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1.
J Nanosci Nanotechnol ; 20(3): 1375-1382, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31492297

RESUMO

This work reports the synthesis, radiolabeling and imaging studies of iodine-124 labeled peptide modified gold nanoclusters (AuNCs) as positron emission tomography (PET) tracer for lung cancer. The novel modified Au nanoclusters were successfully synthesized by conjugation of tumortargeting peptide luteinizing hormone releasing hormone (LHRH) to human serum albumin (HAS) as a scaffold, resulting in 73% labeling yield of 124I-LHRH-HSA AuNCs. After rapid purification, the radiochemical purity was above 98%. Dynamic PET study in normal rats showed high liver accumulation and rapid lung clearance. Both the PET and fluorescence imaging in A549 xenografted tumor model demonstrated certain amount of tumor uptake. In orthotopic lung cancer model, the tumor sites could be clearly visualized between 2 to 5 hours in PET images. The higher radioactivity concentration in the left lung which inoculated orthotopic tumor than right lung also exhibited the targeting properties. The biological properties of this iodine-124 labeled nanoclusters afford potential applications for early diagnosis of lung cancer with PET.

2.
J Nanosci Nanotechnol ; 20(3): 1447-1453, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31492306

RESUMO

In present work, a novel Nd@TiO2 Nanocomposite, synthesized successfully by a facile sol-gel method, reveals significant light-activated antibacterial activity. The X-ray diffraction (XRD), Raman spectroscopy and transmission electron microscopy (TEM) show the anatase phase and globular shape of Nd@TiO2. UV-vis diffuse reflectance spectroscopy and low temperature N2 adsorption (BET) indicate Nd0.02@TiO2 has the narrow band gap (3.0 eV) and a high specific surface area (121.1 m2·g-1). Furthermore, the prepared Nd@TiO2 exhibits unprecedented higher photocatalytic activity than P25 TiO2. In water, Nd@TiO2 has higher inactivation against Escherichia coli (E. coli) bacteria under simulated solar light irradiation 70 min than TiO2, and the highest antibacterial efficiency (91.5%) of E. coli was achieved on Nd0.02@TiO2.

3.
Eur J Pharmacol ; : 172715, 2019 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-31593687

RESUMO

Non-alcoholic steatohepatitis (NASH) is a key step in the progression of non-alcoholic fatty liver disease (NAFLD), which causes serious health problems worldwide. The nucleotide-binding oligomerization domain, leucine-rich repeat-containing receptor-containing pyrin domain 3 (NLRP3) inflammasome and pyroptosis play crucial roles in the progression of NASH. Our team has provided clinical evidence of the effects of glucagon-like peptide-1 (GLP-1) on the improvement in liver function and histological resolution of NAFLD. Preliminary work has demonstrated that GLP-1 inhibited NLRP3 inflammasome activation in a mouse model of NAFLD. We further explored the potential molecular mechanisms underlying the anti-inflammatory effect of liraglutide, a long-acting GLP-1 analog, in the treatment of NASH. We established a HepG2 cell model of NASH using double stimulation with palmitic acid and lipopolysaccharide to assess NLRP3 inflammasome and pyroptotic cell activity and to evaluate mitochondrial function and mitophagy. Liraglutide reduced lipid accumulation, inhibited NLRP3 inflammasome and pyroptosis activation, attenuated mitochondrial dysfunction and reactive oxygen species generation, augmented mitophagy in hepatocytes. Mitophagy inhibition with 3-methyladenine/PINK1-directed siRNA weakened the liraglutide-mediated suppression of inflammatory injury. We propose that liraglutide suppresses NLRP3 inflammasome-induced hepatocyte pyroptosis via mitophagy to slow the progression of NASH.

