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2.
J Inorg Biochem ; 206: 111022, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32070916

RESUMO

Six novel organotin phosphonate complexes, [(Me3Sn)4(HL1)4]n1, [(Me3Sn)2(HL2)2]n2, [(Me3Sn)2L3(H2O)]n3, [(Ph3Sn)(HL1)]64, [(Ph3Sn)2L2]n5 and [(Ph3Sn)2L3]66, derived from phosphonic acid ligands [NaHL1 = 1-C10H7OPO2(OH)Na, H2L2 = 1-C10H7PO(OH)2, H2L3 = 2-C10H7PO(OH)2], have been synthesized and characterized by elemental analysis, FT-IR, NMR (1H, 13C, 31P and 119Sn) spectroscopy and X-ray crystallography. The structural analysis reveals that complexes 1 and 5 display 1D infinite zig-zag chain structures, and complex 2 shows 1D right-handed helical chain structure, while complex 3 displays 1D left-handed helical chain structure. Complexes 4 and 6 are 24-membered macrocyclic rings interconnected by P, O and Sn atoms. Additionally, the molecules of complexes 1 and 3 are further linked through intermolecular π···π and O-H···O interaction into supramolecular structures, respectively. Furthermore, we preliminarily estimated in vitro cytostatic activity of complexes 1-6 against the human cervix tumor cells (HeLa), human hepatocellular carcinoma cells (HepG-2) and human normal breast cells (HBL-100). Importantly, the anti-proliferative properties and possible pathway of complex 6 are investigated, and the results demonstrate that complex 6 could induce apoptotic cell death via an overload of intracellular reactive oxygen species (ROS) levels and the dysfunctional depolarization of mitochondrial membranes.

3.
Artigo em Inglês | MEDLINE | ID: mdl-31831430

RESUMO

A highly sensitive and selective optical fiber-based enzymatic biosensor has been proposed in the present study for detection of uric acid (UA) in human serum. The working mechanism of sensor depends on surface plasma property and localized surface plasmon resonance technique. For this purpose, a micro-ball fiber sensor probe of 350 µm diameter was fabricated using advanced fusion-splicer and coated with gold nanoparticles (AuNPs) and graphene oxide (GO) in order to enhance its sensitivity. UV-Visible spectrophotometer and high-resolution transmission electron microscope (HR-TEM) were used to characterize the AuNPs solution and GO aqueous dispersion. The absorbance spectrum of AuNPs and GO are recorded at 519 nm and 230 nm, respectively. The coating of AuNPs and GO over fiber surface were verified by using a scanning electron microscope (SEM) and energy-dispersive X-ray spectroscopy (EDX). Thereafter, sensor probe was functionalized with the specific enzyme i.e. uricase for the UA detection. The linearity response of uricase/GO/AuNPs-coated micro-ball optical fiber sensor is reported in the range of 10 µM - 1 mM UA concentrations. The reflectance of sensor linearly decreases with the increasing UA concentrations. Sensitivity of the sensor is 2.1 %/mM with a good slope of linearity with detection limit of 65.60 µM. To test the accuracy of proposed sensor, UA concentration in serum samples have also tested by using proposed sensor and A5800 Automatic Biochemical Analyzer. The results of the developed sensor are consistent with the results of A5800 Automatic Biochemical Analyzer. Thus, proposed sensor can be successfully utilized for UA detection in human serum samples.

5.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 27(5): 1469-1475, 2019 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-31607300

RESUMO

OBJECTIVE: To investigate the effect of LNK gene silencing and overexpression on the expression of STAT3 gene in human monocytic leukemia cells (THP-1). METHODS: THP-1 cells were cultured, and the lentivirus was used as a vector to silence and overexpres the LNK gene stably. After transfection for 72 hours, the GFP expression levels were observed by inverted fluorescence microscopy. The lentiviral transfection efficiencies were detected by flow cytometry. The effects of LNK silencing and overexpression were confirmed, and the expression of STAT3 mRNA was detected by RT-PCR. The protein levels of LNK and STAT3 were detected by Western blotting. RESULTS: The GFP expression level of THP-1 cells reached more than 85% after transfection with lentivirus for 72 hours, and the transfection efficiency of cells was above 99%. mRNA expressions levels of LNK and STAT3 in LNK silencing group were signifycantly lower than those in control group, while LNK and STAT3 mRNA levels in the LNK overexpression group was significantly higher than those in control group (P<0.05). The protein expression levels of LNK and STAT3 in LNK silencing group were significantly lower than those in control group, while that in LNK overexpression group was significantly higher than that in control group (P<0.05). CONCLUSION: The THP-1 cell line with LNK gene silencing and overexpression has been successfully established. The LNK gene silencing resulted in decrease of STAT3 expression; LNK gene overexpression and leads to inereases of STAT3 expression indicating that LNK participates in the regulation of STAT3.


