Factorial validity and measurement invariance of the Perceived Susceptibility to Sport Injury scale.

The Perceived Susceptibility to Sport Injury (PSSI) scale is a measure that has recently surfaced in the sport injury literature. The factor structure of the PSSI scale has not been subjected to a rigorous factor analysis; thus, the factorial validity of the measure in athlete populations is unknown. To establish the validity of the PSSI scale in sports medicine research, the purpose of this study was to examine the factor structure and measurement invariance across gender of the PSSI scale. Male and female intercollegiate athletes (N = 217) completed the PSSI scale during the off-season. The factor structure was analyzed using confirmatory factor analysis (CFA) procedures and maximum likelihood estimation. The measurement invariance analysis was conducted via comparisons of fit indices within a series of hierarchically constrained models. Results of the CFA yielded a very good fit of the measurement model: χ2 (2) = 4.535, P = 0.104; RMSEA = 0.076; SRMR = 0.018; CFI = 0.995; NNFI = 0.985. Results of the measurement invariance analysis demonstrated strict invariance across gender, and no significant latent mean differences emerged between men and women. Study results support the factorial validity of the PSSI scale for use in future sports medicine research.

Uncoiling collagen: a multidimensional mass spectrometry study.

Mass spectrometry can be used to determine structural information about ions by activating precursors and analysing the resulting series of fragments. Two-dimensional Fourier transform ion cyclotron resonance mass spectrometry (2D FT-ICR MS) is a technique that correlates the mass-to-charge (m/z) ratio of fragment and precursor ions in a single spectrum. 2D FT-ICR MS records the fragmentation of all ions in a sample without the need for isolation. To analyse specific precursors, horizontal cross-sections of the spectrum (fragment ion scans) are taken, providing an alternative to conventional tandem mass spectrometry (MS/MS) experiments. In this work, 2D FT-ICR MS has been used to study the tryptic digest of type I collagen, a large protein. Fragment ion scans have been extracted from the 2D FT-ICR MS spectrum for precursor m/z ratios: 951.81, 850.41, 634.34, and 659.34, and 2D FT-ICR MS spectra are compared with a set of 1D MS/MS spectra using different fragmentation methods. The results show that two-dimensional mass spectrometry excells at MS/MS of complex mixtures, simplifying spectra by eliminating contaminant peaks, and aiding the identification of species in the sample. Currently, with desktop computers, 2D FT-ICR MS is limited by data processing power, a limitation which should be alleviated using cluster parallel computing. In order to explore 2D FT-ICR MS for collagen, with reasonable computing time, the resolution in the fragment ion dimension is limited to 256k data points (compared to 4M data points in 1D MS/MS spectra), but the vertical precursor ion dimension has 4096 lines, so the total data set is 1G data points (4 Gbytes). The fragment ion coverage obtained with a blind, unoptimized 2D FT-ICR MS experiment was lower than conventional MS/MS, but MS/MS information is obtained for all ions in the sample regardless of selection and isolation. Finally, although all 2D FT-ICR MS peak assignments were made with the aid of 1D FT-ICR MS data, these results demonstrate the promise of 2D FT-ICR MS as a technique for studying complex protein digest mixtures.

Chemical fingerprinting of naphthenic acids and oil sands process waters-A review of analytical methods for environmental samples.

