Spirocyclic nonpeptide glycoprotein IIb-IIIa antagonists. Part 2: design of potent antagonists containing the 3-azaspiro[5.5]undecanes

The synthesis and biological activity of novel glycoprotein IIb-IlIa anatagonists containing 3-azaspiro[5.5]undec-9-yl nucleus are described. The potent activity of these compounds as platelet aggregation inhibitors demonstrates the utility of the monoazaspirocyclic structure as central template for nonpeptide RGD mimics.

Sports doctors' resuscitation skills under examination: do they take it seriously?

As 64% of sports medicine doctors were unable to show proficiency at basic life support and assessment and management of a seriously injured patient with a potential spinal injury in the last two examinations for a University of Bath diploma in sports and exercise medicine, it was decided that a reminder is required of the importance of acquiring, at the very least, some basic resuscitation skills. An analysis and comment on the results from the first aid component of the examination is also presented.

The extra domain A of fibronectin activates Toll-like receptor 4

Cellular fibronectin, which contains an alternatively spliced exon encoding type III repeat extra domain A (EDA), is produced in response to tissue injury. Fragments of fibronectin have been implicated in physiological and pathological processes, especially tissue remodeling associated with inflammation. Because EDA-containing fibronectin fragments produce cellular responses similar to those provoked by bacterial lipopolysaccharide (LPS), we examined the ability of recombinant EDA to activate Toll-like receptor 4 (TLR4), the signaling receptor stimulated by LPS. We found that recombinant EDA, but not other recombinant fibronectin domains, activates human TLR4 expressed in a cell type (HEK 293 cells) that normally lacks this Toll-like receptor. EDA stimulation of TLR4 was dependent upon co-expression of MD-2, a TLR4 accessory protein. Unlike LPS, the activity of EDA was heat-sensitive and persisted in the presence of the LPS-binding antibiotic polymyxin B and a potent LPS antagonist, E5564, which completely suppressed LPS activation of TLR4. These observations provided a mechanism by which EDA-containing fibronectin fragments promote expression of genes involved in the inflammatory response.

Zirconium speciation in lactate solutions and polyacrylate gels

Controlling gelation kinetics is an important objective for several applications (ceramic and thin film syntheses, reduction in permeability of porous rock, etc). There is a growing interest in studying the gelation of polymers by zirconium, a crosslinker of lower toxicity than the chromium which is still commonly used. XAS at the Zr K-edge was performed at the European Synchrotron Radiation Facility (ESRF) on the BM32 beamline. The fluorescence detection was used to carry out successful in situ speciation at concentrations as low as 36 ppm. The Zr speciation was determined both in ZrLa (where La stands for lactate) aqueous solutions and in gels of a terpolymer of acrylamide having 2% of zirconium reactive acrylate side groups and 2% of sulfonate groups introduced to prevent syneresis. XANES results show that Zr is always in a dodecahedral geometry. In ZrLa solutions. EXAFS results indicate that Zr species grow from a dimer Zr2(La)6 to a tetramer (Zr4(La)x) and then to larger polymers resulting from tetramer associations, as the Zr concentration decreases from 51840 ppm to 36ppm. In polymer gels, Zr species appear to be dimers at pH 6 while tetramers are found when gelation occurred at pH 7. Calculations taking into account multiple scattering effects as well as dynamic molecular calculation confirmed conclusions derived from conventional EXAFS analysis.

Health management in the new millennium. Technology brings value

Informatics tools and agreements, evidence-based guidelines and principles, narrowed practice variation and better knowledge of appropriate and cost-effective techniques for managing health could allow us to control much of the rising cost of health care arising each year from increases in the volume and intensity of medical services, determined by clinical decisions.

Bereavement education for childcare professionals

Bereavement is a stressor that affects not only the child but also the whole family. Children need time and support to come to terms with their grief. Current evidence suggests that professionals feel ill equipped to deal with these issues. Inter-professional, multi-agency collaboration and support can provide effective, integrated and supportive services. A 12-day modular course was developed within the Exeter Community Trust and accredited by the University of Plymouth.

