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... and Naidu, 1998) and the release of FeII and MnII under reducing conditions (Wada et al., 1983; Saejiew et al., 2004) are expected to be factors for clay flocculation. In this study, the SC and flocculation properties of the clay... more
... and Naidu, 1998) and the release of FeII and MnII under reducing conditions (Wada et al., 1983; Saejiew et al., 2004) are expected to be factors for clay flocculation. In this study, the SC and flocculation properties of the clay fraction of the puddled horizon from a typical paddy ...
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A data stream is an ordered sequence of instances that can be read only once or a small number of times using limited computing and storage capabilities. Stream data analysis is a critical issue in many application areas such as network... more
A data stream is an ordered sequence of instances that can be read only once or a small number of times using limited computing and storage capabilities. Stream data analysis is a critical issue in many application areas such as network fraud detection, stock market prediction, and web searches. In this research, our previously proposed FCMAC-BYY, that uses Bayesian Ying-Yang
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ABSTRACT Nowadays, audio podcasting has been widely used by many online sites such as newspapers, web portals, journals, and so forth, to deliver audio content to users through download or subscription. Within 1 to 30 minutes long of one... more
ABSTRACT Nowadays, audio podcasting has been widely used by many online sites such as newspapers, web portals, journals, and so forth, to deliver audio content to users through download or subscription. Within 1 to 30 minutes long of one podcast story, it is often that multiple audio advertisements (ads) are inserted into and repeated, with each of a length of 5 to 30 seconds, at different locations. Automatic detection of these attached ads is a challenging task due to the complexity of the search algorithms. Based on the knowledge of typical structures of podcast contents, this paper proposes a novel efficient advertisement discovery approach for large audio podcasting collections. The proposed approach offers a significant improvement on search speed with sufficient accuracy. The key to the acceleration comes from the advantages of candidate segmentation and sampling technique introduced to reduce both search areas and number of matching frames. The approach has been tested over a variety of podcast contents collected from MIT Technology Review, Scientific American, and Singapore Podcast websites. Experimental results show that the proposed algorithm archives detection rate of 97.5% with a significant computation saving as compared to existing state-of-the-art methods.
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This paper proposes an evolving fuzzy associative memory neural network model based on the fuzzy CMAC (FCMAC). FCMAC is an auto-associate memory feed forward neural network with attractive properties of fast learning and simple... more
This paper proposes an evolving fuzzy associative memory neural network model based on the fuzzy CMAC (FCMAC). FCMAC is an auto-associate memory feed forward neural network with attractive properties of fast learning and simple computation. Evolving techniques aim at building adaptive intelligent systems that evolve both their structure and parameters through incremental online learning. During fuzzification phase, the proposed ESOFCMAC
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SharedPlans is an agent teamwork model that provides a formaliza- tion of the conditions under which a group of agents has a collaborative plan. This paper describes a general framework for implementing SharedPlans theory that addresses... more
SharedPlans is an agent teamwork model that provides a formaliza- tion of the conditions under which a group of agents has a collaborative plan. This paper describes a general framework for implementing SharedPlans theory that addresses the computational issues of team formation, group plan elabora- tion and plan execution, involving coordination, communication and monitoring. The framework includes a team-oriented programming
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Enterohemorrhagic Escherichia coli O157:H7 was isolated for the first time in Vietnam. Shiga toxin- producing E. coli were isolated from 8 of 100 cows examined. The two strains showing serotype O157:H7 carried the eae, ehxA, and stx2c... more
Enterohemorrhagic Escherichia coli O157:H7 was isolated for the first time in Vietnam. Shiga toxin- producing E. coli were isolated from 8 of 100 cows examined. The two strains showing serotype O157:H7 carried the eae, ehxA, and stx2c genes, but the other six were negative for the eae gene. Escherichia coli is a common member of the normal flora of the
