Cannabidivarin is anticonvulsant in mouse and rat

BACKGROUND AND PURPOSE

Phytocannabinoids in Cannabis sativa have diverse pharmacological targets extending beyond cannabinoid receptors and several exert notable anticonvulsant effects. For the first time, we investigated the anticonvulsant profile of the phytocannabinoid cannabidivarin (CBDV) in vitro and in in vivo seizure models.

EXPERIMENTAL APPROACH

The effect of CBDV (1-100 μM) on epileptiform local field potentials (LFPs) induced in rat hippocampal brain slices by 4-aminopyridine (4-AP) application or Mg(2+) -free conditions was assessed by in vitro multi-electrode array recordings. Additionally, the anticonvulsant profile of CBDV (50-200 mg·kg(-1) ) in vivo was investigated in four rodent seizure models: maximal electroshock (mES) and audiogenic seizures in mice, and pentylenetetrazole (PTZ) and pilocarpine-induced seizures in rats. The effects of CBDV in combination with commonly used antiepileptic drugs on rat seizures were investigated. Finally, the motor side effect profile of CBDV was investigated using static beam and grip strength assays.

KEY RESULTS

CBDV significantly attenuated status epilepticus-like epileptiform LFPs induced by 4-AP and Mg(2+) -free conditions. CBDV had significant anticonvulsant effects on the mES (≥100 mg·kg(-1) ), audiogenic (≥50 mg·kg(-1) ) and PTZ-induced seizures (≥100 mg·kg(-1) ). CBDV (200 mg·kg(-1) ) alone had no effect against pilocarpine-induced seizures, but significantly attenuated these seizures when administered with valproate or phenobarbital at this dose. CBDV had no effect on motor function.

CONCLUSIONS AND IMPLICATIONS

These results indicate that CBDV is an effective anticonvulsant in a broad range of seizure models. Also it did not significantly affect normal motor function and, therefore, merits further investigation as a novel anti-epileptic in chronic epilepsy models.

LINKED ARTICLES

This article is part of a themed section on Cannabinoids. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2012.167.issue-8.

Stathmin is expressed by the proliferating hepatocytes during liver regeneration

Aim-To determine the liver cell populations that express the phylogenetically conserved cytosolic protein stathmin during liver regeneration.Methods-Double immunostaining for stathmin and the Ki67 antigen was performed on sections of formaldehyde fixed, paraffin wax embedded tissues from 31 liver specimens. These included a variety of disease conditions characterised by some degree of hepatocyte regeneration. Quantitative western blot analysis was performed on 22 of these specimens.Results-Variable amounts of stathmin protein were detected by western blotting in all of the specimens examined. Stathmin was not detected in three cases of histologically normal liver. On immunostaining, stathmin was demonstrated in a proportion of hepatocytes as well as lymphoid inflammatory cells and other tissue elements. In all cases most of these stathmin positive cells showed nuclear positivity for the Ki67 antigen.Conclusions-Stathmin is expressed by proliferating hepatocytes but not by resting hepatocytes. Thus, it is likely that the protein has a function important to cell proliferation as opposed to cell differentiation.

Kinetics of expansion of epitope-specific T cell responses during primary HIV-1 infection

Multiple lines of evidence support a role for CD8(+) T cells in control of acute/early HIV replication; however, features of the primary HIV-specific CD8(+) T cell response that may impact on the efficiency of containment of early viral replication remain poorly defined. In this study, we performed a novel, comprehensive analysis of the kinetics of expansion of components of the HIV-specific CD8(+) T cell response in 21 acutely infected individuals. Epitope-specific T cell responses expanded asynchronously during primary infection in all subjects. The most rapidly expanded responses peaked as early as 5 days following symptomatic presentation and were typically of very limited epitope breadth. Responses of additional specificities expanded and contracted in subsequent waves, resulting in successive shifts in the epitope immunodominance hierarchy over time. Sequence variation and escape were temporally associated with the decline in magnitude of only a subset of T cell responses, suggesting that other factors such as Ag load and T cell exhaustion may play a role in driving the contraction of HIV-specific T cell responses. These observations document the preferential expansion of CD8(+) T cells recognizing a subset of epitopes during the viral burst in acute HIV-1 infection and suggest that the nature of the initial, very rapidly expanded T cell response may influence the efficiency with which viral replication is contained in acute/early HIV infection.

Rapid onset intratubular calcification following renal transplantation requiring urgent parathyroidectomy

BACKGROUND

Secondary hyperparathyroidism is a common complication of end-stage renal disease often requiring parathyroidectomy. Renal transplant with the restoration of normal renal function often allows resolution of hyperparathyroidism, avoiding the need for parathyroid surgery. However, a proportion of patients with hyperparathyroidism become overtly hypercalcemic after renal transplantation which poses management dilemmas between medical and surgical treatment.

CASE

We present the case of a 48-yearold man with end-stage renal failure known to have secondary hyperparathyroidism who received a living related renal transplant. Postoperatively he developed prompt hypercalcemia, polyuria, polydipsia and rapid onset intratubular calcification, leading to acute tubular necrosis diagnosed on renal biopsy on Day 7 post transplantation. He underwent surgical parathyroidectomy with resolution of his hypercalcemia and improved renal transplant function.

DISCUSSION

This case emphasizes the need for good management of secondary hyperparathyroidism together with close surveillance of PTH in patients awaiting renal transplantation. With good renal transplant function hyperparathyroidism usually resolves. Posttransplant surgical parathyroidectomy should be reserved for severe progressive end organ damage.

HIV-1 epitope-specific CD8+ T cell responses strongly associated with delayed disease progression cross-recognize epitope variants efficiently

The ability of HIV-1-specific CD8(+) T cell responses to recognize epitope variants resulting from viral sequence variation in vivo may affect the ease with which HIV-1 can escape T cell control and impact on the rate of disease progression in HIV-1-infected humans. Here, we studied the functional cross-reactivity of CD8 responses to HIV-1 epitopes restricted by HLA class I alleles associated with differential prognosis of infection. We show that the epitope-specific responses exhibiting the most efficient cross-recognition of amino acid-substituted variants were those strongly associated with delayed progression to disease. Not all epitopes restricted by the same HLA class I allele showed similar variant cross-recognition efficiency, consistent with the hypothesis that the reported associations between particular HLA class I alleles and rate of disease progression may be due to the quality of responses to certain "critical" epitopes. Irrespective of their efficiency of functional cross-recognition, CD8(+) T cells of all HIV-1 epitope specificities examined showed focused TCR usage. Furthermore, interpatient variability in variant cross-reactivity correlated well with use of different dominant TCR Vbeta families, suggesting that flexibility is not conferred by the overall clonal breadth of the response but instead by properties of the dominant TCR(s) used for epitope recognition. A better understanding of the features of T cell responses associated with long-term control of viral replication should facilitate rational vaccine design.

