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1.
Biochim Biophys Acta Mol Basis Dis ; 1866(1): 165575, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31666206

RESUMO

Intervertebral disc degeneration (IVDD) is a well-known cause of lower back pain. Icariin has been shown to exert a protective effect on human nucleus pulposus (NP) cells and accordingly has implications for the prevention and treatment of IVDD; however, the molecular mechanisms underlying its action are not fully established. In this study, the mechanisms underlying its protection against hydrogen peroxide (H2O2)-induced oxidative stress injury were investigated. In vitro, we demonstrated that icariin inhibits H2O2-induced mitochondria-mediated apoptosis. It upregulates oxidative stress mediators, i.e., reactive oxygen species, and downregulates mitochondrial membrane potential. Nuclear factor erythroid 2-related factor 2 (Nrf-2) is a key factor involved in the regulation of the endogenous defense system. It was proved that icariin could activate the Nrf-2 signaling pathway, upregulate the protein expression of nuclear respiratory factor-1 and the mitochondrial transcription factor, promoting mitochondrial biogenesis in human NP cells. An Nrf-2 agonist and inhibitor promoted or partly abolished the protective effects of icariin on mitochondrial homeostasis. Moreover, it was demonstrated that the Nrf-2 signaling pathway could be inhibited by the phosphatidylinositol 3-Kinase/AKT pathway. In vivo, icariin ameliorated IVDD in a rat model by promoting Nrf-2 activity, and preserving extracellular matrix in NP cells. These data suggest that icariin could ameliorate IVDD in rat models in vivo. In summary, the protective effects of icariin on human NP cells may suppress the pathogenesis of IVDD via the Nrf-2 signaling pathway. Our findings suggest that the Nrf-2 signaling pathway is a novel therapeutic target for the treatment of IVDD.

2.
Support Care Cancer ; 28(1): 373-380, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31049672

RESUMO

BACKGROUND/OBJECTIVES: The assessment of nutritional status and the quality of life in patients with gastric cancer has become one of the important goals of current clinical treatment. The purpose of this study was to assess the nutritional status in hospitalized gastric cancer patients by using patient-generated subjective global assessment (PG-SGA) and to analyze the influence of nutritional status on the patients' quality of life (QOL). METHODS: We reviewed the pathological diagnosis of gastric cancer for 2322 hospitalized patients using PG-SGA to assess their nutritional status and collected data on clinical symptoms, the anthropometric parameters (height, weight, body mass index (BMI), mid-arm circumference (MAC), triceps skin-fold thickness (TSF), and hand-grip strength (HGS). We also collected laboratory data (prealbumin, albumin, hemoglobin) within 48 h after the patient was admitted to the hospital. The 30-item European Organization for Research and Treatment of Cancer Core Quality of Life Questionnaire (EORTC QLQ-C30) was used for QOL assessment in all patients. RESULTS: By using PG-SGA, we found 80.4% of the patients were malnourished (score ≥ 4) and 45.1% of the patients required urgent nutritional support (score ≥ 9). In univariate analysis, old age (> 65 years, p < 0.001), female (p = 0.007), residence in a village (p = 0.004), a lower level of education (p < 0.001), and self-paying (p < 0.001) were indicated as risk factors of patients with gastric cancer to be suffering from severe malnutrition. There was a negative correlation between PG-SGA and various nutritional parameters (p < 0.05). The quality of life was significantly different in gastric cancer patients with different nutritional status (p < 0.01). CONCLUSION: Malnutrition of hospitalized patients with gastric cancer in China is common and seriously affects the patients' quality of life. The nutritional status should be evaluated in a timely manner and reasonable nutritional intervention should be provided as soon as possible. The PG-SGA was fit for using as a clinical nutrition assessment method, being worthy of clinical application.

