688 In vivo expansion of gamma delta T cells by a CD19-targeted butyrophilin heterodimer leads to elimination of peripheral B cells

Background

A primary mechanism of cancer immunotherapy resistance involves downregulation of specific antigens or major histocompatibility complex based antigen presentation, which renders tumor cells invisible to alpha-beta T cells, but not gamma-delta T cells. Recently, a two-step model of gamma-delta T cell activation has emerged, wherein one butyrophilin (BTN, ie. BTN2A1) directly binds the gamma-delta TCR but is only activated if certain molecular patterns (eg. phosphoantigens) facilitate recruitment of a second BTN (ie. BTN3A1) into a complex to form a BTN2A1/3A1 heterodimer. The BTN2A1/3A1 complex specifically activates the predominant gamma-delta T cell population in the peripheral blood, comprising the Vg9d2 T cell receptor (TCR), but does not activate the primary gamma-delta T cell population in mucosal tissues, comprising the Vg4 TCR. The unique mechanism of action and specificity of gamma-delta TCR/BTN interactions suggests that therapeutic proteins comprising specific BTN heterodimers could be used to target specific gamma-delta T cell populations, with a lower risk of off-target activation common with CD3-directed T cell engagers.

Methods

Human BTN2A1/3A1-Fc-CD19scFv and mouse BTNL1/6-Fc-CD19scFv heterodimeric fusion proteins were purified and binding to CD19 or the respective gamma-delta TCRs was assessed by ELISA, Octet and flow cytometry using gd T-cells isolated from human peripheral blood and mouse intestinal tissue. The functionality of the constructs to activate gamma-delta T cells and mediate killing of tumor cells was assessed using live cell imaging in vitro as well as a murine B-cell lymphoma model in vivo.

Results

The CD19-targeting scFv domains of the BTN heterodimer fusion proteins bound to human and mouse CD19 with low nanomolar affinity. The BTN2A1/3A1-Fc-CD19scFv compound specifically bound to the Vg9d2 TCR on human gd T cells while the mouse BTNL1/6-Fc-CD19scFv bound to Vg7d4 TCR on mouse gd T cells. Both compounds were able to activate gd T cells in a co-culture assay resulting in degranulation and increased surface expression of CD107a and also increased apoptosis of CD19+ tumor cells. Intraperitoneal administration of the mouse BTNL1/6-Fc-CD19scFv led to anti-tumor effects in A20 tumor bearing BALB/c mice. Phenotyping from BTNL1/6-Fc-CD19scFv treated mice revealed profound and rapid expansion of the endogenous gamma-delta T cells in the circulation and tumor, with concomitant depletion of peripheral CD19+ B-cells, confirming the mechanism of action of the heterodimer as a gamma-delta T cell specific engager.

Conclusions

These results provide proof of mechanism for in vivo manipulation of gamma-delta T cells using antigen-targeted butyrophilin heterodimeric fusion proteins for the treatment of cancer.

Assessing the performance of artificial reefs as substitute habitat for temperate reef fishes: Implications for reef design and placement

Artificial reefs (ARs) have been advocated and implemented as management tools for recreational fisheries, species conservation and habitat replacement. For ARs to function as substitute habitat for degraded natural reefs, they should perform as close as possible to local natural reefs, however this is seldom investigated. Here we evaluated the performance of new custom-designed reef structures (CDARs) as fish habitat. As a benchmark for their success, we compared fish abundance, diversity and community composition on CDARs to another commonly used AR type (Reef Balls (RBs)) and nearby natural reefs. Fish were monitored on all reef types over two recruitment seasons at three locations in Port Phillip Bay, Australia. Overall, there were no consistent differences in fish density among reef types, although densities on both AR designs were markedly lower than natural reefs at some locations. However, fish species richness on the CDARs was, on average, 2× higher than natural or RB reefs. There were large dissimilarities in fish community composition among reef types across all locations and years. These dissimilarities declined over time with the CDARs becoming more similar to natural communities than to RB reefs. Our results suggest that CDARs can play a role in reef fish conservation where natural reefs are under threat, supporting natural community structure and enhancing local biodiversity. Overall, our findings suggest that location of deployment, rather than design, has a more significant influence on fish abundances on ARs, whereas reef design is an important determinant of species diversity and community structure irrespective of location. ARs represent an important management tool for enhancing fisheries productivity and conservation in areas where reef habitat has been degraded or lost. However, failure to incorporate consideration of reef location and design into future AR deployments may lead to poor performance and failure to achieve restoration or conservation goals.