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Current methods of assessing psychopathology depend almost entirely on verbal report (clinical interview or questionnaire) of patients, their family, or caregivers. They lack systematic and efficient ways of incorporating behavioral... more
Current methods of assessing psychopathology depend almost entirely on verbal report (clinical interview or questionnaire) of patients, their family, or caregivers. They lack systematic and efficient ways of incorporating behavioral observations that are strong indicators of psychological disorder, much of which may occur outside the awareness of either individual. We compared clinical diagnosis of major depression with automatically measured facial
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The Microtubule (MT)-associated protein TPX2 is primarily defined as a factor required for mitotic spindle assembly and cell cycle progression. In interphase, which occupies a majority of the cell cycle time, TPX2 is actively imported in... more
The Microtubule (MT)-associated protein TPX2 is primarily defined as a factor required for mitotic spindle assembly and cell cycle progression. In interphase, which occupies a majority of the cell cycle time, TPX2 is actively imported in the nucleus, hypothetically to be segregated from Tubulin and prevent aberrant MT polymerization in the cytosol. We now report that TPX2 interacts directly with
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The theory of planned behavior and the stages-of-change model were used to gain a clearer understanding of the factors associated with regular exercise in order to plan more effective programs in heart disease prevention. The study was... more
The theory of planned behavior and the stages-of-change model were used to gain a clearer understanding of the factors associated with regular exercise in order to plan more effective programs in heart disease prevention. The study was conducted using a self-administered postal questionnaire sent to a sample of 2,269 men 30 to 60 years of age. Nearly a quarter (23.3%)
Research Interests: Health Promotion, Health Behavior, Community Health, Theory of Planned Behavior, Quebec, and 17 moreLogistic Regression, Humans, Male, Exercise, Heart Disease, Middle Aged, Self Assessment, Perceived Behavioral Control, Adult, Public health systems and services research, Health surveys, Cardiovascular Diseases, Volition, Psychological Models, Cross Sectional Studies, Logistic Models, and Socioeconomic Factors
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... ICARCV 2006 Stock Market Price Prediction using Cyclic Self-Organizing Hierarchical CMAC MN Nguyen, U. Omkar, D. Shi School of Computer Engineering Nanyang Technological University Singapore ... 2 ( / ) 1 1 ( ) ( ). v h i ji ji N N s... more
... ICARCV 2006 Stock Market Price Prediction using Cyclic Self-Organizing Hierarchical CMAC MN Nguyen, U. Omkar, D. Shi School of Computer Engineering Nanyang Technological University Singapore ... 2 ( / ) 1 1 ( ) ( ). v h i ji ji N N s j j j i ys asw e µ σ − − = = ...
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The discovery of cell cycle regulators has directed cell research into uncharted territory. In dividing cells, cell cycle-associated protein kinases, which are referred to as cyclin-dependent-kinases (Cdks), regulate proliferation,... more
The discovery of cell cycle regulators has directed cell research into uncharted territory. In dividing cells, cell cycle-associated protein kinases, which are referred to as cyclin-dependent-kinases (Cdks), regulate proliferation, differentiation, senescence and apoptosis. In contrast, all Cdks in post-mitotic neurons, with the notable exception of Cdk5, are silenced. Surprisingly, misregulation of Cdks occurs in neurons in a wide diversity of
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One of the important natural product investigations from marine algae is to focus on the pharmaceutically important compounds that can be applied in bone health. Osteoporosis is one of the bone diseases caused by an imbalance between bone... more
One of the important natural product investigations from marine algae is to focus on the pharmaceutically important compounds that can be applied in bone health. Osteoporosis is one of the bone diseases caused by an imbalance between bone formation and resorption. Promotion of osteoblast differentiation is one of the best therapeutic ways to combat osteoporosis. Osteoblasts are the cells responsible for bone formation by increasing the proliferation of the osteoblastic lineage or inducing differentiation of the osteoblasts. In this review, we describe the central effects of osteoblast differentiation by various bone therapy biomaterials from marine algae.
