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1.
Metab Brain Dis ; 2020 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-32215835

RESUMO

Inflammatory demyelination in the central nervous system (CNS) is a hallmark of multiple sclerosis (MS) and its animal model, experimental autoimmune encephalomyelitis (EAE). Besides MS disease-modifying therapy, targeting myelin sheath protection/regeneration is currently a hot spot in the treatment of MS. Here, we attempt to explore the therapeutic potential of Bilobalide (BB) for the myelin protection/regeneration in EAE model. The results showed that BB treatment effectively prevented worsening and demyelination of EAE, accompanied by the inhibition of neuroinflammation that should be closely related to T cell tolerance and M2 macrophages/microglia polarization. BB treatment substantially inhibited the infiltration of T cells and macrophages, thereby alleviating the enlargement of neuroinflammation and the apoptosis of oligodendrocytes in CNS. The accurate mechanism of BB action and the feasibility of clinical application in the prevention and treatment of demyelination remain to be further explored.

2.
Nanoscale ; 2020 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-32100817

RESUMO

It is of great importance to design and develop complex heterostructured nanocatalysts with superior electrochemical performance to that of single structured ones. Here, we report the hydrothermal fabrication of a hierarchical heterostructured CuO@ZnCo layered double hydroxide nanowire array on a copper foil (CuO@ZnCo LDH/CF). As a self-supported electrocatalyst for water oxidation, CuO@ZnCo LDH/CF has superior catalytic activity with the requirement of a low overpotential of 270 mV to attain 10 mA cm-2 in 1.0 M KOH. In addition, it shows strong durability to maintain its activity for at least 24 h.

3.
Acta Pharmacol Sin ; 2020 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-31937929

RESUMO

Oroxindin is a flavonoid isolated from the traditional Chinese medicine Huang-Qin, which has shown various pharmacological activities including anti-inflammatory, antitumor, antioxidant, etc. Thus far, the effect of oroxindin on colonic inflammation and the underlying mechanism remain unknown. In this study, we investigated the tissue distribution of oroxindin and its therapeutic effects on ulcerative colitis (UC) as well as the underlying mechanisms. UC model was established in mice by administrating dextran sulfate sodium (DSS) in drinking water for 7 d. We first showed that oroxindin was largely absorbed by the colon as an active ingredient after normal mice received Huang-Qin-Tang, a traditional Chinese medicine decoction. UC mice were then treated with oroxindin (12.5, 25, 50 mg ·kg-1 ·d-1, i.g.) for 10 d. We found that oroxindin treatment greatly suppressed massive macrophages infiltration and attenuated pathological changes in colonic tissue. Furthermore, oroxindin treatment significantly inhibited the generation of IL-1ß and IL-18 in the colon via inhibiting the nucleotide-binding oligomerization domain-like receptor 3 (NLRP3) inflammasome formation and activation. In cultured macrophages, LPS induced NLRP3 inflammasome formation and caspase-1 activation, which were suppressed by oroxindin (12.5-50 µM). In LPS-treated macrophages, oroxindin dose-dependently restored the expression of TXNIP protein, leading to suppressing TXNIP-dependent NF-κB activation. In conclusion, these results demonstrate that oroxindin could be absorbed by the colon and attenuate inflammatory responses via inhibiting NLRP3 inflammasome formation and activation, which is related to the inhibitory effect on TXNIP-dependent NF-κB-signaling pathway. Hence, oroxindin has the potential of becoming an effective drug for treating UC.

