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1.
Neural Regen Res ; 16(11): 2310-2315, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33818517

RESUMO

In our previous study, we showed that with increasing time in culture, the growth characteristics of enteric neural crest-derived cells (ENCCs) change, and that the proliferation, migration and neural differentiation potential of these cells in vitro notably diminish. However, there are no studies on the developmental differences in these characteristics between fetal and early-postnatal stages in vitro or in vivo. In this study, we isolated fetal (embryonic day 14.5) and postnatal (postnatal day 2) ENCCs from the intestines of rats. Fetal ENCCs had greater maximum cross-sectional area of the neurospheres, stronger migration ability, and reduced apoptosis, compared with postnatal ENCCs. However, fetal and postnatal ENCCs had a similar differentiation ability. Fetal and postnatal ENCCs both survived after transplant into a rat model of Hirschsprung's disease. In these rats with Hirschsprung's disease, the number of ganglionic cells in the myenteric plexus was higher and the distal intestinal pressure change was greater in animals treated with fetal ENCCs compared with those treated with postnatal ENCCs. These findings suggest that, compared with postnatal ENCCs, fetal ENCCs exhibit higher survival and proliferation and migration abilities, and are therefore a more appropriate seed cell for the treatment of Hirschsprung's disease. This study was approved by the Animal Ethics Committee of the Second Affiliated Hospital of Xi'an Jiaotong University (approval No. 2016086) on March 3, 2016.

2.
Int J Pharm ; : 120591, 2021 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-33845152

RESUMO

Stimuli-responsive drug delivery systems have attracted widespread attention in recent years since they can control drug release in a spatiotemporal manner and can achieve tunable drug release according to patient's physiological or pathological condition. In this review, we briefly introduce the drug delivery barriers and drug delivery systems in the anterior and posterior segment of eyes, and collect the recent advances in stimuli-responsive drug delivery systems in eyes for controlled drug release in response to exogenous stimuli (ultrasound, magnetic stimulus, electrical stimulus, and light) or endogenous stimuli (enzyme, active oxygen species, temperature, ions, and pH). in both anterior and posterior segment of eyes. In addition, the design and mechanisms of the stimuli-responsive drug delivery systems have been summarized in this review, and the advantages and limitations of these stimuli-responsive drug delivery systems are also briefly discussed.

3.
J Clin Sleep Med ; 2021 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-33843580

RESUMO

STUDY OBJECTIVES: The aim of the study was to inspect acoustic properties and sleep characteristics of pre-apneic snoring sound. The feasibility of forecasting upcoming respiratory events by snoring sound was also investigated. METHODS: Participants with habitual snoring or heavy breathing sound during sleep were recruited consecutively. Polysomnography was conducted and snoring related breathing sound was recorded simultaneously. Acoustic features and sleep features were extracted from 30-second samples and a machine learning algorithm was used to establish two prediction models. RESULTS: A total of 74 eligible participants were included. Model 1 tested by five-fold cross validation achieved the accuracy of 0.92 and area under the curve of 0.94 for respiratory event prediction. model 2 with acoustic features and sleep information tested by Leave-One-Out cross validation had the accuracy of 0.78 and area under the curve of 0.80. Sleep position was found to be the most important amongst all sleep features contributing to the performance. CONCLUSIONS: Pre-apneic sound presented unique acoustic characteristics and snoring related breathing sound could be deployed as a real-time apneic event predictor. The model combined with sleep information served as a promising tool for an early warning system to forecast apneic events.

4.
Curr Pharm Des ; 2021 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-33823762

RESUMO

BACKGROUND: Long non-coding RNAs (lncRNA) have been identified as novel molecular regulators in cancers. LncRNA ADAMTS9-AS2 can mediate the occurrence and development of cancer through various ways such as regulating miRNAs, activating the classical signaling pathways in cancer, and so on, which have been studied by many scholars. In this review, we summarize the molecular mechanisms of ADAMTS9-AS2 in different human cancers. METHODS: Through a systematic search of PubMed, lncRNA ADAMTS9-AS2 mediated molecular mechanisms in cancer are summarized inductively. RESULTS: ADAMTS9-AS2 aberrantly expression in different cancers is closely related to cancer proliferation, invasion, migration, inhibition of apoptosis. The involvement of ADAMTS9-AS2 in DNA methylation, mediating PI3K / Akt / mTOR signaling pathways, regulating miRNAs and proteins, and such shows its significant potential as a therapeutic cancer target. CONCLUSION: LncRNA ADAMTS9-AS2 can become a promising biomolecular marker and a therapeutic target for human cancer.

