Economic evaluation of the Very Early Rehabilitation in SpEech (VERSE) intervention

INTRODUCTION

There is limited evidence on the costs and outcomes of patients with aphasia after stroke. The aim of this study was to estimate costs in patients with aphasia after stroke according to the aphasia therapies provided.

METHODS

A three-arm, prospective, randomized, parallel group, open-label, blinded endpoint assessment trial conducted in Australia and New Zealand. Usual ward-based care (Usual Care) was compared to additional usual ward-based therapy (Usual Care Plus) and a prescribed and structured aphasia therapy program in addition to Usual Care (the VERSE intervention). Information about healthcare utilization and productivity were collected to estimate costs in Australian dollars for 2017-18. Multivariable regression models with bootstrapping were used to estimate differences in costs and outcomes (clinically meaningful change in aphasia severity measured by the WAB-R-AQ).

RESULTS

Overall, 202/246 (82%) participants completed follow-up at 26 weeks. Median costs per person were $23,322 (Q1 5,367, Q3 52,669, n = 63) for Usual Care, $26,923 (Q1 7,303, Q3 76,174, n = 70) for Usual Care Plus and $31,143 (Q1 7,001. Q3 62,390, n = 69) for VERSE. No differences in costs and outcomes were detected between groups. Usual Care Plus was inferior (i.e. more costly and less effective) in 64% of iterations, and in 18% was less costly and less effective compared to Usual Care. VERSE was inferior in 65% of samples and less costly and less effective in 12% compared to Usual Care.

CONCLUSION

There was limited evidence that additional intensively delivered aphasia therapy within the context of usual acute care provided was worthwhile in terms of costs for the outcomes gained.

Two-Dye Versus Three-Dye DIGE for Comparative Testis Tissue Proteomic Analysis

The global analysis of the proteome is an important tool in cell biology. Comparative proteomic evaluations can identify and compare the composition, dynamics, and modifications between different samples. Comparing tissue proteomes under different conditions is crucial for advancing the biomedical field. Fluorescence two-dimensional difference gel electrophoresis (2D-DIGE) is a sensitive and robust biochemical method that can compare multiple protein samples over a broad dynamic range on the same analytical gel and can be used to establish differentially expressed protein profiles between different sample groups. 2D-DIGE involves fluorescently labeling protein samples with CyDye flours, via a two-dye or a three-dye system, pre-separation by isoelectric point, and molecular weight. DIGE circumvents gel-to-gel variability by multiplexing samples to a single gel and through the use of a pooled internal standard for normalization, thus enabling accurate high-resolution analysis of differences in protein abundance between samples. This chapter discusses 2D-DIGE as a comparative tissue proteomic technique and describes in detail the experimental steps required for comparative proteomic analysis employing both options of two-dye and three-dye DIGE minimal labeling.

The History of the Post-Graduate Medical and Nursing Officers (PGMNO) course in the British Army

Military medicine has been evolving for over 5000 years of recorded civilisation and conflict. The Army Medical Services performed poorly during the Crimean War and the British Army introduced a professional training course for medical officers in 1860. The Army Medical School and the predecessor of today's Post-Graduate Medical and Nursing Officers (PGMNO) course have had to adapt to changes in British foreign policy and military requirements. The Army Medical School instigated a rigorous scientific medical training which led to major advances in the study of tropical diseases and trauma medicine. These advances were quickly included in the training of future cohorts. Although the Army Medical School has now closed, the PGMNO course thrives at its new location at the Defence Medical Academy, Whittington. Modern general duties medical officers (GDMOs) must be able to provide medical care in a range of austere environments, including humanitarian relief and conflict zones. New clinicians complete their basic military training before completing the PGMNO course and the Diploma in the Medical Care of Catastrophes. This programme ensures that GDMOs and military nurse practitioners gain a wide knowledge of the latest military and humanitarian medicine. The current era will require clinicians who are competent generalists, who can perform in small teams in dispersed locations. This article summarises the development of the British Army's PGMNO course and the evolution of its syllabus as part of the Humanitarian and Disaster Relief Operations special issue of BMJ Military Health.