4.
Cancer Biomark ; 2019 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-31594211

RESUMO

BACKGROUND: Hepatocellular carcinoma (HCC) is the sixth most common malignant tumor and second most common cause of tumor-related deaths worldwide. Activated platelets play a prominent role in tumor. Platelet distribution width (PDW) indicates platelets activation and is altered in malignancies. The aim of this study was to explore the prognostic value of PDW for overall survival (OS) in HCC patients. METHODS: We retrospectively reviewed 273 HCC patients at a single institution from 2010 to 2014. The relationship between PDW and clinicopathological characteristics was analyzed. Kaplan-Meier curves and multivariate Cox regression analyses were used to evaluate the relationship of PDW with OS. RESULTS: Low PDW levels were observed in 127 (46.5%) out of 273 patients. A significant correlation was found between PDW and liver cirrhosis. Median follow-up was 36 months, survival curves revealed that the patients with increased PDW had significantly shorter survival time than those with normal PDW (p= 0.001). Cox regression analysis demonstrated that PDW was an independent prognostic factor for overall survival (hazard ratio, 2.464; 95% confidence interval [CI], 1.402-4.330, p= 0.001). CONCLUSION: PDW is significantly associated with OS in HCC. This result suggests activated platelet may affect clinical outcome and warrant continued investigation.

5.
J Agric Food Chem ; 2019 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-31595753

RESUMO

Salvianolic acid A (Sal A) has a wide range of pharmacological activities. To date, there has been no systematic and detailed metabolite research data of Sal A after oral administration in vitro and in vivo. In this study, a rapid and systematic method based on ultra fast liquid chromatography-quadrupole-time-of-flight mass spectrometry (UFLC-Q/TOF-MS) was developed to detect metabolites of Sal A in vitro (human liver microsome, human intestinal microbiota, artificial gastric and intestinal juice) and in vivo (urine, plasma, feces and various organs collected after oral administration of Sal A to normal rats and pseudo-germ-free rats). A total of 26 metabolites of Sal A were characterized. These metabolites were formed through extensive metabolic reactions, such as hydroxylation, hydrogenation, and glucuronidation reactions. This study provides novel possibility for exploring the potential biological mechanism of Sal A, and aids the promotion of clinical application.

6.
J Clin Sleep Med ; 15(10): 1411-1420, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31596205

RESUMO

STUDY OBJECTIVES: Reliable sleep staging is difficult to obtain from home sleep testing for diagnosis of obstructive sleep apnea (OSA), especially when it is self-applied. Hence, the current study aimed to develop a single frontal electroencephalography-based automatic sleep staging system (ASSS). METHODS: The ASSS system was developed on a clinical dataset, with a high percentage of participants with OSA. The F4-M1 signal extracted from 62 participants (62.9% having OSA) was used to build a four-stage classifier. Performance of the ASSS was tested in a holdout set of 58 patients (60.3% having OSA) with epoch-by-epoch and whole-night agreement for sleep staging compared with expert scoring of polysomnography. RESULTS: Mean all-stage percentage agreement was 75.52% (95% confidence interval, 72.90 to 78.13) (kappa 0.62; 95% confidence interval, 0.58 to 0.65), with mean percentage agreement for wake, light sleep, deep sleep (DS), and rapid eye movement of 78.04%, 70.97%, 83.65%, and 75.00%, respectively. The whole-night agreement was good-excellent (intraclass correlation coefficient, 0.74 to 0.88) for sleep onset latency, wake after sleep onset, total sleep time, and sleep efficiency. Compared to the non-OSA subset, the OSA subset had lower agreement for DS. CONCLUSIONS: Our results indicate that a single-channel F4-M1 based ASSS was sufficient for sleep staging in a population with a high percentage of participants with OSA.

7.
Artigo em Inglês | MEDLINE | ID: mdl-31583814

RESUMO

Covalent-organic frameworks (COFs) as porous crystalline materials show promising application potentials. However, developing facile strategies for the construction of COFs directly from amorphous covalent organic polymers (COPs) is still a great challenge. To this end, we report a novel approach for easy preparation of COFs from amorphous COPs through the linkage replacement under different types of reactions, where four COFs with high crystallinity and porosity were constructed via the linkage substitution of polyimide-linked COPs to imine-linked COFs as well as imine-linked COPs to polyimide-linked COFs. The realization of the linkage substitution would significantly expand the research scope of COFs.

