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Z-score
Kinds of Z-score Selected AbstractsZ-Score for Benchmarking Reader Competence in a Central ECG LaboratoryANNALS OF NONINVASIVE ELECTROCARDIOLOGY, Issue 1 2009Gopi Krishna Panicker B.H.M.S., P.G.D.C.R. Background: ECGs from thorough QT studies must be read in a central laboratory by trained experts. Standards of expertise are not presently defined. We, therefore, studied the use of Z-scores to define reader competence. Methods: Two hundred ECGs were read by 24 experts and the mean and standard deviation (SD) of QT measurements calculated for each ECG. Z-scores ([QTreader, mean QTexperts]/ SDexperts) for each ECG and mean of absolute Z-scores of all ECGs read by a reader were calculated. The highest mean absolute Z-score of experts was considered the cutoff to define competence. Hundred of these standardized ECGs were used to assess performance of readers from the central laboratory. Results: All experts had mean absolute Z-scores , 1.5. Using this cutoff, one of 28 experienced readers and 7 of 15 trainees had unacceptable Z-scores. After re-training, all achieved Z-scores <1.5. Comparing histograms of actual Z-scores of the 100 ECGs of readers with unacceptable scores with that of the reader with the best Z-score showed two patterns. Readers with histograms having a peak and tails similar to that of the best reader, but with leftward or rightward shift, consistently made shorter or longer QT measurements, respectively. A histogram with a flatter peak and wider tails, suggested that measurements were long in some ECGs and short in others. Conclusion: Mean absolute Z-score is useful to assess competence for measuring the QT interval on ECGs. Analysis of histograms can pinpoint problems in QT measurements. [source] HMG-CoA reductase inhibitors prevent bone loss in patients with Type 2 diabetes mellitusDIABETIC MEDICINE, Issue 9 2004A. Nakashima Abstract Aims It has been reported that 3-hydroxy-3-methylglutaryl co-enzyme A (HMG-CoA) reductase inhibitors increase bone mineral density (BMD) in vivo. We investigated the effect of HMG-CoA reductase inhibitors on BMD in patients with Type 2 diabetes mellitus. Patients and methods We selected 122 patients with Type 2 diabetes, who were not taking active vitamin D preparations. Their mean age was 67.3 ± 9.2 years. They were divided into a control group (n = 63) without HMG-CoA reductase inhibitor therapy and an HMG-CoA group (n = 59) who were treated with these drugs. The BMD of the distal one-third of the radius was measured by dual-energy X-ray adsorptiometry at baseline and after 2 years. Results There were no significant differences between the control and HMG-CoA groups at baseline with respect to age, gender, body mass index, duration of diabetes, haemoglobin A1c, fasting plasma glucose, adjusted calcium, serum phosphorus, alkaline phosphatase, albumin excretion rate and radial BMD. However, there was a significantly smaller annual decrease of the radial BMD in the HMG-CoA group. Multiple regression analysis with a forward elimination procedure revealed a positive correlation of the radial BMD Z-score with body mass index, while there was a negative correlation with alkaline phosphatase and albumin excretion rate. In addition, the annual rate of change of the radial BMD showed a positive correlation with HMG-CoA reductase inhibitor therapy. Conclusions These findings suggest that HMG-CoA reductase inhibitors may prevent bone loss in patients with Type 2 diabetes. [source] Low bone mineral density in children and adolescents with inflammatory bowel disease: A population-based study from Western SwedenINFLAMMATORY BOWEL DISEASES, Issue 12 2009Susanne Schmidt MD Abstract Background: Low bone mineral density (BMD) has been recognized as a potential problem in children with inflammatory bowel disease (IBD). The aim of the study was to investigate BMD in Swedish children and adolescents with IBD and to evaluate possible factors affecting BMD. Methods: To evaluate BMD, all patients (n = 144) underwent a dual-energy X-ray absorptiometry (DXA) of the whole body and the spine. BMD values were expressed as Z-scores using normative pediatric data from Lunar (GE Medical Systems). Results: In this population-based study, the lowest BMD values were found in the lumbar spine. The entire IBD group showed significantly lower BMD Z-scores of the lumbar spine (L2,L4) in comparison to healthy references (,0.8 standard deviation [SD], range ,5.9 to 3.7 SD, P < 0.001). Decreased BMD with a Z-score < ,1 SD occurred in 46.7% of the individuals with Crohn's disease (CD) and in 47.0% of those with ulcerative colitis (UC). Low BMD with a Z-score , ,2 SD was present in 26.7% of the patients with CD and in 24.1% of the UC patients. In a multiple regression model with BMD lumbar spine as the depending variable, possible factors associated with lower BMD were male gender, low body mass index (BMI), and treatment with azathioprine. Conclusions: Low BMD is prevalent in Swedish pediatric patients with IBD. Possible risk factors for lower BMD are male gender, low BMI, and treatment with azathioprine, as a probable marker of disease course severity. (Inflamm Bowel Dis 2009) [source] Bone Health in Children and Adolescents After Renal Transplantation,,JOURNAL OF BONE AND MINERAL RESEARCH, Issue 10 2009Helena Valta MD Abstract The basis for lifelong bone health is established in childhood and adolescence. Whereas pediatric renal transplant (RTx) patients are at risk for impaired bone mass gain and fractures, scarce data on this subject are available. We performed a cross-sectional and longitudinal study of bone health in a national cohort of 106 pediatric RTx patients (median age, 12.6 yr; median follow-up, 5.1 yr after RTx). The patients underwent clinical evaluation, DXA for BMD, and spinal imaging for vertebral fractures. In longitudinal analysis, the median lumbar spine BMD Z-score was lowest (median, ,1.0) at 1 yr postoperatively but increased to a peak value of ,0.2 at 5 yr. In boys, the lumbar spine BMD Z-score increased also during puberty but decreased in girls. In cross-sectional analysis, the lumbar spine, hip, and whole body BMD Z-scores were < ,2 SD in 4%, 6%, and 6% of the patients, respectively. Sixteen percent had sustained peripheral fractures, and 8% had vertebral fractures. Female sex and age >15 yr (OR, 56.26; 95% CI, 5.17,611.82; p = 0.0007) as well as high plasma PTH levels (OR, 4.03; 95% CI, 1.37,11.85; p = 0.009) were significant predictors for low BMD. Three-year cumulative glucocorticoid dose, outside the immediate