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1.
J Appl Microbiol ; 2020 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-32162449

RESUMO

AIMS: The purpose of this study was to investigate the characteristics of gut microbiota of children with obesity in Harbin, China and to screen anti-obesity strains in vitro and in vivo. METHODS AND RESULTS: The gut microbiota of children with obesity and normal-weight children were investigated by high-throughput sequencing, and based on the different composition in gut microbiota, the strains with potential anti-obesity properties were screened in vitro and in vivo. Compared with normal-weight children, the Firmicutes to Bacteroidetes ratio in children with obesity decreased. Moreover, the relative abundances of Lactobacillus and Bifidobacterium in children with obesity were decreased, while the relative abundance of Akkermansia increased. After a series of screening in vitro and in vivo, nine strains were found inhibiting the body weight gain of HFD-fed mice, of which two strains showed significant effects (P<0.05). CONCLUSIONS: There were significant changes in gut microbiota of children with obesity from Harbin, China. The obtained strains showed obvious anti-obesity effects, and the screening methods used in this study were effective. SIGNIFICANCE AND IMPACT OF STUDY: This study enriched the research results on the characteristics of gut microbiota of children with obesity in different regions of the world. Moreover, we established a new and effective method for screening anti-obesity strains, and obtained effective strains.

2.
Spectrochim Acta A Mol Biomol Spectrosc ; 234: 118248, 2020 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-32179466

RESUMO

Silver ions, as a commonly used industrial heavy metal, tends to deposit in the body and induce many diseases. In this work, modified CdTe QDs with green and red emission were synthesized to assemble dual-QDs, which could be efficient and selective utilized for Ag+ determination through the electron transfer progress between surface functional group of dual-QDs and Ag+, and the aggregation of Ag+ on the surface of dual-QDs. Under the appropriate pH value and volume ratio, the interaction between the surface functional groups of assembled dual-QDs reduce the affinity of Hg2+ in this system. The fluorescent signal of dual-QDs simultaneously attenuation or enhancement in the same proportion remove the interference of Cu2+ and other metal ions. Therefore, this method can selectively detect Ag+ without any masking agents. The linear region of detection was from 0 to 800 nmol/L (R2 > 0.998), and low of detection (LOD) was 7.7 nmol/L, which could meet the corresponding standards of World Health Organization (WHO) and Environmental Protection Agency (EPA). This effective proposed dual-QDs ratios fluorescent probe has been applied to detect Ag+ in real environment water, tea and Citri Reticulatae Pericarpium (CRP) water.

3.
Cancer Med ; 9(6): 2243-2251, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31994324

RESUMO

PURPOSE: The proportion of cured gastric cancer patients has drawn the attention of patients, physicians, and healthcare providers after comprehensive prevention and control measures were carried out for several years. Therefore, the relative survival and cure fraction were estimated in our study. METHODS: Population-based cancer registration data were used to estimate survival and cure fraction. A total of 7585 gastric cancer cases (ICD10:C16.0 ~ C16.9) were extracted and included in the final analysis. Cases were diagnosed in 2003-2012 and followed until the end of 2017. Relative survival was calculated as the ratio between the observed survival through the life-table method. The expected survival was estimated by the Ederer II method. The cure fraction was estimated using flexible parametric cure models stratified by age and calendar period when the cases were diagnosed. RESULTS: The 5-year relative survival of cardia gastric cancer increased with the calendar period of 2003-2004, 2005-2006, 2007-2008, 2009-2010, and 2011-2012 (27.5%, 28.3%, 33.5%, 38.2%, and 46.8%, respectively). The increasing trend along with the calendar periods was also observed in cure proportion of cardia gastric cancer (24.8%, 25.2%, 31.7%, 36.0%, and 43.1%, respectively). Notable improvement of cure proportion was observed in the period of 2011-2012, compared with the initial period of 2003-2004. There was an improvement of 79.8% among all gastric cancer subjects, and it was 74.1% and 55.7% in cardia gastric and noncardia gastric cancer subjects, respectively. The median survival of "uncured" patients showed no significant improvement along with the calendar periods in all age groups. CONCLUSIONS: Notable improvement of gastric cancer relative survival and cure proportion was observed in Linzhou during 2003-2012.

