Did the pattern of practice in the prescription of palliative radiotherapy for the treatment of uncomplicated bone metastases change between 1999 and 2005 at the rapid response radiotherapy program?

AIMS

Since 1999, randomised clinical trials and meta-analyses have reported equal efficacy of pain relief from single- and multiple-fraction radiotherapy for bone metastases. A number of factors, including limited radiotherapy resources, waiting times, and patient convenience, suggest single fraction to be the treatment of choice for patients. However, international patterns of practice indicate that multiple fractions are still commonly used. This study examined whether dose-fractionation schemes used for the treatment of bone metastases at the Rapid Response Radiotherapy Program (RRRP) at the Odette Cancer Centre have changed since 1999.

MATERIALS AND METHODS

A retrospective review of the prospective RRRP database and hospital records were conducted for all patients treated with palliative radiotherapy for uncomplicated bone metastases at the RRRP in 1999 (or baseline), 2001, 2004 and from 1 January to 31 July 2005. Data were collected on patient demographics and clinical characteristics.

RESULTS

Of the 693 patients, 65 and 35% were prescribed single fraction (predominantly single 8 Gy) and multiple fractions (predominantly 20 Gy/five fractions), respectively. The administration of single treatments generally increased over time, from 51% in 1999 to 66% in 2005 (P=0.0001). On the basis of multiple logistic regression analyses, patients were more likely to be prescribed single-fraction radiotherapy if they had prostate cancer, had a poorer performance status, were treated to the limbs, hips, shoulders, pelvis, ribs, scapula, sternum, or clavicle (compared with the spine), were treated by a radiation oncologist who had been trained in earlier years, and who were treated after 1999.

CONCLUSIONS

Between 1999 and 2005, the use of single-fraction radiotherapy increased, corresponding to publications showing equal efficacy of pain relief between single and multiple fractions in the management of uncomplicated bone metastases. However, about a third of patients still received multiple fractions.

Amyloid-specific fluorophores for the rapid, sensitive in situ detection of prion contamination on surgical instruments

Prion diseases or transmissible spongiform encephalopathies (TSEs) are a group of rare, transmissible and fatal neurodegenerative diseases associated with the protein agent (PrP(Sc)). As such, the sensitive and rapid detection of prion PrP(Sc) amyloid on the surface of suspect surgical instruments is of great importance and may even allow remedial action to be taken prior to any further operative intervention and possible iatrogenic transmission. However, conventional PrP(Sc) detection methodologies tend to rely on the inefficient and unreliable removal of suspect material from a surface using swabs or wipes prior to antibody analysis. Here we show how the combination of an advanced light microscope technique, episcopic differential interference contrast/epifluorescence (EDIC/EF) microscopy, and the application of beta-amyloid fluorescent thiazole markers (thioflavin T, thioflavin S) can be used to detect, in situ, submicron (attomole) levels of prion protein amyloid contamination in brain and spleen sections, smears and homogenate on surgical stainless steel surfaces and surgical instruments. This technique, although not specific to an amyloid type, can be used to verify that surgical instruments are substantially free from prion amyloid protein soiling and hence reduce the risk of iatrogenic transmission.

Worst, Average or Current Pain in the Brief Pain Inventory: Which Should be Used to Calculate the Response to Palliative Radiotherapy in Patients with Bone Metastases?

AIMS

To determine which pain intensity scale in the Brief Pain Inventory correlates best with functional interference and should be used to calculate the response to palliative radiotherapy. To determine the differences in functional interference scores for patients classified as responders and non-responders to palliative radiotherapy.

PATIENTS AND METHODS

All patients referred to the Rapid Response Radiotherapy Program for palliative radiotherapy of symptomatic bone metastases were considered for the study. Patients rated the intensity and functional interference of their pain at the irradiated sites according to the Brief Pain Inventory before and 2 months after radiotherapy. Worst, average and current pain scores were correlated with functional interference scores using Spearman rank coefficients. Responders and non-responders to palliative radiotherapy were defined for each pain intensity scale according to the end points specified by the International Bone Metastases Consensus Working Party. Average differences between responders and non-responders were compared using a Wilcoxon rank sum test.

RESULTS

Between May 2003 and June 2005, 199 patients enrolled in the study (102 men and 97 women). Ninety-five patients returned complete questionnaires at 2 months of follow-up. All pain intensity and interference scores for evaluable patients were significantly lower at 2 months (P<0.0021). Response rates differed depending on the definition of pain intensity. An overall response rate was observed in 66, 58 and 54% of patients for worst, average and current pain, respectively. Worst pain showed the best correlation with functional interference. Responders reported significantly larger decreases in functional interference scores at follow-up in general activity, normal work, enjoyment of life and average functional interference.

CONCLUSION

Worst pain intensity had higher correlations with all functional interference scores except relationships with others. Therefore, we recommend an 11-point scale measuring worst pain to evaluate response rates in future radiotherapy trials. The mean difference from baseline to follow-up in functional interference scores was significantly larger in patients who responded to radiotherapy treatment.