post-RTx years, was not associated with BMD parameters. The observed BMD results were satisfactory. However, the high (8%) prevalence of vertebral fractures warrants careful evaluation of bone health in these patients. [source] Five-year prospective analysis of dietary intake and clinical status in malnourished cystic fibrosis patientsJOURNAL OF HUMAN NUTRITION & DIETETICS, Issue 4 2003J. Walkowiak Abstract Background, Poor growth and malnutrition still pose a problem in cystic fibrosis (CF). The aim of the present study was to assess nutrition, as well as clinical status, of malnourished CF patients during a nutritional care programme. Material and methods, The study comprised 38 CF patients, aged 1,18 years old. The prospective annual assessment of dietary intake and clinical status was carried out during 1994,98. Results, The energy intake increased, in comparison with recommended daily allowances, from 83.6 ± 4.8% in 1994 to 107.9 ± 4.9% in 1998. A similar tendency was observed for the percentage of energy derived from fat (30.3 ± 0.8% versus 35.1 ± 0.8%) and protein (11.4 ± 0.4% versus 13.8 ± 0.4%). In subsequent years of the study, an improvement in the fat profile of the diet (with a higher consumption of polyunsaturated fatty acids) was observed. The observed increase of vitamin A and E consumption was related chiefly to changes in the doses of supplementation. During these 5 years, an improvement in nutritional status (Z-score: height ,1.34 ± 0.13 versus ,1.08 ± 0.14 and weight ,1.40 ± 0.09 versus ,1.12 ± 0.08) and lung function (forced expiratory volume in 1 s: 75.5 ± 2.0% versus 77.8 ± 2.2%) was observed. Conclusion, The nutritional care programme resulted in stable quantitative and qualitative changes in dietary intake. Although the diet does not reach the recommended level of high-energy intake, the positive impact of increasing nutrient intake on the nutritional and clinical status of malnourished CF patients was documented. [source] Quantitative analysis of MRI signal abnormalities of brain white matter with high reproducibility and accuracyJOURNAL OF MAGNETIC RESONANCE IMAGING, Issue 2 2002Xingchang Wei MD Abstract Purpose To assess the reproducibility and accuracy compared to radiologists of three automated segmentation pipelines for quantitative magnetic resonance imaging (MRI) measurement of brain white matter signal abnormalities (WMSA). Materials and Methods WMSA segmentation was performed on pairs of whole brain scans from 20 patients with multiple sclerosis (MS) and 10 older subjects who were positioned and imaged twice within 30 minutes. Radiologist outlines of WMSA on 20 sections from 16 patients were compared with the corresponding results of each segmentation method. Results The segmentation method combining expectation-maximization (EM) tissue segmentation, template-driven segmentation (TDS), and partial volume effect correction (PVEC) demonstrated the highest accuracy (the absolute value of the Z-score was 0.99 for both groups of subjects), as well as high interscan reproducibility (repeatability coefficient was 0.68 mL in MS patients and 1.49 mL in aging subjects). Conclusion The addition of TDS to the EM segmentation and PVEC algorithms significantly improved the accuracy of WMSA volume measurements, while also improving measurement reproducibility. J. Magn. Reson. Imaging 2002;15:203,209. © 2002 Wiley-Liss, Inc. [source] Linkage analysis of factor VIII and von Willebrand factor loci as quantitative trait lociJOURNAL OF THROMBOSIS AND HAEMOSTASIS, Issue 8 2003M. C. H. De Visser Summary., Elevated factor (F)VIII levels contribute to venous thrombotic risk. FVIII levels are determined to a large extent by levels of von Willebrand factor (VWF), its carrier protein which protects FVIII against proteolysis. VWF levels are largely dependent on ABO blood group. Subjects with blood group non-O have higher VWF and FVIII levels than individuals with blood group O. Apart from ABO blood group no genetic determinants of high FVIII levels have been identified, whereas clustering of FVIII levels has been reported within families even after adjustment for ABO blood group and VWF levels. We investigated the FVIII and VWF loci as possible quantitative trait loci (QTL) influencing FVIII and VWF levels. Two sequence repeats in the FVIII gene and three repeats in the VWF gene were typed in 52 FV Leiden families. Multipoint sib-pair linkage analysis was performed with the MAPMAKER/SIBS program. FVIII levels adjusted for VWF levels and age, and VWF levels adjusted for ABO blood group and age, were used for this linkage analysis. No linkage of FVIII levels to the FVIII locus was found, whereas we found evidence that the VWF locus contains a QTL for VWF levels [maximum likelihood no dominance variance lod score = 0.70 (P = 0.04) and non-parametric Z-score = 1.92 (P = 0.03)]. About 20% of the total variation in VWF levels may be attributed to this VWF locus. [source] Linear growth in early life is associated with suicidal ideation in 18-year-old FilipinosPAEDIATRIC & PERINATAL EPIDEMIOLOGY, Issue 5 2009Yin Bun Cheung Summary Studies in Western societies have shown some evidence that growth in early life may be associated with suicide and suicidal ideation in later life. The pattern of growth retardation in developing countries is different from that in Western societies. This study examines the association between size at birth, postnatal growth from birth to age 24 months and suicidal ideation in 18-year-old Filipinos. The 1941 participants born in 1983 and 1984 in the Philippines were assessed for growth status bimonthly from birth to 24 months of age and were administered an interview in 2002, which included items on suicidal ideation. The pattern of growth stunting in this cohort was similar to that in many other developing countries: a minor level of shortness in crown-heel length at birth followed by sharp decline in length-for-age in the first 24 months of life. The prevalence of suicidal ideation at age 18 was 2.9%; 95% confidence interval [CI] 2.2, 3.8%. Length Z-score at 24 months (odds ratios [OR] = 0.67; 95% CI [0.52, 0.86]; P = 0.002) and gain in length Z-score from birth to age 24 months (OR = 0.74; 95% CI [0.56, 0.98]; P = 0.037) were inversely associated with the odds of suicidal ideation. Adjustment for covariates made little difference. Length at birth Z-score was associated with suicidal ideation only after adjustment for postnatal length gain (OR = 0.61; 95% CI [0.46, 0.80]; P < 0.001). The associations between linear growth in early life and suicidal ideation appeared to be partly