4.
Spectrochim Acta A Mol Biomol Spectrosc ; 227: 117683, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31685422

RESUMO

Colorimetric sensor array is a sensitive, rapid, and inexpensive detection technology which simulates human olfaction system based on various organic dyes. In this work, a sensor array based on acid-sensitive CdTe QDs coupled with chemometrics method was developed and proved to be a rapid, accurate and sensitive method for identification of 32 kinds of Chinese traditional cereal vinegars (CTCV). The specificity of identification of this method was mainly depends on the organic acids and melanoidins of CTCV. Among them, organic acids can quench the fluorescence of QDs through enhancing their electron transfer (hydrogen bond) and resonance energy transfer, and the fluorescence intensity of melanoidin was closely related to the brewing technology and aging year of CTCV. The types and aging time of 32 CTCV can be 100% identified at a dilution of 1000 by partial least squares discriminant analysis, when the latent variables were 4. And only one kind of QDs is needed instead of various organic dyes to this kind of colorimetric sensor array. Except for vinegar, this method can also be used in the identification of other food which rich in organic acid.

5.
Plants (Basel) ; 8(11)2019 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-31717304

RESUMO

Plant cells undergo massive orderly changes in structure, biochemistry, and gene expression during cell senescence. These changes cannot be distinguished from the hydrolysis/degradation function controlled by the ubiquitination pathway, autophagy, and various hydrolases in cells. In this mini-review, we summarized current research progress that the human HECT (homologous to the E6AP carboxyl terminus)-type ubiquitin E3 ligases have non-redundant functions in regulating specific signaling pathways, involved in a number of human diseases, especially aging-related diseases, through the influence of DNA repair, protein stability, and removal efficiency of damaged proteins or organelles. We further compared HECT E3 ligases' structure and functions between plant and mammalian cells, and speculated new aspects acting as degrading signals and regulating signals of HECT E3 ligase in cell senescence and the cell death of plants.

6.
PeerJ ; 7: e7812, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31592178

RESUMO

Objectives: To compare the efficacy of trans-oral robotic surgery (TORS) with that of coblation assisted tongue base reduction surgery in patients with obstructive sleep apnea syndrome (OSAS). Subjects and Methods: The medical charts were retrospectively reviewed for all OSAS patients admitted to one institution for surgical intervention between 2012 and 2017. We analyzed 33 cases; 16 patients received TORS and 17 received coblation surgery for tongue base reduction. Both groups received concomitant uvulopalatoplasty. Surgical outcomes were evaluated by comparing the initial polysomnography (PSG) parameters with the follow-up PSG data (at least 3 months after the surgery). Epworth sleepiness scale (ESS) and complications were also compared between the 2 groups. Results: The success rate (≥50% reduction of pre-operative AHI and post-operative AHI <20) in the TORS group and coblation group were 50% and 58%, respectively, and there was no significant difference (p = .611). The AHI (mean ± SD) reduction in the TORS and coblation groups were 24.9 ± 26.5 events/h and 19.4 ± 24.8 events/h, respectively; the between-group difference was not significant (p = .631). ESS improvement did not differ significantly between the TORS and coblation groups (3.8 ± 6.6 and 3.1 ± 9.2, respectively, p = .873). The rates of minor complication were higher in the TORS group (50%) than that of the coblation group (35.3%) without statistical significance (p = .393). Conclusion: TORS achieved comparable surgical outcomes compared to coblation assisted tongue base reduction surgery in OSAS patients. Multilevel surgery using either TORS or coblation tongue base reduction combined with uvulopalatoplasty is an effective approach for the management of OSAS.

7.
Biochem Biophys Res Commun ; 519(2): 316-322, 2019 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-31506175

RESUMO

Tilianin (TIL) may prevent and treat myocardial ischemia reperfusion injuries. However, its oral administration is hampered by its low bioavailability. The present study aimed to formulate lipid-polymer hybrid nanoparticles (LPHNs) as carriers for the sustained release and oral bioavailability enhancement of TIL in vitro and in vivo. A nanodrug delivery system of TIL-loaded LPHNs (TIL-LPHNs) was constructed. TIL-LPHNs were prepared via a self-assembly method, and their particle size, polymer dispersity index (PDI), zeta potential, encapsulation efficiency (EE) and morphology were investigated. In addition, pharmacokinetic studies were performed in vivo. The TIL-LPHN formulation produced a spherical, homogeneous, smooth surface and multi-lamellar structured nanoparticles. The particle size and distribution profile of TIL-LPHNs had a mean particle diameter of 54.6 ±â€¯5.3 nm and PDI of 0.112 ±â€¯0.017. The zeta potential was -33.4 ±â€¯4.7 mV. The EE of TIL-LPHNs was 86.6 ±â€¯3.6%, which was determined with the dialysis method. The TIL-LPHNs significantly enhanced the oral bioavailability of TIL with a 3.7-fold increase in the area under the concentration-time curve in comparison with the TIL solution. These findings support the potential use of LPHNs in improving the stability and bioavailability of TIL via oral administration.

