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1.
ACS Appl Mater Interfaces ; 12(1): 436-442, 2020 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-31868339

RESUMO

As a promising alternative approach to industrial N2 fixation process, electrocatalytic N2 reduction reaction (NRR) can achieve efficient, sustainable, and eco-friendly ammonia production under ambient conditions. Developing efficient NRR catalysts is critical for the electrochemical ammonia synthesis. Herein, self-supported mesoporous Au3Pd film on Ni foam (mAu3Pd/NF) has been in situ synthesized via a micelle-assisted replacement strategy. Combination of bimetallic compositions, interconnected mesoporous structure, and binder-free characteristic, the mAu3Pd/NF shows a superior NRR performance in 0.1 M Na2SO4. This micelle-assisted replacement route is very important to construct efficient self-supporting mesoporous films for the NRR and other fields.

2.
Cell Mol Life Sci ; 2019 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-31838573

RESUMO

The elevated expression of immune checkpoints by the tumor microenvironment is associated with poor prognosis in several cancers due to the exhaustion of tumor-infiltrating lymphocytes (TILs), and the effective suppression of the expression of these genes is key to reversing the exhaustion of TILs. Herein, we determined that serine/arginine-rich splicing factor 2 (SRSF2) is a target for blocking the tumor microenvironment-associated immunosuppressive effects. We found that the expression of SRSF2 was increased in exhausted T cells and that SRSF2 was involved in multiple immune checkpoint molecules mediating TILs' exhaustion. Furthermore, SRSF2 was revealed to regulate the transcription of these immune checkpoint genes by associating with an acyl-transferases P300/CBP complex and altering the H3K27Ac level near these genes, thereafter influencing the recruitment of signal transducer and activator of transcription 3 (STAT3) to these gene promoters. Collectively, our data indicated that SRSF2 functions as a modulator of the anti-tumor response of T cells and may be a therapeutic target for reversing the exhaustion of TILs.

3.
Org Lett ; 2019 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-31829020

RESUMO

We developed an electrochemically enabled dehydrogenative annulation reaction of amides and alkynes for the synthesis of antitumor polycyclic isoquinolinones through a double C-H activation route. No external oxidant is required in this reaction, and electricity is used for Ru catalyst circulation. The most remarkable feature of this reaction is the effective improvement of product regioselectivity under mild electrolytic conditions in comparison with previously set strong oxidant conditions.

4.
Phys Rev Lett ; 123(21): 217004, 2019 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-31809171

RESUMO

The interplay between unconventional Cooper pairing and quantum states associated with atomic scale defects is a frontier of research with many open questions. So far, only a few of the high-temperature superconductors allow this intricate physics to be studied in a widely tunable way. We use scanning tunneling microscopy to image the electronic impact of Co atoms on the ground state of the LiFe_{1-x}Co_{x}As system. We observe that impurities progressively suppress the global superconducting gap and introduce low energy states near the gap edge, with the superconductivity remaining in the strong-coupling limit. Unexpectedly, the fully opened gap evolves into a nodal state before the Cooper pair coherence is fully destroyed. Our systematic theoretical analysis shows that these new observations can be quantitatively understood by the nonmagnetic Born-limit scattering effect in an s±-wave superconductor, unveiling the driving force of the superconductor to metal quantum phase transition.

5.
PLoS Biol ; 17(12): e3000525, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31841517

RESUMO

Ubiquitin-specific protease (USP) 6 is a hominoid deubiquitinating enzyme previously implicated in intellectual disability and autism spectrum disorder. Although these findings link USP6 to higher brain function, potential roles for USP6 in cognition have not been investigated. Here, we report that USP6 is highly expressed in induced human neurons and that neuron-specific expression of USP6 enhances learning and memory in a transgenic mouse model. Similarly, USP6 expression regulates N-methyl-D-aspartate-type glutamate receptor (NMDAR)-dependent long-term potentiation and long-term depression in USP6 transgenic mouse hippocampi. Proteomic characterization of transgenic USP6 mouse cortex reveals attenuated NMDAR ubiquitination, with concomitant elevation in NMDAR expression, stability, and cell surface distribution with USP6 overexpression. USP6 positively modulates GluN1 expression in transfected cells, and USP6 down-regulation impedes focal GluN1 distribution at postsynaptic densities and impairs synaptic function in neurons derived from human embryonic stem cells. Together, these results indicate that USP6 enhances NMDAR stability to promote synaptic function and cognition.

