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1.
Artigo em Inglês | MEDLINE | ID: mdl-32424946

RESUMO

Toroids and helices are fundamental geometrical structures in nature. Polymers can self-assemble into various nanostructures, including both toroids and helices; however, nanostructures combining toroidal and helical morphologies, i.e., helical toroids, are rarely observed. Herein, we report that a binary system containing polypeptide homopolymer and its block copolymer can hierarchically self-assemble into uniform helical nanotoroids in solution. The formation of the helical toroids is a successive two-step process. First, the homopolymers aggregate into fibrils and convolve into toroids, resembling the toroidal condensation of DNA chains. Second, the block copolymers self-assemble on the homopolymer toroids resulting in helical surface patterns. Additionally, the chirality of the surface helical patterns can be varied by the chirality of the polypeptide block copolymers.

2.
Medicine (Baltimore) ; 99(18): e20184, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32358407

RESUMO

PURPOSE: Controversy remains with using neoadjuvant chemotherapy (NAC) in patients with upper tract urothelial carcinoma (UTUC). Thus, we conducted a systematic review and meta-analysis of the peer-reviewed literature to assess the role of NAC in high-risk UTUC patients. METHODS: PubMed, EMBASE, and the Cochrane Library were the main sources of relevant studies. The search terms included: "Upper urothelial carcinoma"; "UTUC"; "Urinary tract cancer"; and "Transitional cell carcinoma" combined with "Neoadjuvant chemotherapy" and "adjuvant chemotherapy". We studied the relationship of UTUC and NAC. Overall survival, recurrent-free survival, cancer-specific survival and pathological response rate in patients treated with/without NAC before radical surgery were evaluated. RESULTS: Five trials were selected, and included 532 participants. Each of the included studies was retrospective. The combined analysis showed that when compared to controls, the pooled hazard ratios of overall survival, recurrence-free survival and cancer-specific survival were 0.47 (95% confidence interval [CI], 0.34-0.64; P < .00001); 0.50 (95% CI, 0.37-0.66; P < .00001); and 0.37 (95% CI, 0.25-0.54; P < .00001), respectively. It indicates the beneficial effects of NAC for the prognosis of survival in UTUC. Additionally, NAC was significantly associated with T-stage down-grading (T3/4 to ≤T2; OR=7.58 [4.66, 12.33]; P < .0001) and pathological lymph node status (N+ to N0; OR = 6.24 [2.57,15.15]; P < .00001). CONCLUSIONS: NAC treatment before radical nephron-ureterectomy significantly improves survival prognosis in patients with high-risk upper tract urothelial carcinoma. However, considerable prospective and randomized studies are needed to confirm this perspective.

3.
FEMS Microbiol Lett ; 2020 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-32407465

RESUMO

Ulcerative colitis (UC) is a gastrointestinal disease. The link between gut microbiota and the inflammatory response in the gut has been recently established. Restoration of gut microbiota suppresses inflammatory signaling. Kuijieling (KJL) decoction, an experimental Chinese medicine formula could ameliorate the symptom of colitis. However, the involvement of gut microbiota in its curative effect is not known. Here, we would like to assess the therapeutic effect of KJL in C57BL/6 J mouse of DSS-induced UC model. Mouse feces were collected, followed by 16S rDNA sequencing. KJL decoction improved gut microbial homeostasis and suppressed inflammation in the mouse UC model. A 5-fold cross-validation and random forest analysis identified seven signature bacterial taxa representing the DSS-mediated pathogenic condition and recovery stage upon KJL decoction treatment. Overall, the findings support the notion of KJL decoction-mediated restoration of gut microbiota as a critical step of inducing remission and alleviating UC symptoms. In the present investigation, we aimed to address the question of whether KJL decoction alleviates the UC symptoms by manipulating the gut microbial structure and function.

4.
Opt Lett ; 45(10): 2808-2811, 2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-32412472

RESUMO

We present an ultra-compact optical combiner using a waveguide and geometric phase lenses (GPL) for augmented reality displays. By sandwiching the output coupler of a planar waveguide between two flat, thin GPLs, we create two optical sub-systems with different optical powers for displaying the virtual objects and transmitting the ambient light rays, respectively. We implemented our method in a scanning-based Maxwellian display and demonstrated the augmentation of an all-in-focus Maxwellian-view image with real-world objects within a 15° field of view. Our device is light (50 g) and thin (4 mm), making it well suited for wearable applications.

