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Most of the ONOO- fluorescent probes have restricted applications because of their aggregation-caused quenching (ACQ) effect, long response time and low fluorescence enhancement. Herein, we developed a novel AIEgen fluorescent probe (PE-XY) based on a benzothiazole and quinolin scaffold with high sensitivity and selectivity for imaging of ONOO-. The results indicated that probe PE-XY exhibited fast response towards ONOO- with 2000-fold enhancement of fluorescence intensity ratio in vitro. Moreover, PE-XY exhibited a relatively high sensitivity (limit of detection: 8.58 nM), rapid response (<50 s), high fluorescence quantum yield (δ = 0.81) and excellent selectivity over other analytes towards ONOO-in vitro. Furthermore, PE-XY was successfully applied to detect endogenous ONOO- levels in living HeLa cells, C. elegans and inflammatory mice with low cytotoxicity. Overall, this work provided a novel fast-response and highly selective AIEgen fluorescent probe for real-time monitoring ONOO- fluctuations in living systems.
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Colorantes Fluorescentes , Ácido Peroxinitroso , Animales , Caenorhabditis elegans , Fluorescencia , Colorantes Fluorescentes/toxicidad , Células HeLa , Humanos , Ratones , Ácido Peroxinitroso/toxicidadRESUMEN
We developed a label-free, real-time, and highly sensitive nucleic acid biosensor based on fiber optic particle plasmon resonance (FOPPR). The biosensor employs a single-strand deoxyoligonucleotides (ssDNA) probe, conjugated to immobilized gold nanoparticles on the core surface of an optical fiber. We explore the steric effects on hybridization affinity and limit of detection (LOD), by using different ssDNA probe designs and surface chemistries, including diluent molecules of different lengths in mixed self-assembled monolayers, ssDNA probes of different oligonucleotide lengths, ssDNA probes in different orientations to accommodate target oligonucleotides with a hybridization region located unevenly in the strand. Based on the optimized ssDNA probe design and surface chemistry, we achieved LOD at sub-nM level, which makes detection of target oligonucleotides as low as 1 fmol possible in the 10-mL sensor chip. Additionally, the FOPPR biosensor shows a good correlation in determining HLA-B27 mRNA, in extracted blood samples from patients with ankylosing spondylitis (AS), with the clinically accepted real-time reverse transcription-polymerase chain reaction (RT-PCR) method. The results from this fundamental study should guide the design of ssDNA probe for anti-sense sensing. Further results through application to HLA-B27 mRNA detection illustrate the feasibility in detecting various nucleic acids of chemical and biological relevance.
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Técnicas Biosensibles , Nanopartículas del Metal , ARN Mensajero/análisis , Espondilitis Anquilosante , Sondas de ADN , ADN de Cadena Simple , Oro , Antígeno HLA-B27/genética , Humanos , Hibridación de Ácido Nucleico , Espondilitis Anquilosante/diagnóstico , Espondilitis Anquilosante/genética , Resonancia por Plasmón de SuperficieRESUMEN
MOTIVATION: Several efficient gene-gene interaction tests have been developed for unrelated case-control samples in genome-wide association studies (GWAS), making it possible to test tens of billions of interaction pairs of single-nucleotide polymorphisms (SNPs) in a reasonable timeframe. However, current family-based gene-gene interaction tests are computationally expensive and are not applicable to genome-wide interaction analysis. RESULTS: We developed an efficient family-based gene-gene interaction test, GCORE, for trios (i.e. two parents and one affected sib). The GCORE compares interlocus correlations at two SNPs between the transmitted and non-transmitted alleles. We used simulation studies to compare the statistical properties such as type I error rates and power for the GCORE with several other family-based interaction tests under various scenarios. We applied the GCORE to a family-based GWAS for autism consisting of approximately 2000 trios. Testing a total of 22 471 383 013 interaction pairs in the GWAS can be finished in 36 h by the GCORE without large-scale computing resources, demonstrating that the test is practical for genome-wide gene-gene interaction analysis in trios. AVAILABILITY AND IMPLEMENTATION: GCORE is implemented with C ++ and is available at http://gscore.sourceforge.net CONTACT: rchung@nhri.org.tw SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.
