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1.
Sci Total Environ ; 714: 136833, 2020 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-32018977

RESUMO

Hydrochemical behavior and dissolved carbon dynamics are highly-sensitive to hydrological variations in the monsoon-influenced karstic critical zone which has high chemical weathering rates and experiences strong anthropogenic impact. Continuous high-frequency monitoring in the spring outlet of a karstic catchment in Southwestern China revealed that most hydrochemical variables changed distinctively in response to hydrologic variations, influenced by mixing of different sources and miscellaneous biogeochemical processes. Na+, K+ and SO42- varied significantly with hydrology, showing weak chemostatic behavior controlled by dilution. The flushing effect and random behavior of NO3- and Cl- likely reflect agricultural inputs from high throughflow. Soil CO2 in infiltrated water supports carbonate weathering, enabling DIC (dissolved inorganic carbon) and weathering products (e.g., Ca2+ and Mg2+) to maintain chemostatic behavior. Biogenic DIC exhibited a stronger chemostatic response than carbonate sources and was the foremost control in DIC behavior. Carbon exchange between DIC and DOC (dissolved organic carbon) did not significantly influence DIC concentration and δ13C due to very low DOC concentration. More DOC was exported by flushing from increasing discharge. Hysteretic analysis indicated that the transport processes were controlled by proximal sources mixing and diverse mobilization in various periods responding to rainstorms. NO3- and Cl- presented different hysteresis behavior as sourced from agricultural activities. DOC increased on the hydrograph rising limb and was controlled by a transport-limited regime. However, the hysteresis behavior of most weathering products and DIC were regulated by a process-limited regime in the karstic critical zone. Overall, biogeochemical processes, hydrogeological properties, storm intensity/magnitude and the timing of storms (antecedent conditions) are main factors influencing the response of hydrochemical variables and dissolved carbon to storm events.

2.
Nat Commun ; 11(1): 490, 2020 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-31980657

RESUMO

The oxidized platinum (Pt) can exhibit better electrocatalytic activity than metallic Pt0 in the hydrogen evolution reaction (HER), which has aroused great interest in exploring the role of oxygen in Pt-based catalysts. Herein, we select two structurally well-defined polyoxometalates Na5[H3Pt(IV)W6O24] (PtW6O24) and Na3K5[Pt(II)2(W5O18)2] (Pt2(W5O18)2) as the platinum oxide model to investigate the HER performance. Electrocatalytic experiments show the mass activities of PtW6O24/C and Pt2(W5O18)2/C are 20.175 A mg-1 and 10.976 A mg-1 at 77 mV, respectively, which are better than that of commercial 20% Pt/C (0.398 A mg-1). The in situ synchrotron radiation experiments and DFT calculations suggest that the elongated Pt-O bond acts as the active site during the HER process, which can accelerate the coupling of proton and electron and the rapid release of H2. This work complements the knowledge boundary of Pt-based electrocatalytic HER, and suggests another way to update the state-of-the-art electrocatalyst.

3.
J Clin Neurosci ; 72: 169-173, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31911108

RESUMO

To investigate the differences in the epidemiological and clinical characteristics of patients with intracerebral hemorrhage (ICH) treated at our institution over the last few decades. Two chronological cohorts with ten-year-interval were established and epidemiological and clinical data were retrospectively collected from patients with ICH, and data were analyzed using SPSS 13.0. The time windows for the two cohorts were from January 1, 2010 to December 31, 2014 (2010-2014 cohort) and January 1, 2000 to December 31, 2004 (2000-2004 cohort). 1598 patients with ICH were enrolled: 360 patients in the 2000-2004 cohort and 1238 patients in the 2010-2014 cohort. ICH often occurred in patients aged from 45 to 75 years, without a sex bias, accounting for 69.6% of patients. Hypertension (60.7%) was still the main risk factors. Meanwhile, the risk factors of smoking (28.9%) and drinking (23.3%) were often present in male patients but not female patients (p ≤ 0.001). The incidence of pulmonary infection, the main complication during hospitalization, was 40.8% in the 2000-2004 cohort and 61.8% in the 2010-2014 cohort (p ≤ 0.001). Moreover, the incidence of gastrointestinal hemorrhage was 12.5% in the 2000-2004 cohort and 6.0% in the 2010-2014 cohort (p ≤ 0.001). The epidemiological and clinical features have changed over the past 10 years. The mortality was reduced but still high, as evidenced by the increased hospitalization rate of patients with ICH. Current preventions and therapeutic strategies for ICH are effective, but more strategies must be developed to improve the outcome of ICH and decrease the incidence of pulmonary infection.

