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1.
Chemosphere ; 240: 124789, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31561157

RESUMO

Poly- and perfluorinated compounds (PFCs) may induce potential endocrine-disrupting hormonal effects. However, the molecular mechanism of the toxicology of PFCs remains unclear, and the insufficient information is available on the biological activities of PFCs at present. In this study, the cell-based reporter gene assays were used to determine the agonistic activity of PFCs on the human pregnane X receptor (hPXR). The heuristic method combined with best subset modeling (HM-BSM) based on Dragon descriptors and comparative similarity indices analysis (CoMSIA) were employed to build classical quantitative structure-activity relationship (QSAR) and three-dimensional QSAR models, respectively. The applicability domain (AD) of the classical QSAR model was assessed. Both the HM-BSM and CoMSIA approaches demonstrated good robustness, predictive ability, and mechanistic interpretability. The r2 and leave-one-out cross-validation squared correlated coefficient (q2LOO) values were 0.872 and 0.759 for the HM-BSM, and 0.976 and 0.751 for the CoMSIA model, respectively. The hPXR agonistic activity of the PFCs predicted by the built HM-BSM and CoMSIA agreed well with experimental activity, with root mean square error (RMSE) values of 0.0803 and 0.117, respectively, and external validation squared correlated coefficients (q2EXT) of 0.972 and 0.932, respectively. The hPXR agonistic activity of PFCs was related to their molecular polarizability, charge and atomic mass. Hydrogen bonding and hydrophobic interactions constituted the primary intermolecular forces between PFCs and the hPXR. The developed models were used to screen the PFCs with high hPXR agonistic activity.

2.
J Clin Anesth ; 59: 106-111, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31330457

RESUMO

STUDY OBJECTIVE: The study was to determine the analgesic effect of ultrasound-guided intercostal nerve block (ICNB) and single-injection erector spinae plane block (ESPB) in comparison with multiple-injection paravertebral block (PVB) after thoracoscopic surgery. DESIGN: Randomized, controlled, double- blinded study. SETTING: Operating room, postoperative recovery room and ward. PATIENTS: Seventy-five patients, aged 18-75 years, ASA I-II and scheduled for elective thoracoscopic partial pulmonary resection surgery were enrolled in the study. Seventy-two patients were left for final analysis. INTERVENTIONS: Patients were randomly assigned into the three groups (PVB group, ICNB group or ESPB group). After anesthesia induction, a single anesthesiologist performed PVB at T5-T7 levels or ICNB at T4-T9 levels or ESPB at T5 level under ultrasound guidance using 20 ml of 0.375% ropivacaine. Patients were connected to the patient-controlled morphine analgesia device after surgery. MEASUREMENTS: Cumulative morphine consumption at 24 h postoperatively as primary outcome was compared. Visual analog scale pain scores at rest and while coughing at 0, 2, 4, 8, 24 and 48 h postoperatively, cumulative morphine consumption at other observed time and rescue analgesia requirement were also recorded. MAIN RESULTS: There was a significant difference in median [interquartile range, IQR] morphine consumption at 24 h postoperatively among the three groups (PVB, 10.5 [9-15] mg; ICNB, 18 [13.5-22.1] mg; ESPB, 22 [15-25.1] mg; p = 0.000). This difference was statistically significant for PVB group vs ESPB group (median difference, -7.5; 95% confidence interval [CI], -12 to -4.5; p = 0.000) and PVB group vs ICNB group (median difference, -6; 95% CI, -9 to -3; p = 0.001), but not for ICNB vs ESPB (median difference, -3; 95% CI, -6 to 1.5; p = 0.192). PVB group had significantly lower VAS scores at rest and while coughing than ESPB group at 0, 2, 4, 8 h postoperatively and than ICNB group at 8 h postoperatively. There was no significant difference in the VAS scores between ICNB group and ESPB group at all time. Median VAS scores at rest and while coughing at all time were low (<4) in all groups. More rescue analgesia was needed in ESPB group during 48 postoperative hours (PVB vs ICNB vs ESPB; 13% vs 29% vs 46%; p < 0.05). CONCLUSIONS: Ultrasound-guided multiple-injection PVB provided superior analgesia to ICNB and single-injection ESPB, while ICNB and single-injection ESPB were equally effective in reducing pain after thoracoscopic surgery.