mediated by educational attainment. In conclusion, postnatal growth stunting is an important predictor of suicidal ideation in later life. It also affects the association between birth length and suicidal ideation. [source] Assessment and validation of bronchodilation using the interrupter technique in preschool children,PEDIATRIC PULMONOLOGY, Issue 7 2010Laura Mele Abstract Objective To determine and validate a cut-off value for bronchodilation using the interrupter resistance (Rint) in preschool children. Patients and Methods Rint was measured in 60 healthy children (age range 2.7,6.4 years) before and after salbutamol inhalation (200,µg). Four potential methods for assessing BDR were evaluated: percent change from baseline, percent change of predicted values, absolute change in Rint, and change in Z-score. These cut-off values, determined as the fifth percentile of the healthy group, were applied to children referred for the assessment of recurrent wheezing, classified on the basis of acute symptoms and/or abnormal chest examination into symptomatic (n,=,60, age range 2.9,6.1 years) and asymptomatic (n,=,60, age range 2.5,5.7 years) groups. Results The cut-off values for bronchodilation calculated in healthy children were: ,32% baseline; ,33% predicted; ,0.26,kPa L,1 sec; and ,1.25 Z-scores. Assessing BDR in children with a history of wheezing by either a decrease in absolute Rint or a decrease in Z-score gave sensitivity, specificity, negative predictive value, and positive predictive value all >80% for detecting children with current respiratory symptoms. Conclusions Both a decrease in Rint ,0.26,kPa L,1 sec and a decrease in Z-score of ,1.25 are appropriate for assessing BDR in preschool children with a history of recurrent wheezing. As Z-score is a more general solution, we recommend using a change in Z-score to determine BDR in preschool children. Further longitudinal studies will be required to determine the clinical utility of measuring BDR in managing lung disease in such children. Pediatr Pulmonol. 2010; 45:633,638. © 2010 Wiley-Liss, Inc. [source] Physiologic, bronchoscopic, and bronchoalveolar lavage fluid findings in young children with recurrent wheeze and cough,PEDIATRIC PULMONOLOGY, Issue 8 2006John Saito MD Abstract Assessing airway disease in young children with wheeze and/or cough is challenging. We conducted a prospective, descriptive study of lung function in children <3 years old with recurrent wheeze and/or cough, who had failed empiric antiasthma and/or antireflux therapy and subsequently underwent flexible bronchoscopy. Our goals were to describe radiographic, anatomical, microbiological, and physiological findings in these children, and generate hypotheses about their respiratory physiology. Plethysmography and raised-volume rapid thoracoabdominal compression (RVRTC) techniques were performed prior to bronchoscopy. Mean Z-scores (n,=,19) were ,1.34 for forced expiratory volume at 0.5 sec (FEV0.5), ,2.28 for forced expiratory flows at 75% of forced vital capacity (FVC) (FEF75), ,2.25 for forced expiratory flows between 25,75% of FVC (FEF25,75), 2.53 for functional residual capacity (FRC), and 2.23 for residual volume divided by total lung capacity (RV/TLC). Younger, shorter children had markedly depressed FEF75 and FEF25,75 Z-scores (P,=,0.002 and P,=,<0.001, respectively). As expected, lower airway anatomical abnormalities, infection, and inflammation were common. Elevated FRC was associated with anatomical lower airway abnormalities (P,=,0.03). FVC was higher in subjects with neutrophilic inflammation (P,=,0.03). There was no association between other physiologic variables and bronchoscopic/bronchoalveolar lavage fluid findings. Half of those with elevated RV/TLC ratios (Z-score >2) had no evidence of chest radiograph hyperinflation. We conclude that in this population, plethysmography and RVRTC techniques are useful in identifying severity of hyperinflation and airflow obstruction, and we hypothesize that younger children may have relatively small airways caliber, significantly limiting airflow, and thus impairing secretion clearance and predisposing to lower airway infection. Pediatr Pulmonol. 2006; 41: 709,719. © 2006 Wiley-Liss, Inc. [source] Pattern of growth after pediatric living-donor small bowel transplantationPEDIATRIC TRANSPLANTATION, Issue 6 2006Marian Porubsky Abstract:, The aim of our study was to analyze growth in children who underwent LDSB. The question was whether these children obtain linear growth and improvement of the Z-score for height and weight after the transplant. Three children with a mean age of 24 months underwent living-donor intestinal transplantation with 150 cm of terminal ileum. At a mean follow-up of 27 months height increased from 82.5 to 97.5 cm although Z-score for height did not improve, ,2.679 to ,2.675. Mean weight increased from 11.4 to 14.2 kg while Z-score for weight went from ,1.916 to ,2.409. Although these data are pertinent to only three children and the follow-up is slightly longer than two yr, it appears that while long-term survival and independency from TPN is achieved, only linear growth might be expected and catch-up growth does not occur. [source] Impaired Bone Health in Adolescents After Liver TransplantationAMERICAN JOURNAL OF TRANSPLANTATION, Issue 1 2008H. Valta Long-term complications related to immunosuppressive medication are an important problem after liver transplantation (OLT). This study was carried out to evaluate the bone health and risk factors for osteoporosis and fractures in 40 pediatric liver transplant recipients. The results of 208 longitudinal bone mineral density (BMD) measurements were analyzed retrospectively. In addition, a dual-energy X-ray absorptiometry was performed to assess the bone mineral content more precisely and to detect subclinical vertebral fractures (VF). The median age of the patients was 14 years and mean postoperative follow-up 7.0 years. The results showed that over half (58%) had lumbar spine (LS) Z-score ,,1.0 and one-fifth (18%) had asymptomatic VF. LS Z-score tended to increase from the first year after OLT, but during puberty the bone mass gain was suboptimal and Z-scores decreased in some subjects. Patients with VF were older at the time of OLT (p = 0.002) and their LS Z-score was lower (p = 0.001). Children transplanted before 10 years of age had less VF (p = 0.004) and higher LS Z-score (p = 0.005) than older patients. In conclusion, adolescent liver recipients are prone to osteoporosis and prevention should be targeted especially to this age group. [source] Z-Score for