Diabetes and hypercholesterolemia increase blood-brain barrier permeability and brain amyloid deposition: beneficial effects of the LpPLA2 inhibitor darapladib

Diabetes mellitus (DM) and hypercholesterolemia (HC) have emerged as major risk factors for Alzheimer's disease, highlighting the importance of vascular health to normal brain functioning. Our previous study showed that DM and HC favor the development of advanced coronary atherosclerosis in a porcine model, and that treatment with darapladib, an inhibitor of lipoprotein-associated phospholipase A2, blocks atherosclerosis progression and improves animal alertness and activity levels. In the present study, we examined the effects of DM and HC on the permeability of the blood-brain barrier (BBB) using immunoglobulin G (IgG) as a biomarker. DMHC increased BBB permeability and the leak of microvascular IgG into the brain interstitium, which was bound preferentially to pyramidal neurons in the cerebral cortex. We also examined the effects of DMHC on the brain deposition of amyloid peptide (Aβ42), a well-known pathological feature of Alzheimer's disease. Nearly all detectable Aβ42 was contained within cortical pyramidal neurons and DMHC increased the density of Aβ42-loaded neurons. Treatment of DMHC animals with darapladib reduced the amount of IgG-immunopositive material that leaked into the brain as well as the density of Aβ42-containing neurons. Overall, these results suggest that a prolonged state of DMHC may have chronic deleterious effects on the functional integrity of the BBB and that, in this DMHC pig model, darapladib reduces BBB permeability. Also, the preferential binding of IgG and coincident accumulation of Aβ42 in the same neurons suggests a mechanistic link between the leak of IgG through the BBB and intraneuronal deposition of Aβ42 in the brain.

Outcomes associated with a thrice-weekly antimicrobial stewardship programme in a 253-bed community hospital

WHAT IS KNOWN AND OBJECTIVES

Antimicrobial stewardship programmes (ASPs) have been shown to decrease antimicrobial resistance, reduce hospital-acquired infections and decrease overall antimicrobial expenditures. At St. Joseph Medical Center in Bellingham, WA, a thrice-weekly ASP was initiated in 2010 with the goals of decreasing carbapenem, fluoroquinolone and vancomycin use and tailoring duration of therapy.

METHODS

Antibiotic use per 1000 patient-days and carbapenem, fluoroquinolone and vancomycin use were evaluated pre- and post-implementation of the ASP. Total antimicrobial expenditures were evaluated for the 3 years prior to ASP implementation and three years following implementation.

RESULTS AND DISCUSSION

Antimicrobial days of therapy per 1000 patient-days declined by 6·4% after implementation of our ASP. There was a 37% reduction in total antimicrobial expenditures after implementation. Carbapenems, vancomycin and levofloxacin use decreased considerably. Ciprofloxacin use increased during the same time period.

WHAT IS NEW AND CONCLUSION

A thrice-weekly, pharmacist-driven ASP can decrease antimicrobial expenditure, shorten duration of therapy and decrease the utilization of carbapenems, vancomycin and levofloxacin.

Bibliotherapy and information prescriptions: a summary of the published evidence-base and recommendations from past and ongoing Books on Prescription projects

This paper summarizes the published evidence and reports from ongoing and completed projects that used Bibliotherapy and Information Prescription to deliver patient care. A literature search was conducted and relevant papers were summarized into: type of study, type of Bibliotherapy, client group and recommendations. In total, 65 papers were considered with 57 reviewed. A survey was also sent to Library Authorities subscribing to national survey standards asking for details about delivery of Information Prescription projects. There were 21 returned surveys. The experiences and recommendations were then summarized. The aim of the paper is to collate the evidence-base of written research and the experience and recommendations of projects into an easy format so that practitioners interested in using Bibliotherapy/Information Prescription/Books on Prescription have an understanding what they are, the extent of the evidence-base to inform practice, and highlight gaps in the research.

