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The ability of a serotype M1 strain of Streptococcus pyogenes to efficiently invade A549 human lung epithelial cells was previously shown to be dependent on bacterial exposure to human or bovine serum proteins or synthetic peptides... more
The ability of a serotype M1 strain of Streptococcus pyogenes to efficiently invade A549 human lung epithelial cells was previously shown to be dependent on bacterial exposure to human or bovine serum proteins or synthetic peptides containing the sequence RGD. In this study, stimulation by invasion agonists was determined to be dependent on expression of the streptococcal cell surface protein, M1. Fetal bovine serum (FBS), fibronectin (Fn), the extracellular matrix protein laminin (Lm), and RGD-containing peptides were tested for their abilities to promote epithelial cell invasion and adherence by isogenic M1 + and M1 − strains of S. pyogenes . In the absence of an agonist, invasion and adherence were comparable for the two bacterial strains. FBS, Fn, and Lm stimulated invasion of the M1 + strain as much as 70-fold but failed to significantly affect invasion by the M1 − mutant. Adherence of the wild-type strain was stimulated by these same agonists. Epithelial cell adherence by the ...
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Microbiology, Biology, Cell Adhesion, Medicine, Extracellular Matrix, and 15 moreBiological Sciences, Internalization, Humans, Gram Positive, Lung, Integrins, Fetal Bovine Serum, Fibronectin, Epithelial cells, Ligands, Integrin, Extracellular Matrix Proteins, Host Defense, Laminin, and Medical and Health Sciences
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Chemistry, Asthma, Cell Biology, Medicine, Signal Transduction, and 14 moreHumans, Smooth muscle, Muscle, Pharmacology and Clinical pharmacy, Phosphorylation, Cells, Receptor, Muscle contraction, Airway Obstruction, RhoA, Cultured, Phosphatidylinositol 3-KINASE, Pharmacology and pharmaceutical sciences, and smooth
Chronic obstructive pulmonary disease (COPD) is a major cause of morbidity and mortality. Cigarette smoke (CS) drives disease development and progression. The epithelial barrier is damaged by CS with increased monolayer permeability.... more
Chronic obstructive pulmonary disease (COPD) is a major cause of morbidity and mortality. Cigarette smoke (CS) drives disease development and progression. The epithelial barrier is damaged by CS with increased monolayer permeability. However, the molecular changes that cause this barrier disruption and the interaction between adhesion proteins and the cytoskeleton are not well defined. We hypothesized that CS alters monolayer integrity by increasing cell contractility and decreasing cell adhesion in epithelia. Normal human airway epithelial cells and primary COPD epithelial cells were exposed to air or CS, and changes measured in protein levels. We measured the cortical tension of individual cells and the stiffness of cells in a monolayer. We confirmed that the changes in acute and subacute in vitro smoke exposure reflect protein changes seen in cell monolayers and tissue sections from COPD patients. Epithelial cells exposed to repetitive CS and those derived from COPD patients have...
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Physiology, Chemistry, Cell Adhesion, Cell Biology, Medicine, and 15 moreCytoskeleton, Humans, COPD, Female, Male, Cell Death, Medical Physiology, Aged, Middle Aged, Epithelial cells, Adherens junctions, Biomechanical Phenomena, Cadherins, Cell membrane permeability, and Pulmonary Disease Chronic Obstructive
A defining hallmark of primary and metastatic cancers is the migration and invasion of malignant cells. These invasive properties involve altered dynamics of the cytoskeleton and one of its major structural components β-actin. Here we... more
A defining hallmark of primary and metastatic cancers is the migration and invasion of malignant cells. These invasive properties involve altered dynamics of the cytoskeleton and one of its major structural components β-actin. Here we identify AIM1 (absent in melanoma 1) as an actin-binding protein that suppresses pro-invasive properties in benign prostate epithelium. Depletion of AIM1 in prostate epithelial cells increases cytoskeletal remodeling, intracellular traction forces, cell migration and invasion, and anchorage-independent growth. In addition, decreased AIM1 expression results in increased metastatic dissemination in vivo. AIM1 strongly associates with the actin cytoskeleton in prostate epithelial cells in normal tissues, but not in prostate cancers. In addition to a mislocalization of AIM1 from the actin cytoskeleton in invasive cancers, advanced prostate cancers often harbor AIM1 deletion and reduced expression. These findings implicate AIM1 as a key suppressor of invasi...
