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Upper Quartile (upper + quartile)
Selected AbstractsFactors affecting vocabulary acquisition at age 2 in children born between 23 and 28 weeks' gestationDEVELOPMENTAL MEDICINE & CHILD NEUROLOGY, Issue 8 2007Louise Marston MSc Language development is often slower in preterm children compared with their term peers. We investigated factors associated with vocabulary acquisition at 2 years in a cohort of children born at 28 weeks' gestation or less. For children entered into the United Kingdom Oscillation Study, language development was evaluated by using the MacArthur-Bates Communicative Development Inventories score, completed by parents as part of a developmental questionnaire. The effect of demographic, neonatal, socioeconomic factors, growth, and disability were investigated using multifactorial random effects modelling. Questionnaires were returned by 288 participants (148 males, 140 females). The mean number of words vocalized was 42 (SD 29). Multifactorial analysis showed only four factors were significantly associated with vocabulary acquisition. These were: (1) level of disability (mean words: no disability, 45; other disability, 38; severe disability, 30 [severe disability is defined as at least one extreme response in one of the following clinical domains: neuromotor, vision, hearing, communication, or other physical disabilities]; 95% confidence interval [CI] for the difference between no and severe disability 7- 23); (2) sex (39 males, 44 females; 95% CI 0.4-11); (3) length of hospital stay (lower quartile, 47; upper quartile, 38; 95% CI -12 to -4); and (4) weight SD score at 12 months (lower quartile, 39; upper quartile, 44; 95% CI 1,9). There was no significant association between gestational age and vocabulary after multifactorial analysis. There was no significant effect of any socioeconomic factor on vocabulary acquisition. We conclude that clinical factors, particularly indicators of severe morbidity, dominate the correlates of vocabulary acquisition at age 2 in children born very preterm. [source] Spatial point-process statistics: concepts and application to the analysis of lead contamination in urban soil,ENVIRONMETRICS, Issue 4 2005Christian Walter Abstract This article explores the use of spatial point-process analysis as an aid to describe topsoil lead distribution in urban environments. The data used were collected in Glebe, an inner suburb of Sydney. The approach focuses on the locations of punctual events defining a point pattern, which can be statistically described through local intensity estimates and between-point distance functions. F -, G - and K -surfaces of a marked spatial point pattern were described and used to estimate nearest distance functions over a sliding band of quantiles belonging to the marking variable. This provided a continuous view of the point pattern properties as a function of the marking variable. Several random fields were simulated by selecting points from random, clustered or regular point processes and diffusing them. Recognition of the underlying point process using variograms derived from dense sampling was difficult because, structurally, the variograms were very similar. Point-event distance functions were useful complimentary tools that, in most cases, enabled clear recognition of the clustered processes. Spatial sampling quantile point pattern analysis was defined and applied to the Glebe data set. The analysis showed that the highest lead concentrations were strongly clustered. The comparison of this data set with the simulation confidence limits of a Poisson process, a short-radius clustered point process and a geostatistical simulation showed a random process for the third quartile of lead concentrations but strong clustering for the data in the upper quartile. Thus the distribution of topsoil lead concentrations over Glebe may have resulted from several contamination processes, mainly from regular or random processes with large diffusion ranges and short-range clustered processes for the hot spots. Point patterns with the same characteristics as the Glebe experimental pattern could be generated by separate additive geostatistical simulation. Spatial sampling quantile point patterns statistics can, in an easy and accurate way, be used complementarily with geostatistical methods. Copyright © 2005 John Wiley & Sons, Ltd. [source] Why is soluble intercellular adhesion molecule-1 related to cardiovascular mortality?EUROPEAN JOURNAL OF CLINICAL INVESTIGATION, Issue 1 2002A. Becker Increased plasma levels of soluble adhesion molecules are associated with an increased risk of atherothrombosis. The pathophysiological mechanisms