Determining the impact of an artificial intelligence tool on the management of pulmonary nodules detected incidentally on CT (DOLCE) study protocol: a prospective, non-interventional multicentre UK study

INTRODUCTION

In a small percentage of patients, pulmonary nodules found on CT scans are early lung cancers. Lung cancer detected at an early stage has a much better prognosis. The British Thoracic Society guideline on managing pulmonary nodules recommends using multivariable malignancy risk prediction models to assist in management. While these guidelines seem to be effective in clinical practice, recent data suggest that artificial intelligence (AI)-based malignant-nodule prediction solutions might outperform existing models.

METHODS AND ANALYSIS

This study is a prospective, observational multicentre study to assess the clinical utility of an AI-assisted CT-based lung cancer prediction tool (LCP) for managing incidental solid and part solid pulmonary nodule patients vs standard care. Two thousand patients will be recruited from 12 different UK hospitals. The primary outcome is the difference between standard care and LCP-guided care in terms of the rate of benign nodules and patients with cancer discharged straight after the assessment of the baseline CT scan. Secondary outcomes investigate adherence to clinical guidelines, other measures of changes to clinical management, patient outcomes and cost-effectiveness.

ETHICS AND DISSEMINATION

This study has been reviewed and given a favourable opinion by the South Central-Oxford C Research Ethics Committee in UK (REC reference number: 22/SC/0142).Study results will be available publicly following peer-reviewed publication in open-access journals. A patient and public involvement group workshop is planned before the study results are available to discuss best methods to disseminate the results. Study results will also be fed back to participating organisations to inform training and procurement activities.

TRIAL REGISTRATION NUMBER

NCT05389774.

First medical contact facility type as a determinant of prognosis in a regional ST elevation myocardial infarction network

Background

Delay in primary percutaneous coronary intervention (PPCI) in ST elevation myocardial infartion (STEMI) is associated with worse prognosis. In our regional STEMI network, the first medical contact (FMC) facility type defines 4 different assistance pathways (i.e. emergency medical services'diagnosis on the field and direct transfer to the catheterization laboratory (cath. lab) of a PCI hospital (EMS group); direct admission to a PCI hospital (PCI-H group); admission to community hospital and transfer to the cath lab of the PCI-H (CH group); diagnosis in a primary care centre and transfer to the cath lab of the PCI-H (PCC group). Each different FMC has been associated with different degrees in reperfusion delay.

Objective

To determine the influence of FMC facility type on 1-year mortality in patients with STEMI in our regional STEMI network.

Methods

This is a retrospective study based on the STEMI network registry, a mandatory registry conducted since its implantation and supervised by the regional health authorities. We included STEMI patients treated with PPCI from January 2010 to December 2020. We analyzed differences in clinical variables, reprefusion times and 1-year all-cause mortality regarding the FMC facility type.

Results

We included 18332 patients (EMS 34.25%, PCI-H 12.28%, CH 33.47%, PCC 20.01%). Initial Killip classes III–IV: EMS 8.43%, PCI-H 7.51%, CH 5.54%, PCC 3.76%; p<0.001. All comorbidities and complications in first medical assistance were more frequent in EMS and PCI-H groups (p<0.05). PCC group had the lowest risk profile regarding comorbidities and first medical assistance complications (p<0.05 for most of variables). The PCI-H group had the shortest system delay (median 82 min, p<0.001), the EMS group had the shortest total ischemic time (median 151 min, p<0.001). Crude 1-year mortality was EMS 8.6%, PCI-H 9.11%, CH 8.25%, and PCC 4.77% (p<0.001). After adjusting for several covariables with a logistic regression model, PCI-H and CH groups were associated with higher 1-year mortality compared to EMS group (OR 1.23 (IC95% 1.01–1.49; p=0.04) and OR 1.16 (IC95% 1.01–1.34; p=0.04) respectively), while PCC group was associated with lower 1-year mortality (OR 0.69 (IC95% 0.57–0.84; p<0.01)).

Conclusions

First medical contact with EMS and direct transfer to the cath lab was associated with lower adjusted 1-year mortality compared to first medical contact with a PCI hospital or a community hospital.

Funding Acknowledgement

Type of funding sources: None.

Clinical translation of [18F]ICMT-11 for measuring chemotherapy-induced caspase 3/7 activation in breast and lung cancer

BACKGROUND

Effective anticancer therapy is thought to involve induction of tumour cell death through apoptosis and/or necrosis. [18F]ICMT-11, an isatin sulfonamide caspase-3/7-specific radiotracer, has been developed for PET imaging and shown to have favourable dosimetry, safety, and biodistribution. We report the translation of [18F]ICMT-11 PET to measure chemotherapy-induced caspase-3/7 activation in breast and lung cancer patients receiving first-line therapy.

