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1.
J Phys Condens Matter ; 32(3): 035502, 2020 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-31553961

RESUMO

Using the first-principles calculation, we systematically studied the electronic properties of the bilayer transition metal dichalcogenides (TMDs) MX2 (M = Mo, W; X = S, Se, Te) with replacing one, two, three or four layers of X atoms as Y atoms (X ≠ Y = S, Se, Te). By comparison, it is found that when the inner two layers of chalcogenide atoms are different, the system has both valence band offset (VBO) and conduction band offset (CBO). Among them, values of the band offsets reach maxima when the inner one layer of X atoms is replaced by Y atoms, namely forming the asymmetric Janus bilayer XMX/YMX. We take SMoS/SeMoS as an example to analyze the formation of the band offsets and the improvement of optoelectronic properties. Importantly, it is also found that both external electric field and biaxial strain can regulate electronic structures of asymmetric Janus bilayer TMDs with noticeable modulation of the values of band offsets. When the external electric field changes from negative to positive continually, CBO decreases and VBO increases. While when the biaxial strain changes from compression to stretch continually, CBO increases and VBO decreases. These findings enrich the study of bilayer TMDs that can be used as optoelectronic, nanoelectronic and valleytronic devices.

2.
Sci Total Environ ; 698: 134289, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31514034

RESUMO

Microeukaryotes are the key ecosystem drivers mediating marine productivity, the food web and biogeochemical cycles. The northwestern Pacific Ocean (NWPO), as one of the world's largest oligotrophic regions, remains largely unexplored regarding diversity and biogeography of microeukaryotes. Here, we investigated the community composition and geographical distribution of microeukaryotes collected from the euphotic zone of three different regions in the NWPO using high-throughput sequencing of the 18S rRNA gene and quantified the contributions of environmental factors on the distributions of microeukaryotes. The relative abundance of different group taxa, except for Ciliophora, presented distinct patterns in each region, and Metazoa and Dinoflagellata dominated the community, contributing approximately half of reads abundance. Spatial and environmental factors explained 66.01% of community variation in the NWPO. Temperature was the most important environmental factor significantly correlated with community structure. Bacterial biomass was also significantly correlated with microeukaryotic distribution, especially for Dinoflagellata and Diatomea. Network analysis showed strong correlations between microeukaryotic groups and free-living bacteria and different bacterial taxa were correlated with specific microeukaryotic groups, indicating that their interactions enabled microeukaryotic groups to adapt to diverse environments. This study provides a first glance at the diversity and geographical distribution of microeukaryotes in the NWPO and sheds light on the biotic and abiotic factors in shaping the microeukaryotic community in the ocean.

3.
BMC Cancer ; 19(1): 1061, 2019 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-31703584

RESUMO

BACKGROUND: To reveal roles of reactive oxygen species (ROS) status in chemotherapy resistance and to develop a ROS scoring system for prognosis prediction in ovarian cancer. METHODS: We tested the sensitizing effects of ROS elevating drugs to cisplatin (cDDP) in ovarian cancer both in vitro and in vivo. A ROS scoring system was developed using The Cancer Genome Atlas (TCGA) database of ovarian cancer. The associations between ROS scores and overall survival (OS) were analyzed in TCGA, Tothill dataset, and our in-house dataset (TJ dataset). RESULTS: ROS-inducing drugs increased cisplatin-induced ovarian cancer cell injury in vitro and in vivo. ROS scoring system was established using 25 ROS-related genes. Patients were divided into low (scores 0-12) and high (scores 13-25) score groups. Improved patient survival was associated with higher scores (TCGA dataset hazard ratio (HR) = 0.43, P < 0.001; Tothill dataset HR = 0.65, P = 0.022; TJ dataset HR = 0.40, P = 0.003). The score was also significantly associated with OS in multiple datasets (TCGA dataset r2 = 0.574, P = 0.032; Thothill dataset r2 = 0.266, P = 0.049; TJ dataset r2 = 0.632, P = 0.001) and with cisplatin sensitivity in ovarian cancer cell lines (r2 = 0.799, P = 0.016) when used as a continuous variable. The scoring system showed better prognostic performance than other clinical factors by receiver operating characteristic (ROC) curves (TCGA dataset area under the curve (AUC) = 0.71 v.s. 0.65, Tothill dataset AUC = 0.73 v.s. 0.67, TJ dataset AUC = 0.74 v.s. 0.66). CONCLUSIONS: ROS status is associated with chemotherapy resistance. ROS score system might be a prognostic biomarker in predicting the survival benefit from ovarian cancer patients.