Functional data analysis applied to a randomized controlled clinical trial in hemodialysis patients describes the variability of patient responses in the control of renal anemia

The achievement of desirable hemoglobin levels in renal anemia that is treated with epoetins is often incomplete and subject to much variation of outcome values and applied dosage. The further development of clinical decision support for renal anemia requires the characterization of patient responses and an analysis of the dynamics of the dosage and response variables. In this methodologic article, the extended data of a randomized, controlled clinical trial comparing two epoetins were examined by the techniques of functional data analysis to establish how precisely the patterns of treatment response might be described and analyzed. The description of the trajectory of hemoglobin values in each patient as a mathematical function allowed the characterization of individual responses, with a wide variety of patterns being revealed. An analysis of the degree of system control in the management of the anemia was then possible through phase plotting. The analysis also allowed an expression of the dynamic characteristics of the entire experimental system, analyzed in summary group waveforms with standard statistical properties. In addition, a quantification of the notional instability of patient responses enabled the determination of a subset of patients for whom control might be improved in a modified management system. It is concluded that functional data analysis does provide the basis for further characterization and experimental study of the control of renal anemia.

The sensitivity of approved Ninhydrin and Biuret tests in the assessment of protein contamination on surgical steel as an aid to prevent iatrogenic prion transmission

Regulations recommend the routine application of biochemical tests, such as the Ninhydrin or Biuret tests, to confirm the efficacy of hospital sterile service department (SSD) washer-disinfector cycles in removing proteinaceous material, particularly with respect to prions. The effectiveness of these methods relies on both the effective sampling of the instruments and the sensitivity of the tests employed. Two commercially available contamination assessment tests were evaluated for their sensitivity to ME7 brain homogenate on surgical-grade stainless steel surfaces. Controls were visualized by the application of episcopic differential interference contrast/Epi-fluorecence microscopy (EDIC/EF) combined with the sensitive fluorescent reagent, SYPRO Ruby, which has been shown previously to rapidly visualize and assess low levels of contamination on medical devices. The Ninhydrin test displayed a minimum level of detection observed by 75% of volunteers (MLD(75)) of 9.25 microg [95% confidence interval (95% CI) 8.6-10.0 microg]. The Biuret test provided better sensitivity, with a MLD(75) of 6.7 microg (95% CI 5.4-8.2 microg). However, much lower concentrations of proteinaceous soiling (pg) were visualized using the EDIC/EF microscopy method. From these findings, it is clear that these approved colorimetric tests of cleaning are relatively insensitive. This investigation demonstrates how large amounts (up to 6.5 microg) of proteinaceous brain contamination could remain undetected and the instruments deemed clean using such methods. The application of more sensitive cleanliness evaluation methods should be applied to reduce the risk of iatrogenic transmission of prion disease in 'high-risk' instruments such as neurosurgical devices.

Are surgical stainless steel wires used for intracranial implantation of PrPsc a good model of iatrogenic transmission from contaminated surgical stainless steel instruments after cleaning?

Transmissible spongiform encephalopathies are a group of fatal, neurodegenerative diseases commonly known as prion diseases. Prion diseases can resist traditional inactivation strategies and may be iatrogenically transmitted by surgical instruments through the human population. These properties have led to the need for a suitable detection method of the prion infectious agent, and increased pressure regarding the development of anti-prion cleaning methodologies that would ensure the safety of surgical instruments. Although other techniques have been applied, the animal bioassay remains the 'gold standard' method for assessing infectivity. As the vast majority of surgical instruments are made of stainless steel, and in order to test this surface using the animal bioassay, the application of very thin surgical stainless steel wires has been widely adopted. These wires are easily inoculated and may be reimplanted into animals without the requirement for elution of the residual material. However, their comparability to the dimensions, shape and size of surgical instruments is questionable. This article shows how such contaminated wires (residual protein between 6.3 and 16.0 ng/mm(2)) can be cleaned more easily than flat metal surfaces (residual protein between 63.9 and 89.3 ng/mm(2)) under comparable conditions using recommended cleaning agents. These results indicate that the application of wires as a realistic means of assessing the removal or inactivation of the prion infectious agent from surgical instruments should be treated with caution.

Validation of the use of organic acids and acidified sodium chlorite to reduce Escherichia coli O157 and Salmonella typhimurium in beef trim and ground beef in a simulated processing environment

A study was conducted to determine if acidified sodium chlorite (1,200 ppm) and acetic and lactic acids (2 and 4%) were effective in reducing foodborne pathogens in beef trim prior to grinding in a simulated processing environment. The reduction of Salmonella Typhimurium and Escherichia coli O157:H7 at high (4.0 log CFU/g) and low (1.0 log CFU/g) inoculation doses was evaluated at various processing steps, including the following: (i) in trim just after treatment application, (ii) in ground beef just after grinding, (iii) in ground beef 24 h after refrigerated storage, (iv) in ground beef 5 days after refrigerated storage, and (v) in ground beef 30 days after frozen storage. All antimicrobial treatments reduced the pathogens on the trim inoculated with the lower inoculation dose to nondetectable numbers in the trim and in the ground beef. There were significant reductions of both pathogens in the trim and in the ground beef inoculated with the high inoculation doses. On the trim itself, E. coli O157:H7 and Salmonella Typhimurium were reduced by 1.5 to 2.0 log cycles, with no differences among all treatments. In the ground beef, the organic acids were more effective in reducing both pathogens than the acidified sodium chlorite immediately after grinding, but after 1 day of storage, there were no differences among treatments. Overall, in the ground beef, there was a 2.5-log reduction of E. coli O157:H7 and a 1.5-log reduction of Salmonella Typhimurium that was sustained over time in refrigerated and frozen storage. Very few sensory differences between the control samples and the treated samples were detected by a consumer panel. Thus, antimicrobial treatments did not cause serious adverse sensory changes. Use of these antimicrobial treatments can be a promising intervention available to ground beef processors who currently have few interventions in their process.

