A genome scan for loci influencing total serum immunoglobulin levels: possible linkage of IgA to the chromosome 13 atopy locus

Immunoglobulins play an essential part in the immune system, and immunoglobulin deficiencies can have profound medical consequences. The genetic control and regulation of the immunoglobulin response is therefore of interest. Previous investigations have identified a number of loci influencing total and specific IgE levels. In this study, 80 nuclear families have been examined for linkage of total serum IgA, IgG and IgM levels to a genome-wide panel of microsatellite markers. Potential quantitative trait loci influencing IgA levels have been identified on chromosomes 10 and 13, and possible loci influencing IgG levels were found on chromosomes 3 and 13. No significant linkages to IgM levels were found. The linkage of IgA on chromosome 13 was to a marker previously linked to IgE responses (atopy). Linkage to IgG was in the same region but to a more distal marker. None of the factors known to influence immunoglobulin expression map to the loci identified in the present study. These loci are therefore likely to contain previously unrecognized components of the immunoregulatory system.

Attendance at an asthma educational intervention: characteristics of participants and non-participants

As part of an evaluation of the patient education component of the Australian Asthma Management plan, a randomized, controlled trial of asthma education was conducted in 1994/95 at the outpatient asthma and allergy clinic of The Alfred Hospital, a tertiary referral hospital in Melbourne, Australia. The objective of the study was to investigate which demographic and clinical characteristics were associated with attendance at asthma educational session. A total of 125 asthmatics aged over 16 years agreed to participate in the programme, and full compliance with the programme was 43.2%. Allocation to immediate, rather than delayed, education and age were the only significant predictors of attendance. Subjects randomized to the intervention were approximately three times more likely to attend than control subjects (OR = 3.3, 95% CI 1.5-7.3). Asthmatics over 60 years old were approximately six times more likely to attend (OR = 6.6, 95% CI 2.2-19.8) than the age group 16-30 years. The increasing trend in attendance across age categories was highly significant (P < 0.001). There was no relationship between attendance and gender, medication, atopy, smoking status or the physical accessibility of the hospital. Despite offering incentives and conducting the education sessions at subjects' preferred times, their compliance in attending sessions was poor. Over half of the asthmatics, who had expressed interest, failed to attend for their educational sessions. An alternative strategy is required to improve participation by young and employed asthmatics at hospital-based asthma education programmes.

Testing airway responsiveness using inhaled methacholine or histamine

Airway responsiveness assessed using histamine and methacholine is safe, reproducible and relatively easily undertaken in adults and children. Results are similar for methacholine and histamine although methacholine is better tolerated. Responsiveness is increased in children and the elderly, and in women compared to men, possibly due to body size effects. Baseline lung function confounds the interpretation of airway responsiveness and may explain the effect of smoking in most studies. Results are most usefully expressed as the provocative dose producing a 20% fall in FEV1 (PD20FEV1) or the dose-response slope (DRS). When technical factors are controlled the reproducibility of the test is from one to two doubling doses. Measurements of airway responsiveness have been widely used in clinical and research practice. However, assessing their value in diagnosing asthma is limited by the lack of a gold standard for the definition of asthma. Using a cut-off value of 8 mg/mL or 8 mumol for PD20, the tests will discriminate asthmatic from non-asthmatic subjects (based on questionnaire definitions of asthma) with a sensitivity of around 60% and a specificity of around 90%. These properties of the test result in positive and negative predictive values of 86% and 69% when the prevalence of asthma is high (50%-as in the clinical setting) and 40% and 95% when the prevalence of asthma is low (10%, as in general population studies). In the usual clinical setting, assessing the significance of atypical or non-specific symptoms, the tests are of intermediate value in predicting the presence of asthma and less useful in excluding asthma. The additional benefit of testing airway responsiveness to measuring peak flows or to a trial of therapy has yet to be fully assessed. Testing of airway responsiveness may be of value in assessing occupational asthma, asthma severity and the effects of potential sensitizers or treatments. In research, tests of airway responsiveness are more useful for excluding cases of asthma. In population studies, they serve as an objective marker of abnormal airway function which may be genetically determined and, like allergy, are strongly associated with asthma. The predictive value of airway hyperresponsiveness for the development of airway disease is yet to be clearly established. In epidemiology the benefits of measuring airway responses must be weighed against the added inconvenience and cost that is incurred.