6.
Org Lett ; 2019 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-31886680

RESUMO

C-centered radical cyclization under electrochemical conditions is a feasible strategy for constructing cyclic structures. Reported herein is the electrochemical synthesis of highly functionalized 1-naphthols using alkynes and 1,3-dicarbonyl compounds by (4 + 2) annulation of C-centered radical. Electrolysis was conducted with Cp2Fe as redox catalyst, thereby eliminating the use of oxidants and transition-metal catalysts. The synthesized 1-naphthol compounds showed good antitumor activity in vitro, and further studies indicated that compound 3bl induced tumor cell apoptosis.

7.
Chemistry ; 2019 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-31867812

RESUMO

Controlling the composition and morphology of Pd-based electrocatalysts is a promising strategy to develop efficient direct formic acid fuel cells. Herein, we present a two-step method to design B-doped PdCuAu nanospine assemblies (B-PdCuAu NAs) using NaBH4 as the boron dopant. The boron content can be easily tailored by tuning the reaction time, and optimal boron content is beneficial to promote the formic acid oxidation reaction. Such B-PdCuAu NAs exhibit superior mass and specific activities to those of commercial Pd black and PdCuAu NAs in alkaline solution. The excellent catalytic performance of B-PdCuAu NAs may arise from the increase in surface active sites and the electronic effect of boron modification. This work provides facile synthesis of the B-doped metallic catalysts and highlights the boron modification in improving performance as anode electrocatalysts for fuel cells.

8.
Mol Ther Nucleic Acids ; 18: 518-532, 2019 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-31671345

RESUMO

Long non-coding RNAs (lncRNAs) have been shown to be crucial regulators in numerous human diseases. However, little is known about their effects on early recurrent miscarriage (RM). Here we aimed to investigate the role of lncRNA EPB41L4A-AS1 on placental trophoblast cell metabolic reprogramming, which might be involved in the pathogenesis of RM. After microarray and GEO database analyses, we found that EPB41L4A-AS1 was significantly increased in early RM placental tissue, and this increase may relate to estradiol-mediated upregulation of PGC-1α. EPB41L4A-AS1 overexpression inhibits glycolysis but increases the dependence on fatty acid oxidation in mitochondrion metabolism and suppresses the Warburg effect, which is necessary for rapid growth of the placental villus, leading to miscarriage. Mechanistic analyses demonstrated that EPB41L4A-AS1 functions as a lncRNA in the regulation of VDAC1 and HIF-1α expression through enhancement of H3K4me3 levels in the promoters of VDAC1 and HIF1A-AS1, a natural antisense transcript (NAT) lncRNA of HIF-1α. Taken together, these findings demonstrate that aberrant expression of EPB41L4A-AS1 is involved in the etiology of early RM, and it may be a candidate diagnostic hallmark and a potential therapeutic target for early RM treatment.

9.
Chem Commun (Camb) ; 55(98): 14745-14748, 2019 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-31754678

RESUMO

In this communication, we develop a simple one-step method to prepare boron doped silver nanosponges (B-Ag NSs) with a boron content of 15 at%. Benefiting from their interconnected porous structures and composition effect, the B-Ag NSs achieve excellent NRR performance and stability. The proposed synthetic strategy provides promising insight into the preparation of boron doped metallic nanomaterials for electrocatalytic fields.

10.
Opt Express ; 27(22): 32508-32522, 2019 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-31684462

RESUMO

To reduce the reconstruction error of holographic stereogram fabricated by effective perspective images' segmentation and mosaicking method (EPISM), a multiple-reference-plane (MRP) approach is proposed and validated. The reconstruction error for traditional EPISM is analyzed, and the results indicate that the distortion as well as the blur will be involved for object points located far away from the reference plane. A new method by introducing multiple reference planes is proposed, which divides the 3D scene into several parts along its depth direction, and sets a reference plane for each of the object part. By resynthesizing all the effectively synthetic perspective images referred to their own reference planes of the object parts, the finally effectively synthetic perspective image exposed to one holographic elemental by only once exposure is generated. The optically experimental results demonstrate the validity of the proposed method, and the reconstruction error of full-parallax holographic stereogram printed by MRP based EPISM can be reduced evidently while the displayed depth range of 3D scene can be extended, compared to the traditional EPISM approach.