Intrinsic stability and functional properties of disulfide bond-stabilized coagulation factor VIIIa variants

BACKGROUND

The utility of purified coagulation factor (F)VIII for treatment of hemophilia A is limited in part by its instability following activation by thrombin, which is caused by spontaneous dissociation of the A2 domain from the activated FVIII (FVIIIa) heterotrimer. To prevent this A2 domain dissociation in FVIIIa, we previously engineered a cysteine pair (C664-C1826) in recombinant FVIII that formed a disulfide bond cross-linking the A2 domain in the heavy chain to the A3 domain in the light chain. This engineered disulfide bond resulted in a more stable FVIIIa.

AIMS

Here, we characterize the functional parameters of C664-C1828 FVIII and of a new disulfide bond-stabilized FVIII (C662-C1828 FVIII).

METHODS

In order to assess whether these FVIII variants might be good candidates for a new therapeutic agent to treat hemophilia A, we investigated a variety of functional parameters that might affect the in vivo properties of the variants, including half-life of disulfide bond-stabilized FVIII and FVIIIa and the potency of these FVIIIa molecules in the FXase complex.

RESULTS

Both disulfide bond-stabilized variants had improved affinity for von Willebrand factor (VWF). In studies of FX activation by purified FIXa and FVIIIa, C662-C1828 FVIIIa had normal activity while C664-C1826 FVIIIa had reduced activity. Both C664-C1826 FVIIIa and C662-C1828 FVIIIa were inactivated by activated protein C (APC) but the rates of inactivation were different.

CONCLUSION

Overall, the specific location of the disulfide bridge between the A2 and A3 domains appears to affect functional properties of FVIIIa. In summary, introduction of engineered interdomain disulfides results in FVIIIa variants that resist spontaneous loss of activity while retaining susceptibility to APC proteolytic inactivation and maintaining VWF binding.

International multicentre trial protocol to assess the efficacy and safety of tenecteplase during cardiopulmonary resuscitation in patients with out-of-hospital cardiac arrest: the Thrombolysis in Cardiac Arrest (TROICA) Study

Prehospital cardiac arrest has been associated with a very poor prognosis. Acute myocardial infarction and massive pulmonary embolism are the underlying causes of out-of-hospital cardiac arrest in 50-70% of patients. Although fibrinolysis is an effective treatment strategy for both myocardial infarction and pulmonary embolism, clinical experience for this therapy performed during resuscitation has been limited owing to the anticipated risk of severe bleeding complications. The TROICA study is planned as one of the largest randomized, double-blind, placebo-controlled trials to assess the efficacy and safety of prehospital thrombolytic therapy in cardiac arrest of presumed cardiac origin. Approximately 1000 patients with cardiac arrest will be randomized at approximately 60 international study centres to receive either a weight-adjusted dose of tenecteplase or placebo after the first dose of a vasopressor. Patients can be included if they are at least 18 years, presenting with a witnessed cardiac arrest of presumed cardiac origin, and if either basic life support had started within 10 min of onset and had been performed up to 10 min or advanced life support is started within 10 min of onset of cardiac arrest. Primary endpoint of the study is the 30-day survival rate, and the coprimary endpoint is hospital admission. Secondary endpoints are the return of spontaneous circulation (ROSC), survival after 24 h, survival to hospital discharge, and neurological performance. Safety endpoints include major bleeding complications and symptomatic intracranial haemorrhage.

Primary pleural epithelioid haemangioendothelioma with metastases to the skin. A case report and literature review

Epithelioid haemangioendothelioma (EHE) is a rare vascular tumour of intermediate behaviour. It can arise from various sites including the liver, spleen, pleura, or lung. Cutaneous EHE can be primary or secondary. This report describes the case of a 51 year old man who presented with a history of dry cough, shortness of breath, and pleural effusion, and who developed two cutaneous nodules in the anterior abdominal wall a few weeks later. He had a previous history of asbestos exposure. Computed tomography scan showed a left sided pleural effusion and nodular pleural mass. Histology of both the pleural and cutaneous lesions was compatible with EHE. Electron microscopic examination demonstrated the presence of Weibel-Palade bodies. The patient underwent elliptical excision of the metastatic cutaneous nodules after decortication of the primary pleural tumour and adjuvant treatment. A few reports have described metastasis of intrathoracic EHE to the skin. Despite treatment with interferon, the patient developed more cutaneous lesions two years after the initial diagnosis. Even though the tumour has the classic light histological and ultrastructural features of EHE, it behaved in an aggressive manner.

