559 research outputs found
Exposure of human renal proximal tubular cells to glucose leads to accumulation of type IV collagen and fibronectin by decreased degradation
Exposure of human renal proximal tubular cells to glucose leads to accumutation of type IV collagen and fibronectin by decreased degradation. Thickening and reduplication of the tubular basement membrane has been reported as an early event in diabetic nephropathy. In the current study we examined the effects of elevated D-glucose concentrations on human proximal tubular (HPTC) type IV collagen and fibronectin turnover. Incubation of confluent growth arrested HPTC with 25mM D-glucose led to accumulation of both type IV collagen and fibronectin. This effect was maximal at 48 hours and represented a sevenfold increase for fibronectin (N = 4, P = 0.04), and a threefold increase for type IV collagen (N = 3, P = 0.03) over cells exposed to 5mM D-glucose controls. This increase was not dependent on new gene transcription for either protein. Tissue inhibitor of metalloproteinases (TIMP 1 + TIMP 2) were induced following addition of 25mM D-glucose, but not when cells were exposed to 5mM D-glucose. Twenty-four hours after the addition of 25mM D-glucose there was an eightfold increase in TIMP 1 (P = 0.009, N = 4), and a tenfold increase in TIMP 2 levels (P = 0.003, N = 4), over the control values for both inhibitors. The increase in both TIMP 1 and TIMP 2 in response to 25mM D-glucose was abrogated in a dose dependent manner by the aldose reductase inhibitor sorbinil. Gelatin-substrate gel zymography showed increased activity of gelatinase A, but not of gelatinase B in response to the addition of 25mM D-glucose to HPTC. The induction of gelatinase A was accompanied by increased gelatinase A mRNA expression, which was inhibited both by protein kinase C (PKC) depletion using PMA pre-treatment, and by the addition of a PKC inhibitor. These data demonstrate that the glucose-induced accumulation of type IV collagen and fibronectin is unrelated to increased gene transcription, but may involve alterations in the degradative pathway of these basement membrane constituents. Furthermore, the data demonstrate that glucose may simultaneously activate two intracellular pathways (the polyol pathway and a PKC dependent activation pathway), which are involved in mediating separate, complementary effects on cell function
Southern Cosmology Survey III: QSO's from Combined GALEX and Optical Photometry
We present catalogs of QSO candidates selected using photometry from GALEX
combined with SDSS in the Stripe 82 region and Blanco Cosmology Survey (BCS)
near declination -55 degrees. The SDSS region contains ~700 objects with
magnitude i < 20 and ~3600 objects with i < 21.5 in a ~60 square degree sky
region, while the BCS region contains ~280 objects with magnitude i < 20 and
~2000 objects with i < 21.5 for a 11 square degree sky region that is being
observed by three current microwave Sunyaev-Zeldovich surveys. Our QSO catalog
is the first one in the BCS region. Deep GALEX exposures (~2000 seconds in FUV
and NUV, except in three fields) provide high signal-to-noise photometry in the
GALEX bands (FUV, NUV < 24.5 mag). From this data, we select QSO candidates
using only GALEX and optical r-band photometry, using the method given by Atlee
and Gould (2008). In the Stripe 82 field, 60% (30%) of the GALEX selected QSO's
with optical magnitude i<20 (i<21.5) also appear in the Richards et al. (2008)
QSO catalog constructed using 5-band optical SDSS photometry. Comparison with
the same catalog by Richards et al. shows that the completeness of the sample
is approximately 40%(25%). However, for regions of the sky with very low dust
extinction, like the BCS 23hr field and the Stripe 82 between 0 and 10 degrees
in RA, our completeness is close to 95%, demonstrating that deep GALEX
observations are almost as efficient as multi-wavelength observations at
finding QSO's. GALEX observations thus provide a viable alternate route to QSO
catalogs in sky regions where u-band optical photometry is not available. The
full catalog is available at http://www.ice.csic.es/personal/jimenez/PHOTOZComment: Submitted to ApJ
Improving Photometric Redshifts using GALEX Observations for the SDSS Stripe 82 and the Next Generation of SZ Cluster Surveys
Four large-area Sunyaev-Zeldovich (SZ) experiments -- APEX-SZ, SPT, ACT, and