3.
Sci Total Environ ; 700: 134509, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31698269

RESUMO

Heavy metal concentrations in Taihu Lake sediment from studies performed between 2000 and 2018 were analyzed and Monte Carlo uncertainty analysis of heavy metal geo-accumulation, potential ecological risk and toxicity data for Taihu Lake sediment was performed to allow heavy metal pollution of Taihu Lake sediment to be described clearly, objectively, and comprehensively. Five main conclusions were drawn. (1) Most attention should be paid to As, Cd, Cr, Cu, Hg, Ni, Pb, and Zn pollution. (2) The geo-accumulation indices showed that Cd is the most important pollutant and that the probabilities of Taihu Lake sediment being moderately polluted, moderately-heavily polluted, and heavily polluted were found to be 53.6%, 34.9%, and 18.7%, respectively. (3) Cd is the main contributor to potential ecological risks and had cumulative low risk, moderate risk, and considerable risk probabilities of 63.0%, 27.0%, and 10.0%, respectively. (4) Toxicity unit evaluation results indicated that Pb is the main contributor of toxicity in Taihu Lake sediment and had cumulative low toxicity, moderate toxicity, and high toxicity probabilities of 53.0%, 36.8%, and 5.6%, respectively. (5) Positive matrix factorization model results indicated that industrial sources are the main suppliers of heavy metals to Taihu Lake sediment, contributing 64.9% of the heavy metals. The summarized results and conclusions will improve local government awareness of heavy metal pollution in Taihu Lake and will aid in the development of appropriate pollution control measures. The results will also provide reference data for future studies of heavy metal pollution in sediment from Taihu Lake and other lakes.

4.
Nat Chem ; 2019 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-31792388

RESUMO

Topological transitions between considerably different phases typically require harsh conditions to collectively break chemical bonds and overcome the stress caused to the original structure by altering its correlated bond environment. In this work we present a case system that can achieve rapid rearrangement of the whole lattice of a metal-organic framework through a domino alteration of the bond connectivity under mild conditions. The system transforms from a disordered metal-organic framework with low porosity to a highly porous and crystalline isomer within 40 s following activation (solvent exchange and desolvation), resulting in a substantial increase in surface area from 725 to 2,749 m2 g-1. Spectroscopic measurements show that this counter-intuitive lattice rearrangement involves a metastable intermediate that results from solvent removal on coordinatively unsaturated metal sites. This disordered-crystalline switch between two topological distinct metal-organic frameworks is shown to be reversible over four cycles through activation and reimmersion in polar solvents.

5.
FEBS Open Bio ; 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31788976

RESUMO

Long-term or heavy use of glucocorticoids (GC) can cause severe necrosis of the femoral head, but the underlying mechanisms are still unclear. Recent studies have found that mitochondrial dynamics play an important role in femoral head necrosis. Here, we investigated the effect of dexamethasone on the mitochondrial function of mesenchymal stem cells (MSCs). We observed that high concentrations of dexamethasone (10-6 mol/L) decreased cell activity, promoted apoptosis, elevated levels of reactive oxygen species (ROS), and disrupted mitochondrial dynamics. Furthermore, dexamethasone (10-6 mol/L) inhibited osteogenesis of stem cells and promoted adipogenesis. These findings may facilitate greater understanding of the adverse effects of dexamethasone on the femoral head.

6.
Clin Chim Acta ; 2019 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-31794768

RESUMO

BACKGROUND AND AIMS: The role of monocyte lymphocyte ratio (MLR) in predicting the risk of chronic kidney disease (CKD) is unclear, although inflammation contributes to the development of CKD. This study aimed to investigate whether elevated MLR predicts new-onset CKD. METHODS: This study enrolled 14033 consecutively Chinese participants. The primary outcome was the new-onset CKD defined as an estimated glomerular filtration rate < 60 mL/min/1.73 m2 or the presence of proteinuria after follow-up. After the descriptive analyses of baseline data, Univariate and multivariate Cox proportional models were used to evaluate the independent relationship between MLR and new-onset CKD. RESULTS: 11280 participants were included in the final analysis, and 58.44%(n=6592) of them were male. The mean age was 44.67 ± 12.85 years. After a median follow-up of 1.94 years, 2.55% (n=288) of participants developed new-onset CKD. MLR was associated with the increased risk of CKD (HR=16.12, 95% CI=4.52-57.56, p<0.0001). After adjustment for age, gender, body mass index, history of hypertension, systolic blood pressure, high-density lipoprotein cholesterol, triglyceride, fasting plasma glucose, uric acid and estimated glomerular filtration rate, MLR remained an independent risk factor for CKD (HR=8.89, 95%CI=2.18-36.27, p=0.0023). CONCLUSION: MLR is an independent predictor of the risk of CKD, which might be expected to better guide early prevention and treatment interventions.

