Rural longitudinal integrated clerkships and medical workforce outcomes: A scoping review

INTRODUCTION

Internationally the medical workforce is suffering from a persistent geographic and specialist maldistribution. Longitudinal models of rural medical education such as longitudinal integrated clerkships (LIC) have been one of the strategies employed to redress this issue.

AIM

To map and synthesise the evidence on the medical workforce outcomes of rural LIC graduates, identifying gaps in the literature to inform future research.

METHODS

This review followed Arksey and O'Malley's methodological steps. Databases searched included Medline, CINAHL Complete (EBSCOhost), Scopus, Embase (Elsevier), and ISI Web of Science.

RESULTS

A total of 9045 non-duplicate articles were located, 112 underwent a full review, with 25 articles meeting the inclusion criteria. Studies were commonly cohort-based (84%), with data collected by database tracking and data linkage (52%). Five themes were identified to summarise the studies: (i) Overall geographic workforce outcomes (ii) influence of non-LIC medical training, (iii) remaining in region and level of rurality, (iv) medical speciality choice and rurality, and (v) selection and preferences.

CONCLUSION

Synthesis of the evidence related to workforce outcomes of rural LIC graduates provides directions for future rural medical workforce planning and research. While rural LIC graduates were found to be more likely to work rurally and in primary care specialities compared to graduates from other training pathways there is evidence to suggest this can be enhanced by strategically aligning selection and training factors.

If you build it who will come? Case mix data of a new rural paediatric outpatient clinic

INTRODUCTION

There is limited current evidence describing the case mix data of rural paediatric outpatient clinics. Collection and analysis of this data is essential for health service planning, facilitating the identification of areas of need within specific communities to support contextualised delivery of paediatric health care.

OBJECTIVE

To describe the case mix of patients seen during the initial 12 months of a rural paediatric service, providing evidence to inform rural health service planning.

DESIGN

A retrospective cohort study.

RESULTS

There were 149 initial consultations during the study period. Behavioural/developmental problems were found in 71.8% of patients and physical problems were present in 64.4% of patients. This resulted in 38.9% of patients having a combination of problem types. 42.9% of patients were referred to or already accessing allied health services, while 20% were accessing specialised paediatric support services such as the National Disability Insurance Scheme and child protection services. Investigations were ordered for 45% of patients, with medications prescribed in 43% of cases. Only 5.4% of patients were discharged after their initial appointment. There were significant differences in problems identified on the referral compared to at the initial appointment demonstrating the value of this service to a rural community.

CONCLUSION

The case mix data illustrates a rural paediatric cohort with a complex and chronic burden of disease especially in terms of behavioural and developmental problems. These findings add to the literature on rural paediatric patient care and demonstrate the value of an embedded paediatric service in a medium sized rural town.

A case study of a novel longitudinal rural internship program

INTRODUCTION

Rural medical training along all components of the medical training continuum has been shown to enhance rural workforce outcomes. However, due to the maldistribution of the Australian medical workforce, health services of increased rurality are limited in their ability to fulfil the supervision requirements for all levels of trainees, especially junior doctor training. Although longitudinal program design and pedagogy has flourished in medical school education through the Longitudinal Integrated Clerkship model, this has not yet been widely translated to prevocational training. This study describes how a longitudinal program design was conceptualised and implemented within a rural health service to create a novel internship program.

METHODS

A descriptive case study methodology was employed to describe and evaluate the longitudinal integrated internship program. Relevant program documents such as rosters and accreditation submissions were reviewed to aid in describing the program. Interviews with participants involved in the program were conducted during the middle (May) and end (November) points of the program's first year (2021) to investigate perspectives and experiences of the internship model.

RESULTS

Each week, interns were rostered for 1 day in the hospital's emergency department and 3 days in general surgery or general medicine, swapping disciplines after 6 months. In this way, interns completed core rotations longitudinally, meeting accreditation and supervision requirements. Additionally, 1 day per week was spent parallel consulting in general practice. Participants described program enablers as the organisational vision and staff buy-in, as well as the longitudinal attachments to disciplines. Barriers identified were the tenuous nature of the medical workforce and long-term sustainability of the program. Benefits of the program included value-adding and preparedness for practice, particularly in a rural context.

CONCLUSION

Intern programs that meet the accreditation, supervision and learning requirements can be successfully delivered at rural health services through longitudinal models of medical education. As the intern year is a key component of the rural generalist training pathway, development of similar innovative models provides the opportunity for rural communities to grow their own future medical workforce.