4.
Artigo em Inglês | MEDLINE | ID: mdl-31723084

RESUMO

PURPOSE: Stanford type A aortic dissection (TAAD) is one of the most dangerous cardiovascular diseases. MicroRNAs (miRNAs) have been considered as potential therapeutic targets for TAAD. In this present study, we aimed to investigate the functional role and regulatory mechanism of miR-26b in TAAD development. MATERIALS AND METHODS: MiR-26b mRNA expression was detected by real-time polymerase chain reaction (RT-PCR) and protein levels were measured by Western blot. Verifying the direct target of miR-26b was used by dual luciferase assay, RT-PCR, and Western blot. Cell Counting Kit-8 (CCK-8) and TUNEL staining assays were applied for detecting rat aortic vascular smooth muscle cells (VSMCs) viability and apoptosis, respectively. RESULTS: We found that miR-26b was under-expressed in TAAD patients and closely associated with the poor prognosis of TAAD patients. Re-expression of miR-26b facilitated while knockdown of miR-26b inhibited VSMC proliferation. However, miR-26b showed the opposite effect on cell apoptosis. More importantly, high-mobility group AT-hook 2 (HMGA2) was verified as the direct target of miR-26b. Furthermore, transforming growth factor beta (TGF-ß)/Smad3 signaling pathway was involved in the development of TAAD modulated by miR-26b. CONCLUSION: miR-26b impeded TAAD development by regulating HMGA2 and TGF-ß/Smad3 signaling pathway, which provided a potential biomarker for TAAD treatment.

5.
Int Wound J ; 2019 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-31701658

RESUMO

The objective of this study is to investigate the mechanism whereby innate immune molecule surfactant protein D (SP-D) attenuates sepsis-induced acute kidney injury (AKI) through modulating apoptosis and nuclear factor kappa-B (NFκB)-mediated inflammation. In the present study, a mouse sepsis model was established by cecal ligation and puncture in SP-D knockout (KO) mice and wild-type (WT) mice. A sham-operated group was included as the control. The experimental materials were extracted 6 and 24 hours postoperatively. The plasma levels of tumour necrosis factor alpha (TNF-α) and MCP-1 were determined by enzyme-linked immunosorbent assay (ELISA). Apoptosis was measured by double staining with Annexin V/propidium iodide and flow cytometry. The levels of NFκB in renal tissues were measured by ELISA and Western blotting assay. Apoptosis was detected by TUNEL assays. There were no significant differences in plasma TNF-α levels between the WT sham group and the KO sham group at 6 and 24 hours postoperatively (P < .05), but the levels of TNF-α in the WT sepsis and KO sepsis groups were significantly higher than those in controls (P < .05). The levels of TNF-α in the KO sepsis group were significantly higher than those of the WT sepsis group (P < .05). TNF-α levels in the WT sepsis group and the KO sepsis group at 24 hours postoperatively were significantly higher than those at 6 hours postoperatively (P < .05). The levels of MCP-1 in the WT sepsis group and the KO sepsis group at 6 and 24 hours postoperatively were significantly higher than those in the control group (P < .05), and MCP-1 levels in the KO sepsis group were significantly higher than those in the WT sepsis group (P < .05). MCP-1 levels in the WT sepsis group and the KO sepsis group at 24 hours postoperatively were significantly higher than those at 6 hours postoperatively (P < .05). The expression of SP-D in WT kidneys was significantly lower at 6 and 24 hours postoperatively (P < .05). The number of TUNEL-positive cells in the kidneys from septic SP-D KO mice was significantly higher (P < .05). The levels of NFκB in septic mice were significantly increased at 6 and 24 hours after induction of sepsis compared with the sham-operated group compared with those of septic SP-D KO mice and WT mice (P < .05). Innate immune molecule SP-D significantly decreased plasma levels of inflammatory cytokines in mice and attenuated sepsis-induced AKI by inhibiting NFκB activity and apoptosis.