Phosphodiesterase (PDE) 7 in inflammatory cells from patients with asthma and COPD

In inflammatory cells, the low K(m) cyclic adenosine monophosphate (cAMP)-specific phosphodiesterase (PDE) 4 subtype is predominant in terms of expression and function, although more recently it has been suggested that PDE 7 may also play a role in regulating inflammatory cell activity. In the present study, PDE 4 and PDE 7 subtype messenger ribonucleic acid (mRNA) transcripts in CD4 and CD8 lymphocytes from healthy (n=10) and asthmatic (n=10) subjects and polymorphonuclear neutrophils (PMNs) and CD8 lymphocytes obtained from healthy (n=10) and chronic obstructive pulmonary disease (COPD) (n=7) subjects were identified and quantified. PDE 4A, PDE 4B, PDE 4D and PDE 7A mRNA were present in similar quantities in both CD4 and CD8 lymphocytes obtained from healthy and asthmatic subjects and in CD8 lymphocytes obtained from healthy and COPD subjects. Expression of PDE 4C and PDE 7B mRNA was also observed, although transcript levels were low and variable between individuals. In addition, the effects of selective PDE 7 inhibition on both phytohaemagluttinin (PHA)-induced human peripheral blood mixed mononuclear cell (HPBMNC) proliferation and fMLP-induced neutrophil elastase (NE) release were studied. HPBMNC and human neutrophils, isolated from the venous blood of healthy volunteers (n=6) were treated with either a novel selective PDE 7 inhibitor PF 0332040 alone or in combination with rolipram. Proliferation of HPBMNC was stimulated by PHA (2microgml(-1)) and assessed by [(3)H]-thymidine incorporation, while fMLP-induced (100nM) NE release was determined using a chromogenic substrate. Both rolipram (0.003-10microM) and PF 0332040 (0.003-10microM) significantly inhibited PHA-stimulated proliferation of HPBMNC ((**)P<0.01). Co-administration of rolipram (0.3-10microM) and PF 0332040 (0.003-10microM) significantly increased the degree of inhibition observed, compared to when either drug was administered alone ((**)P<0.01). PF 0332040 (0.003-10microM) had no inhibitory effect on NE release from human peripheral blood neutrophils stimulated with fMLP (100nM), while rolipram (0.003-10microM) significantly inhibited neutrophil degranulation ((**)P<0.01). These findings suggest no evidence of altered PDE 4 or PDE 7 mRNA transcript levels in inflammatory cells isolated from the peripheral venous blood of mild asymptomatic asthmatic subjects or stable COPD subjects, however, inhibition of PDE 7 may influence mononuclear cell function.

Detection of antibody-dependent complement-mediated inactivation of both autologous and heterologous virus in primary human immunodeficiency virus type 1 infection

Specific CD8 T-cell responses to human immunodeficiency virus type 1 (HIV-1) are induced in primary infection and make an important contribution to the control of early viral replication. The importance of neutralizing antibodies in containing primary viremia is questioned because they usually arise much later. Nevertheless antienvelope antibodies develop simultaneously with, or even before, peak viremia. We determined whether such antibodies might control viremia by complement-mediated inactivation (CMI). In each of seven patients studied, antibodies capable of CMI appeared at or shortly after the peak in viremia, concomitantly with detection of virus-specific T-cell responses. The CMI was effective on both autologous and heterologous HIV-1 isolates. Activation of the classical pathway and direct viral lysis were at least partly responsible. Since immunoglobulin G (IgG)-antibodies triggered the CMI, specific memory B cells could also be induced by vaccination. Thus, consideration should be given to vaccination strategies that induce IgG antibodies capable of CMI.

Determinants of human immunodeficiency virus type 1 escape from the primary CD8+ cytotoxic T lymphocyte response

CD8⁺ cytotoxic T lymphocytes (CTLs) play an important role in containment of virus replication in primary human immunodeficiency virus (HIV) infection. HIV's ability to mutate to escape from CTL pressure is increasingly recognized; but comprehensive studies of escape from the CD8 T cell response in primary HIV infection are currently lacking. Here, we have fully characterized the primary CTL response to autologous virus Env, Gag, and Tat proteins in three patients, and investigated the extent, kinetics, and mechanisms of viral escape from epitope-specific components of the response. In all three individuals, we observed variation beginning within weeks of infection at epitope-containing sites in the viral quasispecies, which conferred escape by mechanisms including altered peptide presentation/recognition and altered antigen processing. The number of epitope-containing regions exhibiting evidence of early CTL escape ranged from 1 out of 21 in a subject who controlled viral replication effectively to 5 out of 7 in a subject who did not. Evaluation of the extent and kinetics of HIV-1 escape from >40 different epitope-specific CD8 T cell responses enabled analysis of factors determining escape and suggested that escape is restricted by costs to intrinsic viral fitness and by broad, codominant distribution of CTL-mediated pressure on viral replication.

The effect of selective phosphodiesterase isoenzyme inhibition on neutrophil function in vitro

Neutrophil-derived proteases such as neutrophil elastase (NE) and matrix metalloproteinase (MMP) are implicated in the pathogenesis of Chronic Obstructive Pulmonary Disease (COPD). In this study, the effects of selective phosphodiesterase (PDE) inhibition on NE and MMP-9 release, as well as Myeloperoxidase (MPO) activity and integrin-mediated neutrophil adhesion to human umbilical vein endothelial cells (HUVECs), were investigated. Human neutrophils were treated with PDE inhibitors (10(-11)-10(-4)M) in the absence and presence of TNF-alpha (tumour necrosis factor) (100 U ml(-1)) for 30 min, prior to fMLP activation. After 45 min, the cells were removed and NE, MPO and MMP-9 release assessed. In the adhesion studies, the neutrophils were radio-labelled with 51Cr, stimulated and immediately transferred to cultured HUVEC monolayers for 30 min, prior to assessment of adhesion. TNF-alpha (100 U ml(-1)) acted synergistically with fMLP in stimulating azurophil degranulation with respect to both MPO activity (P<0.01) and NE release (P<0.01). In contrast, an additive effect was observed with TNF-alpha and fMLP with regard to MMP-9 release and neutrophil adhesion to HUVECs. The PDE4 inhibitors, roflumilast, roflumilast N-oxide, cilomilast and rolipram significantly suppressed MPO, NE and MMP-9 release in both the presence and absence of TNF-alpha (P<0.05; n=6-10) and also reduced neutrophil adhesion to HUVECs. In contrast, milrinone, a PDE3 inhibitor and the non-selective PDE inhibitor, theophylline did not inhibit azurophil degranulation under any of the experimental conditions. These data provide further evidence that selective PDE4 isoenzyme inhibitors can inhibit neutrophil degranulation, effects not shared by PDE3 inhibitors or theophylline.

