Aim: To determine the prevalence of renal anomalies in patients with an isolated single umbilical artery (SUA). Methods: We performed a retrospective study of all renal ultrasound examinations... Show moreAim: To determine the prevalence of renal anomalies in patients with an isolated single umbilical artery (SUA). Methods: We performed a retrospective study of all renal ultrasound examinations assessed at our centre between January 1998 and December 2008 in neonates with SUA with or without associated anomalies. Results: Renal ultrasound examination was performed in 65 neonates with SUA (57 neonates with isolated SUA and 8 neonates with nonisolated SUA). The prevalence of renal anomalies in the group with and without isolated SUA was 2% (1/57) and 38% (3/8), respectively. Only one patient with isolated SUA had a mild renal abnormality without clinical consequences. Conclusions: The prevalence of renal anomalies in neonates with isolated SUA is low. We suggest that routine ultrasound screening for renal anomalies is not warranted in neonates with isolated SUA. Copyright (C) 2009 S. Karger AG, Basel Show less
Velamentous cord insertion and vasa previa occur more frequently in monochorionic twin pregnancies than in singleton pregnancies. Both have been linked with poor perinatal outcome due to the... Show moreVelamentous cord insertion and vasa previa occur more frequently in monochorionic twin pregnancies than in singleton pregnancies. Both have been linked with poor perinatal outcome due to the increased risk of rupture of the velamentous vessels. We present a case of acute fetal distress in 2 fetuses in a monochorionic twin pregnancy caused by ruptured vasa previa that was not detected antenatally. Both infants were severely anemic at birth. Acute blood loss in twin 1 through the ruptured vessels, led to an acute feto-fetal transfusion from the co-twin through the placental vascular anastomoses. In monochorionic twins, ruptured vasa previa and acute hemorrhage in one fetus can lead to acute feto-fetal transfusion and result in severe hypovolemic shock and acute anemia in both fetuses. Increased awareness for vasa previa and the characteristic placental angioarchitecture in monochorionic twinning is of paramount importance. Copyright (C) 2010 S. Karger AG, Basel Show less
Background: Respiratory distress syndrome (RDS) is currently treated with surfactant preparations obtained from natural sources and attempts to develop equally active synthetic surfactants have... Show moreBackground: Respiratory distress syndrome (RDS) is currently treated with surfactant preparations obtained from natural sources and attempts to develop equally active synthetic surfactants have been unsuccessful. One difference in composition is that naturally derived surfactants contain the two hydrophobic proteins SP-B and SP-C while synthetic preparations contain analogues of either SP-B or SP-C. It was recently shown that both SP-B and SP-C (or SP-C33, an SP-C analogue) are necessary to establish alveolar stability at end-expiration in a rabbit RDS model, as reflected by high lung gas volumes without application of positive end-expiratory pressure. Objectives: To study the efficacy of fully synthetic surfactants containing analogues of both SP-B and SP-C compared to surfactants with only one protein analogue. Methods: Premature newborn rabbits, treated with synthetic surfactants, were ventilated for 30 min without positive end-expiratory pressure. Tidal volumes as well as lung gas volumes at end-expiration were determined. Results: Treatment with 2% Mini-B (a short-cut version of SP-B) and 2% SP-C33, or its C-terminally truncated form SP-C30, in 1,2-dipalmitoyl-sn-glycero-3-phosphocholine/1-palmitoyl-2-oleoyl-sn-glycero-3-phosphoglycerol, 68: 31 (w/w) resulted in median lung gas volumes of 8-9 ml/kg body weight, while animals treated with 2% Mini-B surfactant or 2% SPC33/SP-C30 surfactant had lung gas volumes of 3-4 ml/kg, and those treated with Curosurf, a porcine surfactant, 15-17 ml/kg. In contrast, mixing SP-C33 with peptides with different distributions of positively charged and hydrophobic residues did not improve lung gas volumes. Conclusions: The data indicate that synthetic surfactants containing analogues of both SP-B and SP-C might be superior to single-peptide surfactants in the treatment of RDS. Copyright (C) 2010 S. Karger AG, Basel Show less