6.
Chem Commun (Camb) ; 55(95): 14279-14282, 2019 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-31709445

RESUMO

This study proposes a novel strategy for preparing Ti-Beta zeolite with nanosized crystals and incredibly stable isolated Ti4+ ions under solvent-free conditions via intensified interzeolite transformation from a commercially available Ti-MWW source. The obtained Ti-Beta exhibited unique catalytic performance in the oxidation of cyclohexene with aqueous hydrogen peroxide.

7.
J Toxicol Environ Health A ; 82(19): 1036-1044, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31736438

RESUMO

An extract of Dracocephalum moldevica (DML) was found to exert protective effects on cerebral ischemia-reperfusion injury (CIRI); however, the mechanisms underlying the observed actions of this plant-derived mixture remain to be determined. Thus, the aim of this study was to examine the influence of DML on CIRI rat model induced by middle cerebral artery occlusion (MCAO). The following parameters were measured: (1) viable neurons in the infarcted area using Nissl staining; and (2) immunohistochemistry and Western blot were employed to determine protein expression levels of p53, bcl-2 associated X protein (bax) and B-cell lymphoma-2 (bcl-2), three biomarkers of apoptosis. MCAO significantly decreased the number of viable cortical pyramidal neurons in the infarcted area, while treatment with DML extract significantly elevated the number of viable neurons. MCAO was found to significantly elevate in gene expression levels of p53 and protein expression levels bax accompanied by diminished protein expression levels of bcl-2. Prior administration of DML extract produced marked reduction in gene expression levels of p53 and protein expression levels bax but increased in protein expression levels of bcl-2. Data suggested apoptosis was initiated in MCAO and that DML was effective in treating CIRI via an anti-apoptotic action as evidenced by inhibition of gene expression levels of p53 and protein expression levels of bax with concomitant elevation in protein expression levels of bcl-2. Our findings suggest that extract of DML may prove beneficial in treatment of cerebrovascular disorders.

8.
J Hazard Mater ; : 121593, 2019 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-31744726

RESUMO

Hierarchical ZSM-5 zeolite with meso- and micro-pore structures was successfully prepared through a facile one-pot hydrothermal synthesis method using bifunctional template. After copper ion-exchange, it was applied for the selective catalytic reduction of NO with NH3 (NH3-SCR). Compared with conventional Cu-ZSM-5 catalyst containing only micropores, the hierarchical catalyst with ca. 2 wt.% Cu loading displayed significantly improved catalytic performance. Particularly, the hierarchical zeolite catalyst also displayed excellent hydrothermal stability and sulfur resistance that exhibited great potential in practical application. Characterization techniques such as XRD, N2 physisorption, temperature programmed desorption/reduction (TPD/TPR) and in situ diffuse reflectance infrared Fourier transform spectroscopy (in situ DRIFTS) were comprehensively used to reveal the relationship between zeolite structure and catalytic properties. It was concluded that the hierarchically porous structure could not only improve the mass transfer of reactant/product but also provide larger specific surface area, higher surface acidity, larger NO adsorption capacity. And we found that bidentate nitrate species was more active in Cu-ZSM-5-meso than Cu-ZSM-5-C, which were all beneficial to the NH3-SCR reaction. This work can provide a guideline to design other high performance hierarchical zeolites with different crystalline structures (such as CHA, LTA) for efficient catalytic NOx removal processes.