Coupling in silico and in vitro analysis of peptide-MHC binding: a bioinformatic approach enabling prediction of superbinding peptides and anchorless epitopes

The ability to define and manipulate the interaction of peptides with MHC molecules has immense immunological utility, with applications in epitope identification, vaccine design, and immunomodulation. However, the methods currently available for prediction of peptide-MHC binding are far from ideal. We recently described the application of a bioinformatic prediction method based on quantitative structure-affinity relationship methods to peptide-MHC binding. In this study we demonstrate the predictivity and utility of this approach. We determined the binding affinities of a set of 90 nonamer peptides for the MHC class I allele HLA-A*0201 using an in-house, FACS-based, MHC stabilization assay, and from these data we derived an additive quantitative structure-affinity relationship model for peptide interaction with the HLA-A*0201 molecule. Using this model we then designed a series of high affinity HLA-A2-binding peptides. Experimental analysis revealed that all these peptides showed high binding affinities to the HLA-A*0201 molecule, significantly higher than the highest previously recorded. In addition, by the use of systematic substitution at principal anchor positions 2 and 9, we showed that high binding peptides are tolerant to a wide range of nonpreferred amino acids. Our results support a model in which the affinity of peptide binding to MHC is determined by the interactions of amino acids at multiple positions with the MHC molecule and may be enhanced by enthalpic cooperativity between these component interactions.

Greater CD8+ TCR heterogeneity and functional flexibility in HIV-2 compared to HIV-1 infection

Virus-specific CD8(+) T cells are known to play an important role in the control of HIV infection. In this study we investigated whether there may be qualitative differences in the CD8(+) T cell response in HIV-1- and HIV-2-infected individuals that contribute to the relatively efficient control of the latter infection. A molecular comparison of global TCR heterogeneity showed a more oligoclonal pattern of CD8 cells in HIV-1- than HIV-2-infected patients. This was reflected in restricted and conserved TCR usage by CD8(+) T cells recognizing individual HLA-A2- and HLA-B57-restricted viral epitopes in HIV-1, with limited plasticity in their response to amino acid substitutions within these epitopes. The more diverse TCR usage observed for HIV-2-specific CD8(+) T cells was associated with an enhanced potential for CD8 expansion and IFN-gamma production on cross-recognition of variant epitopes. Our data suggest a mechanism that could account for any possible cross-protection that may be mediated by HIV-2-specific CD8(+) T cells against HIV-1 infection. Furthermore, they have implications for HIV vaccine development, demonstrating an association between a polyclonal, virus-specific CD8(+) T cell response and an enhanced capacity to tolerate substitutions within T cell epitopes.

A novel testosterone gel formulation normalizes androgen levels in hypogonadal men, with improvements in body composition and sexual function

OBJECTIVE

To compare the safety and efficacy of two doses of a new testosterone gel formulation (Testim Auxilium Pharmaceuticals, Inc., Norristown, PA, USA) to a permeation-enhanced testosterone patch (Andropatch), GlaxoSmithKline, UK) for treating men with confirmed low serum testosterone levels, and associated signs and symptoms of hypogonadism.

PATIENTS AND METHODS

In all, 208 men were randomized and treated at 29 centres in Denmark, Germany, Netherlands, Sweden and the UK. The men were treated for 90 days, and the pharmacokinetics and treatment effectiveness of Testim at two doses (50 and 100 mg/day, delivering a daily dose of 5 and 10 mg testosterone, respectively) and Andropatch (2 x 2.5 mg patches, each delivering 2.5 mg testosterone and containing 12.2 mg of testosterone) were compared. Pharmacokinetic profiles were obtained, body composition measured, and mood and sexual function data recorded.

RESULTS

Testim produced dose-dependent improvements in all pharmacokinetic variables compared with Andropatch. The mean increases from baseline to 90 days in testosterone were 12.41, 6.54 and 3.82 nmol/L for Testim 100 and 50 mg/day and the Andropatch, respectively. Both doses of Testim significantly improved positive and negative mood over baseline; Andropatch did not. All three treatments increased lean body mass, and the higher dose of Testim produced a significant decrease in percentage body fat. At all sample times both doses of Testim significantly improved sexual performance, sexual motivation, sexual desire and spontaneous erections. Andropatch provided insignificant improvements from baseline at all sample times for sexual desire, an inconsistent improvement in sexual motivation, but no effect on spontaneous erections. These results are similar to those previously reported for testosterone replacement therapy in hypogonadal men, suggesting that normalization of serum testosterone restores sexual function. However, the present data suggest that higher serum testosterone levels may further improve sexual function. Gel treatment was well tolerated, while patch treatment produced higher rates of application-site reactions and study discontinuation.

CONCLUSION

The favourable pharmacokinetic profile and treatment outcome, combined with the enhanced tolerability of Testim, suggest that this new gel formulation is a safe and effective treatment in men with low serum testosterone levels and associated signs and symptoms of hypogonadism.

The value of risks scores for predicting postoperative nausea and vomiting when used to compare patient group in a randomised controlled trial

Whilst conducting a randomised controlled trial into the effects of combination anti-emetics, we endeavoured to confirm that our patient groups were matched using the predictive scoring systems for postoperative nausea and vomiting (PONV) and postoperative vomiting (POV) reported in the literature. One hundred and seventy-seven female patients attending for day case gynaecological surgery were studied and their individual risks of PONV and POV were calculated using four predictive models for PONV and two predictive models for POV. The scoring systems were then evaluated to see if agreement existed between them using the method described by Bland and Altman. Bias and 95% limits of agreement were calculated for each combination. Agreement between scoring systems was poor. As the scoring systems gave widely divergent predictions, we concluded that the predictive risk for PONV or POV would be dependent upon the scoring system chosen, thus limiting their usefulness in this role.

