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1.
Sci Adv ; 5(11): eaaw9120, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31803831

RESUMO

Two-dimensional synthetic polymers (2DSPs) are sheet-like macromolecules consisting of covalently linked repeat units in two directions. Access to 2DSPs with controlled size and shape and diverse functionality has been limited because of the need for monomers to retain their crystallinity throughout polymerization. Here, we describe a synthetic strategy for 2DSPs that obviates the need for crystallinity, via the free radical copolymerization of amphiphilic gemini monomers and their monomeric derivatives arranged in a bilayer at solid-liquid interfaces. The ease of this strategy allowed the preparation of 2DSPs with well-controlled size and shape and diverse functionality on solid templates composed of various materials with wide-ranging surface curvatures and dimensions. The resulting 2DSPs showed remarkable mechanical strength and have multiple applications, such as nanolithographic resist and antibacterial agent. The broad scope of this approach markedly expands the chemistry, morphology, and functionality of 2DSPs accessible for practical applications.

2.
Chem Commun (Camb) ; 2019 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-31803869

RESUMO

Herein, we evaluate the suitablity of polystyrenes with thiol, dithioester and trithiocarbonate end-groups for the synthesis of Al nanocrystals. Both the end-groups and molecular weight of the polymer ligands play important roles for controlling the size and shape of the Al nanocrystals. A general criterion for evaluating polymers as the ligand for the synthesis of Al nanocrystals is proposed.

3.
J Proteome Res ; 2019 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-31755721

RESUMO

Macular neovascular disease is a group disorder with complex pathogenesis of neovascularization for vision impairment and irreversible blindness, posing great challenges to precise diagnosis and management. We prospectively recruited participants with age-related macular degeneration (AMD), polypoidal choroidal vasculopathy (PCV) and pathological myopia (PM), compared with cataract patients without fundus diseases as control group. The serum metabolome was profiled by gas chromatography coupled with time-of-flight mass spectrometry (GC-TOFMS) analysis. Multivariate statistical methods as well as data mining were performed for interpretation of macular neovascularization. A total of 446 participants with macular neovascularization and 138 cataract subjects as control group were enrolled in this study. By employing GC-TOFMS, 131 metabolites were identified and 33 differentiating metabolites were highlighted in patients with macular neovascularization. For differential diagnosis, 3 panels of specific metabolomics-based biomarkers provided areas under the curve of 0.967, 0.938 and 0.877 in the discovery phase (n= 328), predictive values of 87.3%, 79% and 85.7% in the test phase (n= 256). Personalized pathway dysregulation scores measurement using lilikoi package in R language revealed pentose phosphate pathway and mitochondrial electron transport chain as the most important pathways in AMD; purine metabolism and glycolysis were identified as the major disturbed pathways in PCV while the altered thiamine metabolism and purine metabolism may contribute to PM phenotypes. Serum metabolomics are powerful for characterizing metabolic disturbances of macular neovascular. Differences in metabolic pathways may reflect underlying macular neovascularand serve as therapeutic targets for macular neovascular treatment.

4.
Opt Express ; 27(21): 30517-30529, 2019 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-31684298

RESUMO

Injecting radio frequency (RF) white noise to the current driving of the laser can broaden the laser emission linewidth and efficiently suppress cavity-mode noise in off-axis integrated cavity output spectroscopy (OA-ICOS). The effect of the injected RF noise level on the cavity-mode noise and the deformation of the absorption line shape in off-axis integrated cavity output spectroscopy (OA-ICOS) with a distributed feedback laser (DFB) at 1.65 µm were investigated. We measured methane at different concentrations between 0.1 ppmv and 2 ppmv associated with a -20 dBm RF noise injection. A linear spectral response of the intensity of the cavity output spectra with the CH4 concentration was observed. A threefold improvement in the detection limit was achieved compared to unperturbed OA-ICOS. The response time of the improved OA-ICOS system is about 30 s and the minimum detectable concentration (MDC) of CH4 is 7.6 ppbv, which corresponds to a minimum detectable fractional absorption scaled to the path length of 7.3 × 10-10 cm-1. The noise equivalent absorption sensitivity of the system is 5.51 × 10-9 cm-1Hz-1/2.