4.
Biochim Biophys Acta Mol Cell Biol Lipids ; 1865(4): 158609, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31917335

RESUMO

STARD4, a member of the evolutionarily conserved START gene family, is a soluble sterol transport protein implicated in cholesterol sensing and maintenance of cellular homeostasis. STARD4 is widely expressed and has been shown to transfer sterol between liposomes as well as organelles in cells. However, STARD4 knockout mice lack an obvious phenotype, so the overall role of STARD4 is unclear. To model long term depletion of STARD4 in cells, we use short hairpin RNA technology to stably decrease STARD4 expression in human U2OS osteosarcoma cells (STARD4-KD). We show that STARD4-KD cells display increased total cholesterol, slower cholesterol trafficking between the plasma membrane and the endocytic recycling compartment, and increased plasma membrane fluidity. These effects can all be rescued by transient expression of a short hairpin RNA-resistant STARD4 construct. Some of the cholesterol increase was due to excess storage in late endosomes or lysosomes. To understand the effects of reduced STARD4, we carried out transcriptional and lipidomic profiling of control and STARD4-KD cells. Reduction of STARD4 activates compensatory mechanisms that alter membrane composition and lipid homeostasis. Based on these observations, we propose that STARD4 functions as a critical sterol transport protein involved in sterol sensing and maintaining lipid homeostasis.

5.
J Cell Mol Med ; 24(1): 772-784, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31736268

RESUMO

SPRY4-intronic transcript 1 has been found in several kinds of cancers, but the role of SPRY4-IT1 in breast cancer stem cells has not been studied. We investigated whether SPRY4-IT1 is involved in the promotion of breast cancer stem cells (BCSCs). We used qRT-PCR to detect the expression of SPRY4-IT1 in MCF-7 cells and MCF-7 cancer stem cells (MCF-7 CSCs). The effects of SPRY4-IT1 on the proliferation and renewal ability of breast cancer cells were investigated by in vitro and in vivo assays (ie in situ hybridization, colony formation assay, sphere formation assay, flow cytometry assay, western blotting, xenograft model and immunohistochemistry). The mechanism of SPPRY4-IT1 as a ceRNA was studied by a dual-luciferase reporter assay and bioinformatic analysis. In our study, SPRY4-IT1 was up-regulated in MCF-7 CSCs compared with MCF-7 cells, and high SPRY4-IT1 expression was related to reduced breast cancer patient survival. Furthermore, SPRY4-IT1 overexpression promoted breast cancer cell proliferation and stemness in vitro and in vivo. In addition, SPRY4-IT1 knockdown suppressed BCSC renewal ability and stemness maintenance in vivo and in vitro. The dual-luciferase reporter assays indicated that SPRY4-IT1 as a sponge for miR-6882-3p repressed transcription factor 7-like 2 (TCF7L2) expression. Taken together, these findings demonstrated that SPRY4-IT1 promotes proliferation and stemness of breast cancer cells as well as renewal ability and stemness maintenance of BCSCs by increasing the expression of TCF7L2 through targeting miR-6882-3p.

6.
Neuron ; 105(3): 522-533.e4, 2020 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-31806492

RESUMO

The timing and size of inhibition are crucial for dynamic excitation-inhibition balance and information processing in the neocortex. The underlying mechanism for temporal control of inhibition remains unclear. We performed dual whole-cell recordings from pyramidal cells (PCs) and nearby inhibitory interneurons in layer 5 of rodent neocortical slices. We found asynchronous release (AR) of glutamate occurs at PC output synapses onto Martinotti cells (MCs), causing desynchronized and prolonged firing in MCs and thus imprecise and long-lasting inhibition in neighboring PCs. AR is much stronger at PC-MC synapses as compared with those onto fast-spiking cells and other PCs, and it is also dependent on PC subtypes, with crossed-corticostriatal PCs producing the strongest AR. Moreover, knocking out synaptotagmin-7 substantially reduces AR strength and recurrent inhibition. Our results highlight the effect of glutamate AR on the operation of microcircuits mediating slow recurrent inhibition, an important mechanism for controlling the timing and size of cortical inhibition.

