Efficacy and safety of coronary computed tomography angiography in diagnosing coronary lesions in children.

INTRODUCTION: Identification of paediatric coronary artery abnormalities is challenging. We studied whether coronary artery CT angiography can be performed safely and reliably in children. MATERIALS: Retrospective analysis of consecutive coronary CT angiography scans was performed for image quality and estimated radiation dose. Both factors were assessed for correlation with electrocardiographic-gating technique that was protocoled on a case-by-case basis, radiation exposure parameters, image noise artefact parameters, heart rate, and heart rate variability. RESULTS: Sixty scans were evaluated, of which 96.5% were diagnostic for main left and right coronaries and 91.3% were considered diagnostic for complete coronary arteries. Subjective image quality correlated significantly with lower heart rate, increasing patient age, and higher signal-to-noise ratio. Estimated radiation dose only correlated significantly with choice of electrocardiographic-gating technique with median doses as follows: 2.42 mSv for electrocardiographic-gating triggered high-pitch spiral technique, 5.37 mSv for prospectively triggered axial sequential technique, 3.92 mSv for retrospectively gated technique, and 5.64 mSv for studies which required multiple runs. Two scans were excluded for injection failure and one for protocol outside the study scope. Five non-diagnostic cases were attributed to breathing motion, scanning prior to peak contrast enhancement, or scan acquisition during the incorrect portion of the R-R interval. CONCLUSIONS: Diagnostic-quality coronary CT angiography can be performed reliably with a low estimated radiation exposure by tailoring each scan protocol to the patient's body habitus and heart rate. We propose coronary CT angiography is a safe and effective diagnostic modality for coronary artery abnormalities in children.

Tibial Intraosseous Insertion in Pediatric Emergency Care: A Review Based upon Postmortem Computed Tomography.

Objective: The proximal tibia is a recommended and commonly used site for pediatric emergency intraosseous vascular access (IO). During forensic whole body postmortem computed tomography (PMCT), we evaluated accuracy of emergency placement of tibial IO access.Methods: We conducted a retrospective review of 92 state medical examiner cases to assess presence and placement of tibial IO needles. Insertions were classified as successful (needle tip in the medullary portion of the bone) or unsuccessful (all other non-medullary placements) based upon position of the needle tip. Medical records were reviewed for patient age, equipment, and where an insertion was attempted, as well as if IO placement occurred in a prehospital or hospital environment.Results: Thirty-one cases with 42 tibial devices (aged 3 weeks to 16 years, median 4 months) were identified. In 25 insertions (60%), the needle tip was in satisfactory position. In 17 placements (40%), needle tip was unsatisfactory and included tibia perforation (6), tip embedded in the cortex (6), and needle missed the bone (5). In patients older than 6 months, all six placements of a 15-mm needle were successful. In infants age 6 months or younger, 14 placements (56%) were successful and 11 (44%) unsuccessful. The 25-mm IO needle was successfully placed in five of six children older than 6 months. In infants age 6 months or younger, the 25-mm needle was unsuccessfully placed in five of five attempts.Conclusion: In infants 6 months of age or younger, tibial IO needle insertion had a 53% failure rate (non-medullary placement). Failures occur during both prehospital and emergency department care. In infants age 6 months or younger, use of a 25-mm needle should be avoided. Procedures for IO insertion in infants age 6 months or younger should be reviewed and modification considered.

Pediatric postmortem computed tomography: initial experience at a children's hospital in the United States.

Postmortem CT might provide valuable information in determining the cause of death and understanding disease processes, particularly when combined with traditional autopsy. Pediatric applications of postmortem imaging represent a new and rapidly growing field. We describe our experience in establishing a pediatric postmortem CT program and present a discussion of the distinct challenges in developing this type of program in the United States of America, where forensic practice varies from other countries. We give a brief overview of recent literature along with the common imaging findings on postmortem CT that can simulate antemortem pathology.

Microbial community structure during fluoranthene degradation in the presence of plants.