5.
Opt Express ; 27(20): 27726-27736, 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31684535

RESUMO

The Au@SiO2 nanorods with two plasmonic resonance bands are used to enhance and tune the emission of binary lanthanide (Eu/Tb) complexes. The emissions of Tb and Eu ions are both enhanced, the maximum enhancement is over 100-fold. Meanwhile the ratio and relative intensity of the red/green bands is altered by the strong coupling between complexes and nanorods, tuning the color of emission from green to yellow under excitation of 292 nm and improving the color purity from orange to red under excitation of 360 nm. The underlying physics of the lanthanide complex-plasmonic nanorod composite system is analyzed, which deepen the understanding of the interaction between complexes and plasmon nanoparticles.

6.
Opt Express ; 27(20): 28123-28132, 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31684570

RESUMO

This paper reports a torsion sensor based on the multimode interference theory. The sensor is fabricated by sandwiching a section of perfluorinated polymer optical fiber (POF) between two silica single mode fibers to construct a single-mode-multimode-single-mode (SMS) structure. The perfluorinated POF is easily connected to the optical fiber via the precise alignment of ceramic ferrules and ceramic mating sleeve. With the considerable flexibility and deformability of the perfluorinated POF, the proposed sensor is especially suitable for torsion measurement. Experimental results show that a wavelength sensitivity of 106.762 pm/(rad/m) and an intensity sensitivity of 0.165 dBm/(rad/m) are obtained within a large torsion rate of -100∼100 rad/m.

7.
Biomed Microdevices ; 21(4): 96, 2019 11 11.
Artigo em Inglês | MEDLINE | ID: mdl-31712916

RESUMO

Isothermal titration calorimetry (ITC) can benefit from operating in miniaturized devices as they enable quantitative, low-cost measurements with reduced analysis time and reagents consumption. However, most of the existing devices that offer ITC capabilities either do not yet allow proper control of reaction conditions or are limited by issues such as evaporation or surface adsorption caused inaccurate solution concentration information and unintended changes in biomolecular properties because of aggregation. In this paper, we present a microdevice that combines 3D-printed microfluidic structures with a polymer-based MEMS thermoelectric sensor to enable quantitative ITC measurements of biomolecular interactions. Benefitting from the geometric flexibility of 3D-printing, the microfluidic design features calorimetric chambers in a differential cantilever configuration that improves the thermal insulation and reduces the thermal mass of the implementing device. Also, 3D-printing microfluidic structures use non-permeable materials to avoid potential adsorption. Finally, the robustness of the polymeric MEMS sensor chip allows the device to be assembled reversibly and leak-free, and hence reusable. We demonstrate the utility of the device by quantitative ITC characterization of a biomolecular binding system, ribonuclease A (RNase A) bind with cytidine 2'-monophosphate (2'CMP) down to a practically useful sample concentration of 0.2 mM. The thermodynamic parameters of the binding system, including the stoichiometry, equilibrium binding constant, and enthalpy change are obtained and found to agree with values previously reported in the literature.

8.
J Org Chem ; 2019 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-31755260

RESUMO

I2/dimethyl sulfoxide (DMSO)-mediated C-S, S-N, and C-N bond cross-coupling cyclization reaction for the synthesis of 5-acyl-1,2,3-thiadiazoles from enaminones, tosylhydrazine, and elemental sulfur has been developed under transition-metal-free conditions. This strategy is operationally simple, compatible with a wide range of functional groups, and provides the desired products in moderate to excellent yields.

9.
Aging (Albany NY) ; 11(22): 10316-10337, 2019 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-31743108

RESUMO

Identification of novel clinical biomarker in clear cell renal carcinoma (ccRCC) is warranted. Integrating transcriptome (n=1669), DNA methylation (n=577) and copy number data (n=832), we developed a method to identify driver biomarkers by analyzing the omics-level dynamics of Epithelial-Mesenchymal Transition (EMT)-related genes in ccRCC. We first identified 504 expression dynamic changed genes involved in ccRCC-associated key pathways such as EMT, cell cycle, EGFR and PI3K/AKT signaling. Further analysis identified 229 (90 gene promoters) aberrant expression quantitative trait methylation (eQTM) and 256 genes with expression quantitative trait copy number (eQTCN) alterations. Among them, FOXM1 was affected by both eQTM and eQTCN. FOXM1 copy number amplification (115/500, 23% of patients), occurred in an amplified peak in chromosome 12q13.3, was enriched in late-stage ccRCC samples and was associated with worse survival. FOXM1-overexpressed pT3 patients with distant metastasis showed ~25% shorter overall survival in both training (log-rank P=0.006) and validation (log-rank P=0.018) cohorts. The eQTM-gene hybrid signature (cg00044170 and FOXM1), superior to either gene expression or DNA methylation alone, showed great potential in diagnosing localized ccRCC in training (area under curve = 0.958) and validation datasets. FOXM1 could be a novel prognostic biomarker and shed light for early diagnosis at molecular level in ccRCC.

