Perceptions of mental health providers of the barriers and facilitators of using and engaging youth in digital mental-health-enabled measurement based care

Objectives

Increased rates of mental health disorders and substance use among youth and young adults have increased globally, furthering the strain on an already burdened mental health system. Digital solutions have been proposed as a potential option for the provision of timely mental health services for youth, with little research exploring mental health professional views about using such innovative tools. In Alberta, Canada, we are evaluating the implementation and integration of a digital mental health (dMH) platform into existing service pathways. Within this paper we seek to explore mental health professionals' perceptions of the barriers and facilitators that may influence their utilization of digital MH-enabled measurement-based care (MBC) with the youth who access their services.

Methods

A qualitative, descriptive methodology was used to inductively generate themes from focus groups conducted with mental health professionals from specialized mental health services and primary care networks in Alberta.

Results

As mental health professionals considered the barriers and facilitators of using dMH with youth, they referenced individual and family barriers and facilitators to consider. Providers highlighted perceived barriers, including: first, cultural stigma, family apprehension about mental health care, and parental access to dMH and MBC as deterrents to providers adopting digital platforms in routine care; second, perceptions of increased responsibility and liability for youth in crisis; third, perception that some psychiatric and neurodevelopmental disorders in youth are not amenable to dMH; fourth, professionals contemplated youth readiness to engage with dMH-enabled MBC. Participants also highlighted pertinent facilitators to dMH use, noting: first, the suitability of dMH for youth with mild mental health concerns; second, youth motivated to report their changes in mental health symptoms; and lastly, youth proficiency and preference for dMH options.

Conclusions

By identifying professionals' perceptions of barriers and facilitators for youth users, we may better understand how to address misconceptions about who is eligible and appropriate for dMH through training and education.

Social research to understand farmer and agricultural stakeholder attitudes towards bovine tuberculosis vaccination of cattle

BACKGROUND

This social research study employed a behavioural insights framework, Easy, Attractive, Social, Timely ('EAST'), to identify cues that may influence farmer and stakeholder attitudes towards the deployment of CattleBCG vaccine.

METHODS

The EAST framework was employed to develop policy scenarios consisting of several cues likely to affect vaccine uptake. These scenarios consisted of a government-led approach, an individual farmer-led approach, and a third approach, also farmer-led but organised collectively. The government approach was mandatory, while the farmer-led approaches were both voluntary. The scenarios were tested during farmer participatory workshops (n = 8) and stakeholder interviews (n = 35).

RESULTS

Overall, the EAST framework provided a useful approach for gathering behavioural insights around attitudes towards cattle vaccination. We found an overall receptiveness towards the idea of vaccinating cattle against bovine tuberculosis, particularly where clear, transparent messaging around the likely efficacy is mobilised, where clarity around potential implications for trading is provided, and where vaccine doses are provided free of charge and administered by veterinarians and veterinary technicians. In general, these factors were a pre-requisite to a mandatory (government-led) national approach, which was the preferred deployment mechanism among farmers and stakeholders. However, these conditions would also likely facilitate a voluntary vaccination programme.

LIMITATIONS

Trust in those involved in delivering a vaccine programme and trust in the vaccine itself represent a crucial aspect of farmer and stakeholder attitudes towards cattle vaccination; however, this aspect was not covered by the EAST framework.

CONCLUSION

EAST provided a novel framework for examining attitudes towards cattle vaccination with CattleBCG, although we recommend incorporating a 'trust' component in future iterations.

Emergency Medicine Virtual Conference Participants’ Engagement with Competing Activities

Introduction: Residency didactic conferences transitioned to a virtual format during the COVID-19 pandemic. This format creates questions about effective educational practices, which depend on learner engagement. In this study we sought to characterize the competitive demands for learner attention during virtual didactics and to pilot methodology for future studies. Methods: This was a prospective, observational, cohort study of attendees at virtual didactics from a single emergency medicine residency, which employed a self-report strategy informed by validated classroom assessments of student engagement. We deployed an online, two-question survey polling across six conference days using random signaled sampling. Participants reported all activities during the preceding five minutes. Results: There were 1303 responses over 40 survey deployments across six nonadjacent days. Respondents were residents (63.4%); faculty (27.5%); fellows (2.3%); students (2%); and others (4.8%). Across all responses, about 85% indicated engagement in the virtual conference within the last five minutes of the polls. The average number of activities engaged in was 2.0 (standard deviation = 1.1). Additional activities included education-related (34.2%), work-related (21.1%), social (18.8%), personal (14.6%), self-care (13.4%), and entertainment (4.4%). Conclusion: Learners engage in a variety of activities during virtual didactics. Engagement appears to fluctuate temporally, which may inform teaching strategies. This information may also provide unique instructor feedback. This pilot study demonstrates methodology for future studies of conference engagement and learning outcomes.

