Stress among Pediatric Occupational Therapists: A Study of Prevalence, Work and Demographic Factors

This study aimed to evaluate the self-reported stress levels of pediatric occupational therapists, examine specific work factors and determine if demographic factors predict occupational stress. A cross-sectional survey design study, using voluntary response sampling, was conducted. The survey included demographics, the Workplace Stress Scale, and the Stress Index. The sample included 289 pediatric occupational therapists. Using descriptive analysis, a one-sample t-test, and multiple linear regressions, results indicated that pediatric occupational therapists had significantly higher stress levels than the validating sample of the Workplace Stress Scale. Self-reported work factors included too much work to do in a limited time and lack of time to plan or evaluate treatments. No demographic factors predicted work stress, while several work factors did. Occupational stress exists in pediatric occupational therapy work settings, especially in settings where high productivity is self-reported.

Missed Opportunities to Ease Suffering: An Explanatory Model of Occupational Therapy Utilization in End-of-Life Care

Background: With disease progression, a terminally ill person may experience loss of physical and cognitive skills required to perform everyday activities. Such functional loss can erode autonomy and cause existential suffering. Supported engagement in everyday activities may help terminally ill people stay involved in living and cope with dying. Occupational therapy enables people to engage in valued activities at the end of life, yet remains under-utilized. Objectives: To address the perceived under-utilization of end-of-life care occupational therapy, the authors investigated how utilization of occupational therapy in end-of-life care is determined from the perspective of decision-makers and occupational therapists and then developed a model of the process. Methods: Using a grounded theory method, authors conducted two semi-structured interviews with 20 decision-makers and 21 occupational therapists. Theoretical sampling followed by paradigm analysis, yielded a data-grounded model. Results: The authors developed The Model of Occupational Therapy Utilization in End-of-Life Care. Service utilization was primarily contingent upon the decision-makers' awareness of occupational therapy's role in end-of-life care and further influenced by place of care cost constraints and participants' ability to adjust focus of the occupational therapy to accommodate the patient's dying process. Conclusion: Limited awareness of occupational therapy's role in end-of-life care warrants research on whether modification of model constructs may increase awareness and utilization. Education is indicated to teach providers about suffering due to functional loss and how to adjust focus of occupational therapy to sustain occupational participation through decline, across different care settings, and along a range between rehabilitation-focused to participation-focused outcomes.

"You've Got to Do Something": Developing Occupational Therapists' Role in End-of-Life Care

Occupational therapists support the occupational participation of people who are dying yet remain underutilized in end-of-life care. The purpose of this article was to explore how occupational therapists develop their role in end-of-life care to provide strategies to address underutilization. Using a grounded-theory method, semi-structured interviews were conducted with 21 occupational therapists. Three themes emerged which demonstrate participants' role development process. Participants' experiences with dying (Close Experience of Loss) often instilled the importance of end-of-life care. Led by these convictions (Willing to Do It), participants developed skills for end-of-life care. Reflecting on their experiences and treatment outcomes (Making a Difference), participants self-validated their role. The Model of Occupational Therapists' Role Development in End-of-Life Care captured this process. Personal experiences and critical self-reflection may provide an adaptive means to drive role development and appropriately increase end-of-life care occupational therapy utilization.

Pediatric Occupational Therapists and Occupational Stress: A Scoping Review

The purpose of this scoping review was to provide further insight into the stress and the stressors experienced by pediatric occupational therapists in the work environment. Using the Arksey and O'Malley framework, the search was conducted in eight databases, nine electronic journals, and eight gray literature sources to identify articles related to stress and stressors of pediatric occupational therapists. Review selection and characterization were performed by two independent reviewers. Twelve articles published from 2011 to 2020 were identified and varied in terms of purpose, population, and results although the articles all shared similar methodologies and outcome measures. Only 25% of the articles (3/12) addressed pediatric occupational therapy stress and stressors directly while the remaining addressed occupational stress, but with varying levels of attention to pediatric occupational therapists. Stress and stressors experienced by pediatric occupational therapists have been studied to a limited extent. Occupational stress is associated with increased burnout, decreased health, and decreased job satisfaction and performance. Several knowledge gaps have been identified, as well as priorities for future research into pediatric occupational therapists and occupational stress.

Promoting Self-Management of Breast Cancer-Related Lymphedema Through the Remotivation Process

Date Presented 04/01/2022

Lymphedema affects a significant number of women with breast cancer, and self-management programs (SMPs) are important in the long-term management of this chronic condition. This quasi-experimental study explored the effect of the remotivation process on the motivation of 11 women with lymphedema to perform an SMP. Results showed improved motivation and increased performance of the SMP. This study provides evidence that the remotivation process can facilitate motivation and promote SMP performance.