8.
Artigo em Inglês | MEDLINE | ID: mdl-31567082

RESUMO

Tiled modular 2D ultrasound arrays have the potential for realizing large apertures for novel diagnostic applications. This work presents an architecture for fabrication of tileable 2D array modules implemented using 1-3 composites of high bandwidth PIN-PMN-PT single crystal piezoelectric material closely coupled with high voltage CMOS Application Specific Integrated Circuit (ASIC) electronics for buffering and multiplexing functions. The module, which is designed to be operated as a λ-pitch 1.75D array, benefits from an improved electromechanical coupling coefficient and increased Curie temperature and is assembled directly on top of the ASIC silicon substrate using an interposer backing. The interposer consists of a novel 3D printed acrylic frame that is filled with conducting and acoustically absorbing silver epoxy material. The ASIC comprises a high voltage switching matrix with locally integrated buffering and is interfaced to a Verasonics Vantage 128, using a local FPGA controller. Multiple prototype 5 × 6 element array modules have been fabricated by this process. The combined acoustic array and ASIC module was configured electronically by programming the switches to operate as a 1D array with elements grouped in elevation for imaging and pulse-echo testing. The resulting array configuration had an average center frequency of 4.55 MHz, azimuthal element pitch of 340 #gm, and exhibited average -20dB pulse-width of 592 ns, and average -6dB fractional bandwidth of 77%.

9.
Ann Thorac Surg ; 2019 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-31589853

RESUMO

BACKGROUND: Upper hemisternotomy (UHS) tends to be performed for aortic valve replacement. However, the safety of UHS for total arch replacement combined with frozen elephant trunk implantation (FET) in patients with acute Type A dissections is ambiguous. METHODS: We retrospectively analyzed 162 consecutive patients with acute Type A dissections who underwent total arch replacement combined with FET between May 2016 and April 2018. 153 patients enrolled were included and divided into UHS group (n = 73, single upper hemisternotomy) and FS group (n = 80, full sternotomy). Perioperative characteristics were recorded. RESULTS: There was no significant difference in any of the pre and intra operative variables between two groups. However, ventilation times [18 (12-303) h vs. 20.5 (3-244) h, p = 0.002] were significantly shorter in the UHS group compared with the FS group. The first 24h [160 (70-700) ml vs. 267.5 (10-1455) ml, p = 0.001] chest tube drainage were significantly less in UHS group than in FS group. CONCLUSIONS: Total arch replacement combined with frozen elephant trunk implantation via single upper hemisternotomy approach in patients with acute Type A dissections is a safe procedure, which adds the benefit of a more cosmetic incision.

10.
Biomolecules ; 9(10)2019 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-31590330

RESUMO

This meta-analysis aimed to systematically review the evidence on cancer risk of the MMP-8 rs11225395 promoter polymorphism. Relevant studies published by 12 June 2019 were identified by systematically searching PubMed, Web of Science, Cochrane Library, CNKI and Wanfang databases. R programs and STATA software were used to calculate odds ratio (OR) and 95% confidence interval (CI). In total, 7375 cancer samples and 8117 controls were included by integrating 15 case-control data sets. Pooled estimates from the statistical analysis revealed no statistical significance for the association between this polymorphism and cancer risk. All pooled estimates resulting from subgroup analyses by cancer type and sample size were not materially altered and did not draw significantly different conclusions. The stratified analyses according to geographic region showed the statistical significance for increased cancer risk of the MMP-8 rs11225395 polymorphism in non-Asian populations under the allele model (OR = 1.11, 95% CI: 1.04-1.19), homozygote model (OR = 1.22, 95% CI: 1.05-1.41), heterozygote model (OR = 1.21, 95% CI: 1.07-1.36), and dominant model (OR = 1.21, 95% CI: 1.08-1.35). However, no statistical significance was detected in Asian populations. In conclusion, these findings suggested that the MMP-8 rs11225395 polymorphism is associated with elevated susceptibility to cancer in non-Asian populations.

