Computed tomography for cervical spine trauma. The impact of MDCT on fracture detection and dose deposition

A multidetector computed tomography (MDCT) was installed in our department. Referral rates, examination protocols and detection rates of abnormal findings in CT examinations for cervical spine trauma 6 months before and 6 months after MDCT installation were compared to look for changes in practice. Retrospective analysis of all CT cervical spine examinations in patients with multiple trauma over two contiguous 6-month periods: from July 2003 to December 2003 (helical CT) and from January 2004 to June 2004 (MDCT). Variables recorded were number of CT examinations performed, scan plane coverage and traumatic abnormalities detected. Phantom dosimetry measurements for cervical spine examination in both helical CT and MDCT were compared. One hundred and fifty four patients underwent cervical spine CT during these periods. Helical CT period: of 91 patients undergoing CT cervical spine examination for trauma, 65 (71%) were complete cervical examinations and 26 (29%) were level-specific examinations. Eight patients (9%) had cervical spine fracture, six of which were apparent on radiographs. Dose estimations for thyroid, lens and breast were 24.76, 1.86 and 0.21 mGy, respectively, for complete cervical spine examinations. MDCT period: of 63 patients who underwent CT cervical spine examination for trauma, 61 (97%) were complete examinations and 2 (3%) were level-specific examinations. Six patients (11%) had cervical spine fracture, three of which were apparent on radiographs. Dose estimations for thyroid, lens and breast were 75.8, 9.7 and 0.7 mGy, respectively, for complete cervical spine examinations, which were notably higher than those for helical CT. After installation of MDCT, clinical requests for complete examination of the cervical spine following trauma increased. This changing trend resulted in a significantly higher radiation dose to thyroid, lens and breast.     

Fetal karyotype following ascertainment of fetal anomalies by ultrasound

Data pooled from contributors to a Registry for Cytogenetic Abnormalities and PKU (ReCAP) shows an unbalanced chromosome abnormality rate of 27 per cent (29 fetuses) for 107 fetuses with ultrasonically diagnosed fetal anomalies. Of the abnormal, 12 were trisomic, 6 were monosomy X and 6 were structural abnormalities, 4 were mosaics and one triploid.     

An association between skewed X-chromosome inactivation and abnormal outcome in mosaic trisomy 16 confined predominantly to the placenta

Skewed X-chromosome inactivation (XCI) is frequently found in the diploid fetal tissues of individuals with mosaic trisomy that originated from a 'trisomic zygote rescue' event. This may result from a high number of trisomic cells in the embryonic cell pool at the time of XCI, which are subsequently eliminated by selection. We hypothesize that extremely skewed XCI in these mosaic cases will be associated with a poor fetal outcome due to failure to completely eliminate the trisomy from all fetal tissues. To test this hypothesis, XCI status was evaluated in 17 cases of prenatally detected trisomy 16 mosaicism. Ten of the 15 informative cases showed extreme XCI skewing ( > or = 90% inactivation of one allele) in blood or other diploid fetal tissues compared to six of the 111 controls (p < 0.001). Among these 10 'skewed' cases, 6 showed an abnormal outcome, defined as developmental abnormalities and/or intrauterine or neonatal death. In contrast, of the 5 cases without extreme skewing, none showed abnormal outcome, although outcome information was incomplete in 1 case. An additional 6 cases analyzed, involving trisomy mosaicism for other chromosomes, showed similar results. Further studies are warranted to determine if XCI status adds useful information to the prediction of pregnancy outcome in prenatally detected mosaic trisomy.     

Screening of mentally retarded males for macro-orchidism and the fragile X chromosome

Four hundred forty-four male residents of a state mental retardation institution were screened for macro-orchidism. Twenty-six white males (8.3%) and two black males (1.5%) had marked macro-orchidism (>34 ml). Seven of 17 whites tested for the fragile X were positive; the one black tested was negative. Thus, a minimum of 7/26 or 27% (whites) are fragile X positive indicating potential population variability, also evident from previous reports. Concurrent testing of institutionalized brother pairs indicated over half of the fragile X-positive males had a strong family history consistent with X-linked mental retardation.     

Submicroscopic deletions in the Y chromosome of infertile men

Recent investigations have suggested a high prevalence of Y chromosome submicroscopic deletions in men with severely impaired spermatogenesis. We evaluated the frequency of Y chromosome deletions in 160 infertile men using a series of 36 sequence-tagged-sites, emphasizing intervals 5 and 6 of the long arm of the Y chromosome. Peripheral leukocyte DNA was extracted and amplified with two parallel techniques to minimize potential overestimation of the frequency of deletions. The presence of deletions was evaluated relative to patient's sperm concentration, testis volume, and hormonal parameters. Men with sperm concentration <5 x 10(6)/ml had a 7% prevalence of submicroscopic Y chromosome deletions. Deletions were detected in 7% of azoospermic men, 10% of men with <1 x 10(6) spermatozoa/ml, and 8% of men with >1 x 10(6) but <5 x 10(6) spermatozoa/ml. Other clinical parameters did not identify men with Y chromosome deletions prior to polymerase chain reaction (PCR)- based testing for the presence of sequence-tagged-sites. Two distinct regions of Y chromosome deletions were detected, approximately 3.6 Mb and 1.4 Mb in length respectively. These deleted regions are present in AZFb and AZFc respectively. No deletions were detected in AZFa. The loss of these two distinct areas is supported by the finding of highly repetitive sequences along the Y chromosome, predisposing to deletion of specific intervals on the Y chromosome during meiosis. Men with severe male infertility are at high risk for Y chromosome deletions. Testing of men for these genetic abnormalities is indicated prior to treatment with assisted reproduction.      