Primary Author and Speaker: Kaye Rubio

Contributing Authors: Patricia Bowyer, Sherry Hite, Vidya Pingale, Christine Raber, Gayle Hersch, Wyona Freysteinson

The Remotivation Process as a Telehealth OT Program to Promote Self-Management in Women With Breast Cancer–Related Lymphedema

Date Presented 04/02/2022

Lymphedema affects 65% of women with breast cancer. Self-management programs (SMPs) are used to manage lymphedema. The study explored the effect of the Remotivation Process on the motivation of 12 women to perform an SMP every day. It was provided through a telehealth platform. Analysis showed significant change in motivation and outcome measures. This study found that the Remotivation Process is a potentially useful OT intervention to address the motivational needs of women with lymphedema.

Primary Author and Speaker: Kaye Rubio

Contributing Authors: Patricia Bowyer, Vidya Pingale, Sherry Hite, Gayle Hersch, Christine Raber, Wyona Freysteinson

OT in Acute Care: Predictors of Occupational Competence and Hospital Readmissions

Date Presented 04/6/21

This study explores predictors of occupational competence and hospital readmission for clients with chronic conditions in acute care. Self-care function (β = 0.43, p = .01) and environmental impact (β = –.38, p = .01) significantly predict occupational competence. Functional cognition (OR = 2.19, p = .04) and occupational competence (OR = 0.81, p = .02) significantly predict hospital readmission. OTs should consider standardized measures of these predictors to facilitate successful discharge home.

Primary Author and Speaker: Melanie Tkach

Additional Authors and Speakers: John R. Patro, Emily Gavin

The Remotivation Process as a Telehealth OT Program to Promote Self-Management in Women With Breast-Cancer-Related Lymphedema

Date Presented Accepted for AOTA INSPIRE 2021 but unable to be presented due to online event limitations.

Lymphedema affects 65% of women with breast cancer. Self-management programs (SMPs) are used to manage lymphedema. The study explored the effect of the Remotivation Process on the motivation of 12 women to perform a SMP every day. It was provided through a telehealth platform. Analysis showed significant changes in motivation and outcome measures. This study found that the Remotivation Process is a potentially useful OT intervention to address the motivational needs of women with lymphedema.

Primary Author and Speaker: Kaye Rubio

Contributing Authors: Patricia Bowyer, Sherry Hite, Vidya Pingale, Wyona Freysteinson, Gayle Hersch, and Christine Raber

Occupational therapy, cancer, and occupation-centred practice: impact of training in the model of human occupation

INTRODUCTION

This study examined the influence of training in an occupation-centred model on the practice of occupational therapists working in a cancer hospital. There is an increased need for occupation-based rehabilitation services for individuals with and surviving cancer. Incorporating an occupation-centred model into practice has unique challenges for occupational therapists working in oncology settings. Utilizing an occupation-centred model of practice may influence the therapeutic reasoning of occupational therapists.

METHODS

A generic qualitative inquiry (Patton, 2015) was used to examine therapeutic reasoning as related to post-professional training in a specific occupation-centred model, the Model of Human Occupation (MOHO). Initially, ten occupational therapists with various levels of experience, working across populations in a large cancer centre completed a training session about the MOHO. This was followed by participation in monthly focus groups with an emphasis on the use of MOHO in daily practice (Taylor, 2017). Focus group sessions were video recorded and transcribed. The transcripts were then analysed using open coding and theme generation (Patton, 2015).

RESULTS

Three major themes were extracted from the data during the thematic analysis: understanding and using MOHO language; challenges in incorporating a conceptual model of occupation-centred practice in an oncology setting; and therapeutic reasoning implications. Patterns in the themes indicated a progression from learning the model, to applying the model, to reflection on practice.

CONCLUSION

Post-professional training in an occupation-based model influenced the therapeutic reasoning and practice of occupational therapists in an oncology setting.

Detection of Pneumocystis jirovecii by quantitative real-time PCR in oral rinses from Pneumocystis pneumonia asymptomatic human immunodeficiency virus patients

Pneumocystis pneumonia (PCP) is a potentially life-threatening fungal infection usually seen in immunocompromised patients. Pneumocystis jirovecii can be easily detected from oral rinse samples in HIV patients with suspected PCP. In this study, a quantitative real-time PCR assay was used to establish the frequency of detection of P. jirovecii in oral rinses from HIV patients without respiratory symptoms or suspicion of PCP. Two saline oral rinses were collected from 100 ambulant HIV patients and from 60 COPD patients (comparator group). Four HIV patients were positive for P. jirovecii. In three patients, the first sample was positive and in one the second one was positive. One of these patients was on PCP prophylaxis and had a CD4⁺ count of 76 cells/mm³. The mean CD4⁺ count for all patients was 527 cells/mm³. All qRT-PCR test results for the COPD patients were negative. No patient developed PCP at six months follow-up. The qRT-PCR assay can be used to detect P. jirovecii DNA in oral rinse samples from HIV patients without evident clinical symptoms, however the oral carriage of this fungus was rare in our cohort of patients. In conclusion, although rare, a positive oral rinse P. jirovecii result may reflect colonisation, in particular in patients with HIV. This needs to be kept in mind when using oral rinses and qRT-PCR in the diagnosis of P. jirovecii infection.

