1,572 research outputs found
Incident venous thromboembolic events in the Prospective Study of Pravastatin in the Elderly at Risk (PROSPER)
<p>Background: Venous thromboembolic events (VTE), including deep venous thrombosis and pulmonary embolism, are common in older age. It has been suggested that statins might reduce the risk of VTE however positive results from studies of middle aged subjects may not be generalisable to elderly people. We aimed to determine the effect of pravastatin on incident VTE in older people; we also studied the impact of clinical and plasma risk variables.</p>
<p>Methods: This study was an analysis of incident VTE using data from the Prospective Study of Pravastatin in the Elderly at Risk (PROSPER), a randomized, double-blind, placebo-controlled trial of pravastatin in men and women aged 70-82. Mean follow-up was 3.2 years. Risk for VTE was examined in non-warfarin treated pravastatin (n = 2834) and placebo (n = 2865) patients using a Cox's proportional hazard model, and the impact of other risk factors assessed in a multivariate forward stepwise regression analysis. Baseline clinical characteristics, blood biochemistry and hematology variables, plasma levels of lipids and lipoproteins, and plasma markers of inflammation and adiposity were compared. Plasma markers of thrombosis and hemostasis were assessed in a nested case (n = 48) control (n = 93) study where the cohort was those participants, not on warfarin, for whom data were available.</p>
<p>Results: There were 28 definite cases (1.0%) of incident VTE in the pravastatin group recipients and 20 cases (0.70%) in placebo recipients. Pravastatin did not reduce VTE in PROSPER compared to placebo [unadjusted hazard ratio (95% confidence interval) 1.42 (0.80, 2.52) p = 0.23]. Higher body mass index (BMI) [1.09 (1.02, 1.15) p = 0.0075], country [Scotland vs Netherlands 4.26 (1.00, 18.21) p = 0.050 and Ireland vs Netherlands 6.16 (1.46, 26.00) p = 0.013], lower systolic blood pressure [1.35 (1.03, 1.75) p = 0.027] and lower baseline Mini Mental State Examination (MMSE) score [1.19 (1.01, 1.41) p = 0.034] were associated with an increased risk of VTE, however only BMI, country and systolic blood pressure remained significant on multivariate analysis. In a nested case control study of definite VTE, plasma Factor VIII levels were associated with VTE [1.52 (1.01, 2.28), p = 0.044]. However no other measure of thrombosis and haemostasis was associated with increased risk of VTE.</p>
<p>Conclusions: Pravastatin does not prevent VTE in elderly people at risk of vascular disease. Blood markers of haemostasis and inflammation are not strongly predictive of VTE in older age however BMI, country and lower systolic blood pressure are independently associated with VTE risk.</p>
Proximal ulna stress fracture and stress reaction of the proximal radius associated with the use of crutches: a case report and literature review
We report a case of complete stress fracture of the ulna and stress reaction of the radius resulting from the use of crutches in an overweight patient with severe lower extremity arthritis. Plain radiograph showed an undisplaced complete fracture of the proximal metaphysis of the ulna. Magnetic resonance imaging (MRI) was performed to exclude a pathological cause in view of the unusual fracture site, which confirmed the plain radiographic findings and additionally demonstrated a stress reaction in the proximal radius. There are three cases of stress fracture of the ulnar diaphysis resulting from the use of crutches reported previously in the English literature and a further case of bilaterally symmetrical ulnar diaphysial fracture reported in the Danish literature. We report the first case of ulnar metaphysis stress fracture with concomitant stress reaction of the radius
Implementation of nutritional guidelines in a university hospital monitored by repeated point prevalence surveys
Background/Objectives: Malnutrition is present in 20â50% of hospitalized patients, and nutritional care is a challenge. The aim was to evaluate whether the implementation of a nutritional strategy would influence nutritional care performance in a university hospital. Subjects/Methods: This was a prospective quality improvement program implementing guidelines for nutritional care, with the aim of improving nutritional practice. The Nutrition Risk Screening (NRS) 2002 was used. Point prevalence surveys over 2 years to determine whether nutritional practice had improved. Results: In total, 3604 (70%) of 5183 eligible patients were screened and 1230 (34%) were at nutritional risk. Only 53% of the at-risk patients got nutritional treatment and 5% were seen by a dietician. The proportion of patients screened increased from the first to the eighth point prevalence survey (P=0.012), but not the proportion of patients treated (P=0.66). The four initial screening questions in NRS 2002 identified 92% of the patients not at nutritional risk. Conclusions: Implementation of nutritional guidelines improved the screening performance, but did not increase the proportion of patients who received nutritional treatment. Point prevalence surveys were useful to evaluate nutritional practice in this university hospital. In order to improve practice, we suggest using only the four initial screening questions in NRS 2002 to identify patients not at risk, better education in nutritional care for physicians and nurses, and more dieticians employed. Audit of implementation of guidelines, performed by health authorities, and specific reimbursement for managing nutrition may also improve practice.publishedVersio
Variation of selfing rate and inbreeding depression among individuals and across generations within an admixed Cedrus population
[EN] We investigated the variation and short-term evolution of the selfing rate and inbreeding depression (ID) across three generations within a cedar forest that was established from admixture ca 1860. The mean selfing rate was 9.5%, ranging from 0 to 48% among 20 seed trees (estimated from paternally inherited chloroplast DNA). We computed the probability of selfing for each seed and we investigated ID by comparing selfed and outcrossed seeds within progenies, thus avoiding maternal effects. In all progenies, the germination rate was high (88-100%) and seedling mortality was low (0-12%). The germination dynamics differed significantly between selfed and outcrossed seeds within progenies in the founder gene pool but not in the following generations. This transient effect of selfing could be attributed to epistatic interactions in the original admixture. Regarding the seedling growth traits, the ID was low but significant: 8 and 6% for height and diameter growth, respectively. These rates did not vary among generations, suggesting minor gene effects. At this early stage, outcrossed seedlings outcompeted their selfed relatives, but not necessarily other selfed seedlings from other progenies. Thus, purging these slightly deleterious genes may only occur through within-family selection. Processes that maintain a high level of genetic diversity for fitness-related traits among progenies also reduce the efficiency of purging this part of the genetic load. Š 2011 Macmillan Publishers Limited All rights reserved.