Ultrasonic assessment of physiological echo-contrast agent distribution in brain parenchyma with transient response second harmonic imaging

OBJECTIVES

The present study was designed to provide normal data of transient response second harmonic imaging (TRSHI) examinations of cerebral echo contrast enhancement using different modes of electrocardiogram (ECG) gating and echo-contrast agent doses.

MATERIALS AND METHODS

Fifty-five patients were examined in an axial diencephalic plane of section using the transtemporal acoustic bone window. TRSHI examinations (ECG gating: systolic, frame-rate once every 2 cardiac cycles = "basical instrument setting") could be performed in 50 individuals with adequate insonation conditions after application of 4 g of a galactose-based microbubbles suspension in a concentration of 400 mg/ml. For comparison, diastolic ECG gating (20 patients), cardiac-cycle triggering frequency of once every 2 seconds (15 patients), or an echo contrast agent dose of 2 g Levovist (15 patients) were used. Analysis of peak intensities (PIs) and areas under the curve (AUCs) was done in posterior (region of interest [ROI]a) and anterior (ROIb) parts of the thalamus, in the lentiform nucleus (ROIc), and the white matter (ROId).

RESULTS

In 41 patients with basical instrument setting, characteristic time intensity curve (TIC) could be detected in all ROIs. In ROIa (90%) and ROIb (82%), focal contrast enhancement was most difficult to visualize, and in ROIc and ROId, characteristic TICs were observable in more than 90% of the examinations. Background subtracted PIs and AUCs were significantly higher in ROIc (mean PI: 12.2 +/- 8 acoustic units [AUs]; mean AUC: 598.8 +/- 451.1 AU x Cardiac cycles), and ROId (11.8 +/- 6.9; 559.2 +/- 404) as compared to ROIa (8.3 +/- 5.2; 368.9 +/- 242.7) and ROIb (7.1 +/- 4.7; 298.2 +/- 199.1) (P < .0001). Values for corresponding examinations with a diastolic ECG gating and a cardiac cycle triggering frequency of once every 2 seconds were not different as compared to the basical instrument setting. A 4 g Levovist dose increased the portion of typical TIC in all ROIs. PI of 4 g examinations were significantly higher in ROId and ROIb as compared to the 2 g examination.

CONCLUSION

Our findings indicate that TRSHI allows noninvasive assessment of focal cerebral contrast enhancement in the majority of patients with adequate insonation conditions. This study provides data about normal quantitative and qualitative TRSHI values in patients without cerebrovascular diseases. A dose of 4 g Levovist is recommended in those individuals with inaccurate echo contrast enhancement using the 2 g dose.

No confirmation for a causal role of volume-regulated chloride channels in ischemic preconditioning in rabbits

Volume-regulated chloride channels have recently been proposed to be end-effectors in ischemic preconditioning. The present study attempted to confirm this hypothesis by looking both at cardioprotection and channel activity. In isolated rabbit cardiomyocytes, hypo-osmotic stress (167 mosm/l) induced a current with a magnitude of 2-5 pA/pF at 60 mV. That current could be blocked by the selective chloride channel blockers 5-nitro-2-(3-phenylpropylamino) benzoic acid (NPPB) or indanyloxyacetic acid 94 (IAA-94), but only at 100 microM and 1 m M respectively. Lower concentrations were not effective. Because the channel-blocking concentrations were toxic in isolated perfused rabbit hearts, as evidenced by cessation of cardiac contraction and massive infarction, neither agent could be tested against preconditioning's anti-infarct effect. NPPB and IAA-94 at 1 microM and 10 microM, respectively (the doses used in a previous report), did not affect coronary flow, heart rate and developed pressure, and also did not prevent the infarct size reduction of ischemic preconditioning with 5 min global ischemia/10 min reperfusion preceding 30 min of regional ischemia and 120 min of reperfusion [11. 4(+/-3.6) and (11.1(+/-3.7)% infarction of risk area, respectively]. The volume-regulated chloride and organic osmolyte channel blocker 4, 4;-diisothiocyanostilbene-2,2;-disulfonic acid (DIDS) at 100 microM blocked the hypo-osmotically induced current in myocytes, but again could not be used, since it induced total cessation of cardiac contraction and reduced infarct size in non-preconditioned hearts. Our data do not confirm a prior study on a causal role for volume-regulated chloride channels in the protection of ischemic preconditioning. This hypothesis remains to be adequately tested.