Tongue protrusion as the presenting symptom of parapharyngeal abscess

Deep neck space infections are commonly seen in the pediatric population. The diagnosis, however, can be challenging to make and requires a high degree of suspicion because of developmental and age-related factors in children and non-specific presenting symptoms. Diagnosis becomes further complicated in patients whose comorbid conditions mask some of the more severe systemic symptoms. We present a case of a 2-year-old female with Trisomy 21 who presented with a chief concern of "tongue swelling" per parents. After initially failing treatment for presumed angioedema caused by an angiotensin-converting enzyme inhibitor, she was ultimately diagnosed with a parapharyngeal abscess with extension and mass effect causing tongue protrusion. This case represents a novel early presentation of a common infection and highlights the challenges of diagnosing deep neck space infections in children.

Dementia Care Across Long-Term Settings: Similar but Not Equal

Nursing homes and assisted living (AL) communities are similar but not equal, and addressing the needs of residents with dementia differs across settings. It is important to appreciate that both settings are complex adaptive systems; as such, care intended to have widespread impact must be mindful of stakeholders, understand existing practices, and be pragmatic. This session will present an evidence-based program developed in nursing homes – Mouth Care Without a Battle, which teaches staff to provide daily, personalized mouth care to persons with cognitive and physical impairment – and considerations relevant for implementation in AL. Using data from more than 2,000 AL trainees and also AL administrators, supervisors, residents, family members, and trainers, it will situate findings in the context of implementation science and the NIH Stage Model, thereby making them applicable to any dementia care practice regardless its focus and the setting in which it is to be used.

The five-beat averaged method of assessing aortic stenosis in atrial fibrillation significantly underestimates stenosis severity compared to sinus rhythm

Background

Doppler echocardiographic assessment of aortic stenosis (AS) is dependent on trans-valvular flow rate (TVFR) and is most accurately performed in physiologically normal conditions (TVFR >200ml/s). Atrial fibrillation (AF) complicates AS assessment with heart rate variability and reduced averaged indexed stroke volume (SVi) compared to sinus rhythm (SR). We hypothesize that the 5-beat averaging technique in AF leads to underestimation of severity of AS compared to SR, and that diagnostic accuracy may be improved by maximum SVi beat selection.

Methods

Patients with at least mild AS (mean aortic gradient (MG) >15mmHg) with separate echocardiograms demonstrating SR and AF within a six-month period were identified. Patients with interval cardiac surgery, change in left ventricular ejection fraction (LVEF) of >15%, aortic valve prostheses, infective endocarditis, paced rhythm, severe concomitant valvular dysfunction, LVEF <35%, heart rate >100 beats per minute (bpm) or TVFR <200ml/s on their SR examination were excluded. In AF, individual beat SVi was calculated from individual beat aortic velocity time integral (VTI) and the reported aortic valve area (AVA) via the continuity equation.

Results

Seventeen patients were identified (mean time between echocardiograms 132 days, mean difference in LVEF 4%, mean difference in heart rate 11bpm). Using the 5-beat averaged model, compared to SR, the presence of AF significantly reduced SVi (−12.68ml/m2, p=0.00007) and TVFR (−69ml/s, p=0.00014). In AF, 9/17 cases demonstrated one or more beats with TVFR <200ml/s, with 6/17 producing a 5-beat averaged TVFR <200ml/s – consistent with a low flow state. Correspondingly, flow derived severity assessment parameters and calculated aortic valve area (AVA) in AF were reduced compared to SR (aortic peak velocity (Vmax) −0.42m/s, p=0.00005, MG −7.01mmHg, p=0.002, AVA −0.11cm2, p=0.025). As a proposed correction in AF, the single beat with the largest SVi was compared with SR. This measure improved concordance with flow conditions and severity assessment in SR (difference SVi −8.77ml/m2, p=0.004, TVFR −46ml/s, p=0.001, Vmax −0.21, p=0.003, MG −3.55mmHg, p=0.02) and equalized calculated AVA (−0.07cm2, p=0.09).