Evaluation of the HER2/neu-derived peptide GP2 for use in a peptide-based breast cancer vaccine trial

BACKGROUND

E75 and GP2 are human leukocyte antigen (HLA)-A2-restricted immunogenic peptides derived from the HER2/neu protein. In a E75 peptide-based vaccine trial, preexisting immunity and epitope spreading to GP2 was detected. The purpose of this study was to further investigate GP2 for potential use in vaccination strategies. Importantly, a naturally occurring polymorphism (I-->V at position 2, 2VGP2) associated with increased breast cancer risk was addressed.

METHODS

Prevaccination peripheral blood samples (PBMC) from HLA-A2 breast cancer patients and CD8+ T cells from HLA-A2 healthy donors were stimulated with autologous dendritic cells (DC) pulsed with GP2 and tested in standard cytotoxicity assays with HER2/neu+ tumor cells or GP2- or 2VGP2-loaded T2 targets. Additional cytotoxicity experiments used effectors stimulated with DC pulsed with E75, GP2, or the combination of E75+GP2.

RESULTS

GP2-stimulated prevaccination PBMC from 28 patients demonstrated killing of MCF-7, SKOV3-A2, and the HLA-A2- control target SKOV3 of 28.8+/-3.7% (P<.01), 29.5+/-4.0% (P<.01), and 16.9+/-2.7%, respectively. When compared with E75, GP2-stimulated CD8+ T cells lysed HER2/neu+ targets at 43.8+/-5.2% versus 44.2+/-5.7% for E75 (P=.87). When combined, an additive effect was noted with 58.6+/-5.4% lysis (P=.05). GP2-stimulated CD8+ T cells specifically recognized both GP2-loaded (19.6+/-5.7%) and 2VGP2-loaded T2 targets (17.7+/-5.2%).

CONCLUSIONS

GP2 is a clinically relevant HER2/neu-derived peptide with immunogenicity comparable to that of E75. Importantly, GP2-specific effectors recognize 2VGP2-expressing targets; therefore, a GP2 vaccine should be effective in patients carrying this polymorphism. GP2 may be most beneficial used in a multiepitope vaccine.

Ultra-fast three dimensional imaging of hyperpolarized 13C in vivo

OBJECTIVE

PASADENA, a chemical method of enhancing nuclear spin polarization has demonstrated 13C polarizations of order unity for the nascent products of molecular addition by parahydrogen. The extreme brevity of signal enhancement obtained by hyperpolarization requires improved 13C MR in vivo imaging techniques for their optimum utility.

MATERIALS AND METHODS

13C imaging sequences, including 13C 3D FIESTA, were compiled for a GE LX 1.5 T clinical MR scanner. Two water soluble 13C imaging agents were hyperpolarized utilizing parahydrogen and an automated polarizer. 13C polarization was quantified in flow phantoms and in rats with jugular vein catheters.

RESULTS

Fast 3D FIESTA 13C MR imaging technique acquired sequential 3D images (3.66 s/acquisition) with superior SNR. Hyperpolarized 13C solutions and vascular phantoms achieved a maximum signal of 26,624+/-593. In vivo 13C MR images of the cardiopulmonary circulation showed maximum 13C signal of 2,402+/-158. 13C images acquired within 3.66 s showed signal enhancement over 10,000 compared to equilibrium polarization.

CONCLUSION

3D-FIESTA was effective for sub-second in vivo imaging of hyperpolarized 13C reagents produced in a custom-built parahydrogen polarizer. Application to 13C hyperpolarized by parahydrogen is demonstrated in vitro and in vivo.

Reduction of Escherichia coli O157:H7 and Salmonella in ground beef using lactic acid bacteria and the impact on sensory properties

Studies were conducted to determine whether four strains of lactic acid bacteria (LAB) inhibited Escherichia coli O157: H7 and Salmonella in ground beef at 5 degrees C and whether these bacteria had an impact on the sensory properties of the beef. The LAB consisted of frozen concentrated cultures of four Lactobacillus strains, and a cocktail mixture of streptomycin-resistant E. coli O157:H7 and Salmonella were used as pathogens. Individual LAB isolates at 10(7) CFU/ml were added to tryptic soy broth containing a pathogen concentration of 10(5) CFU/ml. Samples were stored at 5 degrees C, and pathogen populations were determined on days 0, 4, 8, and 12. After 4 days of storage, there were significant differences in numbers of both pathogens exposed to LAB isolates NP 35 and NP 3. After 8 and 12 days of storage, all LAB reduced populations of both pathogens by an average of 3 to 5 log cycles. A second study was conducted in vacuum-packaged fresh ground beef. The individual LAB isolates resulted in an average difference of 1.5 log cycles of E. coli O157:H7 after 12 days of storage, and Salmonella populations were reduced by an average of 3 log cycles. Following this study, a mixed concentrated culture was prepared from all four LAB and added to ground beef inoculated with pathogen at 10(8) CFU/g. After 3 days of storage, the mixed culture resulted in a 2.0-log reduction in E. coli O157:H7 compared with the control, whereas after 5 days of storage, a 3-log reduction was noted. Salmonella was reduced to nondetectable levels after day 5. Sensory studies on noninoculated samples that contained LAB indicated that there were no adverse effects of LAB on the sensory properties of the ground beef. This study indicates that adding LAB to raw ground beef stored at refrigeration temperatures may be an important intervention for controlling foodborne pathogens.