8.
Artigo em Inglês | MEDLINE | ID: mdl-31443046

RESUMO

The dysregulation and mutation of long non-coding RNAs (lncRNAs) have been proved to result in a variety of human diseases. Identifying potential disease-related lncRNAs may benefit disease diagnosis, treatment and prognosis. A number of methods have been proposed to predict the potential lncRNA-disease relationships. However, most of them may give rise to incorrect results due to relying on single similarity measure. This article proposes a novel framework (ILDMSF) by fusing the lncRNA similarities and disease similarities, which are measured by lncRNA-related gene and known lncRNA-disease interaction and disease semantic interaction, and known lncRNA-disease interaction, respectively. Further, the support vector machine is employed to identify the potential lncRNA-disease associations based on the integrated similarity. The leave-one-out cross validation is performed to compare ILDMSF with other state of the art methods. The experimental results demonstrate our method is prospective in exploring potential correlations between lncRNA and disease.

9.
Comput Methods Programs Biomed ; 177: 175-182, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31319946

RESUMO

BACKGROUND AND OBJECTIVE: In the United States, lung cancer is the leading cause of cancer death. The survival rate could increase by early detection. In recent years, the endobronchial ultrasonography (EBUS) images have been utilized to differentiate between benign and malignant lesions and guide transbronchial needle aspiration because it is real-time, radiation-free and has better performance. However, the diagnosis depends on the subjective judgment from doctors. In some previous studies, which using the grayscale image textures of the EBUS images to classify the lung lesions but it belonged to semi-automated system which still need the experts to select a part of the lesion first. Therefore, the main purpose of this study was to achieve full automation assistance by using convolution neural network. METHODS: First of all, the EBUS images resized to the input size of convolution neural network (CNN). And then, the training data were rotated and flipped. The parameters of the model trained with ImageNet previously were transferred to the CaffeNet used to classify the lung lesions. And then, the parameter of the CaffeNet was optimized by the EBUS training data. The features with 4096 dimension were extracted from the 7th fully connected layer and the support vector machine (SVM) was utilized to differentiate benign and malignant. This study was validated with 164 cases including 56 benign and 108 malignant. RESULTS: According to the experiment results, applying the classification by the features from the CNN with transfer learning had better performance than the conventional method with gray level co-occurrence matrix (GLCM) features. The accuracy, sensitivity, specificity, and the area under ROC achieved 85.4% (140/164), 87.0% (94/108), 82.1% (46/56), and 0.8705, respectively. CONCLUSIONS: From the experiment results, it has potential ability to diagnose EBUS images with CNN.


Assuntos
Brônquios/diagnóstico por imagem , Diagnóstico por Computador , Neoplasias Pulmonares/diagnóstico por imagem , Pulmão/diagnóstico por imagem , Ultrassonografia , Adulto , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Área Sob a Curva , Humanos , Pessoa de Meia-Idade , Reconhecimento Automatizado de Padrão , Curva ROC , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Adulto Jovem
10.
Psychooncology ; 28(9): 1836-1844, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31240803

RESUMO

OBJECTIVE: The impact of participating in breast cancer screening programmes on health-related quality of life (HRQoL)is poorly understood. METHODS: Based on a national breast cancer screening programme in China, a multicentre cross-sectional survey was conducted covering 12 provinces from September 2013 to December 2014. HRQoL of participants in the screening population and general population was evaluated by the three-levelEuroQol-five-Dimensions (EQ-5D-3L) instrument, and utility scores were generated through the Chinese value set. Univariate and multivariate regression analyses were performed to explore determinants of utility scores and anxiety/depression problems. RESULTS: For screening group and general population (n = 4756, mean age = 51.6 year old), the corresponding utility scores were 0.937 (95% CI, 0.933-0.941) and 0.953 (0.949-0.957) (P < .001). Pain/discomfort and anxiety/depression were the most common reported in both groups (51.4% and 34.3%, P < .001). Utility scores at prescreening, in-screening, and postscreening interview timings were 0.928 (0.921-0.935), 0.958 (0.948-0.969), and 0.938 (0.933-0.943), respectively (P < .001); the corresponding proportions of anxiety/depression reporting were 25.9%, 16.3%, and 21.1%, respectively (P = .004). Interview timing, geographical region, and insurance status were associated with HRQoL and anxiety/depression in women at high-risk of breast cancer. CONCLUSIONS: Utility scores of screening participants were significantly lower than that of general population in China, but the difference may be clinically insignificant. Further cohort studies using HRQoL measurements are needed.

