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Original Cohort (original + cohort)
Selected AbstractsP-Wave Indices, Distribution and Quality Control Assessment (from the Framingham Heart Study)ANNALS OF NONINVASIVE ELECTROCARDIOLOGY, Issue 1 2010Jared W. Magnani M.D. Background: P-wave indices of maximum P-wave duration and P-wave dispersion have been examined in a broad array of cardiovascular and noncardiovascular disease states. The P-wave indices literature has been highly heterogeneous in measurement methodologies, described quality control metrics, and distribution of values. We therefore sought to determine the reproducibility of P-wave indices in a community-based cohort. Methods: P-wave indices were measured in sequential subjects enrolled in the Framingham Heart Study. Electrocardiograms were obtained at the 11th biennial visit of the Original Cohort (n = 250) and the initial visit of the Offspring Cohort (n = 252). We determined the mean P-wave durations, interlead correlations, and P-wave indices. We then chose 20 ECGs, 10 from each cohort, and assessed intrarater and interrater variability. Results: The maximum P-wave duration ranged from 71 to 162 ms with mean of 112 ± 12 ms. The minimum P-wave duration ranged from 35 to 103 ms with mean of 65 ± 10 ms. P-wave dispersion ranged from 12 to 82 ms. The mean P-wave dispersion was 48 ± 12 ms (40,56). The intrarater intraclass correlation coefficient (ICC) was r = 0.80 for maximum P-wave duration and r = 0.82 for P-wave dispersion. The interrater ICC was 0.56 for maximum P-wave duration and 0.70 for P-wave dispersion. Conclusions: We demonstrated excellent intrarater reproducibility and fair interrater reproducibility for calculating P-wave indices. Reproducibility is frequently lacking in studies of P-wave indices, but is an essential component for the field's growth and epidemiologic contribution. Ann Noninvasive Electrocardiol 2010;15(1):77,84 [source] A multi-site Canadian perspective: examining the functional outcome from first-episode psychosisACTA PSYCHIATRICA SCANDINAVICA, Issue 2 2009N. M. Menezes Objective:, To examine factors contributing to variance in functional outcome in first-episode psychosis (FEP) following 1 year of treatment. Method:, Naturalistic 1-year follow-up of a FEP cohort (n = 200), from programs in four university centers in Ontario, Canada. Functional recovery was defined by ,Social and Occupational Functioning Assessment Scale' (SOFAS) score>60. Regression analysis examined the contribution of independent variables to variance in functional outcome. Results:, Twelve-month outcome measures were available for 76.5% of the original cohort. Of these, 70% reported being in school/work and in satisfactory relationships. The functional recovery rate was 51%, compared to 74% attaining symptomatic remission. The greatest contributors to variance in outcome were ongoing symptoms at 6 months and substance abuse comorbidity. Conclusion:, After 1 year of treatment, FEP patients show high rates of symptomatic remission and relatively lower rates of functional recovery. Symptoms and substance abuse contribute to variance in outcome. [source] Clinical prediction rules for bacteremia and in-hospital death based on clinical data at the time of blood withdrawal for culture: an evaluation of their development and useJOURNAL OF EVALUATION IN CLINICAL PRACTICE, Issue 6 2006Tsukasa Nakamura MD (Research Fellow) Abstract Rationale, aims and objectives, To develop clinical prediction rules for true bacteremia, blood culture positive for gram-negative rods, and in-hospital death using the data at the time of blood withdrawal for culture. Methods, Data on all hospitalized adults who underwent blood cultures at a tertiary care hospital in Japan were collected from an integrated medical computing system. Logistic regression was used for developing prediction rules followed by the jackknife cross validation. Results, Among 739 patients, 144 (19.5%) developed true bacteremia, 66 (8.9) were positive for gram-negative rods, and 203 (27.5%) died during hospitalization. Prediction rule based on the data at the time of blood withdrawal for culture stratified them into five groups with probabilities of true bacteremia 6.5, 9.6, 21.9, 30.1, and 59.6%. For blood culture positive for gram-negative