Client Oriented Scale of Improvement (COSI) and its relationship to several other measures of benefit and satisfaction provided by hearing aids

Several methods for measuring the self-reported benefit and satisfaction provided by a hearing aid were compared by administering all methods to each of 98 subjects. Significant correlations between many of the measures and reasonably high test-retest correlations for two of the measures administered twice suggest that most of the measures provide valid estimates of benefit and/or satisfaction. One of the methods included is a new tool called the Client Oriented Scale of Improvement (COSI). In this method, the client effectively writes the self-report questionnaire by nominating up to five listening situations in which help with hearing is required. At the conclusion of rehabilitation, reduction in disability and the resulting ability to communicate in these specific situations is quantified. Based on correlation analysis, the COSI method is as statistically valid as the much longer, more traditional questionnaires. Other features, such as relevance, diagnostic utility, compatibility with normal interviewing techniques, and good test-retest reliability, make it particularly suitable for routine clinical use.

The distribution of eosinophils and lymphocytes in the large and small airways of asthmatics

Airway inflammation in asthma consists of variably increased numbers of mononuclear and polymorphonuclear cells, and there is a growing body of evidence to suggest a primary role for lymphocytes and eosinophils in the pathogenesis of asthma. The aim of this study was to examine the distribution of lymphocytes and eosinophils in the bronchial tree of cases of mild and severe asthma. In cases of fatal asthma (n = 10), nonfatal asthma (sudden nonrespiratory death with a history of asthma n = 10), and control cases (sudden death with no history of respiratory illness, n = 10), lymphocytes and eosinophils were counted in transverse sections of large and small airways stained with haematoxylin and eosin. Cases of fatal asthma had longstanding severe asthma and nonfatal cases generally had mild asthma. Lymphocytes were increased in all airway size groups both in fatal and nonfatal cases of asthma compared to control cases (p < 0.001). Eosinophils were increased (p < 0.001) in all airway size groups in the cases of fatal asthma compared to the nonfatal asthma and control groups, which were similar. These differences between case groups were of similar magnitude, when only a random single airway section from each case in each size group was examined. The numbers of lymphocytes correlated with the number of eosinophils in the fatal asthma group (r = 0.60; p < 0.0001), and to a lesser extent in the nonfatal (r = 0.34; p = 0.001) and control groups (r = 0.32; p = 0.001). These findings suggest that increased numbers of lymphocytes are uniformly distributed in the large and small airways in cases of asthma, independently of asthma severity, and that eosinophil recruitment may be related to asthma severity. Hence, biopsy specimens of the proximal airways are likely to be representative of the cellular infiltrate in large and small airways in mild and severe asthma.

Beyond the market in public service

Critiques of the implementation of a market in health care have so far concentrated on conceptual, practical and ethical objections, it is not a real market, say the theorists; it is not delivering say the realists; it does not have public consent, say the moralists. Argues, from a more fundamental critique: the implementation of the market confuses means with ends. Problems lie not in the introduction of the market-which, is argued, has served well in breaking up the frozen paradigm of the welfare state-but in seeing it as an end state rather than a transition. Posits that this has left us trapped in a scenario about buildings, about restructuring and about contracts instead of resolving chronic human problems of ill health. Postulates that the issue is not to argue for or against the market, or indeed to set it against the alternative of the old welfare state: rather to ask how to learn from this transitional state and how to create the mixed economy which lies beyond both market and welfare state. Drawing on previous work on professional bureaucracies, markets and networks relocates the primary challenge not in managing the market but in meeting need within the remit of public consent.