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Estudio de Asociación del Genoma Completo , Interpretación Estadística de Datos , Epistasis Genética , Humanos , Padres , Polimorfismo de Nucleótido SimpleRESUMEN
BACKGROUND: Genome-wide association studies (GWAS) have become a common approach to identifying single nucleotide polymorphisms (SNPs) associated with complex diseases. As complex diseases are caused by the joint effects of multiple genes, while the effect of individual gene or SNP is modest, a method considering the joint effects of multiple SNPs can be more powerful than testing individual SNPs. The multi-SNP analysis aims to test association based on a SNP set, usually defined based on biological knowledge such as gene or pathway, which may contain only a portion of SNPs with effects on the disease. Therefore, a challenge for the multi-SNP analysis is how to effectively select a subset of SNPs with promising association signals from the SNP set. RESULTS: We developed the Optimal P-value Threshold Pedigree Disequilibrium Test (OPTPDT). The OPTPDT uses general nuclear families. A variable p-value threshold algorithm is used to determine an optimal p-value threshold for selecting a subset of SNPs. A permutation procedure is used to assess the significance of the test. We used simulations to verify that the OPTPDT has correct type I error rates. Our power studies showed that the OPTPDT can be more powerful than the set-based test in PLINK, the multi-SNP FBAT test, and the p-value based test GATES. We applied the OPTPDT to a family-based autism GWAS dataset for gene-based association analysis and identified MACROD2-AS1 with genome-wide significance (p-value=2.5×10(-6)). CONCLUSIONS: Our simulation results suggested that the OPTPDT is a valid and powerful test. The OPTPDT will be helpful for gene-based or pathway association analysis. The method is ideal for the secondary analysis of existing GWAS datasets, which may identify a set of SNPs with joint effects on the disease.
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Algoritmos , Biología Computacional/métodos , Enfermedad/genética , Estudio de Asociación del Genoma Completo , Linaje , Polimorfismo de Nucleótido Simple , Trastorno Autístico/genética , Femenino , Genómica , Humanos , Masculino , Núcleo FamiliarRESUMEN
The aim of the paper is to use data mining technology to establish a classification of breast cancer survival patterns, and offers a treatment decision-making reference for the survival ability of women diagnosed with breast cancer in Taiwan. We studied patients with breast cancer in a specific hospital in Central Taiwan to obtain 1,340 data sets. We employed a support vector machine, logistic regression, and a C5.0 decision tree to construct a classification model of breast cancer patients' survival rates, and used a 10-fold cross-validation approach to identify the model. The results show that the establishment of classification tools for the classification of the models yielded an average accuracy rate of more than 90% for both; the SVM provided the best method for constructing the three categories of the classification system for the survival mode. The results of the experiment show that the three methods used to create the classification system, established a high accuracy rate, predicted a more accurate survival ability of women diagnosed with breast cancer, and could be used as a reference when creating a medical decision-making frame.
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Neoplasias de la Mama/mortalidad , Simulación por Computador , Árboles de Decisión , Máquina de Vectores de Soporte , Análisis de Supervivencia , Neoplasias de la Mama/patología , Minería de Datos , Bases de Datos Factuales , Femenino , Humanos , Modelos Logísticos , Estadificación de Neoplasias , Tasa de Supervivencia , TaiwánRESUMEN
Systemic lupus erythematosus (SLE) can present with movement disorders, among which chorea is closely associated with antiphospholipid (aPL) antibodies. Brain imaging results obtained in patients with chorea are generally inconsistent with the clinical manifestation of chorea; moreover, medical tests for hemichorea, which are expected to reveal distinct localization, may show negative findings. Herein, we present a case of a 15-year-old girl with SLE who had a history of left cerebral infarction; tests revealed elevated aPL levels, and she developed recurrent left hemichorea 2 years later. Brain magnetic resonance imaging (MRI) results revealed no acute lesions during each episode of involuntary movements, and an MRI perfusion scan failed to provide an explanation for the asymmetric presentation. Although various hypotheses have been proposed regarding the mechanism underlying the occurrence of chorea, some scenarios still remain unexplained. Further investigation on the pathophysiology of chorea in SLE may be warranted to clarify its prognosis.