5.
Rapid Commun Mass Spectrom ; : e9099, 2021 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-33837602

RESUMO

RATIONALE: Gas Chromatography Mass Spectrometry (GC-MS) with electron ionization (EI)is the most widely used analysis technique of gaseous samples, but it may be time-consuming for on-line monitoring of mixtures whose concentrations relatively change rapidly. On the other hand, current ionization methods, such as chemical ionization (CI) and proton transfer reaction (PTR), also have some disadvantages such as selectivity. Appropriate soft ionization sources therefore are searched for rapid on-line detection. METHODS: Hollow Electrode Capillary Plasma Ionization (HECPI) is based on single electrode plasma. A hollow capillary was placed as both the electrode and the inlet of the gaseous samples. The ionization source is coupled with a mass spectrometer for performance evaluation. RESULTS: Several typical compounds have been tested with HECPI-mass spectrometer. In this process, the dominant ion peaks of all compounds can be indexed as molecular ion peaks, and the product ions of HECPI are less than that of dielectric barrier discharge ionization (DBDI). Three gaseous samples (linalool, triethylamine and styrene) with various concentrations have been employed to further confirm the performance of this source, and the detection limit of linalool is as low as 10 ppb. CONCLUSIONS: HECPI is simple in structure and shows good performance. The results also show that HECPI has the potential to be an effective tool for detecting on-line gaseous samples rapidly.

6.
J Cell Mol Med ; 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33797188

RESUMO

Bladder cancer (BLCA) is one of the most common urological cancer with increasing cases and deaths every year. In the present study, we aim to construct an immune-related prognostic lncRNA signature (IRPLS) in bladder cancer (BLCA) patients and explore its immunogenomic implications in pan-cancers. First, the immune-related differentially expressed lncRNAs (IRDELs) were identified by 'limma' R package and the score of IRPLS in every patient were evaluated by Cox regression. The dysregulation of IRDELs expression between cancer and para-cancer normal tissues was validated through RT-qPCR. Then, we further explore the biological functions of a novel lncRNA from IRPLS, RP11-89 in BLCA using CCK8 assay, Transwell assay and Apoptosis analysis, which indicated that RP11-89 was able to promote cell proliferation and invasive capacity while inhibits cell apoptosis in BLCA. In addition, we performed bioinformatic methods and RIP to investigate and validate the RP11-89/miR-27a-3p/PPARγ pathway in order to explore the mechanism. Next, CIBERSORT and ESTIMATE algorithm were used to evaluate abundance of tumour-infiltrating immune cells and scores of tumour environment elements in BLCA with different level of IRPLS risk scores. Finally, multiple bioinformatic methods were performed to show us the immune landscape of these four lncRNAs for pan-cancers. In conclusion, this study first constructed an immune-related prognostic lncRNA signature, which consists of RP11-89, PSORS1C3, LINC02672 and MIR100HG and might shed lights on novel targets for individualized immunotherapy for BLCA patients.

7.
Pharmaceutics ; 13(3)2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33804279

RESUMO

Proton pump inhibitors (PPIs) are the mainstay for treatment of acid-related diseases. This study developed a mechanism-based pharmacokinetic (PK) and pharmacodynamics (PD) model with ilaprazole as case drug, so as to support and accelerate the development of novel PPIs. The model was established and verified using the PK and PD data from 26 subjects receiving 5 to 30 mg of ilaprazole and 22 subjects receiving the loading dose of ilaprazole 20 mg followed by 10 mg once daily for 2 days. The nonlinear mixed-effects modeling approach was performed for the PK/PD model. A two-compartment model with linear elimination and covariates (body weight and gender) described the observed data well. The relationship between plasma concentrations of ilaprazole and gastric acid pH was well quantified with individual variability, in which the synthesis and degradation of H+/K+-ATPase, the food effect, the circular rhythms of gastric acid secretion, and the irreversible inhibition of H+/K+-ATPase by ilaprazole were integrated. This PK/PD model well predicted the PK and PD profile of ilaprazole in healthy subjects and patients with duodenal ulcers receiving wide range dose regimens. The mechanism-based PK/PD model provided a potential strategy to accelerate the development of novel PPIs by waiving the unnecessary clinical trials.