7.
Int J Mol Sci ; 20(23)2019 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-31795097

RESUMO

Apple sugar and acid are the most important traits of apple fruit. Bud sport cultivars can provide abundant research materials for functional gene studies in apple. In this study, using bud sport materials with a rather different sugar and acid flavor, i.e., "Jonathan" and "Sweet Jonathan", we profiled the whole genome variations and transcriptional regulatory network during fruit developmental stages using whole genome sequencing and RNA-sequencing. Variation analysis identified 4,198,955 SNPs, 319,494 InDels, and 32,434 SVs between the two cultivars. In total, 4313 differentially expressed genes among all of the d 44,399 genes expressed were identified between the two cultivars during fruit development, and functional analysis revealed stress response and signal transduction related genes were enriched. Using 24,047 genes with a more variable expression value, we constructed 28 co-expression modules by weighted correlation network analysis. Deciphering of 14 co-expression modules associated with sugar or acid accumulation during fruit development revealed the hub genes associated with sugar and acid metabolism, e.g., MdDSP4, MdINVE, and MdSTP7. Furthermore, exploration of the intra network of the co-expression module indicated the close relationship between sugar and acid metabolism or sugar and stress. Motif-based sequence analysis of the 17 differentially expressed ATP-binding cassette transporter genes and Yeast one-hybrid assay identified and confirmed a transcription factor, MdBPC6, regulating the ATP-binding cassette (ABC) transporter genes and potentially participating in the apple fruit development or stress response. Collectively, all of the results demonstrated the use of parallel bud mutation sequencing and identified hub genes, and inferred regulatory relationships providing new information about apple fruit sugar and acid accumulation or stress response.

8.
BMC Ecol ; 19(1): 50, 2019 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-31801501

RESUMO

BACKGROUND: Stellera chamaejasme L. is a poisonous plant widely distributes in degraded grasslands in China. The mechanism underlying its spread remains unknown. In some degraded grasslands, S. chamaejasme has gradually replaced previous dominant species, such as Leymus chinensis, Stipa krylovii, Artemisia eriopoda on typical steppes. Apart from its unpalatability by livestock, we hypothesized that the survival strategy (nutrient uptake and water use efficiency) of S. chamaejasme in degraded grasslands could be distinct from other coexisting species in the community. Recently, ecological stoichiometry has been suggested as a new approach for studying the demand for natural resources of plants in a changing world, and the leaf carbon isotopic composition (δ13C leaf) as a rapid and effective high throughput phenotyping method for water use efficiency (WUE), both of which can reveal the survival and adaptive strategies of plants. Therefore, in this study we aimed to fill the knowledge gap concerning ecological stoichiometry in the leaf, stem, and root of S. chamaejasme and its surrounding soil on grasslands with different degrees of degradation, and comparing the leaf nutrient content and δ13C of S. chamaejasme with the coexisting species (L. chinensis, S. krylovii, A. eriopoda) in the communities. Toward this goal, we conducted a field survey in which plants and soils were sampled from four different degraded grasslands on typical steppes in China. RESULTS: Our results showed that there is no significant difference of carbon content (C%) and nitrogen content (N%) in leaves of S. chamaejasme in different degraded grasslands, and all element contents and element ratios in stems did not differ significantly. Meanwhile, ecological stoichiometry of S. chamaejasme is distinct from the coexisting species, with low C%, high N% and phosphorus content (P%) in the leaf, indicating high nutrient uptake efficiency of S. chamaejasme in nutrient-poor environments like degraded grasslands. Additionally, S. chamaejasme showed significant higher WUE than other species. CONCLUSIONS: Our results indicated that high nutrient uptake efficiency and high WUE of S. chamaejasme might together contribute to the spread of S. chamaejasme in degraded grasslands.

