Can randomised trials rely on existing electronic data? A feasibility study to explore the value of routine data in health technology assessment

OBJECTIVES

To estimate the feasibility, utility and resource implications of electronically captured routine data for health technology assessment by randomised controlled trials (RCTs), and to recommend how routinely collected data could be made more effective for this purpose.

DATA SOURCES

Four health technology assessments that involved patients under care at five district general hospitals in the UK using four conditions from distinct classical specialties: inflammatory bowel disease, obstructive sleep apnoea, female urinary incontinence, and total knee replacement. Patient-identifiable, electronically stored routine data were sought from the administration and clinical database to provide the routine data.

REVIEW METHODS

Four RCTs were replicated using routine data in place of the data already collected for the specific purpose of the assessments. This was done by modelling the research process from conception to final writing up and substituting routine for designed data activities at appropriate points. This allowed a direct comparison to be made of the costs and outcomes of the two approaches to health technology assessment. The trial designs were a two-centre randomised trial of outpatient follow-up; a single-centre randomised trial of two investigation techniques; a three-centre randomised trial of two surgical operations; and a single-centre randomised trial of perioperative anaesthetic intervention.

RESULTS

Generally two-thirds of the research questions posed by health technology assessment through RCTs could be answered using routinely collected data. Where these questions required analysis of NHS resource use, data could usually be identified. Clinical effectiveness could also be judged, using proxy measures for quality of life, provided clinical symptoms and signs were collected in sufficient detail. Patient and professional preferences could not be identified from routine data but could be collected routinely by adapting existing instruments. Routine data were found potentially to be cheaper to extract and analyse than designed data, and they also facilitate recruitment as well as have the potential to identify patient outcomes captured in remote systems that may be missed in designed data collection. The study confirmed previous evidence that the validity of routinely collected data is suspect, particularly in systems that are not under clinical and professional control. Potential difficulties were also found in identifying, accessing and extracting data, as well as in the lack of uniformity in data structures, coding systems and definitions.

CONCLUSIONS

Routine data have the potential to support health technology assessment by RCTs. The cost of data collection and analysis is likely to fall, although further work is required to improve the validity of routine data, particularly in central returns. Better knowledge of the capability of local systems and access to the data held on them is also essential. Routinely captured clinical data have real potential to measure patient outcomes, particularly if the detail and precision of the data could be improved.

Costs and consequences of different chemotherapy regimens in metastatic colorectal cancer

An economic sub-study was run alongside a large multi-centre randomised trial (MRC-CR06) comparing three chemotherapy regimens; de Gramont, Lokich and raltitrexed in patients with metastatic colorectal cancer. Patients in six of 45 centres in the main trial were approached to take part in the sub-study. Chemotherapy delivery costs were assessed in each sub-study centre with external validity verified by questionnaire to all other centres. Patient representativeness was assessed. Stochastic resource use data, including patient borne costs and non-hospital health service resource use were monitored prospectively. Mean total societal costs were de Gramont= 5051 pounds sterling (s.d. 1910 pounds sterling ), raltitrexed= 2616 pounds sterling (s.d. 991 pounds sterling ) and Lokich= 2576 pounds sterling (s.d. 1711 pounds sterling ). In pairwise comparisons, statistically significant mean total cost differences were shown for de Gramont vs Lokich (mean difference= 2475 pounds sterling , 95%CI 914 pounds sterling - 4037 pounds sterling , P<0.01) and for de Gramont vs raltitrexed (mean difference= 2435 pounds sterling, 95%CI 922 pounds sterling - 2948 pounds sterling , P<0.01). Sensitivity analyses showed little effect on overall costs. The main trial showed de Gramont and Lokich to be equally effective in terms of survival, quality of life and response rates but Lokich had higher toxicity and hand-foot syndrome. Raltitrexed showed similar response rates and overall survival but increased toxicity and inferior quality of life making it a clinically inferior regimen despite its ease of administration and costs. For a comparable clinical outcome, Lokich can be administered for approximately half the cost of de Gramont.

Pragmatic randomised trial to evaluate the use of patient held records for the continuing care of patients with cancer

OBJECTIVE

To evaluate the use of a multidisciplinary record held by patients with cancer in the community.

DESIGN

Pragmatic randomised controlled trial.

SETTING

The environs of Swansea in south west Wales.

PARTICIPANTS

501 patients under the care of the Department of Oncology, Singleton Hospital, Swansea.

INTERVENTION

A patient held record used by the patient and healthcare professionals. Main outcome measures-Health related quality of life (EORTC QLQ-C30) measured at entry into the study and at 6 months; patients' views at 6 months; healthcare professionals' views collected after the completion of patient follow up; NHS resource and booklet use.

RESULTS

1148 patients were eligible for the study; 501 were recruited (44%) and 344 completed the study (172 in each group). There was no significant difference between the two groups in change in quality of life or NHS resource use. The patient held record did not have an impact on communication but was significantly helpful to patients in preparing for appointments, reducing difficulties in monitoring their own progress, and helping them to feel more in control (p<0.05). Fifty three percent of patients would have preferred not to have a patient held record. There was a low level of use of the record by healthcare professionals but most of those who remembered using it indicated that they would prefer patients to have it.

CONCLUSIONS

The patient held record is valued by some patients and professionals but has no significant impact on the quality of life of patients or NHS resource use. It has a positive impact on quality by helping patients feel more in control and prepare for meetings with healthcare staff. Patients who find it useful tend to be younger and have more professionals involved in their care. It is recommended that it should be made available to patients on request and used by them according to need.

Pragmatic randomised trial to evaluate the use of patient held records for the continuing care of patients with cancer

OBJECTIVE

To evaluate the use of a multidisciplinary record held by patients with cancer in the community.

