Let's just ask them. Perspectives on urban dwelling and air quality: A cross-sectional survey of 3,222 children, young people and parents

This research aimed to capture and synthesise the views of children, young people, parents and expectant parents (CYPP) about the cities where they live, with a specific focus on air pollution (AP), in order to support the generation of evidence-informed policy that reflects CYPP's perspectives, ultimately contributing to the development of child-centered, healthier, sustainable cities. The Children, Cities and Climate (CCC) project used targeted social media adverts to recruit CYPP to complete an online survey with a combination of open and closed questions in order to collect perceptions about air quality in their home cities, the main sources of AP, and how they would improve their cities. The survey was completed by 3,222 CYPP in 59 of the most polluted cities in 14 countries. Nearly two in five (39%) CYPP cited AP as one of the worst things about their city, with motor transport perceived as the main contributor. CYPP reported differing views on whether their cities were becoming better (43%) or worse (34%) places to live (33% reported it was 'staying the same'). Numerous specific ideas to improve cities and urban air quality emerged, alongside an emphasis on also addressing structural barriers to change. A clear set of principles that should guide how city leaders act was also described, including the need to engage with young people meaningfully. CYPPs articulated good and bad experiences of urban living and perceived AP and traffic as pressing concerns. They provided a clear set of suggestions for improving their cities. Further efforts to engage young people on these issues are warranted.

A health sector response to the commercial determinants of health

AIM

To develop and apply a theoretical framework to assess the rigour of a district health organisation's response to the commercial determinants of health (CDoH).

METHODS

The multi-method study incorporated literature reviews of CDoH strategies and ways in which organisations can respond; policy document review; and 12 qualitative, semi-structured, key informant interviews.

RESULTS

A theoretical framework was developed summarising CDoH and potential responses. The organisation has relevant policies, including those concerning corporate relationships and conflict of interest; however, there are opportunities to strengthen policy content and processes. Key themes were identified based on key informants' perceptions: 1) disconnect between community impacts of harmful commodities and awareness/action on CDoH drivers of these impacts; 2) power imbalance between harmful commodity industries and communities; and 3) need for a robust, values-based, Tiriti-aligned response to CDoH.

CONCLUSIONS

The health sector has an important role to play in redressing the power imbalance between harmful commodity industries and communities. Responses include: raising awareness about CDoH; strengthening policies related to interactions with corporations, and in particular considering alignment of values; supporting community actions; and advocating for legislative changes which restrict the power of harmful industries and support healthy environments and communities.

Bacillus Calmette-Guerin (BCG) induces superior anti-tumour responses by Vδ2+ T cells compared with the aminobisphosphonate drug zoledronic acid

Vδ2⁺ T cells can recognize malignantly transformed cells as well as those infected with mycobacteria. This cross-reactivity supports the idea of using mycobacteria to manipulate Vδ2⁺ T cells in cancer immunotherapy. To date, therapeutic interventions using Vδ2⁺ T cells in cancer have involved expanding these cells in or ex vivo using zoledronic acid (ZA). Here, we show that the mycobacterium Bacillus Calmette–Guérin (BCG) also causes Vδ2⁺ T-cell expansion in vitro and that resulting Vδ2⁺ cell populations are cytotoxic toward tumour cell lines. We show that both ZA and BCG-expanded Vδ2+ cells effectively killed both Daudi and THP-1 cells. THP-1 cell killing by both ZA and BCG-expanded Vδ2+ cells was enhanced by treatment of targets cells with ZA. Although no difference in cytotoxic activity between ZA- and BCG-expanded Vδ2+ cells was observed, BCG-expanded cells degranulated more and produced a more diverse range of cytokines upon tumour cell recognition compared to ZA-expanded cells. ZA-expanded Vδ2+ cells were shown to upregulate exhaustion marker CD57 to a greater extent than BCG-expanded Vδ2+ cells. Furthermore, ZA expansion was associated with upregulation of inhibitory markers PD-1 and TIM3 in a dose-dependent manner whereas PD-1 expression was not increased following expansion using BCG. Intradermal BCG vaccination of rhesus macaques caused in vivo expansion of Vδ2⁺ cells. In combination with the aforementioned in vitro data, this finding suggests that BCG treatment could induce expansion of Vδ2⁺ T cells with enhanced anti-tumour potential compared to ZA treatment and that either ZA or BCG could be used intratumourally as a means to potentiate stronger anti-tumour Vδ2⁺ T-cell responses.

780 IMPROVING NUTRITIONAL SUPPORT FOR POST-SURGICAL FEMUR FRACTURE PATIENTS AT ST MARY’S HOSPITAL, LONDON

Introduction

Malnutrition represents a common complication in femur fracture patients and is primarily caused by poor dietary intake. Malnutrition is associated with poor clinical outcomes, and is the strongest independent risk factor for recurrent femur fracture. High protein oral nutrition supplements (ONS) have been associated with improved clinical outcomes after femur fracture, including reduced complications, length of hospital stay, mortality and bone mineral density loss, and increases in functional status and quality of life (Volkert, Beck, Cederholm et al., Clinical Nutrition, 38, 10–47)). Accordingly, the European Society for Clinical Nutrition and Metabolism (ESPEN) advocates the use of ONS with all femur fracture patients in hospital.

Aim To improve nutritional support for post-surgical femur fracture patients at St Mary’s Hospital, London.

Methods

We plan to carry out three PDSA cycles to evaluate whether two separate interventions are effective in increasing the prescription rate of ONS in post-surgical femur patients. Each PDSA cycle included all patients who underwent surgical treatment for femur fracture during a one month period.

Results

‘Cycle 1’ included 18 patients (mean age: 84.6 years; range: 68–98 years) treated in March 2021. ONS were prescribed in 11% (2/18) post-surgical femur fracture patients. ‘Intervention 1’ comprised a dietician-led presentation during the Geriatric department weekly teaching session on 17/05/21. ‘Cycle 2’ data will be collected one month after ‘Intervention 1’.

Conclusion

‘Cycle 1’ results revealed low rates of ONS prescriptions for post-surgical femur patients. We anticipate higher ONS prescription rates following ‘Intervention 1’. We believe that doctors’ and dieticians’ awareness of the importance of nutritional support for post-surgical femur fracture patients is key to the success of this quality improvement project.

A Web-Based Alcohol Risk Communication Tool: Development and Pretesting Study

Background

Alcohol use is a major public health concern associated with an increased risk of morbidity and mortality. Health professionals in primary care commonly see patients with a range of alcohol-related risks and problems, providing an ideal opportunity for screening and brief intervention (BI).

Objective

This study aimed to develop a prototype for a Web-based tool for use by primary care health professionals (eg, doctors and nurses) to communicate alcohol harm risk to their patients and to engage with them regarding ways this risk could be reduced.

