Publications by authors named "Stephen So"

Homologous recombination repairs DNA breaks and sequence gaps via the production of joint DNA intermediates such as Holliday junctions. Dissolving Holliday junctions into linear DNA repair products requires the activity of the Sgs1 helicase in yeast and of its homologs in other organisms. Recent studies suggest that the functions of these conserved helicases are regulated by sumoylation; however, the mechanisms that promote their sumoylation are not well understood.

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Use of machine learning to accurately detect aspirating swallowing sounds in children is an evolving field. Previously reported classifiers for the detection of aspirating swallowing sounds in children have reported sensitivities between 79 and 89%. This study aimed to investigate the accuracy of using an automatic speaker recognition approach to differentiate between normal and aspirating swallowing sounds recorded from digital cervical auscultation in children.

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SUMO modification regulates diverse cellular processes by targeting hundreds of proteins. However, the limited number of sumoylation enzymes raises the question of how such a large number of substrates are efficiently modified. Specifically, how genome maintenance factors are dynamically sumoylated at DNA replication and repair sites to modulate their functions is poorly understood.

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Conformational equilibria in the protein denatured state have key roles regulating folding, stability, and function. The extent of conformational bias in the protein denatured state under folding conditions, however, has thus far proven elusive to quantify, particularly with regard to its sequence dependence and energetic character. To better understand the structural preferences of the denatured state, we analyzed both the sequence dependence to the mean hydrodynamic size of disordered proteins in water and the impact of heat on the coil dimensions, showing that the sequence dependence and thermodynamic energies associated with intrinsic biases for the α and polyproline II (PPII) backbone conformations can be obtained.

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Background And Objectives: Heart rate variability (HRV) has increasingly been linked to medical phenomena and several HRV metrics have been found to be good indicators of patient health. This has enabled generalised treatment plans to be developed in order to respond to subtle personal differences that are reflected in HRV metrics. There are several established HRV analysis platforms and methods available within the literature; some of which provide command line operation across databases but do not offer extensive graphical user interface (GUI) and editing functionality, while others offer extensive ECG editing but are not feasible over large datasets without considerable manual effort.

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Background: The cardioprotective effects of Persea americana extract was investigated on biochemical activities of high salt-fed adult Wistar rats in this study.

Method: Forty healthy Wistar rats of both sexes weighing 120 to 150 g were randomly assigned into 8 groups of 5 rats each (groups A, B, C, D, E, F, G, and H). Rats in groups A, F, G, and H were fed with standard laboratory pellets, while groups B, C, D, and E were fed on the high-salt diet for 4 weeks.

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A ppb-level formaldehyde (H2CO) sensor was developed using a thermoelectrically cooled (TEC), continuous-wave (CW) room temperature interband cascade laser (ICL) emitting at 3.59 μm and a miniature dense pattern multipass gas cell with >50 m optical path length. Performance of the sensor was investigated with two measurement schemes: direct absorption (DAS) and wavelength modulation spectroscopy (WMS).

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Galectin-1 (Gal-1), an endogenous β-galactoside-binding protein, binds to laminins, which are highly expressed in the nucleus pulposus (NP) of the intervertebral disc (IVD). The objective of this study is to evaluate the expression of Gal-1 protein in IVD tissues during aging and the effect of Gal-1 on IVD cell adhesion to laminins. Tissues from rat, porcine, and human (scoliosis or disc degeneration) IVDs were used to evaluate Gal-1 expression via immunostaining, RT-PCR, and Western blot analysis.

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Instruction is critical in order to ensure correct technique with pressurized metered-dose inhalers (pMDIs) by patients. The aim of this study was to compare the effects over time of two educational interventions delivered in community pharmacy to pMDI users. In this randomized controlled parallel-group study, pMDI technique was assessed before and after written and verbal instruction, alone or with physical demonstration, at baseline and 4, 8, and 16 weeks.

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Objective: Prior reports document macrophage and lymphocyte infiltration with proinflammatory cytokine expression in pathologic intervertebral disc (IVD) tissues. Nevertheless, the role of the Th17 lymphocyte lineage in mediating disc disease remains uninvestigated. We undertook this study to evaluate the immunophenotype of pathologic IVD specimens, including interleukin-17 (IL-17) expression, from surgically obtained IVD tissue and from nondegenerated autopsy control tissue.

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Study Design: The authors investigated gait abnormalities and mechanical hypersensitivity associated with invertebral disc herniation in a rat model of radiculopathy. Further evaluation involved assessing how nucleus pulposus (NP) injury affected systemic cytokine expression and molecular changes at the dorsal root ganglion (DRG).

Objective: The objective of this work was to describe the gait and behavioral changes in an animal model of disc-herniation induced radiculopathy.

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The goal of this study was to evaluate the potential suitability of collagen Vitrigel (CV) membrane as a substrate for the separate reconstruction of the three main cellular layers of the cornea. Limbal explants, keratocytes, and endothelial cells were cultured on transparent membranes made of type I collagen. The resulting cell sheets were evaluated using RT-PCR, in addition to light and electron microscopy.

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The development of an interband cascade laser (ICL) based spectroscopic trace-gas sensor for the simultaneous detection of two atmospheric trace gases is reported. The sensor performance was evaluated using two ICLs capable of targeting formaldehyde (H2CO) and ethane (C2H6). Minimum detection limits of 3.

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A laser spectrometer based on difference frequency generation (DFG) was deployed for real-time long-term monitoring of HCHO concentrations at an environmental monitoring site located at Deer Park, Texas, in the Greater Houston area. Three HCHO concentration measurements were made during the periods of July 20-31 (period I), August 2-14 (period II), and August 24-September 25 (period III), 2002. In periods I and II, differences in HCHO concentrations are apparent between day and night measurements, with elevated concentrations during daylight hours.

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Simultaneous exhaled carbonyl sulfide (OCS) and carbon dioxide concentration measurements in human breath are demonstrated with a compact pulsed quantum-cascade laser-based gas sensor. We achieved a noise-equivalent sensitivity (1sigma) of 1.2 parts per billion by measuring a well-isolated OCS P(11) absorption line in the v3 band at 2057.

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