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This work reports on the synthesis of titanium bone implants functionalized with nanoparticles (NPs) containing Arg-Gly-Asp-Cys peptide (RGDC) and shows the adhesion behavior of cells seeded on these materials. RGDC peptides were first... more
This work reports on the synthesis of titanium bone implants functionalized with nanoparticles (NPs) containing Arg-Gly-Asp-Cys peptide (RGDC) and shows the adhesion behavior of cells seeded on these materials. RGDC peptides were first conjugated to a norbornenyl-poly(ethylene oxide) macromonomer (Nb-PEO). Then, functional NPs with a size of ∼300 nm and constituted of polynorbornene core surrounded by poly(ethylene oxide) shell were prepared by ring-opening metathesis polymerization in dispersed medium. The grafting density of these NPs on the titanium surface is up to 2 NPs·μm(-2) (80 pmol of RGDC per cm(-2) of NP surface). Cell adhesion was evaluated using preosteoblast cells (MC3T3-E1). Results of cells cultured for 24 h showed that materials grafted with NPs functionalized with RGDC peptides enhance specific cell adhesion and can create filopodia-like structures among NP sites by stressing the cells.
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Human papillomavirus (HPV) is a sexually transmitted virus that is associated with increased risk of anogenital cancers in immunosuppressed hosts. The behavior of HPV infection is controlled by the systemic immune system response as well... more
Human papillomavirus (HPV) is a sexually transmitted virus that is associated with increased risk of anogenital cancers in immunosuppressed hosts. The behavior of HPV infection is controlled by the systemic immune system response as well as the local tissue immune system to the HPV virus. Individuals with a depressed immune system, either by viral infection (such as human immunodeficiency virus) or by chronic immunosuppressive agents (such as transplant recipients or patients with autoimmune disease) are at an increased risk of HPV-associated malignancies. This article addresses the data and limitations in developing evidence-driven guidelines for cervical cancer screening in immunocompromised women.
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As life expectancy increases, it is imperative that health care providers recognize the importance of safe medication use within an aging geriatric population. Dealing with a cohort that has different biological and medical demands... more
As life expectancy increases, it is imperative that health care providers recognize the importance of safe medication use within an aging geriatric population. Dealing with a cohort that has different biological and medical demands requires pharmacists to pay particular attention to details when treating this subset of individuals. In particular, this manuscript will focus on Alzheimer's disease (AD) and considerations when dealing with new treatment options. The Food and Drug Administration's recent approval of the increased dosage strength, donepezil 23 mg, previously only available in 5 mg and 10 mg strengths, has raised efficacy and safety concerns. Reservations stem from unproven superiority along with an increased incidence of adverse events. The purpose of the manuscript is to provide a brief insight into these concerns and provide readers the knowledge necessary to make a clinically sound decision when treating patients with moderate-to-severe AD.
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To date, RNA interfering molecules have been used to differentiate stem cells on two-dimensional (2D) substrates that do not mimic three-dimensional (3D) microenvironments in the body. Here, in situ forming poly(ethylene glycol) (PEG)... more
To date, RNA interfering molecules have been used to differentiate stem cells on two-dimensional (2D) substrates that do not mimic three-dimensional (3D) microenvironments in the body. Here, in situ forming poly(ethylene glycol) (PEG) hydrogels were engineered for controlled, localized and sustained delivery of RNA interfering molecules to differentiate stem cells encapsulated within the 3D polymer network. RNA interfering molecules were released from the hydrogels in a sustained and controlled manner over the course of 3-6 weeks, and exhibited high bioactivity. Importantly, it was demonstrated that the delivery of siRNA and/or miRNA from the hydrogel constructs enhanced the osteogenic differentiation of encapsulated stem cells. Prolonged delivery of siRNA and/or miRNA from this polymeric scaffold permitted extended regulation of cell behavior, unlike traditional siRNA experiments performed in vitro. This approach presents a powerful new methodology for controlling cell fate, and is...
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Scanning electron microscopy revealed that the rpoS-deficient cells of E. coli K-12 BW25113 (ΔrpoS) increased the number of flagella on the cell surfaces. However, the quantitative analysis of cell colonization showed that the increased... more
Scanning electron microscopy revealed that the rpoS-deficient cells of E. coli K-12 BW25113 (ΔrpoS) increased the number of flagella on the cell surfaces. However, the quantitative analysis of cell colonization showed that the increased number of flagella on ΔrpoS cell surfaces did not cause the enhancement of cell colonization on the surfaces of polyvinyl chloride (PVC), polypropylene (PP) and polystyrene (PS) after 24 h of incubation at 37℃. To facilitate the enhanced expression of curli, the csgA gene was introduced into the ΔrpoS cells. The transformed cells rich in flagella and curli on the cell surfaces were found to make colonies 2-3 times larger than both the wild type and ΔrpoS cells on the PVC, PP and PS surfaces at 37℃. It was thus verified that the reinforcement of csgA gene in the ΔrpoS cells induced the enhanced colonization on the solid surfaces with the increased flagellum and curli expressions.