Expression of a translationally regulated, dominant-negative CCAAT/enhancer-binding protein beta isoform and up-regulation of the eukaryotic translation initiation factor 2alpha are correlated with neoplastic transformation of mammary epithelial cells

A translationally regulated, dominant-negative isoform of CCAAT/enhancer-binding protein beta is expressed in transplantable and primary mouse mammary tumors of different etiologies but is not expressed in preneoplastic mammary hyperplasias or in primary prostate, lung, lens, ovary or lymphoid tumors. The eukaryotic initiation factor 2alpha protein is also expressed at significantly higher levels (69.8 +/- 7.2%) in these mammary tumors compared with normal and hyperplastic tissues. Thus, misregulation of eukaryotic initiation factor 2alpha may promote the expression of a dominant-negative CCAAT/enhancer-binding protein beta isoform, which may inhibit terminal differentiation and facilitate uncontrolled proliferation of mammary epithelial cells.

A genome-wide search for quantitative trait loci underlying asthma

Asthma now affects one child in seven in the United Kingdom. Most cases (95%) of childhood asthma are associated with atopy, the immunoglobulin E (IgE)-mediated familial syndrome of allergic asthma, eczema and rhinitis. Segregation analysis has consistently suggested the presence of major genes influencing atopy and IgE levels, with the expectation that these genes may be identified by positional cloning or the examination of candidate genes. Here we report the results of a genome-wide search for linkage to one qualitative and four quantitative traits associated with allergic (atopic) asthma. We have identified six potential linkages (P<0.001), five of which are to quantitative traits. Monte Carlo simulations show that 1.6 false-positive linkages at this level of significance would be expected from the data. One linkage, to chromosome 11q13, has been established previously. Three of the new loci show evidence of linkage to a second panel of families, in which maternal effects and pleiotropy of linked phenotypes are seen. The results demonstrate the extent and the complexity of the genetic predisposition to asthma.

A dynamical model of the distributed interaction of intracellular signals

The behaviour of cells is coordinated by a large array of different types of intracellular protein kinases, protein phosphatases and second messenger molecules. Current experimental evidence suggests that these kinases, phosphatases and other messengers form a vast complicated interconnected signalling network inside the cell. A generic model of this signalling network is presented which is specifically designed to examine the global properties that can be expected from a model based on the available knowledge of these molecular interactions. Different protein types are represented as nodes in a network that interact via a connection matrix. During interactions, idealised kinases and phosphatases activate and deactivate other protein types by altering the level of phosphorylation of their regulatory sites. The occupancy of regulatory sites on protein kinases and phosphatases in turn determines their activity. Monte Carlo simulations are carried out on ensembles of networks. Steady states and periodic behaviour are observed in these networks. We discuss the potential of this type of model for understanding cell behaviour.

Public perceptions of childhood criminality

This paper begins with the Jamie Bulger murder in Britain in late 1993 and sets out to examine the sociological contexts of the waves of shock and reaction that were manifested in the public perceptions of this event. Traditional conceptions of the child through modernity and their social and moral implications for generating a particular view of innocence and dependency are considered as providing the baseline from which childhood today appears to drift. Public reaction is analysed in terms of mass media content, against a general ignorance of the actual child's point of view. The paper concludes with the broader idea that images of childhood have become closely aligned with expectations of social integration and any fracture of one subsequently threatens the other.

Borderline personality disorder: study in adolescence

The study of the presentation, symptomatology and family characteristics of an exclusively adolescent sample of patients with borderline personality disorder (BPD) was undertaken. Twenty-four cases of borderline personality disorder, 20 females, 4 males, identified using chart review and meeting the criteria of the Diagnostic Interview for Borderlines (DIB) and DSM III-R, were matched with psychiatric controls. Adolescents with borderline personality disorder were found to have high rates of affective symptomatology with Axis I diagnosis of major depressive disorder MDD (DSM-III-R), and high rates of interpersonal psychopathology, i.e., manipulation, devaluation, and a pervasive sense of boredom. The latter seem to be characteristic as for adults with borderline personality disorder. The families were particularly angry and volatile.