AIMS: To investigate bacterial and fungal community structure during degradation of varying concentrations (0-5000 mg kg(-1) ) of the polycyclic aromatic hydrocarbon (PAH) fluoranthene in the presence or absence of tomato plants. METHOD AND RESULTS: Fluoranthene amended or unamended growing media, with or without a plant, were incubated in pots in a glasshouse for 30 days. Fluoranthene concentration was quantified using GC-FID, while bacterial and fungal community structure was investigated using trflp and arisa, respectively. The abundance of two ring hydroxylating dioxygenase genes was measured using qPCR. More fluoranthene was degraded in the presence of tomato plants at 500 and 5000 mg fluoranthene kg(-1) (P < 0·001), and it had a toxic effect on plant growth. Bacterial and fungal community composition in the rhizosphere was significantly different from that in nonrhizospheric and unplanted samples. The influence of fluoranthene on bacterial communities overcame that of the plant root such that community composition in rhizosphere and planted nonrhizospheric samples was broadly similar when fluoranthene was present. PAH-RHDα-GP genes were more abundant than PAH-RHDα-GN genes in all treatments. PAH-RHDα-GN abundance was unaffected by either PAH concentration or growing medium type, while the abundance of PAH-RHDα-GP was greatest in the rhizosphere. CONCLUSIONS: Plants promoted microbial growth and diversity and led to increases in abundance of Gram-positive dioxygenase genes, correlated with increased degradation of fluoranthene. SIGNIFICANCE AND IMPACT OF THE STUDY: This work contributes to knowledge in the broad area of biodegradation and also provides useful information for the design of future bioremediation strategies.

Identification and management of prisoners with severe psychiatric illness by specialist mental health services.

BACKGROUND: The prevalence of mental disorders among prisoners is considerably higher than in the general population. This is an important public health issue as the vast majority of prisoners stay in custody for less than 9 months and, when not in prison, offenders' lifestyles are frequently chaotic, characterized by social exclusion, instability and unemployment. Multi-disciplinary mental health inreach services were introduced to target care towards prisoners with severe mental illness (SMI) in a similar way to that provided by Community Mental Health Teams outside prison. The aim was to establish the proportion of prisoners with SMI who were assessed and managed by prison mental health inreach services. Method A two-phase prevalence survey in six prisons in England measured SMI upon reception into custody. Case-note review established the proportion of those with SMI subsequently assessed and treated by inreach services. RESULTS: Of 3492 prisoners screened, 23% had SMI. Inreach teams assessed only 25% of these unwell prisoners, and accepted just 13% onto their caseloads. CONCLUSIONS: Inreach teams identified and managed only a small proportion of prisoners with SMI. Prison-based services need to improve screening procedures and develop effective care pathways to ensure access to appropriate services. Improved identification of mental illness is needed in both the community and the Criminal Justice System to better engage with socially transient individuals who have chaotic lifestyles and complex needs.

Hematopoietic cells and radioresistant host elements influence natural killer cell differentiation.

Radioresistant host elements mediate positive selection of developing thymocytes, whereas bone marrow-derived cells induce clonal deletion of T cells with receptors that are strongly autoreactive. In contrast to T cell development, little is known about the elements governing the natural killer (NK) cell repertoire, which, similar to the T cell repertoire, differs between individuals bearing different major histocompatibility complex (MHC) phenotypes. We have used murine bone marrow transplantation models to analyze the influence of donor and host MHC on an NK cell subset. We examined the expression of Ly-49, which is strongly expressed on a subpopulation of NK cells of H-2b mice, but not by NK cells of H-2a mice, probably because of a negative effect induced by the interaction of Ly-49 with Dd. To evaluate the effect of hematopoietic cell H-2a expression on Ly-49 expression of H-2b NK cells, we prepared mixed allogeneic chimeras by administering T cell-depleted allogeneic (B10.A, H-2a) and host-type (B10, H-2b) marrow to lethally irradiated B10 mice, or by administering B10. A marrow to B10 recipients conditioned by a nonmyeloablative regimen. Expression of H-2a on bone marrow-derived cells was sufficient to downregulate Ly-49 expression on both H-2a and H-2b NK cells. This downregulation was thymus independent. To examine the effect of H-2a expressed only on radioresistant host elements, we prepared fully allogeneic chimeras by administering B10 bone marrow to lethally irradiated B10.A recipients. B10 NK cells of these fully allogeneic chimeras also showed downregulation of Ly-49 expression. The lower level of H-2a expressed on H-2b x H-2a F1 cells induced more marked downregulation of Ly-49 expression on B10 NK cells when presented on donor marrow in mixed chimeras than when expressed only on radioresistant host cells. Our studies show that differentiation of NK cells is determined by interactions with MHC molecules expressed on bone marrow-derived cells and, to a lesser extent, by MHC antigens expressed on radioresistant host elements.

Fractures of the cervical vertebral odontoid in four horses and one pony.