3.
J Ethnopharmacol ; 246: 112212, 2020 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-31494200

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: ANNAO tablets derive from Chinese classical prescriptions of Angong Niuhuang Pills with modified compositions, which have been singly or combined used for stoke associated neurological disorders. However the underlying mechanism is not yet well-defined, the present study investigated its anti-ischemic effects in rat middle cerebral artery occlusion (MCAO) model and focused on mitochondrial quality control. MATERIALS AND METHODS: Rats were subjected to 2 h of brain ischemia followed by 1 day or up to 7 days of reperfusion. Vehicle, ANNAO tablets or Edaravone were given at 1h after the start of reperfusion for 1 day or successive 7 days in MCAO rats. For the behavior assessment, Longa test and modified Neurological Severity Scores (m NSS) test were performed. Following the behavioral assessment, we assessed the protein expressions related to mitochondrial function. Moreover, we also assessed the neuroprotective effects of ANNAO tablets by immunohistochemical analysis. RESULTS: Compared with sham rats, ANNAO tablets improved the behavioral performance and decreased the infarction volume in the MCAO rats. Western blotting results showed that ANNAO tablets altered the expression level of multiple proteins related to mitochondrial function, elevated the ratio of Bcl-2/Bax and inhibited the apoptosis. Additionally, ANNAO tablets increased the number of NeuN positive neurons. CONCLUSIONS: The obtained data demonstrated that ANNAO tablets exhibited an obvious anti-cerebral ischemia-reperfusion effect, which could be attributed to the improvement of mitochondrial quality control.

4.
J Nanosci Nanotechnol ; 20(5): 3239-3245, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-31635670

RESUMO

Supramolecular assembly in vitro is a simple and effective way to produce multi-level biostructures to mimic the self-assembly of biomolecules in organisms. The study on peptide assembly behaviors would benefit a lot to understand what goes on in life, as well as in the construction of plenty of functional biomaterials that have potential applications in various fields. Since cellular microenvironments are crowded and contain various biomolecules, studying protein and peptide co-assembly is of great interest. Here, we introduced the co-assembly of 5-FAM-ELVFFAE-NH2 (EE-7) and (CY5)-KLVFFAK-NH2 (KK-7), which are sequences derived from the core of the amyloid ß (Aß) peptide, a key protein in Alzheimer's diseases. Morphologic studies employing atomic force microscopy and scanning electron microscopy indicated that the co-assembled entities had a novel hydrangea-like microstructure, in contrast to micro-sheet structures formed from monocomponent EE-7 or KK-7, respectively. Fluorescence co-localization experiments confirmed that the hydrangealike microstructures were indeed made of both EE-7 and KK-7. We suggest that the formation of the hydrangea-like microstructures is driven by both the electrostatic and hydrophobic interactions between EE-7 and KK-7. A molecular mechanism has been provided to explain the formation of the hydrangea-like microstructures.

5.
Bioresour Technol ; 295: 122289, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31670204

RESUMO

To enhance the biodegradability and methane production of hybrid Pennisetum, a pretreatment method with high selectivity for lignin removal, namely sodium chlorite/acetic acid (SCA) pretreatment, was examined in this work. Results showed that SCA pretreatment can selectively remove lignin with minimal impact on cellulose and hemicellulose. After up to 200 min of SCA treatment, 79.4% of lignin was removed and over 90% of the holocellulose was retained. The physicochemical changes after pretreatment were analyzed by confocal laser scanning microscopy, X-ray diffractometer and Fourier transform infrared spectroscopy, showing that the majority of lignin was removed from secondary cell walls and cell middle lamella while the chlorite-resistant lignin remained in the cell corner. Lignin removal significantly enhanced the biodegradability from 59.6% to 86.4% and increased methane production by 38.3%. Energy balance showed that SCA pretreatment was efficient to increase the energy output of hybrid Pennisetum.