Background The birth prevalence of severe haemoglobinopathies such as sickle cell disease (SCD) in the Netherlands has been estimated to be at least 50 newborns per year. Neonatal screening for SCD... Show moreBackground The birth prevalence of severe haemoglobinopathies such as sickle cell disease (SCD) in the Netherlands has been estimated to be at least 50 newborns per year. Neonatal screening for SCD was added to the Dutch screening programme in January 2007. We here evaluated three high performance liquid chromatography (HPLC) systems for application in neonatal screening for haemoglobinopathies, and present the results of a subsequent pilot screening programme. Methods The Variant New Born Screening (Vnbs) HPLC system (Bio-Rad) was validated by analysing 131 blood samples and blood mixtures. Subsequently, the performance of the G7 (Tosoh BioScience) and Ultra (Primus Corporation) was compared with the Vnbs. The three HPLC analysers were tested in a pilot screening programme on 21,969 dried blood spot samples from the routine Dutch neonatal screening programme. Results The pilot screening resulted in 188 abnormal patterns. The three HPLC devices presented comparable within- and between-run precision and detected the abnormal samples similarly. The high throughput, sampling systems, presentation of results, and integration of the chromatograms, however, were different. Conclusion All three analysers detected the same abnormal haemoglobins satisfactorily, but integrated the chromatograms with variable imprecision. Comparison of the results suggested that the Bio-Rad Vnbs was the preferred system. However, software adjustments were required to improve the diagnostic potential of this device for screening for beta- and alpha-thalassaemia. Show less
Miclea, R.L.; Karperien, M.; Langers, A.M.; Robanus Maandag, E.C.; Lierop, A. van; Hiel, B. van der; ... ; Hamdy, N.A. 2010
The canonical Wnt pathway plays a key regulatory role in osteoblastogenesis and bone mass acquisition through its main effector, beta-catenin Adenomatous polyposis coli (APC) represents the key... Show moreThe canonical Wnt pathway plays a key regulatory role in osteoblastogenesis and bone mass acquisition through its main effector, beta-catenin Adenomatous polyposis coli (APC) represents the key intracellular gatekeeper of beta-catenin turnover, and heterozygous germline mutations in the APC gene cause familial adenomatous polyposis (FAP) Whether APC mutations affect bone mass has not been previously investigated We conducted a cross-sectional study evaluating skeletal status in FAP patients with a documented APC mutation Twenty-two FAP patients with a mean age of 42 years (545% women) were included in this study Mean bone mineral density (BMD) Z-scores were significantly increased above normal at all measured sites lumbar spine (p < 01), total hip (p < 01), femoral neck (p < 05), and trochanter (p < 01) Z-scores were +1 or greater in 14 patients (63 6%) and +2 or greater in 5 (22 7%) Mean values of bone turnover markers were within normal ranges There was a significant positive correlation between procollagen type I N-terminal propeptide (P1NP) and beta-crosslaps (beta-CTX) (r = 0 70, p < 001) and between these markers and sclerostin and BMD measurements We demonstrate that FAP patients display a significantly higher than normal mean BMD compared with age- and sex-matched healthy controls in the presence of a balanced bone turnover Our data suggest a state of "controlled" activation of the Wnt signaling pathway in heterozygous carriers of APC mutations, most likely owing to upregulation of cytoplasmic beta-catenin levels (C) 2010 American Society for Bone and Mineral Research Show less
Molen, M.J.W. van der; Huizinga, M.; Huizenga, H.M.; Ridderinkhof, K.R.; Hamel, B.J.; Curfs, L.M.; Ramakers, G.J. 2010