Long-Term Impact of Model of Human Occupation Training on Therapeutic Reasoning

This general qualitative study explores occupational therapists' perspectives related to the long-term impact of Model of Human Occupation (MOHO) training on therapeutic reasoning in practice. MOHO is a widely used, occupation-focused theory that promotes participation and engagement in meaningful activities for occupational adaptation. One-on-one, semi-structured interviews were conducted with six occupational therapists at a cancer rehabilitation center who previously underwent systematic MOHO training. Therapists acquired or expanded MOHO knowledge as a result of training and retained that knowledge 9 months later. They also implemented training-related practice changes including the provision of more holistic, client-centered occupational therapy services and systematic use of the MOHO to reason in practice 9 months later. Specific results varied based on experience with the MOHO prior to study-related training. MOHO training promotes knowledge acquisition and positive practice changes long-term for occupational therapists in cancer rehabilitation. Similar trainings would meet therapists' desire to learn more about theory-driven practice and improve their clinical reasoning skills. Future research should explore how results transfer to other facilities and how therapeutic reasoning with the MOHO impacts quality of care.

Treatment fidelity in Model of Human Occupation research

Introduction

Treatment fidelity is an important consideration in occupational therapy efficacy research. It involves methodological strategies that enhance quantitative rigor and improves confidence in research outcomes. This study examines treatment fidelity in Model of Human Occupation efficacy literature because it is a widely used, occupation-focused theory with a substantial evidence base.

Method

Relevant articles ( n = 17) were coded for treatment fidelity with the Treatment Fidelity Measure. Percentages of articles reporting treatment fidelity strategies and mean adherence to fidelity strategies were calculated. One-way analysis of variance was used to examine fidelity over time.

Results

Only one study reported provider training strategies and measured nonspecific treatment effects. Overall mean adherence to treatment fidelity strategies for Model of Human Occupation research was 0.57; one study demonstrated high fidelity with a score of ≥0.80. Model of Human Occupation efficacy literature trends toward higher levels of treatment fidelity over time.

Conclusion

Model of Human Occupation research demonstrates a moderate level of treatment fidelity overall; it has stronger treatment fidelity from 2001 to the present. As the model progresses toward more outcomes studies, Model of Human Occupation scholars should report provider training and strategies that monitor treatment delivery to improve the quality and applicability of research outcomes.

A Study of the Amputee Experience of Viewing Self in the Mirror

Purpose

To describe the trajectory of viewing self in a mirror after an ampu-tation and participants’ perceptions of what health care professionals should know about mirrors.

Design

Hermeneutic phenomenology

Methods

Focus groups were conducted to collect the research data.

Findings

The mirror experience had three key moments: decision, seeing, and consent. The trajectory of viewing self in a mirror had four key themes: mirror shock, mirror anguish, recognizing self, and acceptance: a new normal. Participants’ recommendations for introducing the mirror after an amputation and using a mirror to avoid skin breakdown and infection, and correct gait and balance are described.

Conclusions

This study provides a unique viewpoint into the world of those who have suffered amputation of a limb.

Clinical Relevance

Rehabilitation nurses and other health care professionals are encouraged through these participants to consider the effect and value of mirrors when caring for those who have had an amputation.

Genetic susceptibility to severe asthma with fungal sensitization

Severe asthma is problematic and its pathogenesis poorly understood. Fungal sensitization is common, and many patients with severe asthma with fungal sensitization (SAFS), used to denote this subgroup of asthma, respond to antifungal therapy. We have investigated 325 haplotype-tagging SNPs in 22 candidate genes previously associated with aspergillosis in patients with SAFS, with comparisons in atopic asthmatics and healthy control patients, of whom 47 SAFS, 279 healthy and 152 atopic asthmatic subjects were genotyped successfully. Significant associations with SAFS compared with atopic asthma included Toll-like receptor 3 (TLR3) (p = .009), TLR9 (p = .025), C-type lectin domain family seven member A (dectin-1) (p = .043), interleukin-10 (IL-10) (p = .0010), mannose-binding lectin (MBL2) (p = .007), CC-chemokine ligand 2 (CCL2) (2 SNPs, p = .025 and .041), CCL17 (p = .002), plasminogen (p = .049) and adenosine A2a receptor (p = .024). These associations differ from those found in ABPA in asthma, indicative of contrasting disease processes. Additional and broader genetic association studies in SAFS, combined with experimental work, are likely to contribute to our understanding of different phenotypes of problematic asthma.

Determining the Internal Validity of the Inventory of Reading Occupations: An Assessment Tool of Children's Reading Participation

The Inventory of Reading Occupations (IRO) is an assessment tool of children's reading participation. In this study, we used Rasch methods to determine the internal validity of the IRO. Participants included 192 typical and struggling readers from kindergarten to third grade from five different states in the United States. We analyzed the fit of each of the items in the 17 reading categories, the test items in the three dimensions of reading participation, and the contexts of reading in the IRO. Analysis indicated that the IRO items support the Rasch model of unidimensionality. Analysis also indicated that 1 of the 30 test items can be revised to strengthen test validity. Moreover, the analysis also suggested that the IRO is more useful for first- to third-grade students. This study provides evidence of internal validity of a useful tool to assess children's reading participation.

