Fetal circular shunt in Ebstein's anomaly and non-steroidal anti-inflammatory treatment

A circular shunt is a poor prognostic factor associated with Ebstein's anomaly. Targeting the constriction of the ductus arteriosus (DA) in order to limit or resolve the circular shunt, has been shown to improve fetal outcomes. Prenatal non-steroidal anti-inflammatory drugs (NSAIDs) have been known to constrict the DA. Recently, prenatal NSAIDs have been used for that purpose in the treatment of circular shunt. Limited research shows that it may be an effective treatment leading to improved fetal outcomes. In this article, we did an extensive review of literature to describe this therapy's effectiveness and outcomes. 82% of fetuses were able to achieve ductal constriction with prenatal NSAID therapy. For fetuses who achieved ductal constriction, fetal demise was less likely (6%) when compared to those who were unable to achieve the same (50%). Of all the fetuses with hydrops, 50% had resoluation of hydrops with prenatal NSAID treatment.

Impact of Initiating Biologics in Patients With Severe Asthma on Long-Term Oral Corticosteroids or Frequent Rescue Steroids (GLITTER): Data From the International Severe Asthma Registry

BACKGROUND

Effectiveness of biologics has neither been established in patients with high oral corticosteroid exposure (HOCS) nor been compared with effectiveness of continuing with HOCS alone.

OBJECTIVE

To examine the effectiveness of initiating biologics in a large, real-world cohort of adult patients with severe asthma and HOCS.

METHODS

This was a propensity score-matched, prospective cohort study using data from the International Severe Asthma Registry. Between January 2015 and February 2021, patients with severe asthma and HOCS (long-term OCSs for ≥1 year or ≥4 courses of rescue OCSs within a 12-month period) were identified. Biologic initiators were identified and, using propensity scores, matched 1:1 with noninitiators. The impact of biologic initiation on asthma outcomes was assessed using generalized linear models.

RESULTS

We identified 996 matched pairs of patients. Both groups improved over the 12-month follow-up period, but improvement was greater for biologic initiators. Biologic initiation was associated with a 72.9% reduction in the average number of exacerbations per year versus noninitiators (0.64 vs 2.06; rate ratio, 0.27 [95% CI, 0.10-0.71]). Biologic initiators were 2.2 times more likely than noninitiators to take a daily long-term OCS dose of less than 5 mg (risk probability, 49.6% vs 22.5%; P = .002) and had a lower risk of asthma-related emergency department visits (relative risk, 0.35 [95% CI, 0.21-0.58]; rate ratio, 0.26 [0.14-0.48]) and hospitalizations (relative risk, 0.31 [95% CI, 0.18-0.52]; rate ratio, 0.25 [0.13-0.48]).

CONCLUSIONS

In a real-world setting, including patients with severe asthma and HOCS from 19 countries, and within an environment of clinical improvement, initiation of biologics was associated with further improvements across multiple asthma outcomes, including exacerbation rate, OCS exposure, and health care resource utilization.

Effect of Stepping Up to High-Dose Inhaled Corticosteroids in Patients With Asthma: UK Database Study

BACKGROUND

It is unclear whether patients with asthma benefit from stepping up to high-dose inhaled corticosteroids (ICSs).

OBJECTIVE

To determine the effectiveness of stepping up to high-dose ICSs.

METHODS

A historic cohort study of patients with asthma (≥13 years old), identified from 2 large UK electronic medical record databases, was conducted. Patients who remained on medium-dose ICSs were compared with those who stepped up from medium- to high-dose ICSs, whereas patients who stepped up from low- to medium-dose ICSs were compared with those who stepped up from low- to high-dose ICSs. Time to first severe exacerbation (primary outcome) between treatment groups was compared using multivariable Cox proportional hazards models, and the number of exacerbations and antibiotics courses was analyzed using negative binomial regression. Inverse probability of treatment weighting was used to handle confounding.

RESULTS

The mean follow-up time to first exacerbation was 2.7 ± 2.7 years for those who remained on stable medium-dose ICSs and 2.0 ± 2.2 years for those who stepped up from medium- to high-dose ICSs. A similar pattern was noted for those who stepped up from low- to medium-dose ICSs (2.6 ± 2.5 years) and from low- to high-dose ICSs (2.3 ± 2.5 years). Patients who stepped up from medium- to high-dose ICSs (n = 6879) had a higher risk of exacerbations during follow-up compared with those who remained on medium-dose ICSs (n = 51,737; hazard ratio, 1.17; 95% CI, 1.12-1.22). This was similar in patients stepping up from low- to high-dose (n = 3232) compared with low- to medium-dose (n = 12,659) ICSs (hazard ratio, 1.10; 95% CI, 1.04-1.17). A step-up to high-dose ICSs was also associated with a higher number of asthma exacerbations and antibiotics courses. No significant difference in associations was found across subgroups of patients with different blood eosinophil counts.

CONCLUSIONS

We found no evidence that a step-up to high-dose ICSs is effective in preventing future asthma exacerbations.

"Life-changing": the experience of super-responders to biologics in severe asthma

BACKGROUND

There is limited information on the patient's perspective of how biologic treatments impact their lives. We conducted a qualitative study to explore the patient's experience of being considered a super-responder from a quality of life perspective.

METHODS

Patients with severe asthma identified as super-responders were invited to semi-structured interviews conducted online. Participants could bring a family member/friend to the interview. The interviews explored experiences of biologic treatment, were transcribed and underwent thematic analysis.

RESULTS

Twenty-five participants took part in this study. Themes emerged on the impact of biologic treatment for participants and for their friends/family: (i) Words used to describe their often life-changing experiences and (ii) the positive changes noted. Biologic treatment stopped the disruption of family life and social life caused by exacerbations. Improvements in mental health were also noted. Marked individual variations in the way it affected their lives were noted. Most participants noticed improvements 2-3 months after starting their biologic, but some noticed improvement within a few days and others after 6 months.

CONCLUSIONS

Super-responders reported profound but heterogeneous improvements following biologic treatment beyond asthma symptoms and exacerbations including important benefits to social and family life. Improvements may be underestimated as social and family benefits are not reliably measured in current studies with implications for health economic evaluations. Not all patients are super-responders, and excellent responses may be lost in group mean data in trials. Individual time course and response patterns need further elucidation to identify who will respond best to biologics.

Previous tuberculosis disease as a risk factor for chronic obstructive pulmonary disease: a cross-sectional analysis of multicountry, population-based studies

Background

Risk factors for COPD in high-income settings are well understood; however, less attention has been paid to contributors of COPD in low-income and middle-income countries (LMICs) such as pulmonary tuberculosis. We sought to study the association between previous tuberculosis disease and COPD by using pooled population-based cross-sectional data in 13 geographically diverse, low-resource settings.

Methods

We pooled six cohorts in 13 different LMIC settings, 6 countries and 3 continents to study the relationship between self-reported previous tuberculosis disease and lung function outcomes including COPD (defined as a postbronchodilator forced expiratory volume in one second (FEV1)/forced vital capacity (FVC) below the lower limit of normal). Multivariable regressions with random effects were used to examine the association between previous tuberculosis disease and lung function outcomes.

