Adhesive lesions of the talocrural joint

Iatrogenic and posttraumatic adhesive lesions of the ankle joint are rather common, although infrequently reported, clinical entities. Ankle arthroscopy has proved to be a valuable asset in the assessment and treatment of recalcitrant symptomatic cases of both localized adhesions and adhesive capsulitis. This article intends to broaden the reader's understanding of the clinical presentation and intra-articular derangements of these lesions.     

Seizure disorders in burned children: a retrospective review

This review shows that hyponatremia is the most common cause of burn seizures in children, followed by a history of epilepsy, hypoxia, sepsis with high fever, unknown aetiology and drug toxicity or sudden drug withdrawal. This study also shows that burn seizure is most common in younger children and is related to size and degree of burn. We recommend close monitoring of metabolism, haemodynamics, arterial blood gases, wound and blood cultures, and levels of abnormalities in serum, electrolytes, glucose, Ca, P and Mg. Prompt corrections of any problems in these areas can be vital. Invasive procedures for the diagnosis of seizures, including lumbar puncture and EEG, should be reserved for infrequent non-responding cases.     

Effect of niflumic acid on noradrenaline-induced contractions of the rat aorta

1. The effects of niflumic acid, an inhibitor of calcium-activated chloride channels, were compared with the actions of the calcium channel antagonist nifedipine on noradrenaline-evoked contractions in isolated preparations of the rat aorta. 2. The cumulative concentration-effect curve to noradrenaline (NA) was depressed by both nifedipine and niflumic acid in a reversible and concentration-dependent manner. The degree of inhibition of the maximal contractile response to NA (1 microM) produced by 10 microM niflumic acid (38%) was similar to the effect of 1 microM nifedipine (39%). 3. Contractions to brief applications (30 s) of 1 microM NA were inhibited by 55% and 62% respectively by 10 microM niflumic acid and 1 microM nifedipine. 4. In the presence of 0.1 microM nifedipine, niflumic acid (10 microM) produced no further inhibition of the NA-evoked contractions. Thus, the actions of niflumic acid and nifedipine were not additive. 5. In Ca-free conditions the transient contraction induced by 1 microM NA was not inhibited by niflumic acid (10 microM) and therefore this agent does not reduce the amount of calcium released from the intracellular store or reduce the sensitivity of the contractile apparatus to calcium. 6. Niflumic acid 10 microM did not inhibit the contractions produced by KCl (up to 120 mM) which were totally blocked by nifedipine. Contractions induced by 25 mM KCl were completely inhibited by 1 microM levcromakalim but were unaffected by niflumic acid. 7. It was concluded that niflumic acid produces selective inhibition of a component of NA-evoked contraction which is probably mediated by voltage-gated calcium channels. These data are consistent with a model in which NA stimulates a calcium-activated chloride conductance which leads to the opening of voltage-gated calcium channels to produce contraction.     

Band 3 protein: structure, flexibility and function

The oxidation of antibody carbohydrate residues is a common approach used for site-specific antibody immobilization or modification. In this study a flow injection analysis system (FIA) was developed for monitoring antibody oxidation. Antibodies were oxidized with periodate and the resulting aldehyde groups were labeled with Lucifer yellow CH (LyCH). The labeled antibodies were then injected onto an FIA system where the amount of LyCH label was determined by absorbance measurements at 428 nm and the amount of antibody was determined using an on-line bicinchoninic acid protein assay. The analysis time was 2 min per 20 microliters sample injection. The limits of detection for rabbit immunoglobulin G (IgG) and LyCH were 1 x 10(-8) and 4 x 10(-7) M, respectively. The dynamic ranges for IgG and LyCH extended to 2 x 10(-5) and 7 x 10(-3) M. The within-run precision was +/- 5% or less for both analytes. Studies with known LyCH/antibody mixtures indicated that the FIA system had greater accuracy than manual methods at high LyCH levels. One specific application studied for this system was its use in monitoring the time course of periodate-antibody oxidation.     