9.
J Am Chem Soc ; 2019 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-31746191

RESUMO

Multiscale simulations have been performed to address the longstanding issue of the "dioxygen activation" by the binucle-ar copper monooxygenases (PHM and DßM), which were traditionally classified as the "noncoupled" binuclear copper enzymes. Our QM/MM calculations rule out that CuM(II)-O2• is an active species for H-abstraction from the substrate. By contrast, CuM(II)-O2• would abstract an H atom from the co-substrate ascorbate to form a CuM(II)-OOH intermediate in PHM and DßM. Consistent with the recently reported structural features of DßM, the umbrella sampling shows that the "open" conformation of CuM(II)-OOH intermediate could readily transform into the "closed" conformation in PHM, in which we located a mixed-valent µ-hydroperoxodicopper(I,II) intermediate, (µ-OOH)Cu(I)Cu(II). The subsequent O-O cleavage and OH moiety migration to CuH generate an unexpected species of (µ-O)(µ-OH)Cu(II)Cu(II), which is revealed to be the reactive intermediate responsible for substrate hydroxylation. We also demonstrate that the flexible Met ligand is favorable for O-O cleavage reaction, while the replacement of Met with the strongly bound His ligand would inhibit the O-O cleavage reactivity. As such, the study not only demonstrates a "coupled" mechanism for O2 activation by binuclear cop-per monooxygenases, but also deciphers the full catalytic cycle of PHM and DßM in accord with the available experimental data. These findings of O2 activation and substrate hydroxylation by binuclear copper monooxygenases could expand our understandings on the reactivities of the synthetic mono-copper complexes.

10.
Artigo em Inglês | MEDLINE | ID: mdl-31674090

RESUMO

A novel crystalline high-silica zeolite with 12×8-membered ring (R) channel system is prepared with the aid of the 3D electron diffraction (3D ED) technique. A crystal with the same topology as one of the predicted daughter structures of CIT-13 germanosilicate, named ECNU-23 (East China Normal University 23) was coincidentally detected by the 3D ED investigation during the structure characterization of the "pure" powder sample of existing one-dimension (1D) 10-R ECNU-21. By controlling the alkaline-assisted hydrolysis under moderate conditions, we purified the phase of ECNU-23 by selectively breaking and removing the chemically weak Ge(Si)-O-Ge and metastable Si-O-Si bonds. Its structure was determined based on the 3D ED data, and confirmed by high-resolution TEM images and powder X-ray diffraction (PXRD) data. The aluminosilicate Al-ECNU-23 shows unique catalytic properties in the isomerization/ disproportionation of m-xylene as solid-acid catalyst.

13.
Medicine (Baltimore) ; 98(44): e17749, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31689829

RESUMO

RATIONALE: Early infantile epileptic encephalopathy (EIEE) 65 was recently shown to be caused by the cytoplasmic FMRP interacting protein 2 (CYFIP2) mutation. To date, only 5 cases have been reported in two articles, and all the outcomes in all cases were poor. PATIENT CONCERNS: In this study, we reported an 8-month-old girl with a 1 month-long history of seizures and developmental delay. Over 1 month later, she developed epileptic spasms in clusters with hypsarrhythmia on electroencephalography. DIAGNOSIS: The patient was diagnosed with EIEE 65 and trio-based whole-exome sequencing revealed a causative de novo CYFIP2 mutation c.260G >T (p.Arg87Leu). INTERVENTIONS: The proband was successively treated with multiple antiepileptic drugs, including levetiracetam, phenobarbital, VitB6, topiramate, methylprednisolone, prednisone, valproic acid and vigabatrin. OUTCOMES: After resistance to multiple anti-epileptic drugs over 2 months of treatment, she finally achieved seizure-free several days after vigabatrin administration and her developmental delay steadily improved. LESSONS: OUR: case confirmed that CYFIP2 was the pathogenic gene of EIEE 65. We also first demonstrated vigabatrin might be effective for control of seizures and helpful for the improved outcomes of these patients.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/genética , Mutação/genética , Espasmos Infantis/genética , Anticonvulsivantes/uso terapêutico , Diagnóstico Precoce , Feminino , Humanos , Lactente , Espasmos Infantis/diagnóstico , Espasmos Infantis/tratamento farmacológico , Resultado do Tratamento
14.
ACS Nano ; 2019 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-31769964

