Co-design of an intervention to optimize mammographic screening participation in women with obesity and/or physical disabilities

BACKGROUND

Mammographic breast screening/rescreening rates are suboptimal for women with obesity and/or physical disabilities. This study describes development of an intervention framework targeting obesity- and disability-related barriers to improve participation.

METHODS

Mixed methods combined a systematic review with first-person perspectives to optimise screening engagement among women with obesity and/or physical disabilities. Phase 1 (systematic review) was conducted following the PRISMA framework. Phase 2 involved in-depth interviews with n = 8 women with lived experience of obesity and/or physical disabilities. An inductive coding approach was applied to the data which was then combined with Phase 1 results to develop the intervention framework.

RESULTS

Six studies were included in the systematic review. Tailored education based on individual risk increased willingness to undergo mammographic screening. Recommendations to improve the screening experience included partnerships with consumers, targeted messaging, and enhanced professional development for breast screening staff. Participants also identified strategies to improve the uptake of screening and the experience itself.

CONCLUSION

Development and evaluation of interventions informed by frameworks like the one developed in this study are needed to improve engagement in screening to promote regular participation among women with physical disabilities and/or obesity.

IMPLICATIONS FOR PRACTICE

Successful implementation of practice interventions co-designed by women with obesity and/or physical disabilities are likely to improve their breast screening participation. Enhanced training of radiographers aimed at upskilling in empathetic communication around required manoeuvring and potentially longer screening times for clients with obesity and/or physical disabilities may encourage more positive client practitioner interactions. Client information aimed at women with obesity should include information on how to prepare for the appointment and explain there may be equipment limitations compromising imaging which may not be completed at an initial appointment.

Community-based care needs for adults with class III obesity before and after tertiary weight management: An exploratory study

Objective

Class 3 obesity (severe obesity) is defined by a body mass index ≥40 kg/m2. Tertiary weight-management programs (WMPs) are hospital-based multidisciplinary services that aim to support individuals with severe obesity. Severe shortage of WMPs has led to waitlists and pressure on clinicians to discharge patients. Community obesity management often fails to support patients in maintaining weight loss/health gains. This study aimed to explore the needs of patients for community-based obesity care.

Methods

A qualitative study was undertaken via a tertiary WMP in Sydney, Australia. Semi-structured interviews/focus groups explored perceptions of purposively sampled patients and their clinicians on the community-based support needs of people with severe obesity. Data were audio-recorded, transcribed verbatim, and then thematically analyzed.

Results

Eleven patients and seven clinicians were interviewed. Four themes were identified: the importance of accountability and motivation to maintain weight-loss/health gains; limitations within community-based obesity management for those with severe obesity; perspectives on structured community programs for patients transitioning into/out of tertiary WMPs; and impact of mental health, stigma, and social isolation on engagement with community-based services.

Conclusions

Community-based programs are needed to support those awaiting access to tertiary WMPs and to help maintain health gains once discharged. Such programs should address issues of social isolation and integrate with current models of tertiary metabolic and primary health care.

Adequacy of health message tailoring for ethnic minorities: Pasifika communities in Sydney, Australia, during COVID-19

Ethnic minorities, such as Pasifika, residing in high-income countries were at higher risk of COVID-19 infection during the pandemic. To understand the experiences of Pasifika, including message dissemination and barriers to tailored public health messaging during the pandemic, a qualitative study was undertaken, underpinned by Laswell's Model of Communication and Bandura's social cognitive theory with data collected using Pasifika methods. Pasifika adults (n = 65) were recruited across Sydney from July 2020 to March 2022. Health care professionals (HCP) (n = 17) employed by four local health districts (LHDs) and Pasifika community-based organizations delivering multicultural COVID-19-related work within the study catchment, were also recruited. Five themes were constructed from the data of: (i) prevailing fear and uncertainty over COVID-19 infection and losing employment; (ii) limited knowledge of government perpetuating distrust in Government as a benevolent source of information; (iii) faith and trust as priorities for health decision-making; (iv) 'Coconut wireless'-the role of family, friends and community in disseminating public health messages through word of mouth; and (v) limited health literacy affecting compliance with public health orders. Community members identified important messages and resources had not been sufficiently distributed. Most HCPs understood the necessity of grassroots-level engagement but reported existing approaches were inadequate to navigate challenges. These findings highlight the need for public health promotion and communication strategies that consider both the social and cultural determinants of health. We propose a 7-point checklist as a cultural appropriateness lens to assist the development and rating of existing or new health promotion messaging and resources.