Conclusion

In individual patients with AS observed in SR and AF within a six-month period, AF was associated with significantly lower SVi and TVFR, with underestimation of AS severity assessment. AS assessment in AF using maximum observed stroke volume beat (as opposed to 5-beat average) improves concordance with SR assessment significantly.

Funding Acknowledgement

Type of funding source: None

Improving the Pediatric Emergency Department Learning Experience: A Simulation-Based Orientation for Pediatric PGY 1 Residents

INTRODUCTION

Rotations in the pediatric emergency department (PED) may expose residents to very few critically ill patients. In our previous work, interns at our institution showed low self-confidence in decision-making and preparedness to stabilize acutely ill patients. In order to improve this, we designed a new, peer-led, simulation-based orientation to the PED rotation for interns focusing on workflow and decision-making. The cases presented learners with practical and generalizable challenges, such as ordering initial labs and medications and defining the ultimate disposition for the patient.

METHODS

This orientation curriculum was designed for first-year residents using high-fidelity simulation mannequins. In the first of two cases, learners managed a 10-year-old boy presenting with status asthmaticus who required continuous albuterol and parenteral magnesium to achieve stability for admission. In the second case, a 4-year-old girl with short gut syndrome and an indwelling central line presented with fever, was found to be septic, but responded well to fluid resuscitation and antibiotic therapy.

RESULTS

Over 2 years of implementation, 39 residents participated. Pre- and postintervention Likert-based survey evaluations showed significant increases in confidence in decision-making and preparedness to stabilize acutely ill children that were not seen in a control group during the pilot year. A subsequent class-wide implementation showed similar significant improvements, as well as increased comfort initiating treatment prior to staffing.

DISCUSSION

Using simulation mannequins in a case-based orientation can improve PGY 1 residents' self-confidence and sense of preparedness during their first rotation in the PED.

A specialised pollination system using nectar-seeking thynnine wasps in Caladenia nobilis (Orchidaceae)

Caladenia is a diverse Australian genus that is exceptional among orchids in having both species pollinated by food-seeking and sexually deceived insects. Here, we investigated the pollination of Caladenia nobilis, a species predicted to be food-deceptive due to its large, cream-coloured and apparently nectarless flowers. Pollinator observations were made using experimental clumps of flowers. Measurements of floral colour were undertaken with a spectrometer, nectar was tested using GC-MS, and reproductive success was quantified for 2 years. While C. nobilis attracted nine species of insect, only males of the thynnine wasp Rhagigaster discrepans exhibited the correct size and behaviour to remove and deposit pollen. Male R. discrepans attempted to feed from the surface of the labellum, often crawling to multiple flowers, but showed no evidence of sexual attraction. Most flowers produced little or no nectar, although some may provide enough sucrose to act as a meagre reward to pollinators. Floral colouration was similar to a related Caladenia species pollinated by sexual deception, although the sexually deceptive species had a dull-red labellum. Reproductive success was generally low and highly variable between sites and years. In addition to most visitors being of inappropriate size for pollinia removal, the lack of response to the orchid by several co-occurring species of thynnine wasp suggests filtering of potential pollinators at the attraction phase. Our discovery of a pollination strategy that may be intermediate between food deception and food reward raises the question, how many putatively rewardless orchids actually produce meagre amounts of nectar?

Advances in Medical Education and Implications for the Pediatric Emergency Department

The learning environment of the pediatric emergency department is composed of many layers that provide opportunity for intervention to improve the education of residents and medical students. Creating an intentional plan of targeted interventions at the levels of learner, teacher, and department can create a culture where education is highly regarded. This article briefly defines the learning environment and explores strategies for improving clinical teaching at these various levels through improved teacher-learner relationships, entrustment, and the implementation of teaching strategies that can be easily incorporated into the busy and time-stretched work of the pediatric emergency department.

Redefining the Team in Team-Based Care: Role of Public Health

In North Carolina, our public health infrastructure consists of a state health department and 85 local health departments representing all 100 counties. The state health department, local health departments, health systems, and clinical providers work literally and figuratively as a team to improve the health of our citizens. In this article, we provide examples of the critical role of public health practitioners as part of the broader team addressing health, specifically in the areas of chronic disease, communicable disease, oral health, environmental health, and maternal and child health.

