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1.
Heart Rhythm ; 2019 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-31513946

RESUMO

BACKGROUND: Ondansetron, a widely prescribed antiemetic, has been implicated in drug-induced long QT syndrome. Recent patch clamp experiments have shown that ondansetron inhibits the apamin sensitive calcium activated potassium current (IKAS). OBJECTIVE: To determine if ondansetron causes action potential duration (APD) prolongation by IKAS inhibition. METHODS: Optical mapping was performed in rabbit hearts with pacing induced heart failure (HF) and in normal hearts before and after ondansetron (100 nM) infusion. APD at 80% repolarization (APD80) and arrhythmia inducibility were determined. Additional studies with ondansetron were performed in normal hearts perfused with a hypokalemia (2.4 mM) solution before or after apamin. RESULTS: The QTc interval in HF was 326 ms [95% CI, 306-347] at baseline and 364 ms [95% CI, 351-378] after ondansetron (p<0.001). Ondansetron significantly prolonged the APD80 in the HF group and promoted early afterdepolarizations, steepened the APD restitution curve and increased ventricular vulnerability. VF was not inducible in the HF ventricles at baseline, but after ondansetron infusion, VF was induced in 5 of 7 ventricles (P=0.021). In hypokalemia, apamin prolonged the APD80 from 163 ms [CI, 146-180] to 180 ms [95% CI, 156-204] (P=0.018). Subsequent administration of ondansetron failed to further prolong APD80 (180 ms [95% CI, 156-204] vs 179 ms [95% CI, 165-194], P=0.789). The results were similar when ondansetron was administered first followed by apamin. CONCLUSIONS: Ondansetron is a specific IKAS blocker at therapeutic concentrations. Ondansetron may prolong the QT interval in HF by inhibiting SK channels which increases the vulnerability to ventricular arrhythmias.

2.
Opt Express ; 27(15): 20358-20372, 2019 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-31510131

RESUMO

Compared to glass walls with a positive curvature, those with a negative curvature have been proven to have stronger confinement of light. Therefore, we change the multi-layered air holes in a photonic crystal fiber into several negative curvature tubes. As a result, the confinement medium is shifted from a low-index cladding material into a special structure. The theoretical analysis shows that each vector eigenmode has a corresponding threshold value for the outer tube thickness. It means that we can confine the target modes and filter the unnecessary modes by shifting the outer tube thickness. After substantial investigation on this fiber, we obtain the appropriate values for each structural parameter and then fabricate this negative curvature ring-core fiber under the guidance of the simulation results. Firstly, we draw the central cane under vacuum condition, then stack the cane and six capillaries to form the preform, and finally draw the ring-core fiber by using vacuumization method. The fiber test experiment indicates that the fiber length should be at least 15 m∼20 m to form the donut facula, and the tested losses of OAM+1,1, OAM+2,1, OAM+3,1, and OAM+4,1 are 0.30 dB/m, 0.36 dB/m, 0.37 dB/m, and 0.42 dB/m, respectively.

3.
J Transl Med ; 17(1): 308, 2019 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-31511014

RESUMO

BACKGROUND: Estrogen receptors (ERs) are thought to play an important role in non-small cell lung cancer (NSCLC). However, the effect of ERs in NSCLC is still controversial and needs further investigation. A new consideration is that ERs may affect NSCLC progression through complicated molecular signaling networks rather than individual targets. Therefore, this study aims to explore the effect of ERs in NSCLC from the perspective of cancer systems biology. METHODS: The gene expression profile of NSCLC samples in TCGA dataset was analyzed by bioinformatics method. Variations of cell behaviors and protein expression were detected in vitro. The kinetic process of molecular signaling network was illustrated by a systemic computational model. At last, immunohistochemical (IHC) and survival analysis was applied to evaluate the clinical relevance and prognostic effect of key receptors in NSCLC. RESULTS: Bioinformatics analysis revealed that ERs might affect many cancer-related molecular events and pathways in NSCLC, particularly membrane receptor activation and signal transduction, which might ultimately lead to changes in cell behaviors. Experimental results confirmed that ERs could regulate cell behaviors including cell proliferation, apoptosis, invasion and migration; ERs also regulated the expression or activation of key members in membrane receptor signaling pathways such as epidermal growth factor receptor (EGFR), Notch1 and Glycogen synthase kinase-3ß/ß-Catenin (GSK3ß/ß-Catenin) pathways. Modeling results illustrated that the promotive effect of ERs in NSCLC was implemented by modulating the signaling network composed of EGFR, Notch1 and GSK3ß/ß-Catenin pathways; ERs maintained and enhanced the output of oncogenic signals by adding redundant and positive-feedback paths into the network. IHC results echoed that high expression of ERs, EGFR and Notch1 had a synergistic effect on poor prognosis of advanced NSCLC. CONCLUSIONS: This study indicated that ERs were likely to promote NSCLC progression by modulating the integrated membrane receptor signaling network composed of EGFR, Notch1 and GSK3ß/ß-Catenin pathways and then affecting tumor cell behaviors. It also complemented the molecular mechanisms underlying the progression of NSCLC and provided new opportunities for optimizing therapeutic scheme of NSCLC.