RESULTS

Breast tumour SUVmax of [18F]ICMT-11 was low at baseline and unchanged following therapy. Measurement of M30/M60 cytokeratin-18 cleavage products showed that therapy was predominantly not apoptosis in nature. While increases in caspase-3 staining on breast histology were seen, post-treatment caspase-3 positivity values were only approximately 1%; this low level of caspase-3 could have limited sensitive detection by [18F]ICMT-11-PET. Fourteen out of 15 breast cancer patients responded to first-line chemotherapy (complete or partial response); one patient had stable disease. Four patients showed increases in regions of high tumour [18F]ICMT-11 intensity on voxel-wise analysis of tumour data (classed as PADS); response was not exclusive to patients with this phenotype. In patients with lung cancer, multi-parametric [18F]ICMT-11 PET and MRI (diffusion-weighted- and dynamic contrast enhanced-MRI) showed that PET changes were concordant with cell death in the absence of significant perfusion changes.

CONCLUSION

This study highlights the potential use of [18F]ICMT-11 PET as a promising candidate for non-invasive imaging of caspase3/7 activation, and the difficulties encountered in assessing early-treatment responses. We summarize that tumour response could occur in the absence of predominant chemotherapy-induced caspase-3/7 activation measured non-invasively across entire tumour lesions in patients with breast and lung cancer.

Advanced capabilities for materials modelling with Quantum ESPRESSO

Quantum EXPRESSO is an integrated suite of open-source computer codes for quantum simulations of materials using state-of-the-art electronic-structure techniques, based on density-functional theory, density-functional perturbation theory, and many-body perturbation theory, within the plane-wave pseudopotential and projector-augmented-wave approaches. Quantum EXPRESSO owes its popularity to the wide variety of properties and processes it allows to simulate, to its performance on an increasingly broad array of hardware architectures, and to a community of researchers that rely on its capabilities as a core open-source development platform to implement their ideas. In this paper we describe recent extensions and improvements, covering new methodologies and property calculators, improved parallelization, code modularization, and extended interoperability both within the distribution and with external software.

Raman spectroscopy as probe of nanometre-scale strain variations in graphene

Confocal Raman spectroscopy has emerged as a major, versatile workhorse for the non-invasive characterization of graphene. Although it is successfully used to determine the number of layers, the quality of edges, and the effects of strain, doping and disorder, the nature of the experimentally observed broadening of the most prominent Raman 2D line has remained unclear. Here we show that the observed 2D line width contains valuable information on strain variations in graphene on length scales far below the laser spot size, that is, on the nanometre-scale. This finding is highly relevant as it has been shown recently that such nanometre-scaled strain variations limit the carrier mobility in high-quality graphene devices. Consequently, the 2D line width is a good and easily accessible quantity for classifying the crystalline quality, nanometre-scale flatness as well as local electronic properties of graphene, all important for future scientific and industrial applications.

Raman spectroscopy has become an invaluable tool for graphene characterisation, yet the nature of the broadening of the Raman 2D line remains unclear. Here, Stampfer et al. show that the Raman 2D line width is a measure of nanometre-scale strain variations in graphene on insulating substrates.

LARP1 post-transcriptionally regulates mTOR and contributes to cancer progression

RNA-binding proteins (RBPs) bind to and post-transcriptionally regulate the stability of mRNAs. La-related protein 1 (LARP1) is a conserved RBP that interacts with poly-A-binding protein and is known to regulate 5'-terminal oligopyrimidine tract (TOP) mRNA translation. Here, we show that LARP1 is complexed to 3000 mRNAs enriched for cancer pathways. A prominent member of the LARP1 interactome is mTOR whose mRNA transcript is stabilized by LARP1. At a functional level, we show that LARP1 promotes cell migration, invasion, anchorage-independent growth and in vivo tumorigenesis. Furthermore, we show that LARP1 expression is elevated in epithelial cancers such as cervical and non-small cell lung cancers, where its expression correlates with disease progression and adverse prognosis, respectively. We therefore conclude that, through the post-transcriptional regulation of genes such as mTOR within cancer pathways, LARP1 contributes to cancer progression.

Identification of Endoglin as an epigenetically regulated tumour-suppressor gene in lung cancer

Background:

The transforming growth factor-beta (TGF- β) pathway has been implicated in proliferation, migration and invasion of various cancers. Endoglin is a TGF-β accessory receptor that modulates signalling. We identified Endoglin as an epigenetically silenced tumour-suppressor gene in lung cancer by means of a genome-wide screening approach, then sought to characterise its effect on lung cancer progression.

Methods:

Methylation microarray and RNA sequencing were carried out on lung cancer cell lines. Epigenetic silencing of Endoglin was confirmed by methylation and expression analyses. An expression vector and a 20-gene expression panel were used to evaluate Endoglin function. Pyrosequencing was carried out on two independent cohorts comprising 112 and 202 NSCLC cases, respectively, and the impact of Endoglin methylation on overall survival (OS) was evaluated.

Results:

Methylation in the promoter region resulted in silencing of Endoglin, which could be reactivated by demethylation. Increased invasion coupled with altered EMT marker expression was observed in cell lines with an epithelial-like, but not those with a mesenchymal-like, profile when Endoglin was absent. Methylation was associated with decreased OS in stage I but not in stages II–III disease.

