72 results match your criteria: "Centre for Life Sciences CeLS.[Affiliation]"

Multivalent transition metal oxides (MOx ) containing redox centers which can theoretically accept more than one electron have been suggested as promising anode materials for high-performance lithium ion batteries (LIBs). The Li-storage mechanism of these oxides is suggested to involve an unusual conversion reaction leading to the formation of metallic nanograins and Li2 O; however, a full-scale conversion reaction is seldom observed in molybdenum dioxide (MoO2 ) at room temperature due to slow kinetics. Herein, a full-scale multi-electron conversion reaction, leading to a high reversible capacity (974 mA h g(-1) charging capacity at 60 mA g(-1) ) in LIBs, is realized in a hybrid consisting of reduced graphene oxide (rGO) sheet-wrapped MoO2 porous nanobelts (rGO/MoO2 NBs).

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Asymmetric Michael addition of α-fluoro-α-nitro esters to nitroolefins: towards synthesis of α-fluoro-α-substituted amino acids.

Org Biomol Chem

February 2015

Graduate School for Integrative Sciences & Engineering (NGS), Centre for Life Sciences (CeLS), National University of Singapore, #05-01, 28 Medical Drive, 117456 Singapore.

α-Fluoro-α-nitro esters were used as reaction partners in Michael addition to nitroalkenes, and the products were obtained in excellent chemical yields and with high enantioselectivities. Moreover, α-fluoro-α-amino ester with a quaternary α-carbon was prepared for the first time.

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HepaRG culture in tethered spheroids as an in vitro three-dimensional model for drug safety screening.

J Appl Toxicol

August 2015

Department of Bioengineering, National University of Singapore, Block EA, #03-12, 9 Engineering Drive 1, Singapore, 117576, Singapore.

Conventional two-dimensional (2D) monolayer cultures of HepaRG cells allow in vitro maintenance of many liver-specific functions. However, cellular dedifferentiation and functional deterioration over an extended culture period in the conventional 2D HepaRG culture have hampered its applications in drug testing. To address this issue, we developed tethered spheroids of HepaRG cells on Arg-Gly-Asp (RGD) and galactose-conjugated substratum with an optimized hybrid ratio as an in vitro three-dimensional (3D) human hepatocyte model.

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Drug permeation through skin is inversely correlated with carrier gel rigidity.

Mol Pharm

February 2015

NUS Graduate School for Integrative Sciences and Engineering, Centre for Life Sciences (CeLS), #05-01, 28 Medical Drive, 117456, Singapore.

Controlled release plays an essential role in formulating topical and transdermal drug delivery systems. In this study, we correlated the skin permeation of Sesamin, a lipophilic drug, with the rheological properties of two different organogel carriers, i.e.

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Electronically transparent graphene barriers against unwanted doping of silicon.

ACS Appl Mater Interfaces

November 2014

NUS Graduate School for Integrative Sciences and Engineering, Centre for Life Sciences (CeLS), 28 Medical Drive, Singapore 117597, Singapore.

Diffusion barriers prevent materials from intermixing (e.g., undesired doping) in electronic devices.

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Asymmetric Michael addition of α-fluoro-α-nitroalkanes to nitroolefins: facile preparation of fluorinated amines and tetrahydropyrimidines.

Chem Commun (Camb)

August 2014

Graduate School for Integrative Sciences & Engineering (NGS), Centre for Life Sciences (CeLS), National University of Singapore, #05-01, 28 Medical Drive, Singapore 117456.

An asymmetric Michael addition of α-fluoro-α-nitroalkanes to nitroolefins was developed, and the products were obtained in good chemical yields and with high stereoselectivities. Highly functionalized adducts provided ready access to fluorinated amines and tetrahydropyrimidines in an optically enriched form.

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Lack of blinding of outcome assessors in animal model experiments implies risk of observer bias.

J Clin Epidemiol

September 2014

The Nordic Cochrane Centre, Rigshospitalet, Department 7811, Blegdamsvej 9, 2100 Copenhagen Ø, Denmark.