The use of anaesthetic rooms for induction of anaesthesia: a postal survey of current practice and attitudes in Great Britain and Northern Ireland

A postal survey was sent to all anaesthetic departments in the UK to identify current practice and gain insight into anaesthetists' attitudes regarding the use of anaesthetic rooms for induction of general anaesthesia. Replies were received from 247 (88%) departments. Of these, 10 (4%) departments routinely anaesthetise all patients in theatre. The main reason for change was patient safety. Of those who routinely use the anaesthetic room for induction of anaesthesia, only 5% have made provision to change to in-theatre induction. An estimated pound 30 million has been spent on equipping anaesthetic rooms since 1994; with the result that 91% of departments where anaesthetic room induction occurs, now have monitoring that complies with the current Association of Anaesthetists of Great Britain and Ireland guidelines. The majority of the respondents who use anaesthetic rooms perceived induction in theatre to result in reduced efficiency, increased patient anxiety, a worse teaching environment and no improvement in patient safety. This was in contrast to the attitudes of respondents from hospitals where in-theatre induction occurs. Only 9.7% of all respondents believed that clinical governance would necessitate a change to anaesthetizing all patients in theatre compared to 25% who believed that the increasing costs of monitoring equipment would lead to a change. Overall 79% of respondents prefer to use the anaesthetic room, 16% prefer in-theatre induction and 5% expressed no preference. However, of those who routinely anaesthetise in theatre, 70% thought it to be preferable.

A comparison between midazolam co-induction and propofol predosing for the induction of anaesthesia in the elderly

In a prospective, double-blind, randomised, placebo-controlled trial, we have compared the effects of midazolam co-induction with propofol predosing on the induction dose requirements of propofol in elderly patients. We enrolled 60 patients aged > 70 years, attending for urological surgery. The patients were allocated randomly to one of three groups, to receive either midazolam 0.02 mg.kg(-1), propofol 0.25 mg.kg(-1), or normal saline 2 ml (placebo) 2 min prior to induction of anaesthesia using propofol 1% infusion at 300 ml.h(-1). The propofol dose requirements for induction were recorded for two end-points (loss of verbal contact and insertion of an oropharyngeal airway). Cardiovascular parameters were recorded at 1-min intervals for each patient until induction was complete. The midazolam group showed a significant reduction in propofol dose requirements for induction (p = 0.05) compared to the placebo group. The propofol group did not show a significant dose reduction compared to placebo. There were no demonstrable differences in terms of improved cardiovascular stability between groups. We conclude that propofol predosing does not significantly reduce the induction dose of propofol required in the elderly, and there were no cardiovascular benefits to either midazolam co-induction or propofol predosing in the elderly.

Management of life-threatening autonomic hyper-reflexia using magnesium sulphate in a patient with a high spinal cord injury in the intensive care unit

We report the successful use of i.v. magnesium sulphate to control life-threatening autonomic hyper-reflexia associated with chronic spinal cord injury in the intensive care environment. A 37-yr-old, male was admitted to the intensive care unit with a diagnosis of septic shock and acute renal failure secondary to pyelonephritis. He had been found unresponsive at home following a 2-day history of pyrexia and purulent discharge from his suprapubic catheter. He had sustained a T5 spinal cord transection 20 yr previously. Initial management included assisted ventilation, fluid resuscitation, vasopressor support, and continuous veno-venous haemofiltration. The sepsis was treated with antibiotic therapy and percutaneous nephrostomy drainage of the pyonephrosis. On the fifth day, the patient developed profuse diarrhoea. This was associated with paroxysms of systemic hypertension and diaphoresis, his arterial pressure rising on occasion to 240/140 mm Hg. A diagnosis of autonomic hyper-reflexia was made and a bolus dose of magnesium sulphate 5 g was administered over 15 min followed by an infusion of 1-2 g h(-1). There was an almost immediate decrease in the severity and frequency of the hypertensive episodes. There were no adverse cardiac effects associated with the administration of magnesium, only a slight decrease in minute ventilation as the plasma level approached the upper end of the therapeutic range (2-4 mmol litre(-1)). In view of the beneficial effects observed in this case we advocate further research into the use of magnesium sulphate in the treatment or prevention of autonomic hyper-reflexia secondary to chronic spinal cord injury in the intensive care unit.

Maternal depression and increased fetal activity

Pregnant women with (n = 45) and without (n = 45) symptoms of depression (CES-D score of 16 or more) were provided ultrasound examinations during the second and third trimesters. An analysis of variance on the cross-sectional data yielded a significant diagnosis by gestational month interaction effect (P < 0.05). The fetuses of depressed mothers spent significantly more time being active during the fifth, sixth and seventh gestational months than fetuses of non-depressed mothers. A stepwise regression analysis revealed that 35% of the variance in time being active could be accounted for by the combined depression and trait anxiety scores of the mothers. These findings suggest that maternal depression correlated with increased fetal activity. These data also highlight the need for research on the potential effects of stress hormones on fetal activity.

Identification and quantification of phosphodiesterase 4 subtypes in CD4 and CD8 lymphocytes from healthy and asthmatic subjects

In the present study, for the first time, PDE4 subtypes were identified and semi-quantified in both CD4 and CD8 lymphocytes from healthy and asthmatic individuals. CD4 and CD8 lymphocytes from healthy and mild asymptomatic asthmatic subjects (receiving beta-agonist therapy only) were isolated from peripheral venous blood using appropriate antibody coated paramagnetic beads. PDE4 subtypes and beta-actin were identified by digoxigenin (DIG)-labelling reverse transcriptase-polymerase chain reaction and semi-quantified by DIG-detection enzyme-linked immunosorbance assay. In CD4 and CD8 lymphocytes PDE4A, PDE4B and PDE4D were detected, with no significant differences observed between healthy and asthmatic groups. In CD8 lymphocytes, enzyme subtype expression was lower and showed more intersubject variability. In functional studies investigating the effects of various PDE inhibitors on PHA-induced proliferation of mononuclear cells from healthy and asthmatic subjects, CDP840 (0.03 - 10 microM), rolipram (0.1 - 10 microM) and theophylline (10 microM - 1 mM) inhibited PHA-induced proliferation of mononuclear cells from healthy and asthmatic subjects in a concentration-dependent manner, although no significant difference was observed between the groups investigated. In additional studies, total monocyte cyclic AMP PDE activity was investigated in cells isolated from asthmatic subjects both prior to and 24 h after allergen challenge. Total monocyte cyclic AMP PDE activity remained unaffected following challenge of asthmatic subjects with either house dust mite or cat dander and was inhibited in a concentration-dependent manner by rolipram (0.01 - 100 microM) both before and after allergen challenge.