HBV prevalence in Sub-continental countries: A systematic review and meta-analysis

BACKGROUND

Hepatitis B virus (HBV) is a major source of disease burden worldwide, with an estimated 296 million individuals living with infections worldwide. Although vaccine programs exist to control infections, certain sub-populations around the world continue to have very high prevalence of HBV infection.

METHODS

A systematic search of studies of HBV published after 2010 was conducted for India, Pakistan, Bangladesh, Nepal, Sri Lanka and Bhutan. Each paper was independently screened for risk of bias and inclusion. Data were extracted from included studies before being analysed to estimate pooled prevalence, and to conduct sub-group analyses. Random-effects models were used for estimating summary prevalence due to a high level of heterogeneity between studies, and funnel plots were combined with Egger's test to assess publication bias. Meta-regression was conducted to investigate sources of between-study heterogeneity.

RESULTS

The pooled prevalence of HBV across all studies was 3% (95% CI 0.02, 0.05). For countries with multiple studies, the pooled prevalence in India was 3% (95% CI 0.02, 0.04), in Pakistan 6% (95% CI 0.03, 0.09), in Bangladesh 5% (95% CI of 0.02, 0.12), and in Nepal 1% (95% CI 0.00, 0.08). There was some evidence of publication bias, and a high level of heterogeneity across studies. Risk of bias analysis found most studies to be of fair or moderate quality.

CONCLUSIONS

The prevalence of HBV among countries in the sub-continent was higher than the global average, but was not as high as some other regions. Countries with greater numbers of displaced persons had higher prevalence of HBV, with a wide range of prevalence between subpopulations likely reflecting differential uptake, and implementation, of vaccination programs.

Using Community Based Research Frameworks to Develop and Implement a Church-Based Program to Prevent Diabetes and Its Complications for Samoan Communities in South Western Sydney

Pasifika communities bear a disproportionate burden of diabetes compared to the general Australian population. Community-based participatory research (CBPR), which involves working in partnership with researchers and communities to address local health needs, has gained prominence as a model of working with underserved communities. This paper describes how Le Taeao Afua (LTA) Samoan diabetes prevention program was underpinned by two CBPR frameworks to develop a culturally tailored church-based lifestyle intervention to prevent diabetes and its complications in the Australian Samoan community. The name LTA, which means ‘a new dawn,’ was chosen by the community to signify a new dawn without diabetes in the Australian Samoan community. Strategies for engaging with the Australian Samoan community in South Western Sydney are discussed mapped to the key principles from the CBPR frameworks. In particular, this paper highlights the steps involved in building relationships with Samoan community leaders and the vital role of community activators and peer support facilitators in the success of delivering the program. Lessons learnt, such as the importance of church and maintaining a Samoan way of life in daily activities, and processes to build effective partnerships and maintain long-term relationships with the Australian Samoan community, are also discussed. Our paper, through providing a case example of how to apply CBPR frameworks, will help guide future community-based health promotion programs for underserved communities.