Airway structure and inflammatory cells in fatal attacks of asthma

Fatal attacks of asthma usually occur against a background of chronic persistent symptoms, presumably due to chronic airway inflammation and changes in airway wall structure. Death from asthma is usually attributed to excessive airway narrowing due to a combination of muscle spasm and mucous plugging. To test the hypothesis that airway wall structure and/or the inflammatory cell profile are related to the duration of a fatal attack of asthma, inflammatory cell profiles and airway structure were examined in cases of fatal asthma and related to the duration of the fatal attack. In transverse sections of large and small airways from subjects dying from asthma, the numbers of eosinophils, neutrophils and lymphomononuclear cells were counted. The amount of smooth muscle shortening, the areas of airway wall, smooth muscle, mucous gland and cartilage were measured. Cell counts, airway dimensions and muscle shortening were compared in cases dying within 2 h of the fatal attack (short duration) and those dying more than 5 h after the onset of the fatal attack (long duration). In cases with fatal attacks of short duration, the numbers of neutrophils and the mucous gland area were increased and the numbers of eosinophils were reduced compared to cases with fatal attacks of long duration. Lymphocyte numbers, airway wall thickness, the areas of smooth muscle and cartilage and the amount of smooth muscle shortening were similar in the two groups. These findings suggest fatal attacks of asthma may be triggered by an inflammatory stimulus and suggest that increased production of mucous may contribute to sudden death in such cases.

Variability of airway structure and inflammation in normal subjects and in cases of nonfatal and fatal asthma

The quantitative assessment of airway inflammation in patients with apparently similar clinical severity of asthma has yielded variable results. The aim of this study was to assess the variability of inflammatory cell counts and airway structure in large and small airways from subjects with and without asthma, and to calculate the number of cases required to detect significant differences between disease groups. Three serial transverse sections, 20 microns apart, were examined from cartilaginous and membranous bronchioles. Airway dimensions measured were the areas and perimeters defined by the luminal surface of the airway epithelium, basement membrane, outer border of airway smooth muscle, and surrounding border of the airway adventitia. Airway wall components measured were the areas of airway smooth muscle, mucous glands and cartilage. The numbers (per mm of basement membrane) of lymphocytes, eosinophils, neutrophils and plasma cells were counted using haematoxylin and eosin staining and mast cells were counted in sections stained with Toluidine blue. Measurements were repeated by two or three observers. The coefficient of variation (CV) was used to assess intraairway, intraobserver and interobserver variability. For airway dimensions the mean (+/- SD) CV within airways was 3.8% +/- 2.1%, within observers was 3.7% +/- 1.8% and between observers, 3.4% +/- 1.8%. For airway wall components, the CV within airways was 10.7% +/- 4.6%, and between observers was 8.8% +/- 2.2%. For cell counts, the CV within airways was 20.8% +/- 12.5%, within observers was 8.3% +/- 3.7% and between observers, 9.6% +/- 4.6%. There were no significant differences in variability between cases with and without asthma. Intra-airway variability was higher (p < 0.05) in membranous airways (5.6% +/- 1.7%) than in large cartilaginous airways (2.3% +/- 1.1%). We estimate that between 5 and 15 cases in each group would be required to detect differences of 50-100% between groups, depending on the parameter being compared. These findings suggest that airway structure and inflammatory cell numbers are uniform throughout the bronchial tree in normal and asthmatic cases, and that small samples of large or small airways are likely to be representative when comparing cases.

Functional interactions between areas V1 and V2 in the monkey

The role of feedback connections from area V2 to V1 was studied by reversible inactivation. When V2 was inactivated the responses of some V1 neurons to stimulation of the surround region were increased while responses to center stimulation were unchanged or decreased. Latencies to small flashing stimuli were also compared in areas V1 and V2. The distributions in the two areas overlap largely, with a 10 ms shift between the two. Neurons of V1 and V2 that are driven by the magnocellular layers of the LGN are activated 20 ms earlier than neurons of the parvocellular stream.