Polymer chemical structure is a key determinant of physicochemical and colloidal properties of polymer-DNA complexes for gene delivery

Polyplexes are now emerging as potentially useful vectors for gene therapy. To improve our understanding of how the chemical structure of the polymer affects the properties of these systems, a series of structurally related polymers, the linear poly(amidoamine)s (PAAs), have been examined for their abilities to form complexes with DNA. Structure-dependent differences in DNA binding are shown by gel electrophoretic retardation of DNA and thermal transition analyses. Two PAAs, NG28 and NG30, stand out as having high affinity DNA binding characteristics, similar to the model homopolypeptide, poly-L-lysine. In addition, differences in complex formation, particle size and surface charge are displayed for the different polymer-DNA systems. Electron microscopy studies showed that the polymers condensed DNA into similar unit structures but only complexes with NG30 did not undergo agglomeration. This was attributed to an excess of complexed polymer forming a shell of uncomplexed polymer chain segments around a condensed DNA-polymer core. The transfection activities of these polymer complexes differ greatly, and some of these differences can be explained in a multifactorial way by the physicochemical and colloidal properties. It is concluded that polymer chemical structure dictates the apparent affinity of DNA binding, and also several of the important colloidal characteristics of the resulting complexes.

Right frontal EEG asymmetry and lack of empathy in preschool children of depressed mothers

EEG activity, empathic reactions to emotion-inducing stimuli, and the ability to complete a teaching task were examined in preschool children of depressed and non-depressed mothers. EEG activity from frontal and parietal regions was recorded. Repeated measures MANOVAs indicated that the children of depressed mothers had greater relative right frontal EEG asymmetry, a pattern that typically accompanies greater negative affect and showed less empathic responses to a crying infant as well as to their own mothers' simulated distress. Children of depressed mothers were slower in completing the teaching task (involving mutual cooperation with their mother) and they spent more time asking for help than children of non-depressed mothers. Further, the depressed mothers stated their approval less often and spent less time helping their child complete the task.

Massage and music therapies attenuate frontal EEG asymmetry in depressed adolescents

EEG asymmetry, specifically greater relative right frontal activation, is associated with negative affect. Depressed adults show stable patterns of this asymmetry. The present study assessed the effects of massage therapy and music therapy on frontal EEG asymmetry in depressed adolescents. Thirty adolescents with greater relative right frontal EEG activation and symptoms of depression were given either massage therapy (n = 14) or music therapy (n = 16). EEG was recorded for three-minute periods before, during, and after therapy. Frontal EEG asymmetry was significantly attenuated during and after the massage and music sessions.

One-year-old infants of intrusive and withdrawn depressed mothers

This study examined behaviors of intrusive/depressed versus withdrawn/depressed mothers and their one-year-old infants during a structured teaching interaction. Group comparisons revealed that intrusive/depressed mothers showed more positive responses, more demonstrating toys, and more physical guidance, and their infants demonstrated less toy manipulation. Withdrawn/depressed mothers maintained infant play more frequently and showed more restricted affect, and their infants demonstrated less affective behavior, both positive and negative. These findings suggested that exposure to depressed mothers' nonoptimal interaction styles represents different types of risk to infants' cognitive and affective development.

The regulation of AMP-activated protein kinase by phosphorylation

The AMP-activated protein kinase (AMPK) cascade is activated by an increase in the AMP/ATP ratio within the cell. AMPK is regulated allosterically by AMP and by reversible phosphorylation. Threonine-172 within the catalytic subunit (alpha) of AMPK (Thr(172)) was identified as the major site phosphorylated by the AMP-activated protein kinase kinase (AMPKK) in vitro. We have used site-directed mutagenesis to study the role of phosphorylation of Thr(172) on AMPK activity. Mutation of Thr(172) to an aspartic acid residue (T172D) in either alpha1 or alpha2 resulted in a kinase complex with approx. 50% the activity of the corresponding wild-type complex. The activity of wild-type AMPK decreased by greater than 90% following treatment with protein phosphatases, whereas the activity of the T172D mutant complex fell by only 10-15%. Mutation of Thr(172) to an alanine residue (T172A) almost completely abolished kinase activity. These results indicate that phosphorylation of Thr(172) accounts for most of the activation by AMPKK, but that other sites are involved. In support of this we have shown that AMPKK phosphorylates at least two other sites on the alpha subunit and one site on the beta subunit. Furthermore, we provide evidence that phosphorylation of Thr(172) may be involved in the sensitivity of the AMPK complex to AMP.

Cell damage-induced conformational changes of the pro-apoptotic protein Bak in vivo precede the onset of apoptosis

Investigation of events committing cells to death revealed that a concealed NH2-terminal epitope of the pro-apoptotic protein Bak became exposed in vivo before apoptosis. This occurred after treatment of human Jurkat or CEM-C7A T-lymphoma cells with the mechanistically disparate agents staurosporine, etoposide or dexamethasone. The rapid, up to 10-fold increase in Bak-associated immunofluorescence was measured with epitope-specific monoclonal antibodies using flow cytometry and microscopy. In contrast, using a polyclonal antibody to Bak, immunofluorescence was detected both before and after treatment. There were no differences in Bak protein content nor in subcellular location before or after treatment. Immunofluorescence showed Bcl-xL and Bak were largely associated with mitochondria and in untreated cells they coimmunoprecipitated in the presence of nonioinic detergent. This association was significantly decreased after cell perturbation suggesting that Bcl-xL dissociation from Bak occurred on exposure of Bak's NH2 terminus. Multiple forms of Bak protein were observed by two dimensional electrophoresis but these were unchanged by inducers of apoptosis. This indicated that integration of cellular damage signals did not take place directly on the Bak protein. Release of proteins, including Bcl-xL, from Bak is suggested to be an important event in commitment to death.

