1
|
Chang B, Goff A, Sicher I, Loo J, Dunn T, Clary N, Zamarayeva A, Calero-Garcia M. Transfecting aß T cells with CRISPR-Cas9 RNP using a novel microfluidic platform. Cytotherapy 2021. [DOI: 10.1016/s1465324921005302] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
|
2
|
Loo J, Kwok HC, Leung CCH, Wu SY, Law ILG, Cheung YK, Cheung YY, Chin ML, Kwan P, Hui M, Kong SK, Ho HP. Sample-to-answer on molecular diagnosis of bacterial infection using integrated lab--on--a--disc. Biosens Bioelectron 2017; 93:212-219. [PMID: 27660018 DOI: 10.1016/j.bios.2016.09.001] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2016] [Revised: 08/27/2016] [Accepted: 09/01/2016] [Indexed: 12/25/2022]
Abstract
Sepsis by bacterial infection causes high mortality in patients in intensive care unit (ICU). Rapid identification of bacterial infection is essential to ensure early appropriate administration of antibiotics to save lives of patients, yet the present benchtop molecular diagnosis is time-consuming and labor-intensive, which limits the treatment efficiency especially when the number of samples to be tested is extensive. Therefore, we hereby report a microfluidic platform lab-on-a-disc (LOAD) to provide a sample-to-answer solution. Our LOAD customized design of microfluidic channels allows automation to mimic sequential analytical steps in benchtop environment. It relies on a simple but controllable centrifugation force for the actuation of samples and reagents. Our LOAD system performs three major functions, namely DNA extraction, isothermal DNA amplification and real-time signal detection, in a predefined sequence. The disc is self-contained for conducting sample heating with chemical lysis buffer and silica microbeads are employed for DNA extraction from clinical specimens. Molecular diagnosis of specific target bacteria DNA sequences is then performed using a real-time loop-mediated isothermal amplification (RT-LAMP) with SYTO-9 as the signal reporter. Our LOAD system capable of bacterial identification of Mycobacterium tuberculosis (TB) and Acinetobacter baumanii (Ab) with the detection limits 103cfu/mL TB in sputum and 102cfu/mL Ab in blood within 2h after sample loading. The reported LOAD based on an integrated approach should address the growing needs for rapid point-of-care medical diagnosis in ICU.
Collapse
Affiliation(s)
- J Loo
- Biochemistry Programme, School of Life Sciences, The Chinese University of Hong Kong, Shatin, N.T., Hong Kong; Department of Electronic Engineering, The Chinese University of Hong Kong, Shatin, N.T., Hong Kong
| | - H C Kwok
- Department of Electronic Engineering, The Chinese University of Hong Kong, Shatin, N.T., Hong Kong
| | - C C H Leung
- Department of Anaesthesia and Intensive Care, The Chinese University of Hong Kong, Shatin, N.T., Hong Kong
| | - S Y Wu
- Department of Electronic Engineering, The Chinese University of Hong Kong, Shatin, N.T., Hong Kong
| | - I L G Law
- Biochemistry Programme, School of Life Sciences, The Chinese University of Hong Kong, Shatin, N.T., Hong Kong
| | - Y K Cheung
- Department of Medicine and Therapeutics, The Chinese University of Hong Kong, Shatin, N.T., Hong Kong
| | - Y Y Cheung
- Department of Microbiology, The Chinese University of Hong Kong, Shatin, N.T., Hong Kong
| | - M L Chin
- Department of Microbiology, The Chinese University of Hong Kong, Shatin, N.T., Hong Kong
| | - P Kwan
- Department of Medicine and Therapeutics, The Chinese University of Hong Kong, Shatin, N.T., Hong Kong
| | - M Hui
- Department of Microbiology, The Chinese University of Hong Kong, Shatin, N.T., Hong Kong
| | - S K Kong
- Biochemistry Programme, School of Life Sciences, The Chinese University of Hong Kong, Shatin, N.T., Hong Kong
| | - H P Ho
- Department of Electronic Engineering, The Chinese University of Hong Kong, Shatin, N.T., Hong Kong.