Rapidly progressive pulmonary fibrosis in a patient treated with danazol for idiopathic thrombocytopenic purpura

The case of a patient that developed pulmonary fibrosis two months after initiation of danazol for treatment of idiopathic thrombocytopenic purpura is described. Bilateral pneumothoraxes and pneumomediastinum complicated the rapidly fatal pulmonary fibrosis. An association between danazol therapy and the development of pulmonary fibrosis is suspected. There is only one other case report with this connection in the literature.

Bilateral lung transplantation for metastatic leiomyosarcoma

As increased experience is gained in the field of lung transplantation, novel applications for this life saving therapy will evolve. We have described a case of bilateral lung transplantation in a young patient with respiratory failure secondary to metastatic leiomyosarcoma that was limited to the lungs. While lung transplantation for malignancy remains a controversial area, this case illustrates that lung transplantation can provide improved quality and quantity of life for highly selected patients with malignant disease.

De novo pulmonary capillary hemangiomatosis occurring rapidly after bilateral lung transplantation

A 45-year-old woman experienced diffuse bilateral pulmonary capillary hemangiomatosis within 3 months after bilateral lung transplantation. The donor was a 41-year-old man with excellent lung function and without histologic or macroscopic pulmonary lesions at the time of retrieval. This case supports the theory that persistent infection or inflammation may be an inciting factor in uncontrolled angiogenesis, leading ultimately to diffuse pulmonary capillary hemangiomatosis.

Phosphoinositide 3-kinase regulates beta2-adrenergic receptor endocytosis by AP-2 recruitment to the receptor/beta-arrestin complex

Internalization of beta-adrenergic receptors (betaARs) occurs by the sequential binding of beta-arrestin, the clathrin adaptor AP-2, and clathrin. D-3 phosphoinositides, generated by the action of phosphoinositide 3-kinase (PI3K) may regulate the endocytic process; however, the precise molecular mechanism is unknown. Here we demonstrate that betaARKinase1 directly interacts with the PIK domain of PI3K to form a cytosolic complex. Overexpression of the PIK domain displaces endogenous PI3K from betaARK1 and prevents betaARK1-mediated translocation of PI3K to activated beta2ARs. Furthermore, disruption of the betaARK1/PI3K interaction inhibits agonist-stimulated AP-2 adaptor protein recruitment to the beta2AR and receptor endocytosis without affecting the internalization of other clathrin dependent processes such as internalization of the transferrin receptor. In contrast, AP-2 recruitment is enhanced in the presence of D-3 phospholipids, and receptor internalization is blocked in presence of the specific phosphatidylinositol-3,4,5-trisphosphate lipid phosphatase PTEN. These findings provide a molecular mechanism for the agonist-dependent recruitment of PI3K to betaARs, and support a role for the localized generation of D-3 phosphoinositides in regulating the recruitment of the receptor/cargo to clathrin-coated pits.

Coronary angioplasty versus medical therapy for angina. Health service costs based on the second Randomized Intervention Treatment of Angina (RITA-2) trial

AIMS

The second Randomized Intervention Treatment of Angina (RITA-2) trial compares an initial strategy of PTCA with continued medical management in patients with arteriographically proven coronary artery disease. This paper employs resource use data collected in the trial to compare the health service costs of the two strategies over 3 years follow-up.

METHODS AND RESULTS

1018 patients were randomized, 504 to PTCA and 514 to continued medical management. Health service resource use data were collected prospectively on all patients. Hospital unit costs were estimated in collaboration with five U.K. centres. PTCA patients underwent more subsequent coronary arteriograms, but subsequent (non-randomized) PTCAs were more common in patients randomized to medical management (118 procedures in 102 patients) compared to those randomized to PTCA (73 procedures in 62 patients). The likelihood of undergoing CABG was similar in the two groups. The use of antianginal medications was higher in patients randomized to an initial strategy of medical management. There was an overall mean additional cost per patient over 3 years in patients randomized to PTCA of pound 2685 (95% CI pound 2074- pound 3322).