Aspergillus fumigatus proteases, Asp f 5 and Asp f 13, are essential for airway inflammation and remodelling in a murine inhalation model

BACKGROUND

In susceptible individuals, exposure to Aspergillus fumigatus can lead to the development of atopic lung diseases such as allergic bronchopulmonary aspergillosis (ABPA) and severe asthma with fungal sensitization (SAFS). Protease allergens including Asp f 5 and Asp f 13 from Aspergillus fumigatus are thought to be important for initiation and progression of allergic asthma.

OBJECTIVE

To assess the importance of secreted protease allergens Asp f 5 (matrix metalloprotease) and Asp f 13 (serine protease) in Aspergillus fumigatus-induced inflammation, airway hyperactivity, atopy and airway wall remodelling in a murine model following chronic exposure to secreted allergens.

METHODS

BALB/c mice were repeatedly intranasally dosed over the course of 5 weeks with culture filtrate from wild-type (WT), Asp f 5 null (∆5) or Asp f 13 null (∆13) strains of Aspergillus fumigatus. Airway hyper-reactivity was measured by non-invasive whole-body plethysmography, Th2 response and airway inflammation by ELISA and cell counts, whilst airway remodelling was assessed by histological analysis.

RESULTS

Parent WT and ∆5 culture filtrates showed high protease activity, whilst protease activity in ∆13 culture filtrate was low. Chronic intranasal exposure to the three different filtrates led to comparable airway hyper-reactivity and Th2 response. However, protease allergen deleted strains, in particular ∆13 culture filtrate, induced significantly less airway inflammation and remodelling compared to WT culture filtrate.

CONCLUSION

Aspergillus fumigatus-secreted allergen proteases, Asp f 5 and Asp f 13, are important for recruitment of inflammatory cells and remodelling of the airways in this murine model. However, deletion of a single allergen protease fails to alleviate airway hyper-reactivity and allergic immune response. Targeting protease activity of Aspergillus fumigatus in conditions such as SAFS or ABPA may have beneficial effects in preventing key aspects of airway pathology.

2-hydroxyisocaproic acid is fungicidal for Candida and Aspergillus species

The amino acid derivative 2-hydroxyisocaproic acid (HICA) is a nutritional additive used to increase muscle mass. Low levels can be detected in human plasma as a result of leucine metabolism. It has broad antibacterial activity but its efficacy against pathogenic fungi is not known. The aim was to test the efficacy of HICA against Candida and Aspergillus species. Efficacy of HICA against 19 clinical and reference isolates representing five Candida and three Aspergillus species with variable azole antifungal sensitivity profiles was tested using a microdilution method. The concentrations were 18, 36 and 72 mg ml(-1) . Growth was determined spectrophotometrically for Candida isolates and by visual inspection for Aspergillus isolates, viability was tested by culture and impact on morphology by microscopy. HICA of 72 mg ml(-1) was fungicidal against all Candida and Aspergillus fumigatus and Aspergillus terreus isolates. Lower concentrations were fungistatic. Aspergillus flavus was not inhibited by HICA. HICA inhibited hyphal formation in susceptible Candida albicans and A. fumigatus isolates and affected cell wall integrity. In conclusion, HICA has broad antifungal activity against Candida and Aspergillus at concentrations relevant for topical therapy. As a fungicidal agent with broad-spectrum bactericidal activity, it may be useful in the topical treatment of multispecies superficial infections.

Fermentative 2-carbon metabolism produces carcinogenic levels of acetaldehyde in Candida albicans

Acetaldehyde is a carcinogenic product of alcohol fermentation and metabolism in microbes associated with cancers of the upper digestive tract. In yeast acetaldehyde is a by-product of the pyruvate bypass that converts pyruvate into acetyl-Coenzyme A (CoA) during fermentation.

THE AIMS OF OUR STUDY WERE

(i) to determine the levels of acetaldehyde produced by Candida albicans in the presence of glucose in low oxygen tension in vitro; (ii) to analyse the expression levels of genes involved in the pyruvate-bypass and acetaldehyde production; and (iii) to analyse whether any correlations exist between acetaldehyde levels, alcohol dehydrogenase enzyme activity or expression of the genes involved in the pyruvate-bypass. Candida albicans strains were isolated from patients with oral squamous cell carcinoma (n = 5), autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy (APECED) patients with chronic oral candidosis (n = 5), and control patients (n = 5). The acetaldehyde and ethanol production by these isolates grown under low oxygen tension in the presence of glucose was determined, and the expression of alcohol dehydrogenase (ADH1 and ADH2), pyruvate decarboxylase (PDC11), aldehyde dehydrogenase (ALD6) and acetyl-CoA synthetase (ACS1 and ACS2) and Adh enzyme activity were analysed. The C. albicans isolates produced high levels of acetaldehyde from glucose under low oxygen tension. The acetaldehyde levels did not correlate with the expression of ADH1, ADH2 or PDC11 but correlated with the expression of down-stream genes ALD6 and ACS1. Significant differences in the gene expressions were measured between strains isolated from different patient groups. Under low oxygen tension ALD6 and ACS1, instead of ADH1 or ADH2, appear the most reliable indicators of candidal acetaldehyde production from glucose.