rods, the probabilities were 0.6, 4.7, 8.6, and 31.7%, and for in-hospital death, those were 6.7, 15.5, 26.0, 35.5, and 56.1%. The area of receiver operating characteristic for true bacteremia, blood culture positive for gram-negative rods, and in-hospital death were 0.73, 0.64, and 0.64, respectively, in original cohort and 0.72, 0.64, and 0.64 in validation respectively. Conclusions, The clinical prediction rules are helpful for improved clinical decision making for bacteremia patients. [source] Changes of gastric mucosal architecture during long-term omeprazole therapy: results of a randomized clinical trialALIMENTARY PHARMACOLOGY & THERAPEUTICS, Issue 5 2006L. LUNDELL Summary Background, The impact of long-term acid suppression on the gastric mucosa remains controversial. Aim, To report further observations on an established cohort of patients with gastro-oesophageal reflux disease, after 7 years of follow-up. Methods, Of the original cohort randomized to either antireflux surgery or omeprazole, 117 and 98 patients remained in the medical and surgical arms, respectively. Gastric biopsies were taken at baseline and throughout the study. Results, Fifty-three antireflux surgery and 39 omeprazole-treated patients had Helicobacter pylori infection at randomization. Eighty-three omeprazole-treated and 60 antireflux surgery patients remained H. pylori negative over the 7 years, and no change was observed in mucosal morphology except for a change in endocrine cell population (linear and diffuse hyperplasia, P = 0.03). During the 7-year study many patients, who were initially H. pylori infected, had the infection eradicated leaving only 13 omeprazole and 12 antireflux surgery patients still infected. In these patients, omeprazole induced a deterioration of the mucosal inflammation scores (P = 0.01) with a numerical increase of glandular atrophy. Conclusions, Long-term omeprazole therapy does not alter the exocrine oxyntic mucosal morphology in H. pylori -negative patients, but mucosal endocrine cells appear to be under proliferative stimulation; in H. pylori -positive patients there are changes in mucosal inflammation and atrophy. [source] Mortality of workers employed in shoe manufacturing: An update,AMERICAN JOURNAL OF INDUSTRIAL MEDICINE, Issue 7 2006Everett J. Lehman MS Abstract Background In the late 1970s, the National Institute for Occupational Safety and Health identified two shoe manufacturing facilities where workers experienced relatively "pure" exposures to toluene. A mortality study was conducted through December 31, 1982. An original study did not detect elevated leukemia mortality but did detect increased lung cancer mortality. The present study is an update of the mortality of the original cohort. Methods The study cohort consisted of workers employed 1 month or more between 1940 and 1979 at two Ohio shoe manufacturing plants. Vital status was ascertained through December 31, 1999. Results Seven thousand eight hundred twenty eight workers, contributing 300,777 person years, were available for analysis. An excess of lung cancer deaths persisted with additional years of follow-up (SMR,=,1.36, 95% confidence interval (CI),=,1.19,1.54). Trend tests did not indicate a positive trend between lung cancer risk and duration of employment. Mortality from leukemia was not significantly elevated in the updated analysis. Conclusions Results indicate a possible association between lung cancer mortality and exposure to chronic, low-levels of organic solvents. Although the strength of this conclusion was weakened by the lack of increasing lung cancer risk in relation to duration of employment, other studies have supported this association. Am. J. Ind. Med. 49:535,546, 2006. Published 2006 Wiley-Liss, Inc. [source] ORIGINAL ARTICLE: Soluble Human Leukocyte Antigen-G Isoforms in Maternal Plasma in Early and Late PregnancyAMERICAN JOURNAL OF REPRODUCTIVE IMMUNOLOGY, Issue 5 2009Roberta Rizzo Problem Human Leukocyte Antigen (HLA)-G is a class Ib gene located in the human major histocompatibility complex (MHC). Several lines of investigation indicate that the HLA-G molecule is involved in the maternal acceptance of the semi-allogenic fetus during pregnancy and in the development of tolerance. Expression of soluble HLA-G (sHLA-G) is positively correlated