11.
Ann Surg ; 2019 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-31599809

RESUMO

OBJECTIVE: The aim of this study was to compare stage II/III rectal cancers with or without high-risk factors, and evaluate the effect of neoadjuvant radiotherapy (NRT) in these 2 cohorts. BACKGROUND: NRT is often used in stage II/III rectal cancers to improve local control, while not affecting overall survival. However, good-quality surgery without NRT may also achieve good local control in selected patients. METHODS: According to risk-stratification criteria and clinical staging, consecutive eligible participants of stage II/III rectal cancer were preoperatively classified into patients with (high-risk) or without (low-risk) high-risk factors. Both groups were respectively randomized to receive either short-course radiotherapy (SCRT) + total mesorectal excision (TME) or TME alone, forming the following 4 groups: high-risk patients with (HiR) or without (HiS) radiation, and low-risk patients with (LoR) or without (LoS) radiation. The primary endpoint was local recurrence. The secondary endpoints included overall survival, disease-free survival, distant recurrence, quality of surgery, and safety (NCT01437514). RESULTS: In total, 401 patients were analyzed. With a median 54 months' follow-up, low-risk patients obtained better 3-year cumulative incidence of local recurrence (2.2% vs 11.0%, P = 0.006), overall survival rate (86.9%vs 76.5%, P = 0.002), disease-free survival rate (87.0% vs 67.9%, P < 0.001), and cumulative incidence of distant recurrence (12.5% vs 29.4%, P < 0.001) than high-risk patients. With regard to 3-year cumulative incidence of local recurrence, no differences were observed between the LoR and LoS groups (1.2% vs 3.0%, P = 0.983) or the HiR and HiS groups (12.9% vs 8.9%, P = 0.483). CONCLUSIONS AND RELEVANCE: Stratification of stage II/III rectal cancers according to risk factors to more precise subclassifications may result in noteworthy differences in survivals and local pelvic control. An extremely low cumulative incidence of local recurrence and survivals in low-risk patients can be achieved with upfront good quality of surgery alone. This trial, owing to the insufficient power, could not prove the noninferiority of surgery alone, but suggest a discriminative use of NRT according to clinical risk stratification in stage II/III rectal cancer.

12.
Chemistry ; 2019 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-31599996

RESUMO

The realization of water electrolysis on the basis of highly active, cost-effective electrocatalysts is significant yet challenging for achieving sustainable hydrogen production from water. Herein, N-doped Ni3 S2 /N-doped MoS2 1D hetero-nanowires supported by Ni foam (N-Ni3 S2 /N-MoS2 /NF) are readily synthesized through a chemical transformation strategy by using NiMoO4 nanowire array growth on Ni foam (NiMoO4 /NF) as the starting material. With the in situ generation of Ni3 S2 /MoS2 heterointerfaces within nanowires and the incorporation of N- anions, an extraordinary hydrophilic nature with abundant, well-exposed active sites and optimal reaction dynamics for both oxidation and reduction of water are obtained. Attributed to these properties, as-converted N-Ni3 S2 /N-MoS2 /NF exhibits highly efficient electrocatalytic activities for both hydrogen and oxygen evolution reactions under alkaline conditions. The superior bifunctional properties of N-Ni3 S2 /N-MoS2 /NF enable it to effectively catalyze the overall water-splitting reaction.

13.
ANZ J Surg ; 89(11): E492-E497, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31566296

RESUMO

BACKGROUND: This study aimed to evaluate the technical feasibility, safety and oncological outcomes of laparoscopic total mesorectal excision (TME) with selective lateral lymph node (LLN) dissection (sLLND) in patients with locally advanced rectal cancer (LARC) and clinically suspected swollen LLNs treated with preoperative neoadjuvant chemoradiotherapy (nCRT). METHODS: Consecutive patients with LARC and swollen LLNs who underwent laparoscopic TME and sLLND following nCRT between October 2012 and October 2018 were reviewed from the prospectively collected database. Patient demographics, operation safety, perioperative complications and oncological outcomes were analysed. RESULTS: A total of 43 patients were identified. All procedures were completed under laparoscopy without conversion to open surgery. The median operation time was 313 min (range 170-570 min). The median blood loss was 80 mL (range 30-450 mL). The median number of LLNs harvested was 11 (range 1-29). LLN metastasis was found in 12 patients (27.9%). Major post-operative complications were found in four patients (9.3%). The median hospital stay was 7 days (range 4-27 days). The median time to tolerance to liquid food was 72 h (range 36-120 h). The post-operative 30-day mortality rate was 0%. Over the median follow-up of 24 months, no lateral pelvic recurrence developed. For the whole group of patients, the 2-year cumulative overall survival and disease-free survival were 90.5% and 78.1%, respectively. CONCLUSION: With the advantages of a minimally invasive approach, laparoscopic TME and sLLND following preoperative nCRT in patients with LARC and swollen LLNs is safe and feasible. This procedure provides acceptable perioperative and oncological outcomes.