4.
J Natl Cancer Inst ; 2020 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-31917448

RESUMO

BACKGROUND: Although 20 pancreatic cancer susceptibility loci have been identified through genome-wide association studies (GWAS) in individuals of European ancestry, much of its heritability remains unexplained and the genes responsible largely unknown. METHODS: To discover novel pancreatic cancer risk loci and possible causal genes, we performed a pancreatic cancer transcriptome-wide association study (TWAS) in Europeans using three approaches, FUSION, MetaXcan and SMulTiXcan. We integrated GWAS summary statistics from 9,040 pancreatic cancer cases and 12,496 controls, with gene expression prediction models built using transcriptome data from histologically normal pancreatic tissue samples (NCI Laboratory of Translational Genomics, LTG (n = 95) and Genotype-Tissue Expression, GTEx v7 (n = 174) datasets), and data from 48 different tissues (GTEx v7, n = 74-421 samples). RESULTS: We identified 25 genes whose genetically predicted expression was statistically significantly associated with pancreatic cancer risk (FDR < 0.05), including 14 candidate genes at 11 novel loci (1p36.12: CELA3B; 9q31.1: SMC2, SMC2-AS1; 10q23.31: RP11-80H5.9; 12q13.13: SMUG1; 14q32.33: BTBD6; 15q23: HEXA; 15q26.1: RCCD1; 17q12:, PNMT, CDK12, PGAP3; 17q22: SUPT4H1; 18q11.22: RP11-888D10.3; and 19p13.11: PGPEP1) and 11 at 6 known risk loci (5p15.33: TERT, CLPTM1L, ZDHHC11B; 7p14.1: INHBA; 9q34.2: ABO; 13q12.2: PDX1; 13q22.1: KLF5; and 16q23.1: WDR59, CFDP1, BCAR1, TMEM170A). The association for 12 of these genes (CELA3B, SMC2, and PNMT at novel risk loci, and TERT, CLPTM1L, INHBA, ABO, PDX1, KLF5, WDR59, CFDP1 and BCAR1 at known loci) remained statistically significant after Bonferroni correction. CONCLUSIONS: By integrating gene expression and genotype data, we identified novel pancreatic cancer risk loci and candidate functional genes that warrant further investigation.

5.
Sci Total Environ ; 707: 135628, 2020 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-31784157

RESUMO

The effect of dams on dissolved inorganic carbon (DIC) transport and riverine ecosystems is unclear in karst cascade reservoirs. Here, we analyzed water samples from a karst river system with seven cascade reservoirs along the Wujiang River, southwestern China, during one hydrological year. From upstream to downstream, the average concentration of DIC increased from 2.2 to 2.6 mmol/L and its carbon isotope composition (δ13CDIC) decreased from -8.0 to -10‰. Meanwhile, the air temperature (Ta) increased from 20.3 °C to 26.7 °C and 10 °C to 13.7 °C in the warm and cold seasons, respectively. The results suggest that a cascade of dams has a stronger effect on DIC dynamics and retention than a single dam. The good correlation between Ta/HRT (hydraulic retention time) and Δ[DIC] as well as Δ[δ13CDIC] mean that Ta and HRT affected the magnitude of the damming effect by altering changes in concentration of DIC and δ13CDIC in the reservoir compared to the inflowing water. In particular, daily regulated reservoirs with short retention times acted more like river corridors and had a smaller effect on carbon dynamics, so modulating retention time might be used reduce the effect of dams on the riverine ecosystem.