Patients' knowledge and views of their depot neuroleptic medication

Aims and method

This study examined the attitudes and knowledge of patients regarding their depot neuroleptic medication. All patients were attending a community mental health centre in Clydebank, Scotland.

Results

Many patients had limited knowledge of their medication, its benefits and side-effects as well as the rationale for its use. The biggest gaps were found in patients' knowledge of the long-term side-effects of their medication.

Clinical implications

Our findings raise doubts as to the capacity of some patients to give informed consent to their treatment. A number of steps are outlined in order to raise patients' standard of knowledge.

Accuracy of Smartphone-Based Pulse Oximetry Compared with Hospital-Grade Pulse Oximetry in Healthy Children

BACKGROUND

Pulse oximetry, a ubiquitous, noninvasive method to monitor oxygen saturation (SpO₂), requires larger, nonportable equipment. Smartphone pulse oximeter applications (apps) provide a portable, cost-effective option, but are untested in children. We hypothesize that smartphone pulse oximetry will not be inferior to standard pulse oximetry measured in healthy children.

MATERIALS AND METHODS

Two main types of pulse oximetry apps, a camera-based app (CBA) that uses a phone camera flash and lens and a probe-based app (PBA) that uses an external plug-in probe, were compared with standard pulse oximetry measured in children ages 2-13 years without a respiratory complaint and a triage SpO₂ ≥97% seen in a pediatric Emergency Department. Two investigators obtained heart rate and SpO₂ using each app. Inter-rater reliability was tested using interclass correlations (ICCs), and Bland-Altman method was used to compare app values to triage measurements.

RESULTS

Eighty-one patients were enrolled. ICC for SpO₂ for PBA and CBA were 0.73 and -0.24, respectively. The 95% limits of agreement between the PBA SpO₂ and triage SpO₂ were -2.8 to +2.5 compared with -4.1 to +3.5 for the CBA SpO₂ and triage SpO₂. Mean differences between triage SpO₂ and the PBA SpO₂ (-0.17%) and triage SpO₂ and CBA SpO₂ (-0.33%) were not statistically significant.

DISCUSSION AND CONCLUSIONS

Smartphone-based pulse oximetry is not inferior to standard pulse oximetry in pediatric patients without hypoxia. Reliability was superior for PBA compared with CBA, with more precise agreement for the PBA compared with the CBA. Future studies should test pulse oximetry apps in a hypoxic pediatric population.

Adherence to Adjuvant Endocrine Therapy in Christchurch Women with Early Breast Cancer

AIMS

To assess adherence to adjuvant endocrine therapy by a real-world cohort of women in Christchurch and to determine any associated factors.

MATERIALS AND METHODS

Records were retrieved of all women newly diagnosed with early breast cancer and registered on the Christchurch Breast Cancer Patient Register over 4 years from June 2009. Demographic and pathological factors, dates of starting and stopping endocrine therapies and reported side-effects were collected. The proportion remaining on endocrine therapy was analysed by Kaplan-Meier curve; Cox regression analysis was used to identify independent factors influencing adherence.

RESULTS

Of 1213 women, 1018 (83.9%) had oestrogen receptor-positive tumours, of whom 674 (66.2%) started adjuvant endocrine therapy, including 62 (9.2%) neoadjuvantly. Uptake was 52.4% of those with T1 tumours, 89% with T2 tumours, 93% with T3/T4 tumours, 92.7% with node-positive tumours and 49.7% with node-negative tumours. The initial endocrine therapy was an aromatase inhibitor in 254 (38%) and tamoxifen for 412 (61%). At 1 year, 90% remained adherent, at 2 years 84%, at 3 years 81%, at 4 years 76%, at 4.5 years 71% and at 5 years 50%, with a median duration of 60 months (56-64 months, 95% confidence interval) and a median follow-up of 33 months. Overall, 135 (20%) women stopped treatment for adverse events or poor tolerability. A longer persistence with endocrine therapy was associated with node-positive tumours (hazard ratio 1.38, P = 0.003), but not first hormone used; aromatase inhibitor compared with tamoxifen, P = 0.76.

CONCLUSION

Adjuvant endocrine therapy use fell to 50% by 5 years, limiting possible survival benefits, providing support for efforts to increase compliance.