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During interphase, the spindle assembly factor TPX2 is compartmentalized in the nucleus where its roles remain largely uncharacterized. Recently, we found that TPX2 regulates the levels of serine 139-phosphoryated H2AX (γ-H2AX) at... more
During interphase, the spindle assembly factor TPX2 is compartmentalized in the nucleus where its roles remain largely uncharacterized. Recently, we found that TPX2 regulates the levels of serine 139-phosphoryated H2AX (γ-H2AX) at chromosomal breaks induced by ionizing radiation. Here, we report that TPX2 readily associates with the chromatin in the absence of ionizing radiation. Overexpression of TPX2 alters the DAPI staining pattern of interphase cells and depletion of TPX2 constitutively decreases the levels of histone H4 acetylated at lysine16 (H4K16ac) during G1-phase. Upon ionizing irradiation, this constitutive TPX2 depletion-dependent decrease in H4K16ac levels correlates with increased levels of γ-H2AX. The inversely correlated levels of H4K16ac and γ-H2AX can also be modified by altering the levels of SIRT1, herein identified as a novel protein complex partner of TPX2. Furthermore, we find that TPX2 depletion also interferes with formation of 53BP1 ionizing radiation-induc...
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Research Interests: Rheumatology, Immunology, Osteoarthritis, Prospective studies, Humans, and 20 moreFemale, Predictive Validity, Male, Follow-up studies, Expert Opinion, Clinical Sciences, Aged, Middle Aged, Gold Standard, Longitudinal Studies, Observer Variation, Health Care System, Public health systems and services research, Disease Progression, Sensitivity and Specificity, Graphical Representation, Total Hip-arthroplasty, Predictive value of tests, Random Allocation, and False Positive
As well as catalyzing the conversion of cholesterol to pregnenolone for steroid synthesis, cytochrome P450scc (P450scc) can also metabolize vitamins D2 (D2) and D3 (D3). Two products of D2 metabolism by P450scc, 20-hydroxyvitamin D2 and... more
As well as catalyzing the conversion of cholesterol to pregnenolone for steroid synthesis, cytochrome P450scc (P450scc) can also metabolize vitamins D2 (D2) and D3 (D3). Two products of D2 metabolism by P450scc, 20-hydroxyvitamin D2 and 17,20-dihydroxyvitamin D2, have been identified and shown to exert biological activity on cultured keratinocytes. The aim of this study was to fully characterize the metabolism of D2 by P450scc, including identifying additional products and determining the kinetics of D2 metabolism. Two new products were isolated by reverse-phase high-performance liquid chromatography: a dihydroxy metabolite with a hydroxyl group at C20 plus another unidentified position, and a trihydroxy metabolite identified by NMR as 17,20,24-trihydroxyvitamin D2. Kinetics of D2 metabolism was determined with substrate solubilized by 2-hydroxypropyl-beta-cyclodextrin or incorporated into phospholipid vesicles. In 2-hydroxypropyl-beta-cyclodextrin, D2 was hydroxylated at C20 with a...
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A novel triblock copolymer for use in an injectable pH- and temperature-sensitive hydrogel is synthesized by conjugating poly(amidoamine) (PAA) to poly(ethylene glycol): poly(amidoamine)-poly(ethylene glycol)-poly(amidoamine)... more
A novel triblock copolymer for use in an injectable pH- and temperature-sensitive hydrogel is synthesized by conjugating poly(amidoamine) (PAA) to poly(ethylene glycol): poly(amidoamine)-poly(ethylene glycol)-poly(amidoamine) (PAA-PEG-PAA). The polymer was characterized with (1)H NMR and gel permeation chromatography in the diluents CDCl(3) and CHCl(3), respectively. The PAA block acts as a pH- and temperature-sensitive block. The PAA-PEG-PAA copolymer in aqueous solution (12.5 wt %) underwent a sol-gel transition as a function of pH and temperature. After injection into a rat, the copolymer solution (12.5 wt %) was immediately changed to a gel.
