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1.
J Zhejiang Univ Sci B ; 20(11): 933-939, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31595730

RESUMO

Neuroendocrine neoplasms (NENs) are a heterogeneous group of tumors that arise from neuroendocrine cells, and in some cases are capable of producing agents that may cause characteristic hormonal syndromes (Cives and Strosberg, 2018). Such tumors were previously thought to be rare, but the rate of detection of NENs, especially from the gastrointestinal tract, is increasing with the widespread use of colonoscopy, cross-sectional imaging, and biomarkers (Gu et al., 2019). A study based on the Surveillance, Epidemiology, and End Results (SEER) database showed that the age-adjusted incidence of NENs increased 6.4-fold from 1973 (1.09 per 100 000) to 2012 (6.98 per 100 000) (Dasari et al., 2017), while there was a progressive increase in the incidence of colorectal NENs (Starzynska et al., 2017).

2.
Int Immunopharmacol ; 76: 105877, 2019 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-31522017

RESUMO

Acute lung injury (ALI) and/or acute respiratory distress syndrome (ARDS) are life-threatening critical syndromes characterized by the infiltration of a large number of inflammatory cells that lead to an excessive inflammatory response. Resolvin D1 (RvD1), an endogenous lipid mediator, is believed to have anti-inflammatory and proresolving effects. In the present study, we examined the impact of RvD1 on the pulmonary inflammatory response, neutrophil influx, and lung damage in a murine model of lipopolysaccharide (LPS)-induced ALI. Treatment with RvD1 protected mice against LPS-induced ALI, and compared to untreated mice, RvD1-treated mice exhibited significantly ameliorated lung pathological changes, decreased tumor necrosis factor-α (TNF-α) concentrations and attenuated neutrophil infiltration. In addition, treatment with RvD1 attenuated LPS-induced neutrophil infiltration via the downregulation of CXCL2 expression on resident alveolar macrophages. Finally, BOC-2, which inhibits the RvD1 receptor lipoxin A4 receptor/formyl peptide receptor 2 (ALX/FPR2), reversed the protective effects of RvD1. These data demonstrate that RvD1 ameliorates LPS-induced ALI via the suppression of neutrophil infiltration by an ALX/FPR2-dependent reduction in CXCL2 expression on resident alveolar macrophages.

3.
Mil Med ; 2019 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-31498402

RESUMO

INTRODUCTION: Leptospirosis is a global zoonotic disease spread through contact with contaminated water/soil. The US soldiers at the military bases in these countries are extremely vulnerable, as most of them are immunologically naïve to the responsible pathogen. No recent sero-epidemiological data of leptospirosis among US Marines stationed in Japan were available. MATERIALS AND METHODS: In this study, we analyzed the presence of leptospirosis in US Marines stationed in Japan. One thousand posttour sera samples were analyzed by enzyme-linked immunosorbent assay for Leptospira-specific Immunoglobulin G. RESULTS: Among these 1,000 posttour samples, 85 of them were positive and corresponding pretour samples were analyzed by enzyme-linked immunosorbent assay also. Seroconversion occurred for 35 (3.5%) Marines during their assignment to Japan. These results also indicate that 50 Marine personnels were exposed to leptospires before their assignment to Japan, perhaps because of previous exposure to leptospires at home. CONCLUSION: The 5% rate of seroconversion in 2013 and 2014 suggests that leptospirosis is a potential threat for Marines in the endemic region in Japan.

4.
Chin J Nat Med ; 17(8): 624-630, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31472900

RESUMO

Five new polyhydroxylated furostanol saponins were isolated from the roots and rhizomes of Tupistra chinensis, and their structures were determined as tupistrosides J-N (1-5), together with four known furostanol saponins (6-9), on the basis of physico-chemical properties and spectral analysis. Among them, compounds 3 and 5 showed cytotoxicity against human cancer cell lines SW620 with IC50 values of 72.5 ± 2.4 and 77.3 ± 2.5 µmol·L-1, respectively. Compound 4 showed cytotoxicity against human cancer cell line HepG2 with IC50 value of 88.6 ± 2.1 µmol·L-1.