14.
Chem Asian J ; 14(19): 3397-3403, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31478342

RESUMO

Pt-based nanomaterials play important roles in the catalytic process toward oxygen reduction reaction (ORR). Rationally regulating the composition and morphology of the catalysts could enhance the catalytic performance effectively. In this work, an effective method is presented to synthesize Pd@ mesoporous PtRu nanorattles (Pd@mPtRu NRs) containing a Pd core and a mesoporous PtRu shell. Owing to the unique structure and PtRu alloy composition, the prepared Pd@mPtRu NRs exhibit an enhanced catalytic performance and durability toward ORR relative to mesoporous PtRu hollow nanoparticles (mPtRu HNs) and commercial Pt/C. The proposed approach may provide a general way to synthesize Pt-based yolk-shell structures with different compositions.

15.
Chem Asian J ; 14(21): 3868-3874, 2019 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-31490629

RESUMO

Designing and constructing nano-architectures with abundant reactive atoms exposed on the surface and widely open pore interiors is an effective strategy for highly efficient utilization of Pt-based catalysts. Herein, we report a facile method to synthesize tri-metallic PtPdIr mesoporous hollow nanospheres (PtPdIr MHNSs) by selective chemical removal of sacrificial metallic cores from pre-constructed Pd@PtIr mesoporous nanospheres (Pd@PtIr MNSs). The unique nano-architectures, with mesoporous shells interconnected into the interior hollow cavities and the synergistic electronic effect from tri-metallic PtPdIr composition, enable the as-synthesized PtPdIr MHNSs to be efficient bifunctional electrocatalysts for catalyzing both methanol oxidation reaction (MOR) and oxygen reduction reaction (ORR).

16.
J Laparoendosc Adv Surg Tech A ; 29(11): 1462-1468, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31539301

RESUMO

Background: To clarify the definite incidence of isolated tumor cells (ITCs) in lateral lymph nodes (LLNs) and its prognostic significance in rectal cancer patients after laparoscopic lateral lymph node dissection (lap-LLND). Methods: Consecutive rectal cancer patients who underwent standard total mesorectal excision (TME) and lap-LLND were included. All the LLNs were re-examined by hematoxylin and eosin (H&E) stain and immunohistochemistry (IHC) with a monoclonal antibody against cytokeratin 20 to confirm the status of ITCs, micrometastasis, and overt metastasis. Clinicopathological characteristics and oncological outcomes were analyzed. Results: Forty-six patients with TME and lap-LLND were included. Twelve (26.1%) patients with overt metastasis were identified. A total of 705 LLNs from 46 patients were re-examined by H&E with IHC, and ITCs were detected in 27 (3.8%) lymph nodes from 11 (23.9%) patients. No LLNs micrometastasis was found. Patients with overt metastasis had more advanced N stage and more perirectal lymph nodes metastasis. Three patients with LLNs recurrence were identified and lung metastasis was the most common metastatic site. Compared with patients with ITCs and without any metastasis, patients with overt metastasis had worse 3-year cumulative overall survival (85.7%, 83.9%, and 53.3%, respectively) and 3-year cumulative disease-free survival (85.7%, 85.2%, and 43.8%, respectively). Patients with ITCs had higher overall recurrence than patients without any metastasis (42.9% versus 11.5%, P = .035). Multivariate analysis showed that ITC status in LLNs was a significant prognostic factor (hazard ratio 2.689, 95% confidence interval 1.072-6.747; P = .035). Conclusion: ITCs in LLNs detected by the IHC method like overt metastasis detected by H&E staining contributed to higher overall recurrence.

17.
Nanotechnology ; 30(47): 475602, 2019 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-31426034

RESUMO

The fabrication of nanorattles with controllable compositions and structures is very important for catalytic applications. Herein, we propose a facile method for synthesis of very unique all-metallic nanorattle consisting of a Pt core and a mesoporous PtPd shell (named Pt@mPtPd). Owing to its spatially and locally separated active inner Pt core and mesoporous PtPd shell, the Pt@mPtPd nanorattle shows the enhanced performance for oxygen reduction reaction. The newly designed Pt@mPtPd nanorattle is quite different from traditional nanorattles with porous carbon and silica shell in its catalytically functional mesoporous metallic shell. The proposed facile method is highly valuable for the design of all-metallic nanorattle with controllable compositions and desired functions.