7.
Sci Total Environ ; 706: 135711, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31791784

RESUMO

The environmental toxicity of silver nanoparticles (AgNPs) is currently the focus of intensive research. However, the mechanisms underlying the cytotoxic effects of AgNPs on denitrifying microbes have yet to be explicitly demonstrated. Herein, Pseudomonas stutzeri was used to explore the effects of AgNPs on denitrification and cytotoxicity. The denitrification efficiency decreased from 94.91% in the AgNP-free treatment to 87.66%, 60.51% and 36.10% with treatments of 3.125, 6.25 and 12.5 mg/L AgNPs, respectively. The inhibition and delay in the denitrification process from treatment with AgNPs likely occurred through alteration of the viability and metabolic activity of P. stutzeri. Flow cytometry analysis indicated that the early apoptotic rates of P. stutzeri were 8.72%, 30.60%, and 48.60% with treatments of 3.125, 6.25, and 12.5 mg/L AgNPs, respectively. Results for scanning electron microscope (SEM) imaging, ζ-potential analysis, lactate dehydrogenase (LDH) release and malondialdehyde (MDA) production assays demonstrated adsorption of AgNPs on the cell surface, which altered membrane potential and mediated lipid peroxidation; these events eventually resulted in the aberration of cell morphology. Transmission electron microscopy (TEM) images and measurements of Ag content distribution by ICP-MS indicated that AgNPs were easily internalized by P. stutzeri, which increased the accumulation of reactive oxygen species (ROS). Furthermore, the presence of AgNPs also greatly inhibited expression of genes napA, nirS, cnorB, and nosZ, thereby reducing the activities of nitrate reductase (NAR) and nitrite reductase (NIR). These findings will help further our understanding of the mechanism underlying AgNPs cytotoxicity, and provide the means to evaluate the negative effect of nanoparticles in the environment.

8.
Drug Deliv ; 27(1): 81-90, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31858857

RESUMO

There are many kinds of biological activities of resveratrol itself, but its clinical application is limited by its poor solubility in water and low bioavailability. Therefore, we have prepared glycyrrhizic acid-conjugated human serum albumin nanoparticles wrapping resveratrol nanoparticles (GL-HSA-RESNPs). The purpose of this study was to investigate the bioavailability, pharmacokinetics and tissue distribution of resveratrol in rats after single-dose tail vein injection administration of GL-HSA-RESNPs. A sensitive and reliable high performance liquid chromatography (HPLC) method was established to verify the content of resveratrol in rat plasma and organs. The Cmax value after GL-HSA-RESNPs administration was significantly higher than that of resveratrol suspension (933 ± 76.64 ng/mL vs. 618 ± 42.54 ng/mL, p < .01). The Tmax value obtained after GL-HSA-RESNPs administration was significantly shorter than that after resveratrol suspension administration (0.17 ± 0.01 h vs. 0.25 ± 0.01 h, p < .001). The bioavailability of GL-HSA-RESNPs was 4.25 times higher than that of the pure resveratrol. The concentration of resveratrol in the main organs of rats treated with the GL-HSA-RESNPs was higher than that in rats treated with the pure resveratrol. Rats treated with GL-HSA-RESNPs had the highest concentration of resveratrol in their liver. It is indicated that GL-HSA-RESNPs is a promising liver-targeted delivery system that improves the in vivo bioavailability of resveratrol.

9.
Front Genet ; 10: 1183, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31798641

RESUMO

In the genetic improvement of livestock and poultry, residual feed intake (RFI) is an important economic trait. However, in sheep, the genetic regulatory mechanisms of RFI are unclear. In the present study, we measured the feed efficiency (FE)-related phenotypes of 137 male Hu lambs, and selected six lambs with very high (n = 3) and very low (n = 3) RFI values and analyzed their liver transcriptomes. A total of 101 differentially expressed genes were identified, of which 40 were upregulated and 61 were downregulated in the low-RFI group compared with that in the high-RFI group. The downregulated genes were mainly concentrated in immune function pathways, while the upregulated genes were mainly involved in energy metabolism pathways. Two differentially expressed genes, ADRA2A (encoding adrenoceptor alpha 2A) and RYR2 (ryanodine receptor 2), were selected as candidate genes for FE and subjected to single nucleotide polymorphism scanning and association analysis. Two synonymous mutations, ADRA2A g.1429 C > A and RYR2 g.1117 A > C, were detected, which were both significantly associated with the feed conversion rate. These findings provide a deeper understanding of the molecular mechanisms regulating FE, and reveal key genes and genetic variants that could be used to genetically improve FE in sheep.