The consequences of hyperphagia in people with Prader-Willi Syndrome: A systematic review of studies of morbidity and mortality

Prader-Willi Syndrome (PWS) is a multi-system genetically determined neurodevelopmental disorder and the commonest cause of syndromal obesity. The development of hyperphagia in early childhood is part of the phenotype arising as a result of an impaired neural response to food intake and the inability to regulate food intake in line with energy needs. Severe obesity develops if access to food is not controlled. In this review we evaluate the evidence for increased morbidity and mortality in PWS in order to establish the extent to which it is directly related to the obesity; a consequence of the eating behaviour itself independent of obesity; or associated with other characteristics of the syndrome. Medline, Cochrane, PsychINFO, CINAHL, Web of Science and Scopus databases were used to systematically identify published material on PWS and hyperphagia and syndrome-related morbidity and mortality. One hundred and ten key papers were selected. Data on 500 people with PWS indicated that the average age of death was 21 years and obesity was, as expected, a significant factor. However, the behaviour of hyperphagia itself, independent of obesity, was also important, associated with choking, gastric rupture, and/or respiratory illness. Other syndrome-related factors increased the risk for, and seriousness of, co-morbid illness or accidents. We conclude that improving life-expectancy largely depends on managing the immediate non-obesity and obesity-related consequences of the hyperphagia, through improved support. The development of new treatments that significantly reduce the drive to eat are likely to decrease morbidity and mortality improving quality of life and life expectancy.

ECSIT is a critical limiting factor for cardiac function

Evolutionarily conserved signaling intermediate in Toll pathways (ECSIT) is a protein with roles in early development, activation of the transcription factor NF-κB, and production of mitochondrial reactive oxygen species (mROS) that facilitates clearance of intracellular bacteria like Salmonella. ECSIT is also an important assembly factor for mitochondrial complex I. Unlike the murine form of Ecsit (mEcsit), we demonstrate here that human ECSIT (hECSIT) is highly labile. To explore whether the instability of hECSIT affects functions previously ascribed to its murine counterpart, we created a potentially novel transgenic mouse in which the murine Ecsit gene is replaced by the human ECSIT gene. The humanized mouse has low levels of hECSIT protein, in keeping with its intrinsic instability. Whereas low-level expression of hECSIT was capable of fully compensating for mEcsit in its roles in early development and activation of the NF-κB pathway, macrophages from humanized mice showed impaired clearance of Salmonella that was associated with reduced production of mROS. Notably, severe cardiac hypertrophy was manifested in aging humanized mice, leading to premature death. The cellular and molecular basis of this phenotype was delineated by showing that low levels of human ECSIT protein led to a marked reduction in assembly and activity of mitochondrial complex I with impaired oxidative phosphorylation and reduced production of ATP. Cardiac tissue from humanized hECSIT mice also showed reduced mitochondrial fusion and more fission but impaired clearance of fragmented mitochondria. A cardiomyocyte-intrinsic role for Ecsit in mitochondrial function and cardioprotection is also demonstrated. We also show that cardiac fibrosis and damage in humans correlated with low expression of human ECSIT. In summary, our findings identify a role for ECSIT in cardioprotection, while generating a valuable experimental model to study mitochondrial dysfunction and cardiac pathophysiology.

Canadian university students' perceptions of COVID-19 severity, susceptibility, and health behaviours during the early pandemic period

Objectives

We surveyed university students to assess their demographic factors, perceived severity, personal susceptibility, and the adoption of health behaviours in relation to COVID-19.

Study design

Ethics approval was obtained from the University of Toronto’s Research Ethics Board (#39169). Responses were collected between March 20 and April 17, 2020, capturing the first month of government-mandated social distancing in Ontario, Canada.

Methods

We distributed the online survey to the University of Toronto student population, yielding a total convenience sample of 592 participants. We summarised the results and conducted Mann-Whitney U and Kruskal-Wallis tests to explore relationships between demographic data and perceived severity of COVID-19. Pearson’s Chi-square tests were used to explore the relationship between demographic variables and perceived susceptibility, with phi being used to explore the strength of the association. A value of p ​< ​0.05 was used to determine significance.

Results

The majority of participants (60.1%) judged COVID-19 to be Very Severe; there was a significant relationship between being female and the adoption of new health behaviours. 57.4% indicated they felt susceptible to COVID-19, while 40.9% did not. Feeling susceptible was associated with studying a healthcare field or being personally affected by COVID-19. Individuals who stated they were not susceptible to COVID-19 declared mitigating factors such as new health behaviours to be a major driver in their perception.

Conclusion

University students believe COVID-19 is a severe disease and have adopted new and increased health behaviours to mitigate the spread. While this study demonstrates differing health behaviour adoption rates based upon demographic factors, overall this research finds young adults supportive and accepting of government policy as a protective and susceptibility-mitigating measure.