4.
J Nanobiotechnology ; 17(1): 93, 2019 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-31481080

RESUMO

Exosomes (Exo) hold great promise as endogenous nanocarriers that can deliver biological information between cells. However, Exo are limited in terms of their abilities to target specific recipient cell types. We developed a strategy to isolate Exo exhibiting increased binding to integrin αvß3. Binding occurred through a modified version of a disintegrin and metalloproteinase 15 (A15) expressed on exosomal membranes (A15-Exo), which facilitated co-delivery of therapeutic quantities of doxorubicin (Dox) and cholesterol-modified miRNA 159 (Cho-miR159) to triple-negative breast cancer (TNBC) cells, both in vitro and in vivo. The targeted A15-Exo were derived from continuous protein kinase C activation in monocyte-derived macrophages. These cell-derived Exo displayed targeting properties and had a 2.97-fold higher production yield. In vitro, A15-Exo co-loaded with Dox and Cho-miR159 induced synergistic therapeutic effects in MDA-MB-231 cells. In vivo, miR159 and Dox delivery in a vesicular system effectively silenced the TCF-7 gene and exhibited improved anticancer effects, without adverse effects. Therefore, our data demonstrate the synergistic efficacy of co-delivering miR159 and Dox by targeted Exo for TNBC therapy.

5.
Eur J Med Chem ; 181: 111598, 2019 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-31415981

RESUMO

A class of novel δ-sulfonolactone-fused pyrazole scaffold was prepared via sulfur (VI) fluoride exchange (SuFEx) chemistry using aryl sulfonyl fluorides and pyrazolones. Enzyme screening revealed their cholinesterase inhibitory activity, among them, compounds 4a, 5a and 5d were identified as highly selective submicromolar BuChE inhibitors (IC50 = 0.20, 0.46 and 0.42 µM, respectively), which exhibited nontoxicity, lipophilicity and remarkable neuroprotective activity. Kinetic studies showed that BuChE inhibition of compounds 5a and 5d was reversible, mixed-type and non-competitive inhibition against BuChE (Ki = 145 nM and 60 nM, respectively). Compound 5d can be accommodated into hBuChE via π-S interaction and hydrophobic interactions. The title compounds are potentially symptomatic treatment in progressive Alzheimer's disease.