Barriers and Facilitators of Breast Cancer Screening amongst Culturally and Linguistically Diverse Women in South Western Sydney: A Qualitative Explorative Study

Breast cancer is the most common cause of cancer amongst Australian women and the second most common cause of cancer mortality. Despite the proven effectiveness of early intervention, screening rates remain subpar across many regions in New South Wales (NSW). Screening rates are particularly low within the culturally and linguistically diverse (CALD) area of South Western Sydney (SWS). The objective of this study was to qualitatively explore barriers and facilitators to breast screening from the perspectives of CALD women from SWS. CALD women aged ≥40 who resided in SWS were invited to participate in a semi-structured interview to explore barriers and facilitators to breast cancer screening. Interviews were recorded, transcribed verbatim and analysed thematically to identify recurring patterns in the data. Sixteen women from CALD backgrounds participated. Women in this study reported absence of symptoms, fatalistic beliefs and embarrassment during the procedure to be the primary reasons for reluctance to screen. Lack of general practitioner (GP) endorsement, transport issues and pain associated with the procedure were also reported as additional barriers to screening. Common facilitators to screening included encouragement from family and friends, family history of cancer and media adverts. CALD women have distinctive barriers to mammography, which lead to poor breast screening participation rates. Opportunistic health promotion in this area is warranted and may lead to better health outcomes amongst this population.

Use of complementary medicines and lifestyle approaches by people living with dementia: Exploring experiences, motivations and attitudes

BACKGROUND

Lack of effective treatments for chronic conditions is associated with high rates of complementary medicine (CM) use. However, little is known about CM use for dementia.

AIMS AND OBJECTIVES

The aim of this study was to explore the experiences, motivations, and attitudes towards CM use by people living with dementia in an Australian setting.

DESIGN

This study had a qualitative research design; quantitative demographic information was also collected.

METHODS

In-depth interviews were conducted with people living with dementia and their caregivers (N = 18). A thematic (inductive) analysis approach was taken to interpret data.

RESULTS

Three in four participants used CM for dementia, spending ~AUD$100/month (USD$70/month). Within three overarching themes, a range of sub-themes was identified: (1) CM knowledge and use: people living with dementia and caregivers understanding of CM, types of CM used, and CM usage patterns; (2) Self-determined reasons for use/non-use: maintain or improve quality of life, hope, management of dementia symptoms, level of awareness, willingness and evidence, perceptions on efficacy and safety of CM, experiences of conventional medicine, and holistic approach to wellness; (3) External determinants of use: information on CM, relationship influences on CM use, and experiences with General Practitioners (GPs) and CM.

CONCLUSION

Findings highlight that CM use is widespread and positively viewed by people living with dementia and their caregivers. Decisions regarding CM use were based on personal opinions. Findings have important implications for conversations with health professionals regarding CM use by people living with dementia to improve communication, health literacy, and reduce the risk of adverse effects through polypharmacy.

IMPLICATIONS FOR PRACTICE

This study showed that CM is a valued approach for dementia management by people living with dementia, their families, and healthcare providers. Future international research is required to evaluate the efficacy and safety of these approaches and promote accurate advice in nursing care.

"We need a one-stop-shop": co-creating the model of care for a multidisciplinary memory clinic with community members, GPs, aged care workers, service providers, and policy-makers

BACKGROUND

Timely diagnosis of dementia has a wide range of benefits including reduced hospital emergency department presentations, admissions and inpatient length of stay, and improved quality of life for patients and their carers by facilitating access to treatments that reduce symptoms, and allow time to plan for the future. Memory clinics can provide such services, however there is no 'gold standard' model of care. This study involved the co-creation of a model of care for a new multidisciplinary memory clinic with local community members, General Practitioners (GPs), policy-makers, community aged care workers, and service providers.

METHODS

Data collection comprised semi-structured interviews (N = 98) with 20 GPs, and three 2-h community forums involving 53 seniors and community/local government representatives, and 25 community healthcare workers. Interviews and community forums were audio-recorded, transcribed verbatim, and coded by thematic analysis using Quirkos.

