733 research outputs found
Clinical update on the therapeutic use of clopidogrel: treatment of acute ST-segment elevation myocardial infarction (STEMI)
The pathogenesis of ST-elevation myocardial infarction (STEMI) involves plaque disruption, platelet aggregation and intracoronary artery thrombus formation. Aspirin is the cornerstone of antiplatelet therapy in patients with STEMI, reducing the risk of recurrent myocardial infarction or death during the acute phase and long term by about one-quarter. Recent large randomized trials have demonstrated that the addition of clopidogrel to aspirin reduces the risk of major ischemic events by up to a further one-third in patients with STEMI treated with fibrinolytic therapy and undergoing percutaneous coronary intervention, with no significant increase in bleeding. Thus, dual antiplatelet therapy with the combination of clopidogrel and aspirin is becoming the new standard of care for the management of patients with STEMI
Computed tomographic angiographic imaging of abdominal aortic aneurysms: implications for transfemoral endovascular aneurysm management
Computed tomographic angiographic imaging of abdominal aortic aneurysms: implications for transfemoral endovascular aneurysm management
PURPOSE: To describe anatomic features pertinent to patient selection and graft design for transfemoral endovascular aneurysm management (TEAM) of the infrarenal aorta using computed tomographic (CT) angiography. METHODS: A prospective noncomparative analysis of 102 spiral CT scans of the abdominal aorta of patients with abdominal aortic aneurysms was performed. From the original CT data set, slices were reconstructed perpendicular to the vessel axis (central lumen line) at a 10 mm interval. In these reconstructed slices, diameter measurements were performed. Vessel length was measured along the central lumen line. In each patient possibilities for TEAM were analyzed. RESULTS: Because of technical reasons, 36 scans were excluded from the analysis. Of the remaining 66 patients, 18 could potentially be treated with a bifurcated endovascular device. The infrarenal aortic diameter-to-iliac artery diameter ratio was less than 2 in most patients. The vessel segments judged to be adequate for endovascular graft anchoring had a noncylindrical shape in the majority of cases. CONCLUSION: Only a minority of patients with abdominal aortic aneurysms can at this stage be treated with an endovascular graft. The ideal endovascular graft should be a combination of rigid and flexible components. The proximal and distal attachment systems should have some flexibility with an intrinsic maximum diameter while the midsection of the graft can be relatively rigi
The impact of hunting on tropical mammal and bird populations
Hunting is a major driver of biodiversity loss, but a systematic large-scale estimate of hunting-induced defaunation is lacking. We synthesized 176 studies to quantify hunting-induced declines of mammal and bird populations across the tropics. Bird and mammal abundances declined by 58% (25 to 76%) and by 83% (72 to 90%) in hunted compared with unhunted areas. Bird and mammal populations were depleted within 7 and 40 kilometers from hunters’ access points (roads and settlements). Additionally, hunting pressure was higher in areas with better accessibility to major towns where wild meat could be traded. Mammal population densities were lower outside protected areas, particularly because of commercial hunting. Strategies to sustainably manage wild meat hunting in both protected and unprotected tropical ecosystems are urgently needed to avoid further defaunation
Study of 16 Portuguese activated sludge systems based on filamentous bacteria populations and their relationships with environmental parameters
A survey in 16 activated sludge waste water treatment plants (WWTP) was conducted to contribute to the knowledge of the environmental parameters that determine the composition of the filamentous community. A total of 128 samples of mixed liquor from municipal WWTP were collected during 2 years, and 22 filamentous morphotypes were identified. The most frequent and abundant filamentous bacteria were, in both cases and by this order, type 0041/0675, type 0092, Microthrix parvicella and 1851, nocardioforms and Haliscomenobacter hydrossis. Concerning dominance, type 1851 was the most frequently dominant morphotype, followed by M. parvicella and types 0092 and 0041/0675. These were also, and by this order, the