RESUMO

Singlet oxygen (1O2) plays a central role in photochemical and photobiological research. Although many photosensitizers for efficient 1O2 generation were reported, further improving its yield and oxidation power is still highly desirable. Instead of developing new ones, current photosensitizers might be boosted by mediators to facilitate energy transfer. Taking advantage of the long triplet state lifetime of lanthanide ions (Ln3+), we herein demonstrate their roles as potent oxidation mediators. Using oxidation of 3,3',5,5'-tetramethylbenzidine (TMB) at neutral pH as a difficult model reaction, based on the fluorescence, phosphorescence, and metal-binding properties, various dyes and nanomaterials were classified into four types. The 1O2 emission of carbon dots and rose bengal enhanced 4 times in the presence of Ce3+. Some non-phosphorescent, but strongly fluorescent dyes that are not known as photosensitizers can still be mediated by Ln3+ to produce 1O2, but metal chelating calcein was not enhanced. Finally, non-emissive dyes failed to show activity. As mediators, the excited Ln3+ can migrate a long distance and transfer energy to O2, resulting in high 1O2 yield. Since redox active Ce3+ and Eu3+ had the highest activity, participation of oxidation involving excited lanthanides might be possible too. In addition, Ln3+ also enhanced the activity of graphene quantum dots, graphene oxide, and g-C3N4. Rapid degradation of organic dyes was demonstrated, further supporting a high photocatalytic activity of Ln3+-mediated system.

15.
Artigo em Inglês | MEDLINE | ID: mdl-31771181

RESUMO

Oxygen deficiency and coldness are the main challenges for highway tunnel construction in high-altitude areas such as western Sichuan plateau. The artificial oxygen supply and anti-freezing structure in the tunnel construction process has a significant impact on vocational health and the environment. Thus, the conditions of tunnels need to be carefully evaluated before construction. However, the current design code for tunnel construction contains few instructions about these aspects. This paper attempts to establish a simple evaluation method to guide the construction design by analyzing the oxygen partial pressure of trachea, the mean temperature of the coldest month, and the maximum freezing depth for tunnel projects in western Sichuan plateau. Based on the on-site meteorological monitoring at different altitudes of three typical tunnels in the western Sichuan plateau and the comparative analysis of the existing meteorological data, the corresponding relationships between the three parameters and the altitude were investigated. The thresholds by altitude for grading the tunnels are identified as 2100 m and 4200 m, respectively. The highway tunnels in the western Sichuan plateau are graded in three categories, namely, general-altitude tunnels, high-altitude tunnels, and ultra-high-altitude tunnels. The corresponding measures of oxygen supply and freezing prevention for different graded tunnels are recommended. The results would provide a basis for the design and construction of new tunnels and enhance the service life and operations safety of the tunnels in western Sichuan plateau and other similar high-altitude areas.