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Corea , Lupus Eritematoso Sistémico , Femenino , Humanos , Adolescente , Corea/diagnóstico , Corea/tratamiento farmacológico , Corea/etiología , Lupus Eritematoso Sistémico/complicaciones , Lupus Eritematoso Sistémico/diagnóstico , Lupus Eritematoso Sistémico/tratamiento farmacológico , Infarto Cerebral/etiología , Infarto Cerebral/complicaciones , Anticuerpos Antifosfolípidos , EncéfaloRESUMEN
Novel therapeutics for the treatment of ischemic stroke remains to be the unmet clinical needs. Previous studies have indicated that salvianolic acid A (SAA) is a promising candidate for the treatment of the brain diseases. However, SAA has poor absolute bioavailability and does not efficiently cross the intact blood-brain barrier (BBB), which limit its efficacy. To this end we developed a brain-targeted liposomes for transporting SAA via the BBB by incorporating the liposomes to a transport receptor, insulin-like growth factor-1 receptor (IGF1R). The liposomes were prepared by ammonium sulfate gradients loading method. The prepared SAA-loaded liposomes (Lipo/SAA) were modified with IGF1R monoclonal antibody to generate IGF1R antibody-conjugated Lipo/SAA (IGF1R-targeted Lipo/SAA). The penetration of IGF1R-targeted Lipo/SAA into the brain was confirmed by labeling with Texas Red, and their efficacy were evaluate using middle cerebral artery occlusion (MCAO) model. The results showed that IGF1R-targeted Lipo/SAA are capable of transporting SAA across the BBB into the brain, accumulation in brain tissue, and sustained releasing SAA for several hours. Administration o IGF1R-targeted Lipo/SAA notably reduced infarct size and neuronal damage, improved neurological function and inhibited cerebral inflammation, which had much higher efficiency than no-targeted SAA.
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Accidente Cerebrovascular Isquémico , Liposomas , Animales , Accidente Cerebrovascular Isquémico/tratamiento farmacológico , Masculino , Ácidos Cafeicos/administración & dosificación , Ácidos Cafeicos/química , Ácidos Cafeicos/farmacología , Barrera Hematoencefálica/efectos de los fármacos , Barrera Hematoencefálica/metabolismo , Receptor IGF Tipo 1/metabolismo , Ratones , Lactatos/administración & dosificación , Lactatos/química , Infarto de la Arteria Cerebral Media/tratamiento farmacológico , Sistemas de Liberación de Medicamentos/métodos , Ratas Sprague-Dawley , Ratas , Encéfalo/metabolismo , Encéfalo/efectos de los fármacosRESUMEN
Chaos-based image cipher has been widely investigated over the last decade or so to meet the increasing demand for real-time secure image transmission over public networks. In this paper, an improved diffusion strategy is proposed to promote the efficiency of the most widely investigated permutation-diffusion type image cipher. By using the novel bidirectional diffusion strategy, the spreading process is significantly accelerated and hence the same level of security can be achieved with fewer overall encryption rounds. Moreover, to further enhance the security of the cryptosystem, a plain-text related chaotic orbit turbulence mechanism is introduced in diffusion procedure by perturbing the control parameter of the employed chaotic system according to the cipher-pixel. Extensive cryptanalysis has been performed on the proposed scheme using differential analysis, key space analysis, various statistical analyses and key sensitivity analysis. Results of our analyses indicate that the new scheme has a satisfactory security level with a low computational complexity, which renders it a good candidate for real-time secure image transmission applications.