10.
BMC Pediatr ; 19(1): 427, 2019 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-31711451

RESUMO

BACKGROUND: While caudal block has been widely used during pediatric lower limbs and lower abdominal surgeries, few studies to date have evaluated the perioperative effects of caudal block on pediatric patients in laparoscopic upper urinary tract surgery. METHODS: Ninety-six pediatric patients, aged 6 months to 7 years, ASA grade I-II, scheduled to undergo laparoscopic upper urinary tract surgery, were randomized to a non-block group (no caudal block performed), an ROP1.0 group (patients received 1.0 mL/kg of 0.15% ropivacaine) and an ROP1.3 group (patients received 1.3 mL/kg of 0.15% ropivacaine). The primary outcome variable was perioperative fentanyl use. The secondary outcome variables were pain score, hemodynamic fluctuation, the number of patients needing rescue fentanyl and side effects. RESULTS: Caudal block with 1.3 mL/kg of 0.15% ropivacaine significantly decreased perioperative fentanyl usage (ROP 1.3 vs. non-caudal block, P < 0.01; ROP 1.3 vs. ROP 1.0, P < 0.05). Moreover, patients in the ROP1.3 group, compared to those without, displayed more stable hemodynamics, lower pain score in the PACU and 8 h after operation, less demand for rescue fentanyl, shorter time of PACU stay. CONCLUSIONS: Caudal block with 1.3 mL/kg of 0.15% ropivacaine reduced perioperative fentanyl use during laparoscopic upper urinary tract surgery on pediatric patients and produced good postoperative analgesia when compared with no caudal block and caudal block with 1.0 mL/kg of 0.15% ropivacaine. TRIAL REGISTRATION: Clinical trial number: ChiCTR1800015549, chictr.org.cn.

11.
Clin Neurol Neurosurg ; 187: 105573, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31706107

RESUMO

OBJECTIVE: Advanced techniques such as volumetric-modulated arc therapy (VMAT) may reduce radiation damage and improve the quality of life for patients.We performed a study comparing dose distributions to the planning target volumes(PTVs) and other organs at risk (OARs) of intensity-modulated radiotherapy (IMRT),coplanar VMAT (coVMAT), and non-coplanar VMAT (ncVMAT). PATIENTS AND METHODS: 13 patients with GBM who had undergone postoperative radiotherapy were enrolled. Three plans for each patient were created, namely, IMRT, coVMAT, and ncVMAT. Prescription doses and normal-tissue constraints were identical for these three plans. The dosimetric differences of target dose distribution, conformity index (CI), homogeneity index (HI), the gradient index (GI), dose of OARs, monitor units (MUs) and beam-on times among these three plans were investigated. RESULTS: These three techniques resulted in comparable maximum, minimum, and mean PTV doses. Small but insignificant differences were observed in GI,CI, and HI. Compared with IMRT, VMAT plans showed statistically significant reductions in the mean doses to the optic chiasm (P < 0.05). Compared with IMRT, VMAT techniques significantly reduced the number of MUs and less beam-on time than IMRT techniques (P < 0.05). However, calculation times were significantly longer for ncVMAT and coVMAT plans at 12 and 12.3 min, versus 2.6 min for IMRT. Our study showed that IMRT or VMAT planning is feasible and efficient for patients with GBM.Compared to IMRT plans, ncVMAT or coVMAT plans showed similar PTV coverage and comparable OARs sparing. VMAT plans significantly reduces the mean doses to the optic chiasm than IMRT plans. CONCLUSION: There was no obvious superiority of ncVMAT over coVMAT in target coverage and sparing of OARs.Compared with IMRT, VMAT techniques significantly reduced the number of MUs and beam-on time but extended the calculation times.