18.
Sci Rep ; 9(1): 12523, 2019 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-31467313

RESUMO

The purpose of this study was to evaluate the prognostic significance of the magnetic resonance imaging-detected extramural venous invasion (MR-EMVI), the depth of mesorectal extension (MR-DME), and lymph node status (MR-LN) in clinical T3 mid-low rectal cancer. One hundred and forty-six patients with clinical T3 mid-low rectal cancer underwent curative surgery were identified. Pretreatment high-resolution MRI was independently reviewed by two experienced radiologists to evaluate MR-EMVI score (0-4), MR-DME (≤4 mm or >4 mm), and MR-LN (positive or negative). The Cox-multivariate regression analysis revealed that the MR-EMVI was the only independent prognostic factor that correlated with overall 3-year disease-free survival (DFS) (p = 0.01). The survival analysis showed that patients with positive MR-EMVI, MR-DME > 4 mm, and positive MR-LN had a poorer prognosis in the overall 3-year DFS (HR 3.557, 95% CI 2.028 to 13.32, p < 0.01; HR 3.744, 95% CI:1.165 to 5.992, p = 0.002; HR 2.946, 95% CI: 1.386 to 6.699, p < 0.01). By combining MR-EMVI with MR-DME or MR-LN, the prognostic significance was more remarkable. Our study suggested that the MR-EMVI, MR-DME, and MR-LN were the important prognostic factors for patients with clinical T3 mid-low rectal cancer and the MR-EMVI was an independent prognostic factor.

19.
Nanotechnology ; 30(48): 485403, 2019 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-31434060

RESUMO

Engineering of multicomponent heterostructures can yield exceptional functionalities and enhance electrocatalytic activities by a synergistic effect. Herein, Ni5P2 nanoparticle-decorated mesoporous PtRu film on Ni foam (Ni5P2-mPtRu/NF) has been synthesized via a facile two-step strategy. Ni5P2-mPtRu/NF possesses a well-developed continuous mesoporous structure and strong electronic interaction between Ni5P2 and PtRu, exhibiting an enhanced electrocatalytic performance towards an alkaline hydrogen evolution reaction (HER). Ni5P2-mPtRu/NF achieves a current density of 10 mA cm-2 at an overpotential of 28.8 mV and a low Tafel slope of 56.5 mV dec-1, and has excellent durability. This work provides a promising pathway for developing self-supported mesoporous multicomponent heterostructures as efficient electrocatalysts for an alkaline HER.

20.
Eur J Gastroenterol Hepatol ; 31(12): 1489-1495, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31441800

RESUMO

BACKGROUND: Synchronous colorectal carcinoma (CRC) is a specific and rare type of colorectal malignancy. The data on the impact of synchronous CRC are controversial. This study aimed to compare the characteristics and prognosis between synchronous CRC and solitary CRC. PATIENTS AND METHODS: 252 patients who underwent surgery between October 2009 and June 2013 with synchronous CRC (n = 126) or solitary CRC (n = 126) were included. The patients were matched according to age, sex, American Society of Anesthesiologists score, BMI, cancer grade, tumor location, and tumor stage. The short-term outcomes included the length of hospital stay, complications, and 30-day mortality. Long-term endpoints were overall survival (OS), disease-free survival (DFS), and cancer-specific survival (CSS). RESULTS: The median follow-up duration for all patients were 42.5 months. The incidence of synchronous CRC was high than in older and male patients as well as in mucinous adenocarcinoma containing signet-ring cell carcinoma, tumor deposit, and polypus. The length of hospital stay after surgery was longer for synchronous CRC than solitary CRC (median: 10 vs. 4 days, P = 0.033). In multivariate analysis, synchronous CRC was an independent prognostic factor associated with poor OS (hazard ratio: 2.355, 95% confidence interval: 1.322-4.195, P = 0.004), DFS (hazard ratio: 2.079, 95% confidence interval: 1.261-3.429, P = 0.004), and CSS (hazard ratio: 2.429, 95% confidence interval: 1.313-4.493, P = 0.005). CONCLUSION: The clinical and pathological features exhibit differences between synchronous CRC and solitary CRC and the prognosis of patients with synchronous CRC was poorer than those with solitary CRC.

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