Aromatherapy positively affects mood, EEG patterns of alertness and math computations

EEG activity, alertness, and mood were assessed in 40 adults given 3 minutes of aromatherapy using two aromas, lavender (considered a relaxing odor) or rosemary (considered a stimulating odor). Participants were also given simple math computations before and after the therapy. The lavender group showed increased beta power, suggesting increased drowsiness, they had less depressed mood (POMS) and reported feeling more relaxed and performed the math computations faster and more accurately following aromatherapy. The rosemary group, on the other hand, showed decreased frontal alpha and beta power, suggesting increased alertness. They also had lower state anxiety scores, reported feeling more relaxed and alert and they were only faster, not more accurate, at completing the math computations after the aromatherapy session.

The Drosophila Pax gene eye gone is required for embryonic salivary duct development

What are the developmental mechanisms required for conversion of an undifferentiated, two-dimensional field of cells into a patterned, tubular organ? In this report, we describe the contribution of the Drosophila Pax gene eye gone to the development of the embryonic salivary glands and ducts. eye gone expression in salivary tissues is controlled by several known regulators of salivary fate. After the initial establishment of the salivary primordium by Sex combs reduced, fork head excludes eye gone expression from the pregland cells so that its salivary expression is restricted to the posterior preduct cells. trachealess, in contrast, activates eye gone expression in the posterior preduct cells. We have previously described the process by which fork head and the EGF receptor pathway define the border between the gland and duct primordia. Here we show that eye gone is required for the subdivision of the duct primordium itself into the posterior individual duct and the anterior common duct domains. In the absence of eye gone, individual ducts as well as the precursor of the adult salivary glands, the imaginal ring, are absent. We took advantage of this ductless phenotype to show that Drosophila larvae do not have an obligate requirement for salivary glands and ducts. In addition to its role in the salivary duct, eye gone is required in the embryo for the development of the eye-antennal imaginal disc and the chemosensory antennal organ.

Cisplatin- and paclitaxel-induced apoptosis of ovarian carcinoma cells and the relationship between bax and bak up-regulation and the functional status of p53

We investigated the roles of p53 and Bcl-2 homologues in the induction of apoptosis by cisplatin and paclitaxel in wild-type p53-expressing human ovarian carcinoma cells and cisplatin-resistant derivatives that have lost p53 function. Cisplatin induced apoptosis in parental A2780 but not in cisplatin-resistant A2780/cp70 cells, whereas paclitaxel induced apoptosis in both cell lines. Immunoprecipitation of p53 using antibodies specific for p53 conformation (pAb 1620 and pAb 240) showed that there were no relative changes in p53 conformation before and after cisplatin treatment in either cell line. A2780/cp70 cells have lost p53 function, yet they have wild-type p53 gene sequence. However, A2780/cp70 cells constitutively express more p53 in a form detected by pAb 240, an antibody that also detects mutant conformations of p53 that are transcriptionally inactive. There were no changes in levels of Bcl-2, Bcl-XL, or 24-kDa Bax over 72 hr after exposure to cisplatin or paclitaxel, but each agent led to up-regulation of Bak and 21-kDa Bax in A2780 cells. Paclitaxel, but not cisplatin, increased Bak and 21-kDa Bax levels in A2780/cp70 cells. These data suggest that apoptosis in A2780 and A2780/cp70 is associated with an increased level of Bak and 21 kDa Bax after drug-induced damage and that functional p53 may be required for this effect after cisplatin but not after paclitaxel.

EEG stability in infants/children of depressed mothers

The stability of EEG was examined in infants of depressed (BDI > 16) and non-depressed mothers (BDI < 9) from 3 months to 3 years. Of the 32 infants seen at 3 months, 15 were seen again at 3 years of age. Seven of the eight children who had exhibited right frontal EEG asymmetry as infants still showed that EEG asymmetry pattern at the 3 year visit. Children with right frontal EEG asymmetry at 3 years were observed to be more inhibited during an exploratory play task, and children of depressed versus non-depressed mothers were less empathetic during simulated maternal distress.

A randomized controlled trial of double-versus single-gloving in vascular surgery

With the increasing incidence of hepatitis B and HIV, and the increasing awareness of the risk and prevalence of hepatitis C, it is becoming even more necessary to adopt stricter policies to safeguard personnel and to reduce the risk of transmission. Previous studies have shown a need for eye protection, protective clothing and the use of double-gloving during operative or interventional procedures. The risk of infection is much less with unbroken skin and conversely more likely when hollow needles are used. Arguments against the routine use of double-gloving include the loss of dexterity and the discomfort incurred, and the potential loss of dexterity that might theoretically result in more rather than fewer needle-stick injuries.

EEG activation in 1-month-old infants of depressed mothers

Previous research has documented differences in the pattern of EEG activation between 3-month-old infants of depressed mothers and infants of nondepressed mothers. In the present study, EEG was recorded in even younger 1-month-old infants of depressed and nondepressed mothers. The infants of depressed mothers exhibited greater relative right frontal EEG asymmetry (due to reduced left frontal activation), and this pattern at 1 month was significantly related to 3-month EEG asymmetry. Right frontal EEG asymmetry was also related to more frequent negative facial expressions (sad and pre-cry faces) during the Brazelton exam. Finally, the infants of depressed mothers showed more indeterminate sleep, were less active, and cried less than infants of nondepressed mothers.

Cisplatin, camptothecin, and taxol sensitivities of cells with p53-associated multidrug resistance

With the use of clonogenic survival assays, we show that wild-type p53-expressing A2780 human ovarian cell lines transfected with a dominant negative mutant p53 gene (codon 143, valine to alanine) acquired cross-resistance to ionizing radiation, cisplatin, doxorubicin, and 1-beta-D-arabinofuranosylcytosine. However, these mutant p53-transfected cell lines retained sensitivity to taxol and camptothecin. We also show that immature thymocytes from mice with the p53 gene genetically inactivated showed reduced ability to undergo apoptosis after treatment with ionizing radiation and cisplatin compared with wild-type mice. However, taxol-induced apoptosis in thymocytes does not seem to be dependent on p53 status. Camptothecin also induced apoptosis in a p53-independent manner in thymocytes at low doses but in a p53-dependent manner at high doses. These data suggest that taxoids and camptothecin analogs could have activity in tumors that have aberrant p53 function and provide a rationale for the clinical observations of responsiveness of refractory ovarian cancer to these drugs.