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In this paper, the development and implementation of a direct-coupled building emulator for a building energy management and control system (EMCS) is presented. The building emulator consists of a microcomputer and a computer model of an... more
In this paper, the development and implementation of a direct-coupled building emulator for a building energy management and control system (EMCS) is presented. The building emulator consists of a microcomputer and a computer model of an air-conditioning system implemented in a modular dynamic simulation software package for direct-coupling to an EMCS, without using analog-to-digital and digital-to-analog converters. The building emulator can be used to simulate in real time the behavior of the air-conditioning system under a given operating environment and subject to a given usage pattern. Software modules for data communication, graphical display, dynamic data exchange, and synchronization of simulation outputs with real time have been developed to achieve direct digital data transfer between the building emulator and a commercial EMCS. Based on the tests conducted, the validity of the building emulator has been established and the proportional-plus-integral control function of the EMCS assessed.link_to_subscribed_fulltex
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... 56. P. Aebischer and J. Ridet, Trends Neurosci., 2001, 24, 533. 57. EF Espejo, RJ Montoro, JA Armengol and J. Lopez-Barneo, Neuron, 1998, 20, 197. 58. MR Luquin, RJ Montoro, J. Guillen, L. Saldise, R. Insausti, J. Del Rıo and J.... more
... 56. P. Aebischer and J. Ridet, Trends Neurosci., 2001, 24, 533. 57. EF Espejo, RJ Montoro, JA Armengol and J. Lopez-Barneo, Neuron, 1998, 20, 197. 58. MR Luquin, RJ Montoro, J. Guillen, L. Saldise, R. Insausti, J. Del Rıo and J. Lopez-Barneo, Neuron, 1999, 22, 743. 59. ...
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This work investigates the physical characteristics of raindrop size distribution (DSD) in an equatorial heavy rain region based on three years of disdrometer observations carried out at Universiti Teknologi Malaysia’s (UTM’s) campus in... more
This work investigates the physical characteristics of raindrop size distribution (DSD) in an equatorial heavy rain region based on three years of disdrometer observations carried out at Universiti Teknologi Malaysia’s (UTM’s) campus in Kuala Lumpur, Malaysia. The natural characteristics of DSD are deduced, and the statistical results are found to be in accordance with the findings obtained from others disdrometer measurements. Moreover, the parameters of the Gamma distribution and the normalized Gamma model are also derived by means of method of moment (MoM) and maximum likelihood estimation (MLE). Their performances are subsequently validated using the rain rate estimation accuracy: the normalized Gamma model with the MLE-generated shape parameterµwas found to provide better accuracy in terms of long-term rainfall rate statistics, which reflects the peculiarities of the local climatology in this heavy rain region. These results not only offer a better understanding of the microphy...
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This study is aimed to investigate the relationship between ground wind direction and the seasonal variation of rain attenuation based on one year of weather station data recorded in Universiti Teknologi Malaysia (UTM), Johor, Malaysia.... more
This study is aimed to investigate the relationship between ground wind direction and the seasonal variation of rain attenuation based on one year of weather station data recorded in Universiti Teknologi Malaysia (UTM), Johor, Malaysia. Preliminary analysis of wind direction based on monsoon seasonal and their impact on rain field advection are carried out to clarify the characteristics of rain attenuation in monsoon season. It is found that rain attenuation is not only affected by the monsoon seasonal variation but it also depends on rain field advection which can be preliminary identified from the wind direction. Such information is useful for the system operators to apply appropriate site diversity techniques during heavy rain events to reduce the system outage in this particular equatorial region.
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ABSTRACT
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Caenorhabditis elegans, Mass Spectrometry, Biology, Proteomics, Medicine, and 14 moreTranslation, Western blotting, Biological Sciences, Click chemistry, Animals, CHEMICAL SCIENCES, Amino Acids, Fluorescent Antibody Technique, Amino Acid Profile, Biochemistry and molecular biology, Alanine, Proteome, Chemical Modification, and Medical and Health Sciences
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Microbiology, Biology, Medicine, Biological Sciences, Cell line, and 15 moreMice, Animals, Immunization, Lung, Enzyme, Phagocytosis, Nasal cavity, Enzyme Linked Immunosorbent Assay, Nasal Mucosa, Necrotizing Fasciitis, Group A Streptococcus, Neutralization tests, pharyngitis, Medical and Health Sciences, and Oropharynx
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Microbiology, Biology, Membrane Proteins, Molecular Microbiology, Medicine, and 15 moreBiological Sciences, High Frequency, Humans, Streptococcus Pyogenes, Hyaluronic Acid, Phagocytosis, Epithelial cells, Toxin, Streptococcus, Glycosyltransferases, Phase variation, Intracellular, Serotype, glucuronosyltransferase, and Medical and Health Sciences
Entry of serotype M1 Streptococcus pyogenes into host cells depends on binding of the host glycoprotein fibronectin (Fn) by the bacterial M1 protein. The present study was undertaken to localize the Fn binding region in M1 and assess... more
Entry of serotype M1 Streptococcus pyogenes into host cells depends on binding of the host glycoprotein fibronectin (Fn) by the bacterial M1 protein. The present study was undertaken to localize the Fn binding region in M1 and assess other potential functions of M1. A set of recombinant M1 protein fragments were assayed for their capacities to bind Fn and inhibit ingestion of streptococci by epithelial cells. M1 protein, M6 protein and internally-deleted derivatives of M1 were expressed on the surface of Lactococcus lactis. Lactococci that expressed M1 or M6 protein bound Fn and were efficiently taken up by epithelial cells. Deletion of both the N-terminal A and B repeats regions of M1 abrogated Fn binding and intracellular invasion. Deletion of either the A domain (M1DeltaA) or B repeats (M1DeltaB) significantly reduced, but did not completely eliminate, Fn binding indicating that M1 protein may possess two independent Fn binding sites. Fn binding by the M1DeltaA or M1DeltaB proteins was insufficient for efficient invasion, however, suggesting that M protein binding alters the structure of Fn that, in turn, affects the interaction between Fn and epithelial cells. Although expression of M1, M6 or M1DeltaB proteins led to aggregation of lactococcal cells, aggregation did not significantly contribute to invasion efficiency.