5.
Biomed Pharmacother ; 127: 110212, 2020 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-32422567

RESUMO

Inflammatory bowel disease (IBD) is a chronic relapsing inflammation involving the gut system, and disequilibrium of T helper (Th) cell paradigm has been recognized as critical pathogenesis. Pycnoporus sanguineus (L.) Murrill is a species of the white-rot basidiomycetes listed as food- and cosmetic-grade microorganisms. In this study, anti-inflammatory activity of the ethanol extract from P. sanguineus (PSE) was investigated in dextran sulfate sodium (DSS)-induced experimental colitis model. PSE recovered the DSS-caused weight loss, reversed the colon shortening, and ameliorated the histopathological lesion in colon, resulting in lower disease activity index (DAI). Levels of serumal lipopolysaccharide (LPS), colonic myeloperoxidase (MPO) in the colitis-suffering mice were declined by PSE treatment. PSE also improved the mucosal integrity by enhancing the expression of tight junction and adherens junction proteins in the colon, including ZO-1, occludin, claudin-1, and E-cadherin. Besides, PSE reduced helper T cells (Th) in the colon, together with an evident decrease of several Th cell-related cytokines. Moreover, it was found that in vitro, PSE suppressed T cells and the Th subset upon Concanavalin A (ConA)-stimulation by inducing apoptosis. In summary, PSE displayed a remission on the colitis-related inflammation, which would possibly rely on the epithelial barrier restoration by suppressing Th cells via apoptosis induction, highlighting a promising potential in the treatment for IBD.

6.
Dalton Trans ; 49(17): 5662-5668, 2020 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-32286602

RESUMO

Organic-inorganic hybrids have drawn great attention for gas sensors due to their high sensitivity, good selectivity and acceptable stability at room temperature. There are two main approaches by which organic-inorganic hybrids convert gas information to electric or optical signals (vapochromism). Here, we have reported a new organic-inorganic hybrid PEA2MnBr4 for humidity detection by luminescent visible chromism. PEA2MnBr4 single crystals were grown by the solution method and determined by single-crystal X-ray diffraction. Luminescent humidity chromism was found on PEA2MnBr4 from green emission at the water-desorption state to pink emission at the water-adsorption state within 18 s at a relative humidity of 38% RH. This obviously visible chromism was further used to check the water content in toluene with a low detection limit between 0.02 and 0.05 vol%.

7.
Medicine (Baltimore) ; 99(17): e19867, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32332651

RESUMO

BACKGROUND: This systematic review aims to evaluate the effectiveness of electroacupuncture in treatment of lumbar disc herniation (LDH). METHODS: Electronic databases of all electroacupuncture for LDH will be searched at PubMed, Cochrane Library, Springer, EMBASE, China National Knowledge Infrastructure (CNKI), Wan-Fang, and Chinese Biological Medical disc, (CBM) from inception to February 29, 2020, with language restricted in Chinese and English. The primary outcome is Japanese Orthopedic Association Scores, a quantification scale for a comprehensive assessment according to patients' subjects feeling and objective function. Secondary outcomes included visual analogue scale (VAS), Oswestry dysfunction index (ODI), Pittsburgh sleep quality index (PSQI), Self-rating anxiety scale (SAS), self-depression rating scale (SDS), follow-up relapse rate. The systematic review and searches for randomized controlled trials of this therapy for LDH. The Cochrane RevMan V5.3 bias assessment tool is implemented to assess bias risk, data integration risk, meta-analysis risk, and subgroup analysis risk (if conditions are met). Mean difference (MD), standard mean deviation (SMD) and binary data will be used to represent continuous results. RESULTS: This study will provide a comprehensive review and evaluation of the available evidence for the treatment of LDH with this therapy. CONCLUSION: This study will provide new evidence to evaluate the effectiveness and side effects of electroacupuncture for LDH. Due to the data is not personalized, no formal ethical approval is required.