11.
Biomed Pharmacother ; 120: 109500, 2019 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-31600641

RESUMO

OBJECTIVES: Findings from prior investigations show that left stellate ganglion (LSG) inhibitory approaches protect the heart from ventricular arrhythmias (VAs) caused by acute myocardial infarction (AMI), which still remain many side effects. Targeted transient receptor potential vanilloid 1/tyrosine hydroxylase (TRPV-1/TH) expressing sympathetic neurons ablation is a novel neuro-ablative strategy. The aim of this investigation was to explore if targeted molecular neuro-ablative strategy by resiniferatoxin (RTX) stellate microinjection could protect against ischemia-induced VAs. METHODS: Twenty-four anesthetized beagles were assigned to a control group (n = 12) and RTX group (n = 12) in a random manner. Targeted molecular neuro-ablative was produced by RTX stellate microinjection and DMSO was microinjected into LSG in the same way as control. Plasma norepinephrine (NE) level, heart rate variability (HRV), Tpeak-Tend interval (Tp-Te), LSG neural activity and function, ventricular effective refractory period (ERP), beat-to-beat variability of repolarization (BVR) and ventricular action potential duration (APD) were measured at baseline and 60 min after RTX or DMSO microinjection. AMI model was established by the ligation of left anterior descending coronary artery and 60-minute electrocardiography was continuously recorded for VAs analysis. Subsequently, HRV, Tp-Te, plasma NE level from jugular vein and coronary sinus, LSG neural activity and function, ventricular ERP, ventricular APD, BVR, action potential duration alternans (APDA) cycle length and ventricular fibrillation threshold (VFT) were evaluated after AMI. Finally, tissue collection of LSG was performed for examining the TRPV-1, nerve growth factor (NGF) protein and c-fos protein. RESULTS: TRPV-1 was highly expressed in the TH-expressing neurons and RTX injection significantly ablated TRPV-1/TH-positive neurons in LSG. Compared with baseline, RTX stellate microinjection significantly reduced plasma NE level, the sympathetic component of HRV, LSG neural activity and LSG function, shortened Tp-Te, prolonged ventricular ERP and APD, but there were no remarkable differences existed for control group. AMI resulted in the significant raise in plasma NE level from jugular vein and coronary sinus, the sympathetic component of HRV, LSG neural activity and LSG function, the marked prolongation in Tp-Te and BVR, the significant decrease in ERP and APD from ischemia area, and the increase in APDA cycle length in the ischemic region of the control group, which were remarkably attenuated in the RTX group. RTX pretreatment markedly rose the VFT in the RTX group. Furthermore, the AMI-triggered VAs was significantly prevented by RTX injection in the RTX group. RTX microinjection down-regulated significantly TRPV-1, NGF and c-fos expression in the LSG compared with the control group. CONCLUSION: Targeted ablation of TRPV-1/TH positive sympathetic neurons induced by RTX stellate microinjection could suppress ischemia-induced cardiac autonomic imbalances and cardiac electrophysiology instability to protect against AMI-induced VAs.

12.
Bioorg Chem ; 93: 103328, 2019 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-31600664

RESUMO

A series of new 4-N-phenylaminoquinoline derivatives were designed, synthesized, and their anticholinesterase activities, 1,1-Diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity, metal-chelating ability were tested. Among them, compounds 11j, 11k and 11l had comparable inhibition activities to reference drug galantamine both in AChE and in BChE. Especially, compound 11j revealed the most potent inhibition to eeAChE and eqBChE with IC50 values of 1.20 µM and 18.52 µM, respectively. Furthermore, both kinetic analysis of AChE inhibition and molecular docking study indicated that compound 11j was mixed-type inhibitor, binding simultaneously to the catalytic anionic site (CAS) and the peripheral anionic site (PAS) of AChE, and propidium iodide displacement assay showed significant displacement of propidium iodide with compound 11k (25.80%) from PAS of eeAChE. More importantly, compound 11l displayed excellent DPPH radical scavenging activity (84% at 1 mg/mL), and its EC50 value was 0.328 µM. In addition, compounds 11a, 11j, 11k and 11l exhibited obvious biometal chelating abilities toward Al3+, Fe2+, Cu2+ and Zn2+ ions. Taken together, 4-N-phenylaminoquinoline derivatives targeting multiple pathogenetic factors deserve further investigation for treatment of AD.