DESIGN

Pragmatic randomised controlled trial.

SETTING

The environs of Swansea in south west Wales.

PARTICIPANTS

501 patients under the care of the Department of Oncology, Singleton Hospital, Swansea.

INTERVENTION

A patient held record used by the patient and healthcare professionals. Main outcome measures-Health related quality of life (EORTC QLQ-C30) measured at entry into the study and at 6 months; patients' views at 6 months; healthcare professionals' views collected after the completion of patient follow up; NHS resource and booklet use.

RESULTS

1148 patients were eligible for the study; 501 were recruited (44%) and 344 completed the study (172 in each group). There was no significant difference between the two groups in change in quality of life or NHS resource use. The patient held record did not have an impact on communication but was significantly helpful to patients in preparing for appointments, reducing difficulties in monitoring their own progress, and helping them to feel more in control (p<0.05). Fifty three percent of patients would have preferred not to have a patient held record. There was a low level of use of the record by healthcare professionals but most of those who remembered using it indicated that they would prefer patients to have it.

CONCLUSIONS

The patient held record is valued by some patients and professionals but has no significant impact on the quality of life of patients or NHS resource use. It has a positive impact on quality by helping patients feel more in control and prepare for meetings with healthcare staff. Patients who find it useful tend to be younger and have more professionals involved in their care. It is recommended that it should be made available to patients on request and used by them according to need.

Marginal-cost contracting in the NHS: results of a preliminary survey

Market disciplines and incentives were expected to improve efficiency in the UK National Health Service following the introduction of an 'internal market' in 1991. An exploratory survey of all Health Authorities and Trusts in the UK was undertaken to investigate whether players in the NHS managed market are behaving as economic theory predicts they should. The focus was on how and to what extent marginal costing has been used in the contracting process and on whether in some instances an inappropriate use of marginal costing may be resulting in inappropriate investment decisions. Twenty of 29 responding Health Authorities (69%) and 16 of 39 Trusts (41%) stated that they had considered purchasing/providing services on a marginal-cost basis and all of these led to contracts. Marginal-cost contracting appears to be fairly commonplace and the process does not appear to be causing insurmountable conflicts between players. Most marginal-cost contracts were specifically to meet waiting-list initiative targets. Overall results suggest that economic principles are not being particularly adhered to, with expansion in output rarely being related to available capacity. As increased responsibility for commissioning passes to primary care teams and local health groups, there are lessons for those involved in this more disaggregated approach to service shaping and service delivery.

Marginal-Cost Contracting in the NHS: Results of a Preliminary Survey

Market disciplines and incentives were expected to improve efficiency in the UK National Health Service following the introduction of an ‘internal market’ in 1991. An exploratory survey of all Health Authorities and Trusts in the UK was undertaken to investigate whether players in the NHS managed market are behaving as economic theory predicts they should. The focus was on how and to what extent marginal costing has been used in the contracting process and on whether in some instances an inappropriate use of marginal costing may be resulting in inappropriate investment decisions. Twenty of 29 responding Health Authorities (69%) and 16 of 39 Trusts (41%) stated that they had considered purchasing/providing services on a marginal-cost basis and all of these led to contracts. Marginal-cost contracting appears to be fairly commonplace and the process does not appear to be causing insurmountable conflicts between players. Most marginal-cost contracts were specifically to meet waiting-list initiative targets. Overall results suggest that economic principles are not being particularly adhered to, with expansion in output rarely being related to available capacity. As increased responsibility for commissioning passes to primary care teams and local health groups, there are lessons for those involved in this more disaggregated approach to service shaping and service delivery.

AAV-mediated delivery of ciliary neurotrophic factor prolongs photoreceptor survival in the rhodopsin knockout mouse

Retinitis pigmentosa (RP), an inherited retinal degenerative disease causing blindness, is characterized by progressive apoptotic death of photoreceptors. Therapeutic modification of photoreceptor apoptosis may provide an effective therapy for this disorder. Ciliary neurotrophic factor (CNTF) has been shown to promote survival of a number of different neuronal cell types, including photoreceptors. The present study aimed to test whether adeno-associated virus (AAV)-mediated delivery of the gene encoding CNTF delays photoreceptor death in the rhodopsin knockout (opsin(-/-)) mouse, an animal model of RP. The vector was made to express a secretable form of CNTF in tandem with a marker GFP. Cultured 293 cells transduced with this virus expressed both CNTF and GFP. The conditioned media from such cells supported the survival of chick dorsal root ganglion neurons in the same manner as recombinant CNTF. Subretinal administration of this virus led to efficient transduction of photoreceptors as indicated by GFP fluorescence and CNTF immunostaining. Histologic examination showed significant photoreceptor preservation in the injected quadrant of the retina. This protection lasted through termination of the experiment (3 months). AAV-mediated delivery of CNTF may have implications for the treatment of human retinal degeneration.

Association of histologic features and cytogenetic abnormalities in ectopic pregnancies

OBJECTIVE

To evaluate the association between specific histologic features and cytogenetic abnormalities in ectopic pregnancies.

DESIGN

Blinded histologic analysis.

SETTING

University hospital.

PATIENT(S)

Fifty-four patients with ectopic pregnancy for whom successful karyotypes and sufficient histologic material were available.

INTERVENTION(S)

Histologic evaluation of chorionic villi from ectopic pregnancies was done by two pathologists who were unaware of the cytogenetic outcome. Seventeen histologic features were evaluated: villus size, villus contour, ghost villi, hydropic villi, trophoblastic hyperplasia, trophoblastic hypoplasia, syncytial knots, Hofbauer cells, blood vessels, trophoblastic lacunae, trophoblastic inclusions or cisterns, degeneration, fibrohyalinization, microcalcifications, and perivillous and intervillous fibrin deposits.