Four horses and one pony, ranging in age from one to 11 years, were diagnosed with two different types of odontoid peg fractures. Their clinical signs included reluctance to move the neck and head, dullness, and abnormalities of gait. Radiography was essential for the diagnosis, and the method of treatment varied depending on the severity of the neurological signs, the intended use of the horse, and financial constraints. Optimal treatment requires a technique that allows decompression, anatomical alignment, and stabilisation of the odontoid fracture. If the clinical (neurological) signs are not too severe and the animal shows signs of feeling peripheral pain, conservative treatment can be applied, as is common practice in human surgery. All except the pony made a full recovery.

Neutrophils invade lumbar dorsal root ganglia after chronic constriction injury of the sciatic nerve.

To test whether neutrophils (PMN) target lumbar dorsal root ganglia (DRG) following axonal injury leading to neuropathic pain, we visualized PMN infiltration in DRG tissue sections and estimated PMN count by flow cytometry following sciatic chronic constriction injury (CCI). Seven days after CCI, results show PMN within DRG where their count increased by three fold ipsilateral to injury compared to contralateral or sham, concomitant with peak neuropathic pain behavior. Superoxide burst in PMN isolated from rats d7 after CCI was elevated by 170% +/-18 compared to naïve and MCP-1 mRNA expression in DRG increased by 8.9+/-2.9 fold, but that of MIP-2, CINC-1, and RANTES did not change. We conclude that CCI causes PMN invasion of the DRG whereby the functional implication of their close proximity to neuronal axon and soma remains unknown.

Reducing nitrous oxide emissions by changing N fertiliser use from calcium ammonium nitrate (CAN) to urea based formulations.

The accelerating use of synthetic nitrogen (N) fertilisers, to meet the world's growing food demand, is the primary driver for increased atmospheric concentrations of nitrous oxide (N2O). The IPCC default emission factor (EF) for N2O from soils is 1% of the N applied, irrespective of its form. However, N2O emissions tend to be higher from nitrate-containing fertilisers e.g. calcium ammonium nitrate (CAN) compared to urea, particularly in regions, which have mild, wet climates and high organic matter soils. Urea can be an inefficient N source due to NH3 volatilisation, but nitrogen stabilisers (urease and nitrification inhibitors) can improve its efficacy. This study evaluated the impact of switching fertiliser formulation from calcium ammonium nitrate (CAN) to urea-based products, as a potential mitigation strategy to reduce N2O emissions at six temperate grassland sites on the island of Ireland. The surface applied formulations included CAN, urea and urea with the urease inhibitor N-(n-butyl) thiophosphoric triamide (NBPT) and/or the nitrification inhibitor dicyandiamide (DCD). Results showed that N2O emissions were significantly affected by fertiliser formulation, soil type and climatic conditions. The direct N2O emission factor (EF) from CAN averaged 1.49% overall sites, but was highly variable, ranging from 0.58% to 3.81. Amending urea with NBPT, to reduce ammonia volatilisation, resulted in an average EF of 0.40% (ranging from 0.21 to 0.69%)-compared to an average EF of 0.25% for urea (ranging from 0.1 to 0.49%), with both fertilisers significantly lower and less variable than CAN. Cumulative N2O emissions from urea amended with both NBPT and DCD were not significantly different from background levels. Switching from CAN to stabilised urea formulations was found to be an effective strategy to reduce N2O emissions, particularly in wet, temperate grassland.

Therapeutic outcome as rated by patients, therapists, and judges.

The views of patients, therapists, and research judges were compared as to the degree of success attained in 22 cases of long-term psychotherapy and 15 cases of psychoanalysis. Across all cases, there was a tendency for therapists to overrate their success, as compared to the other two sources; this, together with a tendency of therapists to overlook or misperceive patients' dissatisfaction with treatment outcome, suggested that the failure to recognize and deal with the patient's negative feelings was a factor in a substantial number of unsuccessful treatments. The research judges rated the psychoanalytic cases as successful with much less frequency than either patients or treating analysts; the disparity seemed partly due to differing frames of reference, but may also have relected the participants' needs to feel that their efforts had been worthwhile.

Effect of crush lesion on ganglioside radiolabelling patterns in rat sciatic nerve.