13.
Int J Mol Sci ; 20(20)2019 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-31600974

RESUMO

Several physiological processes, including cellular growth, embryonic development, differentiation, metabolism and proliferation, are modulated by genomic and nongenomic actions of thyroid hormones (TH). Several intracellular and extracellular candidate proteins are regulated by THs. 3,3,5-Triiodo-L-thyronine (T3) can interact with nuclear thyroid hormone receptors (TR) to modulate transcriptional activities via thyroid hormone response elements (TRE) in the regulatory regions of target genes or bind receptor molecules showing no structural homology to TRs, such as the cell surface receptor site on integrin αvß3. Additionally, L-thyroxine (T4) binding to integrin αvß3 is reported to induce gene expression through initiating non-genomic actions, further influencing angiogenesis and cell proliferation. Notably, thyroid hormones not only regulate the physiological processes of normal cells but also stimulate cancer cell proliferation via dysregulation of molecular and signaling pathways. Clinical hypothyroidism is associated with delayed cancer growth. Conversely, hyperthyroidism is correlated with cancer prevalence in various tumor types, including breast, thyroid, lung, brain, liver and colorectal cancer. In specific types of cancer, both nuclear thyroid hormone receptor isoforms and those on the extracellular domain of integrin αvß3 are high risk factors and considered potential therapeutic targets. In addition, thyroid hormone analogs showing substantial thyromimetic activity, including triiodothyroacetic acid (Triac), an acetic acid metabolite of T3, and tetraiodothyroacetic acid (Tetrac), a derivative of T4, have been shown to reduce risk of cancer progression, enhance therapeutic effects and suppress cancer recurrence. Here, we have reviewed recent studies focusing on the roles of THs and TRs in five cancer types and further discussed the potential therapeutic applications and underlying molecular mechanisms of THs.

14.
J Nucl Med ; 2019 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-31601698

RESUMO

Purpose: We aimed to assess the value of 11C-choline positron emission tomography (PET) in patients with primary hyperparathyroidism (pHPT) with negative or discordant results in methoxyisobutylisonitrile (MIBI) imaging and neck ultrasound. Methods: Eighty-seven patients with pHPT and negative or discordant neck ultrasound and MIBI single photon emission computed tomography/computed tomography (SPECT/CT) were assessed using 11C-choline PET/CT and subsequently received a parathyroidectomy. PET/CT image data were analysed semi-quantitatively using maximum standardised uptake value (SUVmax) and ratios (target to the contralateral thyroid gland and carotid artery). A positive PET/CT was defined as a focal uptake significantly higher than regular thyroid tissue. Ectopic foci were also considered to be positive. Inconclusive PET/CT cases were defined as a lesion with uptake equal to normal thyroid tissue. If no prominent or ectopic uptake was detectable, the PET/CT was considered be negative. Results: When dichotomizing the 11C-choline PET/CT imaging results by defining lesions with both positive and inconclusive uptake as positive, 84 of 92 lesions (91.3%) were found to have true-positive uptake versus 8 lesions (8.7%) with false-positive uptake. One lesion showed a false-negative uptake; sensitivity was 98.8%. The corresponding lesioned positive predictive value was 91.3%. The mean SUVmax was 6.15±4.92 in 72 lesions with positive uptake (70 patients); and mean SUVmax was 2.96±2.32 in 20 lesions with inconclusive uptake (18 patients). Conclusion: These results in a large group of patients indicate that11C-choline PET/CT is a promising tool for PTA localisation, in cases in which ultrasound and MIBI imaging yield negative or discordant results.