Methods

Following conceptualization and development of prototype wireframes, formative work and pretesting were undertaken. For the formative work, focus groups and key informant interviews were conducted with potential end users of the risk communication tool, including health professionals and consumers. The focus groups and interviews explored perceptions of alcohol risk communication and obtained feedback on the initial prototype. For pretesting, participants (primary care doctors and nurses) completed a Web-based survey followed by a period of pretesting before completion of a follow-up survey. The study was designed to gain feedback on the tool’s performance in real-world settings as well as its relevance, ease of use, and any suggested refinements.

Results

In the formative work stage, 11 key informants and 7 consumers participated in either focus groups or individual interviews. Participants were very positive about the prototype and believed that it would be useful and acceptable in practice. Key informants identified that the key point of difference with the tool was that it provided all the pieces in 1 place (ie, assessment, interpretation, and resources to support change). Participants provided feedback on how the tool could be improved, and these suggestions were incorporated into the prototype where possible. In the pretesting stage, 7 people (5 doctors and 2 primary care nurses) completed the pretesting. Participants reported that the tool provided a useful framework for an intervention, that it would be acceptable to patients, that it was easy to use, that they would be likely to use it in practice, and that there were no technical issues.

Conclusions

The alcohol risk communication tool was found to be acceptable and has the potential to increase the confidence of health professionals in assessing risk and providing BI.

Computed Tomography-Based Biomarker for Longitudinal Assessment of Disease Burden in Pulmonary Tuberculosis

PURPOSE

Computed tomography (CT) images enable capturing specific manifestations of tuberculosis (TB) that are undetectable using common diagnostic tests, which suffer from limited specificity. In this study, we aimed to automatically quantify the burden of Mycobacterium tuberculosis (Mtb) using biomarkers extracted from x-ray CT images.

PROCEDURES

Nine macaques were aerosol-infected with Mtb and treated with various antibiotic cocktails. Chest CT scans were acquired in all animals at specific times independently of disease progression. First, a fully automatic segmentation of the healthy lungs from the acquired chest CT volumes was performed and air-like structures were extracted. Next, unsegmented pulmonary regions corresponding to damaged parenchymal tissue and TB lesions were included. CT biomarkers were extracted by classification of the probability distribution of the intensity of the segmented images into three tissue types: (1) Healthy tissue, parenchyma free from infection; (2) soft diseased tissue, and (3) hard diseased tissue. The probability distribution of tissue intensities was assumed to follow a Gaussian mixture model. The thresholds identifying each region were automatically computed using an expectation-maximization algorithm.

RESULTS

The estimated longitudinal course of TB infection shows that subjects that have followed the same antibiotic treatment present a similar response (relative change in the diseased volume) with respect to baseline. More interestingly, the correlation between the diseased volume (soft tissue + hard tissue), which was manually delineated by an expert, and the automatically extracted volume with the proposed method was very strong (R² ≈ 0.8).

CONCLUSIONS

We present a methodology that is suitable for automatic extraction of a radiological biomarker from CT images for TB disease burden. The method could be used to describe the longitudinal evolution of Mtb infection in a clinical trial devoted to the design of new drugs.

Effect of a text message intervention on alcohol-related harms and behaviours: secondary outcomes of a randomised controlled trial

OBJECTIVE

Mobile Health approaches show promise as a delivery mode for alcohol screening and brief intervention. The 'YourCall' trial evaluated the effect of a low-intensity mobile phone text message brief intervention compared with usual care on hazardous drinking and alcohol-related harms among injured adults. This paper extends our previously published primary outcome analysis which revealed a significant reduction in hazardous drinking associated with the intervention at 3 months, with the effect maintained across 12 months follow-up. The objective of the current study was to evaluate the effect of the intervention on alcohol-related harms and troubles and help-seeking behaviours (secondary outcomes) at 12-months follow-up.

RESULTS

A parallel two-group, single-blind, randomised controlled trial was conducted in 598 injured inpatients aged 16-69 years identified as having medium-risk hazardous drinking. Logistic regression models applied to 12-month follow-up data showed no significant differences between intervention and control groups in self-reported alcohol-related harms and troubles and help-seeking behaviours. Although this text message intervention led to a significant reduction in hazardous alcohol consumption (previously published primary outcome), changes in self-reported alcohol-related harms and troubles and help seeking behaviours at 12-months follow up (secondary outcomes) were small and non-significant.

TRIAL REGISTRATION

ACTRN12612001220853. Retrospectively registered 19 November 2012.

Using Exploratory Trials to Identify Relevant Contexts and Mechanisms in Complex Electronic Health Interventions: Evaluating the Electronic Patient-Reported Outcome Tool

Background

Designing appropriate studies for evaluating complex interventions, such as electronic health solutions to support integrated care, remains a methodological challenge. With the many moving parts of complex interventions, it is not always clear how program activities are connected to anticipated and unanticipated outcomes. Exploratory trials can be used to uncover determinants (or mechanisms) to inform content theory that underpins complex interventions before designing a full evaluation plan.

Objective

A multimethod exploratory trial of the electronic patient-reported outcome (ePRO) tool was conducted to uncover contexts, processes and outcome variables, and the mechanisms that link these variables before full-scale evaluation. ePRO is a mobile app and portal designed to support goal-oriented care in interdisciplinary primary health care practices (clinical-level integration). This paper offers evaluation findings and methodological insight on how to use exploratory trial data to identify relevant context, process, and outcome variables, as well as central (necessary to achieving outcomes) versus peripheral (less critical and potentially context dependent) mechanisms at play.

Methods

The 4-month trial was conducted in 2 primary health care practices in Toronto, Canada. The patients were randomized into control and intervention groups and compared pre and post on quality of life and activation outcome measures. Semistructured interviews were conducted with providers and patients in the intervention group. Narrative analysis was used to uncover dominant mechanisms that inform the intervention’s content theory (how context and process variables are linked to outcomes).

Results

Overall, 7 providers, 1 administrator, and 16 patients (7-control, 9-intervention) participated in the study. This study uncovered many complex and nuanced context, process, and outcome variables at play in the intervention. Narrative analysis of patient and provider interviews revealed dominant story lines that help to tease apart central and peripheral mechanisms driving the intervention. Provider and patient story lines centered around fitting the new intervention into everyday work and life of patients and providers and meaningfulness of the intervention. These themes were moderated by patient-provider relationships going into and throughout the intervention, their comfort with technology, and the research process.

Conclusions

Identifying dominant story lines using narrative analysis helps to identify the most relevant context and process variables likely to influence study outcomes. Normalization process theory emerges as a useful theory to uncover underlying mechanisms because of its emphasis on the social production and normalization of technological, processual, and social aspects of work; all found to be critical to our intervention. The number of complex, overlapping influencing variables suggests that complex interventions such as ePRO require us to pay careful attention to central versus peripheral mechanisms that will influence study outcomes. The narrative methods presented here are shown to be useful in uncovering these mechanisms and help to guide subsequent larger evaluation studies.