Objectives: To examine the impact of not blinding outcome assessors on estimates of intervention effects in animal experiments modeling human clinical conditions.

Study Design And Setting: We searched PubMed, Biosis, Google Scholar, and HighWire Press and included animal model experiments with both blinded and nonblinded outcome assessors. For each experiment, we calculated the ratio of odds ratios (ROR), that is, the odds ratio (OR) from nonblinded assessments relative to the corresponding OR from blinded assessments.

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An alternative antimalarial pathway of an 'outdated' drug, chloroquine (CQ), may facilitate its return to the shrinking list of effective antimalarials. Conventionally, CQ is believed to interfere with hemozoin formation at nanomolar concentrations, but resistant parasites are able to efflux this drug from the digestive vacuole (DV). However, we show that the DV membrane of both resistant and sensitive laboratory and field parasites is compromised after exposure to micromolar concentrations of CQ, leading to an extrusion of DV proteases.

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Mitochondrial ROS and involvement of Bcl-2 as a mitochondrial ROS regulator.

Mitochondrion

November 2014

Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, 10 Medical Drive, Clinical Research Center, #04-25, Singapore 117597, Singapore; NUS Graduate School for Integrative Sciences and Engineering, Centre for Life Sciences (CeLS), #05-01, 28 Medical Drive, Singapore 117576, Singapore; Cancer and Stem Cell Biology Program, Duke-NUS Graduate Medical School, Singapore; Singapore-MIT Alliance, Singapore; National University Cancer Institute, Singapore. Electronic address:

Mitochondria are the major intracellular source of reactive oxygen species (ROS). While excessive mitochondrial ROS (mitoROS) production induces cell injury and death, there is accumulating evidence that non-toxic low levels of mitoROS could serve as important signaling molecules. Therefore, maintenance of mitoROS at physiological levels is crucial for cell homeostasis as well as for survival and proliferation.

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Microscopy techniques in flavivirus research.

Micron

April 2014

Flavivirology Laboratory, Department of Microbiology, Yong Loo Lin School of Medicine, National University Health System, National University of Singapore, 5 Science Drive 2, MD4 Level 3, Singapore 117545, Singapore; NUS Graduate School for Integrative Sciences and Engineering, National University of Singapore, Centre for Life Sciences (CeLS), 28 Medical Drive, #05-01, Singapore 117456, Singapore; Electron Microscopy Unit, Yong Loo Lin School of Medicine, National University Health System, National University of Singapore, 12 Medical Drive, MD5, Singapore 117597, Singapore. Electronic address:

The Flavivirus genus is composed of many medically important viruses that cause high morbidity and mortality, which include Dengue and West Nile viruses. Various molecular and biochemical techniques have been developed in the endeavour to study flaviviruses. However, microscopy techniques still have irreplaceable roles in the identification of novel virus pathogens and characterization of morphological changes in virus-infected cells.

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In vivo biodistribution of platinum-based drugs encapsulated into multi-walled carbon nanotubes.

Nanomedicine

October 2014

Department of Pharmacy, National University of Singapore, Science Drive 2, Singapore; NUS Graduate School for Integrative Sciences and Engineering, Centre for Life Sciences (CeLS), 28 Medical Drive, Singapore; NUSNNI-NanoCore, National University of Singapore, T-Lab Level 11, 5A Engineering Drive 1, Singapore. Electronic address:

Carbon nanotubes (CNTs) are promising drug delivery systems due to their external functionalizable surface and their hollowed cavity that can encapsulate several bioactive molecules. In this study, the chemotherapeutic drug cisplatin or an inert platinum(IV) complex were entrapped inside functionalized-multi-walled-CNTs and intravenously injected into mice to investigate the influence of CNTs on the biodistribution of Pt-based molecules. The platinum levels in vital organs suggested that functionalized-CNTs did not affect cisplatin distribution, while they significantly enhanced the accumulation of Pt(IV) sample in some tissues (e.

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Bacterial imaging with photostable upconversion fluorescent nanoparticles.