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A series of oligo(amidoamine)s (OAAs) that can be reversibly switched between sol and gel phases upon changes in pH and temperature have been synthesized and characterized. Their viscoelastic properties were significantly increased upon... more
A series of oligo(amidoamine)s (OAAs) that can be reversibly switched between sol and gel phases upon changes in pH and temperature have been synthesized and characterized. Their viscoelastic properties were significantly increased upon increasing the number of methylene groups, implying that viscoelasticity could clearly be tuned at the molecular level.
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Comparing and classifying the three-dimensional (3D) structures of proteins is of crucial importance to molecular biology, from helping to determine the function of a protein to determining its evolutionary relationships. Traditionally,... more
Comparing and classifying the three-dimensional (3D) structures of proteins is of crucial importance to molecular biology, from helping to determine the function of a protein to determining its evolutionary relationships. Traditionally, 3D structures are classified into groups of families that closely resemble the grouping according to their primary sequence. However, significant structural similarities exist at multiple levels between proteins that belong to these different structural families. In this study, we propose a new algorithm, CLICK, to capture such similarities. The method optimally superimposes a pair of protein structures independent of topology. Amino acid residues are represented by the Cartesian coordinates of a representative point (usually the C(α) atom), side chain solvent accessibility, and secondary structure. Structural comparison is effected by matching cliques of points. CLICK was extensively benchmarked for alignment accuracy on four different sets: (i) 953...
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Previous studies have shown that cell cycle proteins such as retinoblastoma protein (pRB) are essential for cell cycle withdrawal in differentiating lens cells. However, little is known about which factors are critical for cell cycle... more
Previous studies have shown that cell cycle proteins such as retinoblastoma protein (pRB) are essential for cell cycle withdrawal in differentiating lens cells. However, little is known about which factors are critical for cell cycle control in the lens epithelial cells. Here we use the K14 promoter to direct expression of E6 and E7, oncogenes from human papillomavirus type 16, which are known to bind and inactivate p53 and pRB, as molecular tools to study cell cycle regulation in the lens epithelium of transgenic mice. Expression of either gene resulted in increased proliferation and apoptosis, and in the case of E6, a unique epithelial phenotype characterized by multilayering and intercellular vacuoles was observed. Lenses from mice expressing E7 mutants, which are defective in inactivating pRB proteins, were normal and the lens phenotype in the E6 mice was p53-independent. Thus, cell proliferation in the lens epithelium is controlled by multiple factors including, but not necessa...
Research Interests: Electron Microscopy, Fluorescence Microscopy, Cell Cycle, Cell Adhesion, Apoptosis, and 15 moreIn Situ Hybridization, Transgenic Mice, Cell Division, Biological Sciences, HUMAN PAPILLOMAVIRUS, Cell Differentiation, Mutation, Mice, Animals, Phenotype, Retinoblastoma, Cell Cycle regulation, Cell Proliferation, Crystallins, and Cell Cycle Control
There is growing evidence for involvement of members of the cyclin-dependent kinase (Cdk) family in neurodegenerative disorders and in apoptotic death of neurons subjected to various insults. After our recent report that a deregulation of... more
There is growing evidence for involvement of members of the cyclin-dependent kinase (Cdk) family in neurodegenerative disorders and in apoptotic death of neurons subjected to various insults. After our recent report that a deregulation of Cdk5 activity by p25 may contribute to pathogenesis of amyotrophic lateral sclerosis (ALS), we further examined the possible involvement of other Cdks in mice expressing a mutant form of superoxide dismutase (SOD1(G37R)) linked to ALS. No substantial changes in Cdk2 or Cdk6 distribution and kinase activities were detected in spinal motor neurons from SOD1(G37R) mice when compared with normal mice. Of particular interest was the upregulation and mislocalization of Cdk4, a regulator of the G1-S checkpoint of the cell cycle, in motor neurons of SOD1(G37R) mice. The increase of Cdk4 activity in SOD1(G37R) mice was associated with an increase in nuclear Cdk4, cyclin D1, its coactivator, and with the abnormal phosphorylation of the retinoblastoma (Rb) pr...