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Subcoronary versus supracoronary aortic stenosis. an experimental evaluation
<p>Abstract</p> <p>Background</p> <p>Valvular aortic stenosis is the most common cause of left ventricular hypertrophy due to gradually increasing pressure work. As the stenosis develop the left ventricular hypertrophy may lead to congestive heart failure, increased risk of perioperative complications and also increased risk of sudden death. A functional porcine model imitating the pathophysiological nature of valvular aortic stenosis is very much sought after in order to study the geometrical and pathophysiological changes of the left ventricle, timing of surgery and also pharmacological therapy in this patient group.</p> <p>Earlier we developed a porcine model for aortic stenosis based on supracoronary aortic banding, this model may not completely imitate the pathophysiological changes that occurs when valvular aortic stenosis is present including the coronary blood flow. It would therefore be desirable to optimize this model according to the localization of the stenosis.</p> <p>Methods</p> <p>In 20 kg pigs subcoronary (n = 8), supracoronary aortic banding (n = 8) or sham operation (n = 4) was preformed via a left lateral thoracotomy. The primary endpoint was left ventricular wall thickness; secondary endpoints were heart/body weight ratio and the systolic/diastolic blood flow ratio in the left anterior descending coronary. Statistical evaluation by oneway anova and unpaired t-test.</p> <p>Results</p> <p>Sub- and supracoronary banding induce an equal degree of left ventricular hypertrophy compared with the control group. The coronary blood flow ratio was slightly but not significantly higher in the supracoronary group (ratio = 0.45) compared with the two other groups (subcoronary ratio = 0.36, control ratio = 0.34).</p> <p>Conclusions</p> <p>A human pathophysiologically compatible porcine model for valvular aortic stenosis was developed by performing subcoronary aortic banding. Sub- and supracoronary aortic banding induce an equal degree of left ventricular hypertrophy. This model may be valid for experimental investigations of aortic valve stenosis but studies of left ventricular hypertrophy can be studied equally well by graduated constriction of the ascending aorta.</p
ERBB4 confers metastatic capacity in Ewing sarcoma.
Metastatic spread is the single-most powerful predictor of poor outcome in Ewing sarcoma (ES). Therefore targeting pathways that drive metastasis has tremendous potential to reduce the burden of disease in ES. We previously showed that activation of the ERBB4 tyrosine kinase suppresses anoikis, or detachment-induced cell death, and induces chemoresistance in ES cell lines in vitro. We now show that ERBB4 is transcriptionally overexpressed in ES cell lines derived from chemoresistant or metastatic ES tumours. ERBB4 activates the PI3K-Akt cascade and focal adhesion kinase (FAK), and both pathways contribute to ERBB4-mediated activation of the Rac1 GTPase in vitro and in vivo. ERBB4 augments tumour invasion and metastasis in vivo, and these effects are blocked by ERBB4 knockdown. ERBB4 expression correlates significantly with reduced disease-free survival, and increased expression is observed in metastatic compared to primary patient-matched ES biopsies. Our findings identify a novel ERBB4-PI3K-Akt-FAK-Rac1 pathway associated with aggressive disease in ES. These results predict that therapeutic targeting of ERBB4, alone or in combination with cytotoxic agents, may suppress the metastatic phenotype in ES
The effect of continuous ultrasound on chronic low back pain: protocol of a randomized controlled trial
<p>Abstract</p> <p>Background</p> <p>Chronic non-specific low-back pain (LBP) is one of the most common and expensive musculoskeletal disorders in industrialized countries. Similar to other countries in the world, LBP is a common health and socioeconomic problem in Iran. One of the most widely used modalities in the field of physiotherapy for treating LBP is therapeutic ultrasound. Despite its common use, there is still inconclusive evidence to support its effectiveness in this group of patients. This randomised trial will evaluate the effectiveness of continuous ultrasound in addition to exercise therapy in patients with chronic LBP.</p> <p>Methods and design</p> <p>A total of 46 patients, between the ages 18 and 65 years old who have had LBP for more than three months will be recruited from university hospitals. Participants will be randomized to receive continuous ultrasound plus exercise therapy or placebo ultrasound plus exercise therapy. These groups will be treated for 10 sessions during a period of 4 weeks. Primary outcome measures will be functional disability and pain intensity. Lumbar flexion and extension range of motion, as well as changes in electromyography muscle fatigue indices, will be measured as secondary outcomes. All outcome measures will be measured at baseline, after completion of the treatment sessions, and after one month.</p> <p>Discussion</p> <p>The results of this trial will help to provide some evidence regarding the use of continuous ultrasound in chronic LBP patients. This should lead to a more evidence-based approach to clinical decision making regarding the use of ultrasound for LBP.</p> <p>Trial registration</p> <p>Netherlands Trial Register (NTR): <a href="http://www.trialregister.nl/trialreg/admin/rctview.asp?TC=2251">NTR2251</a></p
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