CONCLUSIONS

In RITA-2, the cost of an initial strategy of PTCA exceeded the cost of an initial strategy of medical management by 74% over 3 years.

The speech-language pathologist's role in a writing lab approach

In a writing lab approach, speech-language pathologists (SLPs) work on collaborative teams with general and special educators to foster language growth using inclusive, curriculum-based, computer-supported writing process instruction. By engaging students in authentic writing projects using recursive writing processes--planning, organizing, drafting, revising, editing, publishing, presenting--and supporting them with instructional scaffolding, peer feedback, and computers, SLPs can address individualized needs while achieving goals of the general education curriculum. Case examples illustrate how intervention can be designed to meet the needs of students with diverse disabilities to interact socially and progress academically within the general education curriculum.

Randomised controlled trials of staged teaching for basic life support: 2. Comparison of CPR performance and skill retention using either staged instruction or conventional training

Teaching CPR in stages is a strategy designed to improve skill acquisition and retention. This method has been compared with conventional teaching in a randomised trial involving 495 volunteers. The first ('bronze') stage was simplified by omitting ventilation and giving compressions in sets of 50 with pauses to open the victim's airway; in the second ('silver') stage ventilation was introduced in a ratio of 50 compressions to five breaths, and in the third ('gold') stage, the volunteers were converted to conventional CPR. 51% of those taught by this method reattended for the second ('silver') stage compared with 25% who were taught conventional CPR and advised to return for a revision session. 38% of the staged group reattended for the third ('gold') compared with 8% for the conventional group. Modest improvement in skill acquisition has earlier been reported for the 'bronze' stage teaching, and this has been followed by better performance in some of the components tested after the subsequent stages. Comparisons after the 'gold' stage were limited by the small numbers who reattended for a third session of conventional training, but no special difficulties were noted in changing the ratio of compressions to ventilation that was necessary to convert the staged training volunteers to conventional CPR. The increased number of compressions that can be achieved by teaching 'bronze' stage CPR with no ventilation was retained, to a lesser degree, when the 'silver' ratio of 50 compressions to five breaths was compared with the conventional 15:2 ratio. Our observations suggest that during the first critical 8 min of a resuscitation attempt, 58% more compressions might be delivered by using the 50:5 ratio - an increase that is likely to result in a significant augmentation of blood flow with important clinical implications. More comparative information will become available when the results of unannounced home testing are analysed.

Improved functional recovery of denervated skeletal muscle after temporary sensory nerve innervation

Prolonged muscle denervation results in poor functional recovery after nerve repair. The possible protective effect of temporary sensory innervation of denervated muscle, prior to motor nerve repair, has been examined in the rat. Soleus and gastrocnemius muscles were denervated by cutting the tibial nerve, and the peroneal nerve was then sutured to the transected distal tibial nerve stump either immediately or after two, four or six months. In half of the animals with delayed repair, the saphenous (sensory) nerve was temporarily attached to the distal nerve stump. Muscles were evaluated three months after the peroneal-to-tibial union, and were compared with each other, with unoperated control muscles and with untreated denervated muscles. After four to six months of sensory "protection", gastrocnemius muscles weighed significantly more than unprotected muscles, and both gastrocnemius and soleus muscles exhibited better preservation of their structure, with less fiber atrophy and connective tissue hyperplasia. The maximum compound action potentials were significantly larger in gastrocnemius and soleus muscles following sensory protection, irrespective of the delay in motor nerve union. Isometric force, although less than in control animals and in those with immediate nerve repair, remained reasonably constant after sensory protection, while in unprotected muscles there was a progressive and significant decline as the period of denervation lengthened. We interpret these results as showing that, although incapable of forming excitable neuromuscular junctions, sensory nerves can nevertheless exert powerful trophic effects on denervated muscle fibers. We propose that these findings indicate a useful strategy for improving the outcome of peripheral nerve surgery.

Optimal Response to Cardiac Arrest study: defibrillation waveform effects

INTRODUCTION

Advances in early defibrillation access, key to the "Chain of Survival", will depend on innovations in defibrillation waveforms, because of their impact on device size and weight. This study compared standard monophasic waveform automatic external defibrillators (AEDs) to an innovative biphasic waveform AED.