Biomaterials

March 2014

Graduate School for Integrative Sciences and Engineering, National University of Singapore, Centre for Life Sciences (CeLS), #05-01, 28 Medical Drive, Singapore 117456, Singapore; Department of Biomedical Engineering, Faculty of Engineering, National University of Singapore, Block EA #03-12, 9 Engineering Drive 1, Singapore 117575, Singapore. Electronic address:

Autofluorescence, photodamage and photobleaching are often encountered when using downconverting fluorophores and fluorescent proteins for bacteria labeling. These caveats represent a serious limitation when trying to map bacteria dissemination for prolonged periods. Upconversion nanoparticles (UCNs), which are able to convert low energy near-infrared (NIR) excitation light into higher energy visible or NIR light, can address these limitations.

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Among the arsenal of nano-materials, carbon nanotubes (CNTs) are becoming more prominent due to favorable attributes including their unique shape, which promotes cellular-uptake, and large aspect-ratio that facilitates functionalization of bioactive molecules on their surface. In this study, multi-walled carbon nanotubes (MWCNTs) were functionalized with either mitochondrial-targeting fluorescent rhodamine-110 (MWCNT-Rho) or non-targeting fluorescein (MWCNT-Fluo). Despite structural similarities, MWCNT-Rho associated well with mitochondria (ca.

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Fe-doped MnxOy with hierarchical porosity as a high-performance lithium-ion battery anode.

Adv Mater

September 2013

Department of Chemical and Biomolecular Engineering, National University of Singapore, 119260, Singapore; Graduate School for Integrative Sciences & Engineering (NGS), Centre for Life Sciences (CeLS), 117456, Singapore.

Fe-doped Mnx Oy with hierarchical porosity is prepared from a nanocasting technique using amine-functionalized bromomethylated poly (2,6-dimethyl-1,4-phenylene oxide) (BPPO) membranes as the sacrificial template. The synergistic coupling of a percolating macroporous network, uniformly distributed mesopores, and optimal iron doping is used to improve the electronic and ionic wirings of manganese oxides for Li(+) storage via the conversion reaction. Very impressive Li(+) storage capabilities are shown.

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The medial prefrontal cortex (mPFC) in the rat has been implicated in a variety of cognitive processes, including working memory and expression of fear memory. We investigated the inputs from a brain stem nucleus, the nucleus incertus (NI), to the prelimbic area of the mPFC. This nucleus strongly expresses corticotropin-releasing factor type 1 (CRF1 ) receptors and responds to stress.

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Biomimetic nanostructured materials: potential regulators for osteogenesis?

Ann Acad Med Singap

May 2011

National University of Singapore (NUS) Graduate School (NGS) for Integrative Sciences and Engineering, Centre for Life Sciences (CeLS).

Article Synopsis
  • - Nanostructured materials are being developed due to improved fabrication techniques and their unique properties, which closely resemble the natural extracellular matrix (ECM) found in the body.
  • - These materials create artificial environments that can influence the behavior of mesenchymal stem cells (MSCs), particularly in guiding their differentiation into bone-forming cells (osteoblasts) without needing soluble factors.
  • - Incorporating components like collagen and hydroxyapatite into these nanostructures enhances their effectiveness in mimicking native bone, making them promising candidates for scaffolds used in bone regeneration therapies.
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Nanoparticle fractionation using an aligned carbon nanotube array.

Nanotechnology

July 2010

NUS Graduate School for Integrative Sciences and Engineering (NGS), Centre for Life Sciences (CeLS), #05-01, 28 Medical Drive, 117456, Singapore.

A technique utilizing the capillary assisted sieving capability of carbon nanotubes (CNTs) to achieve fractionation of nanoparticles of small size distribution is presented. By dipping aligned CNT arrays into a solution comprising different sized quantum dots (QDs), size-selective gradient decoration of QDs onto CNTs is achieved. The fractionating capability of CNTs is also demonstrated for poly-dispersed manganese doped zinc sulfide nanoparticles and QDs of varying sizes and chemical compositions, which we attribute to the size-selective sieving effect of CNTs.