Determining the Clinical Utility of the Short Child Occupational Profile (SCOPE)

Objective:

The purpose of this study was to propose a process for the study of clinical utility and to illustrate its implementation in the development of an assessment.

Method:

A mixed methods approach was used to understand the clinical utility of an assessment in development. An exploratory qualitative/quantitative (QUAL?QUANT) approach was used to identify perspectives of the clinical utility of the assessment. The design placed equal status on the two methods used: focus groups and surveys.

Results:

The proposed process for the study of clinical utility resulted in targeted revisions based upon data obtained from 21 practitioners in three focus groups during a systemised examination of clinical utility.

Conclusion:

A mixed methods process can be used to ensure the clinical utility of assessments during the development process.

Striving for Shared Understandings: Therapists' Perspectives of the Benefits and Dilemmas of Using a Child Self-Assessment

Pediatric client-centered intervention planning is particularly complex because children, parents, and professionals must form a “tridactic” partnership and reach a shared understanding for therapy. Therapists may use child self-reports to facilitate children's involvement in this process. The purpose of this study was to understand how therapists used and interpreted a child self-report to achieve a shared understanding in the context of a tridactic relationship, using the Children's Occupational Self-Assessment (COSA) as an exemplar. Thirty-three pediatric therapists participated in five focus groups and qualitative analysis was conducted in four iterative phases. Therapists' decision to use the COSA led to either “good” responses or unexpected tensions between the therapist's, child's, and parent's perspectives. Therapists used demonstration, negotiation, or reflection to shift beliefs to achieve a shared understanding for therapy. Findings suggest that although therapists valued children's voices, professional knowledge usually took precedence over child and parent self-knowledge during intervention planning.

An improved model of the Aspergillus fumigatus CYP51A protein

Azole resistance is an increasing clinical problem for Aspergillus fumigatus, with the majority of published resistance arising from mutations in the azole target gene CYP51A. Previous structural studies of this protein have suffered from a nonorthologous, low-homology template for homology modeling. Here we present a new model based on the human CYP51A orthologue that provides a higher-quality model for A. fumigatus CYP51A.

How Interdisciplinary Pediatric Practitioners Choose Assessments

Background. The assessment process affects the direction and quality of the services children and youth with disabilities receive. However, little is known about how practitioners choose tools and strategies to assess clients. Purpose. To identify processes practitioners use to gather information and choose methods of assessment in pediatric practice. Methods. Three focus groups were held with teams of interdisciplinary pediatric practitioners. Key themes were identified. Findings. Two primary themes emerged: “Things practitioners want to know” and “Choosing what and how to assess.” Practitioners began the assessment process wanting to gather information about children and their environment. Practitioners then used the initial information to decide what and how to further assess as described by three subthemes: “fitting” the child, balancing formal and informal information, and professional context. Implications. Practitioners generally made individualized assessment choices for each child based on the initial information they gathered and then used a balance of formal and informal assessments. However, they were more likely to formally assess children at the level of body structures and function rather than participation, and continued to rely upon such standardized assessments to meet reimbursement and policy requirements.

Examining Rater Behavior on a Revised Version of the Short Child Occupational Profile (SCOPE)

A previous study of the Short Child Occupational Profile (SCOPE), an assessment of occupational participation, supported the psychometric soundness of the instrument overall, but pointed to some potential problems in practitioners' use of the SCOPE in practice. Specific revisions were made to the SCOPE to address the rating behaviors of leniency/severity, halo effect, and restriction of range. A many-faceted Rasch model analysis was conducted after 39 practitioners working in eight practice sites learned to administer the SCOPE using a variety of methods and rated 168 clients using the SCOPE (version 2.1). Practitioners exhibited three significantly different levels of leniency/severity, 35 practitioners did not exhibit any halo effects, and the top three rating categories were used 91% of the time. Findings suggest that a variety of methods can be used to learn to administer and rate the SCOPE in an appropriate manner to assess the personal and environmental factors affecting the occupational participation of children.

International efforts to disseminate and develop the model of human occupation

This paper documents efforts in Canada, France, Finland, Germany, Hispanoamerica, Israel, Japan, The Netherlands, and Taiwan to disseminate the Model of Human Occupation (MOHO). We aim to characterize the challenges involved, the strategies used, and the impact of these efforts in diverse cultural and social conditions.