responsible for these associations are not known. The aim of the present study was to investigate the association of soluble intercellular adhesion molecule-1 (sICAM-1) concentration and risk of cardiovascular and all-cause mortality among individuals with and without type 2 diabetes. In addition, we assessed potential pathophysiological mechanisms by which sICAM-1 may promote mortality. Six hundred and thirty-one subjects taken from a general population of the middle-aged and elderly participated in this prospective cohort study. Baseline data collection was performed from 1989 to 1992; subjects were followed until 1 January 2000. Subjects who died had higher levels of sICAM-1 than those who survived (506(164) vs. 477(162) ng mL,1, respectively). After adjustment for age, gender and glucose tolerance status, subjects with sICAM-1 levels in the upper quartile (,550 ng mL,1) had a relative risk of cardiovascular mortality of 2·05 (95% confidence interval, 1·10,3·81) compared to subjects with sICAM-1 levels in the other quartiles. Further adjustment for classical cardiovascular risk factors or indicators of (sub)clinical atherosclerosis, endothelial dysfunction, inflammation and renal function did not materially alter this relative risk. A high sICAM-1 level was more frequent in subjects with type 2 diabetes than in subjects with a normal glucose tolerance (33·3 vs. 17·8%). Individuals with a plasma concentration of sICAM-1 higher than 550 ng mL,1 had a cardiovascular mortality risk that was twice that of individuals with a lower concentration. Classical cardiovascular risk factors (sub)clinical atherosclerosis, endothelial dysfunction and inflammation do not explain this excess risk. [source] The impact of non-stationarities in the climate system on the definition of ,a normal wind year': a case study from the BalticINTERNATIONAL JOURNAL OF CLIMATOLOGY, Issue 6 2005S. C. Pryor Abstract Wind speeds over the Baltic significantly increased over the second half of the 20th century (C20th), with the majority of the increase being focused on the upper quartile of the wind speed distribution and in the southwest of the region. These changes have potentially profound implications for the wind energy resource. For example, based on the National Centers for Environmental Prediction,National Center for Atmospheric Research (NCEP,NCAR) reanalysis data it is shown that, owing to this non-stationarity, using the normalization period of 1987,98 to determine the wind resource (as in the Danish wind index) leads to overestimation of the wind energy index (and hence the wind energy resource) in western Denmark relative to 1958,2001 by approximately 10%. To address whether the increased prevalence of high wind speeds at the end of the C20th will be maintained in the future, we provide a first prognosis of annual wind indices from the HadCM3 coupled atmosphere,ocean general circulation model. The results suggest the 21st century (C21st) will be similar to the 1958,2001 period with respect to the wind energy density, but that the northeastern Baltic will exhibit slightly higher wind energy indices over the course of the C21st relative to the latter half of the C20th, whereas the southwest of the Baltic exhibits some evidence of declining wind indices towards the end of the C21st. These changes may indicate a tendency in HadCM3 towards more northerly tracking of mid-latitude cyclones in the future, possibly due to evolution of the North Atlantic oscillation. As a caveat to this finding, it should be noted that the NCEP,NCAR and European Centre for Medium-Range Weather Forecasts reanalysis data sets and HadCM3 simulations, although exhibiting commonalities during the period of overlap, differ quantitatively in terms of the spatial fields and empirical cumulative probability distributions at individual grid cells. Copyright © 2005 Royal Meteorological Society [source] Long-term trends in near-surface flow over the BalticINTERNATIONAL JOURNAL OF CLIMATOLOGY, Issue 3 2003S. C. Pryor Abstract We report an analysis of trends in 850 hPa wind speed, as manifest in the NCEP,NCAR reanalysis fields, over the Baltic region during the latter half of the 20th century. The results indicate that annual mean wind speeds over the Baltic significantly increased over the period 1953,99 with the majority of the increase being associated with increases in the upper quartile of the wind speed distribution. Accordingly, much of the change is focused on the winter season. The trends in annual and seasonal mean wind speeds are greatest in relative and absolute sense in the southwest of the Baltic basin, where they are in excess of 0.25 m s,1 per decade for the annual mean. The extremes of