Benchmarking Reader Competence in a Central ECG LaboratoryANNALS OF NONINVASIVE ELECTROCARDIOLOGY, Issue 1 2009Gopi Krishna Panicker B.H.M.S., P.G.D.C.R. Background: ECGs from thorough QT studies must be read in a central laboratory by trained experts. Standards of expertise are not presently defined. We, therefore, studied the use of Z-scores to define reader competence. Methods: Two hundred ECGs were read by 24 experts and the mean and standard deviation (SD) of QT measurements calculated for each ECG. Z-scores ([QTreader, mean QTexperts]/ SDexperts) for each ECG and mean of absolute Z-scores of all ECGs read by a reader were calculated. The highest mean absolute Z-score of experts was considered the cutoff to define competence. Hundred of these standardized ECGs were used to assess performance of readers from the central laboratory. Results: All experts had mean absolute Z-scores , 1.5. Using this cutoff, one of 28 experienced readers and 7 of 15 trainees had unacceptable Z-scores. After re-training, all achieved Z-scores <1.5. Comparing histograms of actual Z-scores of the 100 ECGs of readers with unacceptable scores with that of the reader with the best Z-score showed two patterns. Readers with histograms having a peak and tails similar to that of the best reader, but with leftward or rightward shift, consistently made shorter or longer QT measurements, respectively. A histogram with a flatter peak and wider tails, suggested that measurements were long in some ECGs and short in others. Conclusion: Mean absolute Z-score is useful to assess competence for measuring the QT interval on ECGs. Analysis of histograms can pinpoint problems in QT measurements. [source] Association of higher adiposity and wheezing in infants with lower respiratory illnessesACTA PAEDIATRICA, Issue 9 2010Hye Mi Jee Abstract Aim:, The incidences of asthma and obesity have been steadily increasing over the past two decades, with several studies showing a relationship between these conditions. We investigated the influence of higher weight for height (WFH) Z-score on wheezing in infants with lower respiratory tract infections (LRTI). Methods:, We reviewed the medical charts of all infants younger than l year of age who were admitted with the first episode of LRTI between 2000 and 2008. Subjects were classified into six groups according to WFH Z-score. Results:, Wheezing was more frequent in infants with higher WFH Z-scores. Especially, wheezing infants aged 3,6 months and 6,9 months had significantly higher WFH Z-scores than had their non-wheezing counterparts (p = 0.05 and p < 0.01 respectively). Multivariate logistic regression showed that age (OR = 0.76, p < 0.001), male gender (OR = 1.61, p = 0.005) and WFH Z-score (OR = 1.12, p = 0.007) were independently associated with wheezing. Conclusion:, In this study we could show that a higher WFH Z-score was independently associated with wheezing in infancy. Attainment of appropriate weight for age may reduce the risk of wheezing in infants with respiratory diseases. [source] Children with chronic kidney disease: a 3-year prospective study of growth, bone mass and bone turnoverACTA PAEDIATRICA, Issue 2 2009Diana Swolin-Eide Abstract Aim: Children with chronic kidney disease (CKD) are at risk of developing skeletal problems. This 3-year prospective study investigated the development of bone mass and bone turnover in children with CKD. Methods: Fifteen patients, 4,15 years, were included with a median glomerular filtration rate of 48 (range 8,94) mL/min/1.73 m2. Bone mineral density (BMD) and markers of bone and mineral metabolism were investigated over a 3-year period. Results: Growth was satisfactory but a delayed bone age was observed. Total body bone mineral density (TBBMD) Z-scores were below zero in five patients at start and after 3 years, but none had a Z-score below ,2.5. Lumbar spine BMD Z-scores were below zero in three patients at start and in five patients after 3 years. The median TBBMD and lumbar spine Z-scores did not change during the study period. Eleven CKD patients had increased PTH levels at baseline and 13 patients after 3 years. Most children had normal levels of leptin and vitamin D. Almost 50% of the patients had increased osteoprotegerin levels after 3 years. Conclusion: A normal BMD does not exclude mineral bone disorder in patients with CKD, yet the BMD Z-scores were well preserved and most markers of bone turnover were within the reference intervals. [source] Bone mineral density in hyperthyroidismCLINICAL ENDOCRINOLOGY, Issue 4 2004Helen Karga Summary objective, To investigate whether previous hyperthyroidism is a cause of permanent secondary osteoporosis. design and patients, In this cross-sectional study, 164 women with untreated or previously treated overt and symptomatic hyperthyroidism were examined 0,31 years after the initial episode of hyperthyroidism and its treatment, and were compared with a control group of 79 age-matched women without previous history of hyperthyroidism. Subjects with current or previous metabolic bone disease, any antiresorptive treatment for osteoporosis or treatments and habits known to affect bone metabolism were excluded. measurements, The age of the first manifestation of the disease, the age at the measurement of bone mineral density (BMD) at the spine and femoral neck and the interval between diagnosis and treatment of hyperthyroidism and BMD measurement were recorded and the Z-scores and T-scores of BMD were analysed. results, Untreated hyperthyroidism and hyperthyroidism up to 3 years after its diagnosis and treatment were associated with decreased BMD. Three or more years after the first episode of the disease the mean Z-score at both skeletal sites was near zero and not different from the controls. The age at which hyperthyroidism was manifested for the first time had no effect on the final outcome. Women affected at a young age (13,30 years) had a more pronounced loss of BMD when examined untreated or early (< 3 years) after diagnosis, but a BMD significantly above zero if examined later (> 3 years). Older women (aged 51,70 years) showed a similar pattern, although the differences were not significant. Middle-aged subjects (31,50 years) had the smallest loss of BMD during the first 3 years. Analysis of T-scores of former hyperthyroid women aged , 51 years showed no significantly different relative risk (RR) for osteoporosis in comparison with the controls. However, the study was not powered enough to give meaningful RR results. conclusions, Overt symptomatic hyperthyroidism is associated with decreased BMD during the