR was 2.13 (95% CI 1.96, 2.30), with a particularly high SMR seen in subgroups characterized by younger age. Infection (65.8%) was the most common cause of death, followed by lupus nephritis (48.6%), hematological abnormality (18.1%), neuropsychiatric lupus/NPSLE (15.8%), and interstitial pneumonia (13.1%). Cardiovascular disease and malignancy contributed little to the causes of death. Infection, in particular severe pulmonary infection, emerged as the foremost risk factor for mortality, followed by lupus encephalopathy. However, lupus nephritis and hematological abnormalities occurred more frequently in survival patients. SLE patients at a younger age of diagnosis have a poorer prognosis. Infection dominated the causes of death in recent China. Ethnicity and medications might account for the differences in causes of death compared with western populations.


Assuntos
Causas de Morte , Lúpus Eritematoso Sistêmico/mortalidade , Adolescente , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Doenças Cardiovasculares/complicações , Criança , China/epidemiologia , Feminino , Humanos , Infecções/complicações , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Neoplasias/complicações , Estudos Retrospectivos , Fatores de Risco , Distribuição por Sexo , Adulto Jovem
18.
Chirality ; 31(1): 11-20, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30417573

RESUMO

Anisodamine (654-1), a well-known cholinergic antagonist, is marketed as synthetic anisodamine (mixture of four isomers, 654-2) in China. To preparative resolution and comparison of the bioactivities of the four isomers of synthetic anisodamine, current work explores an economic and effective separation method by using preparative high performance liquid chromatography (HPLC) and diastereomer crystallization. Their absolute configurations were established by single-crystal X-ray diffraction and circular dichroism method. The purities of each isomer were more than 95%. Among them, 654-2-A2 (6R, 2'S configuration) exhibited better effect on cabachol preconditioned small intestine tension more than 654-2 and other isomers. The direct separation method without using HPLC was tried as well, which was still on progress. This is the first report of the method for preparative separation of four isomers of synthetic anisodamine which could be used for large-scale production in industry.

19.
Angew Chem Int Ed Engl ; 57(40): 13308-13312, 2018 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-30114326

RESUMO

A new palladium-catalyzed reductive [5+1] cycloaddition of 3-acetoxy-1,4-enynes with CO, enabled by hydrosilanes, has been developed for delivering valuable functionalized phenols. This methodology employs hydrosilanes as the external reagent to facilitate the [5+1] carbonylative benzannulation. The reaction is a conceptually and mechanistically novel carbonylative cycloaddition route for the construction of substituted phenols, through the formation of four new chemical bonds, with excellent functional-group tolerance.

20.
Virol Sin ; 33(3): 294, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29808439

RESUMO

The affiliation listed for Cecilia Waruhiu is incorrect. The byline and affiliation line should appear as shown above.

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