Office abortion services for women: private physician providers

Research suggests that private physician providers of office abortions and the women who seek their services are not included in nationwide surveys of abortion statistics. This study describes the demographic characteristics of private physicians and the prevalence of abortions performed in their offices in Los Angeles County, California, a state in which office abortions are prohibited by law. Factors that influence physicians' decisions to provide the service, as well as the age and ethnicity of the office abortion recipients, are examined. Of 1,004 California Medical Association members who practiced obstetrics and gynecology in Los Angeles County during 1990, 49% returned anonymous, confidential surveys. Seventy percent of physicians had performed at least one abortion in California, and 29% were currently providing this service in their offices. Physician gender, age, ethnicity, and religion were associated with performing abortions. The average abortion patient was not young and ethnic, but White, middle-class, and in her mid- to late twenties. The implications of these findings are discussed.

Maximum and medium security: the interface

This paper examines transfer delays for patients moving between medium and maximum security hospitals. Delays appear to be getting shorter and Special Hospitals in particular respond very quickly to requests for admission. Recommendations are made for further improvements in transfer procedures. The authors argue that with closer working relationships between clinicians in Special Hospitals and Regional Secure Units, and the new proactive approach to transfers, the system will become increasingly flexible and responsive. Consequent improvements in the quality of care in Special Hospitals are anticipated, making the arguments for closing them, in turn, less convincing.

Detection of a recessive major gene for high IgE levels acting independently of specific response to allergens

The genetic control of the total IgE, the immunoglobulins E involved in allergy, remains still unclear. Although high IgE levels were found to be determined by a recessive major gene in several studies, other modes of inheritance were also reported. Moreover, at least two different genetic mechanisms controlling the IgE regulation have been suggested: one involved in the specific IgE response and the other one in the nonspecific response. To better understand the genetic mechanisms controlling IgE variation, we performed segregation analysis of IgE levels by ignoring or taking into account the specific response to allergens (SRA). Analyses were conducted using the class D regressive model, in a sample of 234 Australian nuclear families randomly selected during the winter months, when IgE levels are the lowest (basal). SRA, when included as a covariate in the model, was defined by one of the three following criteria: (1) raised specific IgE level for one or more allergens, (2) positive skin test for one or more allergens, and (3) at least one of the (1) or (2) criteria. When the presence of SRA is ignored, the familial transmission of total IgE level is compatible with the segregation of a recessive major gene and residual familial correlations. When the presence of SRA is accounted for in the analysis, whether defined by criteria (1), (2), or (3), there is still evidence for a recessive major gene controlling IgE levels but residual familial correlations are no longer significant. In addition, no interaction between this major gene and SRA is shown here. Our results suggest that this gene, which accounts for 28% of the variation of the trait, may be involved in the control of basal IgE production, independently of specific response to allergens.

Giant mucinous ovarian tumor with low malignant potential with foci of well-differentiated mucinous adenocarcinoma masked by massive obesity. A case report

A giant (64-kg) mucinous tumor with low malignant potential and foci of well-differentiated mucinous adenocarcinoma was removed from a massively obese (250 kg) woman. This case represents the largest tumor of this type reported to date.

Effects of lung volume and surface forces on maximal airway smooth muscle shortening