10.
BMJ Open Diabetes Res Care ; 7(1): e000735, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31798896

RESUMO

Objective: To derive, and externally validate, a risk score for cardiovascular death among patients with type 2 diabetes and newly diagnosed diabetic nephropathy (DN). Research design and methods: Two independent prospective cohorts with type 2 diabetes were used to develop and externally validate the risk score. The derivation cohort comprised 2282 patients with an incident, clinical diagnosis of DN. The validation cohort includes 950 patients with incident, biopsy-proven diagnosis of DN. The outcome was cardiovascular death within 2 years of the diagnosis of DN. Logistic regression was applied to derive the risk score for cardiovascular death from the derivation cohort, which was externally validated in the validation cohort. The score was also estimated by applying the United Kingdom Prospective Diabetes Study (UKPDS) risk score in the external validation cohort. Results: The 2-year cardiovascular mortality was 12.05% and 11.79% in the derivation cohort and validation cohort, respectively. Traditional predictors including age, gender, body mass index, blood pressures, glucose, lipid profiles alongside novel laboratory test items covering five test panels (liver function, serum electrolytes, thyroid function, blood coagulation and blood count) were included in the final model.C-statistics was 0.736 (95% CI 0.731 to 0.740) and 0.747 (95% CI 0.737 to 0.756) in the derivation cohort and validation cohort, respectively. The calibration slope was 0.993 (95% CI 0.974 to 1.013) and 1.000 (95% CI 0.981 to 1.020) in the derivation cohort and validation cohort, respectively.The UKPDS risk score substantially underestimated cardiovascular mortality. Conclusions: A new risk score based on routine clinical measurements that quantified individual risk of cardiovascular death was developed and externally validated. Compared with the UKPDS risk score, which underestimated the cardiovascular disease risk, the new score is a more specific tool for patients with type 2 diabetes and DN. The score could work as a tool to identify individuals at the highest risk of cardiovascular death among those with DN.

11.
Medicine (Baltimore) ; 98(50): e18411, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31852163

RESUMO

RATIONALE: Primary sclerosing cholangitis (PSC) is recognized as an autoimmune-mediated liver disease characterized by progressive biliary inflammation and fibrosis. Some PSC cases with elevated immunoglobulin G4 (IgG4) levels are likely to be misdiagnosed with immunoglobulin G4-related sclerosing cholangitis (IgG4-SC). Thus, distinguishing these 2 diseases is particularly important. PATIENT CONCERNS: A 34-year-old male presented with right hypochondrium abdominal intermittent pain and jaundice lasting for 1 month. Here, we present a case of PSC with increased IgG4 levels with improvement of quality of life upon liver transplantation (LT). DIAGNOSIS: The diagnosis of PSC was confirmed based on clinical symptoms, laboratory test results, imaging findings, pathologic results and a lack of response to steroid therapy. INTERVENTIONS: LT surgery was performed successfully when his vital parameters were stabilized. Immunosuppressive agents were routinely used after LT. OUTCOMES: Three years after LT, liver function values show that alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were in the normal range. An abdominal ultrasonography showed no obvious abnormalities. LESSONS: There are similar biochemical characteristics and cholangiographic findings between PSC and IgG4-SC. Therefore, distinguishing these 2 diseases is particularly important. LT remains the only option for end-stage PSC. Early diagnosis and effective treatment can achieve a good prognosis.