12.
Drug Des Devel Ther ; 13: 3117-3126, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31695328

RESUMO

Aim: Diabetic nephropathy (DN) is the leading cause of end-stage renal disease. Silibinin is a flavonoid compound which has medicinal value. Previous studies revealed that silibinin exhibited an anti-fibrotic effect. However, whether silibinin could attenuate high-fat diet (HFD)-induced renal fibrosis remains unclear. Therefore, this study aimed to explore the molecular mechanism by which silibinin regulated renal fibrosis induced by HFD. Methods: In the present study, human renal glomerular endothelial cells (HRGECs) were treated with various concentrations of silibinin. Then, cell viability and apoptosis were measured by MTT assay and flow cytometry, respectively. In addition, HRGECs were exposed to 100 nM TGF-ß1 for mimicking in vitro renal fibrosis. The expressions of collagen I, fibronectin, and α-SMA were detected by reverse transcription-quantitative polymerase chain reaction and Western blot. Protein levels of p-IκB and p-p65 were examined by Western blot; meanwhile, level of NF-κB was measured by immunofluorescence staining. Furthermore, HFD-induced mouse model of renal fibrosis was established. The mouse body weight, fasting glucose, kidney weight/body weight, microalbuminuria, kidney histopathology, and fibrotic area were measured to assess the severity of renal fibrosis. Results: Low concentration of silibinin (≤50 µM) had no cytotoxicity, while high concentration of silibinin (≥75 µM) exhibited significant cytotoxicity. Additionally, TGF-ß1 increased the expressions of collagen I, fibronectin, α-SMA, p-IκB, and p-p65 and decreased the level NF-κB, while these effects were notably reversed by 50 µM silibinin. Moreover, both 50 and 100 mg/kg silibinin greatly decreased HFD-induced the upregulation of kidney weight/body weight, microalbuminuria, and fibrotic area. 100 mg/kg silibinin markedly reduced collagen I, fibronectin, and p-p65 expressions in mice renal tissues. Conclusion: Silibinin was able to attenuate renal fibrosis in vitro and in vivo via inhibition of NF-κB. These data suggested that silibinin may serve as a potential agent to alleviate the renal fibrosis of DN.

13.
BMC Cancer ; 19(1): 1070, 2019 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-31703643

RESUMO

BACKGROUND: Increase of circulating tumor cells (CTCs) has been found after surgery for various carcinomas but not confirmed for breast cancer, and whether endoscopic surgery confers identical effect to CTCs as open surgery did is not clear. The present study aimed to investigate whether CTCs increase after surgery and whether there is a difference between open surgery and endoscopic surgery. METHODS: Pre- and postoperative peripheral blood (5 mL) obtained from 110 female patients with operable breast cancer (53 underwent endoscopic surgery, 57 underwent open radical mastectomy). Quantitative real-time reverse transcription-PCR was done to detect cytokeratin 19 mRNA-positive CTC. CTC detection rate, cell number and the increase after surgery (named micrometastasis) were compared between the two groups. RESULTS: In the open group, CTC positive rate before and after surgery were 22.81 and 33.33%; median CTC number before and after surgery were 0.21 and 0.43 and 17 patients (29.82%) had increased micrometastatic risk. In the endoscopic group, CTC positive rate before and after surgery were 24.53 and 28.30%; median CTC number before and after surgery were 0.27 and 0.36, and 8 patients (15.09%) had increased micrometastatic risk. There was a suggestive higher postoperative CTC detection rate and CTC number and a significant increased postoperation micrometastatic risk was observed in the open group compared to the endoscopic group (OR = 3.19, 95%CI: 1.05-9.65) after adjustment for clinicopathologic characteristics. DISCUSSION: CTC tends to increase in breast cancer patients after surgery, and the micrometastatic risk was higher for open surgery compared to endoscopic surgery. TRIAL REGISTRATION: This study was prospectively registered at Chinese Clinical Trial Register (ChiCTR-OCH-10000859, 24 April 2010).

14.
Artigo em Inglês | MEDLINE | ID: mdl-31691293

RESUMO

PURPOSE: The aim of this study was to assess the validity and reliability of the Chinese version of mental vulnerability questionnaire (MVQ) for undergraduate students. DESIGN AND METHODS: A cross-sectional design was conducted in a sample of 1217 undergraduate students. FINDINGS: The Cronbach's α of the overall scale was 0.901, the split-half reliability coefficient was 0.742, and the test-retest reliability coefficient was 0.935. Three-factors model was got by using exploratory factor analysis, the communalities of the items were 0.646 to 0.848, explaining 75.736% variance. With confirmatory factor analysis the fit indices were chi-square/degree of freedom (CMIN/DF) = 2.796, comparative fit index (CFI) = 0947, GFI = 0.920, adjustedgoodness of fit index (AGFI) = 0.902, incremental fit index (IFI) = 0.947, root mean squareerror of approximation (RMSEA) = 0.055, Tucker Lewis index (TLI) = 0.940, root mean residual (RMR) = 0.051. PRACTICE IMPLICATIONS: The Mental Vulnerability Questionnaire has a good reliability and validity, it can be considered as a tool to evaluate the mental vulnerability for undergraduate students.