The effects of lung volume and surface forces on airway smooth muscle shortening were studied in isolated perfused rat lungs. The lungs were inflated via the trachea with gas or Krebs solution (n = 12 each) to volumes equivalent to gas inflation pressures of 5 (low), 15 (medium), and 25 (high) cmH2O (n = 4 each). At each volume, two of the four lungs were perfused with methacholine (10(-2) M) and then all were perfused with Formalin for fixation. The amount of smooth muscle shortening present in transverse sections of the airways was determined by comparing the observed outer perimeter of the smooth muscle layer with its calculated relaxed perimeter. In the control lungs, mean shortening was < or = 10% in all groups except the liquid-filled lungs at low lung volumes [33 +/- 12% (SD)]. In the methacholine-stimulated lungs, mean shortening was between 45 and 56% at medium and low lung volumes in gas- and liquid-filled lungs, respectively, and approximated the degree of shortening required to cause airway closure. At high lung volume, less shortening was observed in the methacholine-stimulated lungs, either liquid (34 +/- 17%) or gas filled (16 +/- 19%; P < 0.05 compared with liquid filled). The effects of lung volume in liquid-filled lungs and the differences in response between gas- and liquid-filled lungs demonstrate, respectively, that both lung tissue recoil and surface forces act to oppose shortening of maximally stimulated smooth muscle.(ABSTRACT TRUNCATED AT 250 WORDS)

Reinjury prevention follow-through for clients with cumulative trauma disorders

OBJECTIVES

Fifteen subjects with upper extremity work-related cumulative trauma disorders were involved in a quality improvement study to determine their self-reported degree of follow-through with reinjury prevention regimens. The effect of cuing was also studied.

METHOD

During occupational therapy, subjects were involved in an educational session that focused on recommendations in ergonomic equipment, therapeutic maintenance techniques, body mechanics, and work simplification techniques. Follow-through with reinjury prevention education was evaluated and rated via telephone interviews approximately 2 weeks (T1) and 4 weeks (T2) after the educational session. Subjects did not know the questions they would be asked at T1, but were cued that their progress would be checked again at T2. Dependent t tests were conducted to compare the mean number of recommendations for which complete follow-through was expected with the mean number of recommendations at T1 and T2 that were implemented completely.

RESULTS

A significantly lower degree was found of absolute completion of recommendations at T1 and T2 than had been anticipated (p < .002). No significant difference between T1 and T2 was found, indicating that cuing at T1 had little effect on subjects' actual follow-through rate.

CONCLUSION

The implications of these findings for occupational therapists support the need for further research in reinjury prevention and employer education.

The end of the second most expensive health care system in the world: some geographical implications

In Canada, there has been an increasingly, vociferous debate over the future of a health care system which is based on 5 principles: comprehensiveness; public administration; universality; portability; and accessibility. In part, this debate is a policy tug-of-war among provincial governments, special interest groups and the public who on one side want to maintain the principles of the health care system and on the other want to control costs within the system. The outcome of this policy tug-of-war is demonstrated through an analysis of the funding of health care in the province of Ontario, Canada in general, and the closure of hospital beds specifically. The analysis shows that in attempting to restructure the system, rationalization and growing spatial inequality are occurring simultaneously. The analysis calls into question the whole strategy of bed closures as a method of controlling health care costs. These conclusions have implications for other national health care systems where hospital bed closures have also been used as a strategy in controlling health care costs.

Adolescent onset psychosis. A clinical and outcome study

58 psychotic adolescents between the ages of 12 and 17 diagnosed according to RDC criteria were matched with psychiatric comparisons and followed-up using a two stage design. Information upon the group as a whole was obtained using death records, criminal records and data from the Oxford Record Linkage System. A sub-sample of 21 matched pairs were interviewed using the Schedule for Affective Disorders and Schizophrenia--Life time version (SADS-L) and the Adult Personality Functioning Assessment (APFA). The outcome of adolescent schizophrenia was poor with 78% continuously ill and socially handicapped. Outcome was better for bipolar disorders and schizo-affective disorders and similar to psychiatric comparisons.

Activities of daily living capabilities and values of long-term-care facility residents

OBJECTIVE

The Minimum Data Set for Nursing Home Resident Assessment and Care Screening was used to compare staff-report and self-report of residents' capabilities in eight activities of daily living (ADLs) in one long-term-care facility (LTCF).

METHOD

The relative values residents placed on independence in each of the eight ADLs were compared with their self-reported capabilities in those ADLs. Subjects were 30 LTCF residents ranging in age from 45 to 96 years.