Research Interests: Cell Cycle, Motor neuron, Transgenic Mice, Signal Transduction, Amyotrophic Lateral Sclerosis, and 18 moreHumans, Mice, Animals, Cell Death, The, Phosphorylation, Superoxide Dismutase, Retinoblastoma, Cell nucleus, Anti-Bacterial Agents, Neuronal Death, Cell Cycle regulation, Disease Progression, Amino Acid Substitution Rates, Cell Cycle Proteins, Minocycline, retinoblastoma protein (RB1)., and Neuronal apoptosis
An HPLC method to determine simultaneously ketoconazole and formaldehyde in an anti-dandruff shampoo, originally developed on a long column, was transferred to two short columns with similar stationary phase properties, but with a length... more
An HPLC method to determine simultaneously ketoconazole and formaldehyde in an anti-dandruff shampoo, originally developed on a long column, was transferred to two short columns with similar stationary phase properties, but with a length of at the most 30% of the initial one. Using the conventional column as reference, the fast HPLC methods on the short columns were validated. The validation characteristics consisted of selectivity, linearity range, precision (repeatability and time-different intermediate precision), bias and robustness. For the ketoconazole assay, linearity for peak area was found in the concentration range up to 0.20 mg/ml. For formaldehyde, two calibration ranges (0-10 x 10(-5) and 0-10 x 10(-4)%) were linear, both for peak area and height. The assays for both ketoconazole and formaldehyde in these ranges showed no bias and an acceptable precision, although the precision found with the short columns was slightly worse than with the long one. The robustness tests ...
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The roles of PDZ domain-containing proteins such as Dlg and Scrib have been well described for Drosophila; however, their requirement for mammalian development is poorly understood. Here we show that Dlg, Scrib, MAGI1, MAGI3, and MPDZ are... more
The roles of PDZ domain-containing proteins such as Dlg and Scrib have been well described for Drosophila; however, their requirement for mammalian development is poorly understood. Here we show that Dlg, Scrib, MAGI1, MAGI3, and MPDZ are expressed in the mouse ocular lens. We demonstrate that the increase in proliferation and defects in cellular adhesion and differentiation observed in epithelia of lenses that express E6, a viral oncoprotein that can bind to several PDZ proteins, including the human homologs of Dlg and Scrib, is dependent on E6's ability to bind these proteins via their PDZ domains. Analyses of lenses from mice carrying an insertional mutation in Dlg (dlg(gt)) show increased proliferation and proliferation in spatially inappropriate regions of the lens, a phenotype similar to that of lenses expressing E6. The results from this study indicate that multiple PDZ domain-containing proteins, including Dlg and Scrib, may be required for maintaining the normal pattern...
Research Interests: Developmental Biology, Cellular Biology, Cell Cycle, Membrane Proteins, Molecular Mechanics, and 19 moreTransgenic Mice, Cell Division, Biological Sciences, Cell Differentiation, Molecular and cellular biology, Humans, Mice, Animals, Cell Death, Proteins, Mantle Transition Zone, Retinoblastoma, Epithelial cells, Cell Shape, Cell Cycle regulation, Base Sequence, Crystallins, Cell Cycle Control, and Cell Growth
In invertebrates such as Drosophila melanogaster and Caenorhabditis elegans, the PDZ domain containing proteins, Discs large (Dlg) and Scribble (Scrib), are found localized to specific junctional complexes and have been shown to be... more
In invertebrates such as Drosophila melanogaster and Caenorhabditis elegans, the PDZ domain containing proteins, Discs large (Dlg) and Scribble (Scrib), are found localized to specific junctional complexes and have been shown to be required for establishing and maintaining epithelial cell adhesion, polarity, and proliferation during development. In addition, they are known to be critical for neural development. However, the mechanisms and pathways through which they act in mammalian systems, especially in vivo, are poorly understood. The purpose of this study was to characterize the distribution of Dlg-1 and Scrib in various structures of the mouse eye and the regions where these proteins overlap with known adhesion proteins. Embryos or mouse eyes were embedded, sectioned, subjected to immunofluorescence with antibodies to Dlg-1, Scrib, and E-cadherin, N-cadherin, or ZO-1, and stained sections viewed under confocal microscopy. Dlg-1 and Scrib were found widely distributed throughout...