The Optimization of an eHealth Solution (Thought Spot) with Transition-Aged Youth in Postsecondary Settings: Participatory Design Research

BACKGROUND

Seventy percent of lifetime cases of mental illness emerge before the age of 24 years, but many youth are unable to access the support and services they require in a timely and appropriate way. With most youth using the internet, electronic health (eHealth) interventions are promising tools for reaching this population. Through participatory design research (PDR) engagement methods, Thought Spot, a Web- and mobile-based platform, was redeveloped to facilitate access to mental health services by transition-aged youth (aged 16-29 years) in postsecondary settings.

OBJECTIVE

The aim of this study was to describe the process of engaging with postsecondary students through the PDR approaches, with the ultimate goal of optimizing the Thought Spot platform.

METHODS

Consistent with the PDR approaches, five student-led workshops, attended by 41 individuals, were facilitated to obtain feedback regarding the platform's usability and functionality and its potential value in a postsecondary setting. Various creative engagement activities were delivered to gather experiences and opinions, including semistructured focus groups, questionnaires, personas, journey mapping, and a world café. Innovative technological features and refinements were also brainstormed during the workshops.

RESULTS

By using PDR methods of engagement, participants knew that their ideas and recommendations would be applied. There was also an overall sense of respect and care integrated into each group, which facilitated an exchange of ideas and suggestions.

CONCLUSIONS

The process of engaging with students to redesign the Thought Spot platform through PDR has been effective. Findings from these workshops will significantly inform new technological features within the app to enable positive help-seeking behaviors among students. These behaviors will be further explored in the second phase that involves a randomized controlled trial.

Mobile Web-Based Follow-up for Postoperative ACL Reconstruction: A Single-Center Experience

Background

The initial 6 weeks after surgery has been identified as an area for improvement in patient care. During this period, the persistence of symptoms that go unchecked can lead to unscheduled emergency room and clinic visits, calls to surgeons' offices, and readmissions.

Purpose

To analyze postoperative data from a previous study examining postoperative outcomes in 2 patient populations following breast reconstruction and anterior cruciate ligament (ACL) reconstruction with use of a patient-centered mobile application. Here, the authors establish whether this method of follow-up can provide useful insight specific to the orthopaedic patient population, and they determine whether the mobile platform has the potential to modify their postoperative treatment. In addition, the authors examine its utility for orthopaedic physicians and patients.

Study Design

Case series; Level of evidence, 4.

Methods

Eligible patients undergoing ACL reconstruction from 2 surgeons were consecutively recruited to use a mobile smartphone application that allowed physicians to monitor their recovery at home. Data from 32 patients were collected via the application and analyzed to evaluate recovery trends during the first 6 postoperative weeks. Following completion of the study, patients and physicians were interviewed on their experience.

Results

Data collected from each question in the mobile application provided insightful trends on daily real-time indicators of postoperative recovery. The application identified 1 patient who required in-person reassessment to rule out a possible infection, following surgeon review of an uploaded image. It was estimated that the majority of patients could have avoided follow-up at 2 and 6 weeks, owing to the application's efficacy. Participants described their satisfaction with the device as excellent (43%), good (40%), fair (10%), and poor (7%), and 94% (n = 30) of patients reported that they would respond to questions using a similar application in the future. Both physicians rated their experience as positive and identified useful traits in the web portal.

Conclusion

This system can accurately assess patient recovery; it has the potential to change how postoperative orthopaedic patients are followed, and it is well received by patients and physicians. Recognition of the study's limitations and employment of user feedback to improve the current application are essential before a formal randomized controlled trial is conducted.

Effectiveness of the YourCall™ text message intervention to reduce harmful drinking in patients discharged from trauma wards: protocol for a randomised controlled trial

BACKGROUND

Behavioural brief interventions (BI) can support people to reduce harmful drinking but multiple barriers impede the delivery and equitable access to these. To address this challenge, we developed YourCall™, a novel short message service (SMS) text message intervention incorporating BI principles. This protocol describes a trial evaluating the effectiveness of YourCall™ (compared to usual care) in reducing hazardous drinking and alcohol related harm among injured adults who received in-patient care.

METHODS/DESIGN

Participants recruited to this single-blind randomised controlled trial comprised patients aged 16-69 years in three trauma-admitting hospitals in Auckland, New Zealand. Those who screened positive for moderately hazardous drinking were randomly assigned by computer to usual care (control group) or the intervention. The latter comprised 16 informational and motivational text messages delivered using an automated system over the four weeks following discharge. The primary outcome is the difference in mean AUDIT-C score between the intervention and control groups at 3 months, with the maintenance of the effect examined at 6 and 12 months follow-up. Secondary outcomes comprised the health and social impacts of heavy drinking ascertained through a web-survey at 12 months, and further injuries identified through probabilistic linkage to national databases on accident insurance, hospital discharges, and mortality. Research staff evaluating outcomes were blinded to allocation. Intention-to-treat analyses will include assessment of interactions based on ethnicity (Māori compared with non-Māori).

DISCUSSION

If found to be effective, this mobile health strategy has the potential to overcome current barriers to implementing equitably accessible interventions that can reduce harmful drinking.

TRIAL REGISTRATION

Universal Trial Number (UTN) U1111-1134-0028. ACTRN12612001220853 . Submitted 8 November 2012 (date of enrolment of first participant); Version 1 registration confirmed 19 November 2012. Retrospectively registered.

Enhancing Self-Efficacy for Help-Seeking Among Transition-Aged Youth in Postsecondary Settings With Mental Health and/or Substance Use Concerns, Using Crowd-Sourced Online and Mobile Technologies: The Thought Spot Protocol

Background

Seventy percent of lifetime cases of mental illness emerge prior to age 24. While early detection and intervention can address approximately 70% of child and youth cases of mental health concerns, the majority of youth with mental health concerns do not receive the services they need.

Objective

The objective of this paper is to describe the protocol for optimizing and evaluating Thought Spot, a Web- and mobile-based platform cocreated with end users that is designed to improve the ability of students to access mental health and substance use services.

Methods

This project will be conducted in 2 distinct phases, which will aim to (1) optimize the existing Thought Spot electronic health/mobile health intervention through youth engagement, and (2) evaluate the impact of Thought Spot on self-efficacy for mental health help-seeking and health literacy among university and college students. Phase 1 will utilize participatory action research and participatory design research to cocreate and coproduce solutions with members of our target audience. Phase 2 will consist of a randomized controlled trial to test the hypothesis that the Thought Spot intervention will show improvements in intentions for, and self-efficacy in, help-seeking for mental health concerns.

Results

We anticipate that enhancements will include (1) user analytics and feedback mechanisms, (2) peer mentorship and/or coaching functionality, (3) crowd-sourcing and data hygiene, and (4) integration of evidence-based consumer health and research information.

Conclusions

This protocol outlines the important next steps in understanding the impact of the Thought Spot platform on the behavior of postsecondary, transition-aged youth students when they seek information and services related to mental health and substance use.