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Algoritmos , Redes de Comunicación de Computadores , Seguridad Computacional , Compresión de Datos/métodos , Interpretación de Imagen Asistida por Computador/métodos , Procesamiento de Señales Asistido por Computador , Difusión , Dinámicas no LinealesRESUMEN
Background: The commonly used screening tests for Parkinson's disease (PD) are the Montreal Cognitive Assessment (MoCA) and Mini-Mental State Examination (MMSE), both of which only focus on cognitive function. A composite assessment that considers both cognitive and social dysfunction in PD would be helpful in detecting mild cognitive impairment (MCI) and PD dementia (PDD). Objective: We aimed to simplify the commonly used tools and combine cognitive and social functioning tests to detect early MCI and PDD. Materials and Methods: A total of 166 participants (84 PD patients and 82 healthy) were recruited who completed the MMSE, MoCA, PD social functioning scale (PDSFS), clock drawing test, activities of daily living, comprehensive neuropsychological assessment (e.g., executive, attention, language, memory, and visuospatial functions), and movement disorder society (MDS)-unified PD rating scale. According to the MDS diagnostic criteria, the patients were grouped into PD-nonMCI, PD-MCI, or PDD. Results: To detect PD-MCI, the optimal cut-off scores for the simplified MoCA and the combined test were 9 and 35. The discrimination values measured by the area under the receiver operating characteristic curve (AUC) of the two tests were 0.767 (p < 0.001) and 0.790 (p < 0.001). When the simplified MoCA was 7 or the combined test 30, the patients would be classified as having PDD. The AUCs of the two tests were 0.846 (p < 0.001) and 0.794 (p = 0.003). Conclusion: We suggest considering both cognitive and social functions when detecting PD-MCI and PDD.
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Theranostic prodrug was highly desirable for precise diagnosis and anti-cancer therapy to decrease side effects. However, it is difficult to conjugate chemo-drug and molecular probe for combined therapy due to the complex pharmacokinetics of different molecules. Here, a novel anticancer theranostic prodrug (BTMP-SS-PTX) had been designed and synthesized by conjugating paclitaxel (PTX) with 2-(benzo[d]thiazol-2-yl)-4-methoxyphenol (BTMP) through a disulphide (-S-S-) linkage, which was redox-sensitive to the high concentration of glutathione in tumors. Upon activation with glutathione in weakly acid media, the BTMP-SS-PTX can be dissociated to release free PTX and visible BTMP, which realized the visual tracking of free drug. The cytotoxicity study demonstrated that soluble prodrug BTMP-SS-PTX displayed more outstanding anticancer activity in HepG2, MCF-7 and HeLa cells, lower toxicity to non-cancer cells (293 T) than free drugs. Furthermore, BTMP-SS-PTX was still able to induce apoptosis of HeLa cells and significantly inhibited tumor growth in HeLa-xenograft mouse model. On the basis of these findings, BTMP-SS-PTX could play a potential role in cancer diagnosis and therapy.
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Antineoplásicos/farmacología , Glutatión/farmacología , Profármacos/farmacología , Animales , Antineoplásicos/síntesis química , Antineoplásicos/química , Apoptosis/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Células Cultivadas , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Femenino , Glutatión/química , Células HEK293 , Humanos , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Estructura Molecular , Neoplasias Experimentales/diagnóstico por imagen , Neoplasias Experimentales/tratamiento farmacológico , Imagen Óptica , Profármacos/síntesis química , Profármacos/química , Solubilidad , Relación Estructura-Actividad , Distribución TisularRESUMEN
Bone metastasis of malignant solid tumors has become one of the most serious complications, especially in breast cancer, which was particularly challenging for early detection and treatment in clinical practice. In this work, we reported a new fluorescently labeled bisphosphonate for bone metastasis detection of breast cancer. The designed probes were based on Rhodamine B and bisphosphonate as recognition group, which can specifically target hydroxyapatite (HA) existed in bone tissue. After the osteoclasts were adsorbed on the bone surface, the surrounding microenvironment was acidified, causing the HA to locally dissolve. The probe bound to the HA was then released, and realized the fluorescence turn on under acidic conditions. In vitro experiments showed that G0 was more excellent than G2 owing to shorter connecting arm. Subsequently, we proved that G0 could combine with HA rapidly and exhibit excellent response in solid state. More importantly, we established a model of bone metastasis with MDA-MB-231 cells which was similar to the clinical cases and evaluated the theranostics value of G0 prospectively, which provide the potential application prospect in clinical.