Conclusions:

We show that Endoglin is a common target of epigenetic silencing in lung cancer. We reveal a link between Endoglin silencing and EMT progression that might be associated with decreased survival in stage I disease.

Multidetector computed tomography (MDCT) for preoperative airway assessment in children with mucopolysaccharidoses

BACKGROUND

Accumulation of glycosaminoglycans is known to cause significant problems in the anesthetic management of children with mucopolysaccharidoses (MPS). Clinical and standard radiological evaluation may convey insufficient information about the upper airway and trachea in children with MPS. Multidetector computed tomography (MDCT) images have been used to define the central airway and previous studies have recommended this tool to assess the airway of children who are considered at risk of difficult intubation. However, MDCT has not been recommended in MPS children. The aim of this clinical scenario study was to verify whether information from MDCT reconstruction of the airway is useful in airway management planning of children with MPS.

METHODS

In a two phase questionnaire-based study, 26 pediatric anesthesiologists were asked to produce airway management plans for 5 children with MPS. An initial plan for airway control was reported after assessment of standard preoperative anesthetic charts. A subsequent airway strategy was then described after reviewing tracheal MDCT images of each patient.

RESULTS

MDCT images provided additional clinically-relevant information in 87% (95% CI: 79-92%) of the evaluations. Reduction of tracheal size was the most common finding provided by the MDCT images. After reviewing the MDCT images, anesthesiologists changed their primary airway device selection in 21% of the evaluations (P=0.01).

CONCLUSION

Airway reconstruction using MDCT images from a previous CT scan may provide a useful assessment tool for preoperative airway evaluation and planning in MPS children.

Thermal transport in isotopically disordered carbon nanotubes: a comparison between Green's functions and Boltzmann approaches

We present a study of the phononic thermal conductivity of isotopically disordered carbon nanotubes. In particular, the behaviour of the thermal conductivity as a function of the system length is investigated, using Green's function techniques to compute the transmission across the system. The method is implemented using linear scaling algorithms, which allow us to reach systems of lengths up to L = 2.5 µm (with up to 200 000 atoms). As for 1D systems, it is observed that the conductivity diverges with the system size L. We also observe a dramatic decrease of the thermal conductance for systems of experimental sizes (roughly 80% at room temperature for L = 2.5 µm), when a large fraction of isotopic disorder is introduced. The results obtained with Green's function techniques are compared to results obtained with a Boltzmann description of thermal transport. There is a good agreement between both approaches for systems of experimental sizes, even in the presence of Anderson localization. This is particularly interesting since the computation of the transmission using Boltzmann's equation is much less computationally expensive, so that larger systems may be studied with this method.

A new 2D-based method for myocardial velocity strain and strain rate quantification in a normal adult and paediatric population: assessment of reference values

BACKGROUND

Recent advances in technology have provided the opportunity for off-line analysis of digital video-clips of two-dimensional (2-D) echocardiographic images. Commercially available software that follows the motion of cardiac structures during cardiac cycle computes both regional and global velocity, strain, and strain rate (SR). The present study aims to evaluate the clinical applicability of the software based on the tracking algorithm feature (studied for cardiology purposes) and to derive the reference values for longitudinal and circumferential strain and SR of the left ventricle in a normal population of children and young adults.

METHODS

45 healthy volunteers (30 adults: 19 male, 11 female, mean age 37 +/- 6 years; 15 children: 8 male, 7 female, mean age 8 +/- 2 years) underwent transthoracic echocardiographic examination; 2D cine-loops recordings of apical 4-four 4-chamber (4C) and 2-chamber (2C) views and short axis views were stored for off-line analysis. Computer analyses were performed using specific software relying on the algorithm of optical flow analysis, specifically designed to track the endocardial border, installed on a Windows based computer workstation. Inter and intra-observer variability was assessed.

RESULTS

The feasibility of measurements obtained with tissue tracking system was higher in apical view (100% for systolic events; 64% for diastolic events) than in short axis view (70% for systolic events; 52% for diastolic events). Longitudinal systolic velocity decreased from base to apex in all subjects (5.22 +/- 1.01 vs. 1.20 +/- 0.88; p < 0.0001). Longitudinal strain and SR significantly increased from base to apex in all subjects (-12.95 +/- 6.79 vs. -14.87 +/- 6.78; p = 0.002; -0.72 +/- 0.39 vs. -0.94 +/- 0.48, p = 0.0001, respectively). Similarly, circumferential strain and SR increased from base to apex (-21.32 +/- 5.15 vs. -27.02 +/- 5.88, p = 0.002; -1.51 +/- 0.37 vs. -1.95 +/- 0.57, p = 0.003, respectively). Values of global systolic SR, both longitudinal and circumferential, were significantly higher in children than in adults (-1.3 +/- 0.2, vs. -1.11 +/- 0.2, p = 0.006; -1.9 +/- 0.6 vs. -1.6 +/- 0.5, p = 0.0265, respectively). No significant differences in longitudinal and circumferential systolic velocities were identified for any segment when comparing adults with children.

