Home About us Contact
|
Home About us Contact | ||
|
|
||
First Event (first + event)
Selected AbstractsBiventricular Versus Right Ventricular Pacing in Patients with AV Block (BLOCK HF): Clinical Study Design and RationaleJOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 9 2007ANNE B. CURTIS M.D. Background: Right ventricular (RV) pacing restores ventricular systole in patients with atrioventricular (AV) block, yet recent studies have suggested that in patients with AV block and left ventricular (LV) dysfunction, RV pacing may exacerbate the progression to heart failure (HF). BLOCK HF is a prospective, multi-center, randomized, double-blind, controlled trial designed to determine whether patients with AV block, LV dysfunction (EF , 50%), and mild to moderate HF (NYHA I-III) who require pacing benefit from biventricular (BiV) pacing, compared with RV pacing alone. Objective: The primary objective of this trial is to determine whether the time to first event (all-cause mortality, heart failure-related urgent care, or a , 15% increase in left ventricular end systolic volume index [LVESVI]) for patients with BiV pacing is superior to that of patients with RV pacing. Methods: Patients with AV block and LV dysfunction who require permanent pacing and undergo successful implantation of a commercial Medtronic CRT device, with or without an ICD, will be randomized to BiV or RV pacing. Patients are followed at least every 6 months until study closure. Up to 1,636 patients may be enrolled in 150 centers worldwide. Conclusion: BLOCK HF is a large, randomized, clinical study in pacing-indicated patients with AV block, mild to moderate HF symptoms, and LV dysfunction to determine whether BiV pacing is superior to RV pacing in slowing the progression of HF. [source] Renal transplant recipients are at high risk for both symptomatic and asymptomatic deep vein thrombosisJOURNAL OF THROMBOSIS AND HAEMOSTASIS, Issue 5 2006D. POLI Summary.,Background:,Venous thromboembolism (VTE) is one of the thrombotic complications that can occur in patients receiving renal transplantation (RT). The prevalence of VTE in RT patients is, however, undefined. Objectives: To evaluate the rate of a first episode of VTE in a series of 538 consecutive RT recipients admitted to our institution, the timing of occurrence of the thromboembolic events after transplantation, and the rate of recurrence after thromboprophylaxis withdrawal. Risk factors for recurrence were also evaluated, particularly in relation to the type of the first event (symptomatic or asymptomatic). Results:,During follow-up, 47 of 518 patients (28 males, 19 females; 9.1%) developed a first episode of VTE at a median time of 17 months (range 1,165 months) after kidney transplantation. Cancer was associated with the occurrence of VTE (odds ratio 4.8). Seventeen of 43 patients (39.5%) with deep vein thrombosis were asymptomatic and the diagnosis was made during routine ultrasound examination. Twenty-two patients (46.8%) experienced a recurrence of VTE. A relevant rate of recurrence was documented amongst patients with a first episode of both symptomatic (53%) and asymptomatic (23.5%) VTE. Conclusion:,This study confirms that RT patients are at high risk of symptomatic and asymptomatic VTE and that this risk persists even after several years. Patients who experience VTE are at high risk of recurrence after thromboprophylaxis withdrawal. [source] Job categories and acute ischemic heart disease: a hospital-based, case-control study in TaiwanAMERICAN JOURNAL OF INDUSTRIAL MEDICINE, Issue 6 2007Jong-Dar Chen MD Abstract Background Most studies of the relationship between work and acute ischemic heart disease (IHD) were performed in western populations, and the extent to which their findings hold in Asian populations is largely unknown. The purpose of this study was to examine the association between job categories and non-fatal, first episodes of acute IHD in Taipei, Taiwan. Methods A hospital-based, case-control design was used. Cases were patients with a first episode of non-fatal acute IHD who were admitted to the department of cardiology. Two controls without known cardiovascular disease were matched to each case for age, gender, and date of admission. A total of 119 cases and 238 controls were enrolled between April and September 2004. Results Compared with white-collar workers, blue-collar workers had a 5.3-fold (95% CI: 