first 3 years after diagnosis and treatment of the disease. After this interval, former hyperthyroid women have a Z-score near zero and not different from women without a history of the disease, apparently because of recovery of the bone density lost early during the course of the disease. Symptomatic hyperthyroidism does not seem to be a cause of long-lasting osteoporosis, and the age of the patient during the first episode is irrelevant. [source] Subfield atrophy pattern in temporal lobe epilepsy with and without mesial sclerosis detected by high-resolution MRI at 4 Tesla: Preliminary resultsEPILEPSIA, Issue 6 2009Susanne G. Mueller Summary Purpose:, High-resolution magnetic resonance imaging (MRI) at 4 Tesla depicts details of the internal structure of the hippocampus not visible at 1.5 Tesla, and so allows for in vivo parcellation of different hippocampal subfields. The aim of this study was to test if distinct subfield atrophy patterns can be detected in temporal lobe epilepsy (TLE) with mesial temporal sclerosis (TLE-MTS) and without (TLE-no) hippocampal sclerosis. Methods:, High-resolution T2 -weighted hippocampal images were acquired in 34 controls: 15 TLE-MTS and 18 TLE-no. Entorhinal cortex (ERC), subiculum (SUB), CA1, CA2, and CA3, and dentate (CA3&DG) volumes were determined using a manual parcellation scheme. Results:, TLE-MTS had significantly smaller ipsilateral CA1, CA2, CA3&DG, and total hippocampal volume than controls or TLE-no. Mean ipsilateral CA1 and CA3&DG z-scores were significantly lower than ipsilateral CA2, ERC, and SUB z-scores. There were no significant differences between the various subfield or hippocampal z-scores on either the ipsi- or the contralateral side in TLE-no. Using a z-score ,,2.0 to identify severe volume loss, the following atrophy patterns were found in TLE-MTS: CA1 atrophy, CA3&DG atrophy, CA1 and CA3&DG atrophy, and global hippocampal atrophy. Significant subfield atrophy was found in three TLE-no: contralateral SUB atrophy, bilateral CA3&DG atrophy, and ipsilateral ERC and SUB atrophy. Discussion:, Using a manual parcellation scheme on 4 Tesla high-resolution MRI, we found the characteristic ipsilateral CA1 and CA3&DG atrophy described in TLE-MTS. Seventeen percent of the TLE-no had subfield atrophy despite normal total hippocampal volume. These findings indicate that high-resolution MRI and subfield volumetry provide superior information compared to standard hippocampal volumetry. [source] Intensity modulation of TMS-induced cortical excitation: Primary motor cortexHUMAN BRAIN MAPPING, Issue 6 2006Peter T. Fox Abstract The intensity dependence of the local and remote effects of transcranial magnetic stimulation (TMS) on human motor cortex was characterized using positron-emission tomography (PET) measurements of regional blood flow (BF) and concurrent electromyographic (EMG) measurements of the motor-evoked potential (MEP). Twelve normal volunteers were studied by applying 3 Hz TMS to the hand region of primary motor cortex (M1hand). Three stimulation intensities were used: 75%, 100%, and 125% of the motor threshold (MT). MEP amplitude increased nonlinearly with increasing stimulus intensity. The rate of rise in MEP amplitude was greater above MT than below. The hemodynamic response in M1hand was an increase in BF. Hemodynamic variables quantified for M1hand included value-normalized counts (VNC), intensity (z-score), and extent (mm3). All three hemodynamic response variables increased nonlinearly with stimulus intensity, closely mirroring the MEP intensity-response function. VNC was the hemodynamic response variable which showed the most significant effect of TMS intensity. VNC correlated strongly with MEP amplitude, both within and between subjects. Remote regions showed varying patterns of intensity response, which we interpret as reflecting varying levels of neuronal excitability and/or functional coupling in the conditions studied. Hum Brain Mapp, 2005. © 2005 Wiley-Liss, Inc. [source] Y-position cysteine substitution in type I collagen (,1(I) R888C/p.R1066C) is associated with osteogenesis imperfecta/Ehlers-Danlos syndrome phenotype,,HUMAN MUTATION, Issue 4 2007Wayne A. Cabral Abstract The most common mutations in type I collagen causing types II,IV osteogenesis imperfecta (OI) result in substitution for glycine in a Gly-Xaa-Yaa triplet by another amino acid. We delineated a Y-position substitution in a small pedigree with a combined OI/Ehlers-Danlos Syndrome (EDS) phenotype, characterized by moderately decreased DEXA z-score (,1.3 to ,2.6), long bone fractures, and large-joint hyperextensibility. Affected individuals have an ,1(I)R888C (p.R1066C) substitution in one COL1A1 allele. Polyacrylamide gel electrophoresis (PAGE) of [3H]-proline labeled steady-state collagen reveals slight overmodification of the ,1(I) monomer band, much less than expected for a substitution of a neighboring glycine residue, and a faint ,1(I) dimer. Dimers form in about 10% of proband type I collagen. Dimer formation is inefficient compared to a possible 25%, probably because the SH-side chains have less proximity in this Y-position than when substituting for a glycine. Theoretical stability calculations, differential scanning calorimetry (DSC) thermograms, and thermal denaturation curves showed only weak local destabilization from the Y-position substitution in one or two chains of a collagen helix, but greater destabilization is seen in collagen containing dimers. Y-position collagen dimers cause kinking of the helix, resulting in a register shift that is propagated the full length of the helix and causes resistance to procollagen processing by N-proteinase. Collagen containing the Y-position substitution is incorporated into matrix deposited in culture, including immaturely and maturely cross-linked fractions. In vivo, proband dermal fibrils have decreased density and increased diameter compared to controls, with occasional aggregate formation. This report on Y-position substitutions in type I collagen extends the range of phenotypes caused by nonglycine substitutions and shows that, similar to X- and Y-position substitutions in types II and III collagen, the phenotypes resulting from nonglycine substitutions in type I collagen are distinct from those caused by glycine substitutions. Hum Mutat 28(4), 396,405, 2007. Published 2007 Wiley-Liss, Inc. [source] Treatment of Idiopathic Hyperphosphatasia With Intensive Bisphosphonate TherapyJOURNAL OF BONE AND MINERAL RESEARCH, Issue 5 2004Tim Cundy MD Abstract In a family with IH, a rare high turnover bone disease, two older