1,143 research outputs found
Diabetes-induced alterations in urothelium function:Enhanced ATP release and nerve-evoked contractions in the streptozotocin rat bladder
Up to 80% of patients with diabetes mellitus develop lower urinary tract complications, most commonly diabetic bladder dysfunction (DBD). The aim of this study was to investigate the impact of diabetes on the function of the inner bladder lining (urothelium). Bladder compliance and intraluminal release of urothelial mediators, adenosine triphosphate (ATP) and acetylcholine (ACh) in response to distension were investigated in whole bladders isolated from 2‐ and 12‐week streptozotocin (STZ)‐diabetic rats. Intact and urothelium‐denuded bladder strips were used to assess the influence of the urothelium on bladder contractility. Intraluminal ATP release was significantly enhanced at 2 weeks of diabetes, although not at 12 weeks. In contrast, intraluminal ACh release was unaltered by diabetes. Bladder compliance was also significantly enhanced at both 2 and 12 weeks of diabetes, with greatly reduced intravesical pressures in response to distension. Nerve‐evoked contractions of bladder strips were significantly greater at 2 weeks of diabetes. When the urothelium was absent, nerve‐evoked contractions were reduced, but contractions remained significantly elevated at lower frequencies of stimulation (<5 Hz) in diabetics. Interestingly, although relaxations of bladder strips to isoprenaline were unaltered by diabetes, removal of the urothelium unmasked significantly enhanced relaxations in strips from 2‐ and 12‐week diabetic animals. In conclusion, diabetes alters urothelial function. Enhanced urothelial ATP release may be involved in the hypercontractility observed at early time points of diabetes. These alterations are time‐dependent and may contribute to the mechanisms at play during the development of diabetic bladder dysfunction.Full Tex
Phenotypic landscape inference reveals multiple evolutionary paths to C photosynthesis
C photosynthesis has independently evolved from the ancestral C
pathway in at least 60 plant lineages, but, as with other complex traits, how
it evolved is unclear. Here we show that the polyphyletic appearance of C
photosynthesis is associated with diverse and flexible evolutionary paths that
group into four major trajectories. We conducted a meta-analysis of 18 lineages
containing species that use C, C, or intermediate C-C forms of
photosynthesis to parameterise a 16-dimensional phenotypic landscape. We then
developed and experimentally verified a novel Bayesian approach based on a
hidden Markov model that predicts how the C phenotype evolved. The
alternative evolutionary histories underlying the appearance of C
photosynthesis were determined by ancestral lineage and initial phenotypic
alterations unrelated to photosynthesis. We conclude that the order of C
trait acquisition is flexible and driven by non-photosynthetic drivers. This
flexibility will have facilitated the convergent evolution of this complex
trait
Postpartum Depression: Development of a Screening Protocol in the Neonatal Intensive Care Unit
Postpartum depression (PPD) affects approximately 19% of all postpartum women. Evidence indicates an increased risk for mothers of hospitalized infants, with estimates ranging from 28% to 67%. The American Academy of Pediatrics and Bright Futures recommend mothers be screened for postpartum depression at the infants’ well-child appointments. During hospitalizations, there are no well-child appointments; thus, no postpartum depression screening. This project aims to 1) improve knowledge of PPD in the staff of the Neonatal Intensive Care Unit (NICU) and 2) investigate the staff’s interest level in implementing a PPD screening protocol. Utilizing the Plan-Do-Study-Act (PDSA) framework, a protocol was developed to screen postpartum mothers at 1-, 2-, 4-, and 6-month intervals. Staff of the NICU received a 30-minute educational presentation on PPD, the developed PPD screening protocol, and available resources for mothers who screen positive for PPD. The effectiveness of the education was measured using pre-and post-education Likert-style surveys. Outcomes, as measured by a self-reported Likert survey, indicated a ~74% increase in PPD knowledge and a ~64% increase in willingness to screen for PPD in the NICU. This project suggests that educating NICU staff increases knowledge and willingness to screen for PPD in the NICU. This quality improvement project adds to the growing body of literature that inpatient PPD screening is feasible and necessary
