Fracture of the sternum in children.

OBJECTIVE: Sternal fracture is poorly characterised in children. The purpose of this study was to gain insight into the mechanism, radiological characteristics, and accompanying injuries of sternal fracture in children. METHODS: The study was retrospective. The records of all children who underwent plain radiography of the sternum, or computed tomography of the thorax after trauma, over a 40 month period in our paediatric hospital were reviewed for evidence of sternal fracture. RESULTS: 12 of 33 children identified had radiological evidence of sternal fracture. The age range of children with fractures was 5 to 12 years. Eleven children had fracture of the anterior cortex of the first or second sternebra of the body of the sternum. One child had fracture through the manubriosternal joint with posterior displacement of the body. Seven fractures resulted from direct blows to the anterior chest, five fractures resulted from hyperflexion injury of the thoracic spine. None were the result of motor vehicle crash. All fractures were isolated injuries. CONCLUSIONS: Sternal fracture is uncommon in children. Injury may result from direct or indirect violence. The child's sternum is commonly fractured by more minor blunt trauma than generally recognised in the literature. All patients with sternal fracture after indirect violence should have careful examination of the spine. Patients with undisplaced anterior cortical fracture without other injury may be safely discharged from the emergency department.

Use of analgesia in a paediatric accident and emergency department following limb trauma.

The objective of this study was to assess analgesic use and the use of a pain scoring system on those children presenting to a paediatric accident and emergency (A&E) department with a history of injury due to trauma. A random sample of patients who presented to a paediatric A&E department over a 6-week period with a history of limb trauma were prospectively studied. Pain severity scores were assessed on arrival and at 10, 30 and 60 minutes using the Douhit Faces Scale and any analgesia given or plaster application was noted. One hundred and seventy-two patients were studied. The median age was 10 years (range 3-13 years) and the majority, 56%, were male. The mean initial pain scores were 2.7 (range 1-4) for boys and 3.0 (range 1-4) for girls. The presenting injuries were 103 upper or lower limb fractures and 69 'soft tissue' injuries. Only 84 (49%) patients received analgesic medication in the department (30% morphine; 70% paracetamol); analgesia was not given to the remaining 88 (51%). Of these, 7 declined analgesia, and 5 had already taken analgesia on arrival to A&E. Despite prompt triage (median time 2 minutes, range 0-10 minutes), the median time from arrival to paracetamol administration was 20 minutes (range 4-105 minutes) and for morphine was 14 minutes (range 2-57 minutes). Pain is a common symptom in patients presenting to A&E. Because children's pain can be particularly difficult to assess, a pain scoring system such as the Douhit Faces Scale can be a useful means of pain assessment in the A&E setting. Despite increased awareness, pain is still under treated in the A&E department.

Properties of dissimilatory nitrate reductase purified from the denitrifier Pseudomonas aeruginosa.

Dissimilatory nitrate reductase was purified to homogeneity from anaerobic cultures of the denitrifying bacterium Pseudomonas aeruginosa. The following procedures were used in the rapid isolation of this unstable enzyme: induction by nitrate in semianaerobic cell suspension, heat-stimulated activation and solubilization from the membrane fraction, and purification by hydrophobic interaction chromatography. The molecular weight of the purified enzyme was estimated by nondenaturing polyacrylamide gel electrophoresis, sucrose density gradient sedimentation, and gel filtration chromatography. Subunit molecular weights were estimated by electrophoresis in sodium dodecyl sulfate-polyacrylamide gels. The active enzyme monomer, with a molecular weight of 176,000 to 260,000 (depending upon the method of determination), was composed of subunits with molecular weights of approximately 64,000 and 118,000. The monomer aggregated to form an inactive tetramer of about 800,000 molecular weight. Purified enzyme exhibited a broad pH optimum, between 6.5 and 7.5. Kinetic studies showed that the apparent Km was 0.30 mM for nitrate, and 2.2 to 2.9 microM for dithionite-reduced benzyl viologen. Azide was an effective inhibitor: the concentration required for half-maximal inhibition was 21 to 24 microM. Azide inhibition was competitive with nitrate (Ki = 2.0 microM) but uncompetitive with reduced benzyl viologen (Ki = 25 microM). Based upon spectral evidence, the purified molybdo-enzyme had no associated cytochromes but did contain nonhaem iron that responded to dithionite reduction and nitrate oxidation. The enzyme that was purified after being heat solubilized from membranes had properties essentially identical to those of the enzyme that was purified after deoxycholate solubilization.