6.
Anal Chim Acta ; 1081: 184-192, 2019 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-31446957

RESUMO

Hypochlorite (ClO-), one of reactive oxygen species (ROS), is closely related with many physiological and pathological processes. Especially as one of cellular reactive oxygen species in mitochondria, ClO- can induce mitochondrial permeability, which leads to apoptosis. Thus, developing an effective method which is able to sense ClO- in mitochondria is important. Although fluorescent probe has become a powerful tool for imaging ClO- in mitochondria, most of them suffered from phototoxicity to biosamples, autofluorescence, and photobleaching phenomenon due to their short-wavelength excitations and emissions. Based on advantages of two-photon fluorescent probe and far-red to NIR fluorescent probe, a mitochondria-targetable two-photon fluorescent probe with a turn-on signal in far-red to NIR region, Mito-TP-ClO, was developed for ClO- in this paper. Mito-TP-ClO is consisted of a triphenylphosphonium cations as a mitochondria-targetable unit and a structure of dibenzoylhydrazine as a response unit to ClO-. Mito-TP-ClO exhibited a high sensitivity and a high selectivity to ClO-, with a linear range from 6.0 × 10-8 to 1.0 × 10-5 M and a detection limit of 2.5 × 10-8 M. Due to its large two-photon cross section (267 GM) and far-red to NIR emission, Mito-TP-ClO exhibits excellent performances including low autofluorescence, photostable fluorescence signal, and deep tissue penetration (230 µM). Moreover, Mito-TP-ClO was successfully used to detect endogenous ClO- in bacteria-infected cells and inflammatory mouse model, which confirmed that Mito-TP-ClO is a powerful tool to monitor ClO- in mitochondria and study on effects of hypochlorite on mitochondria.

7.
Nat Commun ; 10(1): 3856, 2019 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-31451693

RESUMO

Accurate prediction of chemo- or targeted therapy responses for patients with similar driver oncogenes through a simple and least-invasive assay represents an unmet need in the clinical diagnosis of non-small cell lung cancer. Using a single-cell on-chip metabolic cytometry and fluorescent metabolic probes, we show metabolic phenotyping on the rare disseminated tumor cells in pleural effusions across a panel of 32 lung adenocarcinoma patients. Our results reveal extensive metabolic heterogeneity of tumor cells that differentially engage in glycolysis and mitochondrial oxidation. The cell number ratio of the two metabolic phenotypes is found to be predictive for patient therapy response, physiological performance, and survival. Transcriptome analysis reveals that the glycolytic phenotype is associated with mesenchymal-like cell state with elevated expression of the resistant-leading receptor tyrosine kinase AXL and immune checkpoint ligands. Drug targeting AXL induces a significant cell killing in the glycolytic cells without affecting the cells with active mitochondrial oxidation.

8.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 27(4): 1053-1057, 2019 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-31418356

RESUMO

OBJECTIVE: To investigate the relationship of PTEN/PI3K/AKT signaling pathway protein expression with apoptosis and drug-resistance of children's ALL primary cells treated with daunorubicin (DNR). METHODS: The bone marrow mononuclear cells in newly diagnosed and untreated B-ALL children were collected and cultured. After the treatment of primary-cultured cells with DNR of final concentration 0.5 mg/L for 24 h, the cell apoptosis rate was detected by using cell apoptosis assay kit; the samples were collected at the on test of culture and after drug treatment, then expression levels of PTEN, PI3K and AKT proteins were detected by Western blot, moreover the interindex correlation was analyzed. RESULTS: After DNR treatment, the apoptosis rate in PTEN low expression group was lower than that in PTEN high expression group (P<0.05), showing high positive correlation of the cell apoptosis rate with the expression of PTEN before DNR treatment; the cell apoptosis rate in PI3K and AKT low expression group was higher than that in PI3K and AKT high expression group (P<0.01); however, the expression of PI3K and AKT proteins was down-regulated after treatment with DNR (P<0.01). CONCLUSION: The difference of PTEN expression is present in primary cells of B-ALL children, however the change of PTEN expression is not significant after DNR treatment, suggesting that the PTEN expression correlates with DNR-resistance. The DNR can induce the apoptosis of childrens B-ALL primary cells by down-regulating the expression of PI3K and AKT signaling pathway proteins.


Assuntos
Transdução de Sinais , Apoptose , Criança , Daunorrubicina , Humanos , PTEN Fosfo-Hidrolase , Fosfatidilinositol 3-Quinases , Proteínas Proto-Oncogênicas c-akt
9.
Artigo em Inglês | MEDLINE | ID: mdl-31443033