Assuntos
Fator de Transcrição STAT3/metabolismo , Linhagem Celular Tumoral , Inativação Gênica , Vetores Genéticos , Humanos , Peptídeos e Proteínas de Sinalização Intracelular , Lentivirus , Proteínas , RNA Interferente Pequeno , Células THP-1 , Transfecção
6.
Chem Commun (Camb) ; 55(85): 12817-12820, 2019 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-31595889

RESUMO

Recently, water-in-salt electrolytes have been widely reported because of their ability in broadening the potential window of aqueous based energy storage devices. Herein, another eco-friendly and cost-effective electrolyte, concentrated potassium formate of 40 M HCOOK where the water-to-salt molar ratio falls to 1.38 : 1, is proposed. The electrolyte demonstrates a wide potential window of up to 4 V (-2.5 to 1.5 V vs. Ag/AgCl) with a glassy carbon electrode. Compared with a CH3COOK based electrolyte, the HCOOK possesses lower stable negative potential and higher ionic conductivity. For an activated carbon based supecapacitive electrode, a low discharge potential of -2.4 V vs. Ag/AgCl can be achieved. Besides, a high capacity of 321 F g-1 is obtained at 5 A g-1 and it is still as high as 121 F g-1 at 20 A g-1. Meanwhile, typical K-battery behavior is exhibited for the KTi2(PO4)3 anode and a reversible capacity of 15 mA h g-1 can be delivered at 0.1 A g-1.

7.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 27(4): 1013-1019, 2019 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-31418350

RESUMO

OBJECTIVE: To investigate the effect of silencing LNK gene on the expression of EPO and EPOR in acute myeloid leukemia cells (THP-1). METHODS: THP-1 cells were cultured. The lentivirus was used as a vector to silence the LNK gene stably. After 72 hours of infection, GFP expression level was detected by the fluorescent inverted microscopy. The lentiviral Infection efficiencies were monitored by flow cytometry. The LNK silencing effect was confirmed. The mRNA expressions of EPO and EPOR were detected by RT-PCR. The protein levels of LNK, EPO and EPOR were detected by Western blot. RESULTS: At the time-point of 72 hours after lentivirus infection, the expression level of GFP was above 85% detected by fluorescent inverted microscopy. The infection efficiency was above 99% by flow cytometry. mRNA expressions of LNK, EPO and EPOR in LNK silencing group were signifycantly lower than those in control group (P<0.05). The protein levels of LNK, EPO and EPOR in LNK silencing group were significantly lower than those in the control group (P<0.05). CONCLUSION: THP-1 cell line of LNK gene silencing has been successfully established,the LNK gene has been silenced, the expression of EPO and EPOR decrease, indicating that LNK may participate in the regulation of EPO and EPOR.


Assuntos
Proteínas/genética , Western Blotting , Eritropoetina , Inativação Gênica , Humanos , Peptídeos e Proteínas de Sinalização Intracelular , Receptores da Eritropoetina , Células THP-1
8.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 27(4): 1026-1032, 2019 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-31418352

RESUMO

OBJECTIVE: To investigate the expression of erythropoietin (EPO) and erythropoietin receptor (EPOR) in patients with acute leukemia (AL) and its clinical significance. METHODS: The levels of EPO and EPOR in plasma were determined by ELISA kit. mRNA expression levels of EPO and EPOR were determined by RT-RCR. The protein expression levels of EPO and EPOR were detected by Western blot. RESULTS: The EPO protein levels in marrow plasma of ALL and AML group were significantly higher than those in the control group (P<0.05), EPOR protein levels in ALL and AML group were significantly lower than those in the control group (P<0.05). The mRNA levels of EPO and EPOR in ALL and AML groups were significantly higher than those in the control group (P<0.05). The mRNA levels of EPO and EPOR in the high risk ALL and AML groups were significantly higher than those in the medium, low risk group and the control group (P<0.05). The protein expression levels of EPO and EPOR in ALL and AML groups were significantly higher than that in control group (P<0.05). The mRNA levels of EPO and EPOR in ALL and AML groups did not correlate with hemoglobin level and erythrocyte count (P>0.05). CONCLUSION: The expressions of EPO and EPOR is higher in ALL and AML patients. The expression levels of EPO and EPOR relate with the risk of ALL and AML. High risk patients have higher expression levels of EPO and EPOR, however, the expression levels of EPO and EPOR do not correlate with hemoglobin level and erythrocyte counting.