Alternative BCG delivery strategies improve protection against Mycobacterium tuberculosis in non-human primates: Protection associated with mycobacterial antigen-specific CD4 effector memory T-cell populations

Intradermal (ID) BCG injection provides incomplete protection against TB in humans and experimental models. Alternative BCG vaccination strategies may improve protection in model species, including rhesus macaques. This study compares the immunogenicity and efficacy of BCG administered by ID and intravenous (IV) injection, or as an intratracheal mucosal boost (ID + IT), against aerosol challenge with Mycobacterium tuberculosis Erdman strain. Disease pathology was significantly reduced, and survival improved, by each BCG vaccination strategy, relative to unvaccinated animals. However, IV induced protection surpassed that achieved by all other routes, providing an opportunity to explore protective immunological mechanisms using antigen-specific IFN-γ ELISpot and polychromatic flow cytometry assays. IFN-γ spot forming units and multifunctional CD4 T-cell frequencies increased significantly following each vaccination regimen and were greatest following IV immunisation. Vaccine-induced multifunctional CD4 T-cells producing IFN-γ and TNF-α were associated with reduced disease pathology following subsequent M.tb challenge; however, high frequencies of this population following M.tb infection correlated with increased pathology. Cytokine producing T-cells primarily occupied the CD4 transitional effector memory phenotype, implicating this population as central to the mycobacterial response, potentially contributing to the stringent control observed in IV vaccinated animals. This study demonstrates the protective efficacy of IV BCG vaccination in rhesus macaques, offering a valuable tool for the interrogation of immunological mechanisms and potential correlates of protection.

Technology-Enabled Remote Monitoring and Self-Management - Vision for Patient Empowerment Following Cardiac and Vascular Surgery: User Testing and Randomized Controlled Trial Protocol

Background

Tens of thousands of cardiac and vascular surgeries (CaVS) are performed on seniors in Canada and the United Kingdom each year to improve survival, relieve disease symptoms, and improve health-related quality of life (HRQL). However, chronic postsurgical pain (CPSP), undetected or delayed detection of hemodynamic compromise, complications, and related poor functional status are major problems for substantial numbers of patients during the recovery process. To tackle this problem, we aim to refine and test the effectiveness of an eHealth-enabled service delivery intervention, TecHnology-Enabled remote monitoring and Self-MAnagemenT—VIsion for patient EmpoWerment following Cardiac and VasculaR surgery (THE SMArTVIEW, CoVeRed), which combines remote monitoring, education, and self-management training to optimize recovery outcomes and experience of seniors undergoing CaVS in Canada and the United Kingdom.

Objective

Our objectives are to (1) refine SMArTVIEW via high-fidelity user testing and (2) examine the effectiveness of SMArTVIEW via a randomized controlled trial (RCT).

Methods

CaVS patients and clinicians will engage in two cycles of focus groups and usability testing at each site; feedback will be elicited about expectations and experience of SMArTVIEW, in context. The data will be used to refine the SMArTVIEW eHealth delivery program. Upon transfer to the surgical ward (ie, post-intensive care unit [ICU]), 256 CaVS patients will be reassessed postoperatively and randomly allocated via an interactive Web randomization system to the intervention group or usual care. The SMArTVIEW intervention will run from surgical ward day 2 until 8 weeks following surgery. Outcome assessments will occur on postoperative day 30; at week 8; and at 3, 6, 9, and 12 months. The primary outcome is worst postop pain intensity upon movement in the previous 24 hours (Brief Pain Inventory-Short Form), averaged across the previous 14 days. Secondary outcomes include a composite of postoperative complications related to hemodynamic compromise—death, myocardial infarction, and nonfatal stroke— all-cause mortality and surgical site infections, functional status (Medical Outcomes Study Short Form-12), depressive symptoms (Geriatric Depression Scale), health service utilization-related costs (health service utilization data from the Institute for Clinical Evaluative Sciences data repository), and patient-level cost of recovery (Ambulatory Home Care Record). A linear mixed model will be used to assess the effects of the intervention on the primary outcome, with an a priori contrast of weekly average worst pain intensity upon movement to evaluate the primary endpoint of pain at 8 weeks postoperation. We will also examine the incremental cost of the intervention compared to usual care using a regression model to estimate the difference in expected health care costs between groups.

Results

Study start-up is underway and usability testing is scheduled to begin in the fall of 2016.

Conclusions

Given our experience, dedicated industry partners, and related RCT infrastructure, we are confident we can make a lasting contribution to improving the care of seniors who undergo CaVS.

Improving Patient Experience and Primary Care Quality for Patients With Complex Chronic Disease Using the Electronic Patient-Reported Outcomes Tool: Adopting Qualitative Methods Into a User-Centered Design Approach

BACKGROUND

Many mHealth technologies do not meet the needs of patients with complex chronic disease and disabilities (CCDDs) who are among the highest users of health systems worldwide. Furthermore, many of the development methodologies used in the creation of mHealth and eHealth technologies lack the ability to embrace users with CCDD in the specification process. This paper describes how we adopted and modified development techniques to create the electronic Patient-Reported Outcomes (ePRO) tool, a patient-centered mHealth solution to help improve primary health care for patients experiencing CCDD.

OBJECTIVE

This paper describes the design and development approach, specifically the process of incorporating qualitative research methods into user-centered design approaches to create the ePRO tool. Key lessons learned are offered as a guide for other eHealth and mHealth research and technology developers working with complex patient populations and their primary health care providers.

METHODS

Guided by user-centered design principles, interpretive descriptive qualitative research methods were adopted to capture user experiences through interviews and working groups. Consistent with interpretive descriptive methods, an iterative analysis technique was used to generate findings, which were then organized in relation to the tool design and function to help systematically inform modifications to the tool. User feedback captured and analyzed through this method was used to challenge the design and inform the iterative development of the tool.

RESULTS

Interviews with primary health care providers (n=7) and content experts (n=6), and four focus groups with patients and carers (n=14) along with a PICK analysis-Possible, Implementable, (to be) Challenged, (to be) Killed-guided development of the first prototype. The initial prototype was presented in three design working groups with patients/carers (n=5), providers (n=6), and experts (n=5). Working group findings were broken down into categories of what works and what does not work to inform modifications to the prototype. This latter phase led to a major shift in the purpose and design of the prototype, validating the importance of using iterative codesign processes.

CONCLUSIONS

Interpretive descriptive methods allow for an understanding of user experiences of patients with CCDD, their carers, and primary care providers. Qualitative methods help to capture and interpret user needs, and identify contextual barriers and enablers to tool adoption, informing a redesign to better suit the needs of this diverse user group. This study illustrates the value of adopting interpretive descriptive methods into user-centered mHealth tool design and can also serve to inform the design of other eHealth technologies. Our approach is particularly useful in requirements determination when developing for a complex user group and their health care providers.

Development of a text message intervention aimed at reducing alcohol-related harm in patients admitted to hospital as a result of injury

Background

Screening for alcohol misuse and brief interventions (BIs) for harm in trauma care settings are known to reduce alcohol intake and injury recidivism, but are rarely implemented. We created the content for a mobile phone text message BI service to reduce harmful drinking among patients admitted to hospital following an injury who screen positive for hazardous alcohol use. The aim of this study was to pre-test and refine the text message content using a robust contextualisation process ahead of its formal evaluation in a randomised controlled trial.