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We address the problem of predicting solvent accessible surface area (ASA) of amino acid residues in protein sequences, without classifying them into buried and exposed types. A two-stage support vector regression (SVR) approach is... more
We address the problem of predicting solvent accessible surface area (ASA) of amino acid residues in protein sequences, without classifying them into buried and exposed types. A two-stage support vector regression (SVR) approach is proposed to predict real values of ASA from the position-specific scoring matrices generated from PSI-BLAST profiles. By adding SVR as the second stage to capture the influences on the ASA value of a residue by those of its neighbors, the two-stage SVR approach achieves improvements of mean absolute errors up to 3.3%, and correlation coefficients of 0.66, 0.68, and 0.67 on the Manesh dataset of 215 proteins, the Barton dataset of 502 nonhomologous proteins, and the Carugo dataset of 338 proteins, respectively, which are better than the scores published earlier on these datasets. A Web server for protein ASA prediction by using a two-stage SVR method has been developed and is available (http://birc.ntu.edu.sg/~ pas0186457/asa.html).
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A series of novel pH-sensitive triblock copolymers composed of poly(β-amino ester)–poly(ethylene glycol)–poly(β-amino ester) (PAE–PEG–PAE) were synthesized by conjugating poly(β-amino ester) to poly(ethylene glycol). The resulting... more
A series of novel pH-sensitive triblock copolymers composed of poly(β-amino ester)–poly(ethylene glycol)–poly(β-amino ester) (PAE–PEG–PAE) were synthesized by conjugating poly(β-amino ester) to poly(ethylene glycol). The resulting polymers were characterized by 1H and 13C NMR in CDCl3 and gel permeation chromatography in tetrahydrofuran. The concentrated polymer solutions (30wt%) exhibited a gel-to-sol transition in the pH range 6.4–7.8. The gel window spanned physiological
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Peripherin is a type III intermediate filament protein detected in axonal spheroids associated with amyotrophic lateral sclerosis (ALS). The overexpression of peripherin induces degeneration of spinal motor neurons during aging in... more
Peripherin is a type III intermediate filament protein detected in axonal spheroids associated with amyotrophic lateral sclerosis (ALS). The overexpression of peripherin induces degeneration of spinal motor neurons during aging in transgenic mice and in cultured neuronal cells derived from peripherin transgenic embryos. Here, we investigated whether peripherin is a contributor of pathogenesis in mice overexpressing a mutant superoxide dismutase
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Vectors derived from human immunodeficiency virus (HIV) are highly efficient vehicles for in vivo gene de- livery. However, their biosafety is of major concern. Here we exploit the complexity of the HIV genome to pro- vide lentivirus... more
Vectors derived from human immunodeficiency virus (HIV) are highly efficient vehicles for in vivo gene de- livery. However, their biosafety is of major concern. Here we exploit the complexity of the HIV genome to pro- vide lentivirus vectors with novel biosafety features. In addition to the structural genes, HIV contains two regu- latory genes, tat and rev, that are essential
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The cytoskeleton controls the architecture and survival of central nervous system (CNS) neurons by maintaining the stability of axons and dendrites. Although neurofilaments (NFs) constitute the main cytoskeletal network in these... more
The cytoskeleton controls the architecture and survival of central nervous system (CNS) neurons by maintaining the stability of axons and dendrites. Although neurofilaments (NFs) constitute the main cytoskeletal network in these structures, the mechanism that underlies subunit incorporation into filaments remains a mystery. Here we report that NUDEL, a mammalian homologue of the Aspergillus nidulans nuclear distribution molecule NudE, is