DNA-damaging agents induce both p53-dependent and p53-independent apoptosis in immature thymocytes

Apoptosis in the immature thymus can be induced by both p53-dependent and -independent pathways, the former being activated by exposure to DNA-damaging agents and the latter being induced by glucocorticoids [Nature (Lond.) 362:847-849; Nature (Lond.) 362:849-852 (1993)]. We report that the DNA-damaging agents etoposide and gamma-radiation induced similar levels of apoptosis in both proliferatively enriched and quiescent immature rat thymocytes, as assessed by flow cytometry and the formation of both kilobase-pair and 180-bp integer fragments of DNA. However, a marked stabilization of p53 occurred exclusively in the proliferatively enriched population, which was also enriched for immature CD4- CD8- and mature CD4+ CD8-/CD4- CD8+ cells. In contrast, DNA damage-induced apoptosis in quiescent mature peripheral T cells was associated with an accumulation of p53. Our studies suggest that stabilization of p53 in thymocytes in response to DNA damage may be developmentally regulated. In immature thymocytes obtained from p53-null mice, DNA-damaging agents induced apoptosis at significantly lower levels and at later times than that seen in cells from p53 wild-type animals. These data support the hypothesis that DNA-damaging agents induce apoptosis primarily via a p53-dependent pathway in immature thymocytes as previously reported. We report here that DNA damage can also induce apoptosis by a p53-independent pathway in a particular subpopulation of immature thymocytes.

Comparison of lower limb arterial assessments using color-duplex ultrasound and ankle/brachial pressure index measurements

The strength of agreement between two noninvasive methods of assessing lower limb arterial disease and their relationship to patient symptoms following exercise have been investigated. Color-duplex ultrasound (CDU) and ankle/brachial pressure index (ABPI) (before and afer exercise) measurements were obtained from 200 consecutive patients referred to a vascular investigations laboratory. From these patients, 290 limbs were available for study, comprising limbs without previous vascular surgery, from patients without diabetes and who could attempt a walking exercise test. The overall level of agreement between CDU and resting ABPI measurements was 83% (Kappa 0.66). The ABPI technique identified the more serious disease; a resting ABPI of less than 0.6 gave 100% agreement with CDU. With higher resting ABPIs the level of agreement became poorer: 83% (0.6 < or = ABPI <0.9) and 76% (normal ABPI > or = 0.9). The addition of postexercise ABPI measurements in determining significant arterial disease increased the strength of relationship between the two techniques by only 2% (85%, Kappa 0.69). The exercise test was generally limited by the most symptomatic limb in each patient, and the agreement between CDU and postexercise ABPI measurements in these limbs was higher at 93% (Kappa 0.81). In comparison, agreement for the least symptomatic group of limbs was found to be poor (69%, Kappa 0.37). Compared with symptoms after exercise, overall agreements with CDU and ABPI were both 67% (Kappa 0.27). The agreement was better (91%) when the resting ABPI was less than 0.6. The ABPI is biased toward the detection of more severe disease and is more consistent with CDU when the most symptomatic limbs are compared. The relationship between either test and symptoms after exercise is strong only for limbs with major disease.

Prosthetic graft infection in the descending thoracic aorta treated by extra-anatomic rerouting

Prosthetic aortic graft infection is a dreaded complication associated with high mortality. Some of the best results have been achieved with removal of the infected prosthesis, although this is not always possible in the case of the thoracic aorta. A patient with an infected coarctation graft managed by aortic rerouting is described here.

Down-regulation but not phosphorylation of stathmin is associated with induction of HL60 cell growth arrest and differentiation by physiological agents

Stathmin is a cytosolic phosphoprotein that has an important but, as yet, undefined role in cell proliferation and differentiation. Induction of growth arrest and differentiation of HL60 cells to monocytes by phorbol 12-myristate 13-acetate is associated with rapid phosphorylation of the protein. Stathmin phosphorylation was not seen when HL60 cells were induced to differentiate to monocytes, by 1 alpha, 25-dihydroxyvitamin D3, and to neutrophils, by all-trans retinoic acid and granulocyte colony stimulating factor. In all the above instances, stathmin expression was down-regulated. Thus, increased stathmin phosphorylation is not required for cell growth arrest or differentiation or down-regulation of stathmin expression.

Stathmin expression is a feature of proliferating cells of most, if not all, cell lineages

BACKGROUND

Stathmin is a phylogenetically conserved protein which was identified initially as a prominent cytosolic protein in hemopoietic cells, endocrine cells, brain, and testis. In these tissues, it has been suggested that the level of stathmin expression is important in development and cell proliferation. Furthermore, stathmin phosphorylation appears to be involved in the regulation of cell growth arrest, terminal differentiation, and hormone secretion. Elevated levels of expression of stathmin have been described in leukemia and lymphoma cells. The aim of this study was to characterize the distribution of cells that express the stathmin protein in a wide variety of normal human and rodent tissues.

EXPERIMENTAL DESIGN

First, antisera against a synthetic stathmin peptide have been raised in rabbits and the specificity of these antisera confirmed by their reactivity with stathmin on 1-dimensional and 2-dimensional Western blots. Second, the most appropriate means of fixing tissues in order to stain stathmin has been investigated. Finally, using the optimized conditions of tissue fixation, the antisera have been used to immunostain sections taken from a wide variety of tissues.

RESULTS

Immunopositivity was found in cells of all the lineages studied, with the stained cells present within the proliferating compartment of tissues. Conversely, most nonproliferating mature cells did not stain with the antisera to stathmin. The only nonproliferating cells that appeared to express stathmin were a subpopulation of glial cells, neurons, and anterior pituitary cells.

CONCLUSIONS

It is proposed that stathmin is necessary for cell proliferation in most, or all, cell lineages and that its primary function relates to some aspect of cell division.

Persistent growth of BALB/C mouse plasmacytoma and human myeloma cell lines in the presence of phorbol myristate acetate is associated with continued expression of Lap18 (stathmin)

Lap18 is a highly conserved cytosolic protein that is expressed in dividing cells. Data from a number of studies show that a range of cell lines and mitogen-stimulated normal cells cultured in PMA phosphorylate and subsequently down-regulate Lap18. This has been found to be associated with growth arrest, although it is not clear that these events are causally related. In the present study we confirm that the HL60 promyelocytic leukemia and K562 erythroleukemia cell lines, when cultured with PMA, behave in this manner. This was not the case for any of five mouse plasmacytoma cell lines and six lines derived from patients with multiple myeloma or plasma cell leukemia. All of these lines contain Lap18, although the level of this protein in the mouse but not the human plasmacytoma cell-line cells is relatively low. All the neoplastic plasma cell-line cells phosphorylate Lap18 on culture with PMA, but this does not induce growth arrest nor result in down-regulation of Lap18 expression. Further experiments are required to test whether there is a mechanistic relationship between the continued growth of plasmacytoma cell lines and their failure to down-regulate Lap18 on culture in PMA.