RESULTS

GPs' attitudes towards their role in assessing people with dementia varied. Many GPs reported that they found it useful for patients to have a diagnosis of dementia, but required support from secondary care to make the diagnosis and assist with subsequent management. Community forum participants felt they had a good knowledge of available dementia resources and services, but noted that these were highly fragmented and needed to be easier to navigate for the patient/carer via a 'one-stop-shop' and the provision of a dementia key worker. Expectations for the services and features of a new memory clinic included diagnostic services, rapid referrals, case management, education, legal services, culturally sensitive and appropriate services, allied health, research participation opportunities, and clear communication with GPs. Participants described several barriers to memory clinic utilisation including transportation access, funding, awareness, and costs.

CONCLUSION

This study demonstrates the importance of working with stakeholders to co-design models of care for people with dementia that take into account the local communities' needs. Findings pave the way for the development of a potential new "gold standard" memory clinic model of care and operationalise new national clinical guidelines.

Outcomes of a church-based lifestyle intervention among Australian Samoans in Sydney - Le Taeao Afua diabetes prevention program

AIMS

To evaluate the effectiveness of a culturally adapted, church-based lifestyle intervention among Australian Samoans living in Sydney.

METHODS

This was a prospective, pre-post study of a church-wide education and support programme delivered by Community Coach Facilitators and Peer Support Facilitators to prevent, and promote self-management of, Type 2 diabetes. Participants completed questionnaires, anthropometric and HbA1c measurements before and 3-8 months after the intervention. The primary outcome was HbA1c.

RESULTS

Overall, 68/107(63.5%) participants completed both before and after intervention data collection (mean age 48.9 ± 14.2 years; 57.2% female). HbA1c dropped significantly between baseline and follow-up among participants with known diabetes (8.1 ± 2.4% (65 mmol/mol) vs 7.4 ± 1.8% (57 mmol/mol); p = 0.040) and non-significantly among participants with newly diagnosed diabetes (8.0 ± 2.1% (64 mmol/mol) vs 7.1 ± 2.3 (54 mmol/mol); p = 0.131). Participants with no diabetes increased their weekly moderate and vigorous physical activity (316.1 ± 291.6mins vs 562.4 ± 486.6mins; p = 0.007) and their diabetes knowledge also improved post-intervention (42.0 ± 13.5% to 61.3 ± 20.2%; p < 0.001). There were no significant reductions in blood pressure, BMI or waist circumference at follow-up.

CONCLUSIONS

A structured, church-based, culturally tailored lifestyle intervention showed a number of improvements in diabetes risk among Samoans in Sydney. The intervention however, requires a more rigorous testing in a larger randomised controlled trial over a longer time period.

The Lived Experience of Australian Women Living with Breast Cancer: A Meta-Synthesis

BACKGROUND

Breast cancer is the second most common cancer among Australian women. In 2019, an estimated
19,000 women in Australia were diagnosed with breast cancer, with around 3,058 women dying from the disease in the
same year. Although many qualitative studies published in Australia exist which examine breast cancer from various
perspectives, only limited literature is available which addresses Australian women's lived experience of breast cancer
from diagnosis, treatment and beyond.

METHOD

Meta-synthesis of qualitative studies. Participants who took part in
either semi-structured interviews or surveys with open-ended questions were included. A thematic synthesis analysis
approach was used.

RESULTS

Five themes and 13 sub themes emerged from the data analysis which illustrated the lived
experience of Australian women diagnosed with breast cancer. Emotional burden and women's response towards their
breast cancer diagnosis were key themes. Experience of decision- making , social distress, symptoms beyond changes
in their body, fertility considerations and their role as mothers were some of the challenges during their treatment.
Women coped and adjusted with these challenges through the support of their family, and healthcare providers. Women
developed greater empowerment by making their life choices after treatment. Life choices such as getting into a new
relationship was challenging for single women.