siblings were wheelchair-bound with severe skeletal deformity by age 15. Their youngest affected sibling was treated intensively with intravenous bisphosphonates for 3 years. The treatment was well tolerated and prevented the development of deformity and disability. Introduction: Idiopathic hyperphosphatasia (IH, also known as juvenile Paget's disease) is a rare genetic bone disease characterized by very high bone turnover and progressive bony deformity. Inhibitors of bone resorption have been used to suppress bone turnover in the short term, but there is no published data on long-term efficacy. Materials and Methods: An 11-year-old girl with IH, who had two severely affected older siblings, presented with progressive deformity and deafness and long bone fractures. Conventional pediatric doses of pamidronate had failed to prevent clinical deterioration or suppress bone turnover completely. Intensive bisphosphonate therapy (frequent 5-mg ibandronate infusions) was given to try and arrest progression of the skeletal disease. Growth and development, pure tone audiometry, biochemistry, radiology, densitometry (DXA), and bone histology were monitored. Results: A total of 45 mg ibandronate was given over 3 years until skeletal maturity was reached (20, 15, and 10 mg for years 1,3, respectively). Ibandronate treatment was well tolerated, and biochemical markers of bone turnover suppressed to within the age-appropriate normal range There was some progression of her thoracic kyphosis, but she had no further fractures and remained mobile and active at an age when her siblings had become wheelchair-bound. A significant recovery of hearing (p < 0.01) was documented, particularly at low frequencies. Radiographs showed improvement in spinal osteoporosis and cortical bone dimensions and arrest of progressive acetabular protrusion. Areal bone density increased substantially (lumbar spine z-score from ,2.2 to + 1.8). Tetracycline-labeled bone biopsy specimens were taken before and after 18 months of intensive treatment. The second biopsy showed suppression of bone turnover and a doubling of trabecular thickness, with no mineralization defect, and no osteopetrosis. Conclusions: Intensive bisphosphonate treatment prevented the development of deformity and disability and improved hearing in this child with IH. The dose of bisphosphonate, which is substantially greater than is usually used in pediatric bone disease, had no adverse effects, in particular on bone mineralization. [source] Positive Linear Growth and Bone Responses to Growth Hormone Treatment in Children With Types III and IV Osteogenesis Imperfecta: High Predictive Value of the Carboxyterminal Propeptide of Type I Procollagen,JOURNAL OF BONE AND MINERAL RESEARCH, Issue 2 2003Joan C Marini MD Abstract Extreme short stature is a cardinal feature of severe osteogenesis imperfecta (OI), types III and IV. We conducted a treatment trial of growth hormone in children with OI and followed linear growth velocity, bone metabolism markers, histomorphometrics, and vertebral bone density. Twenty-six children with types III and IV OI, ages 4.5,12 years, were treated with recombinant growth hormone (rGH), 0.1,0.2 IU/kg per day for 6 days/week, for at least 1 year. Length, insulin-like growth factor (IGF-I), insulin-like growth factor binding protein (IGFBP-3), bone metabolic markers, and vertebral bone density by DXA were evaluated at 6-month intervals. An iliac crest biopsy was obtained at baseline and 12 months. Approximately one-half of the treated OI children sustained a 50% or more increase in linear growth over their baseline growth rate. Most responders (10 of 14) had moderate type IV OI. All participants had positive IGF-I, IGFBP-3, osteocalcin, and bone-specific alkaline phosphatase responses. Only the linear growth responders had a significant increase in vertebral DXA z-score and a significant decrease in long bone fractures. After 1 year of treatment, responders' iliac crest biopsy showed significant increases in cancellous bone volume, trabecular number, and bone formation rate. Responders were distinguished from nonresponders by higher baseline carboxyterminal propeptide (PICP) values (p < 0.05), suggesting they have an intrinsically higher capacity for collagen production. The results show that growth hormone can cause a sustained increase in the linear growth rate of children with OI, despite the abnormal collagen in their bone matrix. In the first year of treatment, growth responders achieve increased bone formation rate and density, and decreased fracture rates. The baseline plasma concentration of PICP was an excellent predictor of positive response. [source] Infant weight-for-length is positively associated with subsequent linear growth across four different populationsMATERNAL & CHILD NUTRITION, Issue 1 2005Kathryn G. Dewey phd Abstract Several studies have documented that length gain often lags behind weight gain during infancy and early childhood, suggesting that linear growth is partly regulated by initial body mass or fatness. To investigate this hypothesis, we analysed data from four longitudinal studies on growth of infants in the first 12 months: (1) U.S. breast-fed and formula-fed infants (n = 89); (2) breast-fed infants in Ghana (n = 190); (3) normal birthweight, breast-fed infants in Honduras (n = 108); and (4) term, low-birthweight breast-fed infants in Honduras (n = 119). The dependent variable was length gain during each 3-month interval (1, 4, 2,5, 3,6, 4,7, 5,8, 6,9, 7,10, 8,11 and 9,12 months). Three main independent variables were examined: initial weight-for-length z-score (W/L), weight change during the prior 3 months, and initial skinfold thickness. Controlling for maternal height, infant sex, and initial length-for-age z-score, length gain was positively correlated with initial W/L and prior weight change during all age intervals and with initial skinfold thickness at 3 and 4 months (r = 0.15,0.36; P < 0.01). There was no evidence of a threshold effect. These associations were evident in all four populations, in both boys and girls, and in breast-fed and formula-fed infants. The consistency of this relationship across studies supports the hypothesis that linear growth is partly regulated by initial body mass or fatness in infants. [source] Antenatal and postpartum depressive symptoms are differentially associated with early childhood weight and adiposityPAEDIATRIC & PERINATAL EPIDEMIOLOGY, Issue 2 2010Karen A. Ertel Summary Ertel KA, Koenen KC, Rich-Edwards JW, Gillman MW. Antenatal and postpartum depressive symptoms are differentially