Using Twitter to increase content dissemination and control educational content with Presenter Initiated and Generated Live Educational Tweets (PIGLETs)

Live-tweeting during educational presentations is typically learner-generated and can lead to misquoted information. Presenter curated tweets have not been well described. We created Presenter Initiated and Generated Live Educational Tweets (PIGLETs) with the goal to broaden the reach of educational conferences. We hypothesized that using PIGLETs would increase the reach and exposure of our material. We developed a prospective single-arm intervention study performed during the "Not Another Boring Lecture" workshops presented at two national conferences in 2015. Presenters tweeted PIGLETs linked to unique hashtags #NotAnotherBoringLecture and #InnovateMedEd. Analytic software was used to measure the following outcomes: (1) number of tweets published by presenters versus learners, (2) reach (users exposed to content containing the hashtag), and (3) exposure (total number of times content was delivered). One hundred and twenty-six participants attended the workshops. A total of 636 tweets (including retweets) were sent by presenters containing the study hashtags, compared with 162 sent by learners. #NotAnotherBoringLecture reached 47,200 users and generated 136,400 impressions; #InnovateMedEd reached 36,400 users and generated 79,100 impressions. PIGLETs allowed presenters to reach a significant number of learners, as well as control the content delivered through Twitter. PIGLETs can be used to augment educational sessions beyond the physical confines of the classroom.

Regulation of the alternative pathway of complement modulates injury and immunity in a chronic model of dextran sulphate sodium-induced colitis

The role of complement in inflammatory bowel disease (IBD) has been studied primarily using acute models, and it is unclear how complement affects processes in more relevant chronic models of IBD in which modulation of adaptive immunity and development of fibrosis have pathogenic roles. Using mice deficient in C1q/mannose-binding lectin (MBL) or C3, we demonstrated an important role for these opsonins and/or the classical pathway C3 convertase in providing protection against mucosal injury and infection in a model of chronic dextran sulphate sodium (DSS)-induced colitis. In contrast, deficiency of the alternative pathway (fB(-/-) mice) had significantly less impact on injury profiles. Consequently, the effect of a targeted inhibitor of the alternative pathway was investigated in a therapeutic protocol. Following the establishment of colitis, mice were treated with CR2-fH during subsequent periods of DSS treatment and acute injury (modelling relapse). CR2-fH significantly reduced complement activation, inflammation and injury in the colon, and additionally reduced fibrosis. Alternative pathway inhibition also altered the immune response in the chronic state in terms of reducing numbers of B cells, macrophages and mature dendritic cells in the lamina propria. This study indicates an important role for the alternative pathway of complement in the pathogenesis and the shaping of an immune response in chronic DSS-induced colitis, and supports further investigation into the use of targeted alternative pathway inhibition for the treatment of IBD.

A novel protocol allowing oral delivery of a protein complement inhibitor that subsequently targets to inflamed colon mucosa and ameliorates murine colitis

While there is evidence of a pathogenic role for complement in inflammatory bowel disease, there is also evidence for a protective role that relates to host defence and protection from endotoxaemia. There is thus concern regarding the use of systemic complement inhibition as a therapeutic strategy. Local delivery of a complement inhibitor to the colon by oral administration would ameliorate such concerns, but while formulations exist for oral delivery of low molecular weight drugs to the colon, they have not been used successfully for oral delivery of proteins. We describe a novel pellet formulation consisting of cross-linked dextran coated with an acrylic co-polymer that protects the complement inhibitor CR2-Crry from destruction in the gastrointestinal tract. CR2-Crry containing pellets administered by gavage, were characterized using a therapeutic protocol in a mouse model of dextran sulphate sodium (DSS)-induced colitis. Oral treatment of established colitis over a 5-day period significantly reduced mucosal inflammation and injury, with similar therapeutic benefit whether or not the proton pump inhibitor, omeprazole, was co-administered. Reduction in injury was associated with the targeting of CR2-Crry to the mucosal surface and reduced local complement activation. Treatment had no effect on systemic complement activity. This novel method for oral delivery of a targeted protein complement inhibitor will reduce systemic effects, thereby decreasing the risk of opportunistic infection, as well as lowering the required dose and treatment cost and improving patient compliance. Furthermore, the novel delivery system described here may provide similar benefits for administration of other protein-based drugs, such as anti-tumour necrosis factor-α antibodies.