8.
Biol Pharm Bull ; 44(4): 507-514, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33790102

RESUMO

Preeclampsia (PE) is a severe pregnancy-specific complication responsible for a majority of maternal and fetal mortality. The dysfunction of trophoblast cells is known to be associated with the etiology of PE. Moreover, elevated expression of hsa_circ_0001326 was found in patients with PE without elucidating specific mechanisms. Thus, this study aimed to investigate the role of hsa_circ_0001326 in the dysfunction of trophoblast cells in vitro. Human trophoblast SWAN71 cells were used in this study. Cell proliferation, apoptosis and cell cycle were detected by 5-ethynyl-2'-deoxyuridine (EdU) staining, cell counting kit-8 assay, Annexin V/propidium iodide (PI) staining and flow cytometry, respectively. Dual luciferase assay was performed to validate the predicted targets. Additionally, Western blot was conducted for protein detection. The results indicated overexpression (OE) of hsa_circ_0001326 remarkably decreased the viability and proliferation of SWAN71 cells. MiR-186-5p was identified as the target of hsa_circ_0001326. Meanwhile, p27 Kip1 was validated as the target of hsa_miR-186-5p. Moreover, the increased apoptosis and decreased migration induced by hsa_circ_0001326 OE were inhibited by p27 Kip1 knockdown. Hsa_circ_0001326 OE upregulated p27 Kip1 and cleaved caspase3 and downregulated CDK2 and cyclin E1 in cells, while these phenomena were reversed by p27 Kip1 knockdown. In addition, hsa_circ_0001326 OE induced G0/G1 cell cycle arrest was also attenuated in the presence of p27 Kip1 knockdown. Taken together, hsa_circ_0001326 OE contributed to the decreased viability of SWAN71 cells by targeting miR-186-5p via upregulation of p27 Kip1. Our findings were helpful to uncover the pathophysiological process of PE, as well as inspire the development of novel targeted therapy against PE.

9.
J Immunol Res ; 2021: 6618837, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33791391

RESUMO

Mitochondrial Pyruvate Carrier 1 (MPC1), one of the rate-limiting proteins involved in glycolysis metabolism, has been demonstrated as a tumor inhibitor in several cancers. This study was conducted with the aim of exploring the role and underlying mechanisms of MPC2 in colorectal cancer (CRC). Here, we found that MPC2 expression was decreased in CRC samples. According to the analysis on our TMA data, lower expression of MPC2 is correlated with a higher incidence of distant metastasis and lymph node invasion, bigger tumor size, low survival rate of patients, and advanced T stages. Functionally, in vivo/vitro experiments showed that MPC2 knockdown induced CRC cell proliferation and growth, while MPC2 overexpression inhibited the proliferation and growth of CRC. Further study demonstrated that MPC2 knockdown resulted in aerobic glycolysis in CRC cells. Similarly, MPC2 overexpression in CRC cells also caused inhibited aerobic glycolysis. Further study found that MPC2 knockdown in CRC cell lines activated the mTOR signaling pathway, and the addition of rapamycin reversed the promoting effect of MPC2 knockdown on CRC proliferation and glycolysis. Likewise, the addition of MHY1485 also reversed the MPC2 overexpression's role in hindering aerobic glycolysis in CRC cells. Collectively, our study established that low expression of MPC2 led to CRC growth as well as aerobic glycolysis through the regulation of the mTOR pathway in CRC cells, indicating a potential biomarker and therapy target for CRC.

10.
Ocul Immunol Inflamm ; : 1-8, 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33793358

RESUMO

Purpose: to explore the aqueous cytokine profiles in nAMD patients before and after conbercept therapy.Methods: aqueous levels of 17 cytokines were detected in 20 treatment-naïve nAMD eyes and 20 age- and sex-matched age-related cataract (ARC) eyes. All of the nAMD patients received three intravitreal injections of conbercept. The central macular thickness (CMT) and maximum retinal thickness-3 mm (MRT-3 mm) were measured by SD-OCT. Fundus fluorescein angiography (FA) was used to measure the greatest linear diameter (GLD).Results: Aqueous endoglin, endostatin, FGF-α, HGF, and thrombospondin-2 levels were significantly higher in the nAMD group than those in the ARC group, whether before or after two conbercept injections. In the nAMD group, baseline thrombospondin-2 was positively correlated with GLD. Baseline FGF-α, thrombospondin-2, and VEGF-A were positively correlated with MRT-3 mm. After two conbercept injections, endostatin levels were positively correlated with VEGF-A.Conclusions: Endoglin, endostatin, FGF-α, HGF, and thrombospondin-2 may participate in the pathogenesis of nAMD.