Assuntos
Colangite Esclerosante/diagnóstico , Imunoglobulina G/sangue , Dor Abdominal/etiologia , Adulto , Colangite Esclerosante/cirurgia , Humanos , Icterícia/etiologia , Transplante de Fígado , Masculino
12.
Microorganisms ; 7(11)2019 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-31726755

RESUMO

Enterobacteriaceae having chromosomally-encoded mcr-1 is rarely reported. In this study, we recovered a chromosomal mcr-1 carrying Escherichia coli, designated HeN100, from the feces of a diarrheal pig in China. Antimicrobial susceptibility testing showed that HeN100 was resistant to three aminoglycosides, twelve ß-lactams including three carbapenems, one phenicol, two tetracyclines, two fluoroquinolones, nitrofurantoin, and colistin tested. Oxford Nanopore MinION sequencing revealed that the complete genomes of the multidrug resistant (MDR) HeN100 consisted of a single circular chromosome and five circular plasmids. Bioinformatical analysis determined HeN100 as ST695 and it contained many acquired resistance genes responsible for its MDR phenotypes, including colistin resistance mcr-1 and the carbapenem resistance blaNDM-1, and most of these genes were located on plasmids. However, the mcr-1 was found on the chromosome, and it was located between an IS30-like element ISApl1 and a PAP2-like encoding gene. These three genes consisted of an "ISApl1-mcr-1-orf" segment and inserted in high AT-rich regions. Finally, we found the blaNDM-1 was carried on an IncFII type conjugative plasmid. The conjugation frequency of this plasmid was 7.61 ± 2.11 × 10-5 per recipient, and its conjugation conferred resistance to carbapenems and other ß-lactams, as well as aminoglycosides. The spread of this mcr-1/blaNDM-1-carrying E. coli ST695 represents a great concern of public health.

13.
Gen Physiol Biophys ; 38(5): 407-416, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31595882

RESUMO

The P2X7 receptor (P2X7R) plays an important role in inflammatory and neuropathic pain. Our recent study indicated that activation of P2X7R in microglial cells of spinal cord contributes to the inflammatory pain induced by BmK I, the major active compound from Buthus martensi Karsch (BmK). In the present study, we further investigated whether P2X7R in satellite glial cells (SGCs) of dorsal root ganglion (DRG) is involved in the BmK I-induced pain in rats. The results found that the expression of P2X7R in SGCs was increased in the ipsilateral side of L4-L5 DRGs after intraplantar injection of BmK I. Moreover, the expression of an inflammatory cytokine IL-1ß was increased in DRG after BmK I injection. Systemic administration of an inhibitor of P2X7R (A-438079) significantly inhibited both spontaneous and evoked nociceptive behaviors induced by BmK I. These results suggest that the P2X7R in SGCs of DRG might contribute to pain induced by toxins that sensitize peripheral sensory nerves.


Assuntos
Gânglios Espinais/patologia , Dor/induzido quimicamente , Dor/patologia , Receptores Purinérgicos P2X7/metabolismo , Células Satélites Perineuronais/metabolismo , Venenos de Escorpião , Animais , Dor/metabolismo , Ratos
14.
Genes (Basel) ; 10(8)2019 08 14.
Artigo em Inglês | MEDLINE | ID: mdl-31416156

RESUMO

The SPP1, LAP3, and LCORL are located on chromosome 6 of sheep and a domain of 36.15-38.56 Mb, which plays an essential role in tissue and embryonic growth. In this study, we cloned the complete coding sequences of SPP1 and partial coding regions of LAP3 and LCORL from Hu sheep (Gansu Province, China) and analyzed their genomic structures. The RT-qPCR showed that the three genes were expressed widely in the different tissues of Hu sheep. The SPP1 expression was significantly higher in the kidney (p < 0.01) and LAP3 expression was significantly higher in the spleen, lung, kidney, and duodenum than in the other tissues (heart, liver, rumen, muscle, fat, and ovary; p < 0.05). The LCORL was preferentially expressed in the spleen, duodenum, and lung (p < 0.05). In addition, the nucleotide substitution NM_001009224.1:c.132A>C was found in SPP1; an association analysis showed that it was associated with birth weight and yearling weight (p < 0.05), and NM_001009224.1:c.132C was the dominant allele. Two mutations XM_012179698.3:c.232C>G and XM_012179698.3:c.1154C>T were identified in LAP3. The nucleotide substitution XM_012179698.3:c.232C>G was confirmed to be associated with birth weight, 1-month weight, 3-month weight (p < 0.05), and 2-month weight (p < 0.01). The nucleotide substitution XM_012179698.3:c.1154C>T was associated with birth weight (p < 0.01), 1-month weight, and 2-month weight (p < 0.05). The LAP3 gene XM_012179698.3:c.232C>G mutation with the C allele has higher body weight than other sheep, and CC genotype individuals show higher birth weight, 1-month weight, and weaning weight than the GG genotype individuals (p < 0.05). Our results support the conclusion that the mutations on ovine SPP1 and LAP3 successfully track functional alleles that affect growth in sheep, and these genes could be used as candidate genes for improving the growth traits of sheep during breeding.