Results

We analysed data for 12 396 participants (median age 54.0 years, 51.5% male); 332 (2.7%) of the participants had previous tuberculosis disease. Overall prevalence of COPD was 8.8% (range 1.7%–15.5% across sites). COPD was four times more common among those with previous tuberculosis disease (25.7% vs 8.3% without previous tuberculosis disease, p<0.001). The adjusted odds of having COPD was 3.78 times higher (95% CI 2.87 to 4.98) for participants with previous tuberculosis disease than those without a history of tuberculosis disease. The attributable fraction of COPD due to previous tuberculosis disease in the study sample was 6.9% (95% CI 4.8% to 9.6%). Participants with previous tuberculosis disease also had lower prebronchodilator Z-scores for FEV1(−0.70, 95% CI −0.84 to −0.55), FVC (−0.44, 95% CI −0.59 to −0.29) and the FEV1:FVC ratio (−0.63, 95% CI −0.76 to −0.51) when compared with those without previous tuberculosis disease.

Conclusions

Previous tuberculosis disease is a significant and under-recognised risk factor for COPD and poor lung function in LMICs. Better tuberculosis control will also likely reduce the global burden of COPD.

Characterization of Patients in the International Severe Asthma Registry with High Steroid Exposure Who Did or Did Not Initiate Biologic Therapy

Background

Many severe asthma patients with high oral corticosteroid exposure (HOCS) often do not initiate biologics despite being eligible. This study aimed to compare the characteristics of severe asthma patients with HOCS who did and did not initiate biologics.

Methods

Baseline characteristics of patients with HOCS (long-term maintenance OCS therapy for at least 1 year, or ≥4 courses of steroid bursts in a year) from the International Severe Asthma Registry (ISAR; https://isaregistries.org/), who initiated or did not initiate biologics (anti-lgE, anti-IL5/5R or anti-IL4R), were described at the time of biologic initiation or registry enrolment. Statistical relationships were tested using Pearson’s chi-squared tests for categorical variables, and t-tests for continuous variables, adjusting for potential errors in multiple comparisons.

Results

Between January 2015 and February 2021, we identified 1412 adult patients with severe asthma from 19 countries that met our inclusion criteria of HOCS, of whom 996 (70.5%) initiated a biologic and 416 (29.5%) did not. The frequency of biologic initiation varied across geographical regions. Those who initiated a biologic were more likely to have higher blood eosinophil count (483 vs 399 cells/µL, p=0.003), serious infections (49.0% vs 13.3%, p<0.001), nasal polyps (35.2% vs 23.6%, p<0.001), airflow limitation (56.8% vs 51.8%, p=0.013), and uncontrolled asthma (80.8% vs 73.2%, p=0.004) despite greater conventional treatment adherence than those who did not start a biologic. Both groups had similar annual asthma exacerbation rates in the previous 12 months (5.7 vs 5.3, p=0.147).

Conclusion

Around one third of severe HOCS asthma patients did not receive biologics despite a similar high burden of asthma exacerbations as those who initiated a biologic therapy. Other disease characteristics such as eosinophilic phenotype, serious infectious events, nasal polyps, airflow limitation and lack of asthma control appear to dictate biologic use.

Expansion of the rare Eucalyptus risdonii under climate change through hybridization with a closely related species despite hybrid inferiority

BACKGROUND AND AIMS

Hybridization is increasingly recognized as an integral part of the dynamics of species range expansion and contraction. Thus, it is important to understand the reproductive barriers between co-occurring species. Extending previous studies that argued that the rare Eucalyptus risdonii was expanding into the range of the surrounding E. amygdalina by both seed and pollen dispersal, we here investigate the long-term fitness of both species and their hybrids and whether expansion is continuing.

METHODS

We assessed the survival of phenotypes representing a continuum between the two pure species in a natural hybrid swarm after 29 years, along with seedling recruitment. The performance of pure species as well as of artificial and natural hybrids was also assessed over 28 years in a common garden trial.

KEY RESULTS

In the hybrid zone, E. amygdalina adults showed greater mortality than E. risdonii, and the current seedling cohort is still dominated by E. risdonii phenotypes. Morphologically intermediate individuals appeared to be the least fit. Similar results were observed after growing artificial first-generation and natural hybrids alongside pure species families in a common garden trial. Here, the survival, reproduction, health and growth of the intermediate hybrids were significantly less than those of either pure species, consistent with hybrid inferiority, although this did not manifest until later reproductive ages. Among the variable progeny of natural intermediate hybrids, the most E. risdonii-like phenotypes were the most fit.

CONCLUSIONS

This study contributes to the increasing number of reports of hybrid inferiority in Eucalyptus, suggesting that post-zygotic barriers contribute to the maintenance of species integrity even between closely related species. However, with fitness rapidly recovered following backcrossing, it is argued that hybridization can still be an important evolutionary process, in the present case appearing to contribute to the range expansion of the rare E. risdonii in response to climate change.

Previous tuberculosis disease as a risk factor for chronic obstructive pulmonary disease: a cross-sectional analysis of multicountry, population-based studies

BACKGROUND

Risk factors for COPD in high-income settings are well understood; however, less attention has been paid to contributors of COPD in low-income and middle-income countries (LMICs) such as pulmonary tuberculosis. We sought to study the association between previous tuberculosis disease and COPD by using pooled population-based cross-sectional data in 13 geographically diverse, low-resource settings.

METHODS

We pooled six cohorts in 13 different LMIC settings, 6 countries and 3 continents to study the relationship between self-reported previous tuberculosis disease and lung function outcomes including COPD (defined as a postbronchodilator forced expiratory volume in one second (FEV₁)/forced vital capacity (FVC) below the lower limit of normal). Multivariable regressions with random effects were used to examine the association between previous tuberculosis disease and lung function outcomes.

RESULTS

We analysed data for 12 396 participants (median age 54.0 years, 51.5% male); 332 (2.7%) of the participants had previous tuberculosis disease. Overall prevalence of COPD was 8.8% (range 1.7%-15.5% across sites). COPD was four times more common among those with previous tuberculosis disease (25.7% vs 8.3% without previous tuberculosis disease, p<0.001). The adjusted odds of having COPD was 3.78 times higher (95% CI 2.87 to 4.98) for participants with previous tuberculosis disease than those without a history of tuberculosis disease. The attributable fraction of COPD due to previous tuberculosis disease in the study sample was 6.9% (95% CI 4.8% to 9.6%). Participants with previous tuberculosis disease also had lower prebronchodilator Z-scores for FEV₁ (-0.70, 95% CI -0.84 to -0.55), FVC (-0.44, 95% CI -0.59 to -0.29) and the FEV₁:FVC ratio (-0.63, 95% CI -0.76 to -0.51) when compared with those without previous tuberculosis disease.

CONCLUSIONS

Previous tuberculosis disease is a significant and under-recognised risk factor for COPD and poor lung function in LMICs. Better tuberculosis control will also likely reduce the global burden of COPD.

Preliminary development of a questionnaire to measure the extra-pulmonary symptoms of severe asthma

Background

Research into the effects of asthma treatments on the extra-pulmonary symptoms of severe asthma is limited by the absence of a suitable questionnaire. The aim was to create a questionnaire suitable for intervention studies by selecting symptoms that are statistically associated with asthma pathology and therefore may improve when pathology is reduced.

Methods

Patients attending a specialist asthma clinic completed the 65-item General Symptom Questionnaire (GSQ-65), a questionnaire validated for assessing symptoms of people with multiple medically unexplained symptoms. Lung function (FEV1%) and cumulative oral corticosteroids (OCS) calculated from maintenance dose plus exacerbations were obtained from clinic records. Pathology was represented by the two components of a principal component analysis (PCA) of FEV1% and OCS. LASSO regression was used to select symptoms that had high coefficients with these two principal components and occurred frequently in severe asthma.

