442 research outputs found

    Gender differences in health status and adverse outcomes among patients with peripheral arterial disease

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    BACKGROUND: Few studies have examined gender differences in health status and cardiovascular outcomes in patients with peripheral artery disease (PAD). This study assessed (1) self-reported health status at PAD diagnosis and 12-months later, and explored (2) whether outcomes in women with PAD differ with regard to long-term major adverse events. METHODS AND RESULTS: A total of 816 patients (285 women) with PAD were enrolled from 2 vascular clinics in the Netherlands. Baseline clinical data and subsequent adverse events were recorded and patients completed the Short Form-12 (SF-12, Physical Component Score [PCS] and Mental Component Score [MCS]) upon PAD diagnosis and 12-months later. Women had similar ages and clinical characteristics, but poorer socio-economic status and more depressive symptoms at initial diagnosis, as compared with men. Women also had poorer physical (PCS: 37±10 versus 40±10, P=0.004) and mental ( MCS: 47±12 versus 49±11, P=0.005) health status at the time of presentation. At 12-months, women still reported a poorer overall PCS score (41±12 versus 46±11, P=0.006) and MCS score (42±14 versus 49±12, P=0.002). Female gender was an independent determinant of a poorer baseline and 12-month PCS and MCS scores. However, there were no significant differences by gender on either mortality (unadjusted hazard ratio [HR]=0.93, 95% CI 0.60;1.44, P=0.74) or major adverse events (unadjusted HR=0.90, 95% CI 0.63;1.29, P=0.57), after a median follow-up of 3.2 years. CONCLUSIONS: Women's physical and mental health status is compromised both at initial PAD diagnosis and at 12-month follow-up, despite experiencing a similar magnitude of change in their health scores throughout the first 12-months after diagnosis.Rachel P. Dreyer, Moniek van Zitteren, John F. Beltrame, Robert Fitridge, Johan Denollet, Patrick W. Vriens, John A. Spertus, Kim G. Smoldere

    Scaling and Formulary cross sections for ion-atom impact ionization

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    The values of ion-atom ionization cross sections are frequently needed for many applications that utilize the propagation of fast ions through matter. When experimental data and theoretical calculations are not available, approximate formulas are frequently used. This paper briefly summarizes the most important theoretical results and approaches to cross section calculations in order to place the discussion in historical perspective and offer a concise introduction to the topic. Based on experimental data and theoretical predictions, a new fit for ionization cross sections is proposed. The range of validity and accuracy of several frequently used approximations (classical trajectory, the Born approximation, and so forth) are discussed using, as examples, the ionization cross sections of hydrogen and helium atoms by various fully stripped ions.Comment: 46 pages, 8 figure

    Clinical considerations for the treatment of secondary differentiated thyroid carcinoma in childhood cancer survivors

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    The incidence of differentiated thyroid carcinoma (DTC) has increased rapidly over the past several years. Thus far, the only conclusively established risk factor for developing DTC is exposure to ionizing radiation, especially when the exposure occurs in childhood. Since the number of childhood cancer survivors (CCS) is increasing due to improvements in treatment and supportive care, the number of patients who will develop DTC after surviving childhood cancer (secondary thyroid cancer) is also expected to rise. Currently, there are no recommendations for management of thyroid cancer specifically for patients who develop DTC as a consequence of cancer therapy during childhood. Since complications or late effects from prior cancer treatment may elevate the risk of toxicity from DTC therapy, the medical history of CCS should be considered carefully in choosing DTC treatment. In this paper, we emphasize how the occurrence and treatment of the initial childhood malignancy affects the medical and psychosocial factors that will play a role in the diagnosis and treatment of a secondary DTC. We present considerations for clinicians to use in the management of patients with secondary DTC, based on the available evidence combined with experience -based opinions of the authors

    [F-18]FDG-PET/CT to prevent futile surgery in indeterminate thyroid nodules:a blinded, randomised controlled multicentre trial