CONCLUSION

This 2D based tissue tracking system used for computation is reliable and applicable in adults and children particularly for systolic events. Measured with this technology, we have established reference values for myocardial velocity, Strain and SR for both young adults and children.

First principles NMR calculations of phenylphosphinic acid C6H5HPO(OH): assignments, orientation of tensors by local field experiments and effect of molecular motion

The complete set of NMR parameters for (17)O enriched phenylphosphinic acid C(6)H(5)HP( *)O(*OH) is calculated from first principles by using the Gauge Including Projected Augmented Wave (GIPAW) approach [C.J. Pickard, F. Mauri, All-electron magnetic response with pseudopotentials: NMR chemical shifts, Phys. Rev. B 63 (2001) 245101/1-245101/13]. The analysis goes beyond the successful assignment of the spectra for all nuclei ((1)H, (13)C, (17)O, (31)P), as: (i) the (1)H CSA (chemical shift anisotropy) tensors (magnitude and orientation) have been interpreted in terms of H bonding and internuclear distances. (ii) CSA/dipolar local field correlation experiments have allowed the orientation of the direct P-H bond direction in the (31)P CSA tensor to be determined. Experimental and calculated data were compared. (iii) The overestimation of the calculated (31)P CSA has been explained by local molecular reorientation and confirmed by low temperature static (1)H-->(31)P CP experiments.

Raman spectrum of graphene and graphene layers

Graphene is the two-dimensional building block for carbon allotropes of every other dimensionality. We show that its electronic structure is captured in its Raman spectrum that clearly evolves with the number of layers. The D peak second order changes in shape, width, and position for an increasing number of layers, reflecting the change in the electron bands via a double resonant Raman process. The G peak slightly down-shifts. This allows unambiguous, high-throughput, nondestructive identification of graphene layers, which is critically lacking in this emerging research area.

Pericardial tamponade as initial presentation of papillary thyroid carcinoma

We herein describe a 19-year-old woman who presented with pericardial effusion that resulted in heart tamponade. The clinicopathological study revealed papillary carcinoma of the thyroid metastasized to the heart. Although malignant pericardial effusion is a known complication of thyroid cancer, it is rarely the first manifestation and shows a relatively favourable prognosis despite widespread metastases if adequate treatment is given.

Atomic structure of icosahedral B4C boron carbide from a first principles analysis of NMR spectra

Density functional theory is demonstrated to reproduce the 13C and 11B NMR chemical shifts of icosahedral boron carbides with sufficient accuracy to extract previously unresolved structural information from experimental NMR spectra. B4C can be viewed as an arrangement of 3-atom linear chains and 12-atom icosahedra. According to our results, all the chains have a CBC structure. Most of the icosahedra have a B11C structure with the C atom placed in a polar site, and a few percent have a B (12) structure or a B10C2 structure with the two C atoms placed in two antipodal polar sites.

Differential expression of transforming growth factors-beta1, -beta2 and -beta3 in human colon carcinoma

Transforming growth factor (TGF)-beta is a protein family which affects multiple cellular functions including survival, proliferation, differentiation and adhesion. Among the three known isoforms, TGF-beta1 is commonly overexpressed in solid malignancies. Recent studies in knock-out mice demonstrated non-redundant roles of different TGF-beta isoforms in development. The present study was performed to assess tumour-associated expression of the three TGF-beta isoforms in colon carcinoma. We report that colon carcinoma progression is associated with gradual and significant increases in expression of TGF-beta1 and TGF-beta2 mRNA and proteins. By contrast, TGF-beta3 expression was detected in normal colonic mucosa and, at slightly higher levels, in tumour tissues. In addition, plasma levels of both TGF-beta1 and TGF-beta2 were significantly higher in cancer patients when compared with unaffected individuals. Taken together, our results indicate distinct expression patterns of the three TGF-beta isoforms in colon carcinoma cells and possible systemic effects of TGF-beta1 and TGF-beta2 in tumour patients.

Primary neuroendocrine carcinoma with ganglion cell differentiation in a crural lymph node

A primary neuroendocrine carcinoma with ganglion cell differentiation is described in a crural lymph node. The patient, a 48-year-old woman, presented a palpable lymph node of the crural region in March 1994. Histologically, the lesion was composed mostly of small cells immunoreactive for cytokeratins, neuron specific enolase and synaptophysin. The small cells merged gradually with areas containing ganglion cells immersed in a fibrillar matrix resembling neuropil. Ganglion cells expressed neuron-specific enolase, synaptophysin, neurofilament proteins and S-100 protein. Moreover, a minority of them featured cytokeratin expression. Electron microscopy was performed in the small cell component. These cells featured attenuated desmosomes and electron dense granules with an average size of 120 nm within bundles of intermediate filaments. Clinically, no tumour was found elsewhere despite extensive work-up over the 76-month follow-up period. Although similarities with previous cases of primary neuroendocrine carcinoma of lymph node, ganglion cell differentiation has never been described.