Referral and triage patterns of a new rural paediatric outpatient service in south-western Victoria, Australia

INTRODUCTION

There is limited available information describing referral and triage patterns for rural paediatric outpatient clinics to guide health service planning and delivery. To address this, referrals for all new patients who attended an appointment during the initial year of a new rural paediatric outpatient service in Portland, Victoria, Australia were examined.

METHODS

This was a retrospective review of referrals with initial consultations between 29 October 2018 and 28 October 2019.

RESULTS

A total of 149 referrals for new patients were received, equating to a referral rate of 31.6 referrals per 1000 children for the service's Local Government Area (LGA). A total of 65.1% of new patients had not previously engaged with a paediatric service. Overall, 66.6% of referrals were triaged as having a behavioural or developmental problem. The median time from referral letter to initial appointment was 63 days, with referrals that were triaged as behavioural or developmental having an average wait time of 86 days until initial appointment.

CONCLUSION

The establishment of this new rural paediatric service showed a latent need within the service's LGA, as demonstrated by higher referral rates compared to previously published studies and a majority patient population who had not previously accessed paediatric services. The greatest area of need identified by referral analysis was for behavioural and developmental problems.

Impact of the COVID-19 pandemic on student experiences during rural placements in Australia: findings from a national multi-centre survey

BACKGROUND

The aim of this national study was to explore the learning experiences of Australia's medical students who trained rurally during the COVID-19 pandemic in 2020.

METHODS

A cross-sectional, national multi-centre survey was conducted in 2020, through the Federation of Rural Australian Medical Educators (FRAME). Participants were medical students who had completed an extended Rural Clinical School (RCS) training placement (≥ 12 months). A bespoke set of COVID-19 impact questions were incorporated into the annual FRAME survey, to capture COVID-19-related student experiences in 2020. Pre-pandemic (2019 FRAME survey data) comparisons were also explored.

RESULTS

FRAME survey data were obtained from 464 students in 2020 (51.7% response rate), compared with available data from 668 students in 2019 (75.6% response rate). Most students expressed concern regarding the pandemic's impact on the quality of their learning (80%) or missed clinical learning (58%); however, students reported being well-supported by the various learning and support strategies implemented by the RCSs across Australia. Notably, comparisons to pre-pandemic (2019) participants of the general RCS experience found higher levels of student support (strongly agree 58.9% vs 42.4%, p < 0.001) and wellbeing (strongly agree 49.6% vs 42.4%, p = 0.008) amongst the 2020 participants. Students with more than one year of RCS experience compared to one RCS year felt better supported with clinical skills learning opportunities (p = 0.015) and less affected by COVID-19 in their exam performance (p = 0.009).

CONCLUSIONS

This study has provided evidence of both the level of concern relating to learning quality as well as the positive impact of the various learning and support strategies implemented by the RCSs during the pandemic in 2020. RCSs should further evaluate the strategies implemented to identify those that are worth sustaining into the post-pandemic period.

Rural longitudinal integrated clerkships and medical workforce outcomes: a scoping review protocol

INTRODUCTION

The shortage of doctors in rural locations is an international problem, contributing to limited access to healthcare and a health disparity between rural and metropolitan populations. To encourage additional doctors to work in rural locations, more doctors than ever are being trained in rural settings. One rural clerkship model that is gaining recognition for fostering rural careers is the Longitudinal Integrated Clerkship. Longitudinal Integrated Clerkship programmes vary in terms of settings and durations, but at their core have the fundamental commonality of continuity, with students learning the curriculum in an integrated manner. The scoping review will synthesise the literature pertaining to medical workforce outcomes of rural Longitudinal Integrated Clerkship programmes, to uncover areas that require further research and establish elements of medical education programme design that positively influence rural workforce outcomes.

METHODS AND ANALYSIS

The review will follow Arksey and O'Malley's six step scoping review framework. MEDLINE, CINAHL complete (EBSCOhost), Scopus, Embase (Elsevier) and ISI Web of Science databases will be searched along with Google, Google Scholar, ProQuest and WHO library database. Single design studies examining the geographic work locations and/or medical specialty of rural Longitudinal Integrated Clerkship graduates will be included. Data from quantitative and mixed-methods studies will be included. Only studies written in English will be included. There will be no date range restriction imposed on the reviewed studies. Two reviewers will independently screen and critically appraise the articles to determine if they meet the inclusion criteria. Data from eligible studies will be extracted for synthesis.