the wind-speed distribution also increased by up to 5 m s,1 over the study period for the wind speed with a 50 year return period, again with the largest magnitude changes in the southwestern Baltic. These changes in wind speed are strongly linked to changes in the synoptic-scale circulation. The majority of the increase in wintertime wind speeds is attributable to an increase in westerly anticyclonic, westerly cyclonic and northwesterly cyclonic circulation types as manifest in the Grosswetterlagen catalogue, which are in turn related to the recent prevalence of the positive phase of the North Atlantic oscillation. Copyright © 2003 Royal Meteorological Society [source] Cross-Sectional Evaluation of Bone Metabolism in Men,JOURNAL OF BONE AND MINERAL RESEARCH, Issue 9 2001P. Szulc Abstract There are relatively few data concerning age-related changes of bone turnover in men. The aim of the study was to evaluate age-related changes of the levels of serum and urinary biochemical markers of bone metabolism in a large cohort of 934 men aged 19,85 years and to investigate their association with bone mineral density (BMD). Bone formation was evaluated using serum levels of osteocalcin (OC), bone alkaline phosphatase (BAP), and N-terminal extension propeptide of type I collagen (PINP). Bone resorption was evaluated by measurement of urinary excretion of ,-isomerized C-terminal telopeptide of collagen type I (,-CTX) of free deoxypyridinoline (fDpyr) and total Dpyr (tDPyr) and of the serum level of ,-CTX. Levels of biochemical bone markers were very high in young men and decreased rapidly until the age of 40 years and then more slowly until 60 years of age. After the age of 60 years, markers of bone formation remained stable while resorption markers showed a moderate and variable increase with aging. Serum and urinary ,-CTX levels were elevated only in about 5% of elderly men. The age-related increase of urinary excretion of tDpyr and of its free and peptide-bound fractions was related to the presence of elevated levels in a subgroup of about 15% of elderly men. Before 60 years of age, levels of biochemical bone markers were not correlated with BMD, whereas after 60 years of age, they were correlated negatively with BMD. After adjustment for age and body weight, BMD in men with the highest levels of biochemical bone markers (i.e., in the upper quartile) was 1.8,12.5% (i.e., 0.25,0.89 SD) lower than in men with levels of biochemical bone markers in the lowest quartile. In conclusion, bone turnover in men is high in young adults and decreases to reach a nadir at 55,60 years of age. After the age of 60 years, bone resorption markers,but not bone formation markers,increase in some men and are associated with lower BMD, suggesting that this imbalance is responsible for increasing bone loss in elderly men. [source] Uncoupled and surviving: individual mice with high metabolism have greater mitochondrial uncoupling and live longerAGING CELL, Issue 3 2004John R. Speakman Summary Two theories of how energy metabolism should be associated with longevity, both mediated via free-radical production, make completely contrary predictions. The ,rate of living-free-radical theory' (Pearl, 1928; Harman, 1956; Sohal, 2002) suggests a negative association, the ,uncoupling to survive' hypothesis (Brand, 2000) suggests the correlation should be positive. Existing empirical data on this issue is contradictory and extremely confused (Rubner, 1908; Yan & Sohal, 2000; Ragland & Sohal, 1975; Daan et al., 1996; Wolf & Schmid-Hempel, 1989]. We sought associations between longevity and individual variations in energy metabolism in a cohort of outbred mice. We found a positive association between metabolic intensity (kJ daily food assimilation expressed as g/body mass) and lifespan, but no relationships of lifespan to body mass, fat mass or lean body mass. Mice in the upper quartile of metabolic intensities had greater resting oxygen consumption by 17% and lived 36% longer than mice in the lowest intensity quartile. Mitochondria isolated from the skeletal muscle of mice in the upper quartile had higher proton conductance than mitochondria from mice from the lowest quartile. The higher conductance was caused by higher levels of endogenous activators of proton leak through the adenine nucleotide translocase and uncoupling protein-3. Individuals with high metabolism were therefore more uncoupled, had greater resting and total daily energy expenditures and survived longest , supporting the ,uncoupling to survive' hypothesis. [source] Bed Stability and Sedimentation Associated With Human Disturbances in Pacific Northwest Streams,JOURNAL OF THE AMERICAN WATER RESOURCES ASSOCIATION, Issue 