6.
Cytokine ; 127: 154936, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31786500

RESUMO

BACKGROUND: Immuno-inflammation plays an important role in the pathophysiological process of sepsis-associated acute hepatic injury (AHI). Interleukin 27 (IL-27) is an important inflammatory regulator; however, its role in this condition is not clear. METHODS: The clinical data and IL-27 serum levels in sepsis patients with or without AHI were analysed. Classical caecal ligation puncture (CLP) models were established in wild-type (WT) and IL-27 receptor (WSX-1)-deficient (IL-27R-/-) mice. In addition, exogenous IL-27 was injected into these mice, and the levels of IL-27, IL-6, and tumour necrosis factor alpha (TNF-α) in the serum and liver were then measured by enzyme-linked immunoassay (ELISA), quantitative PCR, and Western blotting. The severity of liver damage was evaluated by haematoxylin and eosin staining of liver tissue, TUNEL assay and evaluation of alanine aminotransferase (ALT) and aspartate transaminase (AST) serum levels. Furthermore, the effects of IL-27 on the levels of phosphorylated c-Jun N-terminal kinase (JNK) in macrophages were assessed by Western blotting, and the effects of IL-27 on the expression of IL-6 and TNF-α in macrophages were assessed by ELISA. RESULTS: IL-27 was elevated in sepsis patients with acute hepatic injury, which correlated with the Acute Physiologic Assessment and Chronic Health Evaluation II (APACHEII) scores, Sequential Organ Failure Assessment (SOFA) scores, and procalcitonin, C-reactive protein, IL-6, and TNF-α expression. In the CLP-WT group, IL-27 was highly expressed in the serum and liver, which correlated with the elevated content of ALT, AST, TNF-α, IL-6, and p-JNK in the serum and liver and the pathological injury of the liver. In CLP-IL-27R-/- group, however, the levels of ALT, AST, TNF-α, IL-6, and p-JNK in the serum and liver and the pathological injury of the liver were decreased. Treatment with exogenous IL-27 led to a further increase in these cytokines in WT mice after CLP. IL-27 treatment and lipopolysaccharide stimulation in vitro increased the expression of p-JNK, IL-6, and TNF-α in macrophages, and these changes were decreased by a JNK signalling pathway inhibitor. CONCLUSION: IL-27 is elevated in sepsis patients, especially those with acute hepatic injury. In addition, IL-27 can promote inflammatory reactions in the CLP-induced hepatic injury mice model.

7.
Asian J Surg ; 43(1): 60-68, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30782495

RESUMO

This systematic review was designed to evaluate the efficacy of tubeless percutaneous nephrolithotomy (PCNL) versus standard percutaneous nephrolithotomy (PCNL) for kidney stones. Computerized search was performed for randomized clinical trials (RCTs) from PubMed, EMBASE, CENTRAL and Cochrane Database of Systematic Reviews databases. The included studies were randomized trials investigating tubeless PCNL versus standard PCNL in patients with kidney stones. Outcomes measured included postoperative pain, postoperative analgesia, hospital stay, drop in hemoglobin, stone free, urine leakage, blood transfusion, or pyrexia per randomized patients. In all, 15 RCTs involving 947 subjects were included. With regard to postoperative pain, analgesia, hospital stay and urine leakage, it was significantly reduced in tubeless PCNL group. In respect of drop in hemoglobin, stone free, blood transfusion and pyrexia, tubeless PCNL group appeared to be equivalent with standard PCNL group. Tubeless PCNL technology is associated with shorter hospitalization time, lower incidence of postoperative pain and less analgesia requirement after nephrolithotony. Tubeless PCNL can be used as a substitute for traditional standard PCNL of the first-line treatment. Nevertheless, further research in this field is urgently needed to confirm it.

8.
Chem Soc Rev ; 49(2): 354-381, 2020 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-31859320

RESUMO

The power conversion efficiencies (PCEs) of perovskite solar cells (PSCs) are already higher than those of other thin-film photovoltaic technologies, but the high-efficiency cells are based on complicated device architectures with multiple layers of coating. A promising strategy to commercialize this emerging technology is to simplify the device structure while simultaneously maintaining high-efficiency. Charge transport layers (CTLs) are generally indispensable for achieving high-performance PSCs, but the high cost and possibility of instability hinder the mass production of efficient, stable PSCs in a cost-effective manner. The ambipolar carrier transfer characteristic of perovskite materials makes it possible to fabricate efficient PSCs even in the absence of electron and/or hole transport layers. Encouragingly, the reported PCEs of CTL-free PSCs are already over 20%. However, it is still a mystery about why and how CTL-free devices can work efficiently. Here, we summarize the recent strategies developed to improve the performance of CTL-free PSCs, aiming at strengthening the comprehensive understanding of the fundamental carrier dynamics, heterojunction merits and device physics behind these mysteriously simple yet efficient devices. This review sheds light on identifying the limiting and determining factors in achieving high-efficiency CTL-free devices, and proposes some empirical charge transport models (e.g. p-type doping of perovskites for HTL-free PSCs, n-type doping of perovskites for ETL-free PSCs, constructing efficient p-n heterojunctions and/or homojunctions at one side/interface or employing perovskite single crystal-based lateral geometry for both HTL and ETL-free PSCs, etc.) that are useful to further improve device performance. In addition, an insightful perspective for the future design and commercial development of large-scale, efficient and stable optoelectronic devices by employing carbon electrodes is provided.