RESULTS

Residents perceived themselves to be significantly more capable than did staff members for dressing (p < .05), toileting (p < .01). locomotion (p < .05), and personal hygiene (p < .001). For five of the ADLs, residents tended to report high capability in the ALDs they valued most.

CONCLUSION

These findings support the need to include resident self-assessment in treatment planning, because staff members' and residents' perceptions of ADL capabilities may differ.

The use of the axial CT scan in intra-articular fractures of the calcaneum

The axial CT scan has become part of our routine management of os calcis fractures. This investigation helps distinguish between tongue and joint depression type fractures, gives important information regarding the fracture pattern in the anterior calcaneum and the degree of comminution of the sustentaculum tali and the subtalar joints. The scan is also useful in determining direction of movement of the body fragment.

Variability of the plateau response to methacholine in subjects without respiratory symptoms

BACKGROUND

Interpretation of measurements of limited maximal airway narrowing, or plateau response, requires knowledge of its variability within subjects and between methods.

METHODS

The repeatability of the plateau response to inhaled methacholine with a dosimeter (D) method (maximal dose 210 mumol) and a tidal breathing (T) method (730 mumol), and the agreement of the two methods, were measured in 16 subjects with mild or no asthma. Two tests by each method (D1,D2,T1,T2) were performed in random order over four consecutive days, with a third dosimeter (D3) test one week later. The dose producing a decrease in forced expiratory volume in one second (FEV1) of 10% (PD10) and the plateau were calculated from each dose-response curve.

RESULTS

A plateau was reached in all five tests in 12 subjects and in all tests except D3 in 14 subjects. PD10 was inversely related to the plateau (r = -0.95 for D, r = -0.77 for T). The 95% ranges for differences between two determinations of the plateau in a subject were +/- 11.9% (change in FEV1), +/- 19.2%, and +/- 20.3%, estimated from D1-2 and 1-3, and T1-2 tests, respectively. From the same tests the 95% ranges for the difference of a single determination from an individual's true mean value were +/- 8.3%, +/- 13.6%, and +/- 14.3%. The limits of agreement between methods indicated that 95% of the measurements of the plateau by tidal breathing ranged from 15.2% below to 13.3% above those obtained by dosimeter. There was no significant bias between methods. Tachyphylaxis over 24 hours occurred with PD10 but not with the plateau response.

CONCLUSIONS

The plateau response is a subject characteristic which is independent of the method of inhalation challenge testing. Repeatability of the plateau is low in this group of subjects with low airway responsiveness.

Transform or die

Regions have an uncertain future in the new NHS. But if they make the right changes, they may yet play a key role, says Ann James.

The structure of large and small airways in nonfatal and fatal asthma

Asthma is characterized by excessive airway narrowing and airway wall inflammation. In cases of fatal asthma, increased thickness of the airway wall is observed and may account for excessive airway narrowing when smooth muscle contracts. This study was undertaken to examine airway dimensions in large and small airways in both fatal and nonfatal cases of asthma. Airway wall areas (total, inner, and outer relative to smooth muscle layer), epithelial integrity, smooth muscle shortening, and the areas of smooth muscle, cartilage, and mucous glands were compared in transverse sections of large and small airways of subjects dying of asthma (fatal asthma, n = 11), those dying suddenly of nonrespiratory diseases and having a definite history of asthma (nonfatal asthma, n = 13), and those dying suddenly without any history of respiratory illness (control, n = 11). Airways were grouped by size using the basement membrane perimeter for comparison. All areas were expressed as areas per millimeter of basement membrane. In cartilaginous airways, the cases of fatal asthma had greater (p < 0.05) total wall, inner wall, outer wall, smooth muscle, mucous gland and cartilage areas than did control and nonfatal cases. The inner wall area was greater in the fatal and nonfatal cases than in the control cases (p < 0.05) in the small cartilaginous airways and membranous bronchioles (MB). In small MB (perimeter < 2 mm), the total and outer wall areas were greater (p < 0.05) in cases of fatal and nonfatal asthma than in control cases.(ABSTRACT TRUNCATED AT 250 WORDS)