5.
Artigo em Inglês | MEDLINE | ID: mdl-31520808

RESUMO

OBJECTIVES: The rapid spread of Klebsiella spp. is recognized as a major threat to public health owing to a rise in the number of both healthcare- and community acquired infections. Here we report the draft genome sequence of a high carbapenem-resistant strain Klebsiella quasipneumoniae subsp. quasipneumoniae Cln185 isolated from an HIV patient with pneumonia. METHODS: Classical microbiological methods were applied to isolate and identify the strain, genomic DNA was sequenced using an Illumina HiSeq platform and the reads were de novo assembled into contigs using CLC Genomics Workbench. The assembled contigs was annotated and whole genome sequencing (WGS) analysis was performed. RESULTS: WGS analysis revealed the genome comprised a circular chromosome of 5,406,774 bp with a G-C content of 57.73 %. Three important antibiotic resistance genes, IMP-38, OKP-B-6, and DHA-1, were detected. In addition, genes conferring resistance to aminoglycosides, macrolides, sulfonamide, fluoroquinolones, and tetracycline were also identified. CONCLUSION: The draft genome sequence reported herein will lay the foundation for future research for antibiotic resistance mechanisms and pathogenic mechanisms in Klebsiella quasipneumoniae subsp. quasipneumoniae, and also will promote the comparative analysis with genomic features among different sources of clinically important multidrug resistance strains.

6.
Ecotoxicol Environ Saf ; 184: 109593, 2019 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-31479760

RESUMO

Leaf vegetables have strong capabilities to take up cadmium (Cd) compared to other vegetable varieties. Until now, the differences in Cd uptake and accumulation by leaf vegetables from different families and genera and the related health risks were unknown. To remedy this, we studied 71 leaf vegetables (multiple genotypes within 17 categories of vegetables) in soil cultivation experiments (3 Cd treatment levels). Results showed that at 2.12 mg kg-1 Cd treatment, the dry weight of only five genotypic varieties from the families Brassicaceae and Asteraceae significantly decreased compared to the control, suggesting their weak Cd tolerances. Vegetables from the Brassicaceae, Asteraceae, Apiaceae, and Convolvulaceae families had stronger Cd absorption capabilities, whereas those from the Liliaceae and Amaranthaceae families had weaker ones. Cluster analysis found that the 17 vegetable categories could be divided into three groups: vegetables with high Cd accumulation capabilities were Lactuca sativa L.var. ramosa Hort. and Lactuca sativa var. longifoliaf. Lam. Vegetables with moderate Cd accumulation capabilities were bok choy, napa cabbage, choy sum, leaf mustard, Lactuca sativa L., Sonchus oleraceus L., celery, coriander, and water spinach. Vegetables with low Cd accumulation capabilities were cabbage, crown daisy, garlic chive, Allium ascalonicum, Gynura cusimbua, and edible amaranth. Estimated daily intake (EDI) and target hazard quotient (THQ) analysis results showed that 100% genotypes of vegetables from the Apiaceae and Convolvulaceae families had health risks; 100% genotypes of Lactuca sativa L., Sonchus oleraceus L., Lactuca sativa L. var. ramosa Hort., and Lactuca sativa var. longifoliaf. Lam from the Asteraceae family carried high risks. Of vegetables in the Brassicaceae family, 42.9% showed risks. Vegetables from the Amaranthaceae and Liliaceae families, Gynura cusimbua and crown daisy from the Asteraceae family, and cabbage from the Brassicaceae family all displayed relatively low risks (all 100%).

7.
FEBS Lett ; 2019 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-31541584

RESUMO

Protein arginine methyltransferase 1 (PRMT1) stimulates erythroid differentiation, but the signaling events upstream are yet to be identified. Ca2+ plays crucial roles during erythroid differentiation. Here, we show that Ca2+ enhances methylation during induced erythroid differentiation and that Ca2+ directly upregulates the catalytic activity of recombinant PRMT1 by increasing Vmax toward the substrate heterogeneous nuclear ribonucleoprotein A2. We demonstrate that PRMT1 is essential and responsible for the effect of Ca2+ on differentiation. Depletion of Ca2+ suppresses PRMT1-mediated activation of p38α and p38α-stimulated differentiation. Furthermore, Ca2+ stimulates methylation of p38α by PRMT1. This study uncovers a novel regulatory mechanism for PRMT1 by Ca2+ and identifies the PRMT1/p38α axis as an intracellular mediator of Ca2+ signaling during erythroid differentiation.

8.
Artigo em Inglês | MEDLINE | ID: mdl-31544273

RESUMO

A 78-year-old man presenting with amaurosis was admitted to the outpatient clinic 1 week ago. His baseline electrocardiogram showed Mobitz type II atrioventricular block and right bundle branch block. The patient's heart rate from Holter was only 32 bpm and therefore the indication for pacemaker implantation.