15.
Zhongguo Zhong Yao Za Zhi ; 44(16): 3512-3519, 2019 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-31602916

RESUMO

The aim of this paper was to systematically evaluate the toxicity-reducing effect of Tripterygium-licorice in animal experiments,and also to provide evidence for basic research on the toxicity reduction of Tripterygium wilfordii. The PubMed,EMbase,Web of Science,CBM,CNKI and Wan Fang Databases from their establishment to August 31 th,2018 were searched. Two independent reviewers screened the papers,extracted the data,assessed the risk of bias using SYRCLE assessment tool and conducted Meta-analysis with Rev Man 5. 3 software. A total of 10 papers involving 31 studies were finally included,15 studies of which were used for Meta-analysis. Four studies were included for chronic hepatotoxicity animal model. In experimental group( 34 animals),Tripterygium was administered at dose of 0. 09-0. 1 mg·kg-1·d-1,and glycyrrhizic acid was administered at dose of 90-100 mg·kg-1,both for 2 weeks; in control group( 34 animals),glycyrrhizic acid was replaced with equal volume of normal saline. Eleven studies were included for acute hepatotoxicity animal model. In experimental group( 66 animals),glycyrrhizic acid was administered at dose of 75-480 mg·kg-1 for 7 days,then glycyrrhizic acid was stopped,and Tripterygium began to be administered at dose of 0. 6-1. 0 mg·kg-1 per 24 h or 48 h for a total of 1-2 times; in control group( 66 animals),glycyrrhizic acid was replaced with equal volume of normal saline or corresponding solvent. The results of Meta-analysis showed that in both chronic hepatotoxicity animal model and acute hepatotoxicity animal model,the transaminase levels in the experimental group were lower than those in the control group( P < 0. 05). Subgroup analysis of acute hepatotoxicity animal model showed that the transaminase levels in the experimental group were lower than those in the control group for every subgroup except " glycyrrhizic acid 75 mg·kg-1" subgroup. However,in terms of the mean difference( MD) and confidence interval( CI),there was no significant difference in transaminase decline between each subgroup. Low dose of glycyrrhizic acid( 90-100 mg·kg-1) has a toxicity-reduction effect on chronic hepatotoxicity induced by tripterygium( 0. 09-0. 10 mg·kg-1). Middle and high doses of glycyrrhizic acid( 120-480 mg·kg-1) have a toxicity-reduction effect on acute hepatotoxicity induced by tripterygium( 0. 6-1. 0 mg·kg-1),but with no significant dose-effect relationship.

16.
Zhongguo Zhong Yao Za Zhi ; 44(17): 3684-3694, 2019 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-31602940

RESUMO

Pistacia lentiscus,which belongs to foreign medicine resources,is widely distributed in the Mediterranean and Middle Eastern area. The essential oils are a mixture of several volatile compounds mainly monoterpenes and sesquiterpenes obtained from different parts of P. lentiscus by hydrodistillation. The variability of chemical composition,biological activities and content of essential oil is strongly affected by extraction technology,environmental and sex factors. It is indicated that essential oils of P. lentiscus have kinds of biological activities such as antibacterial,anticancer,anti-atherogenesis,antioxidant,anti-inflammatory and insecticidal activities.Many scholars hold the opinion that combination of different components with synergistic and/or additive actions should account for their biological activities. Due to its diverse efficacy and special taste,the essential oil of P. lentiscus has been extensively used in medicine,food and cosmetics industries. A mini review of chemical constituents and biological activities of essential oil of P. lentiscus in the past20 years is made here to provide valuable reference for the construction of " the Belt and Road".

17.
Environ Sci Technol ; 2019 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-31603332

RESUMO

Rice ingestion has been recognized as an important route of dietary exposure to neurotoxic methylmercury (MeHg) that is commonly synthesized in rice paddy soils. Although Hg methylators are known to regulate soil MeHg formation, the effect of non-Hg methylating communities on MeHg production remains unclear. Here, we collected 141 paddy soil samples from main rice-producing areas across China to identify associations between bacterial community composition (including both Hg and putative non-Hg methylators) and MeHg production. Results showed that the MeHg content in the paddy soils varied from 0.11 to 8.36 ng g-1 at a national spatial scale, which could be owing to the shifts of soil microbial community composition across different areas. Our structure equation modelling suggested a strong link between bacterial community composition and MeHg content and %MeHg. More importantly, random forest analyses suggested a more significant role of putative non-Hg methylators than Hg methylators in predicting variations of soil MeHg content. The relative abundance of putative non-Hg methylators such as unclassified Xanthomonadales and Chitinophagaceae were strongly correlated with soil MeHg contents. Further, microbial network analysis revealed strong co-occurrence patterns between putative the non-Hg and Hg methylators. These findings highlight an overlooked role of non-Hg methylating communities in predicting MeHg production in paddy soils.