2 2009Philip R. Kaufmann Abstract:, To evaluate anthropogenic sedimentation in United States (U.S.) Pacific Northwest coastal streams, we applied an index of relative bed stability (LRBS*) to summer low flow survey data collected using the U.S. Environmental Protection Agency's Environmental Monitoring and Assessment Program field methods in a probability sample of 101 wadeable stream reaches. LRBS* is the log of the ratio of bed surface geometric mean particle diameter (Dgm) to critical diameter (D*cbf) at bankfull flow, based on a modified Shield's criterion for incipient motion. We used a formulation of LRBS* that explicitly accounts for reductions in bed shear stress that result from channel form roughness due to pools and wood. LRBS* ranged from ,1.9 to +0.5 in streams within the lower quartile of human riparian and basin disturbance, and was substantially lower (,4.2 to ,1.1) in streams within the upper quartile of human disturbance. Modeling results suggest that the expected range of LRBS* in streams without human disturbances in this region might be generally between ,0.7 and +0.5 in either sedimentary or volcanic lithology. However, streams draining relatively soft, erodible sedimentary lithology showed greater reductions in LRBS* associated with disturbance than did those having harder, more resistant volcanic (basalt) lithology with similar levels of basin and riparian disturbance. At any given level of disturbance, smaller streams had lower LRBS* than those with larger drainages. In sedimentary lithology (sandstone and siltstone), high-gradient streams had higher LRBS* than did low-gradient streams of the same size and level of human disturbance. High gradient streams in volcanic lithology, in contrast, had lower LRBS* than low-gradient streams of similar size and disturbance. Correlations between Dgm and land disturbance were stronger than those observed between D*cbf and land disturbance. This pattern suggests that land use has augmented sediment supplies and increased streambed fine sediments in the most disturbed streams. However, we also show evidence that some of the apparent reductions in LRBS*, particularly in steep streams draining small volcanic drainages, may have resulted in part from anthropogenic increases in bed shear stress. The synoptic survey methods and designs we use appear adequate to evaluate regional patterns in bed stability and sedimentation and their general relationship to human disturbances. More precise field measurements of channel slope, cross-section geometry, and bed surface particle size would be required to use LRBS* in applications requiring a higher degree of accuracy and precision, such as site-specific assessments at individual streams. [source] Factors associated with radiation exposure in patients with inflammatory bowel diseaseALIMENTARY PHARMACOLOGY & THERAPEUTICS, Issue 11-12 2009Z. LEVI Summary Background, Inflammatory bowel disease (IBD) patients undergo multiple radiological evaluations. Aim, To estimate total and abdominal radiation exposure from diagnostic X-ray investigations in IBD patients and the associated risk factors. Methods, Patients with Crohn's disease (CD) or ulcerative colitis (UC) treated in the IBD clinic were recruited. Clinical data were extracted from patient files and radiological data were obtained from the central HMO computer data base. Results, A total of 199 CD and 125 UC patients were included. The mean cumulative estimated doses (CED) for CD and UC were 21.1 ± 19.5 and 15.1 ± 20.4 millisieverts (mSv) respectively (P < 0.001). Twenty-three patients (7.1%) had an estimated CED of ,50 mSv. In multivariate analyses, predictors of increased CED were: surgery (OR 5.68, 95% CI: 2.73,11.8, P < 0.001), CD (OR 2.56, 95% CI: 1.29,5.07, P = 0.007), prednisone use (OR 2.0, 95% CI: 1.11,3.67, P = 0.02), first year of disease (OR 6.4, 95% CI: 1.3,32, P = 0.02) and age in the upper quartile (OR 3.26, 95% CI: 1.68,6.3, P = 0.001). Conclusions, Diagnosis of CD, IBD-related surgery, prednisone use, first year of diagnosis and age on the upper quartile are independent predictors of increased exposure in IBD patients. Alternative investigations which do not require radiation exposure should be considered for patients at risk for increased radiation exposure. [source] Neopterin and interleukin-8 , prognosis in alcohol-induced cirrhosisLIVER INTERNATIONAL, Issue 6 2000Christian Homann Abstract:Background: Neutrophil cytotoxity and activated macrophages have been implicated in the pathogenesis of alcohol-induced liver disease. The aim of this study was to relate plasma levels of neopterin, a marker of activation of the cellular immune system, and IL-8, a neutrophil chemotactic