Plasma levobupivacaine concentrations following scalp block in patients undergoing awake craniotomy

BACKGROUND

Levobupivacaine is an effective local anaesthetic agent for nerve blockade with less systemic toxicity than racemic bupivacaine. The safety and efficacy of levobupivacaine for scalp blockade during awake craniotomy have not been addressed previously.

METHODS

Serial arterial plasma levobupivacaine concentrations following scalp blockade were measured to 2 h in 10 patients booked for awake craniotomy for epilepsy or tumour surgery. Bilateral scalp blockade providing surgical anaesthesia was achieved with a mean dose of 177 mg (2.5 mg kg(-1), range 1.6-3.2 mg kg(-1)) of levobupivacaine (0.5%, 5 mg ml(-1)) with epinephrine (5 microg ml(-1)) added immediately before the block insertion.

RESULTS

The maximum measured plasma levobupivacaine concentration was 1.58 (0.44) microg ml(-1) [mean (SD)] with a mean time to peak plasma concentration of 12 (4) min. There were no episodes in any of the 10 patients of symptoms or signs suggestive of either CNS or CVS toxicity.

CONCLUSIONS

This study demonstrated a relatively rapid rise of plasma levobupivacaine concentration without evidence of cardiovascular or central nervous system sequelae in a sample population of patients who may be particularly prone to perioperative seizures.

Quantitative measures of cluster quality for use in extracellular recordings

While the use of multi-channel electrodes (stereotrodes and tetrodes) has allowed for the simultaneous recording and identification of many neurons, quantitative measures of the quality of neurons in such recordings are lacking. In multi-channel recordings, each spike waveform is discriminated in a high-dimensional space, making traditional measures of unit quality inapplicable. We describe two measures of unit isolation quality, Lratio and Isolation Distance, and evaluate their performance using simulations and tetrode recordings. Both measures quantified how well separated the spikes of one cluster (putative neuron) were from other spikes recorded simultaneously on the same multi-channel electrode. In simulations and tetrode recordings, both Lratio and Isolation Distance discriminated well- and poorly-separated clusters. In data sets from the rodent hippocampus in which neurons were simultaneously recorded intracellularly and extracellularly, values of Isolation Distance and Lratio were related to the correct identification of spikes.

Nociceptin/orphanin FQ modulation of ionic conductances in rat basal forebrain neurons

Nociceptin/orphanin FQ (N/OFQ) is an endogenous opioid-like heptadecapeptide that plays an important role in a variety of physiological functions. N/OFQ and its receptor opioid receptor-like orphan receptor-1 are abundant in the diagonal band of Broca (DBB), a basal forebrain nucleus where the loss of cholinergic neurons is linked to memory and spatial learning deficits. In the whole animal, central injections of N/OFQ have been shown to disrupt spatial learning. In this study, we investigated the basis for these behavioral observations by examining the cellular effects of N/OFQ on chemically identified DBB neurons. Whole cell patch-clamp recordings were performed on enzymatically dissociated DBB neurons. Under voltage-clamp conditions, bath application of N/OFQ (10 pM-1 microM) resulted in a dose-dependent depression of whole cell currents. Single cell reverse transcription-polymerase chain reaction analysis identified cholinergic and fewer GABAergic cells to be N/OFQ-responsive. [Nphe(1)]nociceptin-(1-13)-NH(2) and CompB (J-113397) antagonized the N/OFQ response, but both compounds also displayed partial agonist activity. Using a combination of channel blockers we determined that the effects of N/OFQ were mediated via a suite of Ca(2+) (N- and L-type) and Ca(2+)-dependent K(+) (iberiotoxin-sensitive) conductances. In addition, biophysical analysis of voltage subtraction protocols revealed that N/OFQ reduces transient outward and the delayed rectifier K(+) currents. Because N-type and L-type Ca(2+) channels are important in the context of neurotransmitter release, our observations indicate that N/OFQ inhibition of Ca(2+)-dependent conductances in cholinergic neurons would be expected to result in depression of acetylcholine release, which may explain the behavioral actions of N/OFQ in the brain.

Inspired CO(2) and O(2) in sleeping infants rebreathing from bedding: relevance for sudden infant death syndrome

Some infants sleep facedown for long periods with no ill effects, whereas others become hypoxemic. Rebreathing of expired air has been determined by CO(2) measurement; however, O(2) levels under such conditions have not been determined. To evaluate this and other factors influencing inspired gas concentrations, we studied 21 healthy infants during natural sleep while facedown on soft bedding. We measured gas exchange with the environment and bedding, ventilatory response to rebreathing, and concentrations of inspired CO(2) and O(2). Two important factors influencing inspired gas concentrations were 1) a variable seal between bedding and infants' faces and 2) gas gradients in the bedding beneath the infants, with O(2)-poor and CO(2)-rich air nearest to the face, fresher air distal to the face, and larger tidal volumes being associated with fresher inspired air. Minute ventilation increased significantly while rebreathing because of an increase in tidal volume, not frequency. The measured drop in inspired O(2) was significantly greater than the accompanying rise in inspired CO(2). This appears to be due to effects of the respiratory exchange ratio and differential tissue solubilities of CO(2) and O(2) during unsteady conditions.