9.
Nucleic Acids Res ; 2019 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-31701131

RESUMO

Comprehensive genomic analyses of cancers have revealed substantial intrapatient molecular heterogeneities that may explain some instances of drug resistance and treatment failures. Examination of the clonal composition of an individual tumor and its evolution through disease progression and treatment may enable identification of precise therapeutic targets for drug design. Multi-region and single-cell sequencing are powerful tools that can be used to capture intratumor heterogeneity. Here, we present a database we've named CancerTracer (http://cailab.labshare.cn/cancertracer): a manually curated database designed to track and characterize the evolutionary trajectories of tumor growth in individual patients. We collected over 6000 tumor samples from 1548 patients corresponding to 45 different types of cancer. Patient-specific tumor phylogenetic trees were constructed based on somatic mutations or copy number alterations identified in multiple biopsies. Using the structured heterogeneity data, researchers can identify common driver events shared by all tumor regions, and the heterogeneous somatic events present in different regions of a tumor of interest. The database can also be used to investigate the phylogenetic relationships between primary and metastatic tumors. It is our hope that CancerTracer will significantly improve our understanding of the evolutionary histories of tumors, and may facilitate the identification of predictive biomarkers for personalized cancer therapies.

10.
Int J Biol Macromol ; 2019 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-31726147

RESUMO

Gleditsia triacanthos polysaccharide, known as galactomannan, has not been exploited as a new functional material even though it possesses industrial potential in food and biomedicine. Galactomannans were recovered from the endosperm of seeds (15 weeks to 25 weeks after flowering) for deposition and maturation analysis. These galactomannans were characterized by using Nuclear magnetic resonance (NMR), X-ray diffraction (XRD), and monosaccharide composition analysis (particularly the mannose to galactose ratio) and molecular weight, solubility, and rheological measurements. The ratio of the three parts in mature seeds was as follows: endosperm (36.67%), hull (34.41%), and embryo (28.92%). The M/G ratio increased from 2.53 to 3.24 between 15 and 23 weeks and then decreased to 3.16 in 25 weeks, consistent with the trends of rheology and solubility. The molecular weight (1.28 × 106 g/mol) and intrinsic viscosity (882.53 mL/g) reached the maximum at 23 weeks and then decreased. Additionally, NMR and XRD showed that the M/G ratio did not change the basic chemical structure but caused slight changes in crystallinity. The purpose of the study was to reveal the changes in galactomannan structure, rheology, and solubility during G. triacanthos galactomannan deposition and maturation to facilitate exploration of its potential industrial applications.

11.
Ultrason Sonochem ; 61: 104834, 2019 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-31678867

RESUMO

Managing environmental contamination with Benz[a]anthracene (B[a]A) is essential due to its carcinogenic, teratogenic and mutagenic effects on humans and the environment. At present, the mainly B[a]A degradation methods used are photodegradation, bioremediation and traditional advanced oxidation, although they all have disadvantages. In this study, B[a]A was degraded by hydrodynamic cavitation (HC), chlorine dioxide (ClO2), or an innovative combination of the two methods. According to high performance liquid chromatography (HPLC) and gas chromatography-mass spectrometry (GC-MS) analysed the degradation products and degradation pathway of B[a]A, with the kinetics of different degradation methods discussed. Under optimal conditions, HC combined with ClO2 oxidation can further degrade products to achieve ring cleavage. Compared with the two separate degradation process methods, the combined method exerts a synergistic effect on the degradation of B[a]A, with an enhancement factor of 1.48. Experimental results showed that the combination method can realize enhanced complete degradation of B[a]A, reduce ClO2 requirements, improve efficiency, reduce energy consumption and produce less harmful products with ring cleavage achieved.