10.
G3 (Bethesda) ; 9(10): 3501-3511, 2019 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-31484671

RESUMO

Alternative oxidases (AOXs) are the terminal oxidase in the cyanide-resistant respiration pathway in plant mitochondria, which play an important role in abiotic stress and are proposed as a functional marker for high tolerant breeding. In this study, ten AOX genes (BnaAOXs) were identified, and CysI and CysII of AOX isoforms were highly conserved in rapeseed. Among them, Bna.AOX1b was mainly expressed in the ovule and displayed varying expression between rapeseed cultivars which showed different salt resistance in seed germination. We identified its mitochondrial localization of this gene. To investigate the function of BnaAOX1b in rapeseed, transgenic rapeseed lines with overexpressed BnaAOX1b were created and seed germination and seedling establishment assays were performed under osmotic, salt, and ABA treatment. The results indicated that overexpression of BnaAOX1b significantly improved seed germination under osmotic and salt stress and weakened ABA sensitivity. In addition, post-germination seedling growth was improved under high salt condition, but showed hypersensitivity to ABA. RNA-sequencing analysis indicated that the genes involved in electron transport or energy pathway were induced and a number of gene responses to salt stress and ABA were regulated in Bna.AOX1b overexpressing seeds. Taken together, our results imply that Bna.AOX1b confers tolerance to osmotic and salt stress in terms of seed germination and seedling establishment by regulating stress responsive genes and the response to ABA, and could be utilized as a candidate gene in transgenic breeding.

11.
Inorg Chem ; 58(19): 12832-12842, 2019 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-31490672

RESUMO

Rational synthesis of inorganic matter remains a great challenge encountered with modern synthetic chemistry. Here we reported the stepwise solvothermal conversion from GeO2 to [MGe4S10]n3n- (M = Cu, Ag) polymer via isolatable [Ge2S6]4- and [Ge4S10]4- anions by virtue of templating technique. The facile sulfuration of GeO2 resulted in the methylammonium-templated dimeric thiogermanate [CH3NH3]4Ge2S6 (1). This was used subsequently as a precursor for the formation of adamantane-like [Ge4S10]4- cluster, which was isolated as a mixed methylammonium/ethylammonium salt [CH3CH2NH3]3[CH3NH3]Ge4S10 (2). Compound 2 was then successfully used as a precursor to react with Cu+ and Ag+ cations in the presence of tetraethylammonium, resulting in alternating copolymeric products [(CH3CH2)4N]3MGe4S10 (M = Cu (3), Ag (4)), whose anionic moieties feature a novel zigzag chainlike structure constructed by [Ge4S10]4- clusters via two-coordinate Cu+/Ag+ linkers. Mixed amine/ethanol or deep eutectic solvents were applied as media for the syntheses of 1-4, and all the products were characterized in the solid state and solution. Crystal structural analysis of the title compounds revealed significant templating roles of the alkylammonium cations as both space-filling agents and hydrogen-bonding donors, suggesting the structure-directing mechanism for the species formation and crystal growth. The design and optimization of multistep structural conversion upon templating effects would be beneficial for drawing rational, predictable pathways for inorganic synthesis.

12.
Eur J Anaesthesiol ; 2019 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-31464712

RESUMO

BACKGROUND: Postoperative delirium (POD) has been confirmed as an important complication after major surgery. However, neurosurgical patients have usually been excluded in previous studies. To date, data on POD and risk factors in patients after intracranial surgery are scarce. OBJECTIVES: To determine the incidence and risk factors of POD in patients after intracranial surgery. DESIGN: Prospective cohort study. SETTING: A neurosurgical ICU of a university-affiliated hospital, Beijing, China. INTERVENTIONS: Adult patients admitted to the ICU after elective intracranial surgery under general anaesthesia were consecutively enrolled between 1 March 2017 and 2 February 2018. Delirium was assessed using the Confusion Assessment Method for the ICU. POD was diagnosed as Confusion Assessment Method for the ICU positive on either postoperative day 1 or day 3. Patients were classified into groups with or without POD. Data were collected for univariate and multivariate analyses to determine the risk factors for POD. RESULTS: A total of 800 patients were included. POD was diagnosed in 157 patients (19.6%, 95% confidence interval 16.9 to 22.4%). Independent risk factors for POD included age, nature of intracranial lesion, frontal approach craniotomy, duration of surgery, presence of an episode of low pulse oxygenation at ICU admission, presence of inadequate emergence and emergence delirium, postoperative pain and presence of immobilising events. POD was associated with adverse outcomes and high costs. CONCLUSION: POD is prevalent in patients after elective intracranial surgery. The identified risk factors for and the potential association of POD with adverse outcomes suggest that a comprehensive strategy involving screening for predisposing factors and early prevention of modifiable factors should be established in this population. TRIAL REGISTRATION: The study was registered at ClinicalTrials.gov (NCT03087838).