Role of scaffolds in MAP kinase pathway specificity revealed by custom design of pathway-dedicated signaling proteins

BACKGROUND

Signal transduction pathways with shared components must be insulated from each other to avoid the inappropriate activation of multiple pathways by a single stimulus. Scaffold proteins are thought to contribute to this specificity by binding select substrates.

RESULTS

We have studied the ability of scaffold proteins to influence signaling by the yeast kinase Ste11, a MAPKKK molecule that participates in three distinct MAP kinase pathways: mating, filamentation, and HOG. We used protein fusions to force Ste11 to associate preferentially with a subset of its possible binding partners in vivo, including Ste5, Ste7, and Pbs2. Signaling became confined to a particular pathway when Ste11 was covalently attached to these scaffolds or substrates. This pathway bias was conferred upon both stimulus-activated and constitutively active forms of Ste11. We also used membrane-targeted derivatives of the mating pathway scaffold, Ste5, to show that stimulus-independent signaling initiated by this scaffold remained pathway specific. Finally, we demonstrate that loss of pathway insulation has a negative physiological consequence, as nonspecific activation of both the HOG and mating pathways interfered with proper execution of the mating pathway.

CONCLUSIONS

The signaling properties of these kinase fusions support a model in which scaffold proteins dictate substrate choice and promote pathway specificity by presenting preferred substrates in high local concentration. Furthermore, insulation is inherent to scaffold-mediated signaling and does not require that signaling be initiated by pathway-specific stimuli or activator proteins. Our results give insight into the mechanisms and physiological importance of pathway insulation and provide a foundation for the design of customized signaling proteins.

The effects of an ACE inhibitor and a calcium antagonist on the progression of renal disease: the Nephros Study

BACKGROUND

The renoprotective effect of ACE inhibition in chronic renal disease is well established but the studies on effects of calcium antagonists on progression of renal disease and on proteinuria have given varying results.

METHODS

We conducted an open long-term randomized prospective multi-centre study comparing the combination of ramipril and felodipine ER (F) with either drug alone in non-diabetic renal disease. Included were patients with uncontrolled hypertension (diastolic blood pressure (DBP)) > or =95 mmHg on treatment with a diuretic and a beta-blocker. Fifty-one patients received the combination of R and F, 54 patients R, and 53 patients F. The treatment goal was a DBP <90 mmHg and a similar BP reduction in the three groups. Mean doses at the last visit were 5+5, 10 and 9 mg, respectively, after a mean treatment time of nearly 2 years. The progression of renal impairment was studied by serial measurements of serum creatinine, iohexol clearance, and albuminuria.

RESULTS

The reduction in supine systolic (S) BP and DBP expressed as median values were -19.0/-14.5,-14.3/-15.0 and -13.5/-13.3 mmHg in the R+F, R, and F groups, respectively. There was no significant difference between the groups. When correction for the acute drug effect was performed the R+F group had a slower progression rate of the renal disease (loss of glomerular filtration rate (GFR) ml/min/year) compared with the F group (P<0.05) but not to the R group (P>0.20). There was a rise in albuminuria after 2 years in the F group (P<0.05), but no significant change was found in the other groups.

CONCLUSIONS

In patients with non-diabetic renal disease the combination of an ACE inhibitor and a calcium antagonist in reduced doses used in addition to baseline therapy with beta-blockers and diuretics, tended to cause a better BP reduction as each drug per se. The R+F treatment also caused a slower progression of the renal disease compared with F alone. The combination treatment seems to afford better BP control and appears to be a favourable therapeutic option in patients with renal disease and hypertension.

Predictors of length of stay after coronary stenting

BACKGROUND

Postprocedure length of stay (LOS) remains an important determinant of medical costs after coronary stenting. Variables that predict LOS in this setting have not been well characterized.

METHODS

We evaluated 359 consecutive patients who underwent coronary stenting with antiplatelet therapy. Sequential multiple linear regression (MLR) models were constructed with use of 4 types of variables to predict log-transformed LOS: preprocedure, intraprocedure, and postprocedure factors and adverse outcomes.

RESULTS

Preprocedure factors alone explained more than one third of the variability in postprocedure LOS (adjusted R(2) = 0.37). The addition of procedural variables added little to the model (adjusted R(2) = 0.39). Entering nonoutcome postprocedure variables significantly enhanced the predictive capacity of the model, explaining more than half the variability in postprocedure LOS (adjusted R(2) = 0.54). In the final model, addition of outcome variables increased its predictive capacity only slightly (adjusted R(2) = 0.61). In this model, significant preprocedure factors included: myocardial infarction (MI) within 24 hours, MI within 1 to 30 days, women with peripheral vascular disease, intravenous heparin, and chronic atrial fibrillation. High-risk intervention was the only significant intraprocedure variable. Significant postprocedure factors included periprocedure ischemia; cerebrovascular accident or transient ischemic attack; treatment with intravenous heparin or nitroglycerin or intra-aortic balloon pump; and need for blood transfusion. Significant adverse outcomes included contrast nephropathy, gastrointestinal bleeding, arrhythmia, vascular complication, and repeat angiography.

CONCLUSION

This prediction model identifies a number of potentially reversible factors responsible for prolonging LOS and may enable the development of more accurate risk-adjusted methods with which to improve or compare care.