Results

100 patients provided data. PCA revealed two components, one where FEV1% and OCS were inversely related and another where they were directly related. LASSO regression revealed 39 symptoms with non-zero coefficients on one or more of the two principal components from which 16 symptoms were selected for the GSQ-A on the basis of magnitude of coefficient and frequency. Asthma symptoms measured by asthma control questionnaires were excluded. The GSQ-A correlated 0.33 and − 0.34 (p = 0.001) with the two principal components.

Conclusion

The GSQ-A assesses the frequency of 16 heterogenous non-respiratory symptoms that are associated with asthma severity using the statistical combination of FEV1% and OCS.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12890-021-01730-0.

Comparison of the sensitivity of patient-reported outcomes for detecting the benefit of biologics in severe asthma

The sensitivity of patient-reported outcomes (PROs) to detect the effects of treatment change depends on the match between the change in items of the PRO and the change that takes place in a sample of people. The aim of this study is to compare the sensitivity of different PROs in detecting changes following the initiation of biologic treatment in asthma. Methods: Patients starting a biologic treatment as part of clinical care completed the Asthma Control Questionnaire (ACQ-6), the Severe Asthma Questionnaire (SAQ and SAQ-global scores) and the EQ5D (EQ-5D-5L and EQ5D-VAS) at baseline. They completed the ACQ-6, SAQ, SAQ-global and a retrospective global rating of change (GRoC) scale at weeks 4, 8 and 16 and completed the EQ-5D-5L and EQ5D-VAS at week 16. The SAQ-global and EQ5D-VAS differ but both are single item 100-point questions. Sensitivity was measured by Cohen’s D effect size at each of the three time points. Results: 110 patients were recruited. Depending on the time of assessment, effect size varied between 0.45 and 0.64 for the SAQ, between 0.50 and 0.77 for the SAQ-global; between 0.45 and 0.69 for ACQ-6; between 0.91 and 1.22 for GRoC; 0.32 for EQ-5D-5L and 0.49 for EQ5D-VAS. Conclusion: The sensitivity to change of a questionnaire varies with the time of measurement. The three asthma-specific prospective measures (SAQ, SAQ-global and ACQ-6) have similar sensitivity to change. The single-item EQ5D-VAS was less sensitive than the asthma specific measures and less sensitive than the single-item SAQ-global. The EQ-5D-5L was least sensitive.

The Severe Asthma Questionnaire: sensitivity to change and minimal clinically important difference

The Severe Asthma Questionnaire (SAQ) is a validated measure of the health-related quality of life of people living with severe asthma [1]. The minimal clinically important difference (MCID) of the SAQ has not been calculated. The MCID is useful for representing clinical as opposed to statistical significance. There are two main ways of calculating the MCID. Distribution methods define the MCID in terms of the relationship between the distribution of scores and mean change score. These methods are purely statistical and the relationship and formulae that constitute the MCID is determined by convention. By contrast, the anchor method [2] defines the MCID in terms of an independent anchor or criterion. When the anchor is the patient's perception of a just noticeable difference in their condition, then the anchor method has two advantages over the distribution method. First, the MCID is defined by a criterion and, therefore, has criterion validity rather than being only a convention. Second, the MCID is defined in terms of the patient's perception of treatment, and the patient's perception of their treatment is recognised as being an important outcome for clinical decision-making [2]. In this letter we present the MCID of the SAQ using the anchor method.

The Severe Asthma Questionnaire (SAQ) is sensitive to change and clinically significant improvement was detected within 4 weeks of starting biologic therapy. The MCID of the SAQ is 0.5 and of the SAQ-global is 11.https://bit.ly/3poJqcG

Validation of subscales of the Severe Asthma Questionnaire (SAQ) using exploratory factor analysis (EFA)

Background

The Severe Asthma Questionnaire (SAQ) is a health related quality of life (HRQoL) questionnaire validated for use in severe asthma. It is scored using the mean value of 16 items (SAQ score) in addition to a single item global rating of HRQoL (SAQ-global). The aim was to validate clinically relevant subscales using exploratory factor analysis (EFA).

Methods

The SAQ was completed, along with measures of asthma control and EQ5D-5L by patients attending six UK severe asthma centres. Clinical data were included in the analysis. EFA using principal axis factoring and oblimin rotation was used to achieve simple structure of data.

Results

460 patients with severe asthma participated, 65% women, mean age 51 (16–83) years. A three factor solution achieved best fit and showed that the SAQ items formed three distinct but inter-correlated groups of items where items were grouped in a way that was consistent with item content. The three subscales were differentially associated with clinically relevant variables (lung function and mood). Males and females interpreted the question of night disturbance in different ways.

Conclusions

This paper provides a template for best practice in the use of EFA when validating HRQoL subscales. The SAQ can be scored as three subscales with content reflecting three different constructs people with severe asthma use when making judgements about their lives. The subscale ‘My Life’ assesses the impact of severe asthma on different life activities, ‘My Mind’ assesses the perceived emotional impact and ‘My Body’ the impact of extra-pulmonary symptoms and side effects.

Comparison of the effects of pulmonary and extra-pulmonary symptoms on health-related quality of life in patients with severe asthma

OBJECTIVES

To survey the frequency of extra-pulmonary symptoms reported by a sample of patients with severe asthma, their contribution to quality of life and relationship to treatment pathways.

METHODS

Consenting patients (N = 100) attending a severe asthma clinic completed questionnaire measures of extra-pulmonary symptoms (the General symptom Questionnaire, GSQ), pulmonary symptoms (Asthma Control Test, ACT), quality of life (the Severe Asthma Questionnaire, SAQ) and health status (EQ-5D-5L).

RESULTS

A median of 21 extra-pulmonary symptoms were reported per week. GSQ correlated -0.65 with the ACT and 0.69 with the SAQ. Linear regression showed that both the ACT and GSQ were significant predictors of SAQ mean score, p < 0.001. In patients not receiving biologics, those with high cumulative OCS exposure (≥1120 mg per year) had significantly worse scores (p < 0.05) on all questionnaires except the ACT and GSQ compared to those with low cumulative OCS exposure.

DISCUSSION

Extra-pulmonary symptoms were common in this sample of people with severe asthma. Extra-pulmonary and pulmonary symptoms contribute equal variance to the score of HRQoL, showing that they are equally important contributors to patients' experience of severe asthma. Extra-pulmonary symptoms are often overlooked in clinical medicine and in measures of quality of life. Participants receiving biologic treatments had lower extra-pulmonary symptoms possibly indicating that biologics reduce systemic symptoms more effectively than other treatments.

Characterization of Severe Asthma Worldwide: Data From the International Severe Asthma Registry

BACKGROUND

Clinical characteristics of the international population with severe asthma are unknown. Intercountry comparisons are hindered by variable data collection within regional and national severe asthma registries. We aimed to describe demographic and clinical characteristics of patients treated in severe asthma services in the United States, Europe, and the Asia-Pacific region.

METHODS

The International Severe Asthma Registry retrospectively and prospectively collected data in patients with severe asthma (≥ 18 years old), receiving Global Initiative for Asthma (GINA) Step 5 treatment or with severe asthma remaining uncontrolled at GINA Step 4. Baseline demographic and clinical data were collected from the United States, United Kingdom, South Korea, Italy, and the Severe Asthma Web-based Database registry (including Australia, Singapore, and New Zealand) from December 2014 to December 2017.