1.5, 18.5) increased risk of a first episode of non-fatal acute IHD, while self-employed workers and managers/professionals had a slightly lower odds ratio of 0.6 (95% CI: 0.1, 2.4) and 0.5 (95% CI: 0.1, 2.2), respectively. Hypertension, diabetes, obesity, physical inactivity, and sleep disturbance were significant risk factors for acute IHD. A clustering of the cardiovascular risk factors was found in blue-collar workers. Conclusions Blue-collar workers had a 5.3-fold increased risk of a first event of non-fatal acute IHD compared with white-collar workers, and this increased risk was associated with a clustering of cardiovascular risk factors. Am. J. Ind. Med. 50:409,414, 2007. © 2007 Wiley-Liss, Inc. [source] Children's memory of recurring events: is the first event always the best remembered?APPLIED COGNITIVE PSYCHOLOGY, Issue 2 2003Martine B. Powell Three experiments were conducted to examine the effect of age (4,5 and 6,8 years) and retention interval on children's ability to remember separate occurrences of a repeated event that varied in terms of content (items, dialog, etc.) Experiment 1 explored children's ability to recall the first versus last occurrence of a series of six events, at either one week or six weeks delay. Experiments 2 and 3 explored children's ability to identify the position of items in terms of their order of presentation within the series across two retention intervals. Overall, the results revealed clear age differences in children's performance. In general, the 6- to 8-year-old children performed better on all tasks than the 4- to 5-year-old children. Further, the older children showed relatively good memory of the first and last items compared to the middle items, although the last items were more likely to be forgotten or misplaced in the sequencing tasks over time than the first items. For the younger children, the patterns of results were sometimes but not always consistent with that of the older children. The relevance and generalisability of these findings to the legal setting are discussed as well as directions for future research. Copyright © 2002 John Wiley & Sons, Ltd. [source] High plasma levels of factor VIII and risk of recurrence of venous thromboembolismBRITISH JOURNAL OF HAEMATOLOGY, Issue 4 2004Legnani Cristina Summary The aim of this study was to evaluate the relationship between factor VIII (FVIII) levels, measured by chromogenic and clotting assays, and risk of venous thromboembolism (VTE) recurrence. A total of 564 patients underwent clinical follow-up after oral anticoagulant withdrawal (total follow-up = 924·4 years). Recurrent VTE developed in 39 of 309 (12·6%) patients with a first idiopathic VTE and in 14 of 255 (5·5%) patients whose first event was secondary. In patients with a first idiopathic VTE, the risk of recurrence was more than fivefold higher in patients with FVIII levels exceeding the 90th percentile [chromogenic FVIII: relative risk (RR) 5·43 (95% CI 1·76,16·8); clotting FVIII: RR 6·21 (95% CI 1·57,24·5)] after adjustment for all possible confounding variables. In patients with a first secondary VTE, the risk of recurrence was slightly higher in patients with high FVIII levels [chromogenic FVIII: RR 2·62 (95% CI 0·34,19·9); clotting FVIII: RR 1·74 (95% CI 0·25,12·1)], but, given the low number of recurrences, the 95% CI were very large. In conclusion, this study shows that high FVIII levels are associated with increased risk of VTE recurrence in patients with a first idiopathic VTE. Although the measurement of FVIII levels by a specific chromogenic assay might, in principle, be preferred to avoid the risk of aspecific clotting effects, no significant differences in results obtained by chromogenic or clotting methods were found. [source] Zoledronic acid delays the onset of skeletal-related events and progression of skeletal disease in patients with advanced renal cell carcinomaCANCER, Issue 5 2003Allan Lipton M.D. Abstract BACKGROUND The objective of this study was to assess the efficacy and safety of zoledronic acid in patients with bone metastases secondary to renal cell carcinoma (RCC). METHODS A retrospective subset analysis of patients with RCC enrolled in a multicenter, randomized, placebo-controlled study of zoledronic acid was performed. Patients were randomized to receive zoledronic acid (4 or 8 mg as a 15-minute infusion) or placebo with concomitant antineoplastic