11.
Int J Ophthalmol ; 12(6): 883-891, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31236341

RESUMO

AIM: To investigate the effects of spectral composition and light intensity on natural refractive development in guinea pigs. METHODS: A total of 124 pigmented guinea pigs (2-week-old) were randomly assigned to three groups at high (Hi; 4000 lx), medium (Me; 400 lx) and low (Lo; 50 lx) light intensities under a 12:12 light/dark cycle for 6wk. Each group was subdivided into subgroups with the following spectra: broad spectrum Solux halogen light (BS), 600 nm above-filtered continuous spectrum (600F), 530 nm above-filtered continuous spectrum (530F), and 480 nm above-filtered continuous spectrum (480F; HiBS: n=10, Hi600F: n=10, Hi530F: n=10, Hi480F: n=10, MeBS: n=10, Me600F: n=10, Me530F: n=10, Me480F: n=10, LoBS: n=11, Lo600F: n=12, Lo530F: n=10, Lo480F: n=11). Refractive error, corneal curvature radius, and axial dimensions were determined by cycloplegic retinoscopy, photokeratometry, and A-scan ultrasonography before and after 2, 4, and 6wk of treatment. Average changes from both eyes in the ocular parameters and refractive error were compared among different subgroups. RESULTS: After 6wk of exposure, high-intensity lighting enhanced hyperopic shift; medium- and low-intensity lighting enhanced myopic shift (P<0.05). Under the same spectrum, axial increase was larger in the low light intensity group than in the medium and high light intensity groups (HiBS: 0.65±0.02 mm, MeBS: 0.67±0.01 mm, LoBS: 0.82±0.02 mm; Hi600F: 0.64±0.02 mm, Me600F: 0.67±0.01 mm, Lo600F: 0.81±0.01 mm; Hi530F: 0.64±0.02 mm, Me530F: 0.67±0.01 mm, Lo530F: 0.73±0.02 mm; Hi480F: 0.64±0.01 mm, Me480F: 0.66±0.01 mm, Lo480F: 0.72±0.02 mm; P<0.05). Under 400 lx, there was a faster axial increase in the MeBS group than in the Me480F group (P<0.05). Under 50 lx, axial length changes were significantly larger in LoBS and Lo600F than in Lo530F and Lo480F (P<0.01). CONCLUSION: Under high-intensity lighting, high light intensity rather than spectrum distributions that inhibits axial increase. Under medium- and low-intensity lighting, filtering out the long wavelength inhibits axial growth in juvenile guinea pigs.

12.
Stem Cells Int ; 2019: 8404168, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31249601

RESUMO

Stem cell therapies for intervertebral disc degeneration have been demonstrated as a promising strategy. Previous studies have shown that human nucleus pulposus cell- (NPC-) derived exosomes can induce the differentiation of mesenchymal stem cells (MSCs) into NP-like cells in vitro. However, the mechanism of MSC differentiation into NP-like cells with the induction of NPC exosomes is still unclear. Here, we verified the induction effects of NPC exosomes on the differentiation of MSCs into NP-like cells. In addition, the Notch1 pathway was downregulated in this process. Then, DAPT and soluble Jagged1 (SJAG) were applied to inhibit or enhance the expression of the Notch1 pathway, respectively, resulting in the upregulation or downregulation of collagen II, aggrecan, and Sox9 in MSCs. Knocking down of Notch1 protein facilitated the effects of NPC exosomes on the differentiation of MSCs into NP-like cells. NPC exosomes were more effective than an indirect coculture system in terms of the differentiation of MSCs into NP-like cells. Inhibition of NPC exosome secretion with Rab27a siRNA prevented the induction effects of an indirect coculture system on the differentiation of MSCs into NP-like cells. Transwell migration assays revealed that NPC exosomes could promote the migration of MSCs. Taken together, the Notch1 pathway was negatively associated with the differentiation of MSCs into NP-like cells with the treatments of NPC exosomes. Inhibition of the Notch1 pathway facilitates NPC exosome-induced differentiation of MSCs into NP-like cells in vitro. NPC exosomes play a key role in the differentiation of MSCs into NP-like cells in an indirect coculture system of NPCs and MSCs.