RESUMO

Previous studies have indicated that amputation induces reorganization of functional brain network. However, the influence of amputation on structural brain network remains unclear. In this study, using diffusion tensor imaging (DTI), we aimed to investigate the alterations in fractional anisotropy (FA) network after unilateral upper-limb amputation. We acquired DTI from twenty-two upper-limb amputees (15 dominant-side and 7 nondominant-side amputees) as well as fifteen healthy controls. Using DTI tractography and graph theoretical approaches, we examined the topological changes in FA network of amputees. Compared with healthy controls, dominant-side amputees showed reduced global mean strength, increased characteristic path length, and decreased nodal strength in the contralateral sensorimotor system and visual areas. In particular, the nodal strength of the contralateral postcentral gyrus was negatively correlated with residual limb usage, representing a use-dependent reorganization. In addition, the nodal strength of the contralateral middle temporal gyrus was positively correlated with the magnitude of phantom limb sensation. Our results suggested a degeneration of FA network after dominant-side upper-limb amputation.

10.
Mol Cell Probes ; : 101435, 2019 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-31415867

RESUMO

Currently in China, porcine epidemic diarrhea virus (PEDV), transmissible gastroenteritis virus (TGEV), porcine rotavirus (PoRV), and porcine deltacoronavirus (PDCoV) are the major causes of porcine viral diarrhea, and mixed infections in clinics are common, resulting in significant economic losses in pig industry. Here, a dual priming oligonucleotide (DPO)-based multiplex real-time SYBR Green RT-PCR assay were developed for accurately differentiating PEDV, TGEV, PoRV, and PDCoV in clinical specimens targeting the N gene of TGEV, PEDV, and PDCoV, and the VP7 gene of PoRV. Results showed that the DPO primer allowed a wider annealing temperature range (40-65 °C) and had a higher priming specificity compared to conventional primer, in which more than 3 nucleotides in the 3'- or 5'-segment of DPO primer mismatched with DNA template, PCR amplification efficiency would decrease substantially or extension would not proceed. DPO-based multiplex real-time RT-PCR method had analytical detection limit of 8.63 × 102 copies/µL, 1.92 × 102 copies/µL, 1.74 × 102 copies/µL, and 1.76 × 102 copies/µL for PEDV, TGEV, PoRV, and PDCoV in clinical specimens, respectively. A total of 672 clinical specimens of piglets with diarrheal symptoms were collected in Northeastern China from 2017 to 2018 followed by analysis using the assay, and epidemiological investigation results showed that PEDV, TGEV, PoRV, and PDCoV prevalence was 19.05%, 5.21%, 4.32%, and 3.87%, respectively. The assay developed in this study showed higher detection accuracy than conventional RT-PCR method, suggesting a useful tool for the accurate differentiation of the four major viruses causing porcine viral diarrhea in practice.

11.
ACS Appl Mater Interfaces ; 11(33): 29630-29640, 2019 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-31337206

RESUMO

Photothermal conversion efficiency (η) of gold nanorods (GNRs) can be tuned by enlarging the aspect ratio and forming the core-shell structure. Herein, an easy synthesis method is developed to construct the core-shell GNR@LDH nanostructure with GNRs and layered double hydroxides (LDHs). The interaction between Au and LDHs results some electron deficiency on the surface of Au and the more electrons induce more thermal energy conversion. The η value of GNR@LDH can reach up to 60% under the 808 nm laser irradiation, which is a significant enhanced conversion efficiency compared with the reported GNR-based photothermal therapy materials. CTAB (cetyltrimethyl ammonium bromide) can be replaced totally during the synthesis process, and GNRs maintain a good dispersion in LDHs. This core-shell composite GNR@LDH can be applied in photothermal, antibacterial, tumor therapy and biological imaging with low dosage and nontoxicity.

12.
Stem Cell Res ; 39: 101501, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31344652

RESUMO

GA binding protein (GABP) is a ubiquitously expressed transcription factor that regulates the development of multiple cell types, including osteoblast, hematopoietic stem cells, B cells and T cells. However, so little is known about its biological function in the development of central nervous system. In this report, we show that GABP is highly expressed in neural stem/progenitor cells (NSPCs) and down-regulated in neurons, and that GABPß1 is required for the proper proliferation of NSPCs. Knockdown of GABPα resulted in an elevated expression level of GABPß1, and GABPß1 down-regulation significantly decreased the proliferation of NSPCs, whereas GABPß2 knockdown did not result in any changes in the proliferation of NSPCs. We observed that there was nearly a 21-fold increase of the GABPß1S mRNA level in GABPß1L KO NSPCs compared to WT cells, and knocking down of GABPß1S in GABPß1L KO NSPCs could further reduce their proliferation potential. We also found that knockdown of GABPß1 promoted neuronal and astrocytic differentiation of NSPCs. Finally, we identified dozens of downstream target genes of GABPß1, which are closely associated with the cell proliferation and differentiation. Collectively, our results suggest that both GABPß1L and GABPß1S play an essential role in regulating the proper proliferation and differentiation of NSPCs.