Planck -- promise to detect clusters of galaxies through the distortion of
Cosmic Microwave Background photons by hot (> 10^6 K) cluster gas (the SZ
effect) over thousands of square degrees. A large observational follow-up
effort to obtain redshifts for these SZ-detected clusters is under way. Given
the large area covered by these surveys, most of the redshifts will be obtained
via the photometric redshift (photo-z) technique. Here we demonstrate, in an
application using ~3000 SDSS stripe 82 galaxies with r<20, how the addition of
GALEX photometry (FUV, NUV) greatly improves the photometric redshifts of
galaxies obtained with optical griz or ugriz photometry. In the case where
large spectroscopic training sets are available, empirical neural-network-based
techniques (e.g., ANNz) can yield a photo-z scatter of . If large spectroscopic training sets are not available, the addition of
GALEX data makes possible the use simple maximum likelihood techniques, without
resorting to Bayesian priors, and obtains , accuracy that
approaches the accuracy obtained using spectroscopic training of neural
networks on ugriz observations. This improvement is especially notable for blue
galaxies. To achieve these results, we have developed a new set of high
resolution spectral templates based on physical information about the star
formation history of galaxies. We envision these templates to be useful for the
next generation of photo-z applications. We make our spectral templates and new
photo-z catalogs available to the community at
http://www.ice.csic.es/personal/jimenez/PHOTOZ .Comment: 10 pages, 8 figure
Health Care Consumers: Choices and Constraints
This article summarizes the research and data currently available on different dimensions of consumer choice. These dimensions include not only whether to participate in a health care plan and which plan to select if given a choice but also the decisions that lead to having a choice and the implications of making the choice. Data are presented on what choices consumers face, how many are given what kinds of choices, what constraints they face, what we know about how they make these choices, and what information they are given and what they use. The majority of Americans are offered some kind of health insurance plan either through their place of employment or as a dependent on someone else’s employer-sponsored health plan. About half of those offered health insurance are offered a choice, usually of only two or three plans. The majority elect to participate in one of those plans.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/68465/2/10.1177_107755879905600102.pd
Perception of differentiation cues by GATA factors in primitive endoderm lineage determination of mouse embryonic stem cells
AbstractThe formation of the primitive endoderm covering the inner cell mass of early mouse embryos can be simulated in vitro by the differentiation of mouse embryonic stem (ES) cells in culture following either aggregation of suspended cells or stimulation of cell monolayers with retinoic acid. The developmentally regulated transcription factors GATA-4 and GATA-6 have determining role in mouse extraembryonic endoderm development. We analyzed the in vitro differentiation of mouse embryonic stem cells deficient of GATA factors and conclude that GATA-4 is required for ES cells to perceive a cell positioning (cell aggregation) signal and GATA-6 is required to sense morphogenic (retinoic acid) signal. The collaboration between GATA-6 and GATA-4, or GATA-6 and GATA-5 which can substitute for GATA-4, is involved in the perception of differentiation cues by embryonic stem cells in their determination of endoderm lineage. This study indicates that the lineage differentiation of ES cells can be manipulated by the expression of GATA factors
Deep GALEX Imaging of the HST/COSMOS Field: A First Look at the Morphology of z~0.7 Star-forming Galaxies
We present a study of the morphological nature of redshift z~0.7 star-forming
galaxies using a combination of HST/ACS, GALEX and ground-based images of the
COSMOS field. Our sample consists of 8,146 galaxies, 5,777 of which are
detected in the GALEX near-ultraviolet band down to a limiting magnitude of
25.5 (AB). We make use of the UV to estimate star formation rates, correcting
for the effect of dust using the UV-slope, and compute, from the ACS F814W
images, the C,A,S,G,M20 morphological parameters for all objects in our sample.