| |
Collapse
|
3
|
Loo J. SY03-2-6 * WHO-ISAM FELLOWSHIP TREATMENTS IN ASIA AND PHENOMENOLOGICAL ANALYSIS OF THE LIVED EXPERIENCE OF RECOVERING GAMBLERS IN MALAYSIA. Alcohol Alcohol 2014. [DOI: 10.1093/alcalc/agu052.21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
|
4
|
Hylton NP, Li XF, Giannini V, Lee KH, Ekins-Daukes NJ, Loo J, Vercruysse D, Van Dorpe P, Sodabanlu H, Sugiyama M, Maier SA. Loss mitigation in plasmonic solar cells: aluminium nanoparticles for broadband photocurrent enhancements in GaAs photodiodes. Sci Rep 2013; 3:2874. [PMID: 24096686 PMCID: PMC3791440 DOI: 10.1038/srep02874] [Citation(s) in RCA: 109] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2013] [Accepted: 09/18/2013] [Indexed: 12/21/2022] Open
Abstract
We illustrate the important trade-off between far-field scattering effects, which have the potential to provide increased optical path length over broad bands, and parasitic absorption due to the excitation of localized surface plasmon resonances in metal nanoparticle arrays. Via detailed comparison of photocurrent enhancements given by Au, Ag and Al nanostructures on thin-film GaAs devices we reveal that parasitic losses can be mitigated through a careful choice of scattering medium. Absorption at the plasmon resonance in Au and Ag structures occurs in the visible spectrum, impairing device performance. In contrast, exploiting Al nanoparticle arrays results in a blue shift of the resonance, enabling the first demonstration of truly broadband plasmon enhanced photocurrent and a 22% integrated efficiency enhancement.
Collapse
Affiliation(s)
- N P Hylton
- Department of Physics, Imperial College London, London SW7 2AZ, United Kingdom
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
5
|
Van Meerbergen B, Jans K, Loo J, Reekmans G, Braeken D, Seon-Ah C, Bonroy K, Maes G, Borghs G, Engelborghs Y, Annaert W, Bartic C. Peptide-functionalized microfabricated structures for improved on-chip neuronal adhesion. Annu Int Conf IEEE Eng Med Biol Soc 2009; 2008:1833-6. [PMID: 19163039 DOI: 10.1109/iembs.2008.4649536] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Extracellular, high signal-to-noise ratio recordings from electrogenic cells require a tight coupling between the cellular membrane and the recording electrode. Self assembled monolayers (SAMs) of alkanethiols functionalized with peptides were used in combination with micro- and nano-structured features on the sensor surface. This combination of surface chemistry and topography triggers a phagocytosis-like engulfment and ensures tight coupling. In this paper we report the results concerning usage of different SAMs and the influence of the peptide concentration towards cell adhesion and outgrowth. Later on, the optimized peptide functionalized SAMs were applied on micro- and nano-structured sensor surfaces. As a result, phagocytosis-like events could be shown using focused ion beam SEM and confocal fluorescence imaging.
Collapse
Affiliation(s)
- B Van Meerbergen
- Dept. of Chemistry of the KU Leuven, Flemish Institute of Biotechnology (VIB), Belgium.
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
6
|
Chong SC, Loo J, Lee PS, Ma J. Biomimetic processing of bioactive interface on silicon substrates. J Biomed Mater Res B Appl Biomater 2008; 85:368-77. [DOI: 10.1002/jbm.b.30955] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
|
7
|
Feng MR, Loo J, Wright J. Disposition of the antipsychotic agent CI-1007 in rats, monkeys, dogs, and human cytochrome P450 2D6 extensive metabolizers. Species comparison and allometric scaling. Drug Metab Dispos 1998; 26:982-8. [PMID: 9763403] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023] Open
Abstract
The disposition of CI-1007 (I), an antipsychotic dopamine agonist, was studied after iv or po administration to rats, monkeys, and dogs and po administration to human cytochrome P450 2D6 extensive metabolizers (EMs). I was extensively metabolized after po administration, with high hepatic clearance (CL) values and negligible urinary excretion. Values for systemic plasma CL (28-40 ml/min/kg) suggested hepatic plasma flow-limited CL. The oral CL of I was similar among the species. Strong correlation was achieved in interspecies scaling for CL. After oral administration of [14C]I, the major route of 14C elimination in rats was in the bile (64%), followed by feces (29%) and urine (3.2%). Fecal excretion (64%) was the major route of 14C elimination in monkeys, followed by urine (14%). Three hydroxy metabolites, i.e. PD 147693 (II), PD 149394 (III), and PD 155144 (IV), and two sulfates, i.e. PD 163637 (VI) and PD 163639 (VIII), were identified in monkey plasma, urine, or feces. VIII was the major metabolite excreted in monkey urine, and VI was the major component in feces. Trace amounts of II, VI, and VIII were detected in the plasma and urine of human EMs but not in rats or dogs. II is an active metabolite that was present in all species. After oral administration, observed maximal plasma concentration and AUC values for II were higher than the corresponding values for I in dog plasma, approximately 20-40% of the values for I in monkeys and human EMs, and <5% of the values for I in rat plasma. Although the metabolic profiles differ among species, strong correlation was achieved in allometric scaling because the elimination of I from the body is mainly limited by hepatic blood flow.