Aspergillus flavus: human pathogen, allergen and mycotoxin producer

Aspergillus infections have grown in importance in the last years. However, most of the studies have focused on Aspergillus fumigatus, the most prevalent species in the genus. In certain locales and hospitals, Aspergillus flavus is more common in air than A. fumigatus, for unclear reasons. After A. fumigatus, A. flavus is the second leading cause of invasive aspergillosis and it is the most common cause of superficial infection. Experimental invasive infections in mice show A. flavus to be 100-fold more virulent than A. fumigatus in terms of inoculum required. Particularly common clinical syndromes associated with A. flavus include chronic granulomatous sinusitis, keratitis, cutaneous aspergillosis, wound infections and osteomyelitis following trauma and inoculation. Outbreaks associated with A. flavus appear to be associated with single or closely related strains, in contrast to those associated with A. fumigatus. In addition, A. flavus produces aflatoxins, the most toxic and potent hepatocarcinogenic natural compounds ever characterized. Accurate species identification within Aspergillus flavus complex remains difficult due to overlapping morphological and biochemical characteristics, and much taxonomic and population genetics work is necessary to better understand the species and related species. The flavus complex currently includes 23 species or varieties, including two sexual species, Petromyces alliaceus and P. albertensis. The genome of the highly related Aspergillus oryzae is completed and available; that of A. flavus in the final stages of annotation. Our understanding of A. flavus lags far behind that of A. fumigatus. Studies of the genomics, taxonomy, population genetics, pathogenicity, allergenicity and antifungal susceptibility of A. flavus are all required.

Aspergillus flavus: human pathogen, allergen and mycotoxin producer

Aspergillus infections have grown in importance in the last years. However, most of the studies have focused on Aspergillus fumigatus, the most prevalent species in the genus. In certain locales and hospitals, Aspergillus flavus is more common in air than A. fumigatus, for unclear reasons. After A. fumigatus, A. flavus is the second leading cause of invasive aspergillosis and it is the most common cause of superficial infection. Experimental invasive infections in mice show A. flavus to be 100-fold more virulent than A. fumigatus in terms of inoculum required. Particularly common clinical syndromes associated with A. flavus include chronic granulomatous sinusitis, keratitis, cutaneous aspergillosis, wound infections and osteomyelitis following trauma and inoculation. Outbreaks associated with A. flavus appear to be associated with single or closely related strains, in contrast to those associated with A. fumigatus. In addition, A. flavus produces aflatoxins, the most toxic and potent hepatocarcinogenic natural compounds ever characterized. Accurate species identification within Aspergillus flavus complex remains difficult due to overlapping morphological and biochemical characteristics, and much taxonomic and population genetics work is necessary to better understand the species and related species. The flavus complex currently includes 23 species or varieties, including two sexual species, Petromyces alliaceus and P. albertensis. The genome of the highly related Aspergillus oryzae is completed and available; that of A. flavus in the final stages of annotation. Our understanding of A. flavus lags far behind that of A. fumigatus. Studies of the genomics, taxonomy, population genetics, pathogenicity, allergenicity and antifungal susceptibility of A. flavus are all required.

The link between fungi and severe asthma: a summary of the evidence

There is current evidence to demonstrate a close association between fungal sensitisation and asthma severity. Whether such an association is causal remains to be confirmed, but this is explored by means of a detailed literature review. There is evidence from two randomised controlled trials that, in the example of allergic bronchopulmonary aspergillosis (ABPA), treatment with systemic antifungal therapy can offer a therapeutic benefit to approximately 60% of patients. ABPA is only diagnosed if a combination of clinical and immunological criteria is achieved. It is not known whether such cases are a discrete clinical entity or part of a spectrum of the pulmonary allergic response to fungi or fungal products. This paper describes the epidemiological evidence that associates severity of asthma with fungi and discusses possible pathogenetic mechanisms. Many airborne fungi are involved, including species of Alternaria, Aspergillus, Cladosporium and Penicillium, and exposure may be indoors, outdoors or both. The potential for a therapeutic role of antifungal agents for patients with severe asthma and fungal sensitisation is also explored. Not only are many patients with severe asthma desperately disabled by their disease, but, in the UK alone, asthma accounts for 1,500 deaths per yr. The healthcare costs of these patients are enormous and any treatment option merits close scrutiny. Within this report, the case for the consideration of a new term related to this association is put forward. The current authors propose the term "severe asthma with fungal sensitisation". However, it is recognised that enhanced and precise definition of fungal sensitisation will require improvements in diagnostic testing.

Relative reactivity of Aspergillus allergens used in serological tests

Aspergillus is a common disease-causing agent, both as an allergen causing ABPA and severe asthma with fungal sensitization (SAFS) and as a pathogen causing invasive aspergillosis in immunocompromised individuals and chronic cavitating disease (CCPA) in apparently immune competent individuals. Currently detection of Aspergillus is problematic and some of the most useful tests rely on detection of antibody response to Aspergillus allergens. Here we examine the IgE antibody response to crude and recombinant allergen tests (Asp f 1, Asp f 2, Asp f 4 and Asp f 6) in individuals with allergic conditions ABPA, SAFS and in individuals with CCPA. Additionally we use recently obtained genomic information to examine the possibility of cross reaction to these allergens and show that possible cross reactive epitopes occur in several species of Aspergillus.

