74 research outputs found
Cysteinyl Leukotriene Levels in Esophageal Mucosal Biopsies of Children with Eosinophilic Inflammation: Are They All the Same?
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/75498/1/j.1572-0241.2006.00557.x.pd
Population Health Solutions for Assessing Cognitive Impairment in Geriatric Patients.
In December 2017, the National Academy of Neuropsychology convened an interorganizational Summit on Population Health Solutions for Assessing Cognitive Impairment in Geriatric Patients in Denver, Colorado. The Summit brought together representatives of a broad range of stakeholders invested in the care of older adults to focus on the topic of cognitive health and aging. Summit participants speciïŹcally examined questions of who should be screened for cognitive impairment and how they should be screened in medical settings. This is important in the context of an acute illness given that the presence of cognitive impairment can have signiïŹcant implications for care and for the management of concomitant diseases as well as pose a major risk factor for dementia. Participants arrived at general principles to guide future screening approaches in medical populations and identiïŹed knowledge gaps to direct future research. Key learning points of the summit included: recognizing the importance of educating patients and healthcare providers about the value of assessing current and baseline cognition;emphasizing that any screening tool must be appropriately normalized and validated in the population in which it is used to obtain accurate information, including considerations of language, cultural factors, and education; andrecognizing the great potential, with appropriate caveats, of electronic health records to augment cognitive screening and tracking of changes in cognitive health over time
Transient Increase in Cyclic AMP Localized to Macrophage Phagosomes
Cyclic AMP (cAMP) regulates many biological processes and cellular functions. The importance of spatially localized intracellular gradients of cAMP is increasingly appreciated. Previous work in macrophages has shown that cAMP is produced during phagocytosis and that elevated cAMP levels suppress host defense functions, including generation of proinflammatory mediators, phagocytosis and killing. However, the spatial and kinetic characteristics of cAMP generation in phagocytosing macrophages have yet to be examined. Using a Förster resonance energy transfer (FRET)-based cAMP biosensor, we measured the generation of cAMP in live macrophages. We detected no difference in bulk intracellular cAMP levels between resting cells and cells actively phagocytosing IgG-opsonized particles. However, analysis with the biosensor revealed a rapid decrease in FRET signal corresponding to a transient burst of cAMP production localized to the forming phagosome. cAMP levels returned to baseline after the particle was internalized. These studies indicate that localized increases in cAMP accompany phagosome formation and provide a framework for a more complete understanding of how cAMP regulates macrophage host defense functions
A Genome-Wide Association Study of Diabetic Kidney Disease in Subjects With Type 2 Diabetes
dentification of sequence variants robustly associated with predisposition to diabetic kidney disease (DKD) has the potential to provide insights into the pathophysiological mechanisms responsible. We conducted a genome-wide association study (GWAS) of DKD in type 2 diabetes (T2D) using eight complementary dichotomous and quantitative DKD phenotypes: the principal dichotomous analysis involved 5,717 T2D subjects, 3,345 with DKD. Promising association signals were evaluated in up to 26,827 subjects with T2D (12,710 with DKD). A combined T1D+T2D GWAS was performed using complementary data available for subjects with T1D, which, with replication samples, involved up to 40,340 subjects with diabetes (18,582 with DKD). Analysis of specific DKD phenotypes identified a novel signal near GABRR1 (rs9942471, P = 4.5 x 10(-8)) associated with microalbuminuria in European T2D case subjects. However, no replication of this signal was observed in Asian subjects with T2D or in the equivalent T1D analysis. There was only limited support, in this substantially enlarged analysis, for association at previously reported DKD signals, except for those at UMOD and PRKAG2, both associated with estimated glomerular filtration rate. We conclude that, despite challenges in addressing phenotypic heterogeneity, access to increased sample sizes will continue to provide more robust inference regarding risk variant discovery for DKD.Peer reviewe
Microbial Electrochemical Energy Storage and Recovery in a Combined Electrotrophic and Electrogenic Biofilm
Here we report enrichment from a marine-derived inoculum of a nonphotosynthetic electroactive biofilm that is capable of both consuming electricity (electrotrophy) and producing electricity (electrogenesis) from a single electrode. With the alternation of the electrode potential between â0.4 and 0.0 VSHE every 10 min, alternating anodic and cathodic currents increased in lock step (maximum current density of ±1.4 ± 0.4 A/m2 in both modes, Coulombic efficiency of âŒ98% per chargeâdischarge cycle), which is consistent with alternating between generation and consumption of energy storage compounds by the biofilm. Cyclic voltammetry exhibited a single sigmoid-shaped feature spanning anodic and cathodic limiting currents centered at â0.15 VSHE, a phenomenon not observed to date for an electroactive biofilm, and square wave voltammetry exhibited reversible peaks at â0.15 and â0.05 VSHE, suggesting the same redox cofactor(s) facilitates electron transport at the biofilmâelectrode interface in both modes. Hydrogen and carbon monoxide, known energy and/or carbon sources for cellular metabolism, but no volatile fatty acids, were detected in reactors. Cells and cell clusters were spread across the electrode surface, as seen by confocal microscopy. These results suggest that a single microbial electrochemical biofilm can alternate between storing energy and generating power, furthering the potential applicability of bioelectrochemical systems
Optofluidic characterization of marine algae using a microflow cytometer
The effects of global warming, pollution in river effluents, and changing ocean currents can be studied by characterizing variations in phytoplankton populations. We demonstrate the design and fabrication of a Microflow Cytometer for characterization of phytoplankton. Guided by chevron-shaped grooves on the top and bottom of a microfluidic channel, two symmetric sheath streams wrap around a central sample stream and hydrodynamically focus it in the center of the channel. The lasers are carefully chosen to provide excitation light close to the maximum absorbance wavelengths for the intrinsic fluorophores chlorophyll and phycoerythrin, and the excitation light is coupled to the flow cytometer through the use of an optical fiber. Fluorescence and light scatter are collected using two multimode optical fibers placed at 90-degree angles with respect to the excitation fiber. Light emerging from these collection fibers is directed through optical bandpass filters into photomultiplier tubes. The cytometer measured the optical and side scatter properties of Karenia b., Synechococcus sp., Pseudo-Nitzchia, and Alexandrium. The effect of the sheath-to-sample flow-rate ratio on the light scatter and fluorescence of these marine microorganisms was investigated. Reducing the sample flow rate from 200 ÎŒL/min to 10 ÎŒL/min produced a more tightly focused sample stream and less heterogeneous signals
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