16.
ACS Appl Mater Interfaces ; 11(47): 44241-44248, 2019 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-31674181

RESUMO

Highly dispersed metallic silver nanoparticles (AgNPs) are promising heterogeneous catalysts for carboxylative coupling of terminal alkynes with CO2 under mild conditions. Yet, their size-controlled synthesis is very challenging because of the high surface energy. Here, we prepared a series of amino-functionalized ordered mesoporous polymers as hosts for anchoring AgNPs. Control experiments and computations showed that electron-rich amines were confined in mesochannels with varying electron density and steric hindrance, creating "localized active zones (LAZ)" to control the growth of AgNPs. The particle size of AgNPs grows along with the increased volume of LAZ around nitrogen species. We also revealed that the catalytic activity of Ag-based catalysts is size-dependent and increases with decreasing particle size. Building on these findings, we report a facile one-pot synthesis strategy for preparing an amine-incorporated ordered mesoporous polymer (NOMP) with a high specific surface area, small LAZ volume, and uniform amine sites with controllable loading. These features result in the formation of ultrasmall and monodispersed Ag nanoparticles. Remarkably, Ag@NOMP gave a quantitative target yield under the conditions of 1 atm CO2 pressure and 50 °C, showing superior catalytic activity in CO2 carboxylation compared to other mesoporous analogues.

17.
Cell Death Dis ; 10(12): 884, 2019 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-31767859

RESUMO

Recent studies have demonstrated that microRNA-155-5p (miR-155-5p) plays an essential role in the regulation of allergen-induced inflammation and is overexpressed in the skin of patients with atopic dermatitis (AD), although the mechanism is unknown. In this study, silencing miR-155-5p attenuated the thickening of the epidermis in AD model and reduced the infiltration of inflammatory cells and the secretion of Th2 cytokines. Protein kinase inhibitor α (PKIα) was identified as a direct target of miR-155-5p and correlated negatively with miR-155-5p in our AD model. Fluorescence in situ hybridization showed that miR-155-5p-expressing cells were predominantly present in the epidermis. When epithelial cells were transfected with an miR-155-5p inhibitor, the expression of PKIα, occludin, and CLDN16 increased and that of TSLP decreased significantly, whereas the overexpression of miR-155-5p resulted in the opposite changes. The increased expression of PKIα and tight junction (TJ) proteins, with reduced TSLP and IL-33, was also detected in miR-155-5p-blocked mice, in both the initial and elicitation stages of AD. The expression of TJ proteins also decreased when cells were transfected with PKIα siRNA. TJ proteins increased and TSLP and IL-33 decreased significantly after the overexpression of PKIα. Our data provide the first evidence that miR-155-5p is critical for the allergic inflammation in a mouse model of AD by directly regulating PKIα and thus epithelial TJ expression. These findings suggest new therapeutic strategies that target miR-155-5p in patients with allergic disorders.

18.
Ir J Med Sci ; 2019 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-31776834

RESUMO

OBJECTIVE: The objective of the study was to investigate the association between mitochondrial DNA (mtDNA) mutations and essential hypertension (EH). METHODS: One Han Chinese pedigree with maternally inherited EH was recruited in the current study. The matrilineal relatives from this family underwent clinical, genetic, and molecular analysis. Moreover, the mtDNA gene mutations were screened by PCR and direct Sanger sequence. Evolutionary conservation was performed and the secondary structure of mt-tRNASer(UCN) with and without the 7471delC was evaluated by the RNA Fold Webserver program. Moreover, the pathogenicity scoring system was used to assess the 7471delC. RESULTS: This Chinese pedigree exhibited a relative high penetrance and expressivity of EH. Of 13 matrilineal relatives, 5 of them suffered from high blood pressure (BP). Genetic analysis of the complete mtDNA genes showed the presence of a novel tRNASer(UCN) 7471delC, together with a set of polymorphisms belonging to the human mitochondrial haplogroup G2a1. In fact, the 7471delC occurred within the T-stem and extra arm of tRNASer(UCN), which was very conserved from bacteria to human mitochondria. Interestingly, the 7472insC which was located at the same position had been regarded as a pathogenic mutation associated with non-syndromic hearing loss. In addition, bioinformatics analysis revealed that the 7471delC affected the secondary structure of tRNASer(UCN). The pathogenicity scoring system showed that the 7471delC may be "possibly pathogenic" associated with EH. CONCLUSION: We believed that the 7471delC may impair the mitochondrial functional and played an active role in the pathogenesis of EH in this pedigree. The 7471delC may be a novel risk factor for maternally transmitted EH.

