Cystic fibrosis diagnosed in late pregnancy.
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Biomedical subjects
Publications and source records attributed to A M Wright.
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Airway hyperresponsiveness induced by adenosine-5'-monophosphate (AMP) is regarded as a reliable model for allergic asthma and for the evaluation of anti-asthmatic drugs. Single-dose inhaled corticosteroids (ICS) are known to be protective in this model, but the duration of action of these drugs in this model has never been studied. The duration of ICS protection was determined by administration of single-dose fluticasone propionate (FP; 1,000 micrograms) up to 26 h before AMP challenge. A randomised, double-blind, placebo-controlled, four-way crossover study was performed in 13 mild asthmatics (mean +/- SD predicted forced expiratory volume in one second (FEV1) 98 +/- 7%). Each subject received placebo and FP (at 26, 14 or 2 h prior to the AMP challenge). Furthermore, the marker exhaled nitric oxide (eNO) was studied after administration at these time points to investigate whether eNO also demonstrates the duration of action of ICS. The doubling concentrations difference (DCD) of AMP causing a 20% fall in FEV1, when FP was administered 26, 14 or 2 h prior to challenge, was significantly increased as compared with placebo: DCD (95% confidence interval) at 26 h, 0.73 (0.20-1.26), p = 0.008; 14 h, 1.50 (0.99-2.01), p < 0.001; and 2 h, 2.89 (2.37-3.40), p < 0.001. However, eNO was not significantly affected at these time points. In conclusion, a single dose of 1,000 micrograms inhaled fluticasone propionate protects against adenosine-5'-monophosphate airway hyperresponsiveness up to 26 h after dosing. This study suggests that adenosine-5'-monophosphate challenge can be used as a sensitive marker to study the duration of action of inhaled corticosteroids.
We evaluated the effectiveness, ease of use and safety of five machines for blood salvage during coronary artery surgery. All were equally effective in concentrating red cells. We measured haemoglobin, packed cell volume, free haemoglobin, white cells, neutrophil elastase, platelets, thrombin-antithrombin complex (TAT), prothrombin activation peptide F1.2, fibrin degradation product (d-dimers), tissue plasminogen activator (tPA) and heparin in wound blood, in washed cell suspensions and in a unit of bank blood prepared for each patient. All machines were equally safe and easy to use and were equally effective in removing heparin and the physiological components measured. There were no adverse effects on patients. Clotting factors are severely depleted both in salvaged blood, even before washing, and in bank blood. Cell savers are a valuable adjunct to coronary artery surgery, but careful monitoring of coagulation is required when the volumes of either bank blood or salvaged blood are large.
In leukemic cells exposed to 2-chlorodeoxyadenosine (2-CdA), levels of the nucleoside drug and its phosphate metabolites decay with time in the absence of external 2-CdA; an intrinsic part of this process is the efflux of 2-CdA. The effects of nitrobenzylthioinosine (NBMPR) and of dipyridamole (DPM), both potent inhibitors of es (e, equilibrative; s, sensitive to NBMPR) nucleoside transport processes, were studied in four lines of cultured leukemic lymphoblasts. Suspensions of 2-CdA-loaded cells were diluted 10-fold with 2-CdA-free medium to initiate the cellular 2-CdA decay processes, which followed a biexponential time course. When diluting media contained NBMPR or DPM, intracellular levels of 2-CdA and its metabolites were substantially increased (P < 0.001) compared with cells in media lacking the transport inhibitors, and 2-CdA loss followed a monoexponential time course. As a consequence, the AUCs (area under time-course plots of intracellular 2-CdA and its metabolites) were significantly (P < 0.001) lower in untreated control cells compared to inhibitor-treated cells. These results suggest that nucleoside transport processes contribute to the efflux of 2-CdA from the cultured lymphoblasts. The cytotoxicity of 1-h exposure to 2-CdA of Reh-A2 and CCRF-CEM cells was enhanced three-fold by subsequent exposure to 0.5 microM NBMPR relative to that of control cells subjected to the same manipulations without NBMPR exposure. However, before such a strategy may be considered to have a therapeutic application, careful examination of effects in normal lymphocytes and ex vivo leukemic lymphoblasts must first be undertaken. Leukemia (2000) 14, 52-60.