9.
Huan Jing Ke Xue ; 40(12): 5202-5212, 2019 Dec 08.
Artigo em Chinês | MEDLINE | ID: mdl-31854590

RESUMO

To study the composition characteristics and source apportionment of PM2.5 in the eastern part of the North China Plain, manual samples during the two-year heating period of 2016 and 2017 were collected in seven cities, including Hengshui, Cangzhou, Ji'nan, Dezhou, Binzhou, Zibo, and Liaocheng. The results showed that the average values of ρ(PM2.5) during the observation periods were 137.23 µg·m-3 and 111.83 µg·m-3, respectively, which exceeded the daily average secondary standard limit of GB 3095-2012 "Environmental Air Quality Standard" by 1.8 and 1.5 times, respectively. The mean mass of water-soluble ions accounted for 53.32% and 47.04% of ρ(PM2.5), respectively, of which SNA (NO3-, SO42-, and NH4+) were the main ions. During the 2016 and 2017 observation periods, NO3-/SO42- increased from 1.35 to 1.60, while the concentration of Cl- decreased, indicating a decrease in the impact of coal burning. The proportions of secondary organic carbon (SOC) in organic carbon (OC) were 71.63% and 55.35%, respectively, indicating the source of secondary organic carbon had decreased. Analysis of characteristic elements Fe/Al and Ba/Ni showed that dust sources and vehicle sources had increased significantly. The backward trajectories of air mass results showed that the polluted air mass mainly came from the northwest direction during the observation period. However, the PM2.5 concentration was highest when the air mass came from the Anhui and Jiangsu provinces.

10.
Huan Jing Ke Xue ; 40(6): 2930-2938, 2019 Jun 08.
Artigo em Chinês | MEDLINE | ID: mdl-31854688

RESUMO

Increasing evidence suggests that ammonia oxidation in acidic soils is primarily catalyzed by ammonia-oxidizing archaea (AOA), while ammonia-oxidizing bacteria (AOB) drive ammonia oxidation in neutral and alkaline soils in which AOA overwhelmingly outnumber AOB. Therefore, neutral purple soil with a pH of 7.2 was selected to study the composition of the active ammoxidation microbial community with a stable isotope nucleic acid probe technique combined with cloning sequencing. Results showed that the nitrification rate was 9.68 mg·(kg·d)-1, and AOA and AOB were abundant in neutral purple soils. By using DNA-based stable isotope probing (SIP), we gathered strong evidence of archaeal ammonia oxidation by AOA and AOB. Phylogenetic analysis indicated that the Nitrosospira Cluster 3a.1 AOB was dominant in terms of quantity at 0 days, and the Nitrosospira Cluster 3a.2 only accounted for a small part. After 56 days of cultivation, the Nitrosospira Cluster 3a.2 replaced the Nitrosospira Cluster 3a.1 as the active AOB that dominated ammonia oxidation. The AOA that predominated quantitatively at day 0 was Nitrososphaera Subcluster 9, but after cultivation this became Nitrososphaera Subcluster 3.2/3.3. Thus, the community structure of AOA and AOB changed. Active autotrophic nitrification was found in this neutral purple soil. Sequencing analysis of the 13C-labeled DNA provided robust evidence that both archaea and bacteria played important roles in the nitrification and not all ammonia oxidizers in native soil were active in the nitrification. Phylogenetic analysis clearly showed that the dominant active archaea and bacteria during the incubation were affiliated with Nitrososphaera Subcluster 3.2/3.3 within the soil group 1.1b lineage and Nitrosospira Cluster 3a.2, respectively, which were different from the dominant ammonia oxidizers at the beginning of the incubation. These results suggest that the community structure of ammonia oxidizers can shift quickly upon changes in the substrate availability in soils.