associated with early childhood weight and adiposity. Paediatric and Perinatal Epidemiology 2010; 24: 179,189. Antenatal depression is associated with small-for-gestational age, but few studies have examined associations with weight during childhood. Similarly, few studies address whether antenatal and postpartum depression differentially affect child weight. Among 838 mother,child dyads in Project Viva, a prospective cohort study, we examined relationships of antenatal and postpartum depression with child weight and adiposity. We assessed maternal depression at mid-pregnancy and 6 months postpartum with the Edinburgh Postnatal Depression Scale (score ,13 indicating probable depression). We assessed child outcomes at age 3 years: body mass index (BMI) z-score, weight-for-height z-score, sum of subscapular (SS) and triceps (TR) skinfold thickness (SS + TR) for overall adiposity, and SS : TR ratio for central adiposity. Sixty-nine (8.2%) women experienced antenatal depression and 59 (7.0%) postpartum depression. Mean (SD) outcomes at age 3 were: BMI z-score, 0.45 (1.01); SS + TR, 16.72 (4.03) mm; SS : TR, 0.64 (0.15). In multivariable models, antenatal depression was associated with lower child BMI z-score (,0.24 [95% confidence interval: ,0.49, 0.00]), but higher SS : TR (0.05 [0.01, 0.09]). There was no evidence of a dose,response relationship between antenatal depression and these outcomes. Postpartum depression was associated with higher SS + TR (1.14 [0.11, 2.18]). In conclusion, whereas antenatal depression was associated with smaller size and central adiposity at age 3 years, postpartum depression was associated with higher overall adiposity. [source] Obesity dynamics and cardiovascular risk factor stability in obese adolescentsPEDIATRIC DIABETES, Issue 6 2009Ram Weiss Aim:, Cross-sectional studies showed worsening of cardiovascular risk factors with increasing severity of childhood obesity. The aim of this study was to investigate the impact of obesity dynamics on cardiovascular risk factors and on the stability of the diagnosis of metabolic syndrome (MS) in obese youth. Methods and results:, A longitudinal assessment of components of the MS using two definitions was performed in 186 obese adolescents (106 females/80 males, age 13.1 ± 2.5 yr). Components of the MS were assessed at baseline and after 19 ± 7 months. We stratified the cohort into three categories based on the 25th and 75th percentile of body mass index (BMI) z-score change: category 1 reduced BMI z-score by 0.09 or more, category 2 had a BMI z-score change of between ,0.09 and 0.12, and category 3 increased BMI z-score by >0.12. Subjects who reduced their BMI z-score significantly decreased their fasting and 2-h glucose levels and triglyceride levels and increased their high density lipoprotein cholesterol in comparison to subjects who increased their BMI z-score. BMI z-score changes negatively correlated with changes in insulin sensitivity (r = ,0.36, p < 0.001). Among those with no MS at baseline (n = 119), 10 (8%), most of whom significantly increased their BMI z-score, developed MS. Of 67 who had MS at baseline, 33 (50%), most of whom decreased their BMI z-score, lost the diagnosis. Conclusions:, Obesity dynamics, tightly linked to changes in insulin sensitivity, have an impact on each individual component of the MS and on the stability of the diagnosis of MS in obese youth. [source] One-year glargine treatment can improve the course of lung disease in children and adolescents with cystic fibrosis and early glucose derangementsPEDIATRIC DIABETES, Issue 3 2009Enza Mozzillo Background:, Diabetes increases morbidity and mortality in cystic fibrosis (CF) patients, but several studies indicate that also prediabetic status may have a potential impact on both nutrition and lung function. Objective:, To evaluate the effect of glargine on the clinical course in CF patients with early glucose derangements. Methods:, CF population was screened for glucose tolerance. CF patients with age >10 yr were screened with fasting hyperglycemia (FH). CF patients with age >10 yr without FH and those with age <10 yr with occasional FH were evaluated for glucose abnormalities on the basis of oral glucose tolerance test and/or continuous glucose monitoring system. All CF patients with glucose derangements were enrolled in an open clinical trial with glargine. Body mass index (BMI) z-score, forced expiratory volume in the first second (FEV1), number of acute pulmonary exacerbations and hemoglobin A1c, were as outcome measures at baseline and after 1 yr of treatment. Results:, After 12 months of therapy, BMI z-score improved only in patients with baseline BMI z-score less than ,1 (p = 0.017). An 8.8% increase in FEV1 (p = 0.01) and 42% decrease in the number of pulmonary exacerbations (p = 0.003) were found in the whole group compared with previous 12 months of therapy. Conclusion:, Glargine could represent an innovative strategy to prevent lung disease progression in CF patients with early glucose derangements. Larger controlled trials are needed to better clarify the effects of insulin on clinical status in CF patients with early glucose derangements. [source] Zoledronic acid for the treatment of osteopenia in pediatric Crohn's diseasePEDIATRICS INTERNATIONAL, Issue 5 2010Anne Marie Sbrocchi Abstract Background:, Pediatric patients with Crohn's disease often have low bone mass (osteopenia) for age. No randomized, placebo-controlled trials using zoledronic acid have ever been performed in this population. The objective of this study was to assess the efficacy of zoledronic acid in children with Crohn's disease and osteopenia. Methods:, A double-blind, randomized, placebo-controlled design was used. Thirteen adolescents received either a single intravenous dose of zoledronic acid (0.066 mg/kg, max 4 mg, n= 7) or saline placebo (n= 6). The primary outcome was change in lumbar spine bone mineral density (LSBMD) z-score at 6 months. Secondary outcomes included bone markers and adverse events. Results:, At 6 months, the change in LSBMD z-score was significantly higher in the zoledronic acid group compared to placebo (0.7 vs 0.1, P < 0.001). Volumetrically adjusted LSBMD z-score also significantly increased in the treated group. This significant difference persisted until 12 months. With zoledronic acid, urinary C-telopeptide excretion decreased by 50% at 6 months and remained suppressed at 12 months (P= 0.02), but no changes were observed with placebo. Both groups had similar adverse events which included transient fever, arthralgias, and nausea (3/7 treated, 2/6 