RESULTS

We included 4,990 patients. Mean (SD) age was 55.0 (15.9) years, and mean (SD) age at asthma onset was 30.7 (17.7) years. Patients were predominantly female (59.3%) and white (72.6%), had never smoked (60.5%), and were overweight or obese (70.4%); 34.9% were at GINA Step 5; and 57.2% had poorly controlled disease. A total of 51.1% of patients were receiving regular intermittent oral corticosteroids, and 25.4% were receiving biologics (72.6% for those at GINA Step 5). Mean (SD) exacerbation rate was 1.7 (2.7) per year. Intercountry variation was observed in clinical characteristics, prescribed treatments, and biomarker profiles.

CONCLUSIONS

Using a common data set and definitions, this study describes severe asthma characteristics of a large patient cohort included in multiple severe asthma registries and identifies country differences. Whether these are related to underlying epidemiological factors, environmental factors, phenotypes, asthma management systems, treatment access, and/or cultural factors requires further study.

Evidence for similarity in symptoms and mechanism: The extra-pulmonary symptoms of severe asthma and the polysymptomatic presentation of fibromyalgia

BACKGROUND

Asthma is a disease of the lung and a systemic disease. Functional disorders are associated with multiple systemic abnormalities that have been explained by complexity models. The aim was to test the similarity in type and aetiology between the extra-pulmonary symptoms of severe asthma and the symptoms of fibromyalgia.

METHODS

One Hundred patients recruited from a specialist severe asthma clinic and 1751 people reporting different functional disorder diagnoses recruited via the internet completed the same 60-item questionnaire. Symptom patterns were compared between groups using a new measure, the symptom pattern similarity index where 0 = no relationship, 1 = identical patterns between groups.

RESULTS

Severe asthma patients report numerous extra-pulmonary symptoms. The similarity index between the symptom pattern of the asthma patients with other groups was irritable bowel syndrome = 0.54, chronic fatigue syndrome = 0.69, and fibromyalgia = 0.75. The index between fibromyalgia and asthma patients with the most and least frequent extra-pulmonary symptoms was 0.81 and 0.55 respectively.

CONCLUSIONS

Patients with severe asthma have numerous extra-pulmonary symptoms similar in type and pattern to the symptoms of fibromyalgia. The similarity of the symptom pattern between asthma and fibromyalgia increases as the number of extra-pulmonary symptoms increases as predicted by network theory and previously shown to be the case with other functional disorders. These findings support the hypothesis that functional disorders and extra-pulmonary asthma symptoms have a common complexity or network aetiology. Evidence based behavioural interventions for fibromyalgia may be helpful for patients with severe asthma reporting extra-pulmonary symptoms.

The construction and validation of the Severe Asthma Questionnaire

The US Food and Drug Administration's procedure for scale validation requires a documented stepwise process of qualitative and quantitative data. The aim of this paper is to provide final quantitative validating data for the Severe Asthma Questionnaire (SAQ).The SAQ, Asthma Control Test, Mini Asthma Quality of Life Questionnaire and EQ-5D-5L were completed by 160 patients attending a severe asthma clinic; 51 patients completed the SAQ on two occasions for test-retest reliability analysis. The SAQ produces two scores, a SAQ score based on the average of 16 items and a SAQ-global score from a single 100-point global quality of life scale.Construct validity was demonstrated by factor analysis of the 16 items, convergent validity by correlations of >0.6 between the SAQ, SAQ-global and other questionnaires, and discriminant validity by the ability of the SAQ and SAQ-global to distinguish between different treatment levels. Test-retest reliability (intra-class correlation) was 0.93 for the SAQ and 0.93 for the SAQ-global, and the alpha coefficient for the SAQ was 0.93.The SAQ was developed using recommended qualitative and quantitative procedures for scale development, and can be used to gain insight into patients' perceptions of how severe asthma and its treatment affects their lives.

How patient participation was used to develop a questionnaire that is fit for purpose for assessing quality of life in severe asthma

BACKGROUND

Previous research shows that existing asthma quality of life questionnaires fail to measure the burden of oral corticosteroids that can be used to treat severe asthma, and are therefore not fit for purpose for severe asthma according to the USA's Federal Drug Authority's (FDA) criteria for content validity. Patient input and documentation of that input is key to achieving content validity according to FDA guidelines. This paper describes the process of constructing a new questionnaire to measure the burden of asthma symptoms and burden of treatment in severe asthma, using criteria specified by the FDA.

METHODS

A draft severe asthma questionnaire (SAQ) was constructed using qualitative input from severe asthma patients who took part in an earlier study. The aim of this study was to improve that draft questionnaire using a further group of patients. In four iterative focus groups, 16 people with severe asthma completed the draft questionnaire, discussed the wording and structure and suggested changes that were incorporated into the final version.

RESULTS

The original intention to ask patients to identify whether problems were caused by asthma symptoms or side effects of medication was abandoned as the attribution of cause was found to be difficult and inconsistent. The recall period of 2 weeks was acceptable but fails to reflect the patients' desire to express the variability of severe asthma. Patients suggested improvements to the wording of the draft questionnaire, including splitting some items in two, combining two items in one, and changes to some of the words in individual items and the response scale.

CONCLUSIONS

The final version of the questionnaire was substantially different from one constructed using only qualitative reports from patients about the quality of life deficits of severe asthma. Patients make a valuable contribution to the questionnaire if they are asked to comment and improve an initial draft and where patients are treated as partners in the process of questionnaire construction, rather than only as a source of information to experts who construct the questionnaire.

Chondroprotection by urocortin involves blockade of the mechanosensitive ion channel Piezo1

Osteoarthritis (OA) is characterised by progressive destruction of articular cartilage and chondrocyte cell death. Here, we show the expression of the endogenous peptide urocortin1 (Ucn1) and two receptor subtypes, CRF-R1 and CRF-R2, in primary human articular chondrocytes (AC) and demonstrate its role as an autocrine/paracrine pro-survival factor. This effect could only be removed using the CRF-R1 selective antagonist CP-154526, suggesting Ucn1 acts through CRF-R1 when promoting chondrocyte survival. This cell death was characterised by an increase in p53 expression, and cleavage of caspase 9 and 3. Antagonism of CRF-R1 with CP-154526 caused an accumulation of intracellular calcium (Ca²⁺) over time and cell death. These effects could be prevented with the non-selective cation channel blocker Gadolinium (Gd³⁺). Therefore, opening of a non-selective cation channel causes cell death and Ucn1 maintains this channel in a closed conformation. This channel was identified to be the mechanosensitive channel Piezo1. We go on to determine that this channel inhibition by Ucn1 is mediated initially by an increase in cyclic adenosine monophosphate (cAMP) and a subsequent inactivation of phospholipase A₂ (PLA₂), whose metabolites are known to modulate ion channels. Knowledge of these novel pathways may present opportunities for interventions that could abrogate the progression of OA.