12.
Nat Commun ; 10(1): 5132, 2019 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-31723129

RESUMO

The Arabidopsis EH proteins (AtEH1/Pan1 and AtEH2/Pan1) are components of the endocytic TPLATE complex (TPC) which is essential for endocytosis. Both proteins are homologues of the yeast ARP2/3 complex activator, Pan1p. Here, we show that these proteins are also involved in actin cytoskeleton regulated autophagy. Both AtEH/Pan1 proteins localise to the plasma membrane and autophagosomes. Upon induction of autophagy, AtEH/Pan1 proteins recruit TPC and AP-2 subunits, clathrin, actin and ARP2/3 proteins to autophagosomes. Increased expression of AtEH/Pan1 proteins boosts autophagosome formation, suggesting independent and redundant pathways for actin-mediated autophagy in plants. Moreover, AtEHs/Pan1-regulated autophagosomes associate with ER-PM contact sites (EPCS) where AtEH1/Pan1 interacts with VAP27-1. Knock-down expression of either AtEH1/Pan1 or VAP27-1 makes plants more susceptible to nutrient depleted conditions, indicating that the autophagy pathway is perturbed. In conclusion, we identify the existence of an autophagy-dependent pathway in plants to degrade endocytic components, starting at the EPCS through the interaction among AtEH/Pan1, actin cytoskeleton and the EPCS resident protein VAP27-1.

13.
Eur J Pharmacol ; : 172787, 2019 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-31712061

RESUMO

Zinc finger E-box binding homeobox 1 (ZEB1) (previously known as TCF8), a transcriptional repressor, is a member of the zinc-finger family of proteins. Numerous studies have demonstrated that abnormal expression of ZEB1 in many types of liver disease including hepatocellular carcinoma (HCC). Liver fibrosis is the basis and central link in the progression of liver disease. Thereby, the function of ZEB1 in liver fibrosis has been investigated. The aim of the present study was to investigate the role of ZEB1 in liver fibrosis and to elucidate the mechanism. In this study, we explored the effect of ZEB1 in hepatic stellate cells (HSCs) activation and the regulatory mechanism of the Wnt/ß-catenin signaling pathway. Additionally, ZEB1 positively regulated the expression levels of α-SMA and Col.I in vivo and in vitro, which were correlated with the activated HSCs. Furthermore, overexpression of ZEB1 could inhibit HSCs apoptosis and promote IL-6 and TNF-α secretion in LX-2 cells. Conversely, ZEB1 silencing led to the promotion of cell proliferation and the reduction of IL-6 and TNF-α secretion in LX-2 cells. Mechanically, canonical Wnt/ß-catenin signaling pathway could be regulated by ZEB1. Collectively, the data suggested that ZEB1 might play a significant role in the activation of LX-2 cells, and Wnt/ß-catenin signaling pathway might participate in this progression.

14.
Environ Health ; 18(1): 96, 2019 11 14.
Artigo em Inglês | MEDLINE | ID: mdl-31727105

RESUMO

BACKGROUND: The associations between maternal exposure to ambient PM2.5 during pregnancy and the risk of premature rupture of membranes (PROM) and preterm premature rupture of membranes (PPROM) are controversial. And no relevant study has been conducted in Asia. This study aimed to determine the association between maternal exposure to ambient PM2.5 during pregnancy and the risk of (P)PROM. METHODS: A cohort study including all singleton births in a hospital located in Central China from January 2015 through December 2017 was conducted. Multivariable logistic regression models, stratified analysis, generalized additive model, and two-piece-wise linear regression were conducted to evaluate how exposure to ambient PM2.5 during pregnancy is associated with the risks of PROM and PPROM. RESULTS: A total of 4364 participants were included in the final analysis, where 11.71 and 2.34% of births were complicated by PROM and PPROM, respectively. The level of PM2.5 exhibited a degree of seasonal variation, and its median concentrations were 63.7, 59.3, 55.8, and 61.8 µg/m3 for the first trimester, second trimester, third trimester, and the whole duration of pregnancy, respectively. After adjustment for potential confounders, PROM was positively associated with PM2.5 exposure (per 10 µg/m3) [Odds Ratio (OR) = 1.14, 95% Confidence Interval (CI), 1.02-1.26 for the first trimester; OR = 1.09, 95% CI, 1.00-1.18 for the second trimester; OR = 1.13, 95% CI, 1.03-1.24 for the third trimester; OR = 1.35, 95% CI, 1.12-1.63 for the whole pregnancy]. PPROM had positive relationship with PM2.5 exposure (per 10 µg/m3) (OR = 1.17, 95% CI, 0.94-1.45 for first trimester; OR = 1.11, 95% CI, 0.92-1.33 for second trimester; OR = 1.19, 95% CI, 0.99-1.44 for third trimester; OR = 1.53, 95% CI, 1.03-2.27 for the whole pregnancy) Positive trends between the acute exposure window (mean concentration of PM2.5 in the last week and day of pregnancy) and risks of PROM and PPROM were also observed. CONCLUSIONS: Exposure to ambient PM2.5 during pregnancy was associated with the risk of PROM and PPROM.