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The majority of participants judged COVID-19 to be very severe.

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Females more likely than other genders to adopt new health behaviours.

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Perceptions of personal susceptibility to COVID-19 varied.

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New health behaviours named as key mitigating factor for judged susceptibility.

[Recommendations for Performing Bronchoscopy in Times of the COVID-19 Pandemic - Update 12/2020]

Die Pandemie ausgelöst durch SARS-CoV-19 geht weltweit unverändert mit einer bedeutsamen Morbidität und Mortalität einher, sodass Schutzmaßnahmen zur Verhinderung der Transmission des Virus weiterhin notwendig sind. Mitarbeiter im Gesundheitswesen sind einem höheren Risiko ausgesetzt, und dies gilt insbesondere im Rahmen sog. Aerosol-generierender Verfahren wie der Bronchoskopie. Seit der Veröffentlichung konsentierter Empfehlungen zur Durchführung einer Bronchoskopie unter diesen Bedingungen vor mehr als einem halben Jahr hat sich die Gefahrenlage nicht wesentlich verändert, aber aufgrund des erheblichen Erkenntnisgewinns in der Zwischenzeit war ein Update der Empfehlungen notwendig. Die erneuerten Empfehlungen umfassen u. a. die Verminderung der Aerosolentstehung, den persönlichen Schutz der beteiligten Personen sowie Maßnahmen zur besseren Organisation der Abläufe in der Endoskopie, um eine sichere Durchführung auch in Zeiten von COVID-19 zu gewährleisten.

Peptide-conjugated oligonucleotides evoke long-lasting myotonic dystrophy correction in patient-derived cells and mice

Antisense oligonucleotides (ASOs) targeting pathologic RNAs have shown promising therapeutic corrections for many genetic diseases including myotonic dystrophy (DM1). Thus, ASO strategies for DM1 can abolish the toxic RNA gain-of-function mechanism caused by nucleus-retained mutant DMPK (DM1 protein kinase) transcripts containing CUG expansions (CUGexps). However, systemic use of ASOs for this muscular disease remains challenging due to poor drug distribution to skeletal muscle. To overcome this limitation, we test an arginine-rich Pip6a cell-penetrating peptide and show that Pip6a-conjugated morpholino phosphorodiamidate oligomer (PMO) dramatically enhanced ASO delivery into striated muscles of DM1 mice following systemic administration in comparison with unconjugated PMO and other ASO strategies. Thus, low-dose treatment with Pip6a-PMO-CAG targeting pathologic expansions is sufficient to reverse both splicing defects and myotonia in DM1 mice and normalizes the overall disease transcriptome. Moreover, treated DM1 patient–derived muscle cells showed that Pip6a-PMO-CAG specifically targets mutant CUGexp-DMPK transcripts to abrogate the detrimental sequestration of MBNL1 splicing factor by nuclear RNA foci and consequently MBNL1 functional loss, responsible for splicing defects and muscle dysfunction. Our results demonstrate that Pip6a-PMO-CAG induces long-lasting correction with high efficacy of DM1-associated phenotypes at both molecular and functional levels, and strongly support the use of advanced peptide conjugates for systemic corrective therapy in DM1.

[Recommendations for Performing Bronchoscopy in Times of the COVID-19 Pandemic]

COVID-19, caused by coronavirus SARS-CoV-2 is a new and ongoing infectious disease affecting healthcare systems worldwide. Healthcare worker are at high risk for COIVD-19 and many have been infected or even died in countries severely affected by COVID-19 like China or Italy. Bronchoscopy causes cough and aerosol production and has to be considered a significant risk for the staff to get infected. Particular recommendations should guide to prevent spreading COVID-19 and to protect healthcare worker when performing a bronchoscopy.

Examining the effects of computerised cognitive training on levels of executive function in adults with Down syndrome

BACKGROUND

Individuals with Down syndrome (DS) are at much greater risk of developing Alzheimer's disease, and one of the early clinical symptoms of Alzheimer's disease is executive dysfunction. In the general population, cognitive training has shown some promising results in relation to maintaining or improving cognitive processes. There is currently a gap in the literature in relation to cognitive training for adults with DS.

METHODS

A quasi-experimental mixed factorial design with partial crossover was used involving an 8-week intervention period using a brain training programme. Participants were matched on age and then randomly assigned to either the intervention group or the delayed intervention group. Forty adults with DS, aged between 30 and 49 and with a mild or moderate level of intellectual disability, participated in the study. All participants completed baseline measures of executive function, using both neuropsychological assessments and an informant-rated measure of behavioural executive function. The intervention group first completed the training and then the delayed intervention group. Executive function assessments were repeated for both groups following the training.