Do out-of-hours co-operatives improve general practitioners' health?

General practitioners (GPs) have been found to have a higher level of anxiety and depression then hospital managers and consultants. In 1995 and 1998, we surveyed GPs in Buckinghamshire. We found that the development of out-of-hours co-operatives was an important factor in the improvement in GPs' health status.

Less afterload sensitivity in short-term hibernating than in acutely ischemic and stunned myocardium

Short-term hibernating myocardium is characterized by reduced contractile function during persistent moderate ischemia, the recovery of metabolic parameters, and the absence of necrosis. To study the afterload dependence of regional wall excursion in short-term hibernating myocardium, in 11 enflurane-anesthetized swine the left anterior descending coronary artery was cannulated and hypoperfused for 90 min to reduce anterior systolic wall thickening (WT, sonomicrometry) by 60%. Under control conditions, at 5 and 90 min ischemia the descending thoracic aorta was acutely constricted to increase left ventricular (LV) pressure by 30 mmHg. Under control conditions, increased LV pressure resulted in decreased WT [i.e., a negative slope of the relationship between WT and LV end-systolic pressure: -11.2 +/- 4.2 (SD) microm/mmHg]. This slope was further significantly decreased at 5 min ischemia (-26.5 +/- 8.8 microm/mmHg) but returned toward control values in short-term hibernating myocardium at 90 min ischemia (-17.2 +/- 6.6 microm/mmHg). At 30 min reperfusion, the slope was once more significantly decreased (-27.8 +/- 8.1 microm/mmHg). In conclusion, WT in short-term hibernating myocardium is less afterload dependent than in acutely ischemic and reperfused myocardium.

Pulmonary edema in patients after liver transplantation

The aim of this study is to determine the incidence of radiological pulmonary edema in elective liver transplant recipients and its relationship to perioperative factors and postoperative course. We reviewed 102 chest radiographs from 34 patients who had undergone orthotopic liver transplantation (OLT). Films were assessed by 2 trained radiologists for evidence of pulmonary edema using a standardized system. Clinical and outcome data from the 34 patients were also recorded. There was a high incidence (47%) of postoperative radiological pulmonary edema that was associated with deterioration in gaseous exchange, elevated pulmonary artery pressure, and increased duration of ventilator dependence and intensive care stay. Eighteen percent of the patients developed edema immediately after surgery, which was associated with greater pulmonary artery pressure and transfusion requirements during surgery. An additional 29% developed edema during the next 16 to 20 hours, but there was no association with fluid replacement. We conclude that pulmonary edema is common after OLT and will influence postoperative recovery in a substantial proportion of transplant recipients. Excess perioperative fluid replacement is unlikely to be the sole mechanism of edema in these patients.

Symbols and their function in managing the anxiety of change: an intersubjective approach

The author suggests that change inevitably creates anxiety because of loss and confrontation with the unknown. It is proposed that one function of symbols is to manage the anxiety of change. They do this by creating a means by which anxieties can be presented to the subject and then communicated to another mind. These creations are called symbolic because, it is proposed, their purpose is the communication as well as the incorporation of internal anxieties and desires with external exigencies, which might be termed symptoms. Viewing them in this way enables the analyst to put symbolic phenomena as they emerge in an analysis into an intersubjective perspective. The author suggests that thinking of symbols as purely intrasubjective phenomena limits our perspective. It is more technically useful to look at the communicative aspects of symbols as they present themselves to the symbolising subject; and, subsequently, to the analyst in the dialogue within the psychoanalytic setting because the objective and temporal dimension of the setting can thereby be included. Two clinical examples of symbols are discussed, one that was brought for analysis and a second that developed in the course of an analysis. One is given as an example of resistance to change, whereas the other revealed an unconscious drive for change.