11.
Front Chem ; 7: 675, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31681729

RESUMO

Traditional intravenous chemotherapy is relative to many systemic side effects, including myelosuppression, liver or kidney dysfunction, and neurotoxicity. As an alternative method, the injectable hydrogel can efficiently avoid these problems by releasing drugs topically at the tumor site. With advantages of localized drug toxicity in the tumor site, proper injectable hydrogel as the drug delivery system has become a research hotspot. Based on different types and stages of cancer, a variety of hydrogel drug delivery systems were developed, including thermosensitive, pH-sensitive, photosensitive, and dual-sensitive hydrogel. In this review, the latest developments of these hydrogels and related drug delivery systems were summarized. In summary, our increasing knowledge of injectable hydrogel for localized cancer therapy ensures us that it is a more durable and effective approach than traditional chemotherapy. Smart release system reacting to different stimuli at different time according to the micro-environment changes in the tumor site is a promising tendency for further studies.

12.
Medicine (Baltimore) ; 98(44): e17686, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31689791

RESUMO

RATIONALE: Ependymomas are neuroepithelial tumors that typically occur in the central nervous system. Ependymomas arising in the mediastinum are exceedingly rare, with only approximately 9 isolated cases reported in the literature to date. PATIENT CONCERNS: A 35-year-old woman was referred to our hospital with complaints of progressive back pain for 3 months. Physical examination revealed decreased breathing sounds and tenderness. Contrast-enhanced computed tomography showed a soft tissue mass with heterogeneous enhancement in the right posterior mediastinum. DIAGNOSES: The diagnosis of primary mediastinal ependymomas (PMEs) was confirmed by postoperative histopathologic examination. INTERVENTIONS AND OUTCOMES: The patient underwent surgical resection of the tumor and experienced local recurrence with neck metastasis 2 years postoperatively. She underwent reoperation for the recurrent tumors and received postoperative radiotherapy and adjuvant chemotherapy. Two years later, the patient is doing well, with no evidence of tumor progression or recurrence. LESSONS: Since PMEs are exceedingly rare, treatment options are limited. Surgical resection seems to be the mainstay of treatment. Further evidence-based studies are required to prove the benefit of radiotherapy and chemotherapy in the treatment of PMEs.


Assuntos
Ependimoma/diagnóstico , Neoplasias do Mediastino/diagnóstico , Adulto , Diagnóstico Diferencial , Ependimoma/diagnóstico por imagem , Ependimoma/terapia , Feminino , Humanos , Neoplasias do Mediastino/diagnóstico por imagem , Neoplasias do Mediastino/terapia , Recidiva Local de Neoplasia , Tomografia Computadorizada por Raios X
13.
J Orthop Sci ; 2019 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-31668912

RESUMO

BACKGROUND: To investigate the alterations in body movement and their compensatory characteristics under different spinal diseases through an objective and quantitative analysis of the spinal-pelvic-lower limb motor function. METHODS: A total of 120 subjects were recruited from October 2016 to April 2017. The patients were classified into 2 groups in which 65 patients with cervical spondylotic myelopathy (CSM) and 25 patients with idiopathic scoliosis (IS). The former group was evaluated with JOA score while those in the IS group underwent Lenke classification. A control group was set up with 30 healthy subjects. All the subjects were instructed to walk at a constant speed for one minute on a treadmill, and their spinal-pelvic-lower limb motions were monitored simultaneously with a DIERS Formetric 4D® grating system and a QUINTIC gait analysis system. RESULTS: The rotation angle of thoracic and lumbar vertebrae in IS group were larger than those in the control group (P < 0.05), and the knee joint angle A in the CSM group and IS group were larger than the control group (P < 0.05). In the CSM group, the knee joint angular velocity and angular acceleration were both greater than the control group (P < 0.05). And there was a negative linear correlation between the JOA score for the lower extremity of CSM patients and their knee joint angular acceleration. CONCLUSION: IS patients tend to demonstrate increased swing amplitude of the trunk. Those with CSM will also have larger knee joint angular velocity and angular acceleration.