13.
Oxid Med Cell Longev ; 2019: 5414670, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31354907

RESUMO

Esophageal cancer (ESC) is one of the most deadly diseases for human. p53 in most cancers, including ESC cell, is mutated, and the mutated p53 losses its original function and acquires "gain of function" that allows for promoting the hallmarks of cancer, such as antiapoptosis, metastasis, invasion, angiogenesis, and resistance to chemotherapy. Targeting p53 through either introducing wild-type or degrading mutated p53 is an important strategy in cancer therapy. Di-2,2'-pyridine ketone dithiocarbamate s-butyric acid (DpdtbA) has significant growth inhibition against gastric cancer lines in previous study. Similar action in ESC cell lines but a novel molecular mechanism was observed in the present study. The results showed that DpdtbA exhibited an excellent antiproliferative effect for ESC cell lines (IC50 ≤ 4.5 ± 0.4 µM for Kyse 450, 3.2 ± 0.6 µM for Kyse 510 cell, and 10.0 ± 0.6 µM for Kyse 150) and led to cell cycle arrest at the S phase which correlated to CDK2 downregulation. The mechanistic study suggested that growth inhibition was related to ROS-mediated apoptosis, and ROS production was due to SOD inhibition initiated by DpdtbA rather than occurrence of ferritinophagy. In addition, DpdtbA also induced a downregulation of EGFR, p53, and AKT, which hinted that mutant p53 still played a role in the regulation of its downstream targets. Further study revealed that the downregulation of p53 was through stub1- (chip-) mediated autophagic degradation rather than MDM2-mediated ubiquitination. Taken together, the DpdtbA-induced growth inhibition in a mechanism was through inactivating the p53/EGFR/AKT signal pathway.

14.
PLoS One ; 14(7): e0220012, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31318952

RESUMO

Orthostatic tremor (OT) is a rare movement disorder characterized by a fast tremor (13-18 Hz) in the lower extremities during stance. Patients with OT typically complain of instability while standing/walking. However, due to the geographical limitation, the standing instability or gait problems in patients with OT cannot be assessed and monitored frequently. The increasing popularity of using smartphone-based accelerometers could be a solution to eliminate this limitation. This study examined the feasibility of using smartphone-based accelerometers to identify the changes in body movement in different standing and locomotor tasks. Twenty patients with OT and seven healthy controls were consented to participate in this study. Subjects stood with eyes open or eyes closed for 20 seconds. They also performed four different locomotor tasks (normal walking, tandem walk, walking on an elevated surface, and obstacle negotiation). When performed different locomotor tasks, patients with OT had a larger acceleration of body movement than controls in the medial-lateral direction (tandem walk: p = 0.026, walking on an elevated surface: p = 0.002, and stepping over the obstacle: p = 0.028). Patients with OT had smaller acceleration of body movement than controls while standing with eyes open in the vertical direction (p = 0.012), in the anterior-posterior direction (p = 0.013) and in the medial-lateral direction (p = 0.011). This study provides objective evidence of balance instability in patients with OT not only while standing but also during different challenging locomotor tasks by using smartphone-based accelerometers.