Interdisciplinary staff perceptions of an occupational therapy return to work program for people living with AIDS

The purpose of this qualitative study was to identify the perception of interdisciplinary staff members regarding the impact of a model work and independent living oriented program for residents in supportive living facilities. This study used focus groups and individual interviews to collect these perceptions. Staff members identified four areas of impact: utilization of a holistic and process-oriented approach, an ability to identify and work with the strengths of clients, emphasis on the learning of practical skills, and creating an intersection for all aspects of services. These findings point to the fact that staff members found the value that occupational therapy has to offer their overall programming by improving participation of clients with HIV in learning practical skills for use in their daily lives and in developing work related skills.

Ornithine decarboxylase knockout in Tapesia yallundae abolishes infection plaque formation in vitro but does not reduce virulence toward wheat

A knockout strain of Tapesia yallundae lacking the single ornithine decarboxylase (ODC) allele has been created by targeted gene replacement. A central region of the ODC gene was isolated by polymerase chain reaction with degenerate oligonucleotides and used to probe a lambda genomic library. The gene was sequenced, and the encoded ODC protein sequence was shown to be similar to those from other fungi. The functionality of the T. yallundae ODC was confirmed by complementation of an Aspergillus nidulans mutant (puA) strain devoid of ODC activity, restoring growth in the absence of exogenous polyamines. Transformation-mediated gene replacement was used to create strains that were auxotrophic for putrescine and lack ODC coding sequences. ODC knockout strains were unable to differentiate infection structures after in vitro induction and showed an abnormal hyphal branching phenotype. Pathogenicity studies on these mutants showed that, surprisingly, they are not reduced in virulence compared with nondisrupted transformants. This suggests that the strains carrying an ODC disruption can obtain sufficient polyamines from the host plant for normal growth and differentiation and, therefore, that fungal ODC may not be a suitable target for fungicides.

Use of an isocitrate lyase promoter-GFP fusion to monitor carbon metabolism of the plant pathogen Tapesia yallundae during infection of wheat

Abstract Green fluorescent protein (GFP) has been used as a vital marker in a variety of species. Here, we present the use of a GFP-promoter fusion to visualize carbon metabolism in a pathogenic fungus during growth on defined medium and during infection of plants. Isocitrate lyase (ICL), a key enzyme in carbon metabolism, is tightly regulated at the transcriptional level, with high levels of expression during 2-carbon growth and no expression during growth on glucose. A GFP-ICL promoter fusion was used to visualize carbon metabolism in the plant pathogenic fungus Tapesia yallundae during growth in vitro and in the host plant. The ICL promoter from Neurospora crassa retained its native induction and repression characteristics in T. yallundae. Loss of GFP fluorescence from hyphae after repression of the ICL promoter suggested a rapid turnover rate for GFP in T. yallundae. Regulation of this promoter was observed during infection, with expression occurring only on the plant surface, suggesting that 2-carbon metabolism occurs during this phase. These data suggest that GFP is a useful vital marker for the in planta imaging of fungal metabolism.

Ornithine decarboxylase of Stagonospora (Septoria) nodorum is required for virulence toward wheat

A knockout strain of Stagonospora (Septoria) nodorum lacking the single ornithine decarboxylase (ODC) allele has been created by targeted gene replacement. A central region of the S. nodorum ODC gene was isolated by polymerase chain reaction using degenerate oligonucleotides and used to probe a lambda genomic library. The gene was sequenced and the encoded ODC protein sequence was shown to be similar to those from other fungi. The functionality of the S. nodorum ODC was confirmed by complementation of an Aspergillus nidulans mutant (puA) strain devoid of ODC activity, restoring growth in the absence of exogenous polyamines. Sporulation of the transformants was reduced suggesting abberant regulation of the S. nodorum gene in A. nidulans. Transformation-mediated gene replacement was used to create strains which were auxotrophic for putrescine and lack ODC coding sequences. Pathogenicity studies on these mutants showed that they are greatly reduced in virulence compared with non-disrupted transformants. This confirms that the strains carrying an ODC disruption cannot obtain sufficient polyamines from the host plant for normal growth and, thus, that fungal ODC may be a suitable target for chemical intervention.

Characterization of SNP1, a cell wall-degrading trypsin, produced during infection by Stagonospora nodorum

Stagonospora (= Septoria) nodorum when grown in liquid culture with wheat cell walls as the sole carbon and nitrogen source secretes numerous extracellular depolymerases, including a rapidly produced, alkaline, trypsin-like protease (SNP1). The enzyme was purified 417-fold by cation exchange chromatography and has a molecular mass of 25 kDa on sodium dodecyl sulfate gels, pI 8.7, and pH optimum of 8.5. It cleaved peptide bonds on the carboxyl side of lysine or arginine, was strongly inhibited by the trypsin inhibitors aprotinin and leupeptin and weakly by phenylmethylsulfonyl fluoride, and its activity was stimulated by calcium. SNP1 has the characteristic, conserved, fungal, trypsin N terminus. Polymerase chain reaction (PCR) primers based on this sequence and the conserved trypsin active site were used to amplify a DNA fragment that facilitated isolation of the corresponding genomic clone from a lambda library of S. nodorum. The full-length sequence confirmed its identity as a trypsin-like protease containing the N-terminal sequence of the previously purified enzyme. Infected leaf tissue contained a protease, not present in controls, that coeluted with the fungal trypsin from cation exchange, and had properties (pI and inhibitor characteristics) similar to those of the fungal trypsin. SNP1 expression in planta was detected by Northern (RNA) blotting, reverse transcription PCR, and green fluorescent protein confocal microscopy. SNP1 released hydroxyproline from wheat cell walls. The release of hydroxyproline, together with its early expression in planta, suggests that SNP1 participates in the degradation of host cell walls during infection.