Efficacy of rescue thrombolysis in patients with acute myocardial infarction: preliminary findings

Thrombolysis reduces mortality in patients with acute myocardial infarction (AMI) who are hospitalized within 6 hours from the onset of symptoms. AMIs involving a small area of myocardium show a lower mortality in comparison with AMI involving a large area. The present study was aimed at evaluating the safety and efficacy of rescue thrombolysis in patients with large AMI who had failed thrombolysis. Ninety patients (69 Males and 21 Females), mean age 56.7 +/- 9 years, hospitalized for suspected AMI within 4 hours from the onset of symptoms, suitable for thrombolysis (First episode), and showing pain and persistent ST segment elevation 120 minutes after starting thrombolysis, were randomized (double-blind) into two groups. Group A (45 patients: 10 females and 35 males) received an additional thrombolytic treatment (rTPA 50 mg), 10 mg as bolus plus 40 mg in 60 minutes. Group B (45 patients: 11 females and 34 males) received placebo. Positive noninvasive markers were defined as follows: (1) resolution of chest pain, (2) > or = 50% reduction in ST segment elevation, (3) double marker of creatine kinase (CK) and CK-MB activity 2 hours after the start of thrombolysis, and (4) occurrence of reperfusion arrhythmias within the first 120 minutes of thrombolytic therapy. Blood pressure, heart rate, and ECG were continuously monitored. An echocardiogram was carried out at entry, and before discharge, to control ejection fraction and segmentary kinetics. Adverse events such as death, re-AMI, recurrent angina, incidence of major and minor bleeding, and emergency CABG/PTCA were checked. The groups were similar in terms of age, sex, diabetes, smoking habits, hypertension, and adjuvant therapy (beta-blockers). No significant difference was observed between the two groups regarding the time elapsed from the onset of symptoms to thrombolysis and AMI localization. Thirty-five patients (77.7%) showed reperfusion (10-50 minutes) after commencement of additional rTPA. Of the patients receiving placebo, 12 (26.6%) showed reperfusion within 35-85 minutes. Group A showed an earlier and lower CK and CK-MB peak than the control group, (respectively, p = 0.0001-0.009 and 0.002). Mortality (17.7%, 16 patients) was higher in group B than in the additional rTPA group, i.e., 6.6% (3 patients) in group A versus 28.8% (13 patients) in Group B (p = 0.041). Seven patients from group A showed nonfatal re-AMI. Angina was observed in 18 patients (40%) from group A and 3 (6.6%) from group B (p = 0.006). Ten of these patients underwent urgent PTCA (9 from group A and 1 from group B), and 3 from group A underwent urgent CABG. Minor bleeding was higher in group A than in group B (44.4% versus 15.5%, p = 0.047). Major bleeding was observed in group A (nonfatal stroke). At predischarge, the echocardiogram ejection fraction was higher in group A than in group B (46 +/- 8% versus 38 +/- 7%, p = 0.0001). Our data suggest that an additional dose of thrombolytic drug in patients with unsuccessful thrombolysis is feasible and also that the bleeding increase is an acceptable risk in comparison with the advantages obtained in reducing AMI extension. Rescue thrombolysis can allow a gain in time to perform mechanical revascularization in patients admitted to hospital without an interventionist cardiology laboratory or in those who have to be referred to another hospital for urgent CABG.

[The safety and efficacy of systemic salvage thrombolysis in acute myocardial infarct]

BACKGROUND

Thrombolysis reduces mortality in patients with acute myocardial infarction hospitalized within 6 hours of the symptom onset. Infarctions involving a small area of the myocardium show a lower mortality in comparison to those involving a large area. The aim of this study was to evaluate the safety and efficacy of rescue thrombolysis in patients with large acute myocardial infarction who had failed standard thrombolysis.

METHODS

From January 1995 to December 1997, ninety patients (69 males, 21 females, mean age 56.7 +/- 9 years), hospitalized for suspected acute myocardial infarction within 4 hours of the symptom onset, suitable for thrombolysis (first episode), and who experienced pain and showed persistent ST segment elevation 120 min after starting thrombolysis, were randomized (single blind) into two groups: Group A (n = 45) received an additional thrombolytic treatment (rt-PA 50 mg), 10 mg as a bolus plus 40 mg in 60 min; Group B (n = 45) received conventional therapy. Positive non-invasive markers were defined as follows: resolution of chest pain; > 50% reduction in ST segment elevation; double marker of creatine phosphokinase (CPK) and CK-MB activity 2 hours after the start of thrombolysis; occurrence of reperfusion arrhythmias within the first 120 min of thrombolytic therapy. Blood pressure, heart rate and ECG were continuously monitored. Echocardiogram was carried out at entry and before discharge to control ejection fraction and segmental wall motion. Adverse events such as death, reinfarction, recurrent angina, incidence of major and minor bleeding, and emergency bypass surgery or coronary angioplasty were checked.