11.
Transgenic Res ; 2021 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-33786748

RESUMO

Histamine H2 receptor (HRH2) is closely associated with the development of cardiovascular and cerebrovascular diseases. However, systematic Hrh2 knockout mice did not exactly reflect the HRH2 function in specific cell or tissue types. To better understand the physiological and pathophysiological functions of endothelial HRH2, this study constructed a targeting vector that contained loxp sites flanking the ATG start codon located in Hrh2 exon 2 upstream and a neomycin (Neo) resistance gene flanked by self-deletion anchor sites within the mouse Hrh2 allele. The targeting vector was then electroporated into C57BL/6J embryonic stem (ES) cells, and positively targeted ES cell clones were micoinjected into C57BL/6J blastocysts, which were implanted into pseudopregnant females to obtain chimeric mice. The F1 generation of Hrh2flox/+ mice was generated via crossing chimeric mice with wild-type mice to excise Neo. We also successfully generated endothelial cell-specific knockout (ECKO) mice by crossing Hrh2flox/+ mice with Cdh5-Cre mice that specifically express Cre in endothelial cells and identified that Hrh2 deletion was only observed in endothelial cells. Hrh2flox/+ and Hrh2ECKO mice were normal, healthy and fertile and did not display any obvious abnormalities. These novel animal models will create new prospects for exploring roles of HRH2 during the development and treatment of related diseases.

12.
Orthop Surg ; 2021 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-33787067

RESUMO

OBJECTIVE: The objective of the present paper was to explore the clinical effect of one approach anterior decompression and fixation with posterior unilateral pedicle screw fixation for thoracolumbar osteoporosis vertebral compression fractures (OVCF). METHODS: This is a single-center retrospective analysis. A total of six thoracolumbar OVCF patients (four women and two men) with an average age of 65.2 years (58-72 years) who were treated between June 2016 and May 2018 were enrolled in the present study. The lesion segments included: 1 case at T11, 1 case at T12, 3 cases at L1, and 1 case at L2. The six thoracolumbar OVCF patients were treated with one approach anterior decompression and fixation with posterior unilateral pedicle screw fixation. After general anesthesia, patients were placed in the right lateral decubitus position, an approximately 10-15-cm oblique incision was made along corresponding ribs, and the conventional left retroperitoneal and/or the extrapleural approach was performed for anterior lateral exposure. First, anterior decompression and fixation were performed, and then through the unilateral paraspinal muscle approach, posterior pedicle screw fixation was performed under the same incision. The back pain visual analogue scale (VAS), the Oswestry disability index (ODI), and the MacNab criteria were used to evaluate the clinical outcome. The radiographic analysis included the regional kyphosis angle and the fusion rate. Neurological status, operation time, intraoperative bleeding, the time of ambulation, hospital stay, and surgical complications were also assessed. RESULTS: Surgery was successful in all six patients, who were followed up for 31.6 months (range, 23-46 months). The operation time was 125-163 min, with a median of 135 min. The preoperative blood loss was 580-1230 mL, with a median of 760 mL. The time of ambulation was 3-5 days, with a median of 4.2 days. The hospital stay was 8-15 days, with the median of 10.5 days. According to the Frankel classification of neurological deficits, of two patients with grade C preoperatively, one had improved to grade D and one had improved to grade E at final follow up; among four patients with grade D preoperatively, at the final follow up one remained the same and three had improved to grade E. The postoperative back pain VAS score decreased significantly, from 6.17 ± 0.75 preoperatively to 0.83 ± 0.41 postoperatively (P < 0.05). The mean ODI score was 73.7 ± 5.86 preoperatively and reduced to 21.85 ± 3.27 postoperatively (P < 0.05). According to the MacNab criteria, at the final follow up, two patients rated their satisfaction as excellent, three patients as good, and one patient as fair. The mean regional kyphosis angle was 22.17° ± 6.01°before surgery, which improved to 9.33° ± 3.88° at the final follow up (P < 0.05). At the final follow up, there were two patients who had achieved a grade 2 bony fusion (33.3%), three patients grade 3 (50.0%), and one patient grade 4 (16.7%). No incision infections, internal fixation failures or other complications were found during the perioperative and the follow-up period. CONCLUSION: One approach anterior decompression and fixation with posterior unilateral pedicle screw fixation provides a novel method for thoracolumbar OVCF disease, with a satisfactory clinical outcome.