The membrane-permeabilizing effect of avenacin A-1 involves the reorganization of bilayer cholesterol

Avenacin A-1 is a member of a group of naturally occurring compounds called saponins. It is found in oat plants, where it protects against fungal pathogens. A combined electrical and optical chamber was used to determine the interaction of avenacin A-1 with Montal-Mueller planar lipid bilayers. This system allowed simultaneous measurement of the effect of avenacin A-1 on the fluorescence and lateral diffusion of a fluorescent lipid probe and permeability of the planar lipid bilayer. As expected, cholesterol was required for avenacin A-1-induced bilayer permeabilization. The planar lipid bilayers were also challenged with monodeglucosyl, bis-deglucosyl, and aglycone derivatives of avenacin A-1. The results show that the permeabilizing activity of the native avenacin A-1 was completely abolished after one, two, or all three sugar residues are hydrolyzed (monodeglucosyl, bis-deglucosyl, and aglycone derivatives, respectively). Fluorescence recovery after photobleaching (FRAP) measurements on cholesterol-containing planar lipid bilayers revealed that avenacin A-1 caused a small but significant reduction in the lateral diffusion of the phospholipid probe N-(7-nitrobenzoyl-2-oxa-1,3-diazol-4-yl)-1, 2-dihexadecanoyl-sn-glycero-3-phosphoethanolamine (NBD-PE). Similarly, with the sterol probe (22-(N-(7-nitrobenz-2-oxa-1, 3-diazol-4-yl)amino)-23,24-bisnor-5-cholen-3beta-ol (NBD-Chol), avenacin A-1, but not its derivatives, caused a more pronounced reduction in the lateral diffusion than that observed with the phospholipid probe. The data indicate that an intact sugar moiety of avenacin A-1 is required to reorganize membrane cholesterol into pores.

Fungal pathogens of oat roots and tomato leaves employ closely related enzymes to detoxify different host plant saponins

Antifungal saponins are produced by many plants and have been implicated as preformed determinants of resistance to fungal attack. The importance of saponin detoxification in fungal pathogenesis has recently been demonstrated for the fungus Gaeumannomyces graminis var. avenae, which produces the enzyme avenacinase. Avenacinase detoxifies the triterpenoid oat root saponin avenacin A-1, and is essential for pathogenicity of G. graminis var.avenae to oats. Here we demonstrate an unexpected relatedness between avenacinase and the tomatinase enzyme produced by Septoria lycopersici (a tomato leaf-infecting fungus), which acts on the steroidal glycoalkaloid alpha-tomatine. The two enzymes share common physicochemical properties and are immunologically cross-reactive; however, there are critical differences in their substrate specificities which reflect the host preferences of the fungi from which the enzymes were purified. The DNA encoding tomatinase was isolated from a S. lycopersici cDNA library using avenacinase DNA as a probe. Comparison of the predicted amino acid sequences of avenacinase and tomatinase revealed that the enzymes are clearly similar.

Host range of a plant pathogenic fungus determined by a saponin detoxifying enzyme

Antifungal saponins occur in many plant species and may provide a preformed chemical barrier to attack by phytopathogenic fungi. Some fungal pathogens can enzymatically detoxify host plant saponins, which suggests that saponin detoxification may determine the host range of these fungi. A gene encoding a saponin detoxifying enzyme was cloned from the cereal-infecting fungus Gaeumannomyces graminis. Fungal mutants generated by targeted gene disruption were no longer able to infect the saponin-containing host oats but retained full pathogenicity to wheat (which does not contain saponins). Thus, the ability of a phytopathogenic fungus to detoxify a plant saponin can determine its host range.

An "instant gene bank" method for heterologous gene cloning: complementation of two Aspergillus nidulans mutants with Gaeumannomyces graminis DNA

We present a novel technique for gene cloning by complementation of mutations in Aspergillus nidulans with DNA from a heterologous organism, Gaeumannomyces graminis. This technique bypasses the time-consuming and difficult construction of gene libraries, making it both rapid and simple. The method relies on recombination between a fungal replicating vector pHELP1 and linear G. graminis genomic DNA during co-transformation. We were able to complement two out of seven A. nidulans mutants tested and to rescue transforming DNA from both in Escherichia coli. Complementation of the A. nidulans argB mutation resulted from integration of 8-10 kb segments of G. graminis DNA into pHELP1. The complementation of the A. nidulans pyrG mutation resulted from a complex rearrangement. Complementing DNA was shown to originate from G. graminis, and was capable of retransforming the original mutants to give the expected phenotype.