therapy every 3 weeks for 9 months. The primary efficacy analysis was the proportion of patients with one or more skeletal-related events (SREs), which were defined as pathologic fracture, spinal cord compression, radiation therapy, or surgery to bone. Secondary analyses included time to first SRE, skeletal morbidity rate (events per year), disease progression, and multiple event analysis. RESULTS In this subset of 74 patients with RCC, zoledronic acid (4 mg) was found to significantly reduce the proportion of patients with an SRE (37% vs. 74% for placebo; P = 0.015). Similarly, zoledronic acid significantly reduced the mean skeletal morbidity rate (2.68 vs. 3.38 for placebo; P = 0.014) and extended the time to the first event (median not reached vs. 72 days for placebo; P = 0.006). A multiple event analysis demonstrated that the risk of developing an SRE was reduced by 61% compared with placebo (hazard ratio of 0.394; P = 0.008). The median time to progression of bone lesions was significantly longer for patients who were treated with zoledronic acid (P = 0.014 vs. placebo). Zoledronic acid appeared to be well tolerated; the most common adverse events in all treatment groups included bone pain, nausea, anemia, and emesis. CONCLUSIONS Zoledronic acid (4 mg as a 15-minute infusion) demonstrated significant clinical benefit in patients with bone metastases from RCC, suggesting that further investigation of zoledronic acid in this patient population is warranted. Cancer 2003;98:962,9. © 2003 American Cancer Society. DOI 10.1002/cncr.11571 [source] Folding Dynamics of 10-Residue ,-Hairpin Peptide ChignolinCHEMISTRY - AN ASIAN JOURNAL, Issue 5 2007Atsushi Suenaga Dr. Abstract Short peptides that fold into ,-hairpins are ideal model systems for investigating the mechanism of protein folding because their folding process shows dynamics typical of proteins. We performed folding, unfolding, and refolding molecular dynamics simulations (total of 2.7,,s) of the 10-residue ,-hairpin peptide chignolin, which is the smallest ,-hairpin structure known to be stable in solution. Our results revealed the folding mechanism of chignolin, which comprises three steps. First, the folding begins with hydrophobic assembly. It brings the main chain together; subsequently, a nascent turn structure is formed. The second step is the conversion of the nascent turn into a tight turn structure along with interconversion of the hydrophobic packing and interstrand hydrogen bonds. Finally, the formation of the hydrogen-bond network and the complete hydrophobic core as well as the arrangement of side-chain,side-chain interactions occur at approximately the same time. This three-step mechanism appropriately interprets the folding process as involving a combination of previous inconsistent explanations of the folding mechanism of the ,-hairpin, that the first event of the folding is formation of hydrogen bonds and the second is that of the hydrophobic core, or vice versa. [source] Direct parametric inference for the cumulative incidence functionJOURNAL OF THE ROYAL STATISTICAL SOCIETY: SERIES C (APPLIED STATISTICS), Issue 2 2006Jong-Hyeon Jeong Summary., In survival data that are collected from phase III clinical trials on breast cancer, a patient may experience more than one event, including recurrence of the original cancer, new primary cancer and death. Radiation oncologists are often interested in comparing patterns of local or regional recurrences alone as first events to identify a subgroup of patients who need to be treated by radiation therapy after surgery. The cumulative incidence function provides estimates of the cumulative probability of locoregional recurrences in the presence of other competing events. A simple version of the Gompertz distribution is proposed to parameterize the cumulative incidence function directly. The model interpretation for the cumulative incidence function is more natural than it is with the usual cause-specific hazard parameterization. Maximum likelihood analysis is used to estimate simultaneously parametric models for cumulative incidence functions of all causes. The parametric cumulative incidence approach is applied to a data set from the National Surgical Adjuvant Breast and Bowel Project and compared with analyses that are based on parametric cause-specific hazard models and nonparametric cumulative incidence estimation. [source] | ||||||||||