Assuntos
Lignina , Pennisetum , Anaerobiose , Cloretos , Metano
6.
Food Chem ; 306: 125581, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31606636

RESUMO

A comprehensive evaluation was conducted to compare the generation of antioxidative peptides produced by alcalase versus trypsin from Atlantic sea cucumber. The in vitro antioxidative peptides were sequenced by de novo sequencing using LC-MS/MS. Key constituent antioxidative amino acids (KCAAA), i.e., Cys, His, Met, Trp and Tyr in the peptides and the molecular interactions between peptides and myeloperoxidase (MPO, a mediator and marker of in vivo oxidative stress), were analyzed by in silico methods. Alcalase-produced protein hydrolysates showed 5-35% higher in vitro antioxidant activity than the trypsin-produced ones. UPLC analysis revealed the total amino acid composition in peptide fractions <2 kDa. Alcalase produced 35.4% of peptides with both KCAAA and potential MPO inhibitory activity, compared with only 30.3% for trypsin. A representative peptide sequence TEFHLL generated by alcalase had intense molecular interactions with MPO active site, predicting a capacity to inhibit in vivo oxidative stress.

7.
Dev Comp Immunol ; 102: 103487, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31472172

RESUMO

Myelocytomatosis viral oncogene (MYC), a transcription factor in the MYC family, plays vital roles in vertebrate innate immunity by regulating related immune gene expressions. In this study, we cloned and characterized an MYC gene from sea cucumber Apostichopus japonicus via RNA-seq and RACE approaches (designated as AjMYC). A 2074 bp fragment representing the full-length cDNA of AjMYC was obtained. This gene includes an open reading frame (ORF) of 1296 bp encoding a polypeptide of 432 amino acid residues with the molecular weight of 48.85 kDa and theoretical pI of 7.22. SMART analysis indicated that AjMYC shares an MYC common HLH motif (354-406 aa) at the C-terminal. Spatial expression analysis revealed that AjMYC is constitutively expressed in all detected tissues with peak expression in the tentacle. Vibrio splendidus-challenged sea cucumber could significantly boost the expression of AjMYC transcripts by a 5.58-fold increase in the first stage. Similarly, 2.75- and 3.23-fold increases were detected in LPS-exposed coelomocytes at 1 and 24 h, respectively. In this condition, coelomocyte apoptotic rate increased from 11.98% to 56.23% at 1 h and to 59.08% at 24 h. MYC inhibitor treatment could not only inhibit the expression of AjMYC and Ajcaspase3, but also depress the coelomocyte apoptosis. Furthermore, AjMYC overexpression in EPC cells for 24 h also promoted the cell apoptosis rate from 21.31% to 45.85%. Collectively, all these results suggested that AjMYC is an important immune factor in coelomocyte apoptosis toward pathogen-challenged sea cucumber.

8.
Sci Total Environ ; 698: 134175, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31518786

RESUMO

Although jarosite and visible light are important factors for the formation of acid mine drainage (AMD), the effects of combined jarosite and visible light on chalcopyrite biodissolution have not been explored until now. In order to fill this knowledge gap, the combined effects of jarosite and visible light on chalcopyrite dissolution mediated by Acidithiobacillus ferrooxidans were investigated. The results indicated that jarosite and visible light could significantly accelerate chalcopyrite biodissolution, thus releasing more copper ions, iron ions and producing more acid. This in turn suggests enhanced generation of AMD under these conditions. Biodissolution results, mineral surface morphology, mineralogical phase and elemental composition analyses revealed that the promotion of chalcopyrite dissolution by additional jarosite and visible light was mainly attributed to the acceleration of ferric iron/ferrous iron cycling and the inhibition of the formation of a passivation layer (jarosite and Sn2-/S0) on the surface of chalcopyrite. This study provides a better understanding of the effects of jarosite and visible light on chalcopyrite biodissolution. In the future, the influences of jarosite and visible light on chalcopyrite dissolution should be considered in AMD evaluation to ensure reliability.