Redundant SCARECROW genes pattern distinct cell layers in roots and leaves of maize
The highly efficient C4 photosynthetic pathway is facilitated by ‘Kranz’ leaf anatomy. In Kranz leaves, closely spaced veins are encircled by concentric layers of photosynthetic bundle sheath (inner) and mesophyll (outer) cells. Here, we demonstrate that, in the C4 monocot maize, Kranz patterning is regulated by redundant function of SCARECROW 1 (ZmSCR1) and a previously uncharacterized homeologue: ZmSCR1h. ZmSCR1 and ZmSCR1h transcripts accumulate in ground meristem cells of developing leaf primordia and in Zmscr1;Zmscr1h mutant leaves, most veins are separated by one rather than two mesophyll cells; many veins have sclerenchyma above and/or below instead of mesophyll cells; and supernumerary bundle sheath cells develop. The mutant defects are unified by compromised mesophyll cell development. In addition to Kranz defects, Zmscr1;Zmscr1h mutants fail to form an organized endodermal layer in the root. Collectively, these data indicate that ZmSCR1 and ZmSCR1h redundantly regulate cell-type patterning in both the leaves and roots of maize. Leaf and root pathways are distinguished, however, by the cell layer in which they operate – mesophyll at a two-cell distance from leaf veins versus endodermis immediately adjacent to root vasculature
Finding the genes to build C4 rice
Rice, a C3 crop, is a staple food for more than half of the world's population, with most consumers living in developing countries. Engineering C4 photosynthetic traits into rice is increasingly suggested as a way to meet the 50% yield increase that is predicted to be needed by 2050. Advances in genome-wide deep-sequencing, gene discovery and genome editing platforms have brought the possibility of engineering a C3 to C4 conversion closer than ever before. Because C4 plants have evolved independently multiple times from C3 origins, it is probably that key genes and gene regulatory networks that regulate C4 were recruited from C3 ancestors. In the past five years there have been over 20 comparative transcriptomic studies published that aimed to identify these recruited C4 genes and regulatory mechanisms. Here we present an overview of what we have learned so far and preview the efforts still needed to provide a practical blueprint for building C4 rice
Detector Description and Performance for the First Coincidence Observations between LIGO and GEO
For 17 days in August and September 2002, the LIGO and GEO interferometer
gravitational wave detectors were operated in coincidence to produce their
first data for scientific analysis. Although the detectors were still far from
their design sensitivity levels, the data can be used to place better upper
limits on the flux of gravitational waves incident on the earth than previous
direct measurements. This paper describes the instruments and the data in some
detail, as a companion to analysis papers based on the first data.Comment: 41 pages, 9 figures 17 Sept 03: author list amended, minor editorial
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Search for Gravitational Waves from Primordial Black Hole Binary Coalescences in the Galactic Halo
We use data from the second science run of the LIGO gravitational-wave
detectors to search for the gravitational waves from primordial black hole
(PBH) binary coalescence with component masses in the range 0.2--.
The analysis requires a signal to be found in the data from both LIGO
observatories, according to a set of coincidence criteria. No inspiral signals
were found. Assuming a spherical halo with core radius 5 kpc extending to 50
kpc containing non-spinning black holes with masses in the range 0.2--, we place an observational upper limit on the rate of PBH coalescence
of 63 per year per Milky Way halo (MWH) with 90% confidence.Comment: 7 pages, 4 figures, to be submitted to Phys. Rev.
Analysis of LIGO data for gravitational waves from binary neutron stars
We report on a search for gravitational waves from coalescing compact binary
systems in the Milky Way and the Magellanic Clouds. The analysis uses data
taken by two of the three LIGO interferometers during the first LIGO science
run and illustrates a method of setting upper limits on inspiral event rates
using interferometer data. The analysis pipeline is described with particular
attention to data selection and coincidence between the two interferometers. We
establish an observational upper limit of 1.7 \times 10^{2}M_\odot$.Comment: 17 pages, 9 figure
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