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Neoplasias Óseas , Neoplasias de la Mama , Neoplasias Óseas/tratamiento farmacológico , Huesos , Neoplasias de la Mama/tratamiento farmacológico , Difosfonatos , Femenino , Humanos , Osteoclastos , Medicina de Precisión , Microambiente TumoralRESUMEN
Zika virus (ZIKV) is transmitted by Aedes mosquitoes and exhibits genetic variation with African and Asian lineages. ZIKV Natal RGN strain, an Asian-lineage virus, has been identified in brain tissues from fetal autopsy cases with microcephaly and is suggested to be a neurotropic variant. However, ZIKV Natal RGN strain has not been isolated; its biological features are not yet illustrated. This study rescued and characterized recombinant, single-round infectious particles (SRIPs) of the ZIKV Natal RGN strain using reverse genetic and synthetic biology techniques. The DNA-launched replicon of ZIKV Natal RGN was constructed and contains the EGFP reporter, lacks prM-E genes, and replicates under CMV promoter control. The peak in the ZIKV Natal RGN SRIP titer reached 6.25 × 106 TCID50/mL in the supernatant of prM-E-expressing packaging cells 72 h post-transfection with a ZIKV Natal RGN replicon. The infectivity of ZIKV Natal RGN SRIPs has been demonstrated to correlate with the green florescence intensity of the EGFP reporter, the SRIP-induced cytopathic effect, and ZIKV's non-structural protein expression. Moreover, ZIKV Natal RGN SRIPs effectively self-replicated in rhabdomyosarcoma/muscle, glioblastoma/astrocytoma, and retinal pigmented epithelial cells, displaying unique cell susceptibility with differential attachment activity. Therefore, the recombinant ZIKV Natal RGN strain was rescued as SRIPs that could be used to elucidate the biological features of a neurotropic strain regarding cell tropism and pathogenic components, apply for antiviral agent screening, and develop vaccine candidates.
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Replicación Viral , Virus Zika/genética , Línea Celular , ADN Recombinante , Genes Reporteros/genética , Humanos , Microcefalia/virología , Replicón/genética , Genética Inversa , Biología Sintética , Carga Viral , Proteínas no Estructurales Virales/metabolismo , Ensamble de Virus , Virus Zika/patogenicidad , Infección por el Virus Zika/virologíaRESUMEN
Pathway analysis has become popular as a secondary analysis strategy for genome-wide association studies (GWAS). Most of the current pathway analysis methods aggregate signals from the main effects of single nucleotide polymorphisms (SNPs) in genes within a pathway without considering the effects of gene-gene interactions. However, gene-gene interactions can also have critical effects on complex diseases. Protein-protein interaction (PPI) networks have been used to define gene pairs for the gene-gene interaction tests. Incorporating the PPI information to define gene pairs for interaction tests within pathways can increase the power for pathway-based association tests. We propose a pathway association test, which aggregates the interaction signals in PPI networks within a pathway, for GWAS with case-control samples. Gene size is properly considered in the test so that genes do not contribute more to the test statistic simply due to their size. Simulation studies were performed to verify that the method is a valid test and can have more power than other pathway association tests in the presence of gene-gene interactions within a pathway under different scenarios. We applied the test to the Wellcome Trust Case Control Consortium GWAS datasets for seven common diseases. The most significant pathway is the chaperones modulate interferon signaling pathway for Crohn's disease (p-value = 0.0003). The pathway modulates interferon gamma, which induces the JAK/STAT pathway that is involved in Crohn's disease. Several other pathways that have functional implications for the seven diseases were also identified. The proposed test based on gene-gene interaction signals in PPI networks can be used as a complementary tool to the current existing pathway analysis methods focusing on main effects of genes. An efficient software implementing the method is freely available at http://puppi.sourceforge.net.