13.
Anal Bioanal Chem ; 411(18): 4221-4229, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31143966

RESUMO

Herein, rare-earth europium doped in Gd2O3@SiO2-based molecularly imprinted polymer (MIP) composite nanospheres with a multilayer core-shell structure was successfully prepared via a facile and versatile layer-by-layer assembly strategy of combination with sol-gel, hydrothermal, and surface imprinting procedure. The rare-earth Gd2O3:Eu3+ was embedded into the inner portion of the imprinted polymer which was well-suited for fluorescent monitoring carbaryl selectively. Results showed that the recognition process of the nanosensor for carbaryl was fast and reached dynamic equilibrium at ca. 20 min. The fluorescence intensity (F0/F) is linearly related to the concentration of carbaryl [Q] within the range of 16-80 µg mL-1, and the linear equation is F0/F = 0.8909 - 9.775 × 10-4[Q] (R = 0.9963) with 10 µg mL-1 as the detection limit. Competition experiments showed that other analogues (methomyl, aldicarb, and isoprocarb) have nearly no interference in the detection of carbaryl. Moreover, this MIP nanosensor was successfully applied to detect carbaryl in green tea samples without pretreatment. The study afforded an efficient and desirable fluorescence sensor for carbaryl detection in a complicated matrix, which hopefully will be used for biomedical/chemical sensing recognition. Graphical abstract.


Assuntos
Gadolínio/química , Nanopartículas Metálicas/química , Dióxido de Silício/química , Chá/química , Fluorescência
14.
Stem Cell Res Ther ; 10(1): 118, 2019 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-30987681

RESUMO

BACKGROUND: Adult stem cells exist in a quiescent state (G0) within the in vivo niche; the loss of quiescence often leads to a decrease in the number and function of adult stem cells, impairing tissue regeneration and repair. Endogenous repair by nucleus pulposus-derived stem cells has recently shown promising regenerative potential for the treatment of intervertebral disc degeneration (IDD). However, the number and function of nucleus pulposus stem cells (NPSCs) declined throughout the process of IDD. This effect may have a specific relationship with quiescence. However, the biology of the quiescent NPSCs has not been reported. METHODS: First, we established an in vitro model for NPSC quiescence with serum starvation. The induction of G0 was confirmed by flow cytometry analyses of dual staining with Hoechst 33342 and Pyronin Y, immunofluorescent staining with Ki67 and Western blot analysis of P27 expression. NPSCs were cultured under serum starvation conditions for a long time period (21 days). To examine the functional phenotype of quiescent NPSCs, the cells were reactivated with 10% serum and differentiated into osteogenic and chondrogenic lineages in vitro. The number of colony-forming units was also estimated. To elucidate the role of autophagy in the quiescence of NPSCs, we activated and inhibited autophagy in starved cells with rapamycin and chloroquine, respectively. Then, the expression of P27 was evaluated by Western blot analysis, and the immunofluorescence of Ki67 was assessed. Finally, we assessed the role of P27 siRNA in NPSC quiescence by flow cytometry analyses and 5-ethynyl-20-deoxyuridine incorporation assays under normal and serum-starved conditions. RESULTS: NPSC quiescence was induced by 48 h of serum starvation, and they maintained quiescence for up to 21 days. Upon reactivation with serum, the quiescent NPSCs re-entered the cell cycle and exhibited enhanced clonogenic self-renewal, osteogenic differentiation and chondrogenic differentiation potentials compared to control NPSCs under normal culture conditions. We also found that autophagy underlay serum starvation-induced NPSC quiescence. Further study demonstrated that autophagy mediated the quiescence of NPSCs by regulating P27. CONCLUSIONS: Serum starvation efficiently induces quiescence in NPSCs. Quiescent NPSCs maintain stem cell properties. Our study reveals that autophagy plays a role in maintaining NPSC quiescence and that autophagy mediates the quiescence of NPSCs by regulating P27. We conclude that the induction of quiescence in cultured NPSCs provides a useful model for the analysis of mechanisms that might be relevant to the biology of NPSCs in vivo.