RESULTS

The study aimed to examine whether a cognitive training programme could have an effect on levels of executive function. While conclusions are limited owing to small sample size, improvement was seen in neuropsychological assessments of executive function following cognitive training. Positive effects reflected in everyday behaviours were not as promising.

CONCLUSIONS

This study showed that, while it has not been previously an area of focus, individuals with DS can complete a computerised cognitive training programme. Furthermore, the results were promising with significant improvements found in neuropsychological assessments of executive function. These findings need further investigation with a larger sample size and would benefit from the use of a brain imaging component to strengthen the findings.

Ice algal bloom development on the surface of the Greenland Ice Sheet

It is fundamental to understand the development of Zygnematophycean (Streptophyte) micro-algal blooms within Greenland Ice Sheet (GrIS) supraglacial environments, given their potential to significantly impact both physical (melt) and chemical (carbon and nutrient cycling) surface characteristics. Here, we report on a space-for-time assessment of a GrIS ice algal bloom, achieved by sampling an ∼85 km transect spanning the south-western GrIS bare ice zone during the 2016 ablation season. Cell abundances ranged from 0 to 1.6 × 104 cells ml-1, with algal biomass demonstrated to increase in surface ice with time since snow line retreat (R2 = 0.73, P < 0.05). A suite of light harvesting and photo-protective pigments were quantified across transects (chlorophylls, carotenoids and phenols) and shown to increase in concert with algal biomass. Ice algal communities drove net autotrophy of surface ice, with maximal rates of net production averaging 0.52 ± 0.04 mg C l-1 d-1, and a total accumulation of 1.306 Gg C (15.82 ± 8.14 kg C km-2) predicted for the 2016 ablation season across an 8.24 × 104 km2 region of the GrIS. By advancing our understanding of ice algal bloom development, this study marks an important step toward projecting bloom occurrence and impacts into the future.

Pathoproteomic profiling of the skeletal muscle matrisome in dystrophinopathy associated myofibrosis

The gradual accumulation of collagen and associated proteins of the extracellular matrix is a crucial myopathological parameter of many neuromuscular disorders. Progressive tissue damage and fibrosis play a key pathobiochemical role in the dysregulation of contractile functions and often correlates with poor motor outcome in muscular dystrophies. Following a brief introduction into the role of the extracellular matrix in skeletal muscles, we review here the proteomic profiling of myofibrosis and its intrinsic role in X-linked muscular dystrophy. Although Duchenne muscular dystrophy is primarily a disease of the membrane cytoskeleton, one of its most striking histopathological features is a hyperactive connective tissue and tissue scarring. We outline the identification of novel factors involved in the modulation of the extracellular matrix in muscular dystrophy, such as matricellular proteins. The establishment of novel proteomic markers will be helpful in improving the diagnosis, prognosis, and therapy monitoring in relation to fibrotic substitution of contractile tissue. In the future, the prevention of fibrosis will be crucial for providing optimum conditions to apply novel pharmacological treatments, as well as establish cell-based approaches or gene therapeutic interventions. The elimination of secondary abnormalities in the matrisome promises to reduce tissue scarring and the loss of skeletal muscle elasticity.

Comparative Label-Free Mass Spectrometric Analysis of Mildly versus Severely Affected mdx Mouse Skeletal Muscles Identifies Annexin, Lamin, and Vimentin as Universal Dystrophic Markers

The primary deficiency in the membrane cytoskeletal protein dystrophin results in complex changes in dystrophic muscles. In order to compare the degree of secondary alterations in differently affected subtypes of skeletal muscles, we have conducted a global analysis of proteome-wide changes in various dystrophin-deficient muscles. In contrast to the highly degenerative mdx diaphragm muscle, which showed considerable alterations in 35 distinct proteins, the spectrum of mildly to moderately dystrophic skeletal muscles, including interosseus, flexor digitorum brevis, soleus, and extensor digitorum longus muscle, exhibited a smaller number of changed proteins. Compensatory mechanisms and/or cellular variances may be responsible for differing secondary changes in individual mdx muscles. Label-free mass spectrometry established altered expression levels for diaphragm proteins associated with contraction, energy metabolism, the cytoskeleton, the extracellular matrix and the cellular stress response. Comparative immunoblotting verified the differences in the degree of secondary changes in dystrophin-deficient muscles and showed that the up-regulation of molecular chaperones, the compensatory increase in proteins of the intermediate filaments, the fibrosis-related increase in collagen levels and the pathophysiological decrease in calcium binding proteins is more pronounced in mdx diaphragm as compared to the less severely affected mdx leg muscles. Annexin, lamin, and vimentin were identified as universal dystrophic markers.