The present study examined the cognitive profile in Fragile X Syndrome (FXS) males, and investigated whether cognitive profiles are similar for FXS males at different levels of intellectual... Show moreThe present study examined the cognitive profile in Fragile X Syndrome (FXS) males, and investigated whether cognitive profiles are similar for FXS males at different levels of intellectual functioning. Cognitive abilities in non-verbal, verbal, memory and executive functioning domains were contrasted to both a non-verbal and verbal mental age reference. Model-based cluster analyses revealed three distinct subgroups which differed in level of functioning, but showed similar cognitive profiles. Results showed that cognitive performance is particularly weak on measures of reasoning- and performal abilities confined to abstract item content, but relatively strong on measures of visuo-perceptual recognition and vocabulary. Further, a significant weakness was found for verbal short-term memory. Finally, these results indicated that the choice of an appropriate reference is critically important in examining cognitive profiles. The pattern of findings that emerged from the current cognitive profiling of FXS males was interpreted to suggest a fundamental deficit in executive control. Show less
Gorter, D.J.J. de; Dinther, M. van; Dijke, P. ten; Conn, P.M. 2010
Bone morphogenetic proteins (BMPs) are pleiotropic cytokines controlling a multitude of processes, among which bone formation. BMPs function by binding and activating BMP type I and type II... Show moreBone morphogenetic proteins (BMPs) are pleiotropic cytokines controlling a multitude of processes, among which bone formation. BMPs function by binding and activating BMP type I and type II receptors, resulting in activation of Smad transcription factors and expression of BMP target genes. Mutations in the BMP type I receptor ALK2 were identified in patients suffering from Fibrodysplasia Ossificans Progressiva (FOP). The mutation found in all patients displaying classical FOP symptoms, the ALK2 R206H mutation, renders ALK2 constitutively active. Here, we provide a detailed description of how to determine whether other ALK2 mutations will confer constitutive activity to the receptor. Show less
Background: Preconception carrier screening for hemoglobinopathies (HbPs) is debated in the Netherlands. Objectives: Intentions to participate in preconception carrier screening for HbPs as well as... Show moreBackground: Preconception carrier screening for hemoglobinopathies (HbPs) is debated in the Netherlands. Objectives: Intentions to participate in preconception carrier screening for HbPs as well as informed reproductive options were assessed in 109 Turkish female immigrants. Method: Participants completed a structured questionnaire. Results: 83.5% of 109 Turkish female immigrants intended to participate in preconception carrier screening. Intention to participate was related to the desire to reduce uncertainty about having offspring affected by HbPs, but not with socio-demographic variables, risk-estimation and worrying. If the tests concerning carrier status for HbPs were confirmative for both partners, 36.3% (n = 33) of the women with the intention of preconception carrier screening would refrain from getting children of their own, including 14.3% (n = 13) opting for adoption, 37.4% (n = 34) would decide to become pregnant and to opt for prenatal testing on HbPs. Finally, among 37.4% of the women opting for prenatal testing, 30.3% (n = 10) would terminate an affected pregnancy, 18.2% (n = 6) not and 51.5% (n = 17) could not decide (1 missing value). Conclusion: A large majority of Turkish female immigrants would participate in preconception carrier screening for HbPs. Copyright (C) 2010 S. Karger AG, Basel Show less
Phylipsen, M.; Harteveld, C.L.; Metz, M. de; Gallivan, M.V.E.; Arkesteijn, S.G.J.; Luo, H.Y.; ... ; Giordano, P.C. 2010
We report a novel thalassemia determinant found in a Nigerian woman living in the Netherlands, resulting from a 2 bp insertion at codons 9/10 of the beta-globin gene (HBBc.28_29ins TA p.... Show moreWe report a novel thalassemia determinant found in a Nigerian woman living in the Netherlands, resulting from a 2 bp insertion at codons 9/10 of the beta-globin gene (HBBc.28_29ins TA p. Ser10LeufsX11). The novel defect causes a frameshift with a consequent premature TGA stop codon, located at 11 positions downstream from the mutated codon. The phenotype was typical of a beta-thalassemia (beta-thal), trait with high RBC counts and compensated mild microcytic anemia. However, the Hb A(2) level was reported to be normal due to the presence of the common Hb A(2)' or Hb B2 [delta 16(A13)Gly-->Arg, GGC>CGC] variant that was not taken into account. We also present the opposite but comparable situation found in an a Palestinian man living in the USA. He was a carrier of a common beta-globin gene defect [codon 6 (-A), HBB:c.20delA] in combination with a novel delta-globin gene defect at codon 6 [HBD.c.19G>C, Glu6Gln] that we have named Hb A(2)-Ramallah. In both cases, the provisional diagnosis could have been compromised when based on the measurement of the normal Hb A(2) fraction only. Show less