13.
Pharmacol Res ; 167: 105572, 2021 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-33753246

RESUMO

Metabolic diseases are becoming increasingly common in modern society. Therefore, it is essential to develop effective drugs or new treatments for metabolic diseases. As an active ingredient derived from plants, celastrol has shown great potential in the treatment of a wide variety of metabolic diseases and received considerable attention in recent years. In reported studies, the anti-obesity effect of celastrol resulted from regulating leptin sensitivity, energy metabolism, inflammation, lipid metabolism and even gut microbiota. Celastrol reversed insulin resistance via multiple routes to protect against type 2 diabetes. Celastrol also showed effects on atherosclerosis, cholestasis and osteoporosis. Celastrol in treating metabolic diseases seem to be versatile and the targets or pathways were diverse. Here, we systematically review the mechanism of action, and the therapeutic properties of celastrol in various metabolic diseases and complications. Based on this review, potential research strategies might contribute to the celastrol's clinical application in the future.

14.
Artigo em Inglês | MEDLINE | ID: mdl-33779904

RESUMO

The pumping performance of the traditional vertical well is often poor in municipal solid waste (MSW) landfills due to the blocking effect of landfill gas on leachate migration. To improve the pumping performance, a vacuum vertical well was designed and then installed at the Tianziling landfill. When the leachate was drawn out through submersible pump, the landfill gas was simultaneously extracted through vacuum pump to form vacuum pressure in the well. The vacuum pressure could increase the hydraulic gradient of leachate flow as well as the relative liquid permeability of MSW. Pumping tests were carried out to explore the effectiveness of the vacuum pressure on improving the pumping performance of vertical well. When the vacuum pressure increased from 0 kPa to - 30 kPa, the steady leachate pumping rate increased from 1.58 to 2.34 m3/h, and the steady leachate level drawdown increased from 5.9 to 10.3 m at the distance of 5 m. The vacuum pressure mainly affected the leachate level drawdown within the distance of 15-20 m. When the vacuum pressure in the pumping well was - 30 kPa, it attenuated to - 14.7 kPa and - 6.6 kPa at the distance of 5 m and 10 m, respectively. The influence radius of vacuum pressure was about 15 m. Numerical modeling indicates that the leachate pumping rate and drawdown will decrease with the increase in decreasing rate of hydraulic conductivity with depth, degree of heterogeneity, and anisotropy of hydraulic conductivity of waste. The experimental and numerical results demonstrate the effectiveness of vacuum pressure and provide working parameters for the application of the vacuum wells in MSW landfills.

15.
Environ Sci Technol ; 2021 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-33734680

RESUMO

Agricultural soil is the main source of nitrous oxide (N2O) emissions which contribute to global warming and stratospheric ozone depletion. In recent decades, atmospheric nitrogen (N) deposition has increased dramatically as an important agricultural soil N input, while its effect on soil N2O emissions in the current and future climate change remains unknown. Here, we conducted a thorough analysis of the effect of N deposition and climate change on soil N2O emissions as well as their trends. Soil N2O emissions induced by N deposition accounted for 25% of global cropland soil N2O emissions. Global soil N2O emissions over croplands increased by 2% yr-1 during 1996-2013, of which N deposition could explain 15% of the increase. The emission factor of N deposition was ∼7 times that of N fertilizer plus manure (∼1%) through a more direct way, since N deposition including nitrate (NO3-) and ammonium (NH4+) could be directly used for nitrification and denitrification. By 2100, N deposition will increase by 80% and cropland soil N2O emissions will increase by 241% under the RCP8.5 scenario in comparison with the 2010 baseline. These results suggest that, under the background of increasing global N deposition, it is essential to consider its effects on soil N2O emissions in climatic change studies.

16.
J Nat Prod ; 2021 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-33788569

RESUMO

The new polycyclic polyprenylated acylphloroglucinols, hyperforcinols A-J (1-10), were isolated from the fruits of Hypericum forrestii, together with 30 biogenetic congeners of known structures. The structures of hyperforcinols A-J were determined by HRESIMS and 1D/2D NMR spectroscopic analysis, and their absolute configurations were determined by a combination of the electronic circular dichroism (ECD) exciton chirality method, ECD calculations, and X-ray diffraction analysis. A selection of 25 isolates, possessing seven types of carbon skeletons, were assessed for their in vitro effects against nonalcoholic steatohepatitis (NASH) using a free fatty acid-induced L02 cell model. Compounds 20 and 40 significantly decreased intracellular lipid accumulation. QRT-PCR analyses revealed that compounds 20 and 40 regulate the expression of lipid metabolism-related genes, including CD36, FASN, PPARα, and ACOX1.