Assuntos
Eletroacupuntura/normas , Degeneração do Disco Intervertebral/terapia , Deslocamento do Disco Intervertebral/terapia , Protocolos Clínicos , Eletroacupuntura/métodos , Humanos , Degeneração do Disco Intervertebral/fisiopatologia , Deslocamento do Disco Intervertebral/fisiopatologia , Metanálise como Assunto , Literatura de Revisão como Assunto , Resultado do Tratamento
8.
Metabolomics ; 16(5): 53, 2020 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-32303853

RESUMO

INTRODUCTION: High quality data, based on reliable quantification and clear identification of the reported lipid species, are required for the clinical translation of human plasma lipidomic studies. OBJECTIVE: Lipid quantification can be efficiently performed on triple quadrupole (QqQ) mass spectrometers in targeted multiple reaction monitoring (MRM) mode. However, a series of issues can be encountered when aiming at unambiguous identification and accurate quantification, including (i) resolving peaks of polyunsaturated species, (ii) discriminating between plasmanyl-, plasmenyl- and odd chain species and (iii) resolving the isotopic overlap between co-eluting lipid species. METHODS: As a practical tool to improve the quality of targeted lipidomics studies, we applied a Dual MS platform by simultaneously coupling a reversed-phase liquid chromatography separation to a QqQ and a quadrupole-time of flight (Q-ToF) mass spectrometers. In one single experiment, this platform allows to correctly identify, by high-resolution MS and MS/MS, the peaks that are quantified by MRM. RESULTS: As proof of concept, we applied the platform on glycerophosphocholines (GPCs) and sphingomyelins (SMs), which are highly abundant in human plasma and play crucial roles in various physiological functions. Our results demonstrated that Dual MS could provide a higher level of confidence in the identification and quantification of GPCs and SMs in human plasma. The same approach can also be applied to improve the study of other lipid classes and expanded for the identification of novel lipid molecular species. CONCLUSIONS: This methodology might have a great potential to achieve a better specificity in the quantification of lipids by targeted lipidomics in high-throughput studies.

9.
Mol Ther Nucleic Acids ; 20: 231-241, 2020 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-32193151

RESUMO

Esophageal squamous cell carcinoma (ESCC) is a common cancer occurring in males and females worldwide. Accumulating evidence continues to highlight the crucial roles of long non-coding RNAs (lncRNAs) in the process of tumorigenesis. However, the regulatory mechanism of lncRNAs in ESCC remains unclear. The aim of this study is to elucidate the role of lncRNA Krüppel-like factor 3 antisense RNA 1 (KLF3-AS1) in ESCC by regulating miR-185-5p and KLF3. Initially, ESCC cell spheres with stem cell-like properties were prepared by suspension culture, and subsequently characterized by assessing colony formation ability and stem cell markers. LncRNA KLF3-AS1 was found to be poorly expressed in ESCC and could upregulate the expression of KLF3 by binding to miR-185-5p. lncRNA KLF3-AS1 upregulation was observed to inhibit miR-185-5p, thereby contributing to decreased expression of SOX2 and Oct4 (octamer-binding transcription factor 4). Furthermore, enhancement of lncRNA KLF3-AS1 resulted in reduced colony formation ability, cell invasion and migration, and tumor volume in vivo while promoting cell apoptosis in ESCC through downregulation of miR-185-5p. Collectively, this study indicated that lncRNA KLF3-AS1 inhibited ESCC cell invasion and migration by impairing miR-185-5p-mediated inhibition of KLF3, highlighting a promising novel potential target for ESCC treatment.

10.
BMC Neurol ; 20(1): 92, 2020 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-32169039

RESUMO

BACKGROUND: To investigate predictors of postoperative acute intracranial hemorrhage (AIH) and recurrence of chronic subdural hematoma (CSDH) after burr hole drainage. METHODS: A multicenter retrospective study of patients who underwent burr hole drainage for CSDH between January 2013 and March 2019. RESULTS: A total of 448 CSDH patients were enrolled in the study. CSDH recurrence occurred in 60 patients, with a recurrence rate of 13.4%. The mean time interval between initial burr hole drainage and recurrence was 40.8 ± 28.3 days. Postoperative AIH developed in 23 patients, with an incidence of 5.1%. The mean time interval between initial burr hole drainage and postoperative AIH was 4.7 ± 2.9 days. Bilateral hematoma, hyperdense hematoma and anticoagulant drug use were independent predictors of recurrence in the multiple logistic regression analyses. Preoperative headache was an independent risk factor of postoperative AIH in the multiple logistic regression analyses, however, intraoperative irrigation reduced the incidence of postoperative AIH. CONCLUSIONS: This study found that bilateral hematoma, hyperdense hematoma and anticoagulant drug use were independently associated with CSDH recurrence. Clinical presentation of headache was the strongest predictor of postoperative AIH, and intraoperative irrigation decreased the incidence of postoperative AIH.