18.
PLoS One ; 14(10): e0222706, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31581225

RESUMO

Exploration and exploitation are contradictory in differential evolution (DE) algorithm. In order to balance the search behavior between exploitation and exploration better, a novel self-adaptive dual-strategy differential evolution algorithm (SaDSDE) is proposed. Firstly, a dual-strategy mutation operator is presented based on the "DE/best/2" mutation operator with better global exploration ability and "DE/rand/2" mutation operator with stronger local exploitation ability. Secondly, the scaling factor self-adaption strategy is proposed in an individual-dependent and fitness-dependent way without extra parameters. Thirdly, the exploration ability control factor is introduced to adjust the global exploration ability dynamically in the evolution process. In order to verify and analyze the performance of SaDSDE, we compare SaDSDE with 7 state-of-art DE variants and 3 non-DE based algorithms by using 30 Benchmark test functions of 30-dimensions and 100-dimensions, respectively. The experiments results demonstrate that SaDSDE could improve global optimization performance remarkably. Moreover, the performance superiority of SaDSDE becomes more significant with the increase of the problems' dimension.

19.
J Nanobiotechnology ; 17(1): 102, 2019 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-31581945

RESUMO

Natural extracellular matrices (ECMs) are three-dimensional (3D) and multi-scale hierarchical structure. However, coatings used as ECM-mimicking structures for osteogenesis are typically two-dimensional or single-scaled. Here, we design a distinct quasi-three-dimensional hierarchical topography integrated of density-controlled titania nanodots and nanorods. We find cellular pseudopods preferred to anchor deeply across the distinct 3D topography, dependently of the relative density of nanorods, which promote the osteogenic differentiation of osteoblast but not the viability of fibroblast. The in vivo experimental results further indicate that the new bone formation, the relative bone-implant contact as well as the push-put strength, are significantly enhanced on the 3D hierarchical topography. We also show that the exposures of HFN7.1 and mAb1937 critical functional motifs of fibronectin for cellular anchorage are up-regulated on the 3D hierarchical topography, which might synergistically promote the osteogenesis. Our findings suggest the multi-dimensions and multi-scales as vital characteristic of cell-ECM interactions and as an important design parameter for bone implant coatings.

20.
New Phytol ; 2019 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-31596964

RESUMO

• Wood (secondary xylem) formation in tree species is dependent on auxin-mediated vascular cambium activity in stems. However, the complex regulatory networks underlying xylem formation remain elusive. • Xylem development in Populus was characterized based on microscopic observations of stem sections in transgenic plants. Transcriptomic, quantitative real time PCR (qRT-PCR), chromatin immunoprecipitation (ChIP)-PCR and EMSA analyses were conducted to identify target genes involved in xylem development. Yeast two-hybrid (Y2H), pull-down, bimolecular fluorescence complementation (BiFC) and co-immunoprecipitation (IP) assays were used to validate protein-protein interactions. • PaC3H17 and its target PaMYB199 were found to be predominantly expressed in the vascular cambium and developing secondary xylem in Populus stems, and play opposite roles in controlling cambial cell proliferation and secondary cell wall (SCW) thickening through an overlapping pathway. Further, PaC3H17 interacts with PaMYB199 to form a complex, attenuating PaMYB199-driven suppression of its xylem targets. Exogenous auxin application enhances the dual control of the PaC3H17-PaMYB199 module during cambium division, thereby promoting SCW deposition. • Dual regulation of xylem formation by an auxin-mediated PaC3H17-PaMYB199 module represents a novel regulatory mechanism in Populus, increasing our understanding of the regulatory networks involved in wood formation.

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