14.
Polymers (Basel) ; 11(10)2019 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-31600886

RESUMO

Recently, metal-organic frameworks (MOFs) have garnered enormous attention from researchers owing to their superior physicochemical properties, which are of particular interest in various fields such as catalysis and the diverse areas of biomedicine. Despite their position in the utilization for various applications compared to other innovative nanocarriers such as dendrimers and mesoporous silica nanoparticles (MSNs), in terms of advantageous physicochemical attributes, as well as attractive textural properties, ease of characterization, and abundant surface chemistry for functionalization and other benefits, MOFs yet suffer from several issues such as poor degradability, which might lead to accumulation-induced biocompatibility risk. In addition, some of the MOFs suffer from a shortcoming of poor colloidal stability in the aqueous solution, hindering their applicability in diverse biomedical fields. To address these limitations, several advancements have been made to fabricate polymeric nanocomposites of MOFs for their utility in various biomedical fields. In this review, we aim to provide a brief emphasis on various organic polymers used for coating over MOFs to improve their physicochemical attributes considering a series of recently reported intriguing studies. Finally, we summarize with perspectives.

15.
Front Cell Neurosci ; 13: 429, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31607868

RESUMO

Ischemic stroke is one of the most leading diseases causing death/long-term disability worldwide. Activating endogenous neural stem/progenitors cells (NSPCs), lining in the subventricular zone (SVZ) and dentate gyrus, facilitates injured brain tissue recovery in both short and long-term experimental settings. While, only a few proliferated NSPCs migrate toward the lesions to enhance endogenous repair after ischemia. Here, the results indicated that the functional recovery was evidently improved and the infarct volume was significantly reduced with ascorbic acid (AA) treatment in a dose-dependent manner from 125 to 500 mg/Kg, and the suitable therapeutic concentration was 250 mg/Kg. The possible mechanism might be due to activating sodium-vitamin C cotransporter 2 (SVCT2), which was down-regulated in SVZ after ischemia. Furthermore, immunostaining images depicted the number of migrated NSPCs from SVZ were significantly increased with 250 mg/Kg AA treatment or SVCT2 overexpression under the physiological and pathological condition in vivo. Besides, the data also represented that 250 mg/Kg AA or SVCT2 overexpression facilitated NSPCs migration via promoting F-actin assembling in the manner of up-regulating CDC42 expression using oxygen-glucose deprivation in vitro. Collectively, the present study indicates that SVCT2 promotes NSPCs migration through CDC42 activation to facilitate F-actin assembling, which enlarges the therapeutic scope of AA and the role of SVCT2 in NSPCs migration after brain injury.

16.
Nano Lett ; 19(11): 7827-7835, 2019 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-31577446

RESUMO

Low utilization of active metallic sodium (Na) and uncontrollable growth of Na dendrites remain significant challenges for high-performance Na metal batteries, which are limited to inefficient Na utilization (<1%) and shallow cycling conditions (0.25-1.0 mAh cm-2). In this work, a kind of Na metal anode with record-high utilization and long-term cycling stability is reported, using carbon-substrate-supported nitrogen-anchored zinc (Zn) single atoms as a current collector. Single Zn atom sites which serve as a strong "magnet" for Na ions, can guide the metallic Na uniform nucleation and free from dendrite-induced short circuit. The nucleation overpotential of our strategy is essentially zero, where most of the reported modified substrates were greatly exceed 20 mV. Specifically, the Na anodes exhibit a high Na stripping/plating Coulombic efficiency with 99.8% over 350 cycles and a stable voltage response with small voltage hysteresis after cycling 1000 h. The full cell exhibits high Na utilization up to 100% and superior long-term cycling stability for more than 1000 cycles with excellent capacity retention. In terms of lifetime and Na utilization, the Na metal anodes based on our strategy significantly outperforms the reported state-of-the-art Na metal anodes. Moreover, this affords new insights into the controllable Na nucleation behavior and high Na utilization and sheds fresh light on atomic level design of an electrode for Na metal anodes.