9.
Opt Express ; 27(22): 32649-32658, 2019 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-31684473

RESUMO

We propose and experimentally demonstrate an ytterbium-doped fiber laser emitting the single high-order cylindrical vector beams with a high efficiency and a high modal purity based on adaptive modal gain control. By the combination of a high-order pump with a self-designed ytterbium-ring doped fiber, modal dependent gain was tailored and specific transverse mode can be selected in the laser cavity. A model based on multimode propagation-rate equations is built up to demonstrate the behaviors of transverse mode competition in the fiber laser. Modal dependent gain of high-order mode pump are simulated numerically, which agree well with our experiment results. The slope efficiency of the fiber laser reaches 79.61% with a low threshold of 47.73mw. The purity of the generated high-order CVBs are in excess of 95%. Such a strategy enables the controllability of modal gain in a fiber laser and reveals the potential to offer a new and promising way to achieve a high-power fiber laser with an arbitrary single high-order transverse modes output.

10.
Opt Express ; 27(20): A1601-A1614, 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31684591

RESUMO

Optical polarization characteristics and light extraction behavior of deep-ultraviolet (DUV) light-emitting diode (LED) flip-chip with full-spatial omnidirectional reflector (FSODR) have been investigated. FSODR is fabricated to be simultaneously covered on the whole flip-chip, except the sapphire surface. It is found that the FSODR greatly enhance both transverse-electric (TE) and transverse-magnetic (TM) mode light extraction at every space angle, resulting in total enhancement of 73.1% and 79.8%, respectively. Moreover, the four individual ODR structures separated from FSODR, which are covered on the surface of n-AlGaN, the interface of p-GaN/p-AlGaN, the sidewall of mesa and the sidewall of n-AlGaN/AlN, respectively, show considerably different optical polarization characteristics and extraction behaviors between each other. The achievements of FSODR cannot be obtained by any separated ODR, and all of the individual ODRs can contribute to the FSODR. Especially, the synergy effect of TM extraction behavior obviously exists in FSODR. As a result, the light extraction efficiency (LEE) enhancement of FSODR is approximately 60% at a high current density of 140A/cm2. This study is significant for understanding and modulating the extraction behavior of polarized light to realize high efficiency AlGaN-based DUV LEDs.

11.
Molecules ; 24(22)2019 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-31717285

RESUMO

Hybrid white organic light-emitting diodes (WOLEDs) have drawn great attention both for display and solid-state lighting purposes because of the combined advantages of desirable stability of fluorescent dyes and high efficiency of phosphorescent materials. However, in most WOLEDs, obtaining high efficiency often requires complex device structures. Herein, we achieved high-efficiency hybrid WOLEDs using a simple but efficacious structure, which included a non-doped blue emissive layer (EML) to separate the exciton recombination zone from the light emission region. After optimization of the device structure, the WOLEDs showed a maximum power efficiency (PE), current efficiency (CE), and external quantum efficiency (EQE) of 82.3 lm/W, 70.0 cd/A, and 22.2%, respectively. Our results presented here provided a new option for promoting simple-structure hybrid WOLEDs with superior performance.