Group interventions for anger in people with intellectual disabilities

This paper describes an evaluation of a group intervention for reducing inappropriately expressed anger (as aggression) in people with intellectual disabilities. Group intervention was compared to a treatment as usual group consisting of people referred to the group but who had to wait to participate. The intervention used was based on the work of Novaco (1976; 1978) and Benson (1994). However, further modifications to the group that emphasized the contextual perspective of anger, such as the participants being accompanied by a support worker and more collaborative recording procedures, were devised. A reduction in expressed anger and measured levels of depression occurred after group treatment. Reductions in expressed anger were maintained at 6 and 12 months follow up. However, scores on the depression scale tended to increase on follow up. While caution must be expressed when considering these results, this type of intervention shows promise for reducing inappropriately expressed anger in people with intellectual disabilities Suggestions are made for future research and clinical practice.

Molecular aspects of arrhythmias associated with cardiomyopathies

The increased risk of sudden cardiac death in patients with myocardial hypertrophy and heart failure is the result of remodeling that occurs in both the myocyte and interstitial compartments of the heart. Action potential prolongation is a hallmark of hypertrophied and failing myocardium and is a consequence of differential expression and function of membrane currents and transporters. Functional downregulation of K currents in the ventricle is a recurring theme in hypertrophy and failure; the reduction in the density of the transient outward current (I(to)) is the most consistent observation, whereas data on the density of the inward (I(K1)) and the delayed rectifier (I(K)) currents are more contradictory. The altered intracellular Ca handling of the myopathic hearts prolongs the decay of the L-type Ca current and favors extrusion of cytosolic Ca2+ via the Na+-Ca2+ exchanger. The interaction between such altered membrane currents and a changed neurohumoral milieu creates a substrate that is highly susceptible to potentially lethal ventricular arrhythmias.

Extending the indications for curative liver resection by portal vein embolization

AIMS: The aim of ipsilateral portal vein embolization is to induce hypertrophy of normal tissue when resection of a cancerous portion of the liver is contraindicated only by the volume of liver that would remain following surgery. This study reports its use in primary and metastatic liver tumours. METHODS: Eight patients with inoperable liver tumours (three women and five men of median age 68. 5 years; three colorectal hepatic metastases, two cholangiocarcinomas and three hepatocellular cancers) were selected for portal vein embolization. Selected portal branches were occluded distally with microbeads and proximally with coils. Liver volumes were determined by magnetic resonance imaging before embolization and again before surgery, 6-8 weeks later. RESULTS: Embolization was performed successfully in seven patients by the percutaneous-transhepatic route; one further patient required an open cannulation of the inferior mesenteric vein. Management was altered in six patients, who proceeded to 'curative' surgery. The projected remaining (predominantly left lobe) liver volumes increased significantly from a median of 350 to 550 ml (P < 0.05, Wilcoxon matched pairs test). Two patients had disease progression such that surgery was no longer indicated. One patient, whose disease progressed, had the left portal branch occluded unintentionally by a misplaced coil that was successfully retrieved, although the left portal branch remained occluded. CONCLUSIONS: Portal vein embolization produced significant hypertrophy of the normal liver and extended the option of 'curative' surgery to six of the eight patients in whom it was attempted. It appears to be equally effective for primary and metastatic liver tumours in selected patients.

Nebulised steroid in the treatment of croup: a systematic review of randomised controlled trials

BACKGROUND

Croup is one of the commonest respiratory complaints among children. There is growing evidence that steroids may be an effective treatment.

AIM

To assess the effectiveness of treatment with nebulised steroid for children with croup.

METHOD

Systematic review of randomised controlled trials comparing administration of nebulised steroid with placebo. Trials were identified from searches of three bibliographic databases, the Cochrane Controlled Trials Register, correspondence with the manufacturers of nebulised steroid, and one round of manual citation searching.