17.
Plant Biotechnol J ; 2019 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-31529568

RESUMO

Argonaute (AGO) proteins and small RNAs (sRNAs) are core components of the RNA-induced silencing complex (RISC). It has been reported that miRNAs regulate plant height and grain size in rice, but which AGO is involved in grain size regulation remains unclear. Here, we report that enhanced expression of OsAGO17, a putative AGO protein, could improve grain size and weight and promote stem development in rice. Cytological evidence showed that these effects are mainly caused by alteration of cell elongation. Expression analyses showed that OsAGO17 was highly expressed in young panicles and nodes, which was consistent with the expression pattern of OsmiR397b. SRNA sequencing, stem-loop RT-PCR and sRNA blotting showed that the expression of OsmiR397b was reduced in ago17 and enhanced in the OsAGO17 OE lines. Four OsmiR397b target laccase (LAC) genes showed complementary expression patterns with OsAGO17 and OsmiR397b. Combined with the results of immunoprecipitation (IP) analysis, we suggested that OsAGO17 formed an RISC with OsmiR397b and affected rice development by suppression of LAC expression. In conclusion, OsAGO17 might be a critical protein in the sRNA pathway and positively regulates grain size and weight in rice.

18.
Int J Biol Macromol ; 141: 345-350, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31491517

RESUMO

Natural resistance associated macrophage protein genes (Nramp) is one of the important candidate genes responsible for regulating immune response against pathogen infection. The aim of the present was to quantify expression of Nramp gene in response to pathogen infection. Here, a Nramp was identified and molecularly characterized from Pelteobagrus fulvidraco (PfNramp). The obtained 3134 bp cDNA fragment of PfNramp comprised a 5'-untranslated region (UTR) of 81 bp, a 3'-UTR of 1403 bp and an open reading frame (ORF) of 1650 bp, encoding a polypeptide of 549 amino acids that contained a typical structural features of Nramp domain (Pfam01566). BLAST analysis exhibited that PfNramp shared sequence similarity to other organisms, in particular to Ictalurus furcatus (92%), Danio rerio (82%), and Homo sapiens (77%). Phylogenetic analysis revealed that PfNramp is close to Teleostei. Real-time quantitative reverse transcription-PCR (qRT-PCR) analysis showed that PfNramp was expressed in all examined tissues, with the highest abundance in liver. The mRNA expression of PfNramp was remarkably increased at different time points after lipopolysaccharide (LPS), and polyriboinosinic polyribocytidylic acid (poly I:C) challenge. These results suggest that PfNramp is an inducible protein in the innate immune reactions of P. fulvidraco and probably in other fish species.

19.
Cancer Discov ; 9(10): 1372-1387, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31416802

RESUMO

Small-cell lung cancer (SCLC) is an aggressive malignancy in which inhibitors of PARP have modest single-agent activity. We performed a phase I/II trial of combination olaparib tablets and temozolomide (OT) in patients with previously treated SCLC. We established a recommended phase II dose of olaparib 200 mg orally twice daily with temozolomide 75 mg/m2 daily, both on days 1 to 7 of a 21-day cycle, and expanded to a total of 50 patients. The confirmed overall response rate was 41.7% (20/48 evaluable); median progression-free survival was 4.2 months [95% confidence interval (CI), 2.8-5.7]; and median overall survival was 8.5 months (95% CI, 5.1-11.3). Patient-derived xenografts (PDX) from trial patients recapitulated clinical OT responses, enabling a 32-PDX coclinical trial. This revealed a correlation between low basal expression of inflammatory-response genes and cross-resistance to both OT and standard first-line chemotherapy (etoposide/platinum). These results demonstrate a promising new therapeutic strategy in SCLC and uncover a molecular signature of those tumors most likely to respond. SIGNIFICANCE: We demonstrate substantial clinical activity of combination olaparib/temozolomide in relapsed SCLC, revealing a promising new therapeutic strategy for this highly recalcitrant malignancy. Through an integrated coclinical trial in PDXs, we then identify a molecular signature predictive of response to OT, and describe the common molecular features of cross-resistant SCLC.See related commentary by Pacheco and Byers, p. 1340.This article is highlighted in the In This Issue feature, p. 1325.

20.
J Nat Prod ; 82(9): 2509-2516, 2019 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-31436991

RESUMO

Eleven new pyrimidine nucleosides (1-11) and 12 known analogues (12-23) were isolated from the marine-derived Streptomyces sp. SSA28. All of the new structures were elucidated by extensive NMR spectroscopic analysis and HRESIMS data. The absolute configurations of compound 1 were determined by X-ray diffraction. The configurations of 2-16 were investigated by ECD calculations. Compounds 11-16 showed cytotoxicity against HCT-116 human colon cancer cell lines with IC50 values from 0.39 ± 0.03 to 6.63 ± 0.47 µM.

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