Zhang, S.; Sighem, A. van; Gras, L.; Reiss, P.; Smit, C.; Kroon, F.; ... ; Wolf, F. de 2010
Background: Transient episodes of HIV type-1 viraemia are frequently observed in patients on suppressive combination antiretroviral therapy (cART). We studied the effect of such episodes and of... Show moreBackground: Transient episodes of HIV type-1 viraemia are frequently observed in patients on suppressive combination antiretroviral therapy (cART). We studied the effect of such episodes and of treatment interruptions on clinical outcome and immunological response. Methods: A total of 3,321 patients from the ATHENA cohort had virological suppression (HIV type-1 RNA<50 copies/ml) after 24 weeks of cART. The association between subsequent episodes of treatment interruptions, viral suppression, low-level (50-400 copies/ml) and high-level (>400 copies/ml) viraemia and the outcomes death, AIDS or immunological response (CD4(+) T-cell count increase >= 50% from 24 weeks) was studied with Poisson regression models, including either time-updated cumulative follow-up, time spent per type of episode or modelling episodes as binary status indicators. Results: During 11,165 person-years of follow-up, 88 patients died, 111 developed AIDS and 2,019 had an immunological response. Longer follow-up time in treatment interruptions increased the risk of AIDS (relative risk [RR] 8.07, 95% confidence interval [CI] 3.98-16.4 per year longer) and impaired immunological response (RR 0.22, 95%) CI 0.12-0.41). High-level viraemia was only associated with immunological response (RR 0.55, 95% CI 0.40-0.74), whereas low-level viraemia was not associated with any of the three outcomes. Status indicator models gave similar results. When also including time-updated CD4(+) T-cell counts, the observed associations diminished. Conclusions: Treatment interruptions and high-level, but not low-level, viraemia are strongly associated with clinical outcome, mainly via their effect on CD4(+) T-cell counts Show less
Hilling, D.E.; Rijkelijkhuizen, J.K.; Marang-van de Mheen, P.J.; Tons, A.; Terpstra, O.T.; Bouwman, E. 2010
Background: A remarkable change in porcine islet morphology was observed after infusion of the pancreas with collagenase. The aim of the present study was to quantify these morphological changes... Show moreBackground: A remarkable change in porcine islet morphology was observed after infusion of the pancreas with collagenase. The aim of the present study was to quantify these morphological changes and to assess whether these changes were due to the volume expansion caused by the collagenase entering the islet or the result of its digestive effects. Methods: This study was performed in pancreata of 28 crossbred pigs. First, eight pancreata were intraductally injected with collagenase by a continuous controlled pressure of 180 mmHg. Pancreas samples before collagenase infusion were used as controls. All tissue samples, both before and after infusion, were stained with anti-insulin. To quantify the morphological change of the islets, the mean beta cell/endocrine content ratio of the infused and not-infused tissue samples was compared. In a second experiment, 20 pancreata were similarly assessed after intraductal injection with Hank's balanced salt solution (HBSS). Results: In both the collagenase- and HBSS-infused groups, mean beta cell/endocrine content ratio was lower than in the control samples. The observed decline in the beta cell/endocrine content ratio was not significantly different between collagenase- and HBSS-infused pancreata. This suggests that the lower beta cell/endocrine content ratio and thus the morphological change in the infused tissue samples is caused by volume expansion of the fluid entering the islet and that the digestive effect of collagenase plays no or only a minor role. Conclusion: Morphological changes of islets are observed after infusion of pancreata with collagenase and HBSS, most likely caused by volume expansion due to fluid entering the islets. Show less