This article provides a review of the routine methods currently utilized for total naphthenic acid analyses. There is a growing need to develop chemical methods that can selectively distinguish compounds found within industrially derived oil sands process affected waters (OSPW) from those derived from the natural weathering of oil sands deposits. Attention is thus given to the characterization of other OSPW components such as oil sands polar organic compounds, PAHs, and heavy metals along with characterization of chemical additives such as polyacrylamide polymers and trace levels of boron species. Environmental samples discussed cover the following matrices: OSPW containments, on-lease interceptor well systems, on- and off-lease groundwater, and river and lake surface waters. There are diverse ranges of methods available for analyses of total naphthenic acids. However, there is a need for inter-laboratory studies to compare their accuracy and precision for routine analyses. Recent advances in high- and medium-resolution mass spectrometry, concomitant with comprehensive mass spectrometry techniques following multi-dimensional chromatography or ion-mobility separations, have allowed for the speciation of monocarboxylic naphthenic acids along with a wide range of other species including humics. The distributions of oil sands polar organic compounds, particularly the sulphur containing species (i.e., OxS and OxS2) may allow for distinguishing sources of OSPW. The ratios of oxygen- (i.e., Ox) and nitrogen-containing species (i.e., NOx, and N2Ox) are useful for differentiating organic components derived from OSPW from natural components found within receiving waters. Synchronous fluorescence spectroscopy also provides a powerful screening technique capable of quickly detecting the presence of aromatic organic acids contained within oil sands naphthenic acid mixtures. Synchronous fluorescence spectroscopy provides diagnostic profiles for OSPW and potentially impacted groundwater that can be compared against reference groundwater and surface water samples. Novel applications of X-ray absorption near edge spectroscopy (XANES) are emerging for speciation of sulphur-containing species (both organic and inorganic components) as well as industrially derived boron-containing species. There is strong potential for an environmental forensics application of XANES for chemical fingerprinting of weathered sulphur-containing species and industrial additives in OSPW.

Preliminary fingerprinting of Athabasca oil sands polar organics in environmental samples using electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry.

There is a growing need to develop analytical methods that can distinguish compounds found within industrially derived oil sands process water (OSPW) from those derived from natural weathering of oil sands deposits. This is a difficult challenge as possible leakage beyond tailings pond containments will probably be in the form of mixtures of water-soluble organics that may be similar to those leaching naturally into aquatic environments. We have evaluated the potential of negative ion electrospray ionization high-resolution Fourier transform ion cyclotron resonance mass spectrometry (FTICRMS) for comparing oil sands polar organics from tailing ponds, interceptor wells, groundwater, river and lake surface waters. Principal component analysis was performed for all species observed. which included the O(2) class (often assumed to be monocarbxoylic naphthenic acids) along with a wide range of other species including humic substances in the river and lake samples: O(n) where n=1-16; NO(n) and N(2)O(n) where n=1-13; and O(n)S and O(n)S(2) where n=1-10 and 1-8, respectively. A broad range of species was investigated because classical naphthenic acids can be a small fraction of the 'organics' detected in the polar fraction of OSPW, river water and groundwater. Aquatic toxicity and environmental chemistry are attributed to the total organics (not only the classical naphthenic acids). The distributions of the oil sands polar organics, particularly the sulfur-containing species, O(n)S and O(n)S(2), may have potential for distinguishing sources of OSPW. The ratios of species containing O(n) along with nitrogen-containing species: NO(n), and N(2)O(n), were useful for differentiating organic components derived from OSPW from those found in river and lake waters. Further application of the FTICRMS technique for a diverse range of OSPW of varying ages and composition, as well as the surrounding groundwater wells, may be critical in assessing whether leakage from industrial sources to natural waters is occurring.

Review of perinatal management of arthrogryposis at a large UK teaching hospital serving a multiethnic population.

OBJECTIVE: To review the prevalence and perinatal management of cases of arthrogryposis delivering at our hospital over a 6-year period. METHODS: This was a retrospective review of cases of arthrogryposis managed at a UK teaching hospital. Cases were identified from the regional congenital anomalies register and departmental databases. Case notes were reviewed and analysed. RESULTS: From 2002 to 2007, there were 27 cases of arthrogryposis. Sixteen (59.3%) were Caucasians, 7(25.9%) Asians and 4(14.8%) Afro-Caribbean; 17(63%) were nulliparous. In eight (29.6%) cases, there was a family history of congenital anomalies. Three had previously affected siblings and in three cases the parents were affected with arthrogryposis. Five (18.5%) were from consanguineous families. Eighteen (66.7%) cases were diagnosed prenatally at a mean gestational age of 21 weeks. Twelve (57%) were delivered by caesarean section. There were 18 live births. Sixteen (59%) cases were reviewed by clinical geneticist. Following detailed review and investigation including post-mortems, 20 (74%) of our cases had a formal diagnosis or likely cause identified. CONCLUSIONS: Suspected cases of arthrogryposis require multi-disciplinary management to optimise the possibility of making a diagnosis and providing parents with accurate information to enable them to make informed choices regarding the pregnancy and providing information regarding likelihood of recurrence.