Left sciatic nerves in rats were crushed and allowed to regenerate for variable periods of time up to 14 days; uncrushed right nerves from the same animals were used as controls. Two days before killing the rats, both L-5 dorsal root ganglia (DRG) were injected with 100 microcuries [3H]glucosamine. Gangliosides were purified separately from sciatic nerve (SN) distal to the crush site, lumbosacral trunk (LST) proximal to the crush site, and the injected DRG. Changes in major glycoconjugate classes were previously reported; in this study total gangliosides were separated by high performance thin layer chromatography, located by autofluorography and radioactivity was measured by liquid scintillography. In control DRG, major radiolabelled gangliosides were GM3 and LM1; in control LST and SN, GD1b and GT1b were the major ones. During day two and four following crush, GM3 and LM1 decreased in DRG, but at one and two weeks were at normal and elevated levels, respectively; there were inverse changes in GD3, GT1b and GQ1b. GD1b, GT1b and GQ1b were lower in crushed than in control LST and SN between days zero and four. In LST, GM3 and LM1 remained constant for four days, but were elevated at one and two weeks, whereas GD1a was elevated at all times. Indeed, GD1a is the major recently synthesized ganglioside that is transported into LST and SN two to four days after trauma, suggesting that it may play an important role in regeneration. Indices of oligosaccharide complexity and degree of sialylation indicated that between two and four days following crush, gangliosides in DRG had more complex oligosaccharides and more sialic acid residues than in either controls or in DRG of crushed nerves at one and two weeks post-crush. The degrees of ganglioside sialylation and oligosaccharide complexity in crushed LST and SN were lower than in control specimens between one and seven days after crush. Changes in the ganglioside composition of peripheral nerve following trauma may be important for axonal regeneration.

High-resolution CT in simple coal workers' pneumoconiosis. Lack of correlation with pulmonary function tests and arterial blood gas values.

We examined 21 miners by means of standard chest radiography, high-resolution computerized tomography (HRCT), pulmonary function tests, and resting arterial blood gas levels. Using the ILO/UC classification of pneumoconiosis, 7 miners had category 1/0 or 2/1 simple coal workers' pneumoconiosis (CWP). By HRCT, nodules were identified in 12 miners; 4 of 9 were classified as category 0/0 CWP; 2 of 5, 0/1 CWP; 5 of 6, 1/0 CWP; and 1 of 1, 2/1 CWP by chest radiograph. Focal emphysema was identified by HRCT in 7 miners; 4 of 9 were classified as 0/0 CWP; 2 of 5, 0/1 CWP; and 1 of 6, 1/0 CWP by standard chest radiography. Four miners with definite nodules confirmed by HRCT had focal emphysema, while three without nodules had focal emphysema. Pulmonary function testing was not different between miners with or without CWP by standard chest radiography, nor was it different between miners with or without definite nodules evidenced by HRCT. No difference in resting oxygenation was found between any group of miners. The presence of focal emphysema confirmed by HRCT did not significantly affect pulmonary function tests on resting arterial blood gas values. There was, however, a significantly lower FEV1 and mean forced expiratory flow during the middle half of forced vital capacity with lifetime nonsmoking miners. The presence of CWP on chest radiography was significantly correlated with smoking cigarettes but not the years of mining. The presence of nodules on HRCT approached a significant correlation with cigarette smoking, but focal emphysema did not. For detecting evidence of coal dust accumulation in lung parenchyma and identifying focal emphysema, HRCT was more sensitive than standard chest radiography. However, despite earlier detection of parenchymal abnormalities, abnormal pulmonary function attributable to coal dust could not be identified.

The effects of l-cycloserine on gangliosides in the developing mouse brain.

Marked changes in ganglioside composition occur during brain development and in cultured neurons concomitant with differentiation, and maximum ganglioside synthesis occurs during neuronal maturation and synaptogenesis. These findings indicate that gangliosides probably play an important role in brain development. In this study the effects of parenterally administered l-cycloserine (an inhibitor of sphingosine synthesis) on gangliosides during the period of rapid neonatal brain growth in mice were studied. Two groups of mice (saline control and l-cycloserine-20 mg/kg/day) were treated for 8 or 16 days, starting at postnatal day 6, and sacrificed at 14, 22, 32, 62 or 110 days of age. Undernourished controls were also sacrificed at the same times. Body and cerebral weights in the l-cycloserine group were less than those of saline control animals at early ages, but the l-cycloserine animals did not show sparing of cerebral weight in relation to body weight as did the undernourished controls. Compared to saline control animals the l-cycloserine group had significantly less total lipid extract and nonlipid residue over all age groups. Animals treated with l-cycloserine had less total ganglioside NeuNAc per hemisphere, but normal concentrations on a fresh weight basis. Both groups had identical ganglioside patterns. These results indicate that although l-cycloserine does affect some aspects of brain development, it is not useful as a selective inhibitor of ganglioside synthesis in neonatal ICR Swiss Webster mice treated with a dose equivalent to the LD-17. Its value in modifying ganglioside synthesis should be viewed with caution.