11.
Eur J Med Chem ; 192: 112189, 2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-32151834

RESUMO

Based on fragment-based virtual screening and bioisoterism strategies, novel indazole and pyrazolo[3,4-b] pyridine derivatives as HDACs inhibitors were designed, synthesized and evaluated. Most of these compounds displayed good to excellent inhibitory activities against HDACs, especially compounds 15k and 15m were identified as potent inhibitors of HDAC1 (IC50 = 2.7 nM and IC50 = 3.1 nM), HDAC2 (IC50 = 4.2 nM and IC50 = 3.6 nM) and HDAC8 (IC50 = 3.6 nM and IC50 = 3.3 nM). Further anti-proliferation assays revealed that compounds 15k and 15m showed better anti-proliferative activities against HCT-116 and HeLa cells than positive control SAHA. The western blot analysis results indicated that compounds 15k and 15m noticeably up-regulated the level of acetylated α-tubulin and histone H3. In addition, the two compounds 15k and 15m could arrest cell cycle in G2/M phase and promote cell apoptosis, which was similar as the reference compound SAHA. Through the molecular docking and dynamic studies, the potent HDAC inhibitory activities mainly caused by van der Waals and electrostatic interactions with the HDACs.

12.
Opt Express ; 28(2): 1345-1356, 2020 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-32121847

RESUMO

We present a foveated rendering method to accelerate the amplitude-only computer-generated hologram (AO-CGH) calculation in a holographic near-eye 3D display. For a given target image, we compute a high-resolution foveal region and a low-resolution peripheral region with dramatically reduced pixel numbers. Our technique significantly improves the computation speed of the AO-CGH while maintaining the perceived image quality in the fovea. Moreover, to accommodate the eye gaze angle change, we develop an algorithm to laterally shift the foveal image with negligible extra computational cost. Our technique holds great promise in advancing the holographic 3D display in real-time use.

14.
IEEE Trans Cybern ; 2020 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-32071018

RESUMO

This article presents a surrogate-assisted multiswarm optimization (SAMSO) algorithm for high-dimensional computationally expensive problems. The proposed algorithm includes two swarms: the first one uses the learner phase of teaching-learning-based optimization (TLBO) to enhance exploration and the second one uses the particle swarm optimization (PSO) for faster convergence. These two swarms can learn from each other. A dynamic swarm size adjustment scheme is proposed to control the evolutionary progress. Two coordinate systems are used to generate promising positions for the PSO in order to further enhance its search efficiency on different function landscapes. Moreover, a novel prescreening criterion is proposed to select promising individuals for exact function evaluations. Several commonly used benchmark functions with their dimensions varying from 30 to 200 are adopted to evaluate the proposed algorithm. The experimental results demonstrate the superiority of the proposed algorithm over three state-of-the-art algorithms.

15.
Opt Lett ; 45(3): 772-775, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-32004308

RESUMO

In this Letter, we present a snapshot hyperspectral light field imaging system using a single camera. By integrating an unfocused light field camera with a snapshot hyperspectral imager, the image mapping spectrometer, we captured a five-dimensional (5D) ($x,y,u,v,\lambda $x,y,u,v,λ) ($x,y,$x,y, spatial coordinates; $u,v,$u,v, emittance angles; $\lambda ,$λ, wavelength) datacube in a single camera exposure. The corresponding volumetric image ($x,y,z$x,y,z) at each wavelength is then computed through a scale-depth space transform. We demonstrated the snapshot advantage of our system by imaging the spectral-volumetric scenes in real time.

16.
Lasers Med Sci ; 2020 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-32006262

RESUMO

To explore the advantages and limitations of holmium laser resection of the bladder tumor (HOLRBT) versus standard transurethral resection of the bladder tumor (TURBT) in the treatment of non-muscle-invasive bladder cancer (NMIBC), the eligible studies were selected from the following databases: PubMed, Cochrane Library, and Embase. Studies comparing HOLRBT and TURBT for patients with NMIBC were included. The outcomes of interest were time of operation, catheterization and hospitalization, rates of recurrence, and perioperative complications, including obturator nerve reflex, bladder perforation, bladder irritation, and urethral stricture. Results of all data were compared and analyzed by Review Manager 5.3. A total of 9 comparative studies were finally included for this analysis. Pooled data demonstrated that HOLRBT significantly reduced the time to catheterization and hospitalization, the rate of recurrence in 2 years of follow-up, obturator nerve reflex, bladder perforation, and bladder irritation, compared with those in TURBT, respectively. However, no significant difference found between HOLRBT and TURBT in the time of operation, rate of recurrence in 1-year follow-up, and urethral stricture. The results of this research reached that HOLRBT would be a better choice than TURBT for patients with NMIBC.