Three-dimensional MR pulmonary perfusion imaging and angiography with an injection of a new blood pool contrast agent B-22956/1

Initial evaluation of a new blood pool agent, B-22956/1, for pulmonary imaging was performed in five domestic pigs with artificial embolism. Pre-embolism 3D pulmonary perfusion images were first acquired by injecting an extravascular agent, gadoteridol. The pulmonary arteries of the pigs were then occluded by the artificial emboli. Post-embolism perfusion scans were subsequently performed by injecting B-22956/1. Additional post-embolism high-spatial-resolution angiograms were also acquired. Parenchyma perfusion deficits were well depicted in the post-embolism perfusion maps. The post-embolism angiography clearly revealed the location and extent of the filling defects in the pulmonary vessels. Signal intensities of perfusion maps on the normal parenchyma were significantly improved (30%) by using B-22956/1, in comparison with perfusion images using gadoteridol (P < 0.01). Many pulmonary angiograms with approximately equal contrast could be obtained even at 22 minutes after the injection of B-22956/1. Our initial results indicate that blood pool agent B-22956/1 may provide opportunities for whole-lung-coverage perfusion mapping and additional high-resolution target angiograms after a single injection.

Contrast-enhanced coronary MR angiography: relationship between coronary artery delineation and blood T1

Contrast-enhanced coronary angiography has become an important technique for magnetic resonance (MR) coronary artery imaging. However, the relationship between the quality of the coronary artery images and blood T1 has not yet been fully explored. In this paper, we assessed this relationship in an animal model by using a prototypical blood pool agent. With accumulated injections of this agent, the blood T1 would be maintained at different levels. The measured blood T1 values in vivo were 147 +/- 3, 82 +/- 6, 48 +/- 4, 40 +/- 3, and 30 +/- 8 msec (N = 7). Fixed and variable flip angle schemes were used in coronary artery imaging. The signal to noise ratios (SNR) of coronary arteries were measured and the image quality was assessed. It was found that blood T1 less than 80 msec might be desired. No statistically significant difference was observed between two flip angle schemes. There was better vessel definition using variable flip angle at blood T1 lower than 50 msec. Understanding this relationship may be beneficial to optimizing image protocol and/or design of blood pool contrast agents for contrast-enhanced coronary angiography.

Cellular mechanisms for amyloid beta-protein activation of rat cholinergic basal forebrain neurons

The deposition of amyloid beta-protein (Abeta) in the brain and the loss of cholinergic neurons in the basal forebrain are two pathological hallmarks of Alzheimer's disease (AD). Although the mechanism of Abeta neurotoxicity is unknown, these cholinergic neurons display a selective vulnerability when exposed to this peptide. In this study, application of Abeta(25-35) or Abeta(1-40) to acutely dissociated rat neurons from the basal forebrain nucleus diagonal band of Broca (DBB), caused a decrease in whole cell voltage-activated currents in a majority of cells. This reduction in whole cell currents occurs through a modulation of a suite of potassium conductances including calcium-activated potassium (I(C)), the delayed rectifier (I(K)), and transient outward potassium (I(A)) conductances, but not calcium or sodium currents. Under current-clamp conditions, Abeta evoked an increase in excitability and a loss of accommodation in cholinergic DBB neurons. Using single-cell RT-PCR technique, we determined that Abeta actions were specific to cholinergic, but not GABAergic DBB neurons. Abeta effects on whole cell currents were occluded in the presence of membrane-permeable protein tyrosine kinase inhibitors, genistein and tyrphostin B-44. Our data indicate that the Abeta actions on specific potassium conductances are modulated through a protein tyrosine kinase pathway and that these effects are selective to cholinergic but not GABAergic cells. These observations provide a cellular basis for the selectivity of Abeta neurotoxicity toward cholinergic basal forebrain neurons that are at the epicenter of AD pathology.

Initial sequencing and analysis of the human genome

The human genome holds an extraordinary trove of information about human development, physiology, medicine and evolution. Here we report the results of an international collaboration to produce and make freely available a draft sequence of the human genome. We also present an initial analysis of the data, describing some of the insights that can be gleaned from the sequence.

Thoracic lymphatic pumping and the efficacy of influenza vaccination in healthy young and elderly populations

The authors investigated whether thoracic lymphatic pumping (TLP) after FluShield vaccination enhanced the production of anti-influenza immunoglobulins in elderly individuals, who are at particular risk for influenza. Osteopathic students and non-TLP-treated elderly subjects served as controls. Serum antibody titers were quantified with enzyme-linked immunosorbent assay, and hemagglutination inhibition assay, both of which generated comparable results. While approximately 70% of the younger controls had increased anti-influenza immunoglobulin production on vaccination, only 30% to 35% of the aged population had increased antibody production. There was no significant enhancement in anti-influenza immunoglobulin production in the TLP-treated subjects. The authors' findings suggest that TLP in conjunction with influenza vaccination does not enhance immunization against influenza in otherwise healthy and active populations. However, such techniques may be of value when applied in conjunction with vaccination to nonambulatory patients or on actual influenza exposure of at-risk individuals.