Assuntos
Leucemia Mieloide Aguda , Medula Óssea , Eritropoetina , Expressão Gênica , Humanos , Receptores da Eritropoetina
9.
ACS Nano ; 13(8): 9091-9099, 2019 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-31393706

RESUMO

While pseudocapacitive electrodes have potential to store more energy than electrical double-layer capacitive electrodes, their rate capability is often limited by the sluggish kinetics of the Faradaic reactions or poor electronic and ionic conductivity. Unlike most transition-metal oxides, MoO2 is a very promising material for fast energy storage, attributed to its unusually high electronic and ionic conductivity; the one-dimensional tunnel is ideally suited for fast ionic transport. Here we report our findings in preparation and characterization of ultrathin MoO2 sheets with oriented tunnels as a pseudocapacitive electrode for fast charge storage/release. A composite electrode consisting of MoO2 and 5 wt % GO demonstrates a capacity of 1097 C g-1 at 2 mV s-1 and 390 C g-1 at 1000 mV s-1 while maintaining ∼80% of the initial capacity after 10,000 cycles at 50 mV s-1, due to minimal change in structural features of the MoO2 during charge/discharge, except a small volume change (∼14%), as revealed from operando Raman spectroscopy, X-ray analyses, and density functional theory calculations. Further, the volume change during cycling is highly reversible, implying high structural stability and long cycling life.

10.
Molecules ; 24(15)2019 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-31366093

RESUMO

Phytochemical investigation of the aerial parts of Pteris cretica led to the isolation and elucidation of nine pterosins, including four new pterosins, creticolacton A (1), 13-hydroxy-2(R),3(R)-pterosin L (2), creticoside A (3), and spelosin 3-O-ß-d-glucopyranoside (4), together with five known pterosins 5-9. Their structures were identified mainly on the basis of 1D and 2D NMR spectral data, ESI-MS and literature comparisons. Compounds 1 and 3 were new type of petrosins with a six membered ring between C-14 and C-15. The new compounds were tested in vitro for their cytotoxic activities against four human tumor cell lines (SH-SY5Y, SGC-7901, HCT-116, Lovo). Results showed that compounds 1 and 2 exhibited cytotoxic activity against HCT-116 cells with IC50 value of 22.4 µM and 15.8 µM, respectively.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Citotoxinas/farmacologia , Indanos/farmacologia , Pteris/química , Sesquiterpenos/farmacologia , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Citotoxinas/química , Citotoxinas/isolamento & purificação , Células HCT116 , Humanos , Indanos/química , Indanos/isolamento & purificação , Concentração Inibidora 50 , Componentes Aéreos da Planta/química , Extratos Vegetais/química , Sesquiterpenos/química , Sesquiterpenos/isolamento & purificação , Relação Estrutura-Atividade
11.
Nutr Cancer ; : 1-11, 2019 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-31298947

RESUMO

We conducted a meta-analysis to evaluate the association between fat intake and the risk of three major types of skin cancer including basal cell carcinoma (BCC), squamous cell carcinoma (SCC) and cutaneous malignant melanoma (CMM). A comprehensive search of PubMed and EMBASE was performed to identify all relevant observational studies published up to December 1, 2018. Specific odds ratio (OR) or relative risk (RR) estimates for the highest versus the lowest intake of dietary fat and 95% confidence intervals (CI) from the included studies were pooled using random effect model. Three prospective cohort studies (175,675 participants and 30,915 BCC cases, 4,106 SCC cases and 1,638 CMM cases) and nine case-control studies (328 BCC cases, 493 SCC cases, 1,547 CMM cases and 2,660 controls) were identified. The pooled results indicated that dietary consumption of total fat and saturated fat were not associated with three major types of skin cancer. High consumption of monounsaturated fat was significantly associated with a decreased risk of BCC (RR: 0.90, 95% CI: 0.85-0.96) and high level of polyunsaturated fat intake was potentially positively associated with SCC (RR: 1.19, 95% CI: 1.06-1.33). Our findings should be confirmed by further evidence from well-designed and large-scale prospective cohort studies.