CONCLUSION

Although most women were emotionally supported
following their diagnosis, there are still areas where women could be better supported such as when having to break
the news of their breast cancer diagnosis to their children, provision of ongoing emotional support for caregivers of
women with breast cancer, providing constant emotional and informational support at the point of diagnosis and during
their treatment, tailoring treatments according to different stages of pregnancy, and discussion of fertility treatments
in timely manner by healthcare professionals.

Diabetes, its risk factors and readiness to change lifestyle behaviours among Australian Samoans living in Sydney: Baseline data for church-wide interventions

OBJECTIVES

To describe the current prevalence of type 2 diabetes (diabetes) and readiness to change diet and physical activity among Samoans associated with churches in Sydney.

METHODS

Residents aged ≥18 years attending four Samoan churches in Sydney were invited to participate in a church-wide lifestyle intervention. Participants completed questionnaires, anthropometric measurements, provided a non-fasting blood sample for HbA1c and random blood glucose (RBG) measurement, and performed a 6-minute walk test. Obesity was defined using a Pacific body mass index (BMI) threshold ≥32 kg/m² and diabetes if HbA1c was ≥6.5%.

RESULTS

In total, 131/187 (70%) of Samoans (mean age of 44.1 ± 15 years; Female 52%) participated. Diabetes was present in 33% of the population which included 20% previously diagnosed diabetes, duration 13.4 ± 6.7 years, (HbA1c 8.3 ± 2.5% and RBG 10.2 ± 4.1 mmol/L) and 13% had undiagnosed diabetes (HbA1c 8.1 ± 2.7% and RBG 10.3 ± 4.7 mmol/L). The overall baseline prevalence of obesity, high blood pressure and meeting the physical activity recommendation of ≥150 min/wk were 77%, 44% and 38% respectively. Over 90% of participants were contemplating, if not already taking action towards healthier diet choices and increasing physical activity.

CONCLUSIONS

Prevalence of diabetes and its risk factors were high among Samoans in Sydney with a high proportion with undiagnosed diabetes. SO WHAT?: These findings highlight the need to prioritise the delivery of culturally appropriate interventions tailored to the needs of the Samoan community. The high level of healthy lifestyle contemplation suggests that the community would be receptive to such interventions.

A Qualitative Exploration of Fijian Perceptions of Diabetes: Identifying Opportunities for Prevention and Management

Rates of diabetes are high in many communities of Pacific Island peoples, including people from Fiji. This qualitative study explores knowledge and attitudes towards diabetes among i-Taukei Fijians to facilitate the cultural tailoring of diabetes prevention and management programs for this community. Fijians aged 26 to 71 years (n = 15), residing in Australia, participated in semi-structured interviews; 53% (n = 8) were male. Interviews were audio-recorded, transcribed verbatim, then thematically analyzed. Diabetes is recognized as an important and increasing health problem requiring action in the i-Taukei Fijian community. Widespread support for culturally appropriate lifestyle interventions utilizing existing societal structures, like family networks and church groups, was apparent. These structures were also seen as a crucial motivator for health action. Intervention content suggestions included diabetes risk awareness and education, as well as skills development to improve lifestyle behaviors. Leveraging existing social structures and both faith and family experiences of diabetes within the Fijian community may help convert increased awareness and understanding into lifestyle change. Ongoing in-community support to prevent and manage diabetes was also regarded as important. We recommend building upon experience from prior community-based interventions in other high-risk populations, alongside our findings, to assist in developing tailored diabetes programs for Fijians.

Lifestyle Interventions for People with, and at Risk of Type 2 Diabetes in Polynesian Communities: A Systematic Review and Meta-Analysis