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Enfermedad/genética , Epistasis Genética , Mapas de Interacción de Proteínas/genética , Algoritmos , Simulación por Computador , Enfermedad de Crohn/genética , Enfermedad de Crohn/metabolismo , Bases de Datos Genéticas , Estudio de Asociación del Genoma Completo , Humanos , Modelos Genéticos , Polimorfismo de Nucleótido Simple , Transducción de Señal/genética , Programas InformáticosRESUMEN
OBJECTIVES: Growth arrest-specific 6 (Gas6), a vitamin K-dependent protein, has been implicated in systemic inflammation, obesity, and insulin resistance (IR). Data from recent studies suggest that polymorphisms in the Gas6 gene are associated with cardiovascular disorders and type 2 diabetes (T2D). However, the association of Gas6 gene variants with obesity, IR, and T2D development has not been explored. MATERIALS AND METHODS: Four common single nucleotide polymorphisms (SNPs) in the Gas6 gene were genotyped in 984 participants from the Stanford Asia-Pacific Program for Hypertension and Insulin Resistance (SAPPHIRe) family cohort. An insulin suppression test was performed to determine IR based on steady-state plasma glucose (SSPG). Associations between IR indices and obesity, and SNP genotypes, based on previously-reported data for this cohort (Phase I), were analyzed. In the present follow-up study (Phase II), the effects of gene variants of Gas6 on the progression to T2D were explored in individuals who were free of T2D in Phase I. The mean follow-up period for Phase II was 5.7 years. RESULTS: The mean age of the study population in Phase I was 49.5 years and 16.7% of individuals developed T2D during follow-up. After adjusting for covariates, three SNPs (rs8191973, rs8197974, and rs7323932) were found to be associated with SSPG levels (p = 0.007, p = 0.03, and p = 0.011, respectively). This association remained significant after multiple testing and showed a significant interaction with physical activity for SNP rs8191973. However, no other significant correlations were observed between Gas6 polymorphisms and other indices of IR or obesity. A specific haplotype, AACG (from rs8191974, rs7323932, rs7331124, and rs8191973), was positively associated with SSPG levels (p = 0.0098). None of the polymorphisms were associated with an increased risk of T2D development. CONCLUSIONS: Our results suggest that Gas6 gene variants are associated with IR, although their effects on subsequent progression to T2D were minimal in this prospective Asian cohort.
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Pueblo Asiatico/genética , Diabetes Mellitus Tipo 2/genética , Resistencia a la Insulina/genética , Péptidos y Proteínas de Señalización Intercelular/genética , Obesidad/genética , Polimorfismo de Nucleótido Simple , Femenino , Frecuencia de los Genes , Predisposición Genética a la Enfermedad/genética , Humanos , Desequilibrio de Ligamiento , Masculino , Persona de Mediana EdadRESUMEN
Most studies treat fine motor as one subscale in a developmental test, hence, further factor analysis of fine motor has not been conducted. In fact, fine motor has been treated as a multi-dimensional domain from both clinical and theoretical perspectives, and therefore to know its factors would be valuable. The aim of this study is to analyze the internal consistency and factor validity of the Contextual Fine Motor Questionnaire (CFMQ). Based on the ecological observation and literature, the Contextual Fine Motor Questionnaire (CFMQ) was developed and includes 5 subscales: Pen Control, Tool Use During Handicraft Activities, the Use of Dining Utensils, Connecting and Separating during Dressing and Undressing, and Opening Containers. The main purpose of this study is to establish the factorial validity of the CFMQ through conducting this factor analysis study. Among 1208 questionnaires, 904 were successfully completed. Data from the children's CFMQ submitted by primary care providers was analyzed, including 485 females (53.6%) and 419 males (46.4%) from grades 1 to 5, ranging in age from 82 to 167 months (M=113.9, SD=16.3). Cronbach's alpha was used to measure internal consistency and explorative factor analysis was applied to test the five factor structures within the CFMQ. Results showed that Cronbach's alpha coefficient of the CFMQ for 5 subscales ranged from .77 to .92 and all item-total correlations with corresponding subscales were larger than .4 except one item. The factor loading of almost all items classified to their factor was larger than .5 except 3 items. There were five factors, explaining a total of 62.59% variance for the CFMQ. In conclusion, the remaining 24 items in the 5 subscales of the CFMQ had appropriate internal consistency, test-retest reliability and construct validity.