19.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 27(5): 1431-1435, 2019 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-31607294

RESUMO

OBJECTIVE: To investigate the efficacy and safety of decitabine combined with half-course pre-excitation for the treatment of elderly patients with acute myeloid leukemia (AML). METHODS: 44 cases of newly diagnosed elderly AML admitted in our hospital from January 2016 to December 2017 were selected for the retrospective analysis. The patients were randomly divided into 2 groups: pre-excitation therapy group as control and combined therapy group. The 22 patients in pre-excitation therapy group reccived the routine complete course pre-excitation treatment, 22 patients in combined therapy group received the desitabine combined the half course pre-excitation treatment. The therapentic efficacy and adverse reactions during treatment were compared between 2 groups. All patients were followed-up and the survival rate at 6,12 and 24 months was compared between 2 groups. RESULTS: The remission rate(RR) in the combined therapy group was 72.73%, and that in the control group was 50.00%, with significant statistically difference (P<0.05). The median survival time in combined therapy group (17.82±4.19 months) and control group (12.43±3.71 months) was statistically significant (P<0.05). The rate of adverse reactions of digestive tract in combined therapy group was 40.91%, which was higher than that in control group (18.18%), and the difference of two groups was statistically significant (P<0.05). The incidence of adverse reactions in blood system and bone marrow suppression in combined therapy group was 9.09% and 68.18%, which were lower than those in control group (27.27% and 95.45%), with statistically significant differences (P<0.05). There was no statistically significant difference in the incidence of liver dysfunction, cardiac insufficiency and hair loss between the two groups (P>0.05). The incidence of pulmonary infection, intestinal infection and other complications in combined therapy group was 13.64%, which was lower than that in control group 31.82%, and the difference of two groups was statistically significant (P<0.05). No serious complications such as arteriovenous thrombosis occurred in either group, and no patients died during chemotherapy. CONCLUSION: Combination of disitamine and half-course prestimulation treatmentis is a safe and effective and elderly patients with AML shown a good tolerance.


Assuntos
Decitabina/uso terapêutico , Leucemia Mieloide Aguda , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica , Azacitidina , Humanos , Leucemia Mieloide Aguda/tratamento farmacológico , Estudos Retrospectivos , Resultado do Tratamento
20.
Magn Reson Med ; 2019 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-31605554

RESUMO

PURPOSE: Without explicit coil sensitivity information acquired by means of a reference body coil, multi-channel signal combination for water-fat separation (WFS) can be challenging due to channel-dependent phase offsets and chemical-shift dependent phase shifts. This study aims to develop a referenceless, robust, accurate, and fast channel combination method for WFS. THEORY AND METHODS: A dual-step multi-channel combination method is proposed. In the first step, channel-dependent phase offsets are estimated with a preliminary WFS estimation. In the second step, the multi-channel data are combined after removing phase offsets. Thereafter, WFS is performed to obtain final results. Numerical simulations (4-64 coils) and in vivo experiments (8, 16, 28 coils) at 3T field strength are conducted to compare the proposed method to previous methods. Channel combination with a body-coil scan serves as the reference for in vivo experiments. RESULTS: The proposed method estimates channel-dependent phase offsets accurately. It shows improved robustness to phase singularities than weighted mean and adaptive reconstruction. It is faster than adaptive reconstruction (e.g., 25.45 versus 46.34 s with 28 coils) and the channel-by-channel WFS method (e.g., 21.77 versus 50.04 s with 8 coils). It provides comparable fat quantification accuracy to the reference under various reasonable signal-to-noise ratio conditions (e.g., Pearson correlation coefficient r = 0.981 with P < 0.01, for in vivo fat fractions using flip angle = 10°). CONCLUSION: The proposed referenceless channel combination method may be beneficial to both qualitative and quantitative water-fat imaging.

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