MAIN OUTCOME MEASURE(S)

The association between histopathologic features and cytogenetic outcome.

RESULT(S)

The presence of ghost villi and intervillous or perivillous fibrin was found to be associated with cytogenetic abnormalities. These features are associated with previous fetal cell death.

CONCLUSION(S)

This study does not support an association between specific histologic features of chorionic villi and cytogenetic abnormalities in ectopic pregnancies. The only histologic features that were associated with cytogenetic abnormalities (i.e., ghost villi and intervillous and perivillous fibrin) are merely a result of previous fetal cell death.

Evaluation of clitoral blood flow by color Doppler ultrasonography

The feasibility of reliably measuring clitoral blood flow using standard color Doppler ultrasonography was evaluated by two independent assessors in a sample of 40 pre- and post-menopausal women. High positive correlations with no significant mean differences between examiners were found for three major standard blood flow measures including maximum velocity, resistance, and pulsatility indices. With further methodological refinements, ultrasonographic evaluation of clitoral blood flow will be adaptable for clinical and research use and is likely to become the standard physiological measure of female sexual arousal.

Expression of two novel mouse Iroquois homeobox genes during neurogenesis

Members of the Drosophila Iroquois homeobox gene family are implicated in the development of peripheral nervous system and the regionalization of wing and eye imaginal discs. Recent studies suggest that Xenopus Iroquois homeobox (Irx) genes are also involved in neurogenesis. Three mouse Irx genes, Irx1, Irx2 and Irx3, have been previously identified and are expressed with distinct spatio-temporal patterns during neurogenesis. We report here the cloning and expression analysis of two novel mouse Irx genes, Irx5 and Irx6. Although Irx5 and Irx6 proteins are structurally more related to one another, we find that Irx5 displays a developmental expression pattern strikingly similar to that of Irx3, whereas Irx6 expression resembles that of Irx1. Consistent with the notion that Mash1 is a putative target gene of the Irx proteins, all four Irx genes display an overlapping expression pattern with Mash1 in the developing CNS. In contrast, the Irx genes and Mash1 are expressed in complementary domains in the developing eye and olfactory epithelium.

Open access follow up for inflammatory bowel disease: pragmatic randomised trial and cost effectiveness study

OBJECTIVE

To evaluate whether follow up of patients with inflammatory bowel disease is better through open access than by routine booked appointments.

DESIGN

Pragmatic randomised controlled trial.

SETTING

Two district general hospitals in Swansea and Neath, Wales.

PARTICIPANTS

180 adults (78 with Crohn's disease, 77 ulcerative or indeterminate colitis, 25 ulcerative or idiopathic proctitis) recruited from outpatient clinics during October 1995 to November 1996.

INTERVENTION

Open access follow up according to patient need.

MAIN OUTCOME MEASURES

Generic (SF-36) and disease specific (UK inflammatory bowel disease questionnaire UKIBDQ) quality of life, number of primary and secondary care contacts, total resource use, and views of patients and general practitioners.

RESULTS

There were no differences in generic or disease specific quality of life. Open access patients had fewer day visits (0.21 v 0. 42, P<0.05) and fewer outpatient visits ( 4.12 v 4.64, P<0.01), but some patients had difficulty obtaining an urgent appointment. There were no significant differences in specific investigations undertaken, inpatient days, general practitioner surgery or home visits, drugs prescribed, or total patient borne costs. Mean total cost in secondary care was lower for open access patients (P<0.05), but when primary care and patient borne costs were added there were no significant differences in total costs to the NHS or to society. General practitioners and patients preferred open access.

CONCLUSIONS

Open access follow up delivers the same quality of care as routine outpatient care and is preferred by patients and general practitioners. It uses fewer resources in secondary care but total resource use is similar. Better methods of ensuring urgent access to outpatient clinics are needed.

Multi-disciplinary research can be more than parallel-disciplinary research: the case of GPs' use of magnetic resonance imaging

OBJECTIVES

We aimed to show how in multi-disciplinary research data collected to meet the needs of one discipline can provide information of value to another.

METHODS

Using the critical incident technique, 25 GPs were interviewed about recent scans requested for patients with knee and lumbar spine complaints. Transcripts of the interviews were scrutinized from both a medical and an economic perspective.

RESULTS

Five key economic issues where further research is needed were identified.

CONCLUSIONS

The total value of the information provided by multi-disciplinary research may exceed the sum of the information collected to meet the requirements of the individual disciplines.

Overexpression of fra-2 in transgenic mice perturbs normal eye development

The major components of transcription factor AP-1 (Activator Protein 1) are encoded by the two families of genes related to the proto-oncogenes c-fos and c-jun. The fos-related antigen-2 (fra-2) gene is the most recently described member of the Fos family. To determine the oncogenic potential of fra-2, transgenic mice were generated which over-express fra-2 in a number of tissues. No tumours were evident in any transgenic mice up to 18 months of age, although eye development was severely disrupted in these animals. Corneal abnormalities could be observed histologically as early as embryonic day 15.5 and eyelid fusion failed to occur. Adult eyes were characterized by generalized anterior segment dysgenesis similar to that previously reported in transgenic mice over-expressing transforming growth factor alpha (TGF alpha), and occasionally microphthalmia. Expression of fra-2 was shown to increase following TGF alpha treatment of cells in vitro, suggesting that AP-1 complexes containing Fra-2 contribute to TGF alpha signalling events.

Transcriptional regulation in the immune system: all roads lead to AP-1

The mechanisms regulating the development and function of the immune system are diverse and complicated. The signaling pathways and target genes that become activated upon cell-surface stimulation are currently being defined, and transcription factor activator protein 1 (AP-1) is proving to be an important regulator of nuclear gene expression in leukocytes. In vitro and in vivo studies have demonstrated that AP-1 expression is induced after a diverse range of stimuli and that AP-1 contributes to the regulation of a large number of genes. In this review we will examine the role of AP-1 during leukocyte activation and differentiation in the immune system.