EFFECT OF THE MENSTRUAL CYCLE PHASE AND DIET ON BLOOD LACTATE RESPONSES TO EXERCISE

Previous research has shown women on normal mixed diets have varied blood lactate (LA) responses to exercise across their menstrual cycle (MC) phases. This study examined the effect of diet on this finding. Eurmenonrheic women (n=10) completed a discontinuous exercise protocol consisting of 4 intervals of 6 min exercise, separated by 6 min rest, at 30, 50, 70 and 90% V̇O₂max. The exercise was performed after a 3 day pen od under each of the following conditions: 1 - low carbohydrate (35% of total caloric intake) - mid-follicular phase (LCHO-FP), 2 - low carbohydrate - mid-luteal phase (LCHO-LP), 3 - high carbohydrate (75%) - mid-follicular phase (HCHO-FP), 4 - high carbohydrate - mid-luteal phase (HCHO-LP). Eucaloric status was maintained during the study. The MC phase was confirmed by blood hormonal levels. Significant (P<0.05) MC phase - diet interaction effects were found. LA was lower at 70% V̇O₂max in the LCHO-LP (3.7±0.2 mmol·l^-1) than at the other conditions (5.0±0.7 to 6.0±0.7 mmol·l^-1; mean ±SEM). Also, LA during LCHO-LP at rest and all other exercise intensities tended to be lower than all other MC phase/diet conditions (P<0.06). LA responses at rest and during exercise in the HCHO-LP, HCHO-FP, and LCHO-FP conditions did not differ significantly. The present findings demonstrate that an "athletic type diet", high in carbohydrates, negates the menstrual cycle phase difference in lactate responses to exercise previously reported in the literature; however, the menstrual phase differences do exist when a diet low in carbohydrates is consumed.

Eye protection for the vascular surgeon

Contamination occurring during vascular surgery was studied prospectively using a surgical mask incorporating a Splashguard visor. Over a 16-week period 78 vascular procedures were included; 44 were of < 2 h duration and 34 were of > or = 2 h. Contamination on both mask and visor from blood spots was recorded at the end of each procedure. Overall, 51 per cent of principal surgeons' visors were contaminated, with contamination of the mask itself in 32 per cent. When two surgeons were operating the contamination rate for the second was also high: 36 per cent for the visor and 42 per cent for the mask. Assistants had a contamination rate of 36 per cent for the visor and 13 per cent for the mask. The lowest rate of contamination occurred for the visor and mask of the scrub nurse, 10 and 4 per cent respectively. For emergency procedures the duration of operation had no influence on the frequency of contamination. However, for the principal surgeon elective operations of < 2 h duration were less likely to involve contamination than those of > or = 2 h (P < 0.035). Blood contamination of visors and masks is common in vascular surgery but rarely appreciated by the surgeon. Routine eye protection should be considered in vascular surgery, in particular for emergency and prolonged elective procedures.

Electroencephalogram asymmetry during emotionally evocative films and its relation to positive and negative affectivity

The purpose of the present study was to determine if there were differences in hemispheric lateralization during the experience of emotions and if those differences were related to personality style. College-age adult subjects selected for high positive and negative affectivity on Tellegen's Multidimensional Personality Questionnaire (MPQ; Tellegen, 1982) viewed video stimuli selected for their emotionally evocative nature and rated the intensity of the emotions they experienced. The ongoing electroencephalogram (EEG) was recorded while they watched the video clips. Analyses of the EEG data revealed that there were differences in regional activation during the emotional video clips, especially for those stimuli selected to elicit either happy or disgust emotions. These results support the hypothesis that the right hemisphere is specialized for the experience of certain negative affects, whereas the left hemisphere is specialized for the experience of certain positive affects. The findings also indicated some support for the theory that individual differences in personality style are related to differing levels of hemispheric arousal.

Changes in the phosphorylation status of a 19 kD cytosolic protein are linked to the growth arrest of HL-60 cells

A major 19 kD cytosolic protein (p19) has been described in a number of cell systems with respect to its rapid phosphorylation when protein kinase C is activated and has been proposed as a key substrate of this enzyme. Phosphorylation of p19 occurs when the growth of cells is affected by 12-O-tetradecanoylphorbol-13-acetate (TPA) and it has been proposed that increased phosphorylation of p19 relates to the cessation of cell growth. This study delineates precisely the relationship between p19 phosphorylation changes in the growth and differentiation status of cells. Changes in the levels of two phosphorylated forms of p19 were assessed in HL-60 promyelocytic cells and a variant HL-60 cell line which stopped growing and differentiated in response to TPA and were compared to changes seen in HL-60 variant lines which merely growth arrested when treated with TPA. In lines which either did or did not differentiate, in response to TPA, the p19 protein was rapidly and transiently phosphorylated. Thus, this alteration in the phosphorylation status of p19 is associated with the process of growth arrest and not related to the onset of cell differentiation. The p19 protein and the enzymes which effect its phosphorylation status modulate the growth of cells and possible disregulation of p19 and/or its kinases and phosphatases is of interest as regards the leukaemic transformation of cells.

The specificity of technetium-labelled-leucocyte imaging of aortic grafts in the early postoperative period

Radio-labelled-leucocyte imaging is becoming accepted as the investigation of choice when infection of prosthetic arterial bypass grafts is suspected. However, alternative sources of inflammation, such as haematoma and, perhaps, the healing and incorporation of newly inserted bypass grafts, are potential causes of false positive results. This study examines the use of technetium-labelled-leucocyte imaging during the postoperative in-hospital period following aortic bypass surgery. Two labelled-leucocyte scans were carried out serially in 20 patients randomly allocated to receive either of two types of Dacron aortic graft in regular use. The earlier scans were undertaken at 2-5 days after surgery and only two of these scans were positive. None of the later scans, undertaken at 7-10 days after surgery, was positive. None of the patients had a graft injection as evidenced by clinical features, leucocyte counts, and C-reactive protein measurements. These results suggest that recent surgery does not in itself significantly reduce the specificity of technetium-labelled-leucocyte imaging.