17.
Biomolecules ; 11(2)2021 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-33671480

RESUMO

The resurrection plants Myrothamnus flabellifolia can survive long term severe drought and desiccation conditions and soon recover after rewatering. However, few genes related to such excellent drought tolerance and underlying molecular mechanism have been excavated. WRKY transcription factors play critical roles in biotic and abiotic stress signaling, in which WRKY70 functions as a positive regulator in biotic stress response but a negative regulator in abiotic stress signaling in Arabidopsis and some other plant species. In the present study, the functions of a dehydration-induced MfWRKY70 of M. flabellifolia participating was investigated in the model plant Arabidopsis. Our results indicated that MfWRKY70 was localized in the nucleus and could significantly increase tolerance to drought, osmotic, and salinity stresses by promoting root growth and water retention, as well as enhancing the antioxidant enzyme system and maintaining reactive oxygen species (ROS) homeostasis and membrane-lipid stability under stressful conditions. Moreover, the expression of stress-associated genes (P5CS, NCED3 and RD29A) was positively regulated in the overexpression of MfWRKY70 Arabidopsis. We proposed that MfWRKY70 may function as a positive regulator for abiotic stress responses and can be considered as a potential gene for improvement of drought and salinity tolerance in plants.

18.
J Phys Chem Lett ; : 3006-3013, 2021 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-33733772

RESUMO

Understanding the effect of interfacial interactions between the protection motifs and gold cores on the stabilities of thiolate-protected gold nanoclusters is still a challenging task. Based on analyses of 95 experimentally crystallized and theoretically predicted thiolate-protected gold nanoclusters, we present a ring model to offer a deeper insight into the interfacial interactions for this class of nanoclusters. In the ring model, all the gold nanoclusters can be generically viewed as a fusion or interlocking of several [Aum(SR)n] (m = 4-8, 10, and 12 and 0 ≤ n ≤ m) rings. Guided by the ring model and the grand unified model, a new Au42(SR)26 isomer is predicted, whose total energy is lower than those of two previously crystallized isomers. The ring model offers a mechanistic understanding of the interactions between the protection ligands and gold cores and practical guidance on predicting new gold nanoclusters for future experimental synthesis and confirmation.

19.
J Phys Chem Lett ; 12(9): 2312-2319, 2021 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-33651620

RESUMO

To achieve efficient conversion and avoid loss of solar energy, ultrafast charge separation and slow electron-hole recombination are desired. Combining time-dependent density functional theory (TD-DFT) with nonadiabatic molecular dynamics, Au9(PH3)8/MoS2, as a prototype for zero-dimensional/two-dimensional (0D/2D) heterojunction, has been demonstrated to present excellent light absorption capacity and effective charge separation characteristics. In the heterojunction, photoexcitation of the Au9(PH3)8 nanocluster drives an ultrafast electron transfer from Au9(PH3)8 to MoS2 within 20 fs, whereas photoexcitation of the MoS2 nanosheet leads to hole transfer from MoS2 to Au9(PH3)8 within 680 fs. The strong nonadiabatic coupling and prominent density overlap are responsible for the faster electron separation relative to hole separation. In competition with the charge separation, electron-hole recombination requires 205 ns, ensuring an effective carrier separation. Our atomistic TD-DFT simulation provides valuable insights into the photocarrier dynamics at the Au9(PH3)8/MoS2 interface, which would stimulate the exploration of 0D/2D hybrid materials for photovoltaic and optoelectronic devices.

20.
Bioorg Med Chem Lett ; 41: 127993, 2021 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-33775841

RESUMO

Tranylcypromine (TCP)-based structural modifications lead to the discovery of new LSD1 inhibitors, of which compounds 26b and 29b effectively inhibit LSD1 with the IC50 values of 17 and 11 nM, respectively and also show good selectivity over MAO-B. Mechanistic studies showed that compound 29b concentration-dependently induced H3K4me1/2 accumulation in LSD1 overexpressed MGC-803 cells and also inhibited metastasis of MGC-803 cells. Collectively, both compounds could be promising lead compounds for further investigation.

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