Copy number changes of the microcephalin 1 gene (MCPH1) in patients with autism spectrum disorders.

Autism spectrum disorder (ASD) represents a set of neurodevelopmental disorders with a strong genetic aetiology. Chromosomal rearrangements have been detected in 5-10% of the patients with ASD, and recent applications of array comparative genomic hybridisation (aCGH) are identifying further candidate regions and genes. In this study, we present four patients who implicate microcephalin 1 (MCPH1) in band 8p23.1 as an ASD susceptibility gene. Patient 1 was a girl with a syndromic form of autistic disorder satisfying the Autism Diagnostic Interview-Revised (ADI-R), Autism Diagnostic Observation Schedule (ADOS) and Diagnostic and Statistical Manual of Mental Disorders (DSM-IV) criteria. Oligonucleotide aCGH (oaCGH) showed that she had a classic inv dup del(8)(qter-> p23.1::p23.1-> p21.2) containing at least three candidate genes; MCPH1 and DLGAP2 within the 6.9-Mb terminal deletion and NEF3 within the concomitant 14.1-Mb duplication. Three further patients with MCPH1 copy number changes were found using single-nucleotide polymorphism (SNP) array analysis in a cohort of 54 families with ASD patients. Our results show that ASD can be a component of the classical inv dup del(8) phenotype and identify changes in copy number of MCPH1 as a susceptibility factor for ASD in the distal short arm of chromosome 8.

Arterial tortuosity syndrome: clinical and molecular findings in 12 newly identified families.

Arterial tortuosity syndrome (ATS) is a rare autosomal recessive connective tissue disease, characterized by widespread arterial involvement with elongation, tortuosity, and aneurysms of the large and middle-sized arteries. Recently, SLC2A10 mutations were identified in this condition. This gene encodes the glucose transporter GLUT10 and was previously suggested as a candidate gene for diabetes mellitus type 2. A total of 12 newly identified ATS families with 16 affected individuals were clinically and molecularly characterized. In addition, extensive cardiovascular imaging and glucose tolerance tests were performed in both patients and heterozygous carriers. All 16 patients harbor biallelic SLC2A10 mutations of which nine are novel (six missense, three truncating mutations, including a large deletion). Haplotype analysis suggests founder effects for all five recurrent mutations. Remarkably, patients were significantly older than those previously reported in the literature (P=0.04). Only one affected relative died, most likely of an unrelated cause. Although the natural history of ATS in this series was less severe than previously reported, it does indicate a risk for ischemic events. Two patients initially presented with stroke, respectively at age 8 months and 23 years. Tortuosity of the aorta or large arteries was invariably present. Two adult probands (aged 23 and 35 years) had aortic root dilation, seven patients had localized arterial stenoses, and five had long stenotic stretches of the aorta. Heterozygous carriers did not show any vascular anomalies. Glucose metabolism was normal in six patients and eight heterozygous individuals of five families. As such, overt diabetes is not related to SLC2A10 mutations associated with ATS.

Rheometry and associated techniques for blood coagulation studies.

This review considers various rheometrical approaches that have been adopted to study blood coagulation, with special reference to the rheological assessment of clotting time and studies of the evolution of viscoelasticity during the course of fibrin polymerization and cross-linking. The significance of the Gel Point in blood coagulation studies is discussed as a common feature of many of these studies in that they attempt to detect a liquid-to-solid transition during coagulation. Coagulation studies based on various forms of complex shear modulus measurements are considered, the latter being based principally on controlled stress and controlled strain rheometers. Also considered are the long established technique of thromboelastography and several emerging techniques such as wave propagation measurements, free oscillation rheometry, quartz crystal microbalance measurements and surface plasmon resonance.

Studies of whole blood coagulation by oscillatory shear, thromboelastography and free oscillation rheometry.