ETHICS AND DISSEMINATION

Scoping reviews do not require ethics approval. Results will be submitted to a peer-reviewed journal and may be presented at relevant conferences. The findings will also be shared within the Longitudinal Integrated Clerkship community of medical educators.

Levocarnitine supplementation for management of hypertriglyceridemia in patients receiving parenteral nutrition

BACKGROUND

Levocarnitine deficiency has been observed in patients receiving parenteral nutrition (PN) and can cause or worsen hypertriglyceridemia. The objective was to characterize use of levocarnitine supplementation in PN and evaluate its effect on triglyceride levels in hospitalized adults.

METHODS

This retrospective, single-center study included patients with triglyceride levels ≥175 mg/dl while receiving PN who had a subsequent reduction in lipid injectable emulsion dose. A piecewise linear regression was used to evaluate trends in triglyceride levels before and after the intervention, defined as initiation of levocarnitine in PN for the levocarnitine group, or reduction in lipid injectable emulsion alone for the control group.

RESULTS

Two hundred sixty-one patients who received PN had an elevated triglyceride level and lipid injectable emulsion dose reduction, of which 97 (37.2%) received levocarnitine in PN. The median (IQR) levocarnitine dose added to PN was 8.0 (5.7-9.9) mg/kg. Triglyceride levels at 30 days post-intervention did not differ between groups (125 vs 176 mg/dl, P = .345). The addition of levocarnitine to PN was associated with a significantly greater rate of reduction in triglyceride levels pre-intervention to post-intervention compared with a reduction in lipid injectable emulsion alone (-11 vs -3 mg/dl per day; 95% CI, -15 to -2; P = .012).

CONCLUSION

In hospitalized adults with hypertriglyceridemia who had a lipid injectable emulsion dose reduction, the addition of levocarnitine in PN was not associated with a difference in triglyceride levels at 30 days; however, a greater rate of improvement in pre-intervention to post-intervention triglyceride levels was observed.

Graduate rural work outcomes of the first 8 years of a medical school: What can we learn about student selection and clinical school training pathways?

OBJECTIVE

To determine the student characteristics and clinical school training pathways that are associated with postgraduate rural practice.

DESIGN

A cross-sectional observational study.

SETTING

Deakin University's School of Medicine, encompassing 3 rural and 2 metropolitan clinical schools, including a rural longitudinal integrated clerkship (LIC) year.

PARTICIPANTS

A total of 948 School of Medicine medical graduates (2011-2018) who had an Australian Health Practitioners Regulation Agency registered work location in Australia (September 2019).

MAIN OUTCOME MEASURE(S)

Graduates' work locations were linked with admission and clinical school training data and analysed for significant associations.

RESULTS

Graduates completing a rural LIC year and a regional rural clinical school year were 7 times more likely to be working rurally than metropolitan trainees. A small number of rural background (RB) students completed a rural LIC and rural clinical school year, 66.7% of whom were practising rurally. Further associations with rural practice were attending a rural clinical school for 2 years or a rural LIC for 1 year, student having a RB, rurally bonded course placement and being an international student.

CONCLUSION

The significant influence of a rural LIC year on graduate rural work location is noteworthy, especially when undertaken by students from a RB in combination with a second regional rural clinical school year. These findings support the strategic alignment of rural student selection with rural clinical school training pathways to achieve the greatest impact on rural graduate workforce outcomes.

The impact of clerkship model and clinical setting on medical student's participation in the clinical workplace: A comparison of rural LIC and rural block rotation experience

PURPOSE

To compare the participation of rural Longitudinal Integrated Clerkship (LIC) and rural Block Rotation (BR) students in surgical clinical activities.

METHODS

Third-year medical students from Deakin University's Rural Clinical Schools were invited to record their participation during clinical encounters with ten common surgical conditions, using a descriptive five-point progressive entrustment scale. Participation levels of LIC and BR students were compared for differences, according to clinical task and context.

RESULTS

LIC students recorded greater active participation across all clinical tasks.Highest levels of active participation occurred in General Practice, a setting only LIC students were exposed to at this course stage. BR students recorded the majority of their surgical encounters in the hospital inpatient setting, where their involvement was predominantly observational. Both groups recorded high levels of participation in the Emergency Department.

CONCLUSIONS

Active participation in clinical encounters with surgical patients was enhanced by participation in a LIC program and cannot be attributed to the rural context alone. Student participation is influenced by clinical context, presenting the opportunity to reconsider the design of clerkships to include models that facilitate active student participation. Further research is required to investigate the learner, supervisor and contextual factors influencing entrustment decisions within clerkships.