MATERIAL AND METHODS

Impedance-compensated biphasic truncated exponential (ICBTE) and either monophasic truncated exponential (MTE) or monophasic damped sine (MDS) AEDs were prospectively, randomly assigned by date in four emergency medical services. The study design compared ICBTE with MTE and MDS combined. This subset analysis distinguishes between the two classes of monophasic waveform, MTE and MDS, and compares their performance to each other and to the biphasic waveform, contingent on significant overall effects (ICBTE vs. MTE vs. MDS). Primary endpoint: Defibrillation efficacy with < or =3 shocks. Secondary endpoints: shock efficacy with < or =1 shock, < or =2 shocks, and survival to hospital admission and discharge. Observations included return of spontaneous circulation (ROSC), refibrillation, and time to first shock and to first successful shock.

RESULTS

Of 338 out-of-hospital cardiac arrests, 115 had a cardiac aetiology, presented with ventricular fibrillation, and were shocked by an AED. Defibrillation efficacy for the first "stack" of up to 3 shocks, for up to 2 shocks and for the first shock alone was superior for the ICBTE waveform than for either the MTE or the MDS waveform, while there was no difference between the efficacy of MTE and MDS. Time from the beginning of analysis by the AED to the first shock and to the first successful shock was also superior for the ICBTE devices compared to either the MTE or the MDS devices, while again there was no difference between the MTE and MDS devices. More ICBTE patients achieved ROSC pre-hospital than did MTE patients. While the rates of ROSC were identical for MTE and MDS patients, the difference between ICBTE and MDS was not significant. Rates of refibrillation and survival to hospital admission and discharge did not differ among the three populations.

CONCLUSIONS

ICBTE was superior to MTE and MDS in defibrillation efficacy and speed and to MTE in ROSC. MTE and MDS did not differ in efficacy. There were no differences among the waveforms in refibrillation or survival.

Anaphylaxis management in primary care

The United Kingdom Resuscitation Council Project Team has issued revised guidelines on the emergency treatment of anaphylactic reactions in the community setting in response to community nurses' concerns. A consensus has now been reached.

European Resuscitation Council Guidelines 2000 for Adult Advanced Life Support. A statement from the Advanced Life Support Working Group(1) and approved by the Executive Committee of the European Resuscitation Council

The European Resuscitation Council (ERC) last issued guidelines for Basic Life Support (BLS) in 1998 [1]. These were based on the 1997 International Liaison Committee on Resuscitation (ILCOR) Advisory Statements [2]. In 1999 and 2000 representatives of ILCOR, at the invitation of the American Heart Association, met on a number of occasions in Dallas to agree a Consensus on Science upon which future guidelines would be based. Representatives from the ERC played a prominent role in the deliberations, which culminated in the publication of "Guidelines 2000 for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care--A Consensus on Science" in August 2000 [3]. The consensus was evidence-based wherever possible. The ERC ALS Working Group has considered this document and has recommended some changes in the guidelines that will be suitable for European practice. These changes, together with a summary of the Sequence of Actions in ALS, are presented in this paper.

Multicenter, randomized, controlled trial of 150-J biphasic shocks compared with 200- to 360-J monophasic shocks in the resuscitation of out-of-hospital cardiac arrest victims. Optimized Response to Cardiac Arrest (ORCA) Investigators

BACKGROUND

In the present study, we compared an automatic external defibrillator (AED) that delivers 150-J biphasic shocks with traditional high-energy (200- to 360-J) monophasic AEDs.

METHODS AND RESULTS

AEDs were prospectively randomized according to defibrillation waveform on a daily basis in 4 emergency medical services systems. Defibrillation efficacy, survival to hospital admission and discharge, return of spontaneous circulation, and neurological status at discharge (cerebral performance category) were compared. Of 338 patients with out-of-hospital cardiac arrest, 115 had a cardiac etiology, presented with ventricular fibrillation, and were shocked with an AED. The time from the emergency call to the first shock was 8.9+/-3.0 (mean+/-SD) minutes.

CONCLUSIONS

The 150-J biphasic waveform defibrillated at higher rates, resulting in more patients who achieved a return of spontaneous circulation. Although survival rates to hospital admission and discharge did not differ, discharged patients who had been resuscitated with biphasic shocks were more likely to have good cerebral performance.