The effects of l-cycloserine on membrane fluidity and lipids of mouse brain.

l-Cycloserine can inhibit the synthesis of some sphingolipids, which may play a role in determining membrane fluidity. To evaluate the effects of l-cycloserine on neural cell membranes, adult mice were treated with 100 mg/kg of this drug twice daily for 1, 2, 4, 6, 13 and 17 days. Body weights in the treated mice decreased significantly. Cholesterol and total phospholipid per mass total lipid significantly increased with time. Fluorescence depolarization after the incorporation of diphenylhexatriene into membranes was measured in order to assess membrane fluidity. it increased significantly starting at treatment day 4, with a maximum increase in polarization value of 8%. These results show that l-cycloserine significantly changes the fluidity of brain membrane, but this does not correlate with changes in major lipid classes of the brain.

Imaging of pediatric foot disorders.

Imaging pediatric foot disorders is a challenging task. Optimally exposed and well-positioned radiographs can answer many questions. Because many bones may not be completely ossified, however, CT or MR imaging is often needed to provide additional information to assist in the management of congenital and acquired lesions in the foot.

A new tool for prenatal diagnosis: ultrafast fetal MRI.

The development of ultrafast magnetic resonance imaging scanners and sequences provides a new tool for the diagnosis of fetal anomalies. Magnetic resonance imaging is a valuable adjunct to prenatal ultrasound especially for the evaluation of suspected fetal brain anomalies, chest masses, abdominal masses, and renal diseases.

Serratus anterior paralysis in the young athlete.

Ten cases of isolated, complete paralysis of the serratus anterior muscle were diagnosed in young athletes during a three-year period. One patient had recurrent partial paralysis of the serratus anterior muscle, the first such case reported. From studies on cadavera and clinical observations, we concluded that paralysis of the serratus anterior muscle results from a traction injury to the long thoracic nerve of Bell. Since full recovery usually occurs in an average of nine months, surgical methods of treatment should be reserved for patients in whom function fails to return after a two-year period. Non-strenuous use of the involved extremity with avoidance of the precipitating activity, followed by exercises designed to maintain the range of motion of the shoulder and to increase the strength of associated muscles, is advocated for treatment of acute or repetitive injuries to the long thoracic nerve of Bell.

MR imaging of pediatric abnormalities in the ankle and foot.

MR imaging plays a valuable role in the evaluation of foot and ankle in infants and children. In young children with nonossified bones, MR imaging offers the advantage of effectively demonstrating the cartilaginous anlage in addition to soft tissue and bone marrow. The MR imaging examination is tailored to the clinical question, the child's age, foot size, and ability to cooperate. This article reviews the MR imaging of a number of familiar and uncommon disorders of the pediatric foot and ankle.

Symposium on Surface Replacement Arthroplasty of the Hip. Anatomic considerations.

Division of the joint capsule close to the level of the acetabular labrum provides the best protection for the essential vessels at the base of the neck and does not jeopardize the acetabular blood supply. The vital medial femoral circumflex artery passes posteriorly, directly below the neck, is afforded little protection by the tenuous inferior capsule, and must get careful consideration during joint exposure, especially if severance of the inferior capsule is contemplated. Low trochanterter osteotomy may injure the principal blood vessels to the superior neck and head. Efforts to stabilize an osteotomized greater trochanter by passing a screw or screws into the inferior neck-shaft junction throw a severe and unnecessary stress on this important weight-bearing region of the proximal femur. Deliberate cutting of the anterior edge of the gluteus minimus from the underlying anterior joint capsule (iliotrochanteric band) facilitates capsular exposure.

Ovarian torsion: clinical and imaging presentation in children.

Ovarian torsion is uncommon and has a nonspecific clinical presentation. To determine the impact of imaging on clinical management, the authors reviewed their recent experience with 12 children who had a total of 13 episodes of ovarian torsion. Three children presented as neonates, six were premenarchal, and three were postmenarchal. Ultrasound was the imaging study of choice. In all three neonates, ultrasonography showed complex abdominopelvic cysts indicating the need for surgery. In five of 10 episodes in older patients, ultrasonography showed a solid mass with an appearance strongly suggestive of torsion. Same-day surgery was performed in three patients, and the involved ovary was salvaged in one. Another patient had a small piece of normal-appearing ovary left in situ. This low rate of ovarian salvage is attributable to the combination of delay in patient presentation and surgical delay owing to the often nonspecific clinical and imaging presentation of ovarian torsion. A high level of clinical suspicion, expeditious imaging, and familiarity with the varied clinical and imaging presentations of ovarian torsion should decrease the surgical delay and improve the likelihood of ovarian salvage.