RESULTS

Thirty-five patients (77.7%) showed reperfusion (10-50 min) after the start of additional rt-PA. In patients who did not receive additional thrombolysis, only 12 (26.6%) showed reperfusion 65-115 min after the end of rt-PA infusion. Group A showed an earlier and lower CK and CK-MB peak than Group B (p = 0.0001, p = 0.009, and p = 0.002, respectively). Mortality (n = 16, 17.7%) was higher in Group B (n = 13) than in Group A (n = 3) (28.8 vs 6.6%, p = 0.041). Seven patients from Group A showed non-fatal reinfarction. Angina was observed in 18 (40%) patients from Group A and 3 (6.6%) from Group B (p = 0.006). Ten of these patients underwent urgent coronary angioplasty (9 from Group A and 1 from Group B) and 3 from Group A urgent bypass surgery. Minor bleeding was higher in Group A than in Group B (44.4 vs 15.5%, p = 0.047). A major bleeding was observed in Group A (non-fatal stroke). At predischarge echocardiogram ejection fraction was higher in Group A than in Group B (46 +/- 8 vs 38 +/- 7%, p = 0.0001).

CONCLUSIONS

Our data suggest that an additional dose of a thrombolytic drug in patients with unsuccessful thrombolysis is feasible, and the bleeding increase is an acceptable risk in comparison with the advantages obtained from a reduced infarct extension. Rescue thrombolysis could save time and allow mechanical revascularization to be carried out in patients admitted to a hospital without interventional cardiology laboratory or in those who have to be refereed to other hospitals for urgent bypass surgery.

Intermittent 6-month low-dose dobutamine infusion in severe heart failure: DICE multicenter trial

BACKGROUND

Patients with end-stage heart failure are often refractory to maximal oral therapy, and they have high mortality rates, poor quality of life, and frequent hospitalizations with elevated health care costs. Intermittent dobutamine therapy has been suggested as an additional option in this clinical setting.

METHODS AND RESULTS

Thirty-eight patients clinically stable for at least 48 hours with standard treatment, New York Heart Association (NYHA) functional class III or IV, cardiac index </=2.2 L/min/m(2), and left ventricular ejection fraction </=30% were randomly assigned to ambulatory intermittent dobutamine or optimal standard treatment. Dobutamine was infused at 2.5 microgram/kg/min with a portable pump 48 hours/week for 6 months. The primary study end point was the reduction of hospitalizations for worsening of congestive heart failure (CHF); changes in NYHA functional class, 6-minute walking test, and mortality rates were secondary end points. During the 6-month follow-up, all patients in dobutamine and control groups underwent weekly clinical visits with serum sodium and potassium measurement. Baseline characteristics were age 65 +/- 2 years, NYHA class III/IV 17/21, ejection fraction 22% +/- 1%, and cardiac index 1.89 +/- 0.1 L/min/m(2), without differences between treatment groups. Hospitalizations for all causes over a 6-month period were 17 and 11 in control and dobutamine groups; 11 of 17 and 7 of 11 were for worsening CHF. Four control patients but none in the dobutamine group had 2 or more hospitalizations for worsening of CHF. There were no significant differences in NYHA functional class and in 6-minute walking test. Three patients in the control group died and 5 in the dobutamine group died. Two patients in the dobutamine group underwent heart transplantation. Protocol was discontinued in the dobutamine group for severe ventricular arrhythmias (1 patient), infusion system failure (1 patient), and consent withdrawal (1 patient). In 3 patients in the dobutamine group, drug dose was increased to 5 microgram/kg/min because of CHF.

CONCLUSIONS

Six-month intermittent low-dose dobutamine administration was well tolerated by patients with severe CHF; it did not improve the functional status and did not significantly increase the mortality rate as found with higher dobutamine doses in other studies. Hospitalizations for all causes and for worsening of CHF tended to be fewer in the dobutamine group.

Ten-year follow-up of the first megatrial testing thrombolytic therapy in patients with acute myocardial infarction: results of the Gruppo Italiano per lo Studio della Sopravvivenza nell'Infarto-1 study. The GISSI Investigators

BACKGROUND

We conducted a 10-year follow-up of the 11 712 patients with acute myocardial infarction randomized in the Gruppo Italiano per lo Studio della Sopravvivenza nell'Infarto-1 study, the first large trial assessing thrombolytic therapy.

METHODS AND RESULTS

Information on survival at 10 years was obtained for the 93% of all randomized patients through the census offices of their towns of residence. The difference in survival produced by streptokinase and sustained up to 1 year was still significant at 10 years (log-rank test, P=0.02), with the absolute benefit of 19 (95% CI 1 to 37) lives saved per 1000 patients treated. The time dependence of the extent of the benefit was confirmed, as the higher mortality rate reductions found in patients treated earlier were still present at 10 years. In the overall population, most of the benefit was obtained before hospital discharge (RR 0.81, 95% CI 0.72 to 0.90), since no difference in survival between thrombolyzed and control patients discharged alive was found at 10 years (RR 0.98, 95% CI 0.90 to 1.06). However, a slight albeit nonsignificant divergence of the survival curves of patients randomized within the first hour was observed [90 (95% CI 34 to 146) lives saved per 1000 at 10 years versus 72 (95% CI 37 to 107) lives saved at hospital discharge].