12.
Curr Mol Med ; 19(7): 525-531, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31195943

RESUMO

OBJECTIVE: We aimed to investigate the potential risk factors for residual lesions after uterine artery chemotherapy and embolization (UACE) in combination with dilatation and curettage (D&C) in patients with cesarean scar pregnancy (CSP). SETTINGS: Retrospective case-control study. METHOD: Univariate analysis and logistic analysis were applied to analyze these data to assess the risk factor of residue after UACE in combination with D&C. RESULTS: Gestational age, human chorionic gonadotropin (HCG) level, and the gestation sac (GS) evagination to the bladder were the risk factors for the postoperative lesion. The most relevant was GS evagination to the bladder, followed by the preoperative HCG level and the gestational age. We defined the cut-off value of gestational age as 28 days with a sensitivity and specificity of 100 and 0, respectively. CONCLUSION: In cases with GS evagination to bladder and HCG of >28,113.65 mIU/ml as well as a gestational age of >28 days, the possibility of residual lesions was high.

13.
Appl Biochem Biotechnol ; 189(2): 448-458, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31044370

RESUMO

For efficiently enhancing the activity of isoeugenol monooxygenase, a whole cell overproducing active aggregate IEM720-18A was successfully fabricated via the fusion of amphiphilic short peptide 18A (EWLKAFYEKVLEKLKELF) and isoeugenol monooxygenase and then efficiently expressed in E. coli BL21 (DE3). Such resulting bacteria, E. coli BL21 (DE3) harboring pET30a-IEM720-18A was applied in the biotransformation of isoeugenol to vanillin with the optimization of cultivation conditions. Our results revealed that the vanillin concentration reached to the highest level (14.5 mmol/L) under the optimized reaction conditions including 1.5-g cells containing active aggregate of IEM720-18A, 10% (v/v) dimethyl sulfoxide (DMSO), 100 mmol/L isoeugenol, 50 mmol/L glycine-sodium hydroxide buffer (pH 10.5) in 10 mL reaction volume, and 200 rpm at 25 °C for 36 h. Moreover, the active aggregate IEM720-18A was immobilized with 100 mmol/L glutaraldehyde at 4 °C to improve the operational stability. The highest activity could be achieved when the reactions were carried out at 25 °C and the relative activity of the immobilized enzyme maintained over 60% after seven recycles. Our study provides a new approach to the biotransformation of isoeugenol into vanillin.


Assuntos
Benzaldeídos/metabolismo , Células Imobilizadas/metabolismo , Escherichia coli/metabolismo , Eugenol/análogos & derivados , Escherichia coli/genética , Eugenol/metabolismo
14.
Biol Res ; 52(1): 11, 2019 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-30876449

RESUMO

BACKGROUND: The present study aimed to investigate the underlying role of interferon-regulatory factor 2 (IRF2)-inositol polyphosphate-4-phosphatase, type-II (INPP4B) axis in the regulation of autophagy in acute myeloid leukemia (AML) cells. METHODS: Quantitative real time PCR (QRT-PCR) and western blot were performed to determine the expression levels of IRF2, INPP4B and autophagy-related markers in AML cell lines. Autophagy was assessed by elevated Beclin-1 expression, the conversion of light chain 3 (LC3)-I to LC3-II, downregulated p62 expression and green fluorescent protein (GFP)-LC3 puncta formation. The colony formation and apoptosis assays were performed to determine the effects of IRF2 and INPP4B on the growth of AML cells. RESULTS: IRF2 and INPP4B were highly expressed in AML cell lines, and were positively correlated with autophagy-related proteins. Overexpression of IRF2 or INPP4B stimulated autophagy of AML cells, whereas inhibition of IRF2 or INPP4B resulted in the attenuation of autophagy. More importantly, IRF2 or INPP4B overexpression reversed autophagy inhibitor, 3-methyladenine (3-MA)-induced proliferation-inhibitory and pro-apoptotic effects, while IRF2 or INPP4B silencing overturned the proliferation-promoting and anti-apoptotic effects of autophagy activator rapamycin. CONCLUSION: IRF2-INPP4B signaling axis attenuated apoptosis through induction of autophagy in AML cells.