Medical Students Can Learn Surgery Effectively in a Rural Longitudinal Integrated Clerkship

BACKGROUND

At Deakin University School of Medicine, compulsory formal teaching in Surgery occurs in year 3. This may occur as part of a rural longitudinal integrated clerkship (LIC), or in a traditional teaching hospital block rotation (BR). The purpose of this study was to compare these groups' exposure to surgical common conditions and their academic outcomes.

METHODS

Part I: This was a survey of students' encounters with patients with common surgical conditions between 2016 and 2018. Self-reported data were collected describing the nature of the encounters and their clinical settings. Part II: All third year Surgery MCQ and OSCE results from 2011 to 2017 were analyzed. Students were deidentified and grouped according to whether they were in the LIC or BR programme.

RESULTS

Part I: Thirty-eight third year students (20 LIC, 18 BR) submitted data for a total of 188 clinical encounters. Both groups encountered all nominated common surgical conditions, but the settings in which this occurred were different. BR students saw most patients as hospital inpatients whereas LIC student encounters were distributed across multiple clinical sites. Part II: A total of 942 (121 [26%] LIC and 821 [74%] BR) students' assessment results were analyzed. The groups performed similarly in the MCQ (p = 0.21) and OSCE (p = 0.16) examinations.

CONCLUSIONS

Students who were taught surgery in a LIC program performed similarly to on their final exams to their peers in traditional clerkships, with self-reported student data indicating both groups encountered a similar range of conditions.

Safety of thoracic radiotherapy in patients with prior immune-related adverse events from immune checkpoint inhibitors

BACKGROUND

Immune checkpoint inhibitors (ICIs) and thoracic radiotherapy are increasingly used to treat advanced cancers. Despite data indicating exaggerated radiation toxicities in patients with autoimmune disease, the safety of thoracic radiotherapy in patients with prior ICI-associated immune-related adverse events (irAEs) is undefined.

PATIENTS AND METHODS

Patients treated from 2014 to 2020 with ICIs were queried for receipt of corticosteroids and radiotherapy. Patients who received thoracic radiation after symptomatic irAEs were assessed for ≥grade 2 radiation pneumonitis (RP). Characteristics predictive of RP were assessed using logistic regression and response relationships were modeled.

RESULTS

Among 496 assessed patients, 41 with irAE history subsequently treated with thoracic radiotherapy were analyzed. Most irAEs were grade 2 (n = 21) and 3 (n = 19). Median time from irAE onset to radiotherapy was 8.1 months. Most patients received stereotactic body radiation therapy (n = 20) or hypofractionated radiotherapy (n = 18). In total, 25 patients (61%) developed ≥grade 2 RP at a median of 4 months from radiotherapy and 11 months from onset of irAEs. Three months from RP onset, 16 of 24 (67%) assessable patients had persistent symptoms. Among patients with prior ICI pneumonitis (n = 6), five patients (83%) developed ≥grade 2 RP (grade 2, n = 3; grade ≥3, n = 2). The mean lung radiation dose (MLD) predicted for RP (odds ratio: 1.60, P = 0.00002). The relationship between MLD and RP was strong (area under the receiver-operating characteristic curve: 0.85) and showed an exaggerated dose-response. Among patients with an MLD >5 Gy (n = 26), 21 patients (81%) developed ≥grade 2 RP.

CONCLUSION

This is the first study assessing the toxicity of radiotherapy among patients with prior irAEs from ICIs. Patients with prior irAEs were found to be at very high risk for clinically significant and persistent RP from thoracic radiotherapy. Careful consideration should be given to the possibility of an increased risk of RP, and close monitoring is recommended in these patients.

'It could have been a lot worse': the psychological effects of farm-related serious injury in Victoria

INTRODUCTION

The psychological response to injury is an important factor in recovery, and the development of psychological problems can result in a delay or inability to return to pre-injury function, including return to work. Farming is widely acknowledged as a stressful occupation, with non-injured farmers already at an increased risk of developing significant psychological problems, including high levels of stress and depression, and increased rates of suicide. This study aimed to investigate the psychological effects of serious farm-related injury on farmers, and how this influences their recovery.

METHODS

This was a qualitative study of 31 farmers in the state of Victoria, Australia, who sustained major trauma between 2007 and 2013. Participants were identified using the Victorian State Trauma Registry and underwent an in-depth, semi-structured telephone interview. Recruitment continued until data saturation was achieved, and thematic analysis was used to identify important themes from the data.