Collapse
Affiliation(s)
- M R Feng
- Parke-Davis Pharmaceutical Research, Division of Warner-Lambert Company, Ann Arbor, MI 48105, USA
| | | | | |
Collapse
|
8
|
Domagala JM, Gogliotti R, Sanchez JP, Stier MA, Musa K, Song Y, Loo J, Reily M, Tummino P, Harvey P, Hupe D, Sharmeen L, Mack D, Scholten J, Saunders J, McQuade T. 2,2'-Dithiobisbenzamides and 2-benzisothiazolones, two new classes of antiretroviral agents: SAR and mechanistic considerations. Drug Des Discov 1997; 15:49-61. [PMID: 9332831] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Substituted 2,2'-dithiobisbenzamides and 2-benzisothiazolones were prepared and shown to possess low microM activity with high therapeutic indices against HIV-1, HIV-2 and SIV in cell culture. The mechanism of antiviral action was determined to be directed toward the nucleocapsid protein (NCp7), which contains two zinc fingers and plays vital roles in the viral life cycle. The "active sulfides" of this study cause the extrusion of zinc from these zinc fingers. Structure-activity relationships of the 2,2'-dithiobisbenzamides reveal that the disulfide bond and the ortho benzamide functional groups are essential for activity, with the best compounds having a carboxylic acid, carboxamide, or sulfonamide substituent. The 2-benzisothiazolones are formed from the disulfides both chemically and in vivo and their SAR mimics that of the 2,2'-dithiobisbenzamides. The antiviral activity of the disulfides may require cyclization to the isothiazolones. Two agents, PD 159206 and PD 161374, which showed good antiviral activity, physical properties, and excellent pharmacokinetics in mice, were selected for advanced studies.
Collapse
Affiliation(s)
- J M Domagala
- Department of Chemistry, Parke Davis Pharmaceutical Research, Division of Warner Lambert Company, Ann Arbor, Michigan 48105, USA
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
9
|
Fink HJ, Loo J, Roberts SM. Superconducting microcircuit and fluxoid quantization: A new quantum interferometer. Phys Rev B Condens Matter 1988; 37:5050-5057. [PMID: 9943680 DOI: 10.1103/physrevb.37.5050] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/11/2023]
|
10
|
Cheung F, Wong PY, Loo J, Cole EH, Levy GA. Identification of cyclosporine metabolites in human bile, blood, and urine by high-performance liquid chromatography/radioimmunoassay/fast atomic bombardment mass spectroscopy. Transplant Proc 1988; 20:602-8. [PMID: 3284109] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Affiliation(s)
- F Cheung
- Department of Medicine, University of Toronto, Canada
| | | | | | | | | |
Collapse
|
11
|
Loo J, Brune K. Book reviews. Ann Hematol 1987. [DOI: 10.1007/bf00320572] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/03/2023]
|
12
|
Loo J. 123. Die medkament�se Therapie der tiefen Venenthrombose. Langenbecks Arch Surg 1986. [DOI: 10.1007/bf01274441] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
|
13
|
Loo J. [The children's charter]. Hu Li Za Zhi 1976; 23:50-1. [PMID: 1051815] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
|
14
|
Lijinsky W, Keefer L, Loo J, Ross AE. Studies of alkylation of nucleic acids in rats by cyclic nitrosamines. Cancer Res 1973; 33:1634-41. [PMID: 4721226] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
|
15
|
Lijinsky W, Garcia H, Keefer L, Loo J, Ross AE. Carcinogenesis and alkylation of rat liver nucleic acids by nitrosomethylurea and nitrosoethylurea administered by intraportal injection. Cancer Res 1972; 32:893-7. [PMID: 5017739] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
|
16
|
Keefer LK, Wallcave L, Loo J, Peterson RS. Analysis of mixtures of isomeric polynuclear hydrocarbons by nuclear magnetic resonance spectrometry methylated derivatives of anthracene, benz(a)anthracene, benzo(c)phenanthrene, and pyrene. Anal Chem 1971; 43:1411-6. [PMID: 5135199 DOI: 10.1021/ac60305a010] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
|
17
|
|
18
|
|
19
|
|