There is evidence that lifestyle intervention among Polynesian people can reduce diabetes incidence and complications, but this evidence has not been systematically reviewed. The aim of this study was to systematically review the efficacy of lifestyle interventions, targeting the prevention and management of type 2 diabetes among Polynesian people. MEDLINE, Web of Science, Cochrane Library, and Embase were searched to find randomised controlled trials (RCTs) and pre-post studies. Eight studies (four RCTs and four pre-post studies) with 1590 participants met the inclusion criteria. The data on health outcomes that was reported in these studies included blood pressure, body mass index, waist circumference, weight, and glycated haemoglobin (HbA1c). The meta-analyses showed that the interventions had resulted in statistically significant reductions in systolic blood pressure (SBP) across four of the studies (WMD, −9.93 mmHg; 95% Cl, −10.77 to −9.09; and p < 0.00001). However, the effects on weight across five of the studies (WMD, −1.15 kg; 95% Cl, −2.80 to 0.51; p = 0.18) and the HbA1c levels across two of the studies (WMD, −0.38%; 95% Cl, −1.15 to 0.39; and p = 0.33) were not statistically significant. This review provides evidence that lifestyle interventions may be effective in achieving modest reductions in SBP in Polynesian people. Further research is needed to fully assess the effectiveness of these interventions in this population long-term.

Psychosocial morbidity in TP53 mutation carriers: is whole-body cancer screening beneficial?

Germline TP53 mutation carriers are at high risk of developing a range of cancers. Effective cancer risk management is an important issue for these individuals. We assessed the psychosocial impact in TP53 mutation carriers of WB-MRI screening as part of the Surveillance in Multi-Organ Cancer (SMOC+) protocol, measuring their unmet needs, anxiety and depression levels as well as cancer worry using psychological questionnaires and in-depth interviews about their experiences of screening. We present preliminary psychosocial findings from 17 participants during their first 12 months on the trial. We found a significant reduction in participants' mean anxiety from baseline to two weeks post WB-MRI (1.2, 95% CI 0.17 to 2.23 p = 0.025), indicative of some benefit. Emerging qualitative themes show most participants are emotionally supported and contained by the screening program and are motivated by their immediate concern about staying alive, despite being informed about the current lack of evidence around efficacy of screening for people with TP53 mutations in terms of cancer morbidity or mortality. For those that do gain emotional reassurance from participating in the screening study, feelings of abandonment by the research team are a risk when the study ends. For others, screening was seen as a burden, consistent with the relentless nature of cancer risk associated with Li-Fraumeni syndrome, though these patients still declared they wished to participate due to their concern with staying alive. Families with TP53 mutations need ongoing support due to the impact on the whole family system. These findings suggest a comprehensive multi-organ screening program for people with TP53 mutations provides psychological benefit independent of an impact on cancer morbidity and mortality associated with the syndrome. The benefits of a multi-organ screening program will be greater still if the screening tests additionally reduce the cancer morbidity and mortality associated with the syndrome. These findings may also inform the care of individuals and families with other multi-organ cancer predisposition syndromes.

A systematic review of health promotion intervention studies in the police force: study characteristics, intervention design and impacts on health

To systematically review studies of health promotion intervention in the police force. Four databases were searched for articles reporting on prepost single and multigroup studies in police officers and trainees. Data were extracted and bias assessed to evaluate study characteristics, intervention design and the impact of interventions on health. Database searching identified 25 articles reporting on 21 studies relevant to the aims of this review. Few studies (n=3) were of long duration (≥6 months). Nine of 21 studies evaluated structured physical activity and/or diet programmes only, 5 studies used education and behaviour change support-only interventions, 5 combined structured programmes with education and behaviour change support, and 2 studies used computer prompts to minimise sedentary behaviour. A wide array of lifestyle behaviour and health outcomes was measured, with 11/13 multigroup and 8/8 single-group studies reporting beneficial impacts on outcomes. High risk of bias was evident across most studies. In those with the lowest risk of bias (n=2), a large effect on blood pressure and small effects on diet, sleep quality, stress and tobacco use, were reported. Health promotion interventions can impact beneficially on health of the police force, particularly blood pressure, diet, sleep, stress and tobacco use. Limited reporting made comparison of findings challenging. Combined structured programmes with education and behaviour change support and programmes including peer support resulted in the most impact on health-related outcomes.