Assuntos
Apoptose , Autofagia , Fator Regulador 2 de Interferon/metabolismo , Leucemia Mieloide Aguda/metabolismo , Monoéster Fosfórico Hidrolases/metabolismo , Western Blotting , Linhagem Celular Tumoral , Proliferação de Células , Imunofluorescência , Humanos , Leucemia Mieloide Aguda/patologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Transdução de Sinais
15.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 27(1): 45-51, 2019 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-30738446

RESUMO

OBJECTIVE: To investigate the expression of STAT3 gene in patients with acute myeloid leukemia and its correlation with clinical characteristics. METHODS: The real-time quantitative RT-PCR was used to detect the level of STAT3 mRNA in bone marrow samples from 38 newly diagnosed patients with acute myeloid leukemia(AML), and its relevance with clinical characteristics and prognosis were statistically analyzed. Western blot was employed to detect the STAT3 protein level in AML patients. The bone marrow cells from 15 healthy subjects were used as control. RESULTS: At the mRNA level, the expression level of STAT3 in the AML group was significantly higher than that in control group (P<0.05). The level of STAT3 in AML group correlated positively with the risk factors of patients (P<0.01,r=0.592). The STAT3 expression level in the high-risk group was statistically higher than that in the standard-risk group and the control group (P<0.01,P<0.01). Furthermor, there was no statistical difference between the sub-groups of AML (P>0.05). The median survival time of patients in STAT3 low expression group was logner than that in high expression group, but the difference was not statistically significant (P>0.005). The level of STAT3 protein in AML patients was significantly higher than that in control group (P<0.05). CONCLUSION: The STAT3 gene is highly expressed in AML patients, which may be used as a predictor for high-risk of AML.


Assuntos
Leucemia Mieloide Aguda , Fator de Transcrição STAT3/genética , Medula Óssea , Humanos , Prognóstico , RNA Mensageiro
16.
Asian J Androl ; 21(2): 170-176, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30409959

RESUMO

Pelvic floor muscle exercise (PFME) is the most common conservative management for urinary incontinence (UI) after radical prostatectomy (RP). However, whether the PFME guided by a therapist (G-PFME) can contribute to the recovery of urinary continence for patients after RP is still controversial. We performed this meta-analysis to investigate the effectiveness of G-PFME on UI after RP and to explore whether the additional preoperative G-PFME is superior to postoperative G-PFME alone. Literature search was conducted on Cochrane Library, Embase, Web of Science, and PubMed, to obtain all relevant randomized controlled trials published before March 1, 2018. Outcome data were pooled and analyzed with Review Manager 5.3 to compare the continence rates of G-PFME with control and to compare additional preoperative G-PFME with postoperative G-PFME. Twenty-two articles with 2647 patients were included. The continence rates of G-PFME were all superior to control at different follow-up time points, with the odds ratio (OR) (95% confidence interval [CI]) of 2.79 (1.53-5.07), 2.80 (1.87-4.19), 2.93 (1.19-7.22), 4.11 (2.24-7.55), and 2.41 (1.33-4.36) at 1 month, 3 months, 4 months, 6 months, and 12 months after surgery, respectively. However, there was no difference between additional preoperative G-PFME and postoperative G-PFME, with the OR (95% CI) of 1.70 (0.56-5.11) and 1.35 (0.41-4.40) at 1 month and 3 months after RP, respectively. G-PFME could improve the recovery of urinary continence at both early and long-term stages. Starting the PFME preoperatively might not produce extra benefits for patients at early stage, compared with postoperative PFME.

17.
Biol. Res ; 52: 11, 2019. graf
Artigo em Inglês | LILACS-Express | ID: biblio-1011413

RESUMO

Abstract Background: The present study aimed to investigate the underlying role of interferon-regulatory factor 2 (IRF2)-inositol polyphosphate-4-phosphatase, type-II (INPP4B) axis in the regulation of autophagy in acute myeloid leukemia (AML) cells. Methods: Quantitative real time PCR (QRT-PCR) and western blot were performed to determine the expression levels of IRF2, INPP4B and autophagy-related markers in AML cell lines. Autophagy was assessed by elevated Beclin-1 expression, the conversion of light chain 3 (LC3)-I to LC3-II, downregulated p62 expression and green fluorescent protein (GFP)-LC3 puncta formation. The colony formation and apoptosis assays were performed to determine the effects of IRF2 and INPP4B on the growth of AML cells. Results: IRF2 and INPP4B were highly expressed in AML cell lines, and were positively correlated with autophagy-related proteins. Overexpression of IRF2 or INPP4B stimulated autophagy of AML cells, whereas inhibition of IRF2 or INPP4B resulted in the attenuation of autophagy. More importantly, IRF2 or INPP4B overexpression reversed autophagy inhibitor, 3-methyladenine (3-MA)-induced proliferation-inhibitory and pro-apoptotic effects, while IRF2 or INPP4B silencing overturned the proliferation-promoting and anti-apoptotic effects of autophagy activator rapamycin. Conclusion: IRF2-INPP4B signaling axis attenuated apoptosis through induction of autophagy in AML cells.