Maximal airway narrowing in a general population

To characterize airway responses in a population sample, respiratory symptoms, smoking habits, and changes in FEV1 (delta FEV1) to inhaled methacholine (maximal cumulative dose of 196 mumol or maximal decrease in FEV1 of 50%) were recorded in 201 subjects. From each dose-response curve the plateau (delta FEV1 less than or equal to 5% over two or more dose steps) response, the maximal response (average of responses on the plateau or maximal delta FEV1 when no plateau was present), slope, and PD20 (dose required to cause delta FEV1 greater than 20%) were derived. The pattern of dose-response curves was a continuous change from being flat (maximal delta FEV1 less than or equal to 5%), becoming steeper with a plateau that occurred at a greater change in FEV1 as the curves were shifted more to the left, to being the steepest without a plateau response. Maximal delta FEV1 was significantly related to the PD20 (r = -0.64, p less than 0.001) and the slope (r = 0.63, p less than 0.001). A history of doctor-diagnosed asthma or wheeze in the last 12 months was related to the level of the maximal delta FEV1 and to PD20. Likelihood ratios [LR = sensitivity/(1-specificity)] for asthma or wheeze were higher for a maximal delta FEV1 of 50% plus a PD20 of 4 mumol (LR = 6.5) or 1 mumol (LR = 7) than for either alone. Subjects without reported asthma or wheeze more often had a plateau on the dose-response curve (76%) than those with a positive history (49%, p less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

Has the process causing noninsulin dependent diabetes start at birth? Evidence in neonates from a population with a high prevalence of diabetes

AIMS

to investigate whether differences in the glucose-insulin axis are present at birth in neonates from ethnic groups at high risk of diabetes.

METHODS

fructosamine samples were taken from Maori, European and Pacific Island expectant mothers at their 28 week appointment at the public outpatients clinic at National Women's Hospital, Auckland. Umbilical cord samples for insulin, C-peptide and fructosamine assay were taken at delivery and babies had their subscapular skinfold fat thickness measured by callipers.

RESULTS

the mean maternal 28 week fructosamine was similar in the three populations in spite of a higher prevalence of gestational diabetes among Pacific Islanders. Of the 1066 deliveries, cord samples were available for 207 Europeans, 81 Maoris and 113 Pacific Islanders. Both Pacific Island and Maori babies had higher cord fructosamine concentrations than European babies. However, Pacific Island babies were also heavier, and had higher cord insulin concentrations and subscapular skinfold thickness than European babies.

CONCLUSIONS

the elevated cord fructosamine concentrations suggest that Maori and Pacific Island babies, who share a high risk of noninsulin dependent diabetes mellitus later in life, are hyperglycaemic at birth. The paradoxical insulin results and the cause for the relative neonatal hyperglycemia warrant further investigation.

A model of airway narrowing in asthma and in chronic obstructive pulmonary disease

We have examined the effect of airway wall thickening, loss of lung recoil, and airway smooth muscle shortening on the increase in airway resistance using a model of the human tracheobronchial tree. The values for airway wall thickening were determined morphometrically on the postmortem or surgically resected lungs of normal subjects, patients with moderate chronic obstructive pulmonary disease, and patients with severe asthma. Loss of recoil was simulated by deflating airways along their pressure-area curves by 1 to 3 cm H2O. Values of smooth muscle shortening between 20 and 40% were used in the model to generate sigmoidal-shaped "dose-response" curves. The analysis shows that moderate amounts of airway wall thickening, which have little effect on baseline resistance, can profoundly affect the airway narrowing caused by smooth muscle shortening--especially if the wall thickening is localized in peripheral airways. The combination of a loss of recoil and airway wall thickening are more than additive in their effect on simulated airway responsiveness. We conclude that airway wall thickening and a loss of lung recoil can partially explain the airway hyperresponsiveness observed in patients with chronic obstructive lung disease and asthma.