Methods

Pre-testing was conducted in two phases. First, in-depth interviews were conducted with 14 trauma inpatients (16–60 years) at Auckland City Hospital and five key informants. Participants were interviewed face-to-face using a semi-structured interview guide. Topics explored included: opinions on text message ideas and wording, which messages did or did not work well and why, interactivity of the intervention, cultural relevance of messages, and tone of the content. In a second phase, consultation was undertaken with Māori (New Zealand’s indigenous population) and Pacific groups to explore the relevance and appropriateness of the text message content for Māori and Pacific audiences.

Results

Factors identified as important for ensuring the text message content was engaging, relevant, and useful for recipients were: reducing the complexity of message content and structure; increasing the interactive functionality of the text message programme; ensuring an empowering tone to text messages; and optimising the appropriateness and relevance of text messages for Māori and Pacific people. The final version of the intervention (named ‘YourCall^™’) had three pathways for people to choose between: 1) text messages in English with Te Reo (Māori language) words of welcome and encouragement, 2) text messages in Te Reo Māori, and 3) text messages in English (with an option to receive a greeting in Samoan, Tongan, Cook Island Māori, Niuean, Tokelauan, Tuvaluan, or Fijian).

Conclusions

We have developed a text message intervention underpinned by established BI evidence and behaviour change theory and refined based on feedback and consultation. The next step is evaluation of the intervention in a randomised-controlled trial.

Using a mobile app for monitoring post-operative quality of recovery of patients at home: a feasibility study

Background

Mobile apps are being viewed as a new solution for post-operative monitoring of surgical patients. Mobile phone monitoring of patients in the post-operative period can allow expedited discharge and may allow early detection of complications.

Objective

The objective of the current study was to assess the feasibility of using a mobile app for the monitoring of post-operative quality of recovery at home following surgery in an ambulatory setting.

Methods

We enrolled 65 consecutive patients (n=33, breast reconstruction surgery; n=32, orthopedic surgery) and asked them to use a mobile phone daily to complete a validated quality of recovery scale (QoR-9) and take photographs of the surgical site for the first 30 days post-op. Surgeons were asked to review patient-entered data on each patient in their roster daily. A semistructured questionnaire was administered to patients and surgeons to assess satisfaction and feasibility of the mobile device.

Results

All 65 patients completed the study. The mean number of logins was 23.9 (range 7-30) for the breast patients and 19.3 (range 5-30) for the orthopedic patients. The mean number of logins was higher in the first 14 days compared to the 15-30 days post-op for both breast patients (13.4 vs 10.5; P<.001) and for the orthopedic patients (13.4 vs 6.0; P<.001). The mean score for overall satisfaction with using the mobile device was 3.9 for breast patients and 3.7 for orthopedic patients (scored from 1 (poor) to 4 (excellent)). Surgeons reported on the easy-to-navigate design, the portability to monitor patients outside of hospital, and the ability of the technology to improve time efficiency.

Conclusions

The use of mobile apps for monitoring the quality of recovery in post-operative patients at home was feasible and acceptable to patients and surgeons in the current study. Future large scale studies in varying patient populations are required.

Mild traumatic brain injury: improving quality of care in the paediatric emergency department setting

AIM

Traumatic brain injury (TBI) in childhood can impose a significant threat to life and longer-term disability. This study investigated the extent to which the documentation of key indicators of healthcare quality in the emergency department (ED) setting was consistent with clinical guidelines for the management of children with mild TBI (MTBI).

METHODS

The clinical records of a random sample of 60 children (stratified by ethnicity and age group), who were seen and discharged from a large metropolitan paediatric hospital ED following a head injury, were systematically reviewed to examine the processes of care and follow-up.

RESULTS

Based on the documentation in clinical records, processes designed to identify and manage potentially life-threatening acute complications (e.g. computed tomography scanning to identify intracranial haemorrhage) were consistent with best practice standards. However gaps existed between current and best practice for some aspects of care that could minimise risks of longer-term disability from MTBI. For example, relevant clinical criteria were well documented, but this information did not appear to be applied systematically to identify and to follow up children with definite or possible MTBI.

CONCLUSION

The apparent absence of a systematic approach to the diagnosis and follow-up of MTBI in children presenting to ED suggests a missed opportunity to minimise the risk of disability following these injuries. Greater attention to an integrated care pathway that improves the identification, documentation, and follow-up of children with MTBI presenting to ED is required.

Randomized, double-blind comparison of growth in infants receiving goat milk formula versus cow milk infant formula

OBJECTIVE

To compare growth of infants fed goat milk infant formula (GMF) or cow milk infant formula (CMF) and to compare tolerability and safety of the two formulas.

METHODS

The study was conducted in Auckland, New Zealand. This was a double-blind randomized controlled trial. Newborn term infants were randomized within 72 h of birth to GMF or CMF. Milk formula powder in single serve sachets were reconstituted and fed to infants from trial commencement until age 168 days. No other formula given from randomization until age 168 days. Infant weight, length and head circumference were measured at birth and age 14, 28, 56, 84, 112, 140 and 168 days. Bowel motion frequency and consistency, sleeping and crying patterns and adverse events were also measured.

RESULTS

Seventy-two infants were randomized, 36 each to GMF or CMF, with 62 infants completing the intervention. At enrollment the average weight of infants in the GMF group (mean +/- SD) was 3.33 +/- 0.43 kg and in the CMF group 3.43 +/- 0.47 kg; and at study completion 8.07 +/- 0.90 kg (GMF) and 7.87 +/- 0.99 kg (CMF). The difference in average weight gain over the study period for the GMF group versus the CMF group was not significant (+309 g; 95% CI = -49 to +668, P = 0.09). Median daily bowel motion frequency was greater in the GMF group than the CMF group (2.4 vs 1.7, P = 0.01). There were no group differences in bowel motion consistency, duration of crying, ease of settling, or frequency of adverse events.

CONCLUSION

Growth of infants fed GMF is not different to that of infants-fed CMF.

Short-term repeatability of a food frequency questionnaire in New Zealand children aged 1–14 y

OBJECTIVE

To evaluate the repeatability of a children's food frequency questionnaire (FFQ) by gender, ethnicity, and age group.

DESIGN

A 117-item FFQ asking about food intake patterns over the past 4 weeks was developed using food records from 428 children (204 boys and 224 girls) and the reproducibility on average 13 days apart was tested in 130 children (78 boys and 52 girls). Children were recruited using clustered probability sampling (n=103), and a convenience sample of 25 Maori children.

SETTING

Children aged 1-14 y from Auckland, Feilding and Shannon, New Zealand.

SUBJECTS

There were 71 Maori, 20 Pacific, and 39 Other children.