Glucocorticoids are crucial in the initiation and consolidation of the stress response. Patients with active Cushing's syndrome (CS) are exposed to excessive endogenous glucocorticoid levels. In... Show moreGlucocorticoids are crucial in the initiation and consolidation of the stress response. Patients with active Cushing's syndrome (CS) are exposed to excessive endogenous glucocorticoid levels. In these patients, psychopathology is often being observed. The most common co-morbid disorder is major depression, but to a lesser extent mania and anxiety disorders have also been reported. A severe clinical presentation of CS often also includes depression. Reduction of glucocorticoid synthesis or action, either with metyrapone, ketoconazole, or mifepristone, rather than treatment with antidepressant drugs, is generally successful in relieving depressive symptoms, as well as other disabling symptoms. Following successful surgical treatment of hypercortisolism, both physical and psychiatric signs and symptoms improve substantially. However, it appears that patients do not completely return to their premorbid level of functioning and persistent impairment of quality of life and cognitive function has been reported despite long-term cure. At present, it is not clear whether, and to which extent, psychopathology still affects general well-being after long-term cure of CS. Copyright (C) 2010 S. Karger AG, Basel Show less
Background and aim Mesenchymal stromal cells (MSCs) are pluripotent cells that have immunosuppressive effects both in vitro and in experimental colitis. Promising results of MSC therapy have been... Show moreBackground and aim Mesenchymal stromal cells (MSCs) are pluripotent cells that have immunosuppressive effects both in vitro and in experimental colitis. Promising results of MSC therapy have been obtained in patients with severe graft versus host disease of the gut. Our objective was to determine the safety and feasibility of autologous bone marrow derived MSC therapy in patients with refractory Crohn's disease. Patients and intervention 10 adult patients with refractory Crohn's disease (eight females and two males) underwent bone marrow aspiration under local anaesthesia. Bone marrow MSCs were isolated and expanded ex vivo. MSCs were tested for phenotype and functionality in vitro. 9 patients received two doses of 1-2x10(6) cells/kg body weight, intravenously, 7 days apart. During follow-up, possible side effects and changes in patients' Crohn's disease activity index (CDAI) scores were monitored. Colonoscopies were performed at weeks 0 and 6, and mucosal inflammation was assessed by using the Crohn's disease endoscopic index of severity. Results MSCs isolated from patients with Crohn's disease showed similar morphology, phenotype and growth potential compared to MSCs from healthy donors. Importantly, immunomodulatory capacity was intact, as Crohn's disease MSCs significantly reduced peripheral blood mononuclear cell proliferation in vitro. MSC infusion was without side effects, besides a mild allergic reaction probably due to the cryopreservant DMSO in one patient. Baseline median CDAI was 326 (224-378). Three patients showed clinical response (CDAI decrease >= 70 from baseline) 6 weeks post-treatment; conversely three patients required surgery due to disease worsening. Conclusions Administration of autologous bone marrow derived MSCs appears safe and feasible in the treatment of refractory Crohn's disease. No serious adverse events were detected during bone marrow harvesting and administration. Show less