with successful in vitro fertilization (IVF) treatments, and aberrant expression of HLA-G in certain complications of pregnancy, such as pre-eclampsia and spontaneous abortion, has been reported. The main purpose of this study was to investigate the levels of different soluble HLA-G isoforms in maternal plasma in early and late pregnancy. Method of study Soluble HLA-G (sHLA-G) can be detected in maternal blood, and in this study, two different isoforms of sHLA-G, namely sHLA-G1 generated by shedding of membrane-bound HLA-G1 and HLA-G generated by specific HLA-G transcripts, have been investigated early [median of 16.4 weeks of gestation (GW)] and late (median: 38.9 GW) in pregnancy in an original cohort of 580 pregnant Caucasian women. Results Lower concentrations of sHLA-G1 were found late in pregnancy (>32 GW) in a group of women with severe pre-eclampsia compared with controls with uncomplicated pregnancies (P = 0.029, PC = 0.09; Mann,Whitney; Logistic regression analysis: P = 0.024, OR = 0.920, 95% CI: 0.855,0.989). However, this was not the case with HLA-G5, and significantly more of the cases with severe pre-eclampsia had detectable plasma HLA-G5 compared with that of the control group (P = 0.013, PC = 0.04; Mann,Whitney). Similar findings were not observed in women with gestational hypertension or existing hypertension continuing into pregnancy. Furthermore, there was a trend toward lower maternal plasma sHLA-G1 in a group of women with premature birth (<37 GW) compared with that of the control group (P = 0.028, PC = 0.17; Mann,Whitney). On the contrary, HLA-G5 was lower in the control group compared with that in the premature group (P = 0.004, PC = 0.02; Mann,Whitney). Conclusion This study shows in line with other published studies that a high, detectable soluble HLA-G concentration in maternal plasma or serum is not mandatory for a successful pregnancy. However, complications during pregnancy, such as (severe) pre-eclampsia, spontaneous abortion, IUGR, and premature birth, are associated with a low or undetectable level of soluble HLA-G in the maternal blood circulation. Also, this study indicates that sHLA-G1 is the interesting soluble HLA-G isoform in pre-eclampsia, and that low or undetectable levels of HLA-G5 at the end of pregnancy seem to be associated with an uncomplicated normal pregnancy, whereas in severe pre-eclampsia and possibly other pregnancy complications, such as preterm birth and IUGR, the level of HLA-G5 is higher. [source] Host plant effects on the development and survivorship of the galling insect Neopelma baccharidis (Homoptera: Psyllidae)AUSTRAL ECOLOGY, Issue 3 2002M. M. Espírito-Santo Abstract In this study, the mortality factors acting upon the galling psyllid Neopelma baccharidis Burckhardt (Homoptera) caused by its host plant, Baccharis dracunculifolia De Candole (Asteraceae) were analysed. In March 1999, 982 galls of the same cohort were randomly marked on 109 individuals of B. dracunculifolia in the field. Galls were censused each month during their development, from April to August, and dead galls were collected and analysed for mortality factors. Gall dehiscence rates were calculated for each month. The major mortality source of N. baccharidis was gall dropping (13.2% of the original cohort), which is probably a normal outcome of previous mortality caused by the other factors observed in this study. Unknown factors killed 11.7% of this gall population and were ascribed to plant resistance during gall development. Empty galls represented 7.7% of the observed mortality and may be a consequence of egg retention or egg mortality/abortion related to variations in plant quality. Shoot mortality was high during the dry season and killed 7.5% of the galls, but this impact was minimized after the third month from gall formation due to the ability of nymphs to accelerate development and emerge from galls on dying shoots. However, the size of dehisced galls on dead shoots tended to be smaller, possibly affecting adult performance. Mortality of N. baccharidis attributed to B. dracunculifolia strongly controlled the galling insect population, killing 40.7% of the original cohort of galls. Plant-mediated mortality was caused by often neglected factors acting predominantly during the first 3 months of development, which are