RESULTS

Spearman correlations between the two FFQs ranged from 0.50 for bread to 0.82 for fruit, with a median of 0.76 for spreads and nonmilk drinks, and Cronbach's coefficient alpha's ranged from 0.59 for bread to 0.92 for nonmilk drinks, with a median of 0.85 for mixed meat dishes. There were no significant differences between the two administrations, apart from reporting higher intakes of vegetables and snacks & sweets in the first FFQ. Correlation coefficients tended to be slightly higher in boys than in girls, and in Other ethnic groups compared to Maori and Pacific children. Correlations were slightly higher for the 1-4 y age group, intermediate in the 10-14 y age group, and lowest in the 5-9 y-old age group.

CONCLUSIONS

Overall, the FFQ described here shows similar or better repeatability in New Zealand children of all major ethnic groups compared to other child or adolescent FFQs.

Analysis of SIV-specific CTL in the rhesus macaque model of AIDS: the use of simian fibroblasts as an alternative source of target cells for chromium release assays

The simian immunodeficiency virus (SIV) model of AIDS is widely used for the development of human immunodeficiency virus (HIV) vaccine strategies, particularly for the analysis of correlates of protective immunity. As it is not always possible to establish autologous B-lymphoblastoid cell lines (B-LCL) for use as targets in the analysis of cytotoxic T cell (CTL) activity, we have compared B-LCL with primary simian skin cells. Using a well-defined SIV gag-encoded CTL epitope restricted by Mamu A*01 major histocompatibility complex (MHC) class I, we have shown that peripheral blood mononuclear cells (PBMC) from vaccinated and infected macaques can kill MHC class I-matched skin fibroblasts presenting the cognate epitope but that skin fibroblasts are a less sensitive target than B-LCL for the detection of CTL.

Structural implications of a Val-->Glu mutation in transmembrane peptides from the EGF receptor

Certain specific point mutations within the transmembrane domains of class I receptor tyrosine kinases are known to induce altered behavior in the host cell. An internally controlled pair of peptides containing the transmembrane portion of the human epidermal growth factor (EGF) receptor (ErbB-1) was examined in fluid, fully hydrated lipid bilayers by wide-line 2H-NMR for insight into the physical basis of this effect. One member of the pair encompassed the native transmembrane sequence from ErbB-1, while in the other the valine residue at position 627 was replaced by glutamic acid to mimic a substitution that produces a transformed phenotype in cells. Heteronuclear probes having a defined relationship to the peptide backbone were incorporated by deuteration of the methyl side chains of natural alanine residues. 2H-NMR spectra were recorded in the range 35 degrees C to 65 degrees C in membranes composed of 1-palmitoyl-2-oleoyl phosphatidylcholine. Narrowed spectral components arising from species rotating rapidly and symmetrically within the membrane persisted to very high temperature and appeared to represent monomeric peptide. Probes at positions 623 and 629 within the EGF receptor displayed changes in quadrupole splitting when Val(627) was replaced by Glu, while probes downstream at position 637 were relatively unaffected. The results demonstrate a measurable spatial reorientation in the region of the 5-amino acid motif (residues 624-628) often suggested to be involved in side-to-side interactions of the receptor transmembrane domain. Spectral changes induced by the Val-->Glu mutation in ErbB-1 were smaller than those induced by the analogous oncogenic mutation in the homologous human receptor, ErbB-2 (Sharpe, S., K. R. Barber, and C. W. M. Grant. 2000. Biochemistry. 39:6572-6580). Quadrupole splittings at probe sites examined were only modestly sensitive to temperature, suggesting that each transmembrane peptide behaved as a motionally ordered unit possessing considerable conformational stability.

Lack of a role for transforming growth factor-beta in cytotoxic T lymphocyte antigen-4-mediated inhibition of T cell activation

Similarities in the phenotypes of mice deficient for cytotoxic T lymphocyte antigen-4 (CTLA-4) or transforming growth factor-beta1 (TGF-beta1) and other observations have led to speculation that CTLA-4 mediates its inhibitory effect on T cell activation via costimulation of TGF-beta production. Here, we examine the role of TGF-beta in CTLA-4-mediated inhibition of T cell activation and of CTLA-4 in the regulation of TGF-beta production. Activation of AND TCR transgenic mouse T cells with costimulatory receptor-specific antigen presenting cells results in efficient costimulation of proliferation by CD28 ligation and inhibition by CTLA-4 ligation. Neutralizing antibody to TGF-beta does not reverse CTLA-4-mediated inhibition. Also, CTLA-4 ligation equally inhibits proliferation of wild-type, TGF-beta1(-/-), and Smad3(-/-) T cells. Further, CTLA-4 engagement does not result in the increased production of either latent or active TGF-beta by CD4(+) T cells. These results indicate that CTLA-4 ligation does not regulate TGF-beta production and that CTLA-4-mediated inhibition can occur independently of TGF-beta. Collectively, these data demonstrate that CTLA-4 and TGF-beta represent distinct mechanisms for regulation of T cell responses.

A transmembrane peptide from the human EGF receptor: behaviour of the cytoplasmic juxtamembrane domain in lipid bilayers

Solid state (2)H NMR spectroscopy was employed to study peptides related to the transmembrane domain of the human epidermal growth factor receptor, for insight into the interaction of its cytoplasmic juxtamembrane domain with the membrane surface. Since such receptors have clusters of (+)charged amino acids in this region, the effect of (-)charged phosphatidylserine at the concentration found naturally in the cytoplasmic leaflet (15 mol%) was considered. Each peptide contained 34 amino acids, which included the hydrophobic 23 amino acid stretch thought to span the membrane and a ten amino acid segment beyond the 'cytoplasmic' surface. Non-perturbing deuterium probe nuclei were located within alanine side chains in intramembranous and extramembranous portions. (2)H NMR spectra were recorded at 35 degrees C and 65 degrees C in fluid lipid bilayers consisting of (zwitterionic) 1-palmitoyl-2-oleoylphosphatidylcholine, with and without 15 mol% (anionic) phosphatidylserine. The cationic extramembranous portion of the receptor backbone was found to be highly rotationally mobile on a time scale of 10(-4)-10(-5) s in both types of membrane - as was the alpha-helical intramembranous portion. Deuterium nuclei in alanine side chains (-CD(3)) detected modest changes in peptide backbone orientation and/or dynamics related to the presence of 1-stearoyl-2-oleoylphosphatidylserine: in the case of the extramembranous portion of the peptide these seemed related to lipid charge. Temperature effects on the peptide backbone external to the membrane were qualitatively different from effects on the helical transmembrane domain - likely reflecting the different physical constraints on these peptide regions and the greater flexibility of the extramembranous domain. Effects related to lipid charge could be detected in the spectrum of CD(3) groups on the internally mobile side chain of Val(650), six residues beyond the membrane surface.