[Incidental bronchoscopic findings]

Inflexible and flexible bronchoscopy represents a standard diagnostic procedure in pneumology. Besides lung carcinomas, which is the most frequent indication for diagnostic bronchoscopy, a plethora of clinical symptoms such as chronic persistent cough, hoarseness, unexplained dyspnea, hemoptysis, and suspicious findings on auscultation require further endoscopic evaluation. Moreover, bronchoscopy plays a central role in the diagnostic work-up of interstitial lung diseases and persistent lung infiltrates, in particular those of infectious origin (e.g., fungal, viral, tuberculous, and Pneumocystis jiroveci infections). In addition, diagnostic bronchoscopy has more recently been complemented by endobronchial ultrasound (EBUS). EBUS is predominantly employed for the accurate diagnosis and mediastinal staging of lung carcinomas, and the assessment of lympadenopathy-associated diseases such as sarcoidosis.Since endoscopic evaluation is typically preceded by computed tomography (CT) of the chest, genuine incidental findings occur relatively seldom and usually account for pathological findings that have been missed on conventional imaging approaches. For instance, characteristic incidental findings include benign and malignant tumors in the area of the endoscopic access and central airways, anatomical variations and (vascular) malformations, tracheal and bronchial airway alterations, and aspirated objects. This review focuses on bronchoscopic findings that have either been completely missed by conventional imaging or differently interpreted due to its radiologic morphology.

Label-free mass spectrometric analysis of the mdx-4cv diaphragm identifies the matricellular protein periostin as a potential factor involved in dystrophinopathy-related fibrosis

Proteomic profiling plays a decisive role in the identification of novel biomarkers of muscular dystrophy and the elucidation of new pathobiochemical mechanisms that underlie progressive muscle wasting. Building on the findings of recent comparative analyses of tissue samples and body fluids from dystrophic animals and patients afflicted with Duchenne muscular dystrophy, we have used here label-free MS to study the severely dystrophic diaphragm from the not extensively characterized mdx-4cv mouse. This animal model of progressive muscle wasting exhibits less dystrophin-positive revertant fibers than the conventional mdx mouse, making it ideal for the future monitoring of experimental therapies. The pathoproteomic signature of the mdx-4cv diaphragm included a significant increase in the fibrosis marker collagen and related extracellular matrix proteins (asporin, decorin, dermatopontin, prolargin) and cytoskeletal proteins (desmin, filamin, obscurin, plectin, spectrin, tubulin, vimentin, vinculin), as well as decreases in proteins of ion homeostasis (parvalbumin) and the contractile apparatus (myosin-binding protein). Importantly, one of the most substantially increased proteins was identified as periostin, a matricellular component and apparent marker of fibrosis and tissue damage. Immunoblotting confirmed a considerable increase of periostin in the dystrophin-deficient diaphragm from both mdx and mdx-4cv mice, suggesting an involvement of this matricellular protein in dystrophinopathy-related fibrosis.

Proteomics of the dystrophin-glycoprotein complex and dystrophinopathy

The largest human gene is represented by the X-chromosomal dystrophin gene of 2.4 million bases, which encodes for the membrane cytoskeletal protein dystrophin. The dystrophin isoform Dp427 has a subsarcolemmal location and forms a supramolecular membrane assembly with a variety of glycoproteins. In healthy muscle fibres, dystrophin acts as an actin-binding protein that links the cytoskeleton via the α/β-dystroglycan complex to the extracellular matrix protein laminin. This trans-sarcolemmal complex is believed to stabilize the muscle surface and thus prevents membrane rupturing during excitation-contraction-relaxation cycles. In the highly progressive muscle wasting disease Duchenne muscular dystrophy, the primary deficiency in dystrophin causes a drastic reduction in dystrophin-associated glycoproteins, which renders muscle fibres more susceptible to necrosis. Following the biochemical and cell biological characterization of the dystrophin-glycoprotein complex, several mass spectrometry-based proteomic studies have investigated global changes in dystrophin-deficient muscle tissues. This review briefly outlines the basic domain structure of Dp427 and the composition of the dystrophin-associated glycoprotein complex from skeletal muscle. A detailed discussion of recent proteomic analyses of the purified dystrophin-glycoprotein complex is included, as well as a summary of mass spectrometric surveys of dystrophic specimens. The study of these new areas of muscle proteomics tends to improve our understanding of the normal function of dystrophin in contractile fibres and better define the molecular mechanism of X-linked muscular dystrophy.