Natural human immunity to trypanosomes

Complement-dependent destruction of invading micro-organisms is a crucial first-line defense against infection, yet both African and American trypanosomes are able to resist attack by complement. African trypanosomes resist non-specific complement attack by virtue of a thick glycoprotein surface coat, and the host range of certain African trypanosomes is believed to be defined by their susceptibility to a subclass of human high density lipoprotein (HDL) and/or a high molecular weight protein complex present in human serum. In the first part of this review, Stephen Tomlinson and Jayne Raper look at the properties and mechanisms of action of these trypanolytic factors on African trypanosomes, and discuss briefly the possible mechanisms whereby these human pathogens resist lysis by human serum. The mechanisms that enable the American trypanosome Trypanosoma cruzi to resist complement attack are reviewed in the second part of this article.

Enhanced Recovery after Surgery Program for Elective Abdominal Surgery at Three Victorian Hospitals

The aim of this study was to evaluate the anaesthesia care of an enhanced recovery after surgery (ERAS) program for patients having abdominal surgery in Victorian hospitals. The main outcome measure was the number of ERAS items implemented following introduction of the ERAS program. Secondary endpoints included process of care measures, outcomes and hospital stay. We used a before-and-after design; the control group was a prospective cohort (n=154) representing pre-existing practice for elective abdominal surgical patients from July 2009. The introduction of a comprehensive ERAS program took place over two months and included the education of surgeons, anaesthetists, nurses and allied health professionals. A postimplementation cohort (n=169) was enrolled in early 2010. From a total of 14 ERAS-recommended items, there were significantly more implemented in the post-ERAS period, median 8 (interquartile range 7 to 9) vs 9 (8 to 10), P <0.0001. There were, however, persistent low rates of intravenous fluid restriction (25%) and early removal of urinary catheter (31%) in the post-ERAS period. ERAS patients had less pain and faster recovery parameters, and this was associated with a reduced hospital stay, geometric mean (SD) 5.7 (2.5) vs 7.4 (2.1) days, P=0.006. We found that perioperative anaesthesia practices can be readily modified to incorporate an enhanced recovery program in Victorian hospitals.

Ecology of the Honey possum, Tarsipes rostratus, in Scott National Park, Western Australia

The Honey possum, Tarsipes rostratus, is an obligate nectarivore, known to feed on plant species from only three Families in south-western Western Australia: Myrtaceae, Proteaceae and Epacridaceae. These plants can be adversely affected by fire, decreased rainfall or groundwater levels and the pathogen Phytophthora cinnamomi. We investigated the ecology of T. rostratus in terms of: (i) how the population fluctuated in response to rainfall and fire over a 20-year period and (ii) changes in diet and movements during a period of decreased food availability in late summer. Mean capture rates were significantly positively correlated with mean flowering rates of Banksia ilicifolia over a 20-year period. Winter capture rates were also significantly positively correlated with both annual and winter rainfall two years prior to trapping in recently burnt areas, but not in long unburnt� areas. Capture rates were significantly higher in unburnt Banksia woodland during winter but densities there have declined since 1996, associated with the death of many Banksia ilicifolia trees from persistent Phytophthora infection. Notwithstanding this decline, winter capture rates in the unburnt areas were still approximately double those in the burnt areas 6 years after the last fire. Short-term capture rates were negatively correlated with barometric pressure, showing that movement and foraging is stimulated by the passage of low pressure frontal weather systems. Despite the paucity of known food sources flowering in late summer and autumn, there was no evidence of T. rostratus using plant species from other than the three above-noted Families. Utilisation areas in summer were also no larger than those previously recorded across all seasons in Scott National Park. Some individuals, however, moved extensive distances to locate spatially restricted food sources. The conservatism of their diet and the sensitivity of the population to changes in rainfall and fire history indicate that T. rostratus populations are particularly vulnerable to some of the environmental changes now occurring in south-western Australia.