factor, with severity of liver disease and prognosis in patients with alcohol-induced cirrhosis. Methods: Plasma concentrations of neopterin and IL-8 were assessed in 81 patients with alcohol-induced cirrhosis admitted to the Department of Medicine B, Bispebjerg Hospital, Copenhagen, Denmark, and in 16 healthy controls. After a median follow-up period of 5 years, mortality and death causes were registered. The patients were divided into groups according to the major contributing cause of death: infection, upper gastrointestinal bleeding or hepatic coma. Results: Neopterin and IL-8 levels were increased in the cirrhosis patients, but not significantly related to Child-Pugh classification. Five-year mortality was 67%. High neopterin levels (>upper quartile) were an independent predictor of death (p=0.01, Log rank and p<0.02, Cox). High IL-8 levels (>upper quartile) were of no significant prognostic value for overall mortality. Causes of death related mortality were as follows (Log rank): Neopterin; p=0.009, p=0.84 and p=0.94, and IL-8; p=0.36, p=0.002 and p=0.27, respectively, according to infection, bleeding and coma as causes of death. Conclusions: Neopterin and IL-8 plasma levels are raised in patients with alcohol-induced cirrhosis, and are predictive of mortality associated with infections and upper gastrointestinal bleeding, respectively. [source] Influence of Glucose Control and Improvement of Insulin Resistance on Microvascular Blood Flow and Endothelial Function in Patients with Diabetes Mellitus Type 2MICROCIRCULATION, Issue 7 2005THOMAS FORST ABSTRACT Objective: The study was performed to investigate the effect of improving metabolic control with pioglitazone in comparison to glimepiride on microvascular function in patients with diabetes mellitus type 2. Methods: A total of 179 patients were recruited and randomly assigned to one treatment group. Metabolic control (HbA1c), insulin resistance (HOMA index), and microvascular function (laser Doppler fluxmetry) were observed at baseline and after 3 and 6 months. Results: HbA1c improved in both treatment arms (pioglitazone: 7.52 ± 0.85% to 6.71 ± 0.89%, p < .0001; glimepiride: 7.44 ± 0.89% to 6.83 ± 0.85%, p < .0001). Insulin-resistance decreased significantly in the pioglitazone group (6.15 ± 4.05 to 3.85 ± 1.92, p < .0001) and remained unchanged in the glimepiride group. The microvascular response to heat significantly improved in both treatment groups (pioglitazone 48.5 [15.2; 91.8] to 88.8 [57.6; 124.1] arbitrary units [AU], p < .0001; glimepiride 53.7 [14.1; 91.9] to 87.9 [52.9, 131.0] AU, p < .0001, median [lower and upper quartile]). Endothelial function as measured with the acetylcholine response improved in the pioglitazone group (38.5 [22.2; 68.0] to 60.2 [36.9; 82.8], p = .0427) and remained unchanged in the glimepiride group. Conclusions: Improving metabolic control has beneficial effects in microvascular function in type 2 diabetic patients. Treatment of type 2 diabetic patients with pioglitazone exerts additional effects on endothelial function beyond metabolic control. [source] Solar UVR exposures of indoor workers in a Working and a Holiday Period assessed by personal dosimeters and sun exposure diariesPHOTODERMATOLOGY, PHOTOIMMUNOLOGY & PHOTOMEDICINE, Issue 6 2001E. Thieden Background/Aim: The aim of this study was to quantify ultraviolet radiation (UVR) exposure of fully employed indoor workers during a Working Period and a Holiday Period in the summer months. A further aim was to investigate the correlation between individual personal UVR dosimeter reading and self-reported data in a diary about sun exposure habits and to investigate whether skin type, age and gender influence sun exposure. Methods: The solar UVR, in standard erythema doses (SED) measured by UV sensitive spore-film filter type personal dosimeters (VioSpor®), and sun exposure diaries were compared. The study included 44 healthy Danish adult indoor workers during a Working Period of a mean of 13 days and a Holiday Period of a mean of 17 days from June to September. Results: The individual total UVR exposure correlated significantly (P<0.001) in both the Holiday and Working Periods with individual total hours spent outdoors from 07:00 to 19:00 and with skin area exposure hours. There was no significant correlation between sun exposure dose and gender, age or skin type I-IV, or between the individual solar exposure dose in the Working and the Holiday Period. However, subjects with UVR exposures in the upper quartile spent their Holiday Period in Southern Europe, and/or had been more than the mean time outdoors at the beach/sea and/or between 12:00 and 15:00. Subjects with UVR exposure in the lower