Arrhythmogenic right ventricular dysplasia and anterior polar cataract

Arrythmogenic right ventricular dysplasia (ARVD) is an autosomal dominant inherited cardiomyopathy with incomplete penetrance and variable expressivity. Recently, the gene was mapped to 14q23-24. It is being increasingly investigated as a major cause of sudden death at a young age. Anterior polar cataract (APC) is a rare hereditary form of lens opacity. The locus for an APC gene was located tentatively on 14q24qter. We describe a patient with a severe form of ARVD in whom asymptomatic APC was detected by an ophthalmologic examination. His sister had ARVD and similar cataracts. Parents were second cousins but were healthy. This is the first report of possible autosomal recessive inheritance of ARVD. This is also the first time that the combination of ARVD and APC is reported. Three possibilities may explain this concurrence: pleiotropy, contiguous gene syndrome, or coincidence. Our findings suggest placement of an APC gene at 14q23-24.

Biopsychosocial profile of women with dyspareunia

OBJECTIVE

To compare biopsychologic profiles of women with dyspareunia with a matched no-pain control sample, and to determine whether dyspareunia subtypes based on physical findings have different psychosocial profiles from matched controls.

METHODS

One hundred and five women with dyspareunia and 105 matched no-pain control women underwent standard gynecologic examination, endovaginal ultrasound, and colposcopy. They also completed a structured interview inquiring about pain other than dyspareunia, sexual function, and history of abuse, the Brief Symptom Inventory, the Sexual Opinion Survey, and the Locke-Wallace Marital Adjustment Scale.

RESULTS

In comparison with women who do not experience pain with intercourse, the dyspareunia sample was found to have more physical pathology on examination, and they reported more psychologic symptomatology, more negative attitudes toward sexuality, higher levels of impairment in sexual function, and lower levels of marital adjustment. They did not report more current or past physical or sexual abuse. However, when the undifferentiated dyspareunia sample was divided into subtypes based on physical findings from the gynecologic examinations, the pattern of significant differences from controls varied according to dyspareunia subtype. Elevated psychologic symptomatology and relationship maladjustment were confined to the subtype with no discernible physical findings who reported levels of sexual function not significantly different from matched controls. The vulvar vestibulitis subtype suffered the highest levels of sexual impairment, although this subtype was not characterized by higher levels of psychologic symptoms than controls.

CONCLUSION

As an undifferentiated group, women with dyspareunia have more physical pathology, psychologic distress, sexual dysfunction, and relationship problems. However, this pattern of differences appears to vary depending on the presence and type of physical findings evident on examination. Dyspareunia is a heterogeneous disorder requiring comprehensive gynecologic and psychosocial assessment to determine differentiated treatment strategies.

The binding of a Fos/Jun heterodimer can completely disrupt the structure of a nucleosome

An important first step in the chromatin remodelling process is the initial binding of a transcriptional activator to a nucleosomal template. We have investigated the ability of Fos/Jun (a transcriptional activator involved in the signal transduction pathway) to interact with its cognate binding site located in the promoter region of the mouse fos-related antigen-2 (fra-2) promoter, when this site was reconstituted into a nucleosome. Two different nucleosome assembly systems were employed to assemble principally non-acetylated or acetylated nucleosomes. The ability of Fos/Jun to interact with an acetylated or an unacetylated nucleosome differed markedly. Fos/Jun bound to an unacetylated nucleosome with only a 4- to 5-fold reduction in DNA binding affinity compared with naked DNA. Strikingly, the binding of Fos/Jun to a single high-affinity site incorporated into an acetylated nucleosome resulted in the complete disruption of nucleosomal structure without histone displacement. Moreover, this disruption was sufficient to facilitate the subsequent binding of a second transcription factor.

Analysis of the role of Amh and Fra1 in the Sry regulatory pathway

Sry is the Y-chromosomal gene responsible for initiating the pathway of male development in mammals, presumably by regulating downstream target genes. As a basis for examining the role played by Sry and other candidate sex-determining genes, we have used reverse-transcriptase PCR to produce a precise temporal profile of expression of Sry in the developing gonad. Sry expression first occurs at 10.5 days postcoitum (dpc) and is upregulated to reach a maximum level from 11.25 to 12 dpc. Expression is then steadily downregulated from 12.25 to 13.25 dpc and is completely extinguished by 13.5 dpc. Two genes implicated in sexual development are Amh, encoding anti-müllerian hormone (AMH), and Fra1, encoding Fos-related antigen-1. Expression profiles of Amh and Sry in fetal gonads indicate a possible role for AMH in the downregulation of Sry expression. We show, however, that the timing of Sry downregulation is unaffected in Amh-deficient mice, excluding a role for AMH as a negative regulator of Sry. Further, we have examined the possibility that SRY may activate Fra1 during testis determination by analysing the expression of Fra1 in mouse fetal gonads. Fra1 is not expressed at any stage at or around the critical period of sex determination when Sry transcripts are present, thus excluding a role for Fra1 in sex determination and differentiation.