15.
Nat Plants ; 5(8): 810-821, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31308504

RESUMO

Banana cultivars (Musa ssp.) are diploid, triploid and tetraploid hybrids derived from Musa acuminata and Musa balbisiana. We presented a high-quality draft genome assembly of M. balbisiana with 430 Mb (87%) assembled into 11 chromosomes. We identified that the recent divergence of M. acuminata (A-genome) and M. balbisiana (B-genome) occurred after lineage-specific whole-genome duplication, and that the B-genome may be more sensitive to the fractionation process compared to the A-genome. Homoeologous exchanges occurred frequently between A- and B-subgenomes in allopolyploids. Genomic variation within progenitors resulted in functional divergence of subgenomes. Global homoeologue expression dominance occurred between subgenomes of the allotriploid. Gene families related to ethylene biosynthesis and starch metabolism exhibited significant expansion at the pathway level and wide homoeologue expression dominance in the B-subgenome of the allotriploid. The independent origin of 1-aminocyclopropane-1-carboxylic acid oxidase (ACO) homoeologue gene pairs and tandem duplication-driven expansion of ACO genes in the B-subgenome contributed to rapid and major ethylene production post-harvest in allotriploid banana fruits. The findings of this study provide greater context for understanding fruit biology, and aid the development of tools for breeding optimal banana cultivars.

16.
Phys Ther ; 2019 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-31309974

RESUMO

BACKGROUND: Physical therapists, as clinical human movement experts, must qualitatively evaluate patients' functional and biomechanical impairments. There are now low-cost 2- and 3-dimensional video measurement systems that can be used to increase the precision and reliability of these qualitative clinical assessments. PURPOSE: The purpose of this study was to systematically review current low-cost video-based methods for motion analysis in comparison with gold-standard 3-dimensional biomechanical methods. DATA SOURCES: Electronic searches were conducted until January 2018 within the following databases: MEDLINE via PubMed, CINAHL, Cochrane, Scopus, and IEEE. STUDY SELECTION: Studies designed to evaluate criterion-referenced validity and/or reliability of video-based motion analysis technologies within the last 20 years were included. English-language articles dealing with human rehabilitation were considered. DATA EXTRACTION: Data extraction was independently completed by 3 reviewers, and methodological quality was assessed using the 2018 Consensus-Based Standards for the Selection of Health Measurement Instruments (COSMIN) checklist. Articles were organized for analysis on the basis of type of motion analyzed and category of each low-cost technology used. DATA SYNTHESIS: With 20 articles meeting selection criteria, 10 low-cost motion analysis platforms were presented, each examining different functional movement-dependent variables. Overall article quality was "low" or "very low" on the basis of COSMIN scoring. Correlations between low-cost and 3-dimensional gold standard systems ranged widely from "poor" agreement (r = 0.025) to "strong" agreement (r = 0.992). Spatiotemporal gait parameters consistently outperformed planar joint angle data. Reliability was better measured than concurrent validity. A summary table was developed to assist clinicians in choosing which motions could potentially be measured accurately by each low-cost platform on the basis of current findings. LIMITATIONS: Databases available to researchers were more clinical/medical in nature, and this review was written from that clinically based perspective. Lack of standardized protocols and methodology within included studies was common, making generalizability difficult. CONCLUSIONS: Research attempting to validate newer low-cost movement analysis systems is limited in quality. Measurement of only certain variables should be considered when these tools are used. Further research is warranted, as these devices still have potential clinical utility for supplementing qualitative movement assessment with objective outcome measures.

17.
Mikrochim Acta ; 186(8): 536, 2019 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-31317342

RESUMO

The authors describe TiO2 nanowires (TiO2NWs) for solid-phase microextraction of polycyclic aromatic hydrocarbons (PAHs). Well-oriented TiO2NWs were in-situ grown on a titanium wire by a hydrothermal process. The TiO2NWs arrays are radially aligned on the curved titanium fiber substrate. They possess a large surface area and are readily accessible for subsequent self-assembly of trichlorophenylsilane via formation of Ti-O-Si bonds. The TiO2NWs coated fibers show good extraction selectivity for PAHs as shown for phenathrene, fluoranthene, pyrene and benzo[a]pyrene. Following desoption by mobile phases for HPLC analysis, the PAHs were quantified by HPLC with UV detection. The improved extraction capabilities and good selectivity are explained by synergistic hydrophobic and π stacking interactions between the phenyl moieties and the PAHs. Key parameters that affect the extraction performance of the fibers were optimized. The method has a linear response in the 0.1 to 200 µg·L-1 PAH concentration range. Limits of detection (at S/N = 3) range from 20 to 50 ng·L-1. Relative standard deviations (RSDs) for the single fiber repeatability are less than 7.3% (n = 5) and RSDs for the fiber-to-fiber reproducibility are below 8.1% (n = 5). The method was successfully applied to the selective preconcentration and determination of trace PAHs in spiked water samples. Graphical abstract Schematic presentation of fabrication and characterization of the Ti@TiO2NWs@Phenyl fiber. PAHs: polycyclic aromatic hydrocarbons; UVFs: ultraviolet filters; PAEs: phthalate acid esters; CPs: chlorophenols.