15.
J Comput Biol ; 26(8): 836-845, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30990327

RESUMO

Protein phosphorylation is a kind of important post-translational modification of protein, which plays a critical role in many biological processes of eukaryote. Identifying kinase-substrate interactions is helpful to understand the mechanism of many diseases. Many computational algorithms for kinase-substrate interactions identification have been proposed. However, most of those methods are mainly focused on utilizing protein local sequence information. In this article, we propose a new computational method to predict kinase-substrate interactions based on protein-protein interaction (PPI) network. Different from existing methods, the PPI network is utilized to measure the similarities of kinase-kinase and substrate-substrate, respectively. Then, the pairwise similarities of kinase-kinase and substrate-substrate are adjusted based on the assumption that the similarities of kinase-kinase and substrate-substrate are more reliable if they are in the same cluster. Finally, the bi-random walk is used to predict potential kinase-substrate interactions. The experimental results show that our method outperforms other state-of-the-art algorithms in performance. Furthermore, the case study demonstrates that it is effective in predicting potential kinase-substrate interactions.

16.
Sci Total Environ ; 654: 1270-1283, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30841400

RESUMO

Methane emission from ruminants not only causes serious environmental problems, but also represents a significant source of energy loss to animals. The increasing demand for sustainable animal production is driving researchers to explore proper strategies to mitigate ruminal methanogenesis. Since hydrogen is the primary substrate of ruminal methanogenesis, hydrogen metabolism and its associated microbiome in the rumen may closely relate to low- and high-methane phenotypes. Using candidate microbes that can compete with methanogens and redirect hydrogen away from methanogenesis as ruminal methane mitigants are promising avenues for methane mitigation, which can both prevent the adverse effects deriving from chemical additives such as toxicity and resistance, and increase the retention of feed energy. This review describes the ruminal microbial ecosystem and its association with methane production, as well as the effects of interspecies hydrogen transfer on methanogenesis. It provides a scientific perspective on using bacteria that are involved in hydrogen utilization as ruminal modifiers to decrease methanogenesis. This information will be helpful in better understanding the key role of ruminal microbiomes and their relationship with methane production and, therefore, will form the basis of valuable and eco-friendly methane mitigation methods while improving animal productivity.


Assuntos
Metano/metabolismo , Microbiota , Ruminantes/microbiologia , Animais , Bactérias/metabolismo , Fermentação , Hidrogênio/metabolismo , Rúmen/microbiologia
17.
J Anal Methods Chem ; 2019: 4372395, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30719372

RESUMO

In this paper, mid- and near-infrared spectroscopy fingerprints were combined to simultaneously discriminate 12 famous green teas and quantitatively characterize their antioxidant activities using chemometrics. A supervised pattern recognition method based on partial least square discriminant analysis (PLSDA) was adopted to classify the 12 famous green teas with different species and quality grades, and then optimized sample-weighted least-squares support vector machine (OSWLS-SVM) based on particle swarm optimization was employed to investigate the quantitative relationship between their antioxidant activities and the spectral fingerprints. As a result, 12 famous green teas can be discriminated with a recognition rate of 100% by MIR or NIR data. However, compared with individual instrumental data, data fusion was more adequate for modeling the antioxidant activities of samples with RMSEP of 0.0065. Finally, the performance of the proposed method was evaluated and validated by some statistical parameters and the elliptical joint confidence region (EJCR) test. The results indicate that fusion of mid- and near-infrared spectroscopy suggests a new avenue to discriminate the species and grades of green teas. Moreover, the proposed method also implies other promising applications with more accurate multivariate calibration of antioxidant activities.

18.
Int J Mol Sci ; 20(2)2019 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-30646505

RESUMO

Protein phosphorylation is an important chemical modification catalyzed by kinases. It plays important roles in many cellular processes. Predicting kinase⁻substrate interactions is vital to understanding the mechanism of many diseases. Many computational methods have been proposed to identify kinase⁻substrate interactions. However, the prediction accuracy still needs to be improved. Therefore, it is necessary to develop an efficient computational method to predict kinase⁻substrate interactions. In this paper, we propose a novel computational approach, KSIMC, to identify kinase⁻substrate interactions based on matrix completion. Firstly, the kinase similarity and substrate similarity are calculated by aligning sequence of kinase⁻kinase and substrate⁻substrate, respectively. Then, the original association network is adjusted based on the similarities. Finally, the matrix completion is used to predict potential kinase⁻substrate interactions. The experiment results show that our method outperforms other state-of-the-art algorithms in performance. Furthermore, the relevant databases and scientific literature verify the effectiveness of our algorithm for new kinase⁻substrate interaction identification.