STUDY DESIGN: The authors assessed degenerative lumbar displacement in a population-based cohort of 217 men and 400 women who had lateral lumbar radiographs performed at the mean age of 54 years and again at 79 years, and who had completed interviews on back symptoms and functional performance in connection with the follow-up examination. OBJECTIVES: To assess the prevalence and incidence of degenerative slippage and its association with back pain and physical disability. SUMMARY OF BACKGROUND DATA: Degenerative displacement of lumbar vertebrae may cause instability, nerve root compression, and spinal stenosis. Its incidence in the older population and association with back pain and disability are unknown. METHODS: The authors assessed the prevalence and incidence of degenerative slippage from lateral lumbar radiographs performed 25 years apart and its association with back pain and physical disability from interviews performed in connection with the follow-up examination. RESULTS: At the follow-up examination, 23 (12%) men and 100 (25%) women had developed degenerative slippage exceeding 3 mm; two of them had this already at the baseline. A forward displacement was found in 8 men and 76 women (P < 0.0001 for difference between the genders) and a backward one in 16 men and 35 women. On average, forward slip was 18% +/- 5.5, and backward slip, 15% +/- 4.0 of the anteroposterior diameter of the vertebra below. At the time of the second lumbar radiograph, 39 (32%) of the subjects with slippage, compared with 90 (19%) of the controls, had pain, aching, or stiffness in their back on most days (P = 0.001). After adjustment for endplate sclerosis, which was also related to pain (P = 0.015), slippage still had association with daily back symptoms (P = 0.009). However, subjects with slippage had not experienced more back symptoms during the preceding year or in earlier ages of life, and they did not report more disability than the controls. CONCLUSIONS: Degenerative displacement of lumbar vertebrae is common in an older population and is associated with increased prevalence of daily back symptoms. However, two thirds of the subjects with degenerative displacement do not report ongoing back symptoms, and the disorder is also unrelated to long-term back pain and physical disability.
This research explored the effects of haloperidol (HP) metabolites on biogenic amine uptake and release, and compared them to those of MPTP and its toxic metabolite, MPP+. In synaptosome preparations from mouse striatum and cortex, the HP metabolites haloperidol pyridinium (HPP+), reduced haloperidol pyridinium (RHPP+), and haloperidol tetrahydropyridine (HPTP) inhibited the presynaptic uptake of dopamine and serotonin, with greater affinity for the serotonin transporter. HPP+ was the most potent inhibitor of dopamine uptake, and HPTP of serotonin uptake, both with IC50 values in the low micromolar range. RHPP+ was less active than the other metabolites, but was more active than the parent compound, HP. Inhibition of uptake was reversed when free drug was removed by centrifugation and then resuspension of the synaptosomes in fresh buffer, suggesting that inhibition of uptake was due to interaction with the transporters and was not due to irreversible cytotoxicity. HPP+ showed noncompetitive inhibition of both serotonin and dopamine uptake, suggesting that it has a relatively slow dissociation rate for its interaction with the transporter proteins. In experiments on amine release, HPP+ and HPTP were four-fold less potent than MPP+ for releasing preloaded dopamine from striatal synaptosomes, and only MPP+-dependent release was antagonized by the uptake blocker, mazindol. In contrast, RHPP+ displayed little ability to release either amine neurotransmitter. HPTP was about two-fold more potent than MPP+ for releasing serotonin from cortical synaptosomes, whereas HPP+ was less active than MPP+. The specific serotonin transport blocker fluoxetine was only able to antagonize release induced by MPP+. These results suggest that HP metabolites bind to the transporters for dopamine and serotonin, but are not transporter substrates. In contrast to their potent effects on amine release, HPP+ and HPTP were unable to release preloaded GABA from cortical synaptosomes. The implications of these results concerning a possible role of HP metabolites in the development of tardive dyskinesia are discussed.
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Spatial learning in old mice (19 or 24 months old), some of which had been calorically restricted beginning at 14 weeks of age, was compared to that of young mice, in two separate experiments using a Morris water maze. In the first experiment, only old mice reaching criterion performance on a cued learning task were tested in a subsequent spatial task. Thus, all old mice tested for spatial learning had achieved escape latencies equivalent to those of young controls. Despite equivalent swimming speeds, only about half the old mice in each diet group achieved criterion performance in the spatial task. In the second experiment, old and young mice all received the same number of training trials in a cued task and then in a spatial task. Immediately following spatial training, they were given a 60-s probe trial, with no platform in the pool. Both groups of old mice spent significantly less time in the quadrant where the platform had been and made significantly fewer direct crosses over the previous platform location than did the young control group. As in Experiment 1, calorie restriction failed to provide protection against aging-related deficits. However, in both experiments, some individual old mice evidenced performance in spatial learning indistinguishable from that of young controls. Separate comparisons of "age-impaired" and "age-unimpaired" old mice with young controls may facilitate the identification of neurobiological mechanisms underlying age-related cognitive decline.