13.
Artigo em Inglês | MEDLINE | ID: mdl-31399835

RESUMO

With the rapid development of economy and society, the quality of groundwater is deteriorating under the dual influence of natural factors and anthropogenic factors, and it seriously threatens the safety of human drinking water. Identifying and analyzing the impact of anthropogenic activities is the key to solving this problem. Based on the groundwater problem in Changle County, Shandong Province, P.R. China, 43 groundwater samples were taken and tested. The statistical characteristics of the monitoring data, the groundwater chemical types, spatial distribution of groundwater, and influencing factors were analyzed by using enrichment factor, Mahalanobis distance, grey water footprint, and so on. The analysis results show that the overall water quality of Changle County is poor, and the main over-standard ions are Cl- , SO2- 4, and NO- 3. There is obvious spatial heterogeneity in the groundwater quality. The spatial variation of NO- 3 is affected by structural factors (topography, hydrology, etc.) and random factors (industrial, agricultural, etc.), and the spatial variability of NO- 3 is the most significant. Other water quality indicators are mainly affected by structural factors. The mass concentration of most ions decreases gradually from north to south, and the overall water quality in the southern region is better than that in the northern region. Thus, the supervision of chemical fertilizers and pesticides should be strengthened. The advanced treatment and reuse of wastewater from industrial parks should be promoted to improve the quality of groundwater and ensure the safety of human drinking water.

14.
Plant Biotechnol J ; 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31373135

RESUMO

Plant height and branch number are essential components of rapeseed plant architecture and are directly correlated with its yield. Presently, improvement of plant architecture is a major challenge in rapeseed breeding. In this study, we first verified that the two rapeseed BnaMAX1 genes had redundant functions resembling those of Arabidopsis MAX1, which regulates plant height and axillary bud outgrowth. Therefore, we designed two sgRNAs to edit these BnaMAX1 homologs using the CRISPR/Cas9 system. The T0 plants were edited very efficiently (56.30%-67.38%) at the BnaMAX1 target sites resulting in homozygous, heterozygous, bi-allelic and chimeric mutations. Transmission tests revealed that the mutations were passed on to the T1 and T2 progeny. We also obtained transgene-free lines created by the CRISPR/Cas9 editing, and no mutations were detected in potential off-target sites. Notably, simultaneous knockout of all four BnaMAX1 alleles resulted in semi-dwarf and increased branching phenotypes with more siliques, contributing to increased yield per plant relative to wild type. Therefore, these semi-dwarf and increased branching characteristics have the potential to help construct a rapeseed ideotype. Significantly, the editing resources obtained in our study provide desirable germplasm for further breeding of high yield in rapeseed.

15.
Nat Commun ; 10(1): 3561, 2019 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-31395892

RESUMO

Protein corona presents a major obstacle to bench-to-bedside translation of targeted drug delivery systems, severely affecting targeting yields and directing unfavorable biodistribution. Corona-mediated targeting provides a new impetus for specific drug delivery by precisely manipulating interaction modes of functional plasma proteins on nano-surface. Here bio-inspired liposomes (SP-sLip) were developed by modifying liposomal surface with a short nontoxic peptide derived from Aß1-42 that specifically interacts with the lipid-binding domain of exchangeable apolipoproteins. SP-sLip absorb plasma apolipoproteins A1, E and J, consequently exposing receptor-binding domain of apolipoproteins to achieve brain-targeted delivery. Doxorubicin loaded SP-sLip (SP-sLip/DOX) show significant enhancement of brain distribution and anti-brain cancer effect in comparison to doxorubicin loaded plain liposomes. SP-sLip preserve functions of the absorbed human plasma ApoE, and the corona-mediated targeting strategy works in SP modified PLGA nanoparticles. The present study may pave a new avenue to facilitate clinical translation of targeted drug delivery systems.

