64 research outputs found
Urotensin II and the Circulatory System
Urotensin II (UII), first isolated from the spinal cord of teleost fish, is the most potent vasoconstrictor known. It is more potent than endothelin-1 and acts through UT-II, a seven-transmembrane-domain, G-protein-coupled receptor. Human UII is an 11-amino-acid cyclic peptide that is expressed in various tissues, including the central nervous system, heart, kidney, and blood vessels. It circulates in human plasma, and its plasma level is elevated in renal failure, congestive heart failure, diabetes, and portal hypertension. In the kidney, UII has vasodilatory and natriuretic effects, mediated through nitric oxide. The development of UII-receptor antagonists may provide a useful research tool, and a novel treatment for cardiorenal diseases
Collisional effects on the drift-cyclotron instability
The drift-cyclotron instability in a weakly collisional plasma is considered including temperature perturbations. Collisions are described by a model Fokker-Planck equations. The growth rate of the instability is obtained analytically.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/21759/1/0000153.pd
Symbolic Backwards-Reachability Analysis for Higher-Order Pushdown Systems
Higher-order pushdown systems (PDSs) generalise pushdown systems through the
use of higher-order stacks, that is, a nested "stack of stacks" structure.
These systems may be used to model higher-order programs and are closely
related to the Caucal hierarchy of infinite graphs and safe higher-order
recursion schemes.
We consider the backwards-reachability problem over higher-order Alternating
PDSs (APDSs), a generalisation of higher-order PDSs. This builds on and extends
previous work on pushdown systems and context-free higher-order processes in a
non-trivial manner. In particular, we show that the set of configurations from
which a regular set of higher-order APDS configurations is reachable is regular
and computable in n-EXPTIME. In fact, the problem is n-EXPTIME-complete.
We show that this work has several applications in the verification of
higher-order PDSs, such as linear-time model-checking, alternation-free
mu-calculus model-checking and the computation of winning regions of
reachability games
Prognostic Value of N-terminal B-type Natriuretic Peptide in Patients with Acute Myocardial Infarction: A Multicenter Study
Background: Several models have been developed to help the clinician in risk stratification for Acute Coronary Syndrome (ACS),such as the TIMI and GRACE risk scores. However, there is conflicting evidence for the prognostic value of NT-ProBNP in acute myocardial infarction (AMI).
Objective: (1) To explore the association of NT-proBNP with 30-day clinical outcome in AMI patients. (2) To compare the prognostic value of NT-proBNP with TIMI and GRACE risk scores in AMI patients.
Methods: We conducted a multicenter, prospective observational study recruiting patients presented with AMI between 29-October-2015 and 14-January-2017, involving 1 cardiology referral centre and 4 non-cardiology hospitals. NT-proBNP level (Alere Triage®, US)was measured within 24 hours fromthe diagnosis of AMI. Patientswere followed-up for 1 month.
Results: A total of 186 patients were recruited, 143 from tertiary cardiology centre and 43 from non-cardiology hospitals. Mean age was 54.7±10.0 years, 87.6% male and 64% were STEMI. The NT-proBNP level ranged from 60 to 16700pg/ml, with a median of 714pg/ml. Using the 75th centile as the cutoff, Kaplan-Meier survival analysis for the 30-day cardiac related mortality was significantly higher for patient with NT-proBNP level of ≥1600pg/ml (6.4% vs. 0.7%, p=0.02). Cox-regression analysis showed that NT-proBNP level of ≥1600pg/ml was an independent
predictor of 30-day cardiac related mortality, regardless of TIMI risk score, GRACE score, LV ejection fraction and study hospitals (HR 9.274, p=0.054, 95%CI 0.965, 89.161). Readmission for heart failure at 30-day was also higher for patient with NT-proBNP level of ≥1600pg/ml (HR 9.308, p=0.053, 95%CI 0.969, 89.492). NT-proBNP level was not
associated with all-cause mortality, risk of readmission for ACS, arrhythmia and stroke (pN0.05). By adding 50 score to GRACE risk score for NT-proBNP level of ≥1600pg/ml, combination of GraceNT-proBNP scores of more than 200 appeared to be a better independent predictor for 30-day cardiac related mortality (HR:28.28, p=0.004, 95%CI 2.94, 272.1). ROC analysis showed that this new score had 75% sensitivity and 91.2% specificity in predicting 30-day cardiac related mortality (AUC
0.791, p=0.046).
Conclusions: NT-proBNP is a useful point-of-care risk stratification biomarker in AMI. It can be combined to the current risk score model for better risk stratification in AMI patients
Particle-Vortex Duality and the Modular Group: Applications to the Quantum Hall Effect and Other 2-D Systems
We show how particle-vortex duality implies the existence of a large
non-abelian discrete symmetry group which relates the electromagnetic response
for dual two-dimensional systems in a magnetic field. For conductors with
charge carriers satisfying Fermi statistics (or those related to fermions by
the action of the group), the resulting group is known to imply many, if not
all, of the remarkable features of Quantum Hall systems. For conductors with
boson charge carriers (modulo group transformations) a different group is
predicted, implying equally striking implications for the conductivities of
these systems, including a super-universality of the critical exponents for
conductor/insulator and superconductor/insulator transitions in two dimensions
and a hierarchical structure, analogous to that of the quantum Hall effect but
different in its details. Our derivation shows how this symmetry emerges at low
energies, depending only weakly on the details of dynamics of the underlying
systems.Comment: 22 pages, LaTeX, 2 figures, uses revte
Global, regional, and national age-sex-specific mortality and life expectancy, 1950–2017: a systematic analysis for the Global Burden of Disease Study 2017
BACKGROUND:
Assessments of age-specific mortality and life expectancy have been done by the UN Population Division, Department of Economics and Social Affairs (UNPOP), the United States Census Bureau, WHO, and as part of previous iterations of the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD). Previous iterations of the GBD used population estimates from UNPOP, which were not derived in a way that was internally consistent with the estimates of the numbers of deaths in the GBD. The present iteration of the GBD, GBD 2017, improves on previous assessments and provides timely estimates of the mortality experience of populations globally.