Multi-component assessment of chronic obstructive pulmonary disease: an evaluation of the ADO and DOSE indices and the global obstructive lung disease categories in international primary care data sets

Suitable tools for assessing the severity of chronic obstructive pulmonary disease (COPD) include multi-component indices and the global initiative for chronic obstructive lung disease (GOLD) categories. The aim of this study was to evaluate the dyspnoea, obstruction, smoking, exacerbation (DOSE) and the age, dyspnoea, obstruction (ADO) indices and GOLD categories as measures of current health status and future outcomes in COPD patients. This was an observational cohort study comprising 5,114 primary care COPD patients across three databases from UK, Sweden and Holland. The associations of DOSE and ADO indices with (i) health status using the Clinical COPD Questionnaire (CCQ) and St George's Respiratory Questionnaire (SGRQ) and COPD Assessment test (CAT) and with (ii) current and future exacerbations, admissions and mortality were assessed in GOLD categories and DOSE and ADO indices. DOSE and ADO indices were significant predictors of future exacerbations: incident rate ratio was 1.52 (95% confidence intervals 1.46-1.57) for DOSE, 1.16 (1.12-1.20) for ADO index and 1.50 (1.33-1.68) and 1.23 (1.10-1.39), respectively, for hospitalisations. Negative binomial regression showed that the DOSE index was a better predictor of future admissions than were its component items. The hazard ratios for mortality were generally higher for ADO index groups than for DOSE index groups. The GOLD categories produced widely differing assessments for future exacerbation risk or for hospitalisation depending on the methods used to calculate them. None of the assessment systems were excellent at predicting future risk in COPD; the DOSE index appears better than the ADO index for predicting many outcomes, but not mortality. The GOLD categories predict future risk inconsistently. The DOSE index and the GOLD categories using exacerbation frequency may be used to identify those at high risk for exacerbations and admissions.

The inevitable drift to triple therapy in COPD: an analysis of prescribing pathways in the UK

BACKGROUND

Real-world prescription pathways leading to triple therapy (TT) (inhaled corticosteroid [ICS] plus long-acting β2-agonist bronchodilator [LABA] plus long-acting muscarinic antagonist) differ from Global initiative for chronic Obstructive Lung Disease [GOLD] and National Institute for Health and Care Excellence treatment recommendations. This study sets out to identify COPD patients without asthma receiving TT, and determine the pathways taken from diagnosis to the first prescription of TT.

METHODS

This was a historical analysis of COPD patients without asthma from the Optimum Patient Care Research Database (387 primary-care practices across the UK) from 2002 to 2010. Patient disease severity was classified using GOLD 2013 criteria. Data were analyzed to determine prescribing of TT before, at, and after COPD diagnosis; the average time taken to receive TT; and the impact of lung function grade, modified Medical Research Council dyspnea score, and exacerbation history on the pathway to TT.

RESULTS

During the study period, 32% of patients received TT. Of these, 19%, 28%, 37%, and 46% of patients classified as GOLD A, B, C, and D, respectively, progressed to TT after diagnosis (P<0.001). Of all patients prescribed TT, 25% were prescribed TT within 1 year of diagnosis, irrespective of GOLD classification (P=0.065). The most common prescription pathway to TT was LABA plus ICS. It was observed that exacerbation history did influence the pathway of LABA plus ICS to TT.

CONCLUSION

Real life UK prescription data demonstrates the inappropriate prescribing of TT and confirms that starting patients on ICS plus LABA results in the inevitable drift to overuse of TT. This study highlights the need for dissemination and implementation of COPD guidelines to physicians, ensuring that patients receive the recommended therapy.

Genetic differentiation in spite of high gene flow in the dominant rainforest tree of southeastern Australia, Nothofagus cunninghamii

Nothofagus cunninghamii is a long-lived, wind-pollinated tree species that dominates the cool temperate rainforests of southeastern Australia. The species' distribution is more or less continuous in western Tasmania but is fragmented elsewhere. However, it is unknown whether this fragmentation has affected the species' genetic architecture. Thus, we examined N. cunninghamii using 12 nuclear microsatellites and 633 individuals from 18 populations spanning the species' natural range. Typical of wind-pollinated trees, there was low range-wide genetic structure (FST=0.04) consistent with significant gene flow across most of the species' range. However, gene flow was not high enough to overcome the effects of drift across some disjunctions. Victorian populations (separated from Tasmania by the 240 km wide Bass Strait) formed a genetic group distinct from Tasmanian populations, had lower diversity (mean allelic richness (Ar)=5.4 in Victoria versus 6.9 in Tasmania) and were significantly more differentiated from one another than those in Tasmania (FST=0.045 in Victoria versus 0.012 in Tasmania). Evidence for bottlenecking was found in small populations that were at least 20 km from other populations. Interestingly, we found little divergence in microsatellite markers between the extremes of genetically based morphological and physiological altitudinal clines suggesting adaptive differentiation is strongly driven by selection because it is likely to be occurring in the presence of gene flow. Even though the cool temperate rainforests of Australia are highly relictual, the species is relatively robust to population fragmentation due to high levels of genetic diversity and gene flow, especially in Tasmania.

Pathogenicity and molecular characteristics of infectious bronchitis virus (IBV) strains isolated from broilers showing diarrhoea and respiratory disease

Abstract 1. The possibility that infectious bronchitis virus (IBV) variants isolated from broilers with enteric and respiratory problems have a different tropism and pathological outcome from those IBV strains causing classical respiratory disease was investigated. 2. IBV variants were isolated from broiler flocks with enteric and respiratory problems in two regions of Brazil. The USP-10 isolate, of enteric origin, was inoculated via the oral oroculonasal routes into IBV-antibody-free broilers and specific pathogen-free (SPF) chickens to determine tissue tropism and pathogenicity and compared with an IBV variant (USP-50) isolated from chickens showing signs of respiratory disease only. 3. Both USP-10 and USP-50 strains caused similar pathological patterns by either route of inoculation. Both variants were detected in respiratory and non-respiratory tissues, including the kidney, intestine and testis. 4. Broilers were more susceptible to infection than SPF chickens, and seroconversion was detected in all of the chicks.

A qualitative study of the impact of severe asthma and its treatment showing that treatment burden is neglected in existing asthma assessment scales

BACKGROUND

People with severe asthma experience significant respiratory symptoms and suffer adverse effects of oral corticosteroids (OCS), including disturbed mood and physical symptoms. OCS impacts on health-related quality of life (HRQoL) have not been quantified. Asthma HRQoL scales are valid as outcome measures for patients requiring OCS only if they assess the deficits imposed by OCS.

AIMS

The aim of this study was to compare the burden of disease and treatment in patients with severe asthma with items in eight asthma-specific HRQoL scales.

METHODS

Twenty-three patients with severe asthma recruited from a severe asthma clinic were interviewed about the impact of their respiratory symptoms and the burden of their treatment. The domains from a thematic analysis of these interviews were compared with the items of eight asthma-specific HRQoL scales.

RESULTS

In addition to the burden caused by symptoms, ten domains of OCS impact on HRQoL were identified: depression, irritability, sleep, hunger, weight, skin, gastric, pain, disease anxiety, and medication anxiety. Some patients experienced substantial HRQoL deficits attributed to OCS. Although all HRQoL scales include some OCS-relevant items, all eight scales fail to adequately assess the several types of burden experienced by some patients while on OCS.

CONCLUSION

The burden of OCS in severe asthma is neglected in policy and practice because it is not assessed in outcome studies. Existing asthma HRQoL scales provide an overly positive estimation of HRQoL in patients with frequent exposure to OCS and underestimate the benefit of interventions that reduce OCS exposure. Changes to existing measurement procedures are needed.