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Genetics, Microbiology, Immunology, Medical Microbiology, Biology, and 15 moreLocalization, Medicine, Cell line, Humans, Bacteria, Fragmentation, Microbial Pathogenesis, Potential Function, Fibronectin, Epithelial cells, Amino Acid Sequence, Lactococcus lactis, Binding Site, Intracellular, and Molecular Sequence Data
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Engineering and Geography
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This work investigates fade dynamics of satellite communication systems in equatorial heavy rain region based on a one year of Ku-band propagation measurement campaign carried out in Universiti Teknologi Malaysia (UTM), Johor, Malaysia.... more
This work investigates fade dynamics of satellite communication systems in equatorial heavy rain region based on a one year of Ku-band propagation measurement campaign carried out in Universiti Teknologi Malaysia (UTM), Johor, Malaysia. First order statistics of rain attenuation are deduced and the results are found to be in good agreement with those obtained from other beacon measurements gathered within the same area (Kuala Lumpur). Moreover, the fade duration and slope statistics of the satellite signal variations are also carefully derived and subsequently compared with the ITU-R recommendation model. Such information is useful for the system operator and radio communication engineer for the design of appropriate fade mitigation techniques as well as the quality of service that could be offered to the user (according to the time interval for a typical day). Further evaluation on the performances of several ITU-R models in the heavy rain region are needed based on the measurement...
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Abstract This contribution presents a new model for the prediction of the 1-minute integrated Complementary Cumulative Distribution Function (CCDF) of the rain rate, P (R) 1, valid for tropical and equatorial regions (specifically,... more
Abstract This contribution presents a new model for the prediction of the 1-minute integrated Complementary Cumulative Distribution Function (CCDF) of the rain rate, P (R) 1, valid for tropical and equatorial regions (specifically, latitudes ranging from 35 S to 35 N). The proposed model inherits its analytical formulation from the method currently recommended by the International Telecommunication Union Radiocommunication Sector (ITU-R) for global P (R) 1 prediction (Annex 1 of recommendation P. 837-6), but it relies on Tropical ...
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Mathematics, Environmental Science, Remote Sensing, Climate Change, Data Mining, and 12 moreAtmospheric Science, Climatology, Meteorology, Databases, Tropics, Predictive models, Accuracy, Spatial resolution, Tropical, Electrical And Electronic Engineering, Latitude, and Cumulative distribution function
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Protein misfolding and aggregation as a consequence of impaired protein homeostasis (proteostasis) not only characterizes numerous age-related diseases but also the aging process itself. Functionally related to the aging process are,... more
Protein misfolding and aggregation as a consequence of impaired protein homeostasis (proteostasis) not only characterizes numerous age-related diseases but also the aging process itself. Functionally related to the aging process are, among others, ribosomal proteins, suggesting an intimate link between proteostasis and aging. We determined by iTRAQ quantitative proteomic analysis inC. eleganshow the proteome changes with age and in response to heat shock. Levels of ribosomal proteins and mitochondrial chaperones were decreased in aged animals, supporting the notion that proteostasis is altered during aging. Mitochondrial enzymes of the tricarboxylic acid cycle and the electron transport chain were also reduced, consistent with an age-associated energy impairment. Moreover, we observed an age-associated decline in the heat shock response. In order to determine how protein synthesis is altered in aging and in response to heat shock, we complemented our global analysis by determining t...