Assuntos
Biologia Computacional , Fosfotransferases/química , Mapeamento de Interação de Proteínas , Algoritmos , Fenômenos Biofísicos , Bases de Dados Factuais , Humanos , Modelos Teóricos , Fosforilação , Fosfotransferases/antagonistas & inibidores , Alinhamento de Sequência , Especificidade por Substrato
19.
ACS Appl Mater Interfaces ; 11(9): 8992-9001, 2019 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-30694040

RESUMO

Developing high-performance, flexible, transparent supercapacitors for wearable electronics represents an important challenge, as it requires active materials to be sufficiently transparent without compromising energy storage. Here, we manipulate the morphology of the active materials and the junctions on the current collector to achieve optimum electronic/ionic transport kinetics. Two-dimensional Co(OH)2 nanosheets with single or two layers were vertically aligned onto a modified Ag nanowires (AgNWs) network using an electrochemical deposition-UV irradiation approach. The metallic AgNWs network endows high transparency while minimizing the contact resistance with the pseudocapacitive Co(OH)2 nanosheets. The Co(OH)2 nanosheets self-assembled into a three-dimensional array, which is beneficial for the fast ion movements. The rational materials design greatly boosts the electrochemical performance of the hybrid network, including an ultrahigh areal capacitance up to 3108 µC cm-2 (5180 µF cm-2) coupled with long cycle life (20 000 cycles). As a prototype device, the symmetric supercapacitor well combines high energy/power density and excellent mechanical flexibility and long-term performance, suggesting a promising application for the next-generation wearable electronics.

20.
Artigo em Inglês | MEDLINE | ID: mdl-29990253

RESUMO

MicroRNAs (miRNAs) are a class of non-coding RNAs about  âˆ¼ 22nt nucleotides. Studies have proven that miRNAs play key roles in many human complex diseases. Therefore, discovering miRNA-disease associations is beneficial to understanding disease mechanisms, developing drugs, and treating complex diseases. It is well known that it is a time-consuming and expensive process to discover the miRNA-disease associations via biological experiments. Alternatively, computational models could provide a low-cost and high-efficiency way for predicting miRNA-disease associations. In this study, we propose a method (called DNRLMF-MDA) to predict miRNA-disease associations based on dynamic neighborhood regularized logistic matrix factorization. DNRLMF-MDA integrates known miRNA-disease associations, functional similarity and Gaussian Interaction Profile (GIP) kernel similarity of miRNAs, and functional similarity and GIP kernel similarity of diseases. Especially, positive observations (known miRNA-disease associations) are assigned higher importance levels than negative observations (unknown miRNA-disease associations).DNRLMF-MDA computes the probability that a miRNA would interact with a disease by a logistic matrix factorization method, where latent vectors of miRNAs and diseases represent the properties of miRNAs and diseases, respectively, and further improve prediction performance via dynamic neighborhood regularized. The 5-fold cross validation is adopted to assess the performance of our DNRLMF-MDA, as well as other competing methods for comparison. The computational experiments show that DNRLMF-MDA outperforms the state-of-art method PBMDA. The AUC values of DNRLMF-MDA on three datasets are 0.9357, 0.9411, and 0.9416, respectively, which are superior to the PBMDA's results of 0.9218, 0.9187, and 0.9262. The average computation times per 5-fold cross validation of DNRLMF-MDA on three datasets are 38, 46, and 50 seconds, which are shorter than the PBMDA's average computation times of 10869, 916, and 8448 seconds, respectively. DNRLMF-MDA also can predict potential diseases for new miRNAs. Furthermore, case studies illustrate that DNRLMF-MDA is an effective method to predict miRNA-disease associations.


Assuntos
Biologia Computacional/métodos , MicroRNAs/genética , Modelos Genéticos , Neoplasias/genética , Algoritmos , Área Sob a Curva , Bases de Dados Genéticas , Humanos , MicroRNAs/metabolismo , Neoplasias/metabolismo
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