A T-cell-selective interleukin 2 mutein exhibits potent antitumor activity and is well tolerated in vivo

Human interleukin 2 (IL-2; Proleukin) is an approved therapeutic for advanced-stage metastatic cancer; however, its use is restricted because of severe systemic toxicity. Its function as a central mediator of T-cell activation may contribute to its efficacy for cancer therapy. However, activation of natural killer (NK) cells by therapeutically administered IL-2 may mediate toxicity. Here we have used targeted mutagenesis of human IL-2 to generate a mutein with approximately 3,000-fold in vitro selectivity for T cells over NK cells relative to wild-type IL-2. We compared the variant, termed BAY 50-4798, with human IL-2 (Proleukin) in a therapeutic dosing regimen in chimpanzees, and found that although the T-cell mobilization and activation properties of BAY 50-4798 were comparable to human IL-2, BAY 50-4798 was better tolerated in the chimpanzee. BAY 50-4798 was also shown to inhibit metastasis in a mouse tumor model. These results indicate that BAY 50-4798 may exhibit a greater therapeutic index than IL-2 in humans in the treatment of cancer and AIDS.

Statins and cardiovascular diseases: the multiple effects of lipid-lowering therapy by statins

Cholesterol lowering involving different therapies improves the clinical outcome of patients. To define the underlying pathomechanism, we studied whether treatment with statins was associated with changes in blood thrombogenicity, endothelial dysfunction and soluble adhesion molecule levels. Fifty hypercholesterolemic patients were treated with pravastatin (40 mg/day, n=24) or simvastatin (20 mg/day, n=26). Lipid profile and blood thrombogenicity were assessed in all patients before and after 3 months of cholesterol reducing therapy. Blood thrombogenicity was assessed as thrombus formation, perfusing non-anticoagulated blood directly from the patients' vein through the Badimon perfusion chamber (shear rate 1690/s). Endothelial-dependent vasomotor response was tested by laser-Doppler flowmeter. Soluble adhesion molecule level were measured by ELISA. Total and LDL cholesterol were reduced in the two treatment groups by statin therapy. Statin therapy was associated with a significant reduction in blood thrombogenicity and endothelium-dependent vasoresponse. No differences were observed between simvastatin or pravastatin treatment. Lipid lowering by statins had no effect on plasma levels of fibrinogen, sL-selectin, sP-selectin and sICAM-1 antigen. Cholesterol lowering by both statins reduced the increased blood reactivity and endothelial dysfunction present under hypercholesterolemia. The multiple effects of lipid lowering therapy by statins may explain the benefits observed in recent epidemiological trials.

Measuring the self-esteem of adolescents with mental health problems: theory meets practice

Occupational therapists frequently address the self-esteem of young clients despite little empirical evidence that the clients have low self-esteem to begin with, and that occupational therapy intervention is effective in addressing self-esteem. This article examines the self-esteem of 39 adolescents with mental health problems referred to a pre-vocational programme in an effort to compare clinical practice with empirical findings. The Self-Perception Profile for Adolescents and the Importance Rating Scale for Adolescents are employed to compare the self-esteem of the adolescents with mental health problems with the normative sample, prior to (n = 39) and upon completion of the pre-vocational programme (n = 14). Results indicate no difference between the two groups' self-esteem and no change in self-esteem scores following participation in the pre-vocational programme. Global self-esteem is significantly correlated with physical appearance and behavioural conduct (n = 39). Competence-importance discrepancy scores are significantly related to global self-esteem (n = 14). This finding supports the theory that it is the domain of self-concept which is low and important to the adolescent which will influence his/her self-esteem. These results are consistent with previous studies. Possible explanations for the discrepancy between clinical perceptions and objective findings are discussed. Implications for practice are presented.

The N terminus of the centromere H3-like protein Cse4p performs an essential function distinct from that of the histone fold domain

Cse4p is an evolutionarily conserved histone H3-like protein that is thought to replace H3 in a specialized nucleosome at the yeast (Saccharomyces cerevisiae) centromere. All known yeast, worm, fly, and human centromere H3-like proteins have highly conserved C-terminal histone fold domains (HFD) but very different N termini. We have carried out a comprehensive and systematic mutagenesis of the Cse4p N terminus to analyze its function. Surprisingly, only a 33-amino-acid domain within the 130-amino-acid-long N terminus is required for Cse4p N-terminal function. The spacing of the essential N-terminal domain (END) relative to the HFD can be changed significantly without an apparent effect on Cse4p function. The END appears to be important for interactions between Cse4p and known kinetochore components, including the Ctf19p/Mcm21p/Okp1p complex. Genetic and biochemical evidence shows that Cse4p proteins interact with each other in vivo and that nonfunctional cse4 END and HFD mutant proteins can form functional mixed complexes. These results support different roles for the Cse4p N terminus and the HFD in centromere function and are consistent with the proposed Cse4p nucleosome model. The structure-function characteristics of the Cse4p N terminus are relevant to understanding how other H3-like proteins, such as the human homolog CENP-A, function in kinetochore assembly and chromosome segregation.

A needs assessment in a refugee mental health project in north-east London: extending the counselling model to community support

In the United Kingdom, as elsewhere, mental health services are becoming increasingly aware that existing services may not meet the needs of different minority groups. This paper outlines the model used to set up a project focusing specifically on refugee mental health needs in Waltham Forest, in north-east London. Funding was available for one sole mental health worker and careful consideration was therefore given as to how her time should be used. A thorough needs assessment of refugees living in Waltham Forest determined that the provision of therapy or counselling alone would not be the most appropriate means of addressing refugees' needs. The intervention model developed therefore included awareness raising and community mobilization, in addition to one-to-one clinical sessions. The empowerment, training and support of refugee community groups became a central part of the work, which helped to establish and then consolidate links between mainstream services and individual refugees.