quartiles spent their holidays in Denmark or Northern Europe and did not stay at the beach at all. They received an average solar UVR dose which was 22% of ambient in Denmark in the same period while subjects having their holidays in Southern Europe received as much as 90% of the ambient dose in Denmark. Conclusions: Despite information campaigns to avoid the midday sun, on average 35% of the recorded hours outdoors were spent between 12:00 and 15:00 in the Holiday Period. Total hours outdoors give the best estimate of the total sun exposure dose. Registration in a diary of total hours outdoors and whether the Holiday Period was in Northern or Southern Europe can be used to predict the solar exposure dose in a Holiday Period of a few weeks. [source] Effort,reward imbalance at work and self-rated health of Las Vegas hotel room cleanersAMERICAN JOURNAL OF INDUSTRIAL MEDICINE, Issue 4 2010Niklas Krause MD Abstract Background This study investigates the relationship between effort-reward-imbalance (ERI) at work and self-rated health (SF-36) among 941 Las Vegas hotel room cleaners (99% female, 84% immigrant). Methods Logistic regression models adjust for age, health behaviors, physical workload and other potential confounders. Results 50% reported ERI and 60% poor or fair general health. Significant associations were found between ERI and all SF-36 health measures. Workers in the upper quartile of the efforts/rewards ratio were 2,5 times more likely to experience poor or fair general health, low physical function, high levels of pain, fatigue, and role limitations due to physical and mental health problems. Conclusions The cross-sectional design limits causal interpretation of these associations. However, the development of interventions to reduce ERI and to improve general health among room cleaners deserves high priority considering that both high ERI and low self-rated health have predicted chronic diseases and mortality in prospective studies. Am. J. Ind. Med. 53:372,386, 2010. © 2009 Wiley-Liss, Inc. [source] Reduced Blood Platelet Sensitivity to Aspirin in Coronary Artery Disease: Are Dyslipidaemia and Inflammatory States Possible Factors Predisposing to Sub-optimal Platelet Response to Aspirin?BASIC AND CLINICAL PHARMACOLOGY & TOXICOLOGY, Issue 5 2006Leszek Markuszewski Platelet non-responsiveness to aspirin is associated with an increased risk of serious cardiovascular events. Several environmental and hereditary factors are reportedly involved in sub-optimal acetylsalicylic acid response. Forty-five coronary artery disease patients and 45 non-coronary artery disease controls received acetylsalicylic acid at a daily dose of 75,150 mg. Controls were examined twice: on the day of entering the study and 10 days later. Urinary 11-dehydrothromboxane B2 was assessed as the marker of platelet thromboxane generation. Aggregation was studied in platelet-rich plasma using turbidimetric aggregometry with collagen and arachidonic acid. Fifty to seventy percent of coronary artery disease patients showed an extent of collagen-induced aggregation above the upper quartile of the reference range compared with 8,15% in controls (P<0.003). For arachidonic acid-activated aggregation these proportions were 45,50% in coronary artery disease versus 7% in controls (P<0.007). In coronary artery disease patients, the acetylsalicylic acid-mediated platelet inhibition positively correlated with increased triglycerides (in arachidonic acid-stimulated platelets, r=0.30, P=0.0018), total cholesterol (r=0.33, P<0.0001 in coll and arachidonic acid-activated platelets) and elevated serum C-reactive protein (CRP) (r=0.27, P=0.0024). In coronary artery disease patients urine 11-dehydrothromboxane B2 concentrations were significantly increased compared to controls after 10 day acetylsalicylic acid intake (563; 313,728 pg/mg creatinine versus 321; 246,488 pg/mg creatinine, P=0.04). The incidence of suboptimal acetylsalicylic acid response incidence was more common in patients with coronary artery disease. Acetylsalicylic acid inhibition of blood platelet reactivity and thromboxane generation was less effective in these patients. Dyslipidaemia and chronic inflammatory states may promote suboptimal acetylsalicylic acid response in coronary artery disease patients. [source] Quantification of intracellular homocysteine by stable isotope dilution liquid chromatography/tandem mass spectrometryBIOMEDICAL CHROMATOGRAPHY, Issue 1 2007Yuehua Huang Abstract A precise and accurate stable isotope dilution liquid chromatography/tandem mass spectrometry method for the analysis of intracellular homocysteine has been developed. An internal standard, [2H8]-homocystine, was added to cell pellets