Val(659)-->Glu mutation within the transmembrane domain of ErbB-2: effects measured by (2)H NMR in fluid phospholipid bilayers

Certain point mutations within the hydrophobic transmembrane domains of class I receptor tyrosine kinases have been associated with oncogenic transformation in vitro and in vivo [Gullick, J., and Srinivasan, R. (1998) Breast Cancer Res. Treat. 52, 43-53]. An important example is the replacement of a single (hydrophobic) valine by (charged) glutamate in the rat protein, Neu, and in the homologous human protein, ErbB-2. It has been suggested that the oncogenic nature of this Val-->Glu substitution may derive from alteration of the transmembrane domain's ability to take part in direct side-to-side associations. In the present work, we examined the basis of this phenomenon by studying transmembrane portions of ErbB-2 in fluid bilayer membranes. An expression system was designed to produce such peptides from the wild-type ErbB-2, and from an identical region of the transforming mutant in which Val(659) is replaced by Glu. All peptides were 50-mers, containing the appropriate transmembrane domain plus contiguous stretches of amino acids from the cytoplasmic and extracellular domains. Deuterium heteronuclear probes were incorporated into alanine side chains (thus, each alanine -CH(3) side chain became -CD(3)). Given the presence of natural alanine residues at positions 648 and 657 within ErbB-2, this approach afforded heteronuclear probes within the motif Ser(656)AlaValValGlu(660), thought to be important for homodimer formation, and nine residues upstream of this site. Further peptides were produced, by site-directed mutagenesis, to confirm spectral assignments and to provide an additional probe location at position 670 (11 residues downstream of the motif region). On SDS-polyacrylamide gels, the transmembrane peptides migrated as predominant monomers in equilibrium with smaller populations of homodimers/-oligomers. CD spectra of both wild-type and transforming mutant peptides were consistent with the transmembrane portions being basically alpha-helical. (2)H NMR spectra of each transmembrane peptide were obtained in fluid phospholipid bilayers of 1-palmitoyl-2-oleoylphosphatidylcholine (POPC) from 35 to 65 degrees C. Results were consistent with the concept that the glutamic acid residue characterizing the mutant is uncharged at neutral pH. Narrowed spectral components from species rotating rapidly and symmetrically within the membrane appeared to represent monomeric peptide. Mutation of Val(659) to Glu within the hydrophobic domain induced changes in side chain angulation of at least 6-8 degrees at Ala(657) (i.e., within the five amino acid motif thought to be involved in homodimer formation), and downstream of this site to residue 670. There was little evidence of effect at the upstream site (Ala(648)) at the membrane surface. This result argues that the transforming mutation is associated with significant intramolecular rearrangement of the monomeric transmembrane helix-extending over some four helix turns-which could influence its lateral associations. In addition, temperature effects on spectral quadrupole splittings suggested that there is greater peptide backbone flexibility for the wild-type transmembrane region.

Expression and membrane assembly of a transmembrane region from Neu

Transmembrane domains of receptor tyrosine kinases are increasingly seen as key modulatory elements in signaling pathways. The present work addresses problems surrounding expression, isolation, secondary structure recovery, and assembly into membranes, of the relatively large quantities of transmembrane peptides needed to investigate these pathways by NMR spectroscopy. We demonstrate significant correspondence between SDS-PAGE behavior of such peptides and their (2)H NMR spectra in lipid bilayer membranes. A 50-residue peptide, Neu(exp), containing the transmembrane portion of the receptor tyrosine kinase, Neu, was designed for expression in Escherichia coli. The sequence also contained 11-12 amino acids from each side of the transmembrane domain. The common problem of low expressivity of transmembrane peptides was encountered-likely associated with membrane toxicity of the desired gene product. This difficulty was overcome by expressing the peptide as a TrpE fusion protein in a pATH vector to target expression products to inclusion bodies, and subsequently removing the TrpE portion by cyanogen bromide cleavage. Inclusion bodies offered the additional benefits of reduced proteolytic degradation and simplified purification. The presence of a hexa-His tag allowed excellent recovery of the final peptide, while permitting use of denaturing solvents and avoiding the need for HPLC with its attendant adsorption losses. Isolated expressed peptides were found to be pure, but existed as high oligomers rich in beta-structure as evidenced by CD spectroscopy and SDS-PAGE behavior. Dissolution in certain acidic organic solvents led to material with increased alpha-helix content, which behaved in detergent as mixtures of predominantly monomers and dimers-a situation often considered to exist in cell membranes. For purposes of NMR spectroscopy, peptide alanine residues were deuterated in high yield during expression. The same acidic organic solvents used to dissolve and dissociate expressed transmembrane peptides proved invaluable for their assembly into lipid bilayers. Analogous transmembrane peptides from the human receptor tyrosine kinase, ErbB-2, demonstrated related phenomena.

Alloantigen-stimulated anti-HIV activity

A number of studies have suggested that an immune response to human leukocyte antigen (HLA) alloantigens may contribute to protection against HIV infection. In the present study, we examined the effect of alloantigen-stimulated cell lines obtained from peripheral blood mononuclear cells (PBMC) of HIV-uninfected (HIV-) individuals and the soluble factors produced by these cell lines on HIV-1 replication. Multiple in vitro restimulation with irradiated allogeneic PBMC from HIV- donors resulted in the expansion of CD8(+) T-cell lines that inhibited HIV-1 replication when cocultured with either autologous or heterologous in vitro-infected phytohemagglutinin (PHA) blasts. Supernatants from the alloantigen-stimulated cell lines also inhibited HIV replication in both PHA blasts and a chronically infected cell line. The alloantigen-stimulated cell lines and the factors they produced inhibited both T-cell-tropic (T) and macrophage-tropic (M) isolates of HIV-1. Blocking experiments using anti-chemokine antibodies suggested that this inhibition of HIV replication was not due to the beta-chemokines present in cocultures of cell lines with HIV-infected blasts. These results indicate that alloantigen-stimulation of PBMC from HIV- individuals activates CD8(+) T cells that produce soluble factor(s) that inhibit HIV replication of a wide spectrum of HIV-1 isolates through a chemokine-independent mechanism. This is a US government work. There are no restrictions on its use.

Anti-major histocompatibility complex antibody responses to simian B cells do not protect macaques against SIVmac infection

Macaques have been protected against infection with human cell-grown SIVmac by immunization with antigens encoded by the human major histocompatibility complex (MHC). Here, we investigated the efficacy of alloimmunization with simian B cells expressing high levels of MHC class I and class II molecules to confer protection against systemic challenge with simian-grown SIVmac. Eight rhesus macaques were vaccinated with glutaraldehyde-fixed and beta-propiolactone-inactivated herpesvirus papio-transformed B cells. Four of the macaques received 5 doses, the others 10. Animals were challenged with rhesus macaque spleen-derived cell-free SIVmac. Allogeneic B cells elicited antibody responses to rhesus MHC class I and II but failed to protect animals against infection. Anti-MHC class I antibodies were restricted in specificity and failed to recognize MHC class I from some B lymphoblastoid cell lines (B-LCLs) including a B-LCL from the animal in whose cells the challenge virus was grown. Vaccinated animals responded to self-MHC class I antigens but not to self-MHC class II antigens from peripheral blood mononuclear cells (PBMCs). Animals that underwent the shorter immunization regimen had transiently enhanced PBMC-associated virus loads after challenge, whereas the average virus-infected cell load was reduced in animals that underwent the more extensive immunization. These results suggest that antibody responses to allogeneic MHC molecules do not protect against infection with immunodeficiency lentiviruses.