An agenda for research into uterine artery embolization: results of an expert panel conference

PURPOSE

To develop a research agenda for uterine artery embolization (UAE) for the treatment of symptomatic leiomyomata.

MATERIALS AND METHODS

An expert panel was convened to examine data and develop a consensus for UAE research. Panelists reviewed data from articles about UAE and data on hysterectomy and myomectomy, which were abstracted into evidence tables. A modified Delphi process was used to rate the importance of measuring specific outcomes and a nominal group process was used to develop ideas for study designs.

RESULTS

Panelists agreed that UAE studies would have to examine certain key measures. Outcomes identified as either "important to measure" or "essential to measure" were death, reoperation, operative injury, menorrhagia, premature menopause, recurrence of myomata, and satisfaction. The panel proposed four areas for research: randomized trial, prospective registry, disease-specific quality-of-life instrument, and cost analysis.

CONCLUSIONS

Symptomatic uterine leiomyomata are a major health concern for women. New techniques that promise to provide symptom relief deserve careful consideration. Traditionally, surgical procedures have been poorly studied until after they have been widely used. If the process described in this article can guide the acquisition of knowledge in this field, it may serve as a model for evaluating other new technologies before they become widely adopted.

Effect of recombinant SP-C surfactant in a porcine lavage model of acute lung injury

Synthetic surfactants allow examination of the effects of specific components of natural surfactant. To determine whether surfactant containing apoprotein C, dipalmitoyl-phosphatidylcholine, phosphatidylglycerol, and palmitic acid restores gas-exchanging function in acute lung injury (ALI), we administered such surfactant (in doses of 50 or 100 mg/kg and in volumes from 1 to 6 ml/kg) or phospholipid (PL) alone, by intratracheal instillation, to pigs with ALI induced by massive saline lavage. Animals ventilated with 100% O(2) and receiving 1, 2, 4, or 6 ml/kg of 50 mg/kg recombinant surfactant apoprotein C (rSP-C) surfactant or 2 ml/kg of 50 mg/kg PL (control) had mean arterial PO(2) values, 4 h after treatment, of 230, 332, 130, 142, or 86 Torr, respectively. Animals receiving 1, 2, or 4 ml/kg of 100 mg/kg rSP-C surfactant or 2 ml/kg of 100 mg/kg PL (control) had mean arterial PO(2) values of 197, 214, 148, or 88 Torr, respectively. Surfactant PL distribution was homogeneous. Hyaline membrane formation was reduced in treated animals. Thus, in this model of ALI, rSP-C with PL has the capacity to improve gas exchange and possibly modify lung injury.

Hepatitis C virus-associated oral lichen planus: no influence from hepatitis G virus co-infection

There is a variable geographic distribution in the prevalence of hepatitis C virus (HCV)-related oral lichen planus (OLP), which appears unrelated to either HCV genotype or HCV epidemiology. The present study investigated whether hepatitis G virus (HGV) co-infection may be a feature of patients with HCV-related OLP, which might explain these phenomena. HGV co-infection was detected in 6 of 39 Italian patients with HCV-related OLP, but the presence of HGV did not influence the clinical presentation of OLP. It is concluded that HGV co-infection is unlikely to influence the clinical detection of HCV-related OLP.

Relationship of MRI delayed contrast enhancement to irreversible injury, infarct age, and contractile function

BACKGROUND

Contrast MRI enhancement patterns in several pathophysiologies resulting from ischemic myocardial injury are controversial or have not been investigated. We compared contrast enhancement in acute infarction (AI), after severe but reversible ischemic injury (RII), and in chronic infarction.

METHODS AND RESULTS

In dogs, a large coronary artery was occluded to study AI and/or chronic infarction (n = 18), and a second coronary artery was chronically instrumented with a reversible hydraulic occluder and Doppler flowmeter to study RII (n = 8). At 3 days after surgery, cine MRI revealed reduced wall thickening in AI (5+/-6% versus 33+/-6% in normal, P<0.001). In RII, wall thickening before, during, and after inflation of the occluder for 15 minutes was 35+/-5%, 1+/-8%, and 21+/-10% and Doppler flow was 19.8+/-5.3, 0.2+/-0.5, and 56.3+/-17.7 (peak hyperemia) cm/s, respectively, confirming occlusion, transient ischemia, and reperfusion. Gd-DTPA-enhanced MR images acquired 30 minutes after contrast revealed hyperenhancement of AI (294+/-96% of normal, P<0.001) but not of RII (98+/-6% of normal, P = NS). Eight weeks later, the chronically infarcted region again hyperenhanced (253+/-54% of normal, n = 8, P<0.001). High-resolution (0.5 x 0.5 x 0.5 mm) ex vivo MRI demonstrated that the spatial extent of hyperenhancement was the same as the spatial extent of myocyte necrosis with and without reperfusion at 1 day (R = 0.99, P<0.001) and 3 days (R = 0.99, P<0.001) and collagenous scar at 8 weeks (R = 0.97, P<0.001).

CONCLUSIONS

In the pathophysiologies investigated, contrast MRI distinguishes between reversible and irreversible ischemic injury independent of wall motion and infarct age.