RESULTS

Eight randomised controlled trials were identified including 574 children with mild to severe croup. Overall, the mean age was 25.2 months and 72% of children were male. All trials were hospital-based and of good methodological quality, with adequate concealment of treatment allocation and blind outcome assessment. Children treated with nebulised steroid were significantly more likely to show an improvement in croup score by five hours (combined relative risk = 1.48, 95% confidence interval [CI] = 1.27 to 1.74) and significantly less likely to need hospital admission after attending the emergency department (combined relative risk = 0.56, 95% CI = 0.42 to 0.75) than the placebo group. The funnel plot indicated the presence of publication bias, with smaller studies showing the larger effects, but this could also be owing to less pronounced effects in studies of older children with milder croup.

CONCLUSIONS

Nebulised steroids are effective in the treatment of children attending hospital departments with croup. A meta-analysis based on individual patient data could clarify to what extent the effect depends on age and severity of disease. New trials are needed to define the indications for, and effectiveness of, steroid treatment of croup in the community.

Simultaneous X-Ray and TeV Observations of a Rapid Flare from Markarian 421

Mrk 421 was observed for about 2 days with BeppoSAX in 1998 April as part of a worldwide multiwavelength campaign. A large, well-defined flare was observed in X-rays. The same flare was observed simultaneously at TeV energies by the Whipple Observatory gamma-ray telescope. These data provide (1) the first evidence that the X-ray and TeV intensities are well correlated on timescales of hours and (2) the first exactly simultaneous X-ray and TeV spectra. The results imply that the X-ray and TeV photons derive from the same region and from the same population of relativistic electrons. The physical parameters deduced from a homogeneous synchrotron self-Compton model for the spectral energy distribution yield electron cooling times close to the observed variability timescales.

Preparation and preliminary study of crystals of the recombinant calcium-regulated photoprotein obelin from the bioluminescent hydroid Obelia longissima

Crystals of recombinant obelin, the Ca(2+)-regulated photoprotein from the marine hydroid Obelia longissima, have been grown from sodium citrate solutions. Crystals grow as hexagonal light-yellow rods (0.1 x 0.1 x 1.0 mm) which diffract to beyond 1.8 A with synchrotron radiation of 1.0 A wavelength. The crystals have a primitive hexagonal lattice with unit-cell parameters a = 81.55, c = 86.95 A. The asymmetric unit contains two molecules. This represents the successful preparation of single crystals of a photoprotein obelin which have promising diffraction properties.

Role of prolactin in regulating the onset of winter fur growth in mink (Mustela vison): A reconsideration

The objectives of this study were to determine: (1) if the onset of winter hair growth (anagen) in mink could be delayed or inhibited by elevating endogenous PRL concentrations; (2) if bilaterally adrenalectomy (ADX)-induced winter anagen occurs concomitantly with a reduction in serum PRL concentrations, and (3) if exogenous dehydroepiandrosterone (DHEA), an adrenal steroid or Delta(5)-DIOL (a peripherally produced metabolite of DHEA), would delay or inhibit the onset of winter anagen. During early July, while in the resting (telogen) stage of the hair growth cycle, mink were treated with slow release implants containing haloperidol (HAL, a dopaminergic antagonist), melatonin (MEL), deoxycorticosterone (DOC), DHEA and Delta(5)-DIOL. In addition, mink were ADX'd and supplemented with DOC and DHEA. MEL reduced PRL levels to basal levels and induced winter anagen 7 weeks earlier than controls. Surprisingly, HAL initiated winter anagen 7 weeks earlier than controls (P < 0.05), although serum PRL levels were not different between the two groups. Mink that were ADX'd or ADX + DHEA-treated exhibited winter anagen 6 weeks earlier than controls (P < 0.05), but serum PRL concentrations were not different between the three groups. The administration of DHEA or Delta(5)-DIOL to mink with intact adrenals had no effect on the time of onset of winter anagen or serum PRL levels. Our findings suggest that a reduction in circulating PRL levels is not essential for onset of winter anagen in the mink and that the apparent inhibitory effects of the adrenal glands on initiation of winter anagen is not mediated through DHEA or its metabolite Delta(5)-DIOL. J. Exp. Zool. 284:437-444, 1999.