Five strains of Bacillus stearothermophilus have been studied to identify a spore strain to be used as a biological indicator organism for low temperature steam and formaldehyde sterilization. Three strains gave poor reproducibility of batch size and growth index and were discarded. The other two strains gave good reproducibility with a high growth index and gave rise to linear survivor curves when exposed to 5% aqueous formaldehyde. However, only NCIMB 8224 sporulates on a simpler medium and as it was the most resistant to formaldehyde, it was further studied. Tests were carried out in a modified miniclave and factors studied included temperature of the steam and formaldehyde concentration. All studies confirmed the suitability of this strain as a biological indicator organism.
Preliminary screening was carried out on spores of 29 strains of Bacillus stearothermophilus to determine their potential as biological indicator organisms for low temperature steam and formaldehyde sterilization. Each strain was sporulated on four chemically defined media. Fourteen strains produced satisfactory sporulation on one or more of the media but there was considerable variation in the extent of sporulation. The growth index of the spores, which was dependent on both the strain of organism and the sporulation medium, ranged from 1% to 90%. The spores were appraised on the basis of their resistance to inactivation by 0.5% w/v formaldehyde in aqueous solution at 70 degrees C. The survivor curves obtained could be characterized into five types on the basis of the shape of the curve. Only five strains of Bacillus stearothermophilus produced spores with the characteristics of high resistance, linear semi-logarithmic survivor curve and high growth index that would be required of a potential biological indicator organism.
Fluorescence microscopy shows extensive filling of perikarya and distal dendrites following injections of Fluoro-Gold (FG) into their terminal fields. However, elucidation of synaptic contacts onto identified projection neurons has been limited by the lack of compatibility between electron-dense markers required for ultrastructural analysis and morphology preservation. The recent advent of antisera to FG has revealed numerous potential applications for analyzing chemically defined synaptic circuitry. To take advantage of the high sensitivity of this retrograde tracer in ultrastructural studies, we extended and detailed the original description of single immunocytochemical labeling of FG by comparing the advantages of immunodetection of an antiserum against FG using 2 distinct electron-dense markers: (1) avidin-biotin peroxidase (ABC) reacted with 3,3'-diaminobenzidine and darkened with osmium tetroxide, or (2) silver-intensified 1 nm colloidal gold particles. We subsequently examined the utility of combining these markers in single sections for detection of transmitters (e.g., gamma-aminobutyric acid (GABA) and 5-hydroxytryptamine (5-HT)) in axon terminals presynaptic to retrogradely labeled neurons. Both analyses were carried out on the well-characterized mesolimbic pathway originating from perikarya in the ventral tegmental area (VTA) that project to the nucleus accumbens. Injections of FG were stereotaxically placed in the nucleus accumbens of anesthetized adult rats. From these animals, vibratome sections of aldehyde-fixed brains were examined for light-microscopic detection of FG using: (1) epi-fluorescence without immunocytochemistry, (2) immunoperoxidase, or (3) immunogold-silver. All 3 methods revealed circumscribed injections in the nucleus accumbens. Additionally, both immunocytochemical methods appeared to be as sensitive as epi-fluorescence in light-microscopic detection of retrogradely labeled perikarya and fine-caliber dendrites extending for 2-3 branch points beyond the soma. Electron microscopy showed that the FG was detectable not only in lysosomes but also throughout the cytoplasmic matrix of perikarya and dendrites using either immunoperoxidase or immunogold-silver labeling methods. In the second part of this analysis, single sections of tissue were processed for dual labeling using either immunoperoxidase or immunogold-silver for detection of FG in conjunction with the converse label for GABA or 5-HT, respectively. Regardless of the labeling combinations, the peroxidase and gold-silver reactions were readily distinguished within sections examined by light or electron microscopy. Synaptic junctions from unlabeled or from GABA or 5-HT labeled terminals were most readily identified when the targets were lightly immunoreactive for peroxidase or labeled using silver-intensified colloidal gold.(ABSTRACT TRUNCATED AT 400 WORDS)
Postoperative duplex scans were performed on 185 patients undergoing posterior lumbar spinal surgery in order to identify deep venous thrombosis (DVT). Elastic compression stockings were used for prophylaxis in 74 patients (Group E.S.); intermittent pneumatic compression was used in the remaining 111 patients (Group P.C.). High-risk patients were not eliminated from either group. Laminectomy was performed on 84 patients (40 from Group E.S. and 44 from Group P.C.), and spinal fusion, on 101 patients (34 from Group E.S. and 67 from Group P.C.). A total of four patients, all from Group E.S., developed acute postoperative DVT. Intermittent pneumatic compression significantly reduced the incidence of acute postoperative DVT (P < 0.05). No statistically significant differences were found in the incidence of DVT in relation to the type of spinal procedure, length of procedure, duration of bed rest, or age of the patient. In conclusion, considering the low rate of DVT (2%) following posterior lumbar surgery and the potential complications of prophylactic anticoagulation, we continue to use intermittent pneumatic compression rather than elastic stockings for prophylaxis.