Development and validation of measures to evaluate adolescents' knowledge about human papillomavirus (HPV), involvement in HPV vaccine decision-making, self-efficacy to receive the vaccine and fear and anxiety

OBJECTIVES

We describe the development and validation of measures of human papillomavirus (HPV)/HPV vaccination knowledge, fear/anxiety about vaccination, involvement in HPV vaccine decision-making, and self-efficacy with regard to getting the vaccine, designed to evaluate the efficacy of an intervention to affect these domains (collectively termed the HAVIQ: HPV Adolescent Vaccine Intervention Questionnaire).

STUDY DESIGN

Literature search, cognitive interviews and cross-sectional survey.

METHODS

A literature search identified existing items that were modified for the present measures. Experts reviewed draft measures for face and content validity. Cognitive interviews with adolescents were also used to assess content validity. Adolescents completed the measures and an internal reliability analysis of each measure was performed.

RESULTS

The four experts concurred that the measures had face validity. Cognitive interviews identified items requiring refinement. Content validity was examined with ten experts and was deemed acceptable. There were 1800 adolescents who completed the measures; Cronbach's alpha was >0.6 for three of the four measures. The four final measures are brief, comprising 25 items in total.

CONCLUSIONS

The measures are robustly developed and validity-tested. The HAVIQ may be used in research settings to evaluate adolescents' knowledge and experiences of the process of HPV vaccination in a school-based vaccination programme.

Timing and context: important considerations in the return of genetic results to research participants

General consensus exists that clinically significant germline genetic research results should be fed back to research participants. A body of literature is emerging about Australian research participants' experiences of feedback of genetic research results and factors that influence a participant's actions after receiving such information. This exploratory qualitative study conducted interviews with 11 participants from the International Sarcoma Kindred Study, four probands and seven of their relatives. They had been informed by letter of the availability of clinically significant germline TP53 mutations identified through research. We examined the participants' views about the feedback of these genetic test results. Thematic (inductive) analysis was used to analyse the data. A number of factors influenced participants' responses following notification. This included participants' understanding of the notification letter and their perception of the relevance of the information for them and/or their family. Most notably, timing of the letter in the context of an individual's current life experiences was important. Timing and context are novel factors identified that may impact on research participants' understanding or their ability to access clinically significant research results. We outline strategies for disseminating results to research participants and their next of kin that may reduce their uncertainty around the receipt of research results.

Li-Fraumeni syndrome: cancer risk assessment and clinical management

Carriers of germline mutations in the TP53 gene, encoding the cell-cycle regulator and tumour suppressor p53, have a markedly increased risk of cancer-related morbidity and mortality during both childhood and adulthood, and thus require appropriate and effective cancer risk management. However, the predisposition of such patients to multiorgan tumorigenesis presents a specific challenge for cancer risk management programmes. Herein, we review the clinical implications of germline mutations in TP53 and the evidence for cancer screening and prevention strategies in individuals carrying such mutations, as well as examining the potential psychosocial implications of lifelong management for a ubiquitous cancer risk. In addition, we propose an evidence-based framework for the clinical management of TP53 mutation carriers and provide a platform for addressing the management of other cancer predisposition syndromes that can affect multiple organs.

Hemoglobin switching in Rana/Xenopus erythroid heterokaryons: factors mediating the metamorphic hemoglobin switch are conserved