CONCLUSIONS

The benefits of a single intravenous infusion of 1.5 million units of streptokinase in prolonging survival of patients with acute myocardial infarction is sustained up to 10 years, with a still-evident trend in favor of the patients admitted earlier.

Determination of anandamide amidase activity using ultraviolet-active amine derivatives and reverse-phase high-performance liquid chromatography

Anandamide amidase catalyzes the hydrolysis of anandamide (AEA) to arachidonic acid (AA) and ethanolamine (EA). Recently, we published a method for determining anandamide amidase activity based on the measurement of arachidonic acid with direct UV detection at 204 nm. However, this method cannot be used to determine the hydrolysis of non-UV-active AEA analogs. It also cannot be used to study AEA amidase inhibitors that contain the arachidonic acid tail, and which are also enzyme substrates. Here we report a novel, more general method for measuring amidase activity by o-phthaldialdehyde (OPA) precolumn derivatization and reverse-phase high-performance liquid chromatography (HPLC). The hydrolysis product, ethanolamine, after separation from protein was derivatized with OPA to form a UV-active isoindole derivative which was then detected at 230 nm. The detection limit for derivatized ethanolamine was 1.0 pmol and retention times were typically less than 8 min. Our new method can detect non-UV-active analogs through derivatization of the amine product. It can thus be used after careful selection of the HPLC conditions in competition experiments between AEA and AEA analogs possessing different head groups. The most effective competitive inhibitor tested was (R)-N-(1-methyl-2-hydroxyethyl)arachidonylamide (AM356), which is resistant to enzymatic hydrolysis and yet inhibits AEA hydrolysis in a competition experiment by 43%. Moreover, this method offers several advantages over existing methodologies using radioisotopes or solvent extraction procedures. Our work to date has shown that small structural changes in the AEA molecule can result in significant variation in both affinity and turnover rate for each analog with respect to AEA amidase.

Identification and mass spectrometric sequence studies of fragments of l-asparaginase produced during freeze/thaw cycling

L-Asparaginase isolated from Er. chrysanthemi was found to lose activity upon exposure to consecutive freeze/thaw cycles. The cause(s) for this loss of activity were investigated using multiple techniques. SEC using UV, RI and light scattering detectors and SDS-PAGE indicated that the l-asparaginase molecule fragments upon exposure to repeated freezing and thawing cycles. Following up on this information, mass spectrometry was used to identify the fragments as small peptides of molecular weight 615 Da, 1424 Da and 1665 Da. Automated Edman sequencing of the frozen and thawed mixture confirmed the presence of fragments and contributed some sequence information. Mass spectral data and sequence studies of these fragments in conjunction with the known sequence of the molecule placed all the fragments within the last 28 C-terminal amino acids. A study of this region using the published 3 dimensional x-ray crystallographic structure of l-asparaginase revealed that the C-terminal region is exposed and can interact with water. The IBI MacVector program "Protein Tool Box" predicted that this region is hydrophilic, has a high surface probability and a strong tendency to interact with water. Both tendencies suggest a potential for bond stress during freeze/thaw cycling. This region is not involved at the catalytic core of the enzyme, but fragmentation in this area may result in unfolding and denaturation of the monomer followed by subsequent aggregation into large, insoluble entities and the loss of enzymatic activity.

Telepathology using Internet multimedia electronic mail: remote consultation on gastrointestinal pathology

The feasibility of using the Internet for remote pathology consultation was examined. We assessed the diagnostic agreement between two groups of pathologists who independently evaluated histopathological cases exchanged by Internet electronic mail. The exchange was between two different workstations using readily available software not specifically developed for telemedicine. Data and images from 76 cases were transmitted to four pathologists. An average of 4.5 images per case were transmitted at compression ratios of between 6:1 and 40:1, corresponding to 250 kByte of data per case. In two cases the remote pathologists could not make a diagnosis. Agreement was reached in 63 of the other 74 (kappa = 0.79). In 11 cases (15%) there was a misdiagnosis. However, the results are encouraging and suggest that Internet electronic mail can be used successfully for remote consultation in pathology.