Assuntos
Peso Corporal/genética , Leucil Aminopeptidase/genética , Osteopontina/genética , Característica Quantitativa Herdável , Proteínas Repressoras/genética , Ovinos/genética , Animais , Leucil Aminopeptidase/metabolismo , Osteopontina/metabolismo , Locos de Características Quantitativas , Proteínas Repressoras/metabolismo , Ovinos/crescimento & desenvolvimento
15.
Medicine (Baltimore) ; 98(27): e16340, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31277187

RESUMO

Cardiovascular disease (CVD) is the leading cause of death in patients with end-stage renal disease (ESRD) treated by dialysis. Pulse pressure (PP) as an independent prognostic factor of cardiovascular risk might be clinically implicated in predicting the short-term deaths due to cardiovascular diseases in ESRD patients. This study aimed to investigate the dose-response association between PP and risk of cardiovascular mortality in patients initializing peritoneal dialysis (PD). All patients registered with the Henan Peritoneal Dialysis Registry (HPDR) between 2007 and 2014 were incorporated in the current cohort study. PP was assessed by the date of initialisation of PD and cardiovascular mortality in 2 years after the initialisation of PD was defined as the outcome. All accessible clinical measurements were screened as covariables. Further dose-response relationships between PP and risks were explored using spline models. There was a non-linear relationship between PP and the risk of 2-year death for a cardiovascular diseases (P <.001 for linearity test). The PP associated with the lowest risk of cardiovascular mortality was 61 (95% CI 56-64) mmHg. In ESRD patients initializing PD, PP is a good prognostic factor of risk of short-term cardiovascular mortality. The risk is lowest with a PP of 56 to 64 mmHg.


Assuntos
Pressão Sanguínea , Doenças Cardiovasculares/mortalidade , Falência Renal Crônica/fisiopatologia , Adulto , Doenças Cardiovasculares/etiologia , Feminino , Humanos , Incidência , Falência Renal Crônica/mortalidade , Falência Renal Crônica/terapia , Masculino , Pessoa de Meia-Idade , Diálise Peritoneal , Valor Preditivo dos Testes , Estudos Prospectivos
16.
Int J Biol Macromol ; 138: 207-214, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31306708

RESUMO

In this work, paclitaxel was loaded into porous starch in the form of nanoparticles (PNPS), and the properties of PNPS were investigated by using raw paclitaxel and the system of paclitaxel directly loaded into porous starch (PPS) as control groups. According to the tested results, the drug loading (DL) and encapsulation efficiency (EE) of PNPS were 14.13%±0.27% and 73.92%±0.54%, higher than that of PPS (9.79%±0.31% and 71.17%±0.67%) respectively. Compared with raw paclitaxel and PPS, PNPS exhibited the more prominent dissolution rate and bioavailability, in which the bioavailability of PPS and PNPS were 2.94 and 5.42 times of that of raw paclitaxel respectively. In addition, the IC50 values of raw paclitaxel, PPS and PNPS on Lewis Lung Carcinoma (LLC) cells were 17,703.41±15.76µM, 95.10±5.32µM and 85.68±7.38µM respectively. Furthermore, the residues of acetone in PPS and PNPS were less than the ICH limit for acetone in class III solvents. To summarize, the preparation of PNPS was a potential method to improve the dissolution and bioavailability of paclitaxel.