Difficult asthma: consider all of the possibilities

Asthma is a common respiratory disease that can often be managed successfully. However, there are patients that do not respond to the maximum doses of standard therapy and subsequently have a reduced quality of life. Many factors can contribute to a failure to respond to treatment, and a comprehensive approach is important when assessing and evaluating these patients. This report describes a patient referred for 'difficult to control asthma' who had multiple emergency department visits and hospitalizations. In addition to a history of wheezing, spirometry showed impaired flow and vital capacity was reduced. Further investigation showed a normal total lung capacity, and a computed tomography scan revealed main bronchus blockage by a tumour, which was confirmed by bronchoscopy. This led to a surgical resection of a mucoepidermoid carcinoma. This case highlights the need to consider all possibilities during the evaluation of patients with difficult asthma.

Hearing conservation for farmers: source apportionment of occupational and environmental factors contributing to hearing loss

Those who work on farms continue to have a strikingly high prevalence of hearing loss, despite efforts to promote hearing conservation in agriculture. To develop improved hearing conservation programs, we performed a source apportionment analysis for hearing loss in a large, multiphasic health survey, the New York Farm Family Health and Hazard Survey. We used information from audiometric, otoscopic, and tympanometric examinations; detailed general health and farm exposure interviews; and a second interview that focused on additional potential determinants of hearing loss. Hearing loss on audiometry was significantly associated with increased age, male gender, education through high school or less, lifetime years of hunting with guns, lifetime years of use of a grain dryer, and a history of spraying crops during the previous year. Hearing conservation programs for farmers should thus be directed toward reduction in noise exposure, both from occupational and non-occupational sources. Additional study is needed to evaluate the association seen between crop spraying and hearing loss.

Randomised controlled trials of staged teaching for basic life support. 1. Skill acquisition at bronze stage

We have investigated a method of teaching community CPR in three stages instead of in a single session. These have been designated bronze, silver, and gold stages. The first involves only opening of the airway and chest compression with back blows for choking, the second adds ventilation in a ratio of compressions to breaths of 50:5, and the third is a conversion to conventional CPR. In a controlled randomised trial of 495 trainees we compared the performance in tests immediately after instruction of those who had received a conventional course and those who had had the simpler bronze level tuition. The tests were based on video recordings of simulated resuscitation scenarios and the readouts from recording manikins. Differences occurred as a direct consequence of ventilation being required in one group and not the other, some variation probably followed from unforeseen minor changes in the way that instruction was given, whilst others may have followed from the greater simplicity in the new method of training. A careful approach was followed by slightly more trainees in the conventional group whilst appreciably more in the bronze group remembered to shout for help (44% vs. 71%). A clear advantage was also seen for bronze level training in terms of those who opened the airway as taught (35% vs. 56%), for checking breathing (66% vs. 88%), and for mentioning the need to phone for an ambulance (21% vs. 32%). Little difference was observed in correct or acceptable hand position between the conventional group who were given detailed guidance and the bronze group who were instructed only to push on the centre of the chest. The biggest differences related to the number of compressions given. The mean delay to first compression was 63 s and 34 s, and the mean duration of pauses between compressions was 16 s and 9 s, respectively. Average performed rates were similar in the two groups, but more in the conventional group compressed too slowly whereas more in the bronze group compressed too rapidly. Observations were made for only three cycles of compression, but extrapolating these to the 8 min often considered a watershed for chances of survival for victims of cardiac arrest, an average of 308 compressions would be expected from those using conventional CPR compared with 675 for those using bronze level CPR. The implications of this difference are discussed.

Correlation of chest radiographic findings with biopsy-proven acute lung rejection

The purpose of this study was to determine the chest radiographic findings of acute rejection and the accuracy of chest radiography in making this diagnosis in patients undergoing lung transplantation. For each of 100 transbronchial biopsies performed on 25 lung transplant recipients (single lung in three, double lung in 22), chest radiographs obtained within 24 hours before the biopsy were reviewed retrospectively without knowledge of clinical or biopsy information. Transbronchial biopsy revealed 42 instances of acute rejection in 17 patients and 58 instances of no acute rejection (normal, n = 43; other processes, n = 15). All pulmonary parenchymal radiographic abnormalities were assessed. Acute rejection was associated with the presence of middle or lower lung reticular interstitial or airspace disease in 21 lungs (sensitivity = 0.50 [21/42]). This pattern was seen in 18 lungs without acute rejection (specificity = 0.69 [40/58]). There was no difference in the appearance of the lungs between grades 1 and 2 acute rejection. Normal lungs were noted in 20 instances of acute rejection (48%). The authors conclude that chest radiograph findings are abnormal in about 50% of instances of biopsy-proven acute rejection. Because the appearance of acute rejection is similar to that of other conditions, the diagnosis cannot be made accurately by chest radiography.