RESULTS

For many farmers, the traumatic circumstances and ongoing impact of their injury are life-changing. In this study, the psychological effects of sustaining a major farm-related injury varied between participants; however, four major interconnected themes were identified: importance of a pragmatic outlook; grief, helplessness and loss of independence; traumatic thoughts post-injury; and the importance of the support network and community. The findings of this study highlight both a reluctance for psychological assistance as well as the importance of psychological resilience and support networks to recovery.

CONCLUSION

Overall, a positive outlook was found to be the primary enabler in the farmers' recovery. It is recommended that injured farmers should be provided with additional psychological support and advice to aid in their recovery. Additionally, psychological support services should be extended to include both the family network and the broader farming community, as these were found to experience significant short- and long-term stress following farmers' injury.

The role of vertically integrated learning in a rural longitudinal integrated clerkship

BACKGROUND

Deakin's Rural Community Clinical School (RCCS) is a Longitudinal Integrated Clerkship (LIC) program in Western Victoria. Students undertake a year-long placement in a rural General Practice, many of which also host General Practice Registrars. There is a lack of evidence addressing the role and impact of Vertically Integrated Learning (VI) in practices hosting both LIC medical students and General Practice Registrars. The objective of the study was to establish how VI is perceived in the LIC context and the impact that it has on both learners and practices, in order to consider how to potentiate the role it can play in facilitating learning.

METHODS

Semi-structured, in-depth, qualitative interviews were undertaken, with 15 participants located in RCCS General Practices. Emergent themes were identified by thematic analysis.

RESULTS

Five main interconnected themes were identified; (i) understanding and structure, (ii) planning and evaluation, (iii) benefits, (iv) facilitators, and (v) barriers.

CONCLUSION

VI in a rural LIC is not clearly understood, even by participants. VI structure and methodology varied considerably between practices. Benefits included satisfying and efficient sharing of knowledge between learners at different levels. VI was facilitated by the supportive and collegiate environment identified as being present in a rural LIC context. Resources for VI are needed to guide content and expectations across the continuum of medical training and evaluate its role. The financial impact of VI in a rural LIC warrants further exploration.

What Happens to the Farm? Australian Farmers' Experiences after a Serious Farm Injury

OBJECTIVES

To investigate the experiences of farmers on returning to farming following a serious farm-related injury.

METHODS

Patients who had sustained major trauma on a farm in Victoria, Australia, were identified using the Victorian State Trauma Registry (VSTR). In depth, semistructured phone interviews were conducted with 31 participants. Interview data were subjected to thematic analysis to identify important recurring themes. Interviews continued until data saturation was achieved.

RESULTS

Interviewees included self-employed full-time farmers, part-time farmers with a supplementary income, and agricultural employees. Analysis of participant responses connected to returning to farming after a serious farm-related injury identified five major interconnected themes: (i) effect on farm work, (ii) farming future, (iii) safety advocacy, (iv) changes to farming practices, and (v) financial ramifications.

CONCLUSION

Farmers who have sustained a serious farm-related injury are an important resource; their experiences and perspectives could assist in the development of educational and transitional support services from recovery back to working at a preinjury level, while ensuring farming production is sustainable during this period. Furthermore, farm safety programs can be enhanced by the engagement of farmers, such as participants in this study as advocates for improved farm safety practices.

Response of Femoral Venous Oxygen Tension to Graduated Pressure Stockings - Possible Relationship to Deep Vein Thrombosis

Venous oxygen tension (pO2) was measured in discrete samples of blood obtained through the femoral vein of cardiac catheterisation patients before, during and after application of sustained external graduated pressure in the form of compression stockings (T. E. D. Kendall). There was a significant reduction (p <0.05) of pO2 from the baseline value both 30 sec and one minute after the application of the pressure stockings. Thereafter, the pO2 rose to baseline values. Two minutes after the stockings were removed there was again a significant reduction (p <0.05) of pO2 from the baseline value. We suggest that the decrease in ivenous pO2 on application of external pressure may be a reflection of washing out of stagnant hypoxic blood from the venous valve pockets, which may be related to the formation of deep vein thrombosis (DVT).

Lifestyle risk factors and corresponding levels of clinical advice and counselling in general practice

BACKGROUND

The objective of this study was to examine prevalence rates of lifestyle risk factors in the Western Victorian Primary Health Network (WV PHN) general practice patient population and the corresponding levels of clinical advice and counselling.