from EA.hy 926 cells grown in culture under low and high folate concentrations. d,l -dithiothreitol was used to reduce cellular homocystine to homocysteine. Cellular proteins were precipitated by the addition of formic acid in acetonitrile. After centrifugation, a portion of the supernatant was analyzed by liquid chromatography/tandem mass spectrometry. Using a Supelcosil cyano column with an Applied Biosystems API 4000 triple quadrupole mass spectrometer, the SRM transitions for homocysteine (m/z 136 to m/z 90) and [2H4]-homocysteine (m/z 140 to m/z 94) were monitored. The method was validated by conducting five replicate analyses on three different days at four different concentrations (concentrations at the lower limit of quantitation and expected lower quartile, mid-range and upper quartile). The limit of detection was 2 ng/106 EA.hy 926 cells. Using this method, the intracellular homocysteine concentration in EA.hy 926 cells ranged from 10 to 36 ng/106 cells. Copyright © 2006 John Wiley & Sons, Ltd. [source] Telomerase activity is prognostic in pediatric patients with acute myeloid leukemiaCANCER, Issue 9 2003Comparison with adult acute myeloid leukemia Abstract BACKGROUND Significantly elevated telomerase activity (TA) has been found in samples from patients with almost all malignant hematologic diseases. The impact of elevated TA on the course of pediatric patients with acute myeloid leukemia (P-AML) is unknown. METHODS Using a modified polymerase chain reaction-based, telomeric repeat-amplification protocol assay, the authors measured TA in bone marrow samples from 40 patients with P-AML and, for comparison, in 65 adult patients with AML (A-AML), excluding patients with French,American,British M3 disease. The results were correlated with patient characteristics and survival. RESULTS TA in patients with P-AML was significantly lower compared with TA in patients with A-AML (P = 0.005). Patients who had P-AML with low TA had a projected 5-year survival rate of 88%, whereas patients who had P-AML with high TA had a projected 5-year survival rate of 43% (P = 0.009). Conversely, patients who had A-AML with very high TA (upper quartile) had significantly longer survival compared with patients who had A-AML with lower TA (P = 0.03). There was no correlation between complete remission rate or disease free survival and TA in P-AML or A-AML. In the A-AML group, when patients were separated by cytogenetic findings (poor prognosis vs. others), it was found that TA was significantly lower in patients with a poor prognosis, but the prognostic value of TA was not independent of cytogenetic status. CONCLUSIONS The current results suggest, that for patients with P-AML, bone marrow TA is a highly significant prognostic factor. Cancer 2003;97:2212,7. © 2003 American Cancer Society. DOI 10.1002/cncr.11313 [source] TSH concentration within the normal range is associated with cognitive function and ADHD symptoms in healthy preschoolersCLINICAL ENDOCRINOLOGY, Issue 6 2007Mar Álvarez-Pedrerol Summary Objective, Thyroid hormone concentrations outside the normal range affect brain development, but their specific influence on behaviour and mental abilities within normal values is unknown. The objective of this study was to investigate whether thyroid hormone concentrations are related to neurodevelopment and ADHD (attention deficit and hyperactivity disorder) symptoms in healthy preschoolers. Design subjects and measurements, Children from two general population birth cohorts in Menorca (n = 289) and Ribera d'Ebre (n = 53), Spain, were assessed in a cross-sectional study at the age of 4. Thyroid hormones (free T4 and T3) and TSH concentrations were measured and mental and motor development was assessed using McCarthy's scales for neuropsychological outcomes and ADHD-DSM-IV for attention deficit and hyperactivity/impulsivity symptoms. Results, Children with TSH concentrations in the upper quartile of the normal range performed lower on McCarthy's scales and were at higher risk for attention deficit and hyperactivity/impulsivity symptoms. In the Menorca cohort, a decrease of 5·8 (P < 0·05) and 6·9 (P < 0·01) points was observed in memory and quantitative skills, respectively. In contrast, high T4 concentrations were associated with decreased risk of having 1,5 attention deficit symptoms (odds ratio: 0·25; P < 0·01); these findings were observed in both cohorts despite differences in mean TSH concentrations. No associations were observed with T3. Conclusions, Despite being within the normal range, high TSH concentrations are associated with a lower cognitive function and high TSH and low free T4 with ADHD symptoms in healthy preschoolers. Statistically significant