critical to gall survivorship. These results reinforce the importance of bottom-up forces in plant-insect systems. [source] Paramedic Self-efficacy and Skill Retention in Pediatric Airway ManagementACADEMIC EMERGENCY MEDICINE, Issue 12 2008Scott T. Youngquist MD Abstract Objectives:, The objectives were to determine the effect of pediatric airway management training on paramedic self-efficacy and skill performance and to determine which of several retraining methods is superior. Methods:, A total of 2,520 paramedics were trained to proficiency in pediatric bag-mask ventilation (BMV) and endotracheal intubation (ETI) on mannequins. Subjects were a convenience sample of 245 (10% of original cohort) presenting for voluntary retraining. A total of 212 of 245 (87%) completed skills testing. Self-efficacy was measured prior to and following initial training and retraining events. Paramedics were assigned to control (no retraining), videotape presentation, self-directed learning, or instructor-facilitated lecture and demonstration retraining. Following retraining, BMV and ETI skills were tested. Results:, Paramedics from low-call-volume areas reported lower baseline self-efficacy and derived larger increases with training, but also experienced the most decline between training events. Pass rates for BMV and ETI were 66% (139/211) and 42% (88/212), respectively. However, overall cohort self-efficacy was maintained over the study period. In ordinal regression modeling, only the lecture and demonstration method was superior to control, with an odds ratio (OR) of achieving higher scores of 2.5 (95% confidence interval [CI] = 1.2 to 5.2) for BMV and 5.2 (95% CI = 2.4 to 11.2) for ETI. Poor performance with ETI but not BMV was associated with time elapsed since training (p = 0.01). Self-efficacy ratings were not predictive of skill performance. Conclusions:, Training provides increases in self-efficacy, particularly among paramedics from low-call-volume areas. A gap exists between self-efficacy and skill performance, in that self-efficacy may be maintained even when skill performance declines. Pediatric airway skills decay quickly, ETI skills drop off more significantly than BMV skills, and a lecture and demonstration format seems superior to other retraining methods investigated. [source] The growth,mortality relationship in larval cohorts of Sardinops melanostictus, revealed by using two new approaches to analyse longitudinal data from otolithsJOURNAL OF FISH BIOLOGY, Issue 7 2008G. Plaza The growth,mortality relationship was assessed for larval cohorts of the Japanese sardine Sardinops melanostictus using two new approaches: (1) repeat measures in general linear model (RM-GLMs) and (2) the autoregressive-individual method (AIM). Both methods were compared to the traditional approach in which repeat-measure ANOVA was used to compare the changes in increment width (WI) at age and otolith radii (RO) at age between individuals from an original population and survivors. In RM-GLMs, both the WI at age and RO at age (i.e. at 5, 10, 15 and 20 days) were used as the dependent variables, and the standardized residuals of both regressions RO and age and RO and total length (LT), age class, and day of the year as independent variables. A significant increase in WI at age and RO at age from younger to older age classes was seen as indicative of growth-dependent selection. In AIM, the RO -at-age relationship for each fish was fitted for the first 20 days, using autoregression, and then the growth traits (i.e. slopes) between the original cohorts and survivors were compared using ANOVA. In the traditional approach, the WI at age and RO at age for the first 20 days of an original population were compared with those of survivors sampled in later stages. GLMs and traditional approaches supported the growth rate (i.e. the faster an individual grows, the higher its probability of survival) and bigger is better (i.e. larger individuals at any given age will have lower probability of mortality than smaller individuals of the same age) mechanisms. Furthermore, AIM showed that individuals from original cohorts had lower otolith growth rates than those from survivors, giving further support for the growth,mortality hypothesis for the larval stage of this clupeid. [source] | ||||||||||