16.
Biosens Bioelectron ; 142: 111504, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31401226

RESUMO

The wide cultivation of genetically modified (GM) crops has raised concerns on the risks to humans and the environment. 5-enolpyruvylshikimate-3-phosphate synthase isolated from Agrobacterium species strain CP4 (CP4-EPSPS) protein is most widely present in these crops. Therefore the measurement of CP4-EPSPS sensitively in a point-of-care testing (POCT) manner for the screening of transgenic plants is demanded. To date the development of quantitative POCT system has not yet been reported. In presented study, an electrochemical immunosensor towards CP4-EPSPS has been fabricated by integrating a portable bioanalytical device with a disposable screen-printed carbon electrode (SPCE) for POCT of GM crops. The dual-functionalized AuNPs were used as nanoprobes and prepared by simultaneously tagging horseradish peroxidase (HRP) and antibody on AuNPs with an exceptionally simple protocol. The sensitivity of the developed nanoprobe-based immunosensor was 62.5-fold higher than that using HRP-labeled antibody. As a result, the proposed immunosensor using SPCE could detect CP4-EPSPS down to 0.050 ng mL-1 with the linear range of 0.10-10 ng mL-1 within 65 min. In addition, the developed method has been validated with genuine GM crops and the results show a good correlation coefficient of 0.9909 compared with those of a commercial ELISA kit. Therefore, this portable electrochemical immunosensor is suitable for rapid and sensitive detection and provides a convenient and reliable platform for POCT assay.

17.
J Cardiovasc Electrophysiol ; 30(10): 2164-2169, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31456266

RESUMO

BACKGROUND: His bundle pacing (HBP) is a physiological pacing modality, but HBP implantation remains a challenge. OBJECTIVE: This study explored the feasibility of using visualization of the tricuspid valve annulus (TVA) to locate the site for HBP. METHODS: During the lead placement in eight patients with symptomatic bradycardia, the TVA and tricuspid septal leaflet was revealed by contrast injection in the right ventricle under the fluoroscopic right anterior oblique view, and the target site for HBP was identified near the intersection of the tricuspid septal leaflet and the interventricular septum. On the basis of the imaging marker, the pacing lead was placed for HBP at either the atrial (aHBP) or ventricular side (vHBP). RESULTS: During the implantation, the pacing lead placement was attempted for aHBP in two patients, vHBP in five patients, and first for aHBP then vHBP in one patient. The aHBP was selective and had a capture threshold of 1.6 ± 0.5 V@ 1.0ms and R-wave amplitude of 1.2 ± 0.4 mV. Ventricular-side His bundle capture was selective in four patients and nonselective in two patients. The vHBP capture threshold was 0.8 ± 0.4 V@ 1.0ms (P < .05 vs aHBP) and R-wave amplitude was 4.1 ± 1.5 mV (P < .05 vs aHBP). At the final pacing programming of 3.0 V@ 1.0ms, vHBP was nonselective in all six patients and aHBP remained selective in two patients. Pacing parameters remained stable at 3 months. CONCLUSION: The location of the TVA and tricuspid septal leaflet revealed by right ventriculography can be used as a landmark to identify the HBP site.

19.
Anal Chem ; 91(15): 9424-9429, 2019 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-31313917

RESUMO

Single-domain antibodies (sdAb), recombinantly produced variable heavy domains derived from the unconventional heavy chain antibodies found in camelids, provide stable, well-expressed binding elements with excellent affinity that can be tailored for specific applications through protein engineering. Complex matrices, such as plasma and serum, can dramatically reduce assay sensitivity. Thus, to achieve highly sensitive detection in complex matrices a highly efficient assay is essential. We produced sdAb as genetically linked dimers, and trimers, each including SpyTag at their C-terminus. The constructs were immobilized onto dyed magnetic microspheres to which SpyCatcher had been coupled and characterized in terms of their performance as capture reagents in sandwich assays. Initial tests on the ability of oriented monomer, dimer, and trimer captures to improve detection versus unoriented constructs in an assay for staphylococcal enterotoxin B spiked into buffer showed the oriented dimer format provided the best sensitivity while offering robust protein production. Thus, this format was utilized to improve a sdAb-based assay for the detection of dengue virus (DENV) nonstructural protein 1 (NS1) in serum. Detection of NS1 from each of the four DENV serotypes spiked into 50% normal human serum was increased by at least a factor of 5 when using the oriented dimer capture. We then demonstrated the potential of using the oriented dimer capture to improve detection of NS1 in clinical samples. This general method should enhance the utility of sdAb incorporated into any diagnostic assay, including those for high consequence pathogens.

20.
Nanoscale ; 11(29): 13720-13724, 2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31298678

RESUMO

Charge transport is strongly suppressed by destructive quantum interference (DQI) in meta-connected 1,1'-biphenyl-containing molecules, resulting in low electrical conductance. Surprisingly, we have found that DQI is almost entirely overcome by adding a bridging carbonyl, to yield a cross-conjugated fluorenone. This contrasts with other π-systems, such as para-connected anthraquinone, where cross-conjugation results in low conductance.

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