Upregulation of T-helper 1 cytokines and chemokine expression in post-transplant airway obliteration

The major obstacle to long-term survival after lung transplantation is chronic graft dysfunction manifest as bronchiolitis obliterans. Since the early stages are characterized by proliferation of itinerant cells (lymphocytes and macrophages), we hypothesized that cytokines and chemokines may play a role in the development of the fibroproliferative process. In a heterotopic rat tracheal transplant model, we studied isografts and allografts 3, 7, and 21 d after transplantation as representative time points for the triphasic time course in the evolution of allograft airway obliteration. Using a semiquantitative RT-PCR technique, intragraft gene expression of T-helper 1 (Th1)- and Th2-type cytokines and of C-C and C-X-C chemokines was examined. The results of our study show a distinct pattern of cytokine and chemokine gene expression in the development of post-transplant airway obliteration. Allografts, in contrast to isografts, showed a strong and persistent Th1-type response (expression of interleukin-2 and interferon-gamma genes), even after fibrous airway obliteration was complete, suggesting an ongoing allo-immune process until late in the fibroproliferative stage. RANTES and MCP-1 were also upregulated late after transplantation, whereas MIP-2 upregulation occurred early post-transplant and was not restricted to allografts alone, which might reflect alloantigen-independent processes after transplantation that are present in both allografts and isografts.

Expression and prognostic significance of metalloproteinases and their tissue inhibitors in patients with small-cell lung cancer

PURPOSE

Matrix metalloproteinases (MMPs) and their tissue inhibitors (TIMPs) are important in tumor development and progression. MMP expression has been correlated with advanced clinical stage and poor survival in some tumors, but data for small-cell lung cancer (SCLC) are lacking. The aim of this study was to assess the expression of MMPs and TIMPs in SCLC and to evaluate their importance relative to standard prognostic factors.

PATIENTS AND METHODS

Expression of MMP-1, -2, -3, -9, -11, -13, and -14 and TIMP-1, -2, -3, and -4 was evaluated by immunohistochemistry (IHC). In situ hybridization was used to confirm expression of specific mRNAs. Clinical data collected included sex, tumor stage, performance status, weight loss, hematology (hemoglobin, WBC, platelets) and biochemistry (sodium, albumin, alkaline phosphatase, lactate dehydrogenase), treatment, and survival.

RESULTS

Samples from 46 patients were evaluated: 30 males, 16 females; 29 limited, 17 extensive stage; 35 Eastern Cooperative Oncology Group performance status 0-1. Positive IHC staining was evident for MMP-1 and -9 in 60% to 70% of tumor cells, and for MMP-11, -13, and -14 and TIMP-2 and -3 in 70% to 100% of tumor cells. Stromal staining of TIMP-1 to -3 was present in less than 30% of specimens. On multivariate analysis, only stage and decreased tumoral expression of TIMP-1 were significant for response (P =.043). Significant factors for survival were tumor stage (P =.0021); weight loss (P =. 013); and high tumor cell expression of MMP-3 (P =.077), MMP-11 (P =. 031), and MMP-14 (P =.019). MMP and TIMP expression did not differ significantly between stages.

CONCLUSION

MMPs and TIMPs are widely expressed in SCLC. Increased tumoral expression of MMP-3, -11, and -14 were independent negative prognostic factors for survival. The results support the evaluation of synthetic MMP inhibitors in patients with SCLC.

Pre-hospital thrombolysis

The administration of thrombolytic drugs outside hospital by emergency physicians is becoming more common. However, few in Europe live in areas where such a service is provided. The data suggest that the advantages can be appreciable in some circumstances but that the strategy may not be universally applicable.