Upregulation of two BH3-only proteins, Bmf and Bim, during TGFβ-induced apoptosis

Transforming growth factor-beta (TGFbeta)-activated signalling pathways can lead to apoptosis, growth arrest or promotion of malignant behaviour, dependent on cellular context. The molecular mechanisms involved in TGFbeta-induced apoptosis remain controversial; although changes in gene expression are thought to be pivotal to the process, several different candidate apoptotic initiators and mediators have been proposed. Smad4, a critical component of the TGFbeta-induced transcriptional machinery, is shown here to be essential for induction of apoptosis. Gene expression analysis identified the proapoptotic Bcl-2 family members, Bmf and Bim, as induced by TGFbeta, dependent on both Smad4 and p38 function and the generation of reactive oxygen species. TGFbeta-induced Bmf and Bim localize to cellular membranes implicated in apoptosis. Inhibition of the TGFbeta-induced expression of both these proteins together provides significant protection of cells from apoptosis. The TGFbeta-triggered cell death programme thus involves induction of multiple BH3-only proteins during the induction of apoptosis.

Combined therapeutic use of AdGFPFasL and small molecule inhibitors of ceramide metabolism in prostate and head and neck cancers: a status report

As of January 2005, there were 1020 gene therapy clinical trials ongoing worldwide with 675 or 66.2% devoted to cancer gene therapy. The majority are occurring in the US and Europe (http://www.wiley.co.uk/genetherapy/clinical/). At the present time, to our knowledge there are no trials that employ gene delivery of Fas Ligand (FasL). As an important note, and in contrast to somatic cell therapy trials, there are no reported deaths due to therapeutic vector administration in any cancer gene therapy trial. That said, from our studies and from the published literature, the issue of gene delivery remains the major obstacle to successfully employing gene therapy for cancer treatment. Numerous laboratories are studying this with many different approaches. My co-workers and I have focused on the delivery issue by using various approaches that address tumor targeting and transgene expression. In addition, we are focusing on enhancing tumor cell killing via the bystander effect and through use of small molecules to enhance bystander activity.

A novel epitope of CD59 expressed by primitive human hematopoietic progenitors

OBJECTIVE

The aim of this study was to determine the identity of the cell surface molecule on primitive hematopoietic cells recognized by monoclonal antibody HCC-1.

MATERIALS AND METHODS

Screening of a cDNA expression library prepared from human bone marrow stromal cells with HCC-1 yielded a single cDNA, which when expressed in FDCP-1 cells, resulted in the specific acquisition of HCC-1 binding. The cDNA demonstrated complete identity with CD59, a phosphoinositol glycan-linked membrane protein that protects cells against autologous complement attack. The ubiquitous expression of CD59 is in marked contrast to the restricted reactivity of HCC-1. Studies were performed to examine the basis for the novel specificity of HCC-1 for CD59. The epitope on CD59 identified by HCC-1 was mapped using a series of rat/human CD59 chimeric proteins. Immunoprecipitation analyses were performed to determine whether CD59 associates with other membrane proteins.

RESULTS

Mutagenesis of Asn18 did not alter the binding of HCC-1 to CD59, suggesting that N-linked carbohydrates are not responsible for the binding specificity of HCC-1. The epitope for HCC-1 was shown to differ from that identified by previously described CD59 antibodies, encompassing residues A31, L33, R55, and L59. An 80 kDa protein co-immunoprecipitated with CD59 in the HCC-1(-) cell line HL-60 but not in HCC-1(+) K562 cells.

CONCLUSION

Collectively, these data support the hypothesis that the unique specificity of HCC-1 for CD59 is due in part to recognition of a novel epitope, which is masked as a result of association with an as yet unidentified 80 kDa protein.

Complement-independent, peroxide-induced antibody lysis of platelets in HIV-1-related immune thrombocytopenia

Immunologic thrombocytopenia is seen commonly in HIV-1 infection. The pathogenesis of this problem has been unclear, but it is associated with circulating immune complexes that contain platelet membrane components and anti-platelet membrane GPIIIa49-66 IgG antibodies. These antibodies cause acute thrombocytopenia when injected into mice. We now show that purified anti-GPIIIa49-66 causes platelet fragmentation, in vitro in the absence of complement, and in vivo in wild-type and C3-deficient mice. The mechanism of complement-independent platelet lysis is shown to be caused by the antibody-induced generation of H202, as indicated by in vitro experiments with inhibitors of reactive oxygen species, and in vivo studies carried out with p47phox-deficient mice. Thus, a novel mechanism of immunologic platelet clearance is described in which an anti-platelet IgG causes platelet fragmentation via the induction of reactive oxygen species.