Forty patients with karyotypically proven Turner syndrome were prospectively studied using magnetic resonance imaging (MRI) and echocardiography in order to determine the frequency of cardiovascular anomalies and to assess the utility of both imaging modalities as methods for cardiovascular evaluation in Turner syndrome. Cardiovascular anomalies were found in 45% of patients. A high absolute prevalence of bicuspid aortic valve (17.5%) and aortic coarctation (12.5%) were observed relative to comparable series. Of clinically significant abnormalities, three of five aortic coarctations and four of five ascending aortic dilatations were solely MRI detected and not evident at echocardiographic examination. MRI is thus seen as a valuable adjunct to echocardiography in the cardiovascular evaluation of Turner syndrome patients. The usefulness of MRI primarily relates to its ability to provide excellent visualisation of the entire thoracic aorta where a large proportion of clinically significant anomalies occur in Turner syndrome.
The authors describe a technique for removing or repositioning a malpositioned Greenfield inferior vena caval filter. A "monorail" system was used, in which a wire was passed from the femoral vein through the apical hole in the filter and out the internal jugular vein; the wire was held taut from above and below and thus facilitated repositioning or removal of the filter. The technique was used successfully in two cases.
We studied the effect of aminophylline on twitch tension (TT) and intracellular pH (pHi) in isolated rat diaphragm strips that were fatigued, hypercapnic, or hypoxic. Superfused muscles were directly stimulated at 0.5 Hz. The pHi was measured from distribution volumes of dimethyl-oxazolidinedione. Fatigue was induced by intermittent tetanic stimulation. Hypercapnia and hypoxia were produced by altering superfusate carbon dioxide tension (PCO2) or oxygen tension (PO2). Aminophylline (1.0 mmol.l-1) reversed the twitch decay seen during fatigue or hypercapnic acidosis, and caused partial recovery of twitch depression during hypoxia. Muscle fatigue was not due to an intracellular acidosis. Both hypercapnia and hypoxia lowered pHi. Aminophylline did not alter pHi in unstimulated muscles, but caused a significant fall in pHi in stimulated muscles that were fatigued or hypoxic. High dose aminophylline improved twitch tension in diaphragm strips that were fatigued, acidotic, or hypoxic. Twitch potentiation was not due to an intracellular alkalosis. Aminophylline lowered pHi in stimulated muscle, and thus, theoretically, could sometimes be harmful in the treatment of muscle fatigue.
Five young children (mean age 26.4 months) with angiolymphoid hyperplasia with eosinophilia (Kimura's disease) from either the upper arm or buttock were identified over 18 months. The unusual distribution of the lesions and the young age of the patients suggested a possible association with immunisation. The clinical and histopathological features in these cases were accordingly reviewed. The biopsy specimens showed the usual histological appearances of a prominent inflammatory component, fibrosis, and vascular proliferation associated with aggregates of eosinophils. The features were those of a reactive rather than neoplastic process. Immunohistochemical preparations showed positive staining of variable numbers of plasma cells with antibodies to IgG, IgM, IgA and IgE and a reticular staining of germinal centres with IgM and IgE antibodies. Immunisation histories obtained from the patients' general practitioners showed a remarkable correlation between the distribution of the lesions and the sites of injections and an aetiological role for immunisation in these cases seems likely.
A method has been developed to increase the probability of success of percutaneous transluminal balloon angioplasty of total occlusions of the common iliac artery when conventional methods have failed. In 10 patients with a totally obstructed iliac artery, a guide wire was passed through a catheter placed from the contralateral side around the aortic bifurcation and antegrade through the total obstruction. The end of the wire was either snared by a retrieval basket or guided through a sheath in the ipsilateral common femoral artery, thus providing a firmly anchored pathway for subsequent manipulations. Balloons were then inserted retrograde through both common femoral arteries and dilated. In the first five patients, ipsilateral retrograde passage of a guide wire had failed despite multiple attempts with a variety of devices. In the other five patients, the contralateral antegrade approach was used initially. The new method was successful in all 10 patients with totally obstructed common iliac arteries.