16.
Artigo em Inglês | MEDLINE | ID: mdl-31682264
17.
Cancer Biomark ; 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31771044

RESUMO

FoxO3a is a well-defined tumor suppressor gene in the forkhead transcription factor O subfamily (FoxO), and its reduction is related to the occurrence of various tumors. It was found that the expression of miR-155 is abnormally elevated in oral cancer tissues, suggesting that miR-155 may be a tumor-promoting gene for oral cancer. Bioinformatics analysis revealed a targeted complementary binding site between miR-155 and FoxO3a. In this study, we established a cisplatin-resistant cell line of oral cancer to compare the expression of miR-155 and FoxO3a in parental oral cancer cells, and explore whether miR-155 regulates the expression of FoxO3a and affects the proliferation and apoptosis of oral cancer cells. Dual luciferase reporter gene assay validated the targeted regulatory role between miR-155 and FoxO3a. The DDP-resistant oral cancer cell line KB/DDP was established, and the expressions of miR-155 and FoxO3a were compared. The CCK-8 assay was used to calculate the resistance index (RI). KB/DDP cells were divided into miR-NC group and miR-155 inhibitor group. Cell apoptosis was detected by flow cytometry. Cell proliferation ability was detected by EdU staining. There is a targeted regulatory relationship between miR-155 and FoxO3a mRNA. The expression of miR-155 was significantly higher, while the expression of Foxo3a mRNA and protein was obviously lower in KB/DDP cells than that in KB cells. CCK-8 experiments showed that the same concentration of DDP exhibited apparently lower proliferation inhibition in KB/DDP cells than KB cells. Compared with the miR-NC group, transfection of miR-155 inhibitor markedly increased the expression of Foxo3a in KB/DDP cells, which significantly attenuated cell proliferation and enhanced apoptosis in DDP-treated cells. Increased expression of miR-155 and decreased expression of Foxo3a were associated with DDP resistance in oral cancer cells. Inhibition of miR-155 expression upregulated Foxo3a expression, restrained oral cancer cell proliferation, promoted cell apoptosis, and enhanced DDP sensitivity in oral cancer cells.

18.
Adv Exp Med Biol ; 1206: 489-508, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31777000

RESUMO

Autophagy, the intracellular degradation and dynamic recycling system, plays critical roles in pluripotent and differentiated cells. It protects the homeostasis of the intracellular environment and maintains the functions of cells by degrading and recycling cytoplasmic components. Autophagy is associated with the entire life cycle of the body, from the totipotent fertilized egg to the terminally differentiated cell. However, autophagy also plays distinct roles in these different life stages and in specific cell types. Here, we summarize the functions of autophagy in normal stem cells and in specialized cells.

20.
Artigo em Inglês | MEDLINE | ID: mdl-31656161

RESUMO

OBJECTIVES: This study is to discover potential cytokine biomarker for early diagnosis of thyroid cancer. METHODS: We employed data mining The Cancer Genome Atlas (TCGA) and experimentally elucidated its mechanistic contributions, the differential expression genes (DEGs) between thyroid cancer and health population were analyzed with TCGA online bioinformatic tools. The relative expression of Bone Morphogenetic Protein 8A (BMP8A) was determined by real-time PCR in ultrasonic diagnosed thyroid cancer both in vivo and in vitro. The serous BMP8A content was quantified with ELISA kit. Protein levels of BMP8A, OCLN, ZEB1, EZH2 and ß-Actin were analyzed by western blotting. Cell viability was measured by MTT assay and anchorage-independent growth was measured by soft agar colony formation assay. Cell migrative and invasive capacities were interrogated with transwell chambers. RESULTS: We identified aberrant high-expression of BMP8A in thyroid cancer, which associated with unfavorable prognosis and tumor progression. The serous BMP8A was significantly up-regulated in thyroid cancer patients as well. Ectopic over-expression of BMP8A remarkably stimulated cell viability and anchorage-independent growth. Meanwhile, the migrative and invasive capacities were greatly increased in response to BMP8A over-expression. Mechanistically, we characterized positive correlation between BMP8A and TCF7L1, and forced expression of TCF7L1 induced increase of BMP8A in TPC-1 cells. CONCLUSION: In summary, we identified a novel biomarker for early diagnosis in addition to Ultrasound of thyroid cancer, which was subjected to TCF7L1 regulation.

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