Background There is concern that non-inferiority trials might be deliberately designed to conceal that a new treatment is less effective than a standard treatment. In order to test this hypothesis... Show moreBackground There is concern that non-inferiority trials might be deliberately designed to conceal that a new treatment is less effective than a standard treatment. In order to test this hypothesis we performed a meta-analysis of non-inferiority trials to assess the average effect of experimental treatments compared with standard treatments. Methods One hundred and seventy non-inferiority treatment trials published in 121 core clinical journals were included. The trials were identified through a search of PubMed (1991 to 20 February 2009). Combined relative risk (RR) from meta-analysis comparing experimental with standard treatments was the main outcome measure. Results The 170 trials contributed a total of 175 independent comparisons of experimental with standard treatments. The combined RR for all 175 comparisons was 0.994 [95% confidence interval (CI) 0.978-1.010] using a random-effects model and 1.002 (95% CI 0.996-1.008) using a fixed-effects model. Of the 175 comparisons, experimental treatment was considered to be non-inferior in 130 (74%). The combined RR for these 130 comparisons was 0.995 (95% CI 0.983-1.006) and the point estimate favoured the experimental treatment in 58% (n = 76) and standard treatment in 42% (n = 54). The median non-inferiority margin (RR) pre-specified by trialists was 1.31 [inter-quartile range (IQR) 1.18-1.59]. Conclusion In this meta-analysis of non-inferiority trials the average RR comparing experimental with standard treatments was close to 1. The experimental treatments that gain a verdict of non-inferiority in published trials do not appear to be systematically less effective than the standard treatments. Importantly, publication bias and bias in the design and reporting of the studies cannot be ruled out and may have skewed the study results in favour of the experimental treatments. Further studies are required to examine the importance of such bias. Show less
Dekker, J.W.T.; Peeters, K.C.; Putter, H.; Vahrmeijer, A.L.; Velde, C.J.H. van de 2010
Aims: Optimal staging in rectal cancer is indispensable for the decision on further treatment and estimation of prognosis. This study assesses the prognostic capacity of the metastatic lymph node... Show moreAims: Optimal staging in rectal cancer is indispensable for the decision on further treatment and estimation of prognosis. This study assesses the prognostic capacity of the metastatic lymph node ratio (LNR) in addition to the new TNM classification. Methods: LNR was determined, in stage III patients from the Dutch TME-trial. Six year median follow up data from the trial database were used to analyse the relation of LNR to overall survival (OS) and local recurrence (LR). The relation of LNR to lymph node yield was assessed and appropriate cut off values of LNR for clinical use were determined. Results: 605 patients were analyzed. 278 underwent pre-operative radiotherapy. 82 patients developed a local recurrence and 289 distant metastases. LNR was an independent risk factor for OS, hazard ratio (HR) 2.10 (95% Cl 1.35-3.27) (in addition to age >= 65 years, involved circumferential resection margin (CRM) and new TNM stage) and LR, HR 2.25 (95% CI 1.02-4.56) (in addition to pre-operative radiotherapy and involved CRM). LNR is predictive of OS and LR from a lymph node yield of more than one and more than five respectively. A LNR value of 0.60 offers the best cut off to identify high risk patients (5-years OS was 61 vs. 32%, HR 2.45 (95% Cl 1.96-3.08) and 5-years LR rate 12.6 versus 16.3%, HR 1.65 (95% Cl 1.03-2.64)). Conclusions: LNR is an independent risk factor for OS and LR in addition to the 7th edition of the TNM classification. It can aid in predicting prognosis and identifying patients that should be considered for adjuvant treatment. (C) 2010 Elsevier Ltd. All rights reserved. Show less
Mesker, W.; Johnstone, E.; Pelt, G. van; Midgley, R.; Liefers, G.; Morreau, J.; ... ; Tollenaar, R. 2010