CRF stimulates expression of multiple fos and jun related genes in the AtT-20 corticotroph cell

Recent studies have shown that corticotropin releasing factor (CRF) stimulates c-fos gene expression in the AtT-20 corticotroph cell line, and that overexpression of c-Fos results in activation of POMC gene transcription. Since transactivation by c-Fos requires dimerization with a Jun family member to form the active transcription factor AP-1, we have examined the expression of multiple fos and jun related genes and have correlated their expression with AP-1 DNA binding activity in AtT-20 nuclear extracts after stimulation with CRF. Although basal expression of c-fos mRNA was extremely low, it was rapidly and transiently stimulated in AtT-20 cells following administration of either constant or a single pulse of CRF. In contrast, basal expression of c-jun mRNA was slightly higher and underwent little or no change in response to CRF. Specific ribonuclease protection analysis showed that in addition to c-fos, mRNA transcripts encoding fos B and jun B were rapidly stimulated in response to CRF, though levels of induced fos B mRNA were 20-40 times lower than c-fos or jun B, respectively. Gel shift analysis demonstrated that CRF caused a sustained increase in AP-1 DNA binding to both a canonical AP-1 element as well as to the POMC exon-1 AP-1 site. Studies with specific antisera directed against c-Fos revealed that although no c-Fos could be detected in AP-1 complexes in basal cell extracts, c-Fos became a prominent component of AP-1 following CRF stimulation, reaching maximal levels by 4 h. Despite the fact that AP-1 DNA binding activity remained elevated for at least 24 h after CRF, c-Fos was most prominent during the early phase of the response. Similarly, JunB was shown to be a major component of AP-1 DNA binding activity in CRF-stimulated AtT-20 nuclear extracts that persisted for at least 24h after stimulation. Despite the obvious induction of fos B mRNA in response to CRF, FosB protein was not detected in DNA bound AP-1 complexes. These data demonstrate that CRF is a potent stimulus for corticotroph expression of c-fos, jun B and fos B, and suggest that the subsequent increase in AP-1 may play a role in activation of gene expression and/or as a modulator of glucocorticoid receptor function.

Messages from Mid Glamorgan: a multi-programme experiment with marginal analysis

This paper discusses the issues and problems arising from the first attempt to apply marginal analysis across a full range of health care activities within a UK Health District. Following a brief description of the two stage process undertaken in Mid Glamorgan, the paper focuses on the importance of a conducive environment to a successful application of the approach and to three key issues of group composition, group dynamics and openness/explicitness. The paper also addresses two parts of the Mid Glamorgan process which might be of questionable importance; the need for programme budgets prior to the exercise and the relevance of stage II which attempted to interfere with the expressed priorities identified by the expert groups in stage I. The main message is that marginal analysis works in practice as well as being attractive in theory and that much can be achieved even when only crude data on marginal costs and benefits are available. It is more important that priority setting be addressed within an appropriate framework than with accurate data. Marginal analysis provides such a framework.

The use of an endotracheal ventilation catheter for jet ventilation during a difficult intubation

This case report describes the use of an endotracheal ventilation catheter (ETVC) to provide prolonged intraoperative jet ventilation, reintubation and the maintenance of tracheal access following extubation. It emphasizes that excellent oxygenation and ventilation can be achieved but such management can be complicated by a pneumothorax even when the risks are minimized. A 43-yr-old man presented for possible pulmonary sleeve resection. Placement of a double lumen endotracheal tube (DLT) by direct laryngoscopy was unsuccessful due to the inability to visualize the glottis. A 7.5 mm endotracheal tube (ETT) was successfully introduced over a fibreoptic bronchoscope (FOB). An ETVC was passed, permitting manually cycled jet ventilation while general intravenous anaesthesia and muscle relaxation were maintained. The ETT was then withdrawn over the ETVC and jet ventilation continued for approximately 90 min, while attempts at placing a DLT over a now malfunctioning FOB continued. These attempts were eventually abandoned and the patient was returned to the post-anaesthesia care unit (PACU) haemodynamically stable. The trachea was extubated over the ETVC, which remained in situ. A pneumothorax was noted on the postoperative chest x-ray. This case illustrates prolonged intraoperative jet injection via a "jet stylet" with satisfactory ventilation and oxygenation but complicated by a pneumothorax. Also it illustrates a strategy for the management of a "difficult extubation."

Cloning and characterisation of the mouse fra-2 gene

Transcription factor AP-1 is comprised of multiple protein complexes that include members of a family of genes related to the proto-oncogene c-fos. In this report, we have extended the analysis of one member of this family, fos-related antigen-2 (fra-2), by isolating and characterising genomic and cDNA clones encoding the mouse fra-2 homolog. The overall gene structure (number and positions of introns) was similar to that of both the chicken fra-2 gene and other members of the fos family, and the relative positions of putative enhancers in the 5' regulatory region were well conserved between the mouse and chicken fra-2 genes. High levels of fra-2 mRNA were detected in ovary, stomach, small and large intestine, brain, lung and heart. The mouse Fra-2 protein showed 94% and 87.5% conservation with human and chicken Fra-2, respectively, and mouse Fra-2, like the chicken homolog, induced transformation of chicken embryo fibroblasts. The characterisation of the mouse fra-2 gene provides a basis for analysis of Fra-2 function in the whole animal.

SRY protein enhances transcription of Fos-related antigen 1 promoter constructs

In mammals, testis determination is under the control of the chromosome Y-linked SRY gene. Sry is expressed in the fetal mouse just before development of the testis and shows germ-cell-dependent expression in the adult mouse. SRY protein contains a high-mobility-group (HMG)-box DNA-binding domain, and potential target sequences have been identified. The fos-related antigen 1 (fra-1) gene is closely related to the protooncogene c-fos and encodes a component of transcription factor AP-1. Fra-1 is expressed during spermatogenesis, and the promoter of the rat fra-1 gene contains several potential binding sites for members of the HMG-box family of DNA-binding proteins. We demonstrate that purified SRY protein binds strongly to one of the putative fra-1 HMG-box response elements and that SRY enhances the transcription of rat fra-1 promoter constructs in cotransfection experiments. These results suggest that the function of HMG-box transcription factors may be mediated, in part, by activation of members of the AP-1 transcription factor family.