17.
Spectrochim Acta A Mol Biomol Spectrosc ; 231: 118110, 2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-32007906

RESUMO

A morpholine-functionalized pyrrole-cyanine probe was synthesized via a simple condensation reaction in high yield. This probe exhibits high selectivity toward ClO- on fluorescence and UV-vis spectra in neat aqueous solution. The strong green emission of the probe solution was quenched and the yellow color faded immediately upon the addition of ClO-. The detection limit of the probe for ClO- was 0.165 µM. The mechanism of hypochlorite-induced CC breakage was supposed on the basis of EIS-MS, NMR, and density functional theory (DFT) calculation. Finally, the probe was utilized to image ClO- in lysosomes of living cells.

18.
Food Chem Toxicol ; 137: 111177, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32028014

RESUMO

Bisphenol A (BPA) can inhibit the differentiation and function of regulatory T cells (Treg), and affect the balance of helper T cell (Th) 1/Th2, therefore, the immunotoxicity of BPA has attracted widespread attention in recent years, but its mechanism is not clear. The main aim of this study was to explore the regulatory mechanism of the PI3K/Akt/mTOR signaling pathway in the context of perinatal exposure to BPA-induced Treg/Th17 imbalance in male offspring mice through a combination of in vivo and in vitro methods. Our results showed that perinatal exposure to BPA could increase the number of Th17 cells while decreasing Treg cell numbers, which was consistent with the expression levels of up-regulation of RORγt protein and a down-regulation FOXP3 protein in the splenocytes of the male offspring mice. BPA could activate the PI3K/Akt/mTOR signaling pathway and increase the inflammatory response, as evidenced by higher serum IL-17 and TNF-α levels by inducing the activation of the AhR and TLR4/NF-κB signaling pathways. Moreover, our results also supported the hypothesis whereby the Treg/Th17 imbalance, induced by perinatal exposure to BPA, was associated with the activation of PI3K/Akt/mTOR signaling in vitro-cultured peripheral blood mononuclear cells by using rapamycin as an inhibitor of mTOR.

19.
J Phys Chem Lett ; : 1255-1260, 2020 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-31990572

RESUMO

Circularly polarized luminescent (CPL) materials are promising in applications such as 3D displays and quantum communication. Hybrid organic-inorganic copper(I) iodides have been rapidly developed due to their intense photoluminescence and structural diversity; nevertheless, the reported Cu-I clusters rarely show CPL activities. In this study, we introduced chiral organic molecules R/S-methylbenzylammonium (R/S-MBA) into Cu-I inorganic skeletons to achieve chiral tetranuclear (R/S-MBA)4Cu4I4 clusters with intense orange luminescence and CPL activity at room temperature. These enantiomeric (R/S-MBA)4Cu4I4 clusters show oppositely signed circular dichroism (CD) signals, which agree well with their simulated electronic CD spectra. The crystallization-induced helical arrangement of (R/S-MBA)4Cu4I4 clusters and their largely distorted polynuclear configuration demonstrate a new platform for the study of chiral-related properties.

20.
Nat Commun ; 11(1): 170, 2020 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-31924790

RESUMO

Reduced-dimensional perovskites are attractive light-emitting materials due to their efficient luminescence, color purity, tunable bandgap, and structural diversity. A major limitation in perovskite light-emitting diodes is their limited operational stability. Here we demonstrate that rapid photodegradation arises from edge-initiated photooxidation, wherein oxidative attack is powered by photogenerated and electrically-injected carriers that diffuse to the nanoplatelet edges and produce superoxide. We report an edge-stabilization strategy wherein phosphine oxides passivate unsaturated lead sites during perovskite crystallization. With this approach, we synthesize reduced-dimensional perovskites that exhibit 97 ± 3% photoluminescence quantum yields and stabilities that exceed 300 h upon continuous illumination in an air ambient. We achieve green-emitting devices with a peak external quantum efficiency (EQE) of 14% at 1000 cd m-2; their maximum luminance is 4.5 × 104 cd m-2 (corresponding to an EQE of 5%); and, at 4000 cd m-2, they achieve an operational half-lifetime of 3.5 h.

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