The third Human Variome Project (HVP) Meeting "Integration and Implementation" was held under UNESCO Patronage in Paris, France, at the UNESCO Headquarters May 10-14, 2010. The major aims of the... Show moreThe third Human Variome Project (HVP) Meeting "Integration and Implementation" was held under UNESCO Patronage in Paris, France, at the UNESCO Headquarters May 10-14, 2010. The major aims of the HVP are the collection, curation, and distribution of all human genetic variation affecting health. The HVP has drawn together disparate groups, by country, gene of interest, and expertise, who are working for the common good with the shared goal of pushing the boundaries of the human variome and collaborating to avoid unnecessary duplication. The meeting addressed the 12 key areas that form the current framework of HVP activities: Ethics; Nomenclature and Standards; Publication, Credit and Incentives; Data Collection from Clinics; Overall Data Integration and Access-Peripheral Systems/Software; Data Collection from Laboratories; Assessment of Pathogenicity; Country Specific Collection; Translation to Healthcare and Personalized Medicine; Data Transfer, Databasing, and Curation; Overall Data Integration and Access-Central Systems; and Funding Mechanisms and Sustainability. In addition, three societies that support the goals and the mission of HVP also held their own Workshops with the view to advance disease-specific variation data collection and utilization: the International Society for Gastrointestinal Hereditary Tumours, the Micronutrient Genomics Project, and the Neurogenetics Consortium. Show less
Gool, S.A. van; Wit, J.M.; Schutter, T. de; Clerck, N. de; Postnov, A.A.; Hovinga, S.K.; ... ; Karperien, M. 2010
Background: Estrogen deficiency induced by aromatase inhibitors may be a novel treatment modality for growth enhancement in short children, but may have adverse effects on bone, brain and... Show moreBackground: Estrogen deficiency induced by aromatase inhibitors may be a novel treatment modality for growth enhancement in short children, but may have adverse effects on bone, brain and reproduction. Aim: To assess growth effects and potential adverse effects of aromatase inhibition in male rats. Methods: 26-day-old prepubertal rats received intramuscular injections with placebo or the aromatase inhibitor exemestane at a dose of 10, 30 or 100 mg/kg/week [E10, E30, E100(6)] for 6 weeks, completely covering the sexual maturation phase, or with 3 weeks E100 followed by 3 weeks placebo [E100(3)]. Growth parameters and histology of the testis, seminal vesicle and brain were analyzed. Bone architecture was studied with X-ray microtomography. Results: Exemestane dose-dependently decreased body weight and tail length gain, as well as liver and seminal vesicle weights, but did not affect nose-anus length gain, Show less
Baardewijk, Y. van; Andershed, H.; Stegge, H.; Nilsson, K.W.; Scholte, E.; Vermeiren, R. 2010
The adolescent Youth Psychopathic Traits Inventory (YPI) and its child version (YPI-CV) are sound but lengthy instruments for measuring psychopathic traits in youths. The current study develops... Show moreThe adolescent Youth Psychopathic Traits Inventory (YPI) and its child version (YPI-CV) are sound but lengthy instruments for measuring psychopathic traits in youths. The current study develops psychometrically strong short versions of these instruments. Samples used for item reduction were community samples of adolescents (n = 2105, age 16-19, 49% boys) and children (n = 360, age 9-12, 52% boys). Stepwise parallel reduction using principal components analyses and content-related arguments resulted in two highly similar short instruments of 18 items each. In both versions, near identical and theoretically comprehensible three factor structures were demonstrated, which were crossvalidated in independent samples (CFI = .97 and .97; RMSEA = .044 and .038, respectively). Results were similar for boys and girls. The short instruments were reliable (Cronbach's alpha s of .85 and .83) and covered all core characteristics of the psychopathic personality construct. The short versions showed a high convergence with the original long instruments (r =.95 and .93, respectively) and similar correlations to external criterion measures of conduct problems. Therefore, the abbreviated versions are practical and valid alternatives for the original YPIs when administration time is limited. Show less
![NEW AND KNOWN beta-THALASSEMIA DETERMINANTS MASKED BY KNOWN AND NEW delta GENE DEFECTS [Hb A(2)-Ramallah OR delta 6(A3)Glu -> Gln, GAG >> CAG]](/sites/all/modules/custom/islandora_solr_search/images/defaultimg.png?solr_nav%5Bid%5D=3f3e0e9a0b5d6e6e77e2&solr_nav%5Bpage%5D=0&solr_nav%5Boffset%5D=9)