18.
Mar Drugs ; 17(7)2019 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-31337016

RESUMO

Chitooligosaccharides (COS), the only cationic oligosaccharide in nature, have been demonstrated to have anti-tumor activity. However, the inhibitory effects of COS on different stages of tumor metastasis are still unknown, and it is not clear what stage(s) of tumor metastasis COS targeted. To study the inhibitory effects of a new partially acetylated chitooligosaccharide (paCOS) with fraction of acetylation (FA) 0.46 on each phase of liver cancer cell metastasis, a dynamic tumor-vessel microsystem undergoing physiological flow was leveraged. paCOS (FA = 0.46) significantly inhibited proliferation of HepG2 cells through vascular absorption on the chip, and inhibited migration of HepG2 cells by inhibiting the formation of pseudopod in liver tumor cells. It was also found that paCOS at 10 µg/mL had a stronger inhibitory effect on liver tumor cells invading blood vessels than that of paCOS at 100 µg/mL, and paCOS at 100 µg/mL, which had a significant destructive effect on tumor vascular growth and barrier function. Moreover, paCOS reduced the number of liver tumor cells adhering onto the surface of HUVECs layer after 3 h of treatment. Therefore, the results revealed that paCOS had considerable potential as drugs for anti-tumor metastasis.

19.
Int J Biol Sci ; 15(5): 909-918, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31182912

RESUMO

The really interesting new gene (RING) finger protein 8 (RNF8) is a central factor in DNA double strand break (DSB) signal transduction. DSB damage is the most toxic type of DNA damage to cells and is related to genomic instability. Multiple roles for RNF8 have been identified in DNA damage response as well as in other functions, such as telomere protection, cell cycle control and transcriptional regulation. These functions are closely correlated to tumorigenesis and cancer progression. Indeed, deficiency of RNF8 caused spontaneous tumorigenesis in a mouse model. Deciphering these mechanisms of RNF8 may shed light on strategies for cancer treatment. In this review, we summarize the current understanding of both classical and nonclassical functions of RNF8, and discuss its roles in the pathogenesis and progression of tumor.

20.
Artigo em Inglês | MEDLINE | ID: mdl-31180929

RESUMO

OBJECTIVE: The aim of this review is to evaluate and summarize the results of published studies exploring the effects of expiratory muscle strength training (EMST) on swallowing and cough functions in patients with neurological diseases. DATA SOURCES: Embase, PubMed, and the Cochrane Library. REVIEW METHODS: Randomized controlled trials or pretest/posttest studies of adults with neurological diseases were included. The data included basic population characteristics, penetration-aspiration scores (PAS), peak expiratory flow rate (PEFR), cough volume acceleration (CVA) and maximum expiratory pressure (PEMax). RESULTS: Ten studies were included in this meta-analysis. Compared with the control groups, EMST in patients with neurological diseases significantly reduced the PAS (risk ratio (RR)=-0.94, 95% confidence interval (CI), 1.27--0.61, P<0.01) but did not increase the voluntary cough PEFR (RR=0.57, 95% CI, 0.62-1.77, P=0.35), CVA (RR=33.87, 95% CI, 57.11-124.85, P=0.47) or PEMax (RR=14.78, 95% CI, 16.98-46.54, P=0.36). CONCLUSION: EMST might improve swallowing function in patients with neurological diseases. However, conclusive evidence supporting the use of this approach in isolation for improving cough function is unavailable. Additional multicenter, randomized clinical trials performed using reliable and valid cough function outcome measures are required to explore the effects of EMST on cough function.

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