12.
Chemosphere ; 242: 125154, 2019 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-31675575

RESUMO

The soils in mining lands with cadmium (Cd) contamination usually are deficient in nutrients. Disclosing how P nutrition and N:P stoichiometric ratio influences Cd accumulation and stress tolerance in stems of Populus spp. will facilitate the phytoremediation of mining sites polluted by Cd. In this study, investigations at the anatomical and physiological levels were conducted using a clone of Populus × euramericana. Both phosphorus deficiency and cadmium exposure inhibited xylem development via reducing cell layers in the xylem. Under P-sufficient condition, appropriate P status and balanced N:P ratio in stem promoted xylem development under Cd exposure via stimulating cell division, which enhanced Cd accumulation in stems. Cd accumulation in cell walls of collenchyma tissues of the stem was enhanced by P application due to increased polysaccharide production and cell wall affinity for Cd. The low P concentrations (0.3-0.4 mg g-1) and imbalanced N:P ratio under P deficiency inhibited the production of APX and ascorbate-GSH cycle, which increased oxidative stress and lipid peroxidation as indicated by high MDA concentration in stem. Under P-sufficient condition, the interactions between phytohormones and antioxidants play crucial roles in the process of antioxidant defense under Cd exposure. In conclusions, appropriate P addition and balanced N:P ratio enhanced secondary xylem development and promoted cadmium accumulation and stress tolerance in Populus stems, which can benefit the phytoextraction of Cd from Cd-contaminated soil.

13.
Artigo em Inglês | MEDLINE | ID: mdl-31693945

RESUMO

Cadmium (Cd) is a nonessential metal that is a contaminant in aquatic ecosystems. Cd can accumulate in aquatic animals, leading to detrimental effects in tissues, and Cd exposure can induce immunotoxicity in fish. MicroRNAs (miRNAs) play critical roles in immune responses, yet the participation of miRNAs in Cd-induced immunotoxicity remains poorly understood. The present study evaluated the effects of Cd exposure on the immune responses and the mRNAs and miRNAs expressions of immune-related genes in Cyprinus carpio (C. carpio). Then, microRNA-155 (miR-155) was overexpressed and microRNA-181a (miR-181a) was knocked down to determine which miRNA plays a key role in the immune response to Cd. The results showed that 0.5 mg/L Cd2+ significantly decreased the activity of alkaline phosphatase (AKP) and acid phosphatase (ACP) in the kidneys of C. carpio. Cd exposure upregulated the mRNA expressions of interleukin (IL)-1ß, IL-8, nuclear factor-kappa B (NF-κB), tumour necrosis factor-α (TNF-α), and Toll-like receptor 4(TLR-4) and downregulated those of IL-10 and heme oxygenase-1 (HO-1) in C. carpio kidneys. Cd exposure also led to upregulation of miR-155 and miR-181a expressions. Furthermore, AKP and ACP activity in the kidneys was markedly changed after intraperitoneal injection of C. carpio with miR-155 agomir and miR-181a antagomir. All detected mRNA expressions were significantly decreased after injection of miR-155 agomir, and IL-10, NF-κB, TNF-α, and HO-1 mRNA expressions were markedly increased after injection of miR-181a antagomir. The results of this study demonstrate that Cd exposure can immunocompromise C. carpio by targeting HO-1 through miR-155 and miR-181a. This is the first study to reveal that Cd exposure induces immunotoxicity through miR-155 and miR-181a in the kidneys of C. carpio.

14.
J Clin Lab Anal ; : e23034, 2019 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-31713264

RESUMO

OBJECTIVE: This study aimed to explore the association of integrin α7 with clinicopathological characteristics and overall survival (OS) in clear cell renal cell carcinoma (ccRCC) patients. METHODS: 179 ccRCC patients who underwent nephrectomy were included in this retrospective study. Tumor tissue and paired adjacent tissue specimens of patients were obtained. Immunohistochemistry assay was performed to detect integrin α7 expression. OS was calculated with the median follow-up duration of 91.0 months (range: 3.0-116.0 months). RESULTS: Integrin α7 was highly expressed in tumor tissue compared to paired adjacent tissue (P < .001), and tumor integrin α7 high expression was correlated with higher pathological grade (P = .004), increased T stage (P = .017), and advanced TNM stage (P = .033). Kaplan-Meier curve showed that patients with integrin α7 high expression (mean OS = 69.8, 95%CI: 60.5-79.1 months) presented with worse OS compared to patients with integrin α7 low expression (mean OS = 101.8, 95%CI: 96.0-107.7 months; P < .001). Multivariate Cox's regression analysis further disclosed that tumor integrin α7 high expression independently predicted poor OS (P < .001). CONCLUSION: Integrin α7 is upregulated and correlates with higher pathological grade, increased T stage, and advanced TNM stage, meanwhile it also acts as a valuable prognostic factor for worse survival in ccRCC patients.