Investigation of physicochemical changes to L-asparaginase during freeze-thaw cycling

L-Asparaginase derived from Erwinia chrysanthemi which is being investigated as an alternative to E. coli for the treatment of lymphoblastic leukaemia has been found in our laboratory to lose activity upon exposure to consecutive freeze-thaw cycles. An investigation was undertaken using several techniques to characterize fully the physicochemical changes L-Asparaginase is undergoing during freeze-thaw cycling leading to the loss of its activity. A total protein assay suggested that the loss of some enzyme activity was a result of protein precipitation. Circular dichroism (CD) studies showed a decrease of alpha-helical structure with a concomitant increase in beta sheet and random coil content, suggesting alterations in the secondary structure leading to unfolding, the first step of denaturation processes. The elution profiles obtained from size-exclusion chromatography (SEC) studies indicated the formation of several species during the process of freezing and thawing. Sodium dodecylsulphate-polyacrylamide gel electrophoresis (SDS-PAGE) studies showed bands corresponding to 1-3 kDa and 32 kDa, suggesting that some of the species are fragments and shortened monomers resulting from cleavage of monomers. The molecular weight distribution obtained using SEC-linked light scattering indicated a substantial fraction of polydispersed fragments ranging from 900 Da to 3 kDa and a small fraction of aggregates corresponding to 300 kDa. A scheme was proposed to explain the cascade of events leading to the loss of soluble protein and accompanying loss of enzyme activity. Tetramers of the enzyme dissociate into monomers some of which are cleaved into small fragments. The shortened monomers then aggregate and precipitate.

Expert pathology consultation through the Internet: melanoma versus benign melanocytic tumours

Twenty consecutive cases of melanocytic lesions were chosen from the archives of the archives of the institute of Anatomic Pathology at Santa Chiara Hospital, Trento. Representative images were acquired at a spatial resolution of 512 x 512 pixels, saved in IPEG format and delivered to the remote pathologist by multimedia internet electronic mail. Six cases were diagnosed as benign melanocytic lesions by the local pathologist. Of the 20 cases transmitted, each with an average of 5.3 images, the remote pathologist suggested a diagnosis of malignancy in nine cases while 10 cases were thought to be benign. In one case the images were not considered sufficient for diagnosis. Overall, the diagnostic agreement between local and remote pathologist was 79% (kappa = 0.58, P = 0.002). This preliminary study suggest that telepathology by internet electronic mail can be a valuable tool for remote consultation in dematopathology, as well as for other diagnostic fields where expert consultation is necessary.

Trends and determinants of calcium antagonist usage after acute myocardial infarction (the GISSI experience)

In the last decade, several clinical trials in patients with, or recovering from, acute myocardial infarction (AMI) have evaluated the role of calcium antagonists in affecting patients' prognosis. Results have been disparate, with evidence of possible harm, no effect, or some benefit, depending on the agent used. We evaluated how the evidence from these trials has influenced the pattern of prescription of calcium antagonists and assessed the important determinants of use of these agents in patients after AMI. We analyzed retrospectively the prescription of calcium antagonists at discharge in all patients recovering from AMI enrolled in 3 large randomized clinical trials (Gruppo Italiano per lo Studio della Sopravvivenza nell' Infarto-1 [GISSI-1], GISSI-2, and GISSI-3) during the last 10 years. A progressive decrease in prescriptions for calcium antagonists was evident, from 47.2% in GISSI-1 to 35.1% in GISSI-2 to 19.0% in GISSI-3 (p<0.001). The presence of post AMI angina, history of hypertension, and occurrence of reinfarction were associated with a higher usage of calcium antagonists, whereas the use of beta blockers at discharge was a major independent negative determinant. Use of calcium antagonists for secondary prevention after AMI (i.e., without specific clinical indications for their use) decreased by approximately 60% (from 26.1% to 10.3%). The data indicate that the usage of calcium antagonists in GISSI studies has been strongly affected by the results of other large multicenter trials evaluating calcium antagonists. These agents are now prescribed in patients after AMI almost exclusively in the presence of specific indications such as systemic hypertension or angina.

International guidelines and educational experiences in an out-patient clinic for asthma

In June 1989, an out-patient clinic for asthma was instituted at Crema Hospital, Italy. Up to November 1994, 430 adult asthmatics were recruited, classified and managed according to the recommendations of the international guidelines. The aims of this study are to verify: 1) whether the organization of the clinic could maintain asthma under control and reduce hospital admissions; and 2) whether the traditional educational approach could be implemented by lessons in the school of asthma to improve the control of asthma symptoms and/or admissions. The data reported refer to the first 360 asthmatics attending the clinic between 1989 and 1994: 53, 45 and 2% of them were suffering from extrinsic, intrinsic and occupational asthma, respectively. On recruitment, forced expiratory volume in one second (FEV1) was < 80% of predicted in 170 patients, and arterial oxygen tension (Pa,O2) 8.0 kPa (< 60 mmHg) in 27 patients. After the admission visit, 190 patients (53%) were classified as mild, 97 (27%) as moderate, and 73 (20%) as severe asthmatics. In May 1993, a school of asthma was organized. Forty four patients were recruited, stratified according to the severity of their asthma and randomized into two groups: 22 patients attended the school, and 22 patients did not. Each group consisted of 5, 10 and 7 patients with mild, moderate and severe asthma, respectively. The school comprised four lessons twice a week. One year after the end of the school, we could find no differences between the two groups (school versus controls) with regard to the number of urgent care visits (9 vs 9), scheduled visits (22 vs 21) and hospital admissions (2 vs 2).