dominant morphotypes during bulking occurrences. Significant correlations were obtained between the abundance of filamentous bacteria and environmental parameters, but multivariate statistical analysis only confirmed the correlation between type 0092 and Sludge Volume Index (SVI), emphasizing the association of this filament with bulking. The discussion of the results in light of published works was complicated by the random use of terms such as frequency, abundance, and dominance with different and often unclear meanings. This reinforces the need of clarifying these terms when discussing the causes of filamentous overgrowth in WWTP.Portuguese Foundation for Science and Technology (FCT) and the European Community fund FEDER, through Program COMPETE, in the ambit of the Projects
FCOMP-01-0124-FEDER-007025 (PTDC/AMB/68393/2006), PEst-OE/EQB/LA0023/2013, RECI/BBB-EBI/0179/2012 (FCOMP-01-0124-FEDER-027462), and the Project BBioEnv - Biotechnology and
Bioengineering for a sustainable world,REF. NORTE-07-0124-
FEDER-000048, co-funded by the Programa Operacional Regional do
Norte (ON.2 – O Novo Norte), QREN, FEDER. PhD grant SFRH/BD/64848/200
Verslag workshops Friese Veenweidevisie
Waterschap en provincie werken aan een Veenweidevisie voor Friesland. In de Veenweidevisie vormt de zorg over de toenemende snelheid van de maaivelddaling en het verlies van de veenbodem een centraal aandachtspunt. Voor het verkennen van de problemen en oplossingen zijn streekbijeenkomsten georganiseerd. Drie scenario’s zijn voor de toekomst van de veenweiden in Friesland beschreven. Deze drie scenario’s zijn voor drie voorbeeldgebieden, Hommerts, Grote Veenpolder en het Buitenveld, uitgewerkt in drie workshops
Exploratory study of plasma total homocysteine and its relationship to short-term outcome in acute ischaemic stroke in Nigerians
<p>Abstract</p> <p>Background</p> <p>Hyperhomocysteinemia is a potentially modifiable risk factor for stroke, and may have a negative impact on the course of ischaemic stroke. The role of hyperhomocysteinemia as it relates to stroke in Africans is still uncertain. The objective of this study was to determine the prevalence and short-term impact of hyperhomocysteinemia in Nigerians with acute ischaemic stroke. We hypothesized that Hcy levels are significantly higher than in normal controls, worsen stroke severity, and increase short-term case fatality rates following acute ischaemic stroke.</p> <p>Methods</p> <p>The study employed both a case-control and prospective follow-up design to study hospitalized adults with first – ever acute ischaemic stroke presenting within 48 hours of onset. Clinical histories, neurological evaluation (including National Institutes of Health Stroke Scale (NIHSS) scores on admission) were documented. Total plasma Hcy was determined on fasting samples drawn from controls and stroke cases (within 24 hours of hospitalization). Outcome at 4 weeks was assessed in stroke patients using the Glasgow Outcome Scale (GOS).</p> <p>Results</p> <p>We evaluated 155 persons (69 acute ischaemic stroke and 86 healthy controls). The mean age ± SD of the cases was 58.8 ± 9.8 years, comparable to that of controls which was 58.3 ± 9.9 years (T = 0.32; P = 0.75). The mean duration of stroke (SD) prior to hospitalization was 43.5 ± 38.8 hours, and mean admission NIHSS score was 10.1 ± 7.7. Total fasting Hcy in stroke patients was 10.2 ± 4.6 umol/L and did not differ significantly from controls (10.1 ± 3.6 umol/L; P = 0.88). Hyperhomocysteinemia, defined by plasma Hcy levels > 90<sup>th </sup>percentile of controls (>14.2 umol/L in women and >14.6 umol/L in men), was present in 7 (10.1%) stroke cases and 11 (12.8%) controls (odds ratio 0.86, 95% confidence interval 0.31 – 2.39; P > 0.05). In multiple regression analysis admission NIHSS score (but not plasma Hcy) was a significant determinant of 4 week outcome measured by GOS score (P < 0.0001).</p> <p>Conclusion</p> <p>This exploratory study found that homocysteine levels are not significantly elevated in Nigerians with acute ischaemic stroke, and admission Hcy level is not a determinant of short-term (4 week) stroke outcome.</p
Distribution characteristics of air-bone gaps : evidence of bias in manual audiometry
OBJECTIVES : Five databases were mined to examine distributions of airbone
gaps obtained by automated and manual audiometry. Differences
in distribution characteristics were examined for evidence of influences
unrelated to the audibility of test signals.