15.
Cell Mol Neurobiol ; 2019 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-31713761

RESUMO

Sevoflurane is a widely used inhalational anesthetic in pediatric medicine that has been reported to have deleterious effects on the developing brain. Strategies to mitigate these detrimental effects are lacking. Sirtuin 2 (SIRT2) is a member of nicotinamide adenine dinucleotide (NAD+)-dependent protein deacetylases involved in a wide range of pathophysiological processes. SIRT2 inhibition has emerged as a promising treatment for an array of neurological disorders. However, the direct effects of SIRT2 on anesthesia-induced damage to the immature brain are unclear. Neonatal rats were exposed to 3% sevoflurane or 30% oxygen for 2 h daily with or without SIRT2 inhibitor AK7 pretreatment from postnatal day 7 (P7) to P9. One cohort of rats were euthanized 6, 12, and/or 24 h after the last gas exposure, and brain tissues were harvested for biochemical analysis and/or immunohistochemical examination. Cognitive functions were evaluated using the open field and Morris water maze tests on P25 and P28-32, respectively. SIRT2 was significantly up-regulated in neonatal rat hippocampus at 6 and 12 h post-anesthesia. Pretreatment with SIRT2 inhibitor AK7 reversed sevoflurane-induced hippocampus-dependent cognitive impairments. Furthermore, AK7 administration mitigated sevoflurane-induced neuroinflammation and microglial activation. Concomitantly, AK7 inhibited pro-inflammatory/M1-related markers and increased anti-inflammatory/M2-related markers in microglia. AK7 might prevent sevoflurane-induced neuroinflammation by switching microglia from the M1 to M2 phenotype. Downregulation of SIRT2 may be a novel therapeutic target for alleviating anesthesia-induced developmental neurotoxicity.

16.
Cancer ; 2019 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-31714592

RESUMO

BACKGROUND: The thoracic radiotherapy (TRT) target volume for limited-stage small-cell lung cancer (SCLC) has been controversial for decades. In this report, the final results of a prospective randomized trial on the TRT target volume before and after induction chemotherapy are presented. METHODS: After 2 cycles of etoposide and cisplatin, patients arm were randomized to receive TRT to the postchemotherapy or prechemotherapy tumor volume in a study arm and a control arm. Involved-field radiotherapy was received in both arms. TRT consisted of 1.5 grays (Gy) twice daily in 30 fractions to up to a total dose of 45 Gy. Lymph node regions were contoured, and intentional and incidental radiation doses were recorded. RESULTS: The study was halted early because of slow accrual. Between 2002 and 2017, 159 and 150 patients were randomized to the study arm or the control arm, respectively; and 21.4% and 19.1% of patients, respectively, were staged using positron emission tomography/computed tomography (P = .31). With a median follow-up of 54.1 months (range, 19.9-165.0 months) in survivors, the 3-year local/regional progression-free probability was 58.2% and 65.5% in the study and control arms, respectively (P = .44), and the absolute difference was -7.3% (95% CI, -18.2%, 3.7%). In the study and control arms, the median overall survival was 21.9 months and 26.6 months, respectively, and the 5-year overall survival rate was 22.8% and 28.1%, respectively (P = .26). Grade 3 esophagitis was observed in 5.9% of patients in the study arm versus 15.5% of those in the control arm (P = .01). The isolated out-of-field failure rate was 2.6% in the study arm versus 4.1% in the control arm (P = .46), and all such failures were located in the supraclavicular fossa or contralateral hilum. The regions 7, 3P, 4L, 6, 4R, 5, and 2L received incidental radiation doses >30 Gy. CONCLUSIONS: TRT could be limited to the postchemotherapy tumor volume, and involved-field radiotherapy could be routinely applied for limited-stage SCLC.