Economic implications of smoking cessation therapies: a review of economic appraisals

There is a paucity of studies on the economics of smoking cessation. Those undertaken have investigated only a narrow range of available interventions, using variable methodologies which make interstudy comparisons problematical. There is a need for more economic appraisal in this area and for greater consistency in the methodologies employed. Growing evidence on the effectiveness of pharmacotherapies has not been matched by evidence of their cost effectiveness, and studies in this area, particularly on transdermal nicotine, are urgently required. Cost-benefit analyses (CBAs) have focused on programmes targeted at pregnant women and indicate that resource savings, mainly from reductions in the number of low birthweight neonates, can exceed the costs of the measures. Efforts to persuade pregnant women to quit thus appear to be highly cost beneficial, but further evidence on the efficiency of measures targeted at other groups or to the general population of smokers is required. Cost-effectiveness analyses (CEAs) suggest that measures targeted at specific groups are more cost effective than those targeted at the general population of smokers, and that the cost effectiveness of such programmes is further improved by providing educational materials that are specific to the targeted groups. Advice on how to maintain abstinence appears to improve the cost effectiveness of help with quitting, and routine advice from physicians to their smoking patients is a cost-effective way of reducing smoking prevalence.

Transcriptional regulation in the testis: a role for transcription factor AP-1 complexes at various stages of spermatogenesis

The products of two proto-oncogenes, c-fos and c-jun, have been implicated in signal transduction pathways as regulators of gene expression. Both proto-oncogenes are members of gene families encoding closely related proteins that together make up transcription factor AP-1. The expression of members of this transcription factor has been associated with cellular pathways that result in both mitosis and differentiation. We have been studying the process of spermatogenesis, which is a complex, continual cycle of cell renewal, proliferation and differentiation. Using a seasonal breeder, the European red fox (Vulpes vulpes), as our model, we have examined the expression of five AP-1 family members (c-fos, fra-1, fra-2, c-jun and junB) with a view to elucidating their role in the regulation of spermatogenesis. Unique patterns of expression, falling into three broad categories, were observed for the five genes: (i) continuous expression throughout the spermatogenic cycle (c-fos); (ii) expression only at times corresponding to the onset and shutdown of spermatogenesis (fra-1, fra-2 and c-jun); and (iii) expression only at the onset of the cycle (junB). Furthermore, the proteins were expressed in both premeiotic and post-meiotic cell types, suggesting a role in haploid, as well as diploid, gene expression in this tissue. The data suggest distinct, although not necessarily unrelated, roles for the different components of transcription factor AP-1 in the regulation of spermatogenesis.

Introducing quality into cost effectiveness

The objective of this study is to explore the problems which can arise when quality issues are introduced without proper analysis of the nature and objectives of health care. The principles of economics are used to explain why the primary output of health care should be perceived in terms of health gained (or maintained). Cost Effectiveness Analysis (CEA) is concerned with achieving a given output at lowest cost. The problems of measuring and valuing health gains, as well as problems arising when a quality dimension is introduced, are discussed with reference to the Quality Adjusted Life Year (QALY) as a measure of health gain. Quality of service provision is normally achieved at an increased cost per QALY. This need not make high quality services inefficient provided care is taken in use of terms and Cost Benefit Analysis (CBA) is used to highlight the value placed on consumer satisfaction.

Induction of c-fos mRNA expression by afterdischarge in the hippocampus of naive and kindled rats

Periodic induction of focal electrical seizure [afterdischarge (AD)] is an absolute prerequisite for the development of kindling, an animal model of complex partial epilepsy. Once established, it is a permanent condition. The mechanism(s) that translate ADs, which last tens of seconds, into life-long alterations in the CNS is unclear. Cellular immediate-early genes have been implicated in the conversion of short-term stimuli to long-term alterations in cellular phenotypes by regulating target gene expression. We have investigated the contribution of one such early gene, c-fos, to this process. The relationship between ADs and expression of c-fos gene in the rat hippocampus, a key structure in kindling development, was studied by analysis of mRNA levels. The low constitutive expression of c-fos mRNA in the hippocampus was not altered by kindling. There was an "all-or-none" relationship between induction of c-fos and the duration of AD. The threshold for induction was approximately 30 s of AD. Above-threshold ADs induced c-fos in both naive and kindled animals to the same extent and with identical temporal profiles. Although the expression of c-fos is unchanged with kindling, c-fos may nonetheless contribute to many long-term changes of kindling, both adaptive and epileptogenic.

Transcriptional activation and repression by Fos are independent functions: the C terminus represses immediate-early gene expression via CArG elements

The Fos-Jun complex has been shown to activate transcription through the regulatory element known as the AP-1 binding site. We show that Fos down regulates several immediate-early genes (c-fos, Egr-1, and Egr-2) after mitogenic stimulation. Specifically, we demonstrate that the target for this repression is a sequence of the form CC(A/T)6GG, also known as a CArG box. Whereas Fos bound to the AP-1 site through a domain rich in basic amino acids and associated with Jun via a leucine zipper interaction, mutant Fos proteins lacking these structures were still capable of causing repression. Furthermore, Jun neither enhanced nor inhibited down regulation by Fos. Critical residues required for repression are located within the C-terminal 27 amino acids of c-Fos, since v-Fos and C-terminal truncations of c-Fos did not down regulate. In addition, transfer of 180 c-Fos C-terminal amino acids to Jun conferred upon it the ability to repress. Finally, Fra-1, a Fos-related protein which has striking similarity to Fos in its C-terminal 40 amino acids, also down regulated Egr-1 expression. Thus, Fos is a transcriptional regulator that can activate or repress gene expression by way of two separate functional domains that act on distinct regulatory elements.