Enteric viruses in Brazilian turkey flocks: single and multiple virus infection frequency according to age and clinical signs of intestinal disease

Poult enteritis complex has been associated with enteritis and reduction in growth rates in commercial turkeys worldwide. Intestinal samples from 76 turkey flocks from different Brazilian states affected or not with intestinal disorders were evaluated for the presence of adenovirus groups 1 and 2 (TAV), astrovirus types 1 and 2 (TAstV-1 and TAstV-2), turkey coronavirus (TCoV), reovirus, rotavirus, and avian nephritis virus (ANV) using PCR. The percentage of positive samples was categorized according to the geographic origin, age of the flocks, and presence of clinical signs of intestinal disease. The percentage of samples that were positive for at least one virus was 93.4%, whereas the percentage of samples that were positive for more than one virus was 69.7%. An average of 3.20 viruses per sample was detected in turkeys in the growing phase of the production cycle (1 to 4 wk of age). The TAstV-1 and TCoV were the most frequently observed viruses in growing phase turkeys and occurred simultaneously in 85% of these samples. In turkeys in the finishing phase of development (5 to 18 wk), a lower average number of viruses was observed (2.41), and the most frequent viruses isolated in these turkeys were TAstV-1 (57.1%) and rotavirus (51.8%). Overall, every virus was detected more frequently in growing phase turkeys than in finishing phase turkeys with the exception of TAV. Samples from flocks exhibiting clinical signs of intestinal disease showed a higher rate of positivity, and TAstV-1, TAstV-2, and TCoV were the most frequently occurring viruses in this cohort. Birds without clinical signs most frequently harbored TAstV-1 and rotavirus. Future studies should focus on the description and elucidation of the role of each virus, as well as the pathogenic and immunological implications of the different combinations of viruses in turkeys.

A comparison of three multidimensional indices of COPD severity as predictors of future exacerbations

BACKGROUND

Prediction of future exacerbations of chronic obstructive pulmonary disease (COPD) is a major concern for long-term management of this disease.

AIM

To determine which of three multidimensional assessment systems (the body mass index, obstruction, dyspnea, and exercise capacity [BODE] index; dyspnea, obstruction, smoking, exacerbations [DOSE] index; or age, dyspnea, obstruction [ADO] index) is superior for predicting exacerbations.

METHODS

This was a 2-year prospective cohort study of COPD patients. Pulmonary function tests, the 6-minute walk distance (6MWD), Modified Medical Respiratory Council (MMRC) dyspnea scores, chest computed-tomography measurements, and body composition were analyzed, and predictions of exacerbation by the three assessment systems were compared.

RESULTS

Among 183 patients who completed the study, the mean annual exacerbation rate was 0.57 events per patient year, which correlated significantly with lower predicted forced expiratory volume in 1 second (FEV1) (P < 0.001), lower transfer coefficient of the lung for carbon monoxide (%DLco/VA) (P = 0.021), lesser 6MWD (P = 0.016), higher MMRC dyspnea score (P = 0.001), higher DOSE index (P < 0.001), higher BODE index (P = 0.001), higher ADO index (P = 0.001), and greater extent of emphysema (P = 0.002). For prediction of exacerbation, the areas under the curves were larger for the DOSE index than for the BODE and ADO indices (P < 0.001). Adjusted multiple logistic regression identified the DOSE index as a significant predictor of risk of COPD exacerbation.

CONCLUSION

In this study, the DOSE index was a better predictor of exacerbations of COPD when compared with the BODE and ADO indices.

Effect of T-cell suppression by cyclosporin on primary and persistent infections of infectious bronchitis virus in chickens

Two-week-old white leghorn (WL) chickens were inoculated intra-nasally with 4.51ogio median ciliostatic doses (CD50) of IBV strain M41. Cyclosporin (CSP) (100 mg/kg body weight) was injected intra-muscularly 3 days before virus infection and every 3 days till day 15 post-infection (p.i.). Significant reduction in proliferation responses of whole blood lymphocytes to a T-cell mitogen, concanavalin A were induced, but not to a B and T-cell mitogen, pokeweed mitogen. Mortality in the IBV + CSP group was 18%, but in the IBV group it was 2%. No significant differences in the total number of virus isolations were seen between the two groups. Virus titres in trachea, lung and kidneys of the T-cell suppressed chickens were slightly higher and histopathological lesions more severe. Thus it appeared that T-cells may play a major role in limiting severity and lethality of IBV infections rather than clearing virus. To confirm this, another experiment was performed in which 2-week-old brown leghorn (BrL) chickens, relatively resistant to IBV were infected with a pool of IBV strains. Mortality was 43% in the IBV + CSP group and zero with IBV alone. Earlier reports using the same pool of IBV strains have shown a mortality of 47% in line 151 chicks, a line sensitive to IBV infection. Thus, a resistant line was induced to behave like a susceptible line by T-cell suppression. Virus titres were always 1 to 3 logs higher in the kidneys of T-cell suppressed BrL chicks. Attempts to induce re-excretion of virus by CSP treatment of WL chickens infected with the IBV strain M41 when 2 weeks old were unsuccessful, but when chicks were infected with the same strain at day-old and given CSP injections from 5 weeks p.i., virus re-excretion was primarily seen from the kidneys and not the caecal tonsil. Thus the kidney appears to be the primary site of IBV persistence. The pathogenesis of the disease in T-cell suppressed chickens is discussed.

Effect of heterophil depletion by 5-fluorouracil on infectious bronchitis virus infection in chickens

An anti-tumour drug, 5-fluorouracil (5 FU) was used to deplete heterophils in 11-day-old white leghorn chickens. The reduction in heterophil numbers was monitored by total and differential white cell counts in the peripheral blood. Three days after injection of 5 FU, when the heterophil numbers were significantly reduced, chickens were infected with the Massachusetts strain of infectious bronchitis virus (IBV). Following infection, although the numbers of birds exhibiting clinical signs (nasal exudate) were significantly higher in the 5 FU treated group, the consistency of the nasal exudate was characteristically thin and watery. No significant differences were seen in the virus titres in trachea, lung and kidney between normal and heteropaenic chickens infected with IBV. However, the epithelial cell damage in the tracheal sections was less in the heterophil-depleted chickens.

An in vitro comparison of the virulence of seven strains of infectious bronchitis virus using tracheal and oviduct organ cultures

The virulence of seven infectious bronchitis virus (IBV) strains for tracheal and oviduct ciliated epithelium was assessed using an in vitro tracheal organ culture (TOC) and oviduct organ culture (OOC) system. The OOC were prepared using oviducts obtained from oestrogen-treated chicks. All strains tested stopped ciliary beating in the oviduct by day 5 post-inoculation (p.i.) and in the trachea by day 3 p.i. This corresponded with the absence of immunofluorescent-stained cells in the epithelium at that time. The time taken for a 50% reduction of relative ciliary activity (RCA) of oviduct cilia was shortest for strain 6 (serotype D207) and longest for strain G (enterotropic variant). Strains 7 (serotype D3896) and M41 were the most pathogenic for tracheal cilia, while strains 6 and G were less pathogenic. A calmod-ulin (CAM) assay was standardized to quantify the epithelial cell damage to oviducts caused by IBV. It was found that strains 6 and M41 were the most pathogenic. The use of time taken to achieve a 50% reduction in RCA and the CAM assay for in vitro pathotyping of IBV isolates is discussed. The susceptibility of OOC or TOC for five IBV strains was compared. It was found that strains 25 and 793B had equal predilection for both, while for 25, G and M41, TOC was more susceptible.