15.
Artigo em Inglês | MEDLINE | ID: mdl-31780309

RESUMO

Hydrogen sulfide shows great importance in various physiological and biochemical processes. The development of fluorescence probes for facile and efficient detection of H2S has attracted increasing attention of researchers. Herein, we synthesized two fluorescence probes based on simple naphthalene structure for detection of H2S. Upon reaction with H2S, the probe DN-DM exhibited a red fluorescence emission with large Stokes shift. The probe showed high sensitivity, pH insensitivity and good selectivity for H2S over other analytes including common biothiols. The detection mechanism was based on the thiolysis of the dinitrophenyl ether moiety, which was confirmed by 1H NMR spectral analysis. The DFT calculation was also performed for a deeper understanding of the photophysical properties. In addition, these probes showed good cell-membrane permeability and could be utilized for detection of H2S in living cells.

16.
Biosens Bioelectron ; : 111883, 2019 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-31767349

RESUMO

Nanozymes with peroxidase-like activity have been widely used as signal labels in electrochemical immunosensors. However, these sensors always suffer from some shortcomings during the processes underlying nanozyme labeling, including complex reactions, nanozyme inactivation after being decorated on the antibodies. To solve these problems, a novel electrochemical immunosensor was designed for ultrasensitive detection of sulfonamides (SAs), in which the synthesized 2D Cu-TCPP(Fe) with peroxidase-like property was used as a nanozyme that was directly modified on the electrode surface. Meanwhile, the structure of 2D Cu-TCPP(Fe) could be destroyed by the polyethyleneimine (PEI) from PEI-GO@Ab2 due to the stronger affinity between PEI and Cu2+, leading to an activity change of the prepared nanozyme. When H2O2 was introduced to the system, the electrochemical current was significantly declined owing to the peroxidase activity of 2D Cu-TCPP(Fe) decreased, which led to signal amplifications. Under the optimized conditions, this strategy had a wide detection range (1.186-28.051 ng/mL), satisfactory accuracy and precision (recoveries, 64-118%; CV, 2.16-7.27%) with a low detection limit of 0.395 ng/mL. The findings of this study indicate that the electrochemical immunosensor we developed has great potential and can be used for enzyme-free detection of SAs in environmental samples.

17.
Eur J Radiol ; 121: 108711, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31677544

RESUMO

PURPOSE: We developed and validated a radiomic model based on mammography and assessed its value for predicting the pathological diagnosis of Breast Imaging Reporting and Data System (BI-RADS) category 4 calcifications. MATERIALS AND METHODS: Patients with a total of 212 eligible calcifications were recruited (159 cases in the primary cohort and 53 cases in the validation cohort). In total, 8286 radiomic features were extracted from the craniocaudal (CC) and mediolateral oblique (MLO) images. Machine learning was used to select features and build a radiomic signature. The clinical risk factors were selected from the independent clinical factors through logistic regression analyses. The radiomic nomogram incorporated the radiomic signature and an independent clinical risk factor. The diagnostic performance of the radiomic model and the radiologists' empirical prediction model was evaluated by the area under the receiver operating characteristic curve (AUC). The differences between the various AUCs were compared with DeLong's test. RESULTS: Six radiomic features and the menopausal state were included in the radiomic nomogram, which discriminated benign calcifications from malignant calcifications with an AUC of 0.80 in the validation cohort. The difference between the classification results of the radiomic nomogram and that of radiologists was significant (p < 0.05). Particularly for patients with calcifications that are negative on ultrasounds but can be detected by mammography (MG+/US- calcifications), the identification ability of the radiomic nomogram was very strong. CONCLUSIONS: The mammography-based radiomic nomogram is a potential tool to distinguish benign calcifications from malignant calcifications.