Increased recruitment of hematopoietic progenitor cells underlies the ex vivo expansion potential of FLT3 ligand

The ligand for flt-3 (FLT3L) exhibits striking structural homology with stem cell factor (SCF) and monocyte colony-stimulating factor (M-CSF) and also acts in synergy with a range of other hematopoietic growth factors (HGF). In this study, we show that FLT3L responsive hematopoietic progenitor cells (HPC) are CD34+CD38-, rhodamine 123dull, and hydroperoxycyclophosphamide (4-HC) resistant. To investigate the basis for the capacity of FLT3L to augment the de novo generation of myeloid progenitors from CD34+CD38- cells, single bone marrow CD34+CD38- cells were sorted into Terasaki wells containing serum-free medium supplemented with interleukin-3 (IL-3), IL-6, granulocyte colony-stimulating factor (G-CSF), SCF (4 HGF) +/- FLT3L. Under these conditions, FLT3L recruited approximately twofold more CD34+CD38- cells into division than 4 HGF alone. The enhanced proliferative response to FLT3L was evident by day 3 and was maintained at all subsequent time points examined. In accord with these findings, we also show that transduction of CD34+CD38- cells with the LAPSN retrovirus is enhanced by FLT3L. The results of these experiments therefore indicate that increased recruitment of primitive HPC into cell cycle underlies the ex vivo expansion potential of FLT3L and also its ability to improve retroviral transduction of HPC.     

Initiation of the phosphoinositide cycle by parathyroid hormone in synaptosomes

We studied the effects of parathyroid hormone 10(-9) M) on the contents of mono-, di-, and triglycerides, total phospholipids, and free arachidonic acid in rat brain cortex synaptosomes using [1-(14)C]arachidonic acid at 2, 5, and 10 sec after addition of the hormone. Our data demonstrated the changes in lipid metabolism in synaptosomal membranes which were especially pronounced at 5 sec after addition of parathyroid hormone. Incorporation of 70% of [1-(14)C]arachidonic acid into the phosphoinositide fraction and the progress of changes in lipid metabolite composition suggest that the phosphoinositide cycle is initiated by parathyroid hormone, and the hormonal signal may be subsequently mediated in nerve cells by 1,2-diacylglycerol, a product of the phosphoinositide cycle.     

Morphological differentiation and nitrogen fixation in transposon generated mutants of Anabaena 7120

Mutants having partially repressed glutamine sythetase (transferase) activity and high nitrogenase activity were isolated following transposon mutagenesis. Two of these mutants M11 and M73 showed a decrease in heterocyst frequency compared with the wild type strain. The level of the enzyme nitrogenase was much higher in all the mutant strains. Nitrate and ammonia completely suppressed heterocyst differentiation and nitrogenase activity in mutants M11 and M73, but mutant M55 differentiated heterocysts and showed nitrogenase activity even in the presence of these combined inorganic nitrogen sources. Heterocyst frequency in the M55 mutant was much more than that of the wild strain. Glutamine as a nitrogen source completely suppressed differentiation of heterocysts as well as nitrogenase activity, irrespective of the presence or absence of the glutamate analogue MSX which relieved the inhibitory effect of nitrate or ammonia on heterocyst differentiation and nitrogenase activity. The level of the intracellular ammonium pool was maximal in the wild strain in all the nitrogen sources used for growth. Cultures raised with ammonium chloride gave maximum values for intracellular ammonium pool in all the mutant strains and the wild strain. Mutants showed about 55 to 60% less GS (transferase) activity than the wild strain.     

Regional audit of pedestrian accident care

In all, 160 serious pedestrian accidents (ISS > 15 or death), were recorded during a 12-month prospective study of all trauma in a population of 3.2 million. Of these, 35 died at scene, 125 arrived at hospital alive and 68 (54 per cent) subsequently died. There were 35 (22 per cent) children, and 62 per cent (39) were more than 60 years of age. Prehospital care significantly delayed transfer to hospital. In the accident and emergency department, only 38 per cent of those unconscious had a cervical collar applied, and only 67 per cent were intubated. Of those transferred for neurosurgical care, 34 per cent were not intubated. The Median Injury Severity Score for each outcome group was similar between age groups. The Revised Trauma Score and APACHE II score showed significant differences between those who lived and died. TRISS analysis revealed that 32 per cent of deaths and 12 per cent of survivors were unexpected. ATLS treatment protocols should be instituted for prehospital care and in all accident and emergency departments (A&E).