Cross-reactive cellular immune responses in chickens vaccinated with live infectious bronchitis virus vaccine

Two-week-old chickens were vaccinated intra-nasally with a live infectious bronchitis virus (IBV) vaccine (H120). On days 4, 7, 11 and 14 post-vaccination (p.v.) spleen mononuclear cells (MNC) prepared from control and vaccinated chickens were stimulated in vitro with homologous (strain M41) and heterologous (strains 7 and 793/B) virus antigens. Antigen-specific lymphoproliferation and interleukin-2 (IL-2) and interferon-y (IFN) production were used to measure cross-reactive cell mediated immune responses. In antigen-specific lymphoproliferation assays, it was found that while 4/16 vaccinated birds responded to the homologous antigen, only one responded to an heterologous antigen (strain 7). However, IL-2 production was seen in the supernatants of spleen MNC from vaccinated chickens stimulated with all three antigens. Production of IFN was also demonstrated in samples stimulated with the homologous and one heterologous (strain 7) antigen. Thus it appears that, following vaccination of chickens with live IBV vaccine, cross-reactive cellular immune responses occur that vary in magnitude with the strain of IBV used for in vitro stimulation.

Susceptibility of organ cultures from chicken tissues for strains of infectious bronchitis virus isolated from the intestine

Organ cultures were prepared from various levels of intestine and kidney of 2 to 4-week old specific-pathogen-free chickens, and their susceptibility to ten strains of infectious bronchitis virus isolated from the chicken intestine and the Massachusetts strain M41 was investigated. The ability of a virus to grow depended on the strain of virus and size of the inoculum. While proventriculus, bursa and kidney were found to be universally susceptible to all viruses tested, some strains did not grow in caecal tonsils or rectum. Strain M41 showed little difference in pattern of tissue replication compared with several other strains isolated from the gut and actually grew in a wider range than some. Duodenum, jejunum and ileum were found to be non-permissive to all strains tested, even after a high input inoculum.

Microwave or autoclave treatments destroy the infectivity of infectious bronchitis virus and avian pneumovirus but allow detection by reverse transcriptase-polymerase chain reaction

A method is described for enabling safe transit of denatured virus samples for polymerase chain reaction (PCR) identification without the risk of unwanted viable viruses. Cotton swabs dipped in avian infectious bronchitis virus (IBV) or avian pneumovirus (APV) were allowed to dry. Newcastle disease virus and avian influenza viruses were used as controls. Autoclaving and microwave treatment for as little as 20 sec destroyed the infectivity of all four viruses. However, both IBV and APV could be detected by reverse transcriptase (RT)-PCR after autoclaving and as long as 5 min microwave treatment (Newcastle disease virus and avian influenza viruses were not tested). Double microwave treatment of IBV and APV with an interval of 2 to 7 days between was tested. After the second treatment, RT-PCR products were readily detected in all samples. Swabs from the tracheas and cloacas of chicks infected with IBV shown to contain infectious virus were microwaved. Swabs from both sources were positive by RT-PCR. Microwave treatment appears to be a satisfactory method of inactivating virus while preserving nucleic acid for PCR identification.

Derivation and validation of a composite index of severity in chronic obstructive pulmonary disease: the DOSE Index

RATIONALE

Chronic obstructive pulmonary disease (COPD) is increasingly recognized as a multicomponent disease with systemic consequences and effects on quality of life. Single measures such as lung function provide a limited reflection of how the disease affects patients. Composite measures have the potential to account for many of the facets of COPD.

OBJECTIVES

To derive and validate a multicomponent assessment tool of COPD severity that is applicable to all patients and health care settings.

METHODS

The index was derived using data from 375 patients with COPD in primary care. Regression analysis led to a model explaining 48% of the variance in health status as measured by the Clinical COPD Questionnaire with four components: dyspnea (D), airflow obstruction (O), smoking status (S), and exacerbation frequency (E). The DOSE Index was validated in cross-sectional and longitudinal samples in various health care settings in Holland, Japan, and the United Kingdom.

MEASUREMENTS AND MAIN RESULTS

The DOSE Index correlated with health status in all data sets. A high DOSE Index score (> or = 4) was associated with a greater risk of hospital admission (odds ratio, 8.3 [4.1-17]) or respiratory failure (odds ratio, 7.8 [3.4-18.3]). The index predicted exacerbations in the subsequent year (P < or = 0.014).

CONCLUSIONS

The DOSE Index is a simple, valid tool for assessing the severity of COPD. The index is related to a range of clinically important outcomes such as health care consumption and predicts future events.

Re-excretion of infectious bronchitis virus in chickens induced by cyclosporin

Following inoculation of day-old chicks with Moroccan strain 'G' of infectious bronchitis virus (IBV) which has a predilection for the gut, virus was recovered from the trachea up to day 7 and from the cloaca up to day 35. After this no virus could be detected, even following the natural stress of re-housing with unfamiliar birds at 9 weeks. When the birds were 12.5 weeks old, they were injected with cyclosporin, a selective T-cell suppressor. Four of the five birds re-excreted virus very erratically, as did two of five contacts. This was accompanied by the appearance of IBV-specific IgM in the sera of both groups. The results suggest that in long-term infections with IBV, virus persistence is controlled by T lymphocytes.

A comparison of direct electron microscopy, virus isolation and a DNA amplification method for the detection of avian infectious laryngotracheitis virus in field material

Seventy-two post-mortem samples of mainly tracheal tissue from commercial chickens from 25 commercial chicken flocks with suspected infectious laryngotracheitis (ILT) were examined for the presence of the virus using direct electron microscopy (EM), virus isolation (VI) in primary chick embryo liver cell culture and a DNA amplification method (polymerase chain reaction; PCR). ILT virus was identified in 22 outbreaks, and in 58 of the 72 specimens. PCR detected virus in 52 of the 72 specimens and VI was positive in 48. In five instances, VI was positive where the other methods were negative and in three, PCR was the only test positive. Direct EM examination detected virus in only 19 of the 58 positive samples and in no case was EM the only method positive. An advantage of PCR was that it could sometimes detect virus in samples that were too heavily contaminated with bacteria for virus to be isolated and on other occasions it was positive for ILT virus when the only virus that could be detected by growth in tissue culture was adenovirus.

Comparison of cultural methods for primary isolation of infectious laryngotracheitis virus from field material

Primary isolation of infectious laryngotracheitis virus (ILT) from tracheal samples from 11 suspected field outbreaks was attempted using a variety of avian cell cultures, Vero cells and embryonated chicken eggs. Tracheal smears of each field sample were also examined by electron microscopy (EM) for the presence of herpesvirus particles. Chick embryo liver cells (CELi) appeared to be the most rapid and sensitive isolation system of those examined with chick kidney (CK) a satisfactory alternative, both demonstrating virus in all 11 samples on first passage. Chick embryo kidney, chick embryo lung and the dropped chorioallantoic membrane of eggs were all less sensitive. Chick embryo fibroblasts and Vero cells were of no particular value for the primary isolation of ILT virus. EM was a useful method of rapid virus identification and confirmation but at least 3.51og10/0.1ml of infectious virus was required to be detected by this method.