18.
Langmuir ; 2019 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-31714092

RESUMO

The investigation of the response kinetics of smart colloidal microgel films is crucial for their optimization to enable advanced applications. We study the classical thermoresponsive microgel model system N-isopropylacrylamide cross-linked with N,N'-methylenebisacrylamide. Without the typically used polyelectrolyte coating of the substrate, thin microgel films are prepared in a single spin-coating step. Atomic force microscopy measurements reveal an extremely dense packing, resulting in a homogeneous compact thin film of microgel particles. The hydration kinetics of these films in H2O and D2O atmospheres as well as the kinetics of the solvent exchange between both water species are investigated with in situ time-of-flight neutron reflectometry (TOF-NR) and in situ Fourier-transform infrared (FTIR) spectroscopy. With accounting for a nonconstant humid atmosphere, the intrinsic diffusion dynamics of water molecules into the thin microgel film are modeled and the specific time constant τ and the effective Flory-Huggins interaction parameter χeff are determined. Comparing the results in H2O and D2O atmospheres, TOF-NR and FTIR spectroscopy results show an increased affinity of the microgel films toward H2O as compared to D2O. From the FTIR spectroscopy data, we further identify different kinetics of intermolecular processes and order them according to their temporal evolution.

19.
Artigo em Inglês | MEDLINE | ID: mdl-31773939

RESUMO

Remodeling of cellular surfaces is shown highly effective in manipulation and control of cell behaviors via non-biological means. By 5-thio-2-nitrobenzoate (TNB)-mediated, fast, and reversible disul-fide-thiol exchange, a sequential layer by layer assembly process was developed to grow albumin pro-tein shells on cellular surfaces fixed by disulfide-linked network, in a cytocompatible manner. The artificial shells, accomplished by a double-assembly process, were sustainable up to > 1 day, and there-after gradually bio-absorbed with unaffected cell viability. The surface engineering process enabled dynamically remodeling of cellular surfaces that effectively controlled cell behaviors including regulated cell proliferation, enhanced uptake efficiency of dextran-FITC that is known for cell-impermeability, and targeted imaging. This unique approach was well validated on tumor cell (B16), immune cell (DC2.4) and neutrophils showing its potential universality for most of the cells that are rich in thiols. The new strategy will show promise in cell manipulation and targeted imaging.

20.
Artigo em Inglês | MEDLINE | ID: mdl-31705175

RESUMO

PURPOSE: Accurate evaluation of hypoxia is particularly important in patients with nasopharyngeal carcinoma (NPC) undergoing radiotherapy. The aim of this study was to propose a novel imaging strategy for quantitative three-dimensional (3D) evaluation of hypoxia in a small animal model of NPC. METHODS: A carbonic anhydrase IX (CAIX)-specific molecular probe (CAIX-800) was developed for imaging of hypoxia. Mouse models of subcutaneous, orthotopic, and spontaneous lymph node metastasis from NPC (5 mice per group) were established to assess the imaging strategy. A multi-modality imaging method that consisted of a hybrid combination of fluorescence molecular tomography-computed tomography (FMT-CT) and multispectral optoacoustic tomography (MSOT) was used for 3D quantitative evaluation of tumour hypoxia. Magnetic resonance imaging, histological examination, and immunohistochemical analysis were used as references for comparison and validation. RESULTS: In the early stage of NPC (2 weeks after implantation), FMT-CT enabled precise 3D localisation of the hypoxia biomarker with high sensitivity. At the advanced stage (6 weeks after implantation), MSOT allowed multispectral analysis of the biomarker and haemoglobin molecules with high resolution. The combination of high sensitivity and high resolution from FMT-CT and MSOT could not only detect hypoxia in small-sized NPCs but also visualise the heterogeneity of hypoxia in 3D. CONCLUSIONS: Integration of FMT-CT and MSOT could allow comprehensive and quantifiable evaluation of hypoxia in NPC. These findings may potentially benefit patients with NPC undergoing radiotherapy in the future. Graphical abstract A novel multimodality imaging strategy for three-dimensional evaluation of tumour hypoxia in an orthotopic model of nasopharyngeal carcinoma.

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