Research Interests: Biochemistry, Genetics, Biophysics, Electron Microscopy, Molecular Biology, and 34 moreStem Cells, Migration, MicroRNA, Cancer, Biology, Cell Cycle, Cell Biology, Polymers, DNA damage, Apoptosis, Adhesion, Nature, Cytoskeleton, Neurodegenerative Diseases, Signal Transduction, Transcription, Biological Sciences, RNA interference, Cell line, Cell Differentiation, Mice, Animals, Cell, Central Nervous System, Signalling, Neurons, Actin Cytoskeleton, Chromatin, Aspergillus Nidulans, Mouse Model, Polarity, Disease Progression, Zebrafish, and Protein Transport
In this paper, we propose to use dual-tree complex and double density discrete wavelet transform for extracting mass spectrometry features. Two corresponding procedures are suggested for mass spectrometry classification. Several... more
In this paper, we propose to use dual-tree complex and double density discrete wavelet transform for extracting mass spectrometry features. Two corresponding procedures are suggested for mass spectrometry classification. Several experiments are deployed on two types of MALDI-TOF mass spectra, including stable spectra and noisy spectra. The classification results show that our proposed procedures not only obtain better performance than
Research Interests: Data Mining, Mass Spectrometry, Cancer, Support Vector Machines, Molecular Biophysics, and 10 moreFeature Extraction, Proteins, Support vector machine, Complex wavelet transform, Ionization, Discrete wavelet transform, Gaussian noise, Mass Spectroscopy, Discrete Wavelet Transforms, and Cyclic Redundancy Check
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High-level electronic structure calculations have been used to map out the relevant portions of the potential energy surfaces for the release of H2 from dimers of ammonia borane, BH3NH3 (AB). Using the correlation-consistent aug-cc-pVTZ... more
High-level electronic structure calculations have been used to map out the relevant portions of the potential energy surfaces for the release of H2 from dimers of ammonia borane, BH3NH3 (AB). Using the correlation-consistent aug-cc-pVTZ basis set at the second-order perturbation MP2 level, geometries of stationary points were optimized. Relative energies were computed at these points using coupled-cluster CCSD(T) theory with the correlation-consistent basis sets at least up to the aug-cc-pVTZ level and in some cases extrapolated to the complete basis set limit. The results show that there are a number of possible dimers involving different types of hydrogen-bonded interactions. The most stable gaseous phase (AB)2 dimer results from a head-to-tail cyclic conformation and is stabilized by 14.0 kcal/mol with respect to two AB monomers. (AB)2 can generate one or two H2 molecules via several direct pathways with energy barriers ranging from 44 to 50 kcal/mol. The diammoniate of diborane ion pair isomer, [BH4-][NH3BH2NH3+] (DADB), is 10.6 kcal/mol less stable than (AB)2 and can be formed from two AB monomers by overcoming an energy barrier of approximately 26 kcal/mol. DADB can also be generated from successive additions of two NH3 molecules to B2H6 and from condensation of AB with separated BH3 and NH3 molecules. The pathway for H2 elimination from DADB is characterized by a smaller energy barrier of 20.1 kcal/mol. The alternative ion pair [NH4+][BH3NH2BH3-] is calculated to be 16.4 kcal/mol above (AB)2 and undergoes H2 release with an energy barrier of 17.7 kcal/mol. H2 elimination from both ion pair isomers yields the chain BH3NH2BH2NH3 as product. Our results suggest that the neutral dimer will play a minor role in the release of H2 from ammonia borane, with a dominant role from the ion pairs as observed experimentally in ionic liquids and the solid state.
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The potential energy surface (PES) of a [C2, H2, N, O] system in its electronic doublet ground state has been investigated using density functional theory method, at B3LYP/6-311++ G (3df, 2p)//B3LYP/6-311++ G (d, p) level. Twelve stable... more
The potential energy surface (PES) of a [C2, H2, N, O] system in its electronic doublet ground state has been investigated using density functional theory method, at B3LYP/6-311++ G (3df, 2p)//B3LYP/6-311++ G (d, p) level. Twelve stable intermediate radicals ...