DESIGN : The databases provided air- and bone-conduction thresholds
that permitted examination of air-bone gap distributions that were free
of ceiling and floor effects. Cases with conductive hearing loss were
eliminated based on air-bone gaps, tympanometry, and otoscopy, when
available. The analysis is based on 2,378,921 threshold determinations
from 721,831 subjects from five databases.
RESULTS : Automated audiometry produced air-bone gaps that were normally
distributed suggesting that air- and bone-conduction thresholds
are normally distributed. Manual audiometry produced air-bone gaps
that were not normally distributed and show evidence of biasing effects
of assumptions of expected results. In one database, the form of the
distributions showed evidence of inclusion of conductive hearing losses.
CONCLUSIONS : Thresholds obtained by manual audiometry show tester
bias effects from assumptions of the patient’s hearing loss characteristics.
Tester bias artificially reduces the variance of bone-conduction
thresholds and the resulting air-bone gaps. Because the automated
method is free of bias from assumptions of expected results, these distributions
are hypothesized to reflect the true variability of air- and boneconduction
thresholds and the resulting air-bone gaps.Portions of this work were supported by Grant RC3DC010986 from the
National Institute of Deafness and Other Communication Disorders and
by contract No. VA118-12-C-0029 from the US Department of Veterans
Affairs. The Rehabilitation Research and Development Service of the US
Department of Veterans Affairs supported this work through the Auditory
and Vestibular Dysfunction Research Enhancement Award Program
(REAP) and a Senior Research Career Scientist award to the second author.http://journals.lww.com/ear-hearing2017-03-31hb2016Speech-Language Pathology and Audiolog
Distribution characteristics of normal pure-tone thresholds
OBJECTIVE : This study examined the statistical properties of normal air-conduction thresholds obtained with automated and manual audiometry
to test the hypothesis that thresholds are normally distributed and to examine the distributions for evidence of bias in manual
testing. DESIGN : Four databases were mined for normal thresholds. One contained audiograms obtained with an automated method. The
other three were obtained with manual audiometry. Frequency distributions were examined for four test frequencies (250, 500, 1000,
and 2000 Hz). STUDY SAMPLE : The analysis is based on 317 569 threshold determinations of 80 547 subjects from four clinical databases.
RESULTS : Frequency distributions of thresholds obtained with automated audiometry are normal in form. Corrected for age, the mean
thresholds are within 1.5 dB of reference equivalent threshold sound pressure levels. Frequency distributions of thresholds obtained by
manual audiometry are shifted toward higher thresholds. Two of the three datasets obtained by manual audiometry are positively skewed.
CONCLUSIONS : The positive shift and skew of the manual audiometry data may result from tester bias. The striking scarcity of thresholds
below 0 dB HL suggests that audiologists place less importance on identifying low thresholds than they do for higher-level thresholds.
We refer to this as the Good enough bias and suggest that it may be responsible for differences in distributions of thresholds obtained by
automated and manual audiometry.By grant RC3DC010986 from the National Institutes of Deafness and Other Communication Disorders. The Rehabilitation Research and Development Service of the U.S. Department of Veterans Affairs supported this work through the
Auditory and Vestibular Dysfunction Research Enhancement Award Program (REAP) and a Senior Research Career Scientist.http://www.tandfonline.com/loi/iija202016-05-31hb2016Speech-Language Pathology and Audiolog
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