Assuntos
Portadores de Fármacos/química , Nanopartículas/química , Paclitaxel/química , Paclitaxel/farmacocinética , Amido/química , Disponibilidade Biológica , Linhagem Celular Tumoral , Humanos , Paclitaxel/farmacologia , Tamanho da Partícula , Porosidade , Solubilidade , Solventes/química
17.
Nanoscale ; 11(41): 19274-19277, 2019 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-31215588

RESUMO

The Haber-Bosch process for industrial-scale NH3 production suffers from harsh conditions and serious CO2 release. Electrochemical N2 reduction is an alternative approach to synthesize NH3 under ambient conditions, but it requires highly-efficient electrocatalysts for the N2 reduction reaction (NRR). In this Communication, we demonstrate that WO3 nanosheets rich in oxygen vacancies (R-WO3 NSs) exhibit greatly enhanced NRR performances. In 0.1 M HCl, such R-WO3 NSs achieve a large NH3 yield of 17.28 µg h-1 mgcat.-1 and a high faradaic efficiency of 7.0% at -0.3 V vs. a reversible hydrogen electrode, much superior to the WO3 nanosheets deficient in oxygen vacancies (6.47 µg h-1 mgcat.-1 and 1.02%). Remarkably, R-WO3 NSs also show high electrochemical stability.

18.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 37(3): 290-294, 2019 Jun 01.
Artigo em Chinês | MEDLINE | ID: mdl-31218864

RESUMO

OBJECTIVE: To analyze the risk factors of preoperative upper respiratory infections in children with cleft lips and palate (CLP) and investigate preventive measures to reduce infections and improve the quality of treatments. METHODS: A total of 510 children with CLP of ages 3 years old or younger were selected from hospital cases from June to December 2017. The test group comprised 50 children with upper respiratory infections, whereas the control group comprised 460 children without upper respiratory infections. A t-test and a multivariate logistic analysis were utilized to analyze the risk factors and to investigate the preventive measures. RESULTS: Feeding patterns, the presence of infected companions during hospitalization, and ventilation at night were statistically significant. The feeding patterns and the presence of infected companions during hospitalization were independent risk factors for upper respiratory infections in children with CLP. CONCLUSIONS: Bottle feeding, infected companions during hospitalization, and the absence of window ventilation at night are risk factors for preoperative upper respiratory infections in children 3 years old or younger with CLP. Among the risk factors identified, feeding patterns and the presence of infected companion during hospitalization were the most influential. Medical staff members should streng-then corresponding health education and nursing measures to control the risk factors.


Assuntos
Fenda Labial , Fissura Palatina , Infecção Hospitalar , Criança , Pré-Escolar , Fenda Labial/cirurgia , Fissura Palatina/cirurgia , Infecção Hospitalar/prevenção & controle , Humanos , Fatores de Risco
19.
Talanta ; 202: 323-328, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31171189

RESUMO

In this study, we have designed and synthesized a novel 'AND' logic based fluorescence probe,1-(3',6'-bis((tert-butyldiphenylsilyl)oxy)-3-oxospiro (isoindoline-1,9'-xanthen)-2-yl)-3-phenylthiourea (FPSi), for the rapid (3 min) simultaneous detection of F- and Hg2+ in DMSO/H2O solution (7:3, v/v). The FPSi probe, synthesized over three steps starting from commercially available fluorescein, was constructed by attaching tert-butyldiphenylsilyl and thiosemicarbazide (as the specific identification groups for F- and Hg2+) to the skeleton of fluorescein, respectively. FPSi produced no fluorescence response towards the addition of F- or Hg2+ separately. However, when the probe was exposed to a solution containing both F- and Hg2+, there was a significant yellow-green fluorescence. FPSi demonstrated an excellent selectivity towards both F- and Hg2+ in the presence of interfering substances. The results of TOF-MS-EI analysis indicated that the response of FPSi towards F- and Hg2+ was mainly aroused by the F- promoted cleavage of Si-O bond, and Hg2+ triggered an irreversible desulfurization reaction leading to the spiral ring opening. Furthermore, the FPSi probe has been successfully used to detect F- and Hg2+ ions in tap water and cropland soil.

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