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Microfabricated systems provide an excellent platform for the culture of cells, and are an extremely useful tool for the investigation of cellular responses to various stimuli. Advantages offered over traditional methods include cost-effectiveness, controllability, low volume, high resolution, and sensitivity. Both biocompatible and bio-incompatible materials have been developed for use in these applications.

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Effect of voluntary running on adult hippocampal neurogenesis in cholinergic lesioned mice.

BMC Neurosci

June 2009

Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Centre for Life Sciences (CeLS), Level 4, 28 Medical Drive, 117456, Singapore.

Background: Cholinergic neuronal dysfunction of the basal forebrain is observed in patients with Alzheimer's disease and dementia, and has been linked to decreased neurogenesis in the hippocampus, a region involved in learning and memory. Running is a robust inducer of adult hippocampal neurogenesis. This study aims to address the effect of running on hippocampal neurogenesis in lesioned mice, where septohippocampal cholinergic neurones have been selectively eliminated in the medial septum and diagonal band of Broca of the basal forebrain by infusion of mu-p75-saporin immunotoxin.

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Retroviruses human immunodeficiency virus and murine leukemia virus are enriched in phosphoinositides.

J Virol

November 2008

Centre for Life Sciences (CeLS), Yong Loo Lin School of Medicine, National University of Singapore, 28 Medical Drive, Level 04-21, Singapore 117607, Singapore.

Retroviruses acquire a lipid envelope during budding from the membrane of their hosts. Therefore, the composition of this envelope can provide important information about the budding process and its location. Here, we present mass spectrometry analysis of the lipid content of human immunodeficiency virus type 1 (HIV-1) and murine leukemia virus (MLV).

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Dendrimer hydrazides as multivalent transient inter-cellular linkers.

Biomaterials

September 2008

Institute of Bioengineering and Nanotechnology, A*STAR, The Nanos, #04-01, 31 Biopolis Way, Singapore 138669, Singapore; NUS Graduate School for Integrative Sciences and Engineering, Centre for Life Sciences (CeLS), #05-01, 28 Medical Drive, Singapore 117456, Singapore; Graduate Program in Bioengineering, Centre for Life Sciences (CeLS), #05-01, 28 Medical Drive, Singapore 117456, Singapore; Department of Physiology, Yong Loo Lin School of Medicine, #03-03, 2 Medical Drive, Singapore 117597, Singapore; Singapore-MIT Alliance, E4-04-10, 4 Engineering Drive 3, Singapore 117576, Singapore; NUS Tissue-Engineering Programme, DSO Laboratories, National University of Singapore, Singapore 117597, Singapore; Department of Haematology-Oncology, National University Hospital, Singapore 119074, Singapore.

Three-dimensional (3D) multi-cellular aggregates (MCAs), as a model scaffold-free tissue construct, are useful for engineering cell-dense and matrix-poor tissues for repair and regeneration applications. To facilitate rapid MCA formation with high degrees of linker consistency and performance, we synthesized a class of dendrimer hydrazides with 8, 16 and 32 arms that can react with the aldehyde on the modified cell surfaces to form MCAs. DAB-AM-16 hydrazide with 32 arms demonstrated the best cell aggregation ability as compared to the dendrimer hydrazides with fewer arms, facilitating MCA formation at lower linker concentrations, minimizing cytotoxicity.

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Nanofiber patent landscape.

Recent Pat Nanotechnol

June 2009

National University of Singapore (NUS) Graduate Programme in Bioengineering NUS Graduate School (NGS) for Integrative Sciences and Engineering, Centre for Life Sciences (CeLS) #05-01, 28 Medical Drive Singapore 117456.

Despite the large number of publications in peer review literature in the field of nanofibers, there is still uncertainty as to what aspects of these research results have commercial applications. In an effort to better understand the technological progress made in the field of nanofibers, we surveyed the patents issued in the United States from 1976 up to end 2006. The present review will provide an overall view of the current patent landscape including trends and key applications.

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