17.
Artigo em Inglês | MEDLINE | ID: mdl-31670443

RESUMO

Substitution of A-site and/or X-site ions of ABX3 -type perovskites with organic groups can give rise to hybrid perovskites, many of which display intriguing properties beyond their parent compounds. However, this method cannot be extended effectively to hybrid antiperovskites. Now, the design of hybrid antiperovskites under the guidance of the concept of Goldschmidt's tolerance factor is presented. Spherical anions were chosen for the A and B sites and spherical organic cations for the X site, and seven hybrid antiperovskites were obtained, including (F3 (H2 O)x )(AlF6 )(H2 dabco)3 , ((Co(CN)6 )(H2 O)5 )(MF6 )(H2 dabco)3 (M=Al3+ , Cr3+ , or In3+ ), (Co(CN)6 )(MF6 )(H2 pip)3 (M=Al3+ or Cr3+ ), and (SbI6 )(AlF6 )(H2 dabco)3 . These new structures reveal that all ions at A, B, and X sites of inorganic antiperovskites can be replaced by molecular ions to form hybrid antiperovskites. This work will lead to the synthesis of a large family of hybrid antiperovskites.

18.
Nanoscale ; 11(44): 21376-21385, 2019 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-31674609

RESUMO

Quantum tunnelling (QTN) devices show a promising future for energy saving and ultrafast operation thanks to the unprecedented development of two-dimensional materials. However, the immature techniques for device fabrication hamper severely their further progress and application. To overcome such a challenge, the abundant processing technology used in semiconductor electronics is worth considering. Herein, a device prototype is fabricated based on band engineering to enable flexible control of QTN probability (TP) within a III-V semiconductor multilayer. While the initial heights of all barriers are set to obtain similar TPs under no bias, the conduction band slopes of InGaSb and AlSb barriers are modulated to a state where their TPs vary reversely under electric fields. On this basis, revealed by in situ bias electron holography, a unidirectional accumulation of electrons has been realized inside the multilayer structure. Moreover, the inevitable element segregation/diffusion during device growth plays a key role in band structure optimization, which is confirmed by strain analysis. The feasibility of the above modulation strategy is also confirmed by theoretical simulations. Our findings might provide a new perspective on the innovation of semiconductor devices and the application of QTN effect.

20.
Brain Behav ; : e01454, 2019 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-31724337

RESUMO

OBJECTIVE: This study aims to explore the curative effect of dl-3-n-butylphthalide (NBP) on patients with acute cerebral infarction (ACI) and its effects on serum lipoprotein-associated phospholipase A2 (Lp-PLA2) and hypersensitive C-reactive protein (hs-CRP) levels. METHODS: A total of 136 ACI patients treated in our hospital, who met the criteria, were selected and randomly divided into two groups: control group (n = 60, including 28 males and 32 females) and treatment group (n = 76, including 32 males and 44 females). Patients in the control group were treated with routine drug therapy, while patients in the treatment group were treated with NBP on this basis. A dose of 100 ml was administered by intravenous injection for 2 times/day, for 14 days. The curative effect was evaluated using the National Institute of Health Stroke Scale (NIHSS) and Barthel index (BI) self-care ability. The levels of the two factors in serum were measured using enzyme-linked immunosorbent assay, and the changes in levels of these two factors in serum at different time points before and after treatment were compared between the two groups. RESULTS: (a) Lp-PLA2 and hs-CRP levels in the treatment group after treatment were significantly lower than those before treatment and those in the control group after treatment (p < .05). (b) The NIHSS and BI scores in the treatment group were significantly lower after treatment than before treatment and those in the control group after treatment (p < .05). CONCLUSION: Dl-3-n-butylphthalide can improve the expression of Lp-PLA2 and hs-CRP in serum in ACI patients. Furthermore, NBP has significant efficacy in inhibiting inflammation and improving neurological symptoms.

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