We report studies of the coagulation of samples of whole human blood by oscillatory shear techniques, including Fourier Transform Mechanical Spectroscopy (FTMS). These techniques are used herein to identify the Gel Point of coagulating blood in terms of the Chambon-Winter Gel Point criterion which provides a rheometrical basis for detecting the establishment of an incipient clot. A comparison of the results of FTMS with those obtained from measurements involving a Thromboelastograph (TEG) and a Free Oscillation Rheometer (FOR) indicate that the latter techniques are not capable of detecting the incipient clot, whose establishment occurs several minutes prior to TEG or FOR-based assessments of clot formation time. The results of the present study suggest that FTMS is a useful tool in blood clotting research, being capable of providing a global coagulation profile in addition to detecting the instant of incipient clot formation.

Juvenile idiopathic arthritis flare due to rice bodies in the knee of a 10-year-old girl.

A 10-year-old girl with juvenile idiopathic arthritis in remission presented with a flare of her arthritis. All her joints responded to treatment except the right knee, despite the use of disease-modifying antirheumatic drugs, non-steroidal anti-inflammatory medication and high-dose cortisone. A magnetic resonance imaging scan showed a knee densely packed with rice bodies. After surgical removal of the rice bodies the inflammation settled once again, and the patient remains well on her usual medication.

Rheometrical and computational studies of blood viscoelasticity during coagulation.

The rheological behaviour of coagulating human blood has been measured using multiple strain wave frequencies. The results indicate that coagulating blood, prior to the point of incipient clot formation, can be modelled by a modified form of the Gross-Marvin 'ladder' model, and the benefits of such modeling for blood coagulation are discussed.

Protein kinase C (calcium/phospholipid-dependent protein kinase) in developing chick heart: selective localization to atrium versus ventricle and changes in activity levels during cardiogenesis.

Activity levels of calcium/phospholipid-dependent protein kinase were examined in preparations of atria and ventricles from embryonic chick hearts at various stages of development. Activity of protein kinase C was much higher in atria than ventricles. Protein kinase C activity underwent a progressive increase in atria during cardiogenesis, being highest just prior to hatching, followed by a profound decrease in activity after hatching. In contrast, activity of cyclic AMP-dependent protein kinase (protein kinase A), while also higher in atria than ventricles, remained relatively constant at the developmental stages examined, likewise decreasing following hatching. These progressive changes in atrial protein kinase C activity suggest a potential regulatory role for this enzyme in cardiogenesis.

Angelman syndrome phenotype associated with mutations in MECP2, a gene encoding a methyl CpG binding protein.

Angelman syndrome (AS) is a neurodevelopmental disorder characterised by severe mental retardation, absent speech, ataxia, sociable affect, and dysmorphic facial features. Eighty five percent of patients with AS have an identifiable genetic abnormality of chromosome 15q11-13. Mutations within the X linked MECP2 gene have been identified in patients with Rett syndrome (RTT), a neurodevelopmental disorder which affects females almost exclusively and which shares phenotypic overlap with AS. RTT is usually associated with normal development in infancy followed by loss of acquired skills and evolution of characteristic hand wringing movements and episodes of hyperventilation.A panel of 25 female and 22 male patients with a clinical diagnosis of AS and no molecular abnormality of 15q11-13 were screened for MECP2 mutations and these were identified in four females and one male. Following the diagnosis, it was possible to elicit a history of regression in three of these patients, who by then were showing features suggestive of Rett syndrome. In the remaining two subjects the clinical phenotype was still considered to be Angelman-like. These findings illustrate the phenotypic overlap between the two conditions and suggest that screening for MECP2 mutations should be considered in AS patients without a demonstrable molecular or cytogenetic abnormality of 15q11-13. Since MECP2 mutations almost always occur de novo, their identification will substantially affect genetic counselling for the families concerned.

Affective disorder in juvenile offenders: A preliminary study.

OBJECTIVE: The authors' goal was to determine the prevalence of major mental disorders and substance abuse in adolescents admitted to a juvenile detention center. METHOD: As part of a routine mental health screening, modules from the Diagnostic Interview Schedule for Children were administered to 50 youths (11-17 years old) at an urban juvenile detention center. RESULTS: A high rate of affective disorder (42%) was found among these adolescents: 10 (20%) met criteria for mania, another 10 met criteria for major depressive disorder, and one met criteria for bipolar disorder, mixed type. Thirty (60%) met criteria for conduct disorder, and very high rates of alcohol, marijuana, and other substance dependence were found. There was a strong association between affective disorder and conduct disorder; adolescents with mania had much higher rates of reported abuse of substances other than alcohol or marijuana. CONCLUSIONS: Juvenile offenders have high rates of affective disorder. Further studies are needed to examine the relationship of affective disorder to substance abuse as well as to antisocial behavior.