New pathobiochemical insights into dystrophinopathy from the proteomics of senescent mdx mouse muscle

Primary abnormalities in the dystrophin gene cause X-linked muscular dystrophy, a highly progressive muscle wasting disorder of childhood. A spontaneous animal model of Duchenne muscular dystrophy is the mdx mouse, which presents a highly interesting phenotype that exhibits considerable variations in the degree of fiber degeneration in different subtypes of muscles. The idea that aging exacerbates the dystrophic mdx phenotype, as previously indicated by a large number of biochemical and cell biological studies, was clearly confirmed by comparative muscle proteomics. Here we outline recent findings of age-dependent changes in the dystrophin-deficient muscle proteome and contrast these results with the previously established proteomic profile of sarcopenic muscle. Besides comparable perturbations of various biochemical functions, especially striking are similarities in the cellular stress response associated with a drastic up-regulation of small αB-crystallin-like heat shock proteins. Hence, the comparison of large-scale proteomic data sets of natural muscle aging with dystrophic sarcopenia promises to shed light on the differential effect of sarcopenia of old age vs. senescent abnormalities on a mutant dystrophic background.

Mass Spectrometry-Based Identification of Muscle-Associated and Muscle-Derived Proteomic Biomarkers of Dystrophinopathies

The optimization of large-scale screening procedures of pathological specimens by genomic, proteomic and metabolic methods has drastically increased the bioanalytical capability for swiftly identifying novel biomarkers of inherited disorders, such as neuromuscular diseases. X-linked muscular dystrophy represents the most frequently inherited muscle disease and is characterized by primary abnormalities in the membrane cytoskeletal protein dystrophin. Mass spectrometry-based proteomics has been widely employed for the systematic analysis of dystrophin-deficient muscle tissues, using patient samples and animal models of dystrophinopathy. Both, gel-based methods and label-free mass spectrometric techniques have been applied in comparative analyses and established a large number of altered proteins that are associated with muscle contraction, energy metabolism, ion homeostasis, cellular signaling, the cytoskeleton, the extracellular matrix and the cellular stress response. Although these new indicators of muscular dystrophy have increased our general understanding of the molecular pathogenesis of dystrophinopathy, their application as new diagnostic or prognostic biomarkers would require the undesirable usage of invasive methodology. Hence, to reduce the need for diagnostic muscle biopsy procedures, more recent efforts have focused on the proteomic screening of suitable body fluids, such as plasma, serum or urine, for the identification of changed concentration levels of muscle-derived peptides, protein fragments or intact proteins. The occurrence of muscular dystrophy-related protein species in biofluids will be extremely helpful for the future development of cost-effective and non-invasive diagnostic procedures. Novel biomarker signatures of dystrophinopathies will be indispensible for the swift evaluation of innovative therapeutic approaches, such as exon skipping, codon-read-through or stem cell therapy.

Correlation between serum reactivity to Demodex-associated Bacillus oleronius proteins, and altered sebum levels and Demodex populations in erythematotelangiectatic rosacea patients

Rosacea is a chronic inflammatory condition that affects the skin of the face and the eyes. The aetiology of rosacea is not clearly established but increasing evidence suggests a potential role for bacteria in the induction of the condition. A role for Bacillus oleronius, originally isolated from within a Demodex folliculorum mite, in the aetiology of the condition has been suggested. The aim of the study was to determine whether a correlation existed between the level of sebum and the density of D. folliculorum in the skin of erythematotelangiectatic rosacea patients, and the reactivity of these patients' sera to proteins of B. oleronius. Serum reactivity to the 62 and 83 kDa B. oleronius proteins was found in 82.6 % (62/75) of the rosacea patients and in 26.9 % (14/52) of controls (P = 0.0016). In the group of rosacea patients whose sera reacted to B. oleronius proteins, the level of sebum was statistically lower than in controls (P = 0.01). The density of D. folliculorum on the face of Bacillus positive rosacea patients was statistically higher than controls (P = 0.0001). Rosacea patients demonstrated increased Demodex populations on their faces and reduced sebum levels. Their sera also showed reactivity to B. oleronius proteins, suggesting a potential role for this bacterium in the aetiology of rosacea.