Neutralization of a clade B primary isolate by sera from human immunodeficiency virus-uninfected recipients of candidate AIDS vaccines

The inability of antibodies induced by experimental human immunodeficiency virus type 1 (HIV-1) vaccines to neutralize HIV-1 primary isolates may be due to a failure to elicit such antibodies, antigenic differences between the vaccine and the strains tested, insensitivity of the assays used, or to a combination of factors. New neutralization assays were used to determine the ability of candidate AIDS vaccines to generate neutralizing antibodies for clade B primary isolate BZ167, which is closely related in portions of its envelope to the immunizing strains. Sera from HIV-uninfected volunteers in vaccine trials were tested, and neutralizing activity was found in recipients of recombinant (r) gp120MN or of rgp160MN-containing canarypox boosted with rgp120SF-2. Detection of antibodies that neutralize primary isolate BZ167 correlated with neutralizing activity for homologous vaccine strains. These data demonstrate that certain candidate AIDS vaccines can elicit antibodies that neutralize a primary isolate of HIV-1.

Dietary fat and asthma: is there a connection?

The last two decades have seen an increase in the prevalence of asthma, eczema, and allergic rhinitis in developed countries. This increase has been paralleled by a fall in the consumption of saturated fat and an increase in the amount of polyunsaturated fat in the diet. This is due to a reduction in the consumption of animal fat and an increase in the use of margarine and vegetable oils containing omega-6 polyunsaturated fatty acids (PUFAs), such as linoleic acid. There is also evidence for a decrease in the consumption of oily fish which contain omega-3 PUFAs, such as eicosapentaenoic acid. In a number of countries, there are social class and regional differences in the prevalence of allergic disease, which are associated with differences in the consumption of PUFAs. Linoleic acid is a precursor of arachidonic acid, which can be converted to prostaglandin E2 (PGE2), whereas eicosapentaenoic acid inhibits the formation of PGE2. PGE2 acts on T-lymphocytes to reduce the formation of interferon-gamma (IFN-gamma) without affecting the formation of interleukin-4 (IL-4). This may lead to the development of allergic sensitization, since IL-4 promotes the synthesis of immunoglobulin E (IgE), whereas IFN-gamma has the opposite effect. Changes in the diet may explain the increase in the prevalence of asthma, eczema and allergic rhinitis. The effects of diet may be mediated through an increase in the synthesis of prostaglandin E2 which in turn can promote the formation of immunoglobulin E.

A resting cell assay for improved detection of antibody-mediated neutralization of HIV type 1 primary isolates

The sensitivity with which antibody-mediated neutralization is detected in vitro is dependent on the virus, the antibody, the target cells, and the culture conditions used in the assay. Using activated and transformed target cells, the ability of various culture-adapted and primary strains of HIV-1 to be neutralized by different polyclonal and monoclonal antibody preparations has been thoroughly studied. However, the vast majority of HIV-1-susceptible CD4+ cells in vivo are not activated or transformed, but are quiescent. Because resting lymphocytes can be infected with HIV-1, we initiated studies to determine (1) if the use of resting lymphocytes as target cells would result in a neutralization assay with increased sensitivity, (2) if the degree of target cell activation had a measurable effect on the sensitivity with which antibody-mediated neutralization could be detected, and (3) whether, using a more sensitive assay, neutralizing antibodies in patients' sera might be detectable that had been below the threshold of detection when using "conventional" assays. The experiments described in the studies below reveal that an inverse relationship exists between the level of target cell activation and the sensitivity with which neutralization can be detected. Moreover, using an assay in which unstimulated peripheral blood mononuclear cells serve as target cells, experiments show that antibody-mediated neutralization of primary and prototype laboratory isolates of HIV-1 can be detected with 10- to 100-fold greater sensitivity than when stimulated peripheral blood mononuclear cells are used as target cells. With this resting cell assay, neutralizing activity can be detected in the sera of HIV-positive subjects that, by previously used "conventional" neutralization assays, was undetectable.

Repair and evolution of nef in vivo modulates simian immunodeficiency virus virulence

Experimental evidence from the simian immunodeficiency virus (SIV) model of AIDS has shown that the nef gene is critical in the pathogenesis of AIDS. Consequently, nef is of considerable interest in both antiviral drug and vaccine development. Preliminary findings in two rhesus macaques indicated that a deletion of only 12 bp found in the overlapping nef/3' long terminal repeat (LTR) region (9501 to 9512) of the SIVmacC8 molecular clone was associated with reduced virus isolation frequency. We show that this deletion can be repaired in vivo by a sequence duplication event and that sequence evolution continues until the predicted amino acid sequence of the repair is virtually indistinguishable from that of the virulent wild type. These changes occurred concomitantly with reversion to virulence, evidenced by a high virus isolation frequency and load, decline in anti-p27 antibody, substantial reduction in the CD4/CD8 ratio, and development of opportunistic infections associated with AIDS. These findings clearly illustrate the capacity for repair of small attenuating deletions in primate lentiviruses and also strongly suggest that the region from 9501 to 9512 in the SIV nef/3' LTR region is of biological relevance. In addition, the ability of attenuated virus to revert to virulence raises fundamental questions regarding the nature of superinfection immunity.

Antibodies to the HIV-1 V3 loop in serum from infected persons contribute a major proportion of immune effector functions including complement activation, antibody binding, and neutralization

Previous studies have shown that the V3 region of the HIV envelope is both critical to viral functions and immunogenic. However, the relative contribution of anti-V3 antibodies in the sera of infected individuals in mediating immune effector functions directed at whole intact virus and infected cells has not been determined. This study used peptides corresponding to several regions of the HIV envelope as inhibitors of antibody binding and antibody effector functions directed at virions and virus-infected cells in order to assess the relative importance of V3-specific antibodies in sera from infected persons. Approximately 40% of the antibody in serum which could bind to native viral proteins on HIVMN-infected cells was blocked by a peptide corresponding to the central 15 amino acids of the V3 loop. In contrast, little if any blocking of serum antibody binding was observed with peptides corresponding to flanking regions of HIVMN V3 or three regions of gp41. Since antiviral antibody can also activate immune effector functions, we determined whether peptides could block antibody-dependent activation of the complement system by HIV-infected cells or free virus. Surprisingly, the V3 loop peptide blocked 75-95% of complement activation on HIV-infected cells. While the V3 loop peptide also blocked a substantial portion of the neutralizing activity in serum from infected persons for free virus it was again more effective in inhibiting complement-mediated effects on free virus. Accordingly, antibody-dependent, complement-mediated virolysis was inhibited by 61-79%. The results of these experiments indicate that (1) a substantial portion (30-40%) of the antibody in sera from infected persons that is capable of binding to HIV-infected cells and HIV virions is V3-specific, and (2) these V3-specific antibodies are particularly important for complement activation on infected cells and virions. This indicates that the central portion of the V3 loop, while constituting less than 3% of the amino acid sequence of the HIV envelope, apparently provides a major gp160 site for immune effector functions, especially complement activation.