18.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 26(6): 1649-1656, 2018 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-30501699

RESUMO

OBJECTIVE: To explore the change of G6PD activity in children with acute leukemia(AL)and its correlation with the clinical characteristics. METHODS: The G6PD activity in peripheral blood samples from 74 children disagnosed as AL (50 cases of ALL, and 24 cases of AML) was detected by Zinkham method recommended by WHO in 1967, and its relevance with clinical indicators was statistically analyzed. The peripheral blood samples of 70 healthy children were used as the controls. RESULTS: The G6PD activity in ALL and AML groups was significantly lower than that in the control group (P=0.000, P=0.000) and there was no statistical difference between ALL and AML groups. The G6PD activity in bacterial, fungal infection and non-infection groups (no bacterial and fungal infection) were statistically different from control group (P=0.02, P=0.001, P=0.001), respectively. The G6PD activity in bacterial infection group and non-infection group was statistically different from with fungal infection group (P=0.004, P=0.019), respectively. The G6PD activity linearly correlated with leukocyte count and neutrophil percentage in AL children (P=0.000, P=0.001, r=0.465, r=0.434), respectively. The median survival time of G6PD activity deficiency group was higher than that in the normal group, but without statistically significant difference (P=0.4149). CONCLUSION: The G6PD activity in AL children is significantly lower than that in healthy children, and the G6PD activity linearly relates with leukocyte count and neutrophil percentage of AL children. The patients with G6PD activity deficiency is more susceptible to fungal infection, moreover the infection is more serious.


Assuntos
Deficiência de Glucosefosfato Desidrogenase , Leucemia Mieloide Aguda , Doença Aguda , Infecções Bacterianas , Criança , Glucosefosfato Desidrogenase , Humanos , Neutrófilos
19.
ACS Appl Mater Interfaces ; 10(49): 42524-42533, 2018 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-30427173

RESUMO

Transition metal dichalcogenides (TMDs) have attracted much attention due to their promising optical, electronic, magnetic, and catalytic properties. Engineering the defects in TMDs represents an effective way to achieve novel functionalities and superior performance of TMDs devices. However, it remains a significant challenge to create defects in TMDs in a controllable manner or to correlate the nature of defects with their functionalities. In this work, taking single-layer MoS2 as a model system, defects with controlled densities are generated by 500 keV Au irradiation with different ion fluences, and the generated defects are mostly S vacancies. We further show that the defects introduced by ion irradiation can significantly affect the properties of the single-layer MoS2, leading to considerable changes in its photoluminescence characteristics and electrocatalytic behavior. As the defect density increases, the characteristic photoluminescence peak of MoS2 first blueshifts and then redshifts, which is likely due to the electron transfer from MoS2 to the adsorbed O2 at the defect sites. The generation of the defects can also strongly improve the hydrogen evolution reaction activity of MoS2, attributed to the modified adsorption of atomic hydrogen at the defects.

20.
ACS Appl Mater Interfaces ; 10(46): 39785-39793, 2018 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-30372019

RESUMO

Electrode materials with high activity and good stability are essential for commercialization of energy conversion systems such as solid oxide fuel cells or electrolysis cells at the intermediate temperature. Modifying the existing perovskite-based electrode surface to form a heterostructure has been widely applied for the rational design of novel electrodes with high performance. Despite many successful developments in enhancing electrode performance by surface modification, some controversial results are also reported in the literature and the mechanisms are still not well understood. In this work, the mechanism of how surface modification impacts the oxygen reduction reaction (ORR) activity and stability of perovskite-based oxides was investigated. We took La0.6Sr0.4Co0.2Fe0.8O3 (LSCF) as the thin-film model system and modified its surface with additive Pr xCe1- xO2 layers of different thicknesses. We found a strong correlation between surface oxygen defects and the ORR activity of the heterostructure. By inducing higher oxygen vacancy concentration compared to bare LSCF, PrO2 coating is proved to greatly facilitate the rate of oxygen dissociation, thus significantly enhancing the ORR activity. Because of low oxygen vacancy density introduced by Pr0.2Ce0.8O2 and CeO2 coating, on the one hand, it does not boost the rate of ORR but successfully suppresses surface Sr segregation, leading to an enhanced durability. Our findings demonstrate the vital role of surface oxygen defects and provide important insights for the rational design of high-performance electrode materials through surface defect engineering.

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