differences were observed in the highest quartiles of TSH, suggesting a need for re-evaluation of the upper limit of the normal TSH range. [source] Dietary carotenoids and risk of colon cancer: Case-control studyINTERNATIONAL JOURNAL OF CANCER, Issue 1 2004André Nkondjock Abstract Some epidemiological studies suggest that consumption of fruits and vegetables with a high carotenoid content may protect against colon cancer (CC). The evidence, however, is not completely consistent. Given the inconsistencies in findings in previous studies and continued interest in identifying modifiable risk factors for CC, a case-control study of French-Canadian in Montreal, Canada, was undertaken to examine the possible association between dietary carotenoids and CC risk and to investigate whether this association varies in relation to lifestyle factors such as smoking or diet, and particularly the high consumption of long-chain polyunsaturated fatty acids (LCPUFA). A total of 402 colorectal cases (200 males and 202 females) and 688 population-based controls matched for age, gender and place of residence were interviewed. Dietary intake was assessed through a validated food frequency questionnaire that collected information on over 200 food items and recipes. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated in unconditional logistic regression models. After adjustment for important variables such as total energy intake, no association was found between dietary intake of carotenoids and CC risk. For women with high intakes of LCPUFA, an inverse association was found between lutein + zeaxanthin and CC risk. ORs were 0.41; 95%CI (0.19,0.91), p=0.03 for eicosapentaenoic acid, and OR=0.36, 95%CI (0.19,0.78), p=0.01 for docosahexaenoic acid, when the upper quartiles of intake were compared to the lower. Among never-smokers, a significantly reduced risk of CC was associated with intake of ,-carotene [OR=0.44, 95%CI (0.21,0.92) and p=0.02], whereas an inverse association was found between lycopene intake and CC risk [OR=0.63, 95%CI (0.40,0.98) and p=0.05] among smokers. The results of our study suggest that a diet rich in both lutein + zeaxanthin and LCPUFAs may help prevent CC in French-Canadian females. © 2004 Wiley-Liss, Inc. [source] Using Dominance-Diversity Curves to Assess Completion Criteria After Bauxite Mining Rehabilitation in Western AustraliaRESTORATION ECOLOGY, Issue 1 2003C. D. Grant Abstract Dominance-diversity curves have been previously constructed for a range of ecosystems around the world to illustrate the dominance of particular species and show how their relative abundances compare between communities separated in time or space. We investigate the usefulness of dominance-diversity curves in rehabilitated areas to compare the floristic composition and abundance of "undisturbed" areas with disturbed areas, using bauxite mining rehabilitation in Western Australia as an example. Rehabilitated pits (11,13 years old) subjected to prescribed fire in autumn and spring were compared with unburned rehabilitated areas and the native jarrah (Eucalyptus marginata) forest. Dominance diversity curves were constructed by ranking the log of the species density values from highest to lowest. Species were categorized according to a variety of functional responses: life form (trees, shrubs, subshrubs, and annuals), fire response syndrome (seeder or resprouter), nitrogen fixing capability, and origin (native or adventive). Exponential functions showed extremely good fits for all sites (r2 = 0.939,0.995). Dominance diversity graphs showed that after burning of rehabilitated areas, sites exhibited a more similar dominance-diversity curve than before burning. This was emphasized in a classification (UPGMA) of the regression equations from the dominance-diversity curves that showed that sites burned in spring were more similar to the native forest than sites burned in autumn. There was no significant segregation of the nitrogen-fixing and species origin categories, although the life form and fire response groupings showed significant segregation along the dominance-diversity curve. Resprouters tended to be over-represented in the lower quartiles and under-represented in the upper quartiles of post-burn sites. It is suggested that using dominance-diversity curves in the monitoring of rehabilitated areas may be a useful approach because it provides an easily interpretable visual representation of both species richness and abundance relationships and may be further utilized to emphasize categories of plants that are over- or under-represented in rehabilitated areas. This will assist in the post-rehabilitation management of these sites. [source] | |||||||||||||