Diaphragmatic hernia, exomphalos, absent corpus callosum, hypertelorism, myopia, and sensorineural deafness: a newly recognized autosomal recessive disorder?

We describe unrelated male and female patients with an identical syndrome of diaphragmatic hernia, exomphalos, hypertelorism, agenesis of the corpus callosum, severe sensorineural deafness, and severe myopia. One child had an iris coloboma. After the birth of the first affected child in each family subsequent pregnancies were monitored with ultrasound scan and a further affected fetus was identified in both families. We conclude that this constellation of anomalies represents a distinct, previously unreported syndrome with likely autosomal recessive inheritance.

Bone dysplasia, midface hypoplasia, and deafness: three new patients and review of the literature.

We report on 3 unrelated patients with a syndrome of sensorineural deafness (3/3), midface hypoplasia (3/3), disproportionate shortness with short limbs (3/3), cleft palate or bifid uvula (3/3), and lack of high myopia (3/3). This brings the number of reported patients with this condition to 11. Different names such as oto-spondylo-megaepiphyseal dysplasia (OSMED) or the Insley-Astley syndrome have been used. We propose the name "syndrome of bone dysplasia, midface hypoplasia, and deafness" which lists the 3 main manifestations of the condition.

MR in children with L-carnitine deficiency.

PURPOSE: To describe the MR imaging findings in five children with proved L-carnitine deficiency. METHODS: MR imaging studies (five without contrast, two with contrast) were obtained in five children (mean age, 9 years) who presented with stroke symptoms and who proved to have L-carnitine deficiency as established by serum levels. RESULTS: In three of five patients, infarctions were confined to arterial distributions; one patient had a hemorrhagic infarction in one frontoparietal region; and one patient had only nonspecific periventricular white matter T2 hyper-intensities. Serum L-carnitine levels normalized after correction; sequelae included seizures in two patients, hemiparesis in one patient, normal outcome in one patient, and death in one patient. CONCLUSION: L-Carnitine deficiency is a rare metabolic disorder leading to cerebral infarctions, as seen in our five patients, and should be considered in the differential diagnosis of children who have had a stroke, particularly when associated with hypoglycemia and myopathy.

Applicability of early indicators of iron toxicity.

Leukocytosis, blood glucose, vomiting, diarrhea, and abdominal radiograph have been reported as early indicators of toxic serum iron levels. To test the applicability of this battery of five variables, the charts of 64 patients admitted for toxic iron ingestion were reviewed. When these variables were subjected to tests of sensitivity, specificity, and predictive negative and positive values in 42 patients meeting study criteria, they failed to reach statistical significance. Only vomiting was found to approach statistical significance and, therefore, may serve as an early indicator of toxicity. In addition, several epidemiological issues relevant to the study population are discussed.

Pterygia associated with otomandibular anomalies: a new autosomal recessive condition?

We report a male baby with an unusual pattern of malformations comprising severe micrognathia, ear abnormalities and popliteal and elbow webbing. Absence of a single phalanx in the fifth finger of each hand was also noted. Although there is no clear diagnosis there is a history of parental consanguinity and we suggest this may represent a new autosomal recessive disorder.

Role of routine fluid replacement in children undergoing tonsillectomy.

It has been suggested that children undergoing tonsillectomy would benefit from an intravenous infusion, to counteract the period of pre-operative fasting combined with the blood loss at operation. A prospective study of 50 children undergoing tonsillectomy was undertaken. The children were randomly allocated into two groups, one to receive an infusion and a control group. There were no significant differences between the two groups, although the children with an infusion had a longer mean post-operative stay. There would seem to be no role for routine intravenous fluid replacement in children undergoing uncomplicated tonsillectomy.