METHODS:
The GBD uses all available data to produce estimates of mortality rates between 1950 and 2017 for 23 age groups, both sexes, and 918 locations, including 195 countries and territories and subnational locations for 16 countries. Data used include vital registration systems, sample registration systems, household surveys (complete birth histories, summary birth histories, sibling histories), censuses (summary birth histories, household deaths), and Demographic Surveillance Sites. In total, this analysis used 8259 data sources. Estimates of the probability of death between birth and the age of 5 years and between ages 15 and 60 years are generated and then input into a model life table system to produce complete life tables for all locations and years. Fatal discontinuities and mortality due to HIV/AIDS are analysed separately and then incorporated into the estimation. We analyse the relationship between age-specific mortality and development status using the Socio-demographic Index, a composite measure based on fertility under the age of 25 years, education, and income. There are four main methodological improvements in GBD 2017 compared with GBD 2016: 622 additional data sources have been incorporated; new estimates of population, generated by the GBD study, are used; statistical methods used in different components of the analysis have been further standardised and improved; and the analysis has been extended backwards in time by two decades to start in 1950.
FINDINGS:
Globally, 18·7% (95% uncertainty interval 18·4–19·0) of deaths were registered in 1950 and that proportion has been steadily increasing since, with 58·8% (58·2–59·3) of all deaths being registered in 2015. At the global level, between 1950 and 2017, life expectancy increased from 48·1 years (46·5–49·6) to 70·5 years (70·1–70·8) for men and from 52·9 years (51·7–54·0) to 75·6 years (75·3–75·9) for women. Despite this overall progress, there remains substantial variation in life expectancy at birth in 2017, which ranges from 49·1 years (46·5–51·7) for men in the Central African Republic to 87·6 years (86·9–88·1) among women in Singapore. The greatest progress across age groups was for children younger than 5 years; under-5 mortality dropped from 216·0 deaths (196·3–238·1) per 1000 livebirths in 1950 to 38·9 deaths (35·6–42·83) per 1000 livebirths in 2017, with huge reductions across countries. Nevertheless, there were still 5·4 million (5·2–5·6) deaths among children younger than 5 years in the world in 2017. Progress has been less pronounced and more variable for adults, especially for adult males, who had stagnant or increasing mortality rates in several countries. The gap between male and female life expectancy between 1950 and 2017, while relatively stable at the global level, shows distinctive patterns across super-regions and has consistently been the largest in central Europe, eastern Europe, and central Asia, and smallest in south Asia. Performance was also variable across countries and time in observed mortality rates compared with those expected on the basis of development.
INTERPRETATION:
This analysis of age-sex-specific mortality shows that there are remarkably complex patterns in population mortality across countries. The findings of this study highlight global successes, such as the large decline in under-5 mortality, which reflects significant local, national, and global commitment and investment over several decades. However, they also bring attention to mortality patterns that are a cause for concern, particularly among adult men and, to a lesser extent, women, whose mortality rates have stagnated in many countries over the time period of this study, and in some cases are increasing
Evaluation of surfactant assisted pressurized liquid extraction for the determination of glycyrrhizin and ephedrine in medicinal plants
10.1016/j.aca.2006.09.019Analytica Chimica Acta5832289-29
A wearable navigation system for visually impaired users
i-CREATe 2012 - 6th International Convention on Rehabilitation Engineering and Assistive Technology
The effects of betamethasone dipropionate and fish oil on HaCaT proliferation and apoptosis
The current work examined the effect of fish oil (FO) and betamethasone dipropionate (BD) on the growth of immortalized HaCaT keratinocytes. HaCaT cells were grown and treated with FO and/or BD, and proliferation determined using the MTT method. The cells were further probed by immunocytochemistry (ICC) techniques for apoptosis using Cleaved Caspase-3 Asp175, and inflammatory processes using cyclooxygenase-2 (COX-2). The addition of FO increased the inhibition of HaCaT cells by 27.2%, from 43.15% to 70.35% compared to BD alone (p 0.034). FO alone appeared to induce expression of Asp175 and the effect was greater in combination with BD. The net effect, however, were less than BD alone. Similar observations were seen with regards to COX-2 inhibition. The added benefits of FO to the effect of BD on the inhibition of cell growth, induction of apoptosis and inhibition of inflammation have now been demonstrated on a cellular level. Each of these activities supports beneficial effects in hyperproliferative skin disorders, such as psoriasis
Positively charged and pH self-buffering quantum dots for efficient cellular uptake by charge mediation and monitoring cell membrane permeability
Nanotechnology204
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