A reverse transcriptase-polymerase chain reaction survey of infectious bronchitis virus genotypes in Western Europe from 2002 to 2006

A survey of infectious bronchitis virus (IBV) genotypes in poultry flocks in selected countries in Western Europe was carried out between March 2002 and December 2006. Identification of IBV was by reverse transcriptase-polymerase chain reaction of RNA extracted from oropharyngeal swabs taken from poultry flocks exhibiting signs of clinical disease thought to be attributable to IBV. Part of the hypervariable S1 gene of IBV was sequenced to differentiate between the various genotypes. During the survey, 4103 samples were processed, of which 2419 (59%) were positive for IBV. The predominant IBV genotypes detected were 793B and Massachusetts. The third and fourth most common genotypes were two new economically important field types: Italy02, and a virus similar to genotypes originally detected in China called QX. Analysis of the partial S1 sequences of the genotypes detected suggested that approximately 50% of all 793B, Massachusetts types and D274 IBVs were identical to the homologous commercially available live vaccines. Since 2004 the prevalence of Italy02 (present in all countries from which samples were received) has been declining in all countries except Spain, where it appeared to be the predominant genotype. Since 2004 an IBV genotype has been detected in Holland, Germany, Belgium and France similar to QX and the incidence has increased. QX was not detected in the United Kingdom or Spain. When detections thought to be attributable to vaccines were removed, the dominant genotype in France and Europe overall was 793B; in Germany, Holland and Belgium, it was QX-like IBV; and in the United Kingdom and Spain the dominant genotype was Italy02. The present study is the first to identify the prevalence of both Italy02 and QX field-type variants in poultry flocks in Western Europe. Several novel genotypes have also been detected.

The isolation and characterisation of six avian infectious bronchitis viruses isolated in Morocco

The first isolation and characterisation of infectious bronchitis (IB) viruses from poultry flocks in Morocco are reported. Five isolates designated D, E, F, H and M were related serologically to the Massachusetts serotype, while the sixth, isolate G, was found to be different from any previously reported serotype of IB virus. Neutralising antibodies to isolate G have been detected in sera collected from commercial flocks in Britain, although the virus has not been isolated. While all six isolates caused respiratory disease typical of IB in experimentally infected 3-week-old specified pathogen-free (SPF) chickens, isolate G was unusual in that it could be isolated from several parts of the alimentary tract for up to 21 days post inoculation, and from the duodenum up to 28 days. H120 vaccines protected chicks challenged with isolates E and F but not isolate G.

Experimental reovirus infection in chickens: observations on early viraemia and virus distribution in bone marrow, liver and enteric tissues

The nature of viraemia and tissue distribution of reovirus were studied in the early phase after oral infection of 1-day-old specific-pathogen-free (SPF) White Leghorn chicks with the R2 strain of avian reovirus. A range of tissues collected up to 3 weeks after infection was titrated for their viral content. Virus was present in the plasma, erythrocyte and mononuclear fractions of the blood within 30 hours post-inoculation (p.i.) and was widely distributed in tissues, including the bone marrow by 3 to 5 days p.i. A greater part of the viraemia was associated with plasma, virus in the blood mononuclear fraction being detected only occasionally. There was more infectious virus in the duodenum than the liver and the highest virus titres were found in cloacal swabs taken 1 to 5 days p.i. It was also evident that virus reached the liver within a very short time after infection (<6 hours p.i.) although the source of this early hepatic virus was considered to be residual inoculum absorbed directly into the portal blood. Viraemic virus titres could not be correlated either with duodenal or hepatic virus titre alone.

Reovirus-induced tenosynovitis in chickens: the effect of breed

The effect of breed of chicken on infection with an arthrotropic avian reovirus strain R2 was studied by oral or footpad inoculation of 1-day-old chicks of the following breeds: (1) specific pathogen-free (SPF) light-hybrid, (2) commercial White Leghorn egg-layer, and (3) commercial Ross I broiler, and observed to 12 weeks of age. Although most inoculated birds of all three breeds developed swelling of one or both legs below the hock joint at 3 to 4 weeks of age, gross lesions of tenosynovitis became progressively more severe and extended above the joints only in broilers, whereas in most orally-infected SPF and commercial light chickens gross lesions were intermittently severe and regressed with time. Cloacal virus shedding continued up to 2 weeks in the lighter breeds and 3 weeks after infection in broilers. From a small proportion of infected chickens, reovirus was also reisolated from heart, pancreas and caecal tonsils. In all breeds, the tissue in which virus persisted longest was the hock joint/tendon. There was a poor correlation between isolation of virus and the presence of gross lesions in chickens of 12 weeks of age, especially in broilers. Virus-neutralisation tests demonstrated that seroconversion in the lighter breeds occurred predominantly at 3 weeks and in broilers at 4 weeks after infection. In all three breeds the footpad infection gave significantly lower growth rates than were found in the control and oral-infection groups. Oral infection had no apparent effect on growth rates. The greater susceptibility of broilers to reovirus infection is discussed.

Reproductive biology in egg-laying mammals

The duck-billed platypus and short-beaked echidna are iconic species in Australia. Their morphology and physiology have puzzled scientists all over the world for more than 200 years. Recent genetic studies, particularly the platypus whole-genome sequencing project, have revealed the molecular basis of some of the extraordinary characteristics of monotremes. This and other works demonstrate the great value of research on our most distantly related mammalian relatives for comparative genomics and developmental biology. In this review we focus on the reproductive biology of monotremes and discuss works that unravel genes involved in lactation, testicular descent, gamete biology and fertilization, and early development. In addition we discuss works on the evolution of the complex sex chromosome system in platypus and echidna, which has also significant impact on our general understanding of mammalian sex chromosomes and sex determination.

Reovirus-induced tenosynovitis in chickens the influence of age at infection

Groups of specific pathogen-free (SPF) light hybrid chickens were infected with an arthrotropic reovirus at 1 day old, or at 2, 4, 6 or 9 weeks of age. In each group, approximately 20 were infected orally and 6 via the footpad. For each age group clinical signs of tenosynovitis, gross and microscopic lesions in the legs, virus excretion in the faeces, virus persistence in the joints, and precipitin response to reovirus were observed over a period of 9 weeks post infection (p.i.). For both routes of infection an age-limited susceptibility was shown, the most serious effects, both in numbers of affected birds and severity of gross lesions including tendon rupture, being seen in the youngest group. Gross lesions were rarely seen after oral infection of 6- and 9-week-old chickens. Footpad inoculation of virus had a more severe effect overall, and extended the age susceptibility, mild leg swellings being seen in some birds infected at 6 and 9 weeks of age. After oral infection, higher virus titres in the faeces and a more prolonged persistence in the gut and hock joint were recorded in chicks infected at 1 day old compared with the other age groups. Also, compared with the older groups, a delayed precipitin response was found in those infected at 1 day old. Footpad inoculation provoked earlier virus replication in the gut and a more rapid precipitin response.

Pathogenicity of latent infectious laryngotracheitis virus in chickens

Groups of specific pathogen-free chickens were inoculated with the same dose of a field strain of infectious laryngotracheitis virus that had either been isolated from tracheal swabs taken from infected birds during acute phase shedding, or that had been isolated during an episode of virus shedding after a latent period of 12 to 17 weeks. Birds in both groups developed characteristic clinical signs of ILT including difficulty in breathing, rales and sneezing. Thus, ILT virus shed after a latent period is capable of causing disease in susceptible birds similar to that seen in the field.