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    Purpose To assess the impact of an [F-18]FDG-PET/CT-driven diagnostic workup to rule out malignancy, avoid futile diagnostic surgeries, and improve patient outcomes in thyroid nodules with indeterminate cytology. Methods In this double-blinded, randomised controlled multicentre trial, 132 adult euthyroid patients with scheduled diagnostic surgery for a Bethesda III or IV thyroid nodule underwent [F-18]FDG-PET/CT and were randomised to an [F-18] FDG-PET/CT-driven or diagnostic surgery group. In the [F-18]FDG-PET/CT-driven group, management was based on the [F-18]FDG-PET/CT result: when the index nodule was visually [F-18]FDG-positive, diagnostic surgery was advised; when [F-18]FDG-negative, active surveillance was recommended. The nodule was presumed benign when it remained unchanged on ultrasound surveillance. In the diagnostic surgery group, all patients were advised to proceed to the scheduled surgery, according to current guidelines. The primary outcome was the fraction of unbeneficial patient management in one year, i.e., diagnostic surgery for benign nodules and active surveillance for malignant/borderline nodules. Intention-to-treat analysis was performed. Subgroup analyses were performed for non-Hurthle cell and Hurthle cell nodules. Results Patient management was unbeneficial in 42% (38/91 [95% confidence interval [CI], 32-53%]) of patients in the [F-18] FDG-PET/CT-driven group, as compared to 83% (34/41 [95% CI, 68-93%]) in the diagnostic surgery group (p < 0.001). [F-18]FDG-PET/CT-driven management avoided 40% (25/63 [95% CI, 28-53%]) diagnostic surgeries for benign nodules: 48% (23/48 [95% CI, 33-63%]) in non-Hurthle cell and 13% (2/15 [95% CI, 2-40%]) in I-Liable cell nodules (p = 0.02). No malignant or borderline tumours were observed in patients under surveillance. Sensitivity, specificity, negative and positive predictive value, and benign call rate (95% CI) of [F-18]FDG-PET/CT were 94.1% (80.3-99.3%), 39.8% (30.0-50.2%), 95.1% (83.5-99.4%), 35.2% (25.4-45.9%), and 31.1% (23.3-39.7%), respectively. Conclusion An [F-18]FDG-PET/CT-driven diagnostic workup of indeterminate thyroid nodules leads to practice changing management, accurately and oncologically safely reducing futile surgeries by 40%. For optimal therapeutic yield, application should be limited to non-Hurthle cell nodules

    Increased susceptibility to cardiovascular effects of dihydrocapcaicin in resuscitated rats. Cardiovascular effects of dihydrocapsaicin

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    <p>Abstract</p> <p>Background</p> <p>Survivors of a cardiac arrest often have persistent cardiovascular derangements following cardiopulmonary resuscitation including decreased cardiac output, arrhythmias and morphological myocardial damage. These cardiovascular derangements may lead to an increased susceptibility towards the external and internal environment of the cardiovascular system as compared to the healthy situation.</p> <p>Methods</p> <p>Here we tested the hypothesis that the cardiovascular system in healthy rats and rats resuscitated from a cardiac arrest may be differentially affected by a transient receptor potential vanilloid type 1 agonist, by continuous intravenous infusion of dihydrocapsaicin (DHC).</p> <p>Results</p> <p>Compared to baseline, infusion of DHC caused an initial increase in mean arterial blood pressure in both healthy and resuscitated rats of 25% and 10%, respectively. Also, we observed an initial response of tachycardia in both healthy and resuscitated rats of 30% and 20%, respectively. Then, at high levels of DHC infusion (> 2.0 mg/kg/hr) we observed two single episodes of transient bradycardia and hypotension in 33% of the healthy rats, which was consistent with a TRPV1 agonist induced Bezold-Jarisch reflex. In contrast, in resuscitated rats we observed multiple episodes of bradycardia/hypotension in 100% of the rats and at a dose of DHC of 0.65 mg/kg/hr. Notably, this DHC effect could be completely blocked in the resuscitated rats by pre-treatment with atropine, a muscarinic acetylcholine antagonist.</p> <p>Conclusions</p> <p>Our results indicate that the susceptibility of the rats towards TRPV1 agonist induced Bezold-Jarisch reflex is increased in those resuscitated from cardiac arrest compared to the healthy situation.</p

    Interdomain Interactions Control Ca2+-Dependent Potentiation in the Cation Channel TRPV4

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    Several Ca2+-permeable channels, including the non-selective cation channel TRPV4, are subject to Ca2+-dependent facilitation. Although it has been clearly demonstrated in functional experiments that calmodulin (CaM) binding to intracellular domains of TRP channels is involved in this process, the molecular mechanism remains elusive. In this study, we provide experimental evidence for a comprehensive molecular model that explains Ca2+-dependent facilitation of TRPV4. In the resting state, an intracellular domain from the channel N terminus forms an autoinhibitory complex with a C-terminal domain that includes a high-affinity CaM binding site. CaM binding, secondary to rises in intracellular Ca2+, displaces the N-terminal domain which may then form a homologous interaction with an identical domain from a second subunit. This represents a novel potentiation mechanism that may also be relevant in other Ca2+-permeable channels
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