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Actividades Cotidianas , Desarrollo Infantil , Destreza Motora , Adolescente , Niño , Análisis Factorial , Femenino , Humanos , Masculino , Psicometría/instrumentación , Reproducibilidad de los Resultados , Encuestas y CuestionariosRESUMEN
A computer-aided diagnostic system for colonoscopic imaging has been developed to classify colorectal polyps by type. The modules of the proposed system include image enhancement, feature extraction, feature selection and polyp classification. Three hundred sixty-five images (214 with hyperplastic polyps and 151 with adenomatous polyps) were collected from a branch of a medical center in central Taiwan. The raw images were enhanced by the principal component transform (PCT). The features of texture analysis, spatial domain and spectral domain were extracted from the first component of the PCT. Sequential forward selection (SFS) and sequential floating forward selection (SFFS) were used to select the input feature vectors for classification. Support vector machines (SVMs) were employed to classify the colorectal polyps by type. The classification performance was measured by the Az values of the Receiver Operating Characteristic curve. For all 180 features used as input vectors, the test data set yielded Az values of 88.7%. The Az value was increased by 2.6% (from 88.7% to 91.3%) and 4.4% (from 88.7% to 93.1%) for the features selected by the SFS and the SFFS, respectively. The SFS and the SFFS reduced the dimension of the input vector by 57.2% and 73.8%, respectively. The SFFS outperformed the SFS in both the reduction of the dimension of the feature vector and the classification performance. When the colonoscopic images were visually inspected by experienced physicians, the accuracy of detecting polyps by types was around 85%. The accuracy of the SFFS with the SVM classifier reached 96%. The classification performance of the proposed system outperformed the conventional visual inspection approach. Therefore, the proposed computer-aided system could be used to improve the quality of colorectal polyp diagnosis.
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Algoritmos , Inteligencia Artificial , Pólipos del Colon/patología , Colonoscopía/métodos , Interpretación de Imagen Asistida por Computador/métodos , Reconocimiento de Normas Patrones Automatizadas/métodos , Enfermedades del Recto/patología , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Aumento de la Imagen/métodos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Sensibilidad y EspecificidadRESUMEN
Crystalline Gaq(3) 1-D nanostructures and nanospheres could be fabricated by thermal evaporation under cold trap. The influences of the key process parameters on formation of the nanostructures were also investigated. It has been demonstrated that the morphology and dimension of the nanostructures were mainly controlled by working temperature and working pressure. One-dimensional nanostructures were fabricated at a lower working temperature, whereas nanospheres were formed at a higher working temperature. Larger nanospheres could be obtained when a higher working pressure was applied. The XRD, FTIR, and NMR analyses evidenced that the nanostructures mainly consisted of delta-phase Gaq(3). Their DSC trace revealed two small exothermic peaks in addition to the melting endotherm. The one in lower temperature region was ascribed to a transition from delta to beta phase, while another in higher temperature region could be identified as a transition from beta to delta phase. All the crystalline nanostructures show similar PL spectra due to absence of quantum confinement effect. They also exhibited a spectral blue shift because of a looser interligand spacing and reduced orbital overlap in their delta-phase molecular structures.
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Alumina nanotubes were fabricated by a template method. Tris-(8-hydroxyquinoline) gallium (GaQ3) organic nanowires were used as a soft template for coating with alumina using an atomic layer deposition technique. The deposition was conducted at 25 degrees C by using trimethylaluminum and distilled water as the precursors of Al2O3. Amorphous alumina nanotubes were obtained after removing the GaQ3 by dissolving in toluene or by heat treatment at 350 degrees C. The amorphous nanotubes could be crystallized by heating at 900 degrees C for 1 h in vacuum.