Analysis of dimerization and DNA binding functions in Fos and Jun by domain-swapping: involvement of residues outside the leucine zipper/basic region

The products of two cellular proto-oncogenes c-fos and c-jun form a heterodimeric complex that contribute to the DNA-binding activity referred to as AP-1 (activator protein-1). Two domains have been proposed to be required for heterodimer formation and protein-DNA complex formation. The leucine zipper domain mediated the interaction between the two proteins and a highly basic region immediately N-terminal to the leucine zipper forms a DNA binding domain. To assess the role of these two domains in dimerization and DNA binding and to determine what contribution, if any, is made by residues outside of these regions, we carried out an extensive domain swap analysis. Restriction sites created in the fos and jun cDNAs flanking the basic region and leucine zipper allowed these domains to be swapped between the two proteins either singly or in various combinations with adjacent domains. The chimeric proteins were assayed for their ability to dimerize with each other and to interact with the AP-1 consensus sequence. It was found that two Jun leucine zipper regions could mediate protein dimerization, whereas two Fos leucine zipper regions could not. The dimers formed between two Jun leucine repeats were less stable than those formed between a Fos and a Jun leucine zipper. A conserved His residue seven amino acids C-terminal of the last leucine of the zipper region contributed to the stability of protein-protein interactions. The basic region of both Fos and Jun was found to interact with DNA without the presence of the other, i.e. the combination of two Fos- or two Jun-DNA binding domains could bind to the AP-1 site. However, replacement of the Jun N-terminus with that of Fos resulted in a decrease in DNA binding, indicating that residues outside of the Jun basic region contribute to DNA binding. The results also suggest that the dimerization and DNA binding functions of each protein are not completely independent properties, but that each exerts an influence on the other.

The product of a fos-related gene, fra-1, binds cooperatively to the AP-1 site with Jun: transcription factor AP-1 is comprised of multiple protein complexes

fra-1 encodes a serum-inducible protein (Fra-1) that is antigenically related to Fos. We have characterized Fra-1 expression in serum-stimulated cells using antibodies raised against several regions of this protein. Fra-1, expressed transiently in COS cells or in serum-stimulated rat fibroblasts, undergoes extensive post-translational modification, primarily by phosphorylation of serine residues. It is present in both the nucleus and the cytoplasm and participates in a protein complex with Jun. Using proteins synthesized in reticulocyte lysates, we have shown that Fra-1, like Fos, binds to the AP-1 recognition element cooperatively with Jun. A truncated Fra-1 protein that contains the leucine zipper region but not an adjacent basic amino acid domain, complexes with Jun in vitro but fails to bind AP-1 oligonucleotides. These results demonstrate that Fra-1 contributes to the DNA-binding activity ascribed to transcription factor AP-1.

Fos-associated protein p39 is the product of the jun proto-oncogene

The Fos protein complex and several Fos-related antigens (FRA) bind specifically to a sequence element referred to as the HeLa cell activator protein 1 (AP-1) binding site. A combination of structural and immunological comparisons has identified the Fos-associated protein (p39) as the protein product of the jun proto-oncogene (c-Jun). The p39/Jun protein is one of the major polypeptides identified in AP-1 oligonucleotide affinity chromatography extracts of cellular proteins. These preparations of AP-1 also contain Fos and several FRA's. Some of these proteins bind to the AP-1 site directly whereas others, like Fos, appear to bind indirectly via protein-protein interactions. Cell-surface stimulation results in an increase in c-fos and c-jun products. Thus, the products of two protooncogenes (and several related proteins), induced by extracellular stimuli, form a complex that associates with transcriptional control elements containing AP-1 sites, thereby potentially mediating the long-term responses to signals that regulate growth control and development.

fra-1: a serum-inducible, cellular immediate-early gene that encodes a fos-related antigen

A set of proteins antigenically related to the c-fos protein (Fos) are induced by serum in fibroblasts. To isolate cDNA clones of genes encoding such proteins, a lambda gt11 expression cDNA library constructed from serum-stimulated rat fibroblasts was screened with antibodies raised against a hydrophilic region (amino acids 127 to 152) of Fos. One of the positive clones identified, termed fra-1 (Fos-related antigen) was characterized. It encoded a protein that shared several regions of extensive amino acid homology with Fos (including the region that showed similarity to both the yeast GCN4 regulatory protein and the protein encoded by the jun oncogene), although its nucleotide sequence was considerably diverged from that of the c-fos gene. Only a subset of the agents and conditions that activated c-fos also induced fra-1. Induction of fra-1 expression following serum stimulation was delayed compared with that of c-fos. However, like c-fos, fra-1 was induced rapidly by serum in the presence of protein synthesis inhibitors. Thus, a family of Fos-related, inducible genes are involved in the cellular immediate-early transcriptional response to extracellular stimuli.

A zinc finger-encoding gene coregulated with c-fos during growth and differentiation, and after cellular depolarization

Egr-1 is an early growth response gene that displays fos-like induction kinetics in fibroblasts, epithelial cells, and lymphocytes following mitogenic stimulation. Sequence analysis of murine Egr-1 cDNA predicts a protein with three DNA binding zinc fingers. The human EGR1 gene maps to chromosome 5 (bands 5q23-31). Egr-1 mRNA increases dramatically during cardiac and neural cell differentiation, and following membrane depolarization both in vitro and in vivo. Thus, Egr-1 and c-fos are often coregulated with strikingly similar kinetics. These results, in conjunction with the Egr-1 primary structure, suggest that Egr-1 may function as a transcriptional regulator in diverse biological processes.