placebo, P= NS). Conclusions:, In this study, zoledronic acid demonstrated a significant increase in LSBMD at 6 and 12 months following a well-tolerated infusion. [source] Not Another Formula for Heart Rate Correction of QT IntervalANNALS OF NONINVASIVE ELECTROCARDIOLOGY, Issue 1 2009F.R.C.P., Peter J. Bourdillon M.B.B.S. Background: Normal limits for QT and heart rate were developed in a Japanese population undergoing 24 hour recordings of the electrocardiogram (ECG). The purpose of this study is to validate these normal limits in a West London population having 12-lead ECGs. Methods: A retrospective observational cohort of 10,099 patients aged 20,79 attending a hospital ECG department was studied. From the Japanese data z-scores were calculated for men under 50, for men over 50, for women under 50 and for women over 50. z-scores were used to compare the West London and Japanese populations. Results: Cardiac infarction injury scores (CIIS) for all four groups were less than zero indicating a population at low risk of cardiovascular disease. From the Japanese data a z-score of 1 is roughly 20 ms. West London mean (SD) z-scores for men under 50, for men over 50, for women under 50 and for women over 50 were 0.20 (0.85), ,0.02 (0.86), 0.14 (0.93), and ,0.45 (0.88), respectively. Conclusions: The distributions of the QT and heart rate data of a West London population at low risk of cardiovascular disease are comparable to the Japanese data. The Japanese QT normal limits for women over the age of 50 are about 9 ms higher regardless of heart rate. The QT normal limits for Afro-Caribbeans are about 5 ms lower than other ethnic groups. The Japanese normal limits are applicable elsewhere, albeit adjusting for women over the age of 50 and for Afro-Caribbeans. [source] Factors associated with successful establishment of breastfeeding in very preterm infantsACTA PAEDIATRICA, Issue 7 2010G Zachariassen Abstract Aim:, To describe feeding practices at hospital discharge in relation to characteristics of the very preterm infants (VPI) and their mothers. Methods:,Design. Prospective hospital-based registration of very preterm infants born with a gestational age ,32 weeks in Denmark during 2004,2008. Subjects. Healthy mothers and VPI without diseases causing eating disabilities at discharge. Results:, A total of 478 VPI were registered. At discharge, 60% were exclusively breastfed, 35% were exclusively bottlefed, and 5% were both breast- and bottle-fed. Mothers of high social class (p = 0.000) and ,not smoking' (p = 0.003) were significantly more often breastfeeding their preterm infant(s) at discharge. Single births infants tended more often to be breastfed (p = 0.09). Infant age at discharge and duration of hospitalization did not influence breastfeeding at discharge. Increase in weight z-score from birth to discharge was largest in the bottlefeeding-group compared with the breastfeeding-group (p = 0.000) probably as a result of feeding practice the last week(s) of hospitalization. Conclusion:, Breastfeeding can successfully be established in very preterm infants. Mothers of low social classes, smokers, multiple birth and very preterm infants with low weight for age may need extra attention in breastfeeding establishing policies. [source] First year growth among very low birth weight infantsACTA PAEDIATRICA, Issue 4 2010Ane C. Westerberg Abstract Aim:, The aim of this study was to describe first-year growth among very low birth weight infants and the effect of growth restriction at hospital discharge on first year growth. Method:, Anthropometric measures and background information for 118 very low birth weight infants were collected from medical records. Z-scores were calculated based on recent Norwegian growth references. Results:, Significant catch-up growth for weight and length was observed during the first year with mean z-score change (SD) of 0.40 (1.05) and 1.01 (1.25) respectively. However, the very low birth weight infants remained lighter and shorter than full-term peers until 12 months corrected age with mean z-score of ,0.93 (1.09) and ,0.48 (1.06) respectively. Head circumference followed a normal growth pattern after 2 months. Infants discharged from hospital as growth restricted had increased catch-up in weight and length, but remained smaller than infants not subjected to early growth restriction and full-term peers. Multiple regression showed that weight below the 10th percentile at discharge is important for weight and length during the first year of life. Conclusion:, Very low birth weight infants showed catch-up growth during the first year, but their weight and length remained less than full-term peers. Growth deficiencies were more pronounced among infants subjected to early growth restriction, despite increased catch-up growth. [source] Long-term effects of rapid weight gain in children, adolescents and young adults with appropriate birth weight for gestational age: the kiel obesity prevention studyACTA PAEDIATRICA, Issue 2 2010B Hitze Abstract Aim:, This study investigates the effect of rapid weight gain in term children, adolescents and young adults born appropriate for gestational age. Methods:, In all, 173 girls and 178 boys aged 6.1,19.9 (12.5 ± 3.1)years participated. Rapid weight gain (group 1) was defined as a change in weight-SDS (standard deviation score) from birth till two years >0.67, ,no change' as ,,0.67 and ,0.67 (group 2) vs ,slow weight gain' as <,0.67 (group 3). BMI-SDS, waist circumference (WC) z-score, fat mass (FM)/fat free mass (FFM; Air-Displacement-Plethysmography), resting energy expenditure (REE; ventilated hood system), cardio-metabolic risk factors, serum leptin and adiponectin were assessed. >90th age-/sex-specific BMI-percentile was defined as overweight. Parental BMI, socio-economic status and lifestyle were assessed as confounders. Results:, A total of 22.8% gained weight rapidly, and 15.7% was overweight. Group 1 compared with group 2 and 3 subjects was taller, heavier and had a higher prevalence of overweight (girls/boys: 26.2%/28.9% vs 11.6%/19.0% vs 2.8%/5.0%; p < 0.01/p < 0.05). Concomitantly, a higher WC, %FM and FFM were observed. Rapid weight gain was positively associated with REE (adjusted for FFM) in boys (r = 0.26; p < 0.01), but not with cardio-metabolic risk factors. Conclusion:, Rapid weight gain was related to increases in height, weight, a higher prevalence of overweight and central fat distribution. In addition, rapid weight gain was related to a higher REE in boys, but not to cardio-metabolic risk factors. [source] | ||||||||||||||||||||||||||||||||||