Hemoglobin switching, which occurs in all classes of vertebrates as well as in certain invertebrates, is due to developmental regulation of different globin genes which are typically arranged in clustered families. By fusing erythroid cells of different developmental programs, trans-acting factors that regulate this switch in gene expression have been detected [Ramseyer et al. (1989): Dev Biol 133:262-271]. Adult erythroid cells of one anuran species, Xenopus laevis, were fused with tadpole erythroid cells of another frog, Rana catesbeiana, creating developmental erythroid heterokaryons that synthesize adult Rana globin mRNA and hemoglobins. The results show that factors from adult Xenopus erythroid cells are capable of inducing adult Rana globin gene expression in the Rana tadpole erythroid cell nucleus. We have used the cross-induction of adult Rana hemoglobin synthesis in these adult Xenopus/Rana tadpole erythroid heterokaryons to address two practical questions, answers to which may be helpful in isolating developmental stage-specific globin gene regulatory proteins: 1) Are erythroblasts which are actively expressing globin mRNAs and hemoglobins richer in specific globin-inducing activities than other stages of erythroid cellular differentiation? 2) Do mature, circulating erythrocytes still have the activities necessary to mediate the cross-induction of Hb synthesis? The results reported here show that the answers to both questions are affirmative and show that quiescent, fully differentiated adult erythroid cells are still capable of expressing the trans-activator(s). These findings show that factors which mediate the metamorphic hemoglobin switch are conserved between these two genera of frogs.

Intracellular signals for developmental hemoglobin switching

We have detected trans-acting factors that regulate developmental hemoglobin switching by fusing erythroid cells of different developmental programs. Adult erythroid cells of one anuran species, Xenopus laevis, were fused with tadpole erythroid cells of another frog, Rana catesbeiana. In a second set of experiments, dimethyl sulfoxide-induced murine erythroleukemia cells, which express only adult mouse globins, were fused with Rana tadpole erythroid cells, which express only embryonic and fetal-like globins. Adult Rana globin gene expression was detected in both sets of transient heterokaryons at 6 hr after fusion. Dot blots and Northern blots of total RNA from the heterokaryons contained material that reacted with an adult Rana alpha-globin probe; newly synthesized adult Rana hemoglobin tetramers were detected with native polyacrylamide gel electrophoresis. These results show that developmental stage-specific transacting factors for globin genes can function across vertebrate classes (mammalia to amphibia) and suggest that the mechanisms that regulate developmental hemoglobin switching are highly conserved.

Formation of transient polykaryons by fusion of erythrocytes of different developmental programs

We report here two methods of fusing erythroid cells from bullfrogs (Rana catesbeiana), using polyethylene glycol or calcium phosphate, which yield masses of polykaryons in which the cytoplasms and nuclei of tadpole and adult frog erythroid cells are intermixed. The masses of fused cells carry out protein synthesis in culture, including the assembly of normal hemoglobin (Hb) tetramers. In these polykaryons there is reactivation of the expression of specific Hbs that have previously been "turned off" in vivo as the result of either a developmental Hb switch or normal cellular differentiation and RBC maturation. For example, the products of fusion of tadpole erythroblasts with adult frog mature RBCs synthesize adult Hb, whereas neither cell population alone does so. Recent experiments have taken advantage of a Hb-expression polymorphism that we discovered in this species, such that some tadpoles have greatly reduced expression of one of the larval Hbs (Hb Td-4). Fusion of erythroblasts from such tadpoles with RBC from frogs that had expressed Hb Td-4 when they were tadpoles produces polykaryons that synthesize Hb Td-4, indicating there is a trans factor that stimulates Td-4 expression. Heterospecific erythroid cell polykaryons can be constructed in an analogous manner, facilitating the study of trans-acting factors that regulate specific globin gene expression during development.

Management of combined segment disease

Eighty-five of 148 inflow procedures were performed for combined segment disease. Our study shows that aortofemoral bypass is clinically and functionally superior to axillofemoral bypass in limbs with combined segment disease and hemodynamic criteria for limb salvage. The results of these two procedures are comparable for claudicant limbs. A derivative of segmental plethysmography, the predictive index, can select preoperatively those limbs that will fail to respond to aortofemoral bypass alone. Finally, either in limbs selected for aortofemoral bypass with both ischemic tissue lesions and a predictive index greater than 0.2 or in limbs selected for axillofemoral bypass with ischemic tissue lesions alone, a synchronous procedure can be performed with relatively low morbidity and excellent early functional results.