Mapping patterns of c-fos expression in the central nervous system after seizure

A dramatic and specific induction of c-fos was observed in identifiable neuronal populations in vivo after administration of the convulsant Metrazole. This effect was time- and dose-dependent and was abolished by prior treatment with the anticonvulsant drugs diazepam or pentobarbital. About 60 minutes after administration of Metrazole, c-fos messenger RNA reached a maximum and declined to basal levels after 180 minutes. A further decrease below that in normal brain was observed before a return to basal levels after 16 hours. While Metrazole still elicited seizures during this period, reinduction of c-fos was largely refractory. At 90 minutes, c-fos protein was observed in the nuclei of neurons in the dentate gyrus, and in the pyriform and cingulate cortices. Subsequently, c-fos protein appeared throughout the cortex, hippocampus, and limbic system. Thus, seizure activity results in increased c-fos gene expression in particular subsets of neurons.

Analysis of Fos protein complexes and Fos-related antigens by high-resolution two-dimensional gel electrophoresis

Protein complexes containing the c-fos protein (Fos) and (Fos)-related antigens were isolated from serum-stimulated fibroblasts and from nerve growth factor plus benzodiazepine-treated pheochromocytoma (PC12) cells, and investigated by high-resolution two-dimensional gel electrophoresis. The results show that Fos is complexed with a basic 39-kDa protein (p39) in fibroblasts, and primarily with an acidic 40-kDa protein (p40) in PC12 cells. Whole cells lysates from both cell types contain p40, suggesting that the interaction of Fos and other cellular proteins is dependent on the differentiated state of the cell. In addition to p39 and p40, a heterogeneous population of polypeptides of approximately 48 kDa are present in Fos complexes isolated from non-denatured extracts of either cell type. These proteins may represent a minor class of Fos-binding proteins. Analysis of extracts prepared under denaturing conditions using antisera raised against a Fos peptide (amino acids 127-152) reveals a series of Fos-related antigens. These antigens are induced, some with a slower kinetics than Fos, in fibroblasts and PC12 cells. Thus, c-fos may represent a marker for a family of genes, some of which are antigenically related, that are part of an early cellular transcriptional response to diverse extracellular stimuli.

Cloning and expression of the rat interleukin-3 gene

Genomic clones carrying the rat interleukin-3 (IL-3) gene have been isolated and the nucleotide sequence of the gene determined. Alignment of this sequence with that of the mouse IL-3 gene has allowed the structure of the rat IL-3 gene to be deduced. The intron-exon boundaries are conserved and extensive nucleotide homology (approx 90%) is present in the 5' flanking region and the portion of the gene coding for the signal peptide. Several proposed regulatory sequences are conserved and an analogous element to the tandem repeat in intron 2 of the mouse gene is also present. The predicted amino acid sequence for mature rat IL-3 shows surprisingly low homology (54%) with its murine counterpart, although all four cysteine residues are conserved. The rat IL-3 gene was expressed in monkey COS-1 cells and colony assays established that rat IL-3 is a multi-lineage haemopoietic growth regulator. There was little cross-reactivity of the respective IL-3 species on mouse and rat bone marrow cells suggesting that rat IL-3, in concert with its receptor, has evolved significantly away from the mouse IL-3/receptor system.

pIN32: a cointegrate plasmid with IncHI2 and IncFII components

An Enterobacter cloacae strain isolated from the faeces of a child with diarrhoea in Indonesia contained a transferable 216 MDa plasmid, pIN32, exhibiting IncHI2 phenotypic characters, including temperature sensitivity of transfer and the expression of H serotype pili at a repressed level. A derivative plasmid (pIN32-1), which had lost the IncHI2 phenotype, and contained only 60 MDa of the original replicon, was obtained after mating at 37 degrees C. It was IncFII, showed regions of homology with plasmid R100, determined IncFII serotype conjugative pili constitutively and was transfer-derepressed. After overnight growth at 37 degrees C in non-selective medium, pIN32 gave rise to another derivative, pIN32-2 (size 184.3 MDa), which retained the IncHI2 phenotype and several other pIN32 characters.

Regulation of the production of granulocyte-macrophage colony-stimulating factor by macrophage-like tumour cell lines

Macrophage tumour cell lines (PU5-1.8, P388D1) produced detectable granulocyte macrophage colony-stimulating (CSF-2) activity measured using a factor-dependent cell line FDC-P1. The production of CSF-2 was enhanced by endotoxin and inhibited by serum, and correlated inversely with [3H]TdR incorporation. mRNA isolated from PU5-1.8 or P388D1 cells initiated CSF-2 production when injected into Xenopus laevis oocytes. The specific activity in this assay was unaltered in mRNA isolated from endotoxin-treated cells. The results suggest that endotoxin acts at a post-transcriptional level.

Utility model of preventive behaviour

The utility model of preventive behaviour is presented as an alternative to psychosociological analysis. All preventive actions are viewed as the consumption of those "goods" that affect the risk of illness or injury. Levels of consumption depend on, inter alia, utility (perceived benefit) and cost. Total utility yielded by risk affecting goods is the sum of that derived from the use value of the good, if any, and that from reduced anxiety which results from reduced risk. Many risk affecting goods are consumed mainly for their use value. An examination of the nature of risk affecting goods is presented, followed by an analysis of the factors that determine the anxiety associated with unwanted outcomes. The utility model places preventive behaviour within the framework of the economic theory of demand. The economic principles used in this analysis are explained and their relevance to the consumption of risk affecting goods is determined.

Molecular cloning of cDNA for murine interleukin-3

The cDNA sequence for murine interleukin-3, one of the colony stimulating factors that regulate haematopoiesis, codes for a polypeptide of 166 amino acids including a putative signal peptide. The predicted amino acid sequence indicates that formation of mature interleukin-3 involves proteolytic removal of not only the signal peptide but additional amino-terminal amino acids.