We observe a morphological bimodality in the galaxy population and show that it
has a strong correspondence with the FUV - g color bimodality. We conclude that
UV-optical color predominantly evolves concurrently with morphology. We observe
many of the most star-forming galaxies to have morphologies approaching that of
early-type galaxies, and interpret this as evidence that strong starburst
events are linked to bulge growth and constitute a process through which
galaxies can be brought from the blue to the red sequence while simultaneously
modifying their morphology accordingly. We conclude that the red sequence has
continued growing at z~<0.7. We also observe z~0.7 galaxies to have physical
properties similar to that of local galaxies, except for higher star formation
rates. Whence we infer that the dimming of star-forming galaxies is responsible
for most of the evolution in the star formation rate density of the Universe
since that redshift, although our data are also consistent with a mild number
evolution. [abridged]Comment: 29 pages including 22 figures. Accepted for publication in ApJS
COSMOS Special Issue. A copy of the paper with high resolution figures is
available at http://www.astro.columbia.edu/~michel/galex_cosmos_paper.pd
Barriers to leisure participation for people with dementia and their carers: An exploratory analysis of carer and people with dementia's experiences.
Leisure has emerged as a prominent research theme within the growing body of knowledge on dementia, with a focus on physical activity. Yet participation in any form of leisure presupposes an ability to freely choose to partake in activities and to negotiate one's way around key barriers. In the case of dementia, the ability to undertake leisure activities is subject to a greater range of barriers, structured in a hierarchical manner that contributes to social exclusion if not addressed. This study based on focus groups with people with dementia and their family members conducted in Dorset, UK illustrates a range of barriers to leisure participation. How to create or maintain leisure opportunities for those living with dementia where households affected by dementia do not adopt avoidance behaviour, compounding a sense of isolation and exclusion is a challenge. Leisure can be an important strategy framed as a form of resistance to the social disabilities experienced by those living with dementia and it is potentially isolating impact
Crossing the Dripline to 11N Using Elastic Resonance Scattering
The level structure of the unbound nucleus 11N has been studied by 10C+p
elastic resonance scattering in inverse geometry with the LISE3 spectrometer at
GANIL, using a 10C beam with an energy of 9.0 MeV/u. An additional measurement
was done at the A1200 spectrometer at MSU. The excitation function above the
10C+p threshold has been determined up to 5 MeV. A potential-model analysis
revealed three resonance states at energies 1.27 (+0.18-0.05) MeV (Gamma=1.44
+-0.2 MeV), 2.01(+0.15-0.05) MeV, (Gamma=0.84 +-$0.2 MeV) and 3.75(+-0.05) MeV,
(Gamma=0.60 +-0.05 MeV) with the spin-parity assignments I(pi) =1/2+, 1/2- and
5/2+, respectively. Hence, 11N is shown to have a ground state parity inversion
completely analogous to its mirror partner, 11Be. A narrow resonance in the
excitation function at 4.33 (+-0.05) MeV was also observed and assigned
spin-parity 3/2-.Comment: 14 pages, 9 figures, twocolumn Accepted for publication in PR
Revision and Update of the Consensus Definitions of Invasive Fungal Disease From the European Organization for Research and Treatment of Cancer and the Mycoses Study Group Education and Research Consortium.
BACKGROUND: Invasive fungal diseases (IFDs) remain important causes of morbidity and mortality. The consensus definitions of the Infectious Diseases Group of the European Organization for Research and Treatment of Cancer and the Mycoses Study Group have been of immense value to researchers who conduct clinical trials of antifungals, assess diagnostic tests, and undertake epidemiologic studies. However, their utility has not extended beyond patients with cancer or recipients of stem cell or solid organ transplants. With newer diagnostic techniques available, it was clear that an update of these definitions was essential. METHODS: To achieve this, 10 working groups looked closely at imaging, laboratory diagnosis, and special populations at risk of IFD. A final version of the manuscript was agreed upon after the groups' findings were presented at a scientific symposium and after a 3-month period for public comment. There were several rounds of discussion before a final version of the manuscript was approved. RESULTS: There is no change in the classifications of "proven," "probable," and "possible" IFD, although the definition of "probable" has been expanded and the scope of the category "possible" has been diminished. The category of proven IFD can apply to any patient, regardless of whether the patient is immunocompromised. The probable and possible categories are proposed for immunocompromised patients only, except for endemic mycoses. CONCLUSIONS: These updated definitions of IFDs should prove applicable in clinical, diagnostic, and epidemiologic research of a broader range of patients at high-risk
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