A complex chromosome rearrangement resulting in trisomy 15q22→qter

A black infant with malformations was found to have trisomy 15q22→qter. The mother had a complex chromosomal rearrangement involving three chromosomes (5, 13, and 15). A comparison with previously published cases of trisomy for distal 15q suggests a pattern of clinical findings including retardation in growth and development, microcephaly, asymmetrical facies, prominent occiput, antimongoloid slant of the palpebral fissures, micrognathia, prominent nose, and congenital heart disease.     

Disaggregation and invasion of ovarian carcinoma ascites spheroids

Background  

Malignant ascites often develops in advanced stages of ovarian carcinoma, consisting of single and aggregated tumor cells, or spheroids. Spheroids have commonly been used as tumor models to study drug efficacy, and have shown resistance to some chemotherapies and radiation. However, little is known about the adhesive or invasive capabilities of spheroids, and whether this particular cellular component of the ascites can contribute to dissemination of ovarian cancer. Here, we examined the invasive ability of ascites spheroids recovered from seven ovarian carcinoma patients and one primary peritoneal carcinoma (PPC) patient.     

Localization of dystrophin isoform Dp71 to the inner limiting membrane of the retina suggests a unique functional contribution of Dp71 in the retina

The electroretinograms (ERGs) of patients with Duchenne muscular dystrophy and an allelic variant of the mdx mouse (mdxCv3) have been shown to be abnormal. Analysis of five allelic variants of the mdx mouse with mutations in the dystrophin gene has shown that there is a correlation between the position of the mutation and the severity of the ERG abnormality. Three isoforms are expressed in the retina: Dp427, Dp260 and Dp71. Using indirect immunofluorescence and isoform-specific antibodies on retinal sections from three allelic mdx mouse strains, we have examined the localization of each of the isoforms. We show that Dp71 expression does not overlap with Dp427 and Dp260 expression at the outer plexiform layer (OPL). Instead, Dp71 is localized to the inner limiting membrane (ILM) and to retinal blood vessels. Moreover, we show that Dp260 and Dp71 differ structurally at their respective C-termini. In addition, we find that the proper localization of the beta- dystroglycan is dependent upon both Dp260 at the OPL and Dp71 expression at the ILM. Thus, Dp260 and Dp71 are non-redundant isoforms that are located at different sites within the retina yet have a common interaction with beta-dystroglycan. Our data suggest that both Dp71 and Dp260 contribute distinct but essential roles to retinal electrophysiology.      

Longitudinal changes in cognitive and adaptive behavior in fragile X females: a prospective multicenter analysis

In prospective studies of young, fragile X [fra(X)] males with the full mutation, cognitive abilities (IQ scores) and adaptive behavior levels (DQ scores) declined in most subjects tested. Little is known about longitudinal changes in IQ and DQ scores in young fra(X) females, although one earlier retrospective study showed declines in IQ scores in 8 of 11 subjects. To examine fra(X) females prospectively, we tested and retested 13 females with the full mutation, age 4 to 15 years. Nine were tested and retested in North America, and four were evaluated at the Catholic University in Leuven, Belgium. Cognitive abilities of North American females were measured using the Stanford-Binet 4th Edition. Adaptive behavior levels were ascertained from the Vineland Adaptive Behavior Scales. For Belgians, test-retest scores from the Wechsler Intelligence Scales for Children-Revised were used. Subjects were subsequently separated into two age cohorts: those tested initially before age 7 years and those tested initially after age 7 years. Compared with young males with the full mutation and of the same age, females expectedly display a wider range of IQ scores. Test-retest IQ scores showed statistically significant decreases (P < 0.03). Analysis of individual test-retest scores indicate that declines in eight females were statistically significant. Adaptive behavior scores were available only for North American females. Five of nine (55%) showed significant declines in DQ. Like young males with the full mutation, all females with the full mutation attained higher adaptive behavior levels than cognitive scores, i.e., DQ > IQ.     

Perceived prevalence of peanut allergy in Great Britain and its association with other atopic conditions and with peanut allergy in other household members

BACKGROUND: Despite increasing awareness of peanut allergy, little is known of its prevalence. We report on a two-stage interview survey conducted in Great Britain. METHODS: A total of 16434 adults (aged 15+ years) reported their own allergies and atopies and named cohabitants with peanut allergy (stage 1). Follow-up interviews were conducted with identified sufferers from peanut allergy (stage 2). RESULTS: At stage 1, peanut allergy was reported in 58 respondents and 205 other household members. When we accounted for cases where peanut allergy was unconfirmed or newly reported at stage 2, the prevalence, based on 124 confirmed sufferers, was estimated as 0.48% (95% confidence interval 0.40%-0.55%). The prevalence in children (0.61%, 0.41%-0.82%) was slightly higher than in adults; age-of-onset was strikingly earlier. Prevalence was strongly associated with other atopies, particularly tree-nut allergy. Cases tended significantly to cluster in households. Half of cases had never consulted a doctor. Exactly 7.4% reported being hospitalized after a reaction. CONCLUSIONS: Peanut allergy is reported by 1 in 200 of the population and is commoner in those reporting other atopies. The fact of similar rates in children and adults argues against a recent marked rise in prevalence. The frequency and potential lethality of this disorder emphasize the need for sufferers to demographic factors, other food allergies, atopic conditions, and allergy in family/household members. Our study comprised a screening survey and detailed interviews with sufferers identified. The frequency and potential lethality of this disorder emphasize the need for sufferers to receive correct medical advice on management [corrected].