METHODS

Analysed data from the Bettering the Evaluation and Care of Health (BEACH) program from April 2011 to March 2015 were examined, providing a comparison of three geographical areas of general practice patients: WV PHN, Victoria and Australia.

RESULTS

Rates of clinical advice and counselling for diet and exercise provided by general practitioners (GPs) in the WV PHN network were significantly lower than Victorian and Australian rates, despite the region's higher obesity rates. Smoking rates were higher in the WV PHN compared with Australia, but there was no difference in the levels of smoking cessation advice disseminated. Across all regions, one in four patients drank alcohol at hazardous levels.

DISCUSSION

GPs in rural practice require further support, encouragement and resources to provide diet and exercise advice to their patients more frequently.

Role of insulin-like growth factor binding proteins in mammary gland development

Insulin-like growth factors (IGFs) play an important role in mammary gland development and their effects are, in turn, influenced by a family of 6 IGF-binding proteins (IGFBPs). The IGFBPs are expressed in time- and tissue-specific fashion during the periods of rapid growth and involution of the mammary gland. The precise roles of these proteins in vivo have, however, been difficult to determine. This review examines the indirect evidence (evolution, chromosomal location and roles in lower life-forms) the evidence from in vitro studies and the attempts to examine their roles in vivo, using IGFBP-deficient and over-expression models. Evidence exists for a role of the IGFBPs in inhibition of the survival effects of IGFs as well as in IGF-enhancing effects from in vitro studies. The location of the IGFBPs, often associated with the extracellular matrix, suggests roles as a reservoir of IGFs or as a potential barrier, restricting access of IGFs to distinct cellular compartments. We also discuss the relative importance of IGF-dependent versus IGF-independent effects. IGF-independent effects include nuclear localization, activation of proteases and interaction with a variety of extracellular matrix and cell surface proteins. Finally, we examine the increasing evidence for the IGFBPs to be considered as part of a larger family of extracellular matrix proteins involved in morphogenesis and tissue re-modeling.

Inverse changes in fetal insulin-like growth factor (IGF)-1 and IGF binding protein-1 in association with higher birth weight in maternal diabetes

OBJECTIVE

The insulin like growth factor (IGF) system plays a key role in regulating fetal growth, is metabolically regulated, and may influence development of increased birth weight in offspring of mothers with diabetes. We examined IGF-1 and IGF binding protein-1 (IGFBP-1) concentrations in cord blood samples from offspring of mothers with gestational and type 2 diabetes.

DESIGN AND PATIENTS

Case-control study of Maori and Pacific Island mothers recruited prospectively at Middlemore Hospital, South Auckland, New Zealand.

MEASUREMENTS

Cord blood (for insulin, IGF-1 and IGFBP-1) was taken from umbilical vein at birth from singleton babies born after 32 weeks of gestation from138 mothers with gestational diabetes (GDM), 39 mothers with type 2 diabetes (T2DM) and 95 control mothers.

RESULTS

Babies born to mothers with both GDM and T2DM had significantly increased birth weight (Z-score birth weight mean +/- SD: GDM 0.94 +/- 1.31, T2DM 0.53 +/- 1.1) compared to controls (Z-score birth weight -0.08 +/- 1.10). IGFBP-1 was significantly reduced in both diabetic groups (median interquartile range: GDM 67(31-137) ng/ml, T2DM 59(29-105) ng/ml, control 114(56-249) ng/ml). Cord IGF-1 was significantly increased in cord blood of infants of mothers with GDM (42.2 +/- 16.3 ng/ml vs. control 34.7 +/- 18.5 ng/ml) but not T2DM (38.7 +/- 17.4 ng/ml). In all offspring, IGF-1 and IGFBP-1 were positively and negatively correlated with birth weight, respectively.

CONCLUSIONS

Maternal diabetes results in inverse changes of circulating fetal IGF-1 and IGFBP-1 at birth. A decrease in circulating IGFBP-1 and to a lesser extent an increase in circulating IGF-1 may present an important mechanism that contributes to increased birth weight in diabetic pregnancies.

A prospective, randomized, multicenter trial of tacrolimus-based therapy with or without basiliximab in pediatric renal transplantation

In a 6-month, multicenter, randomized, controlled, open-label, parallel-group trial, we investigated the efficacy and safety of adding basiliximab to a standard tacrolimus-based regimen in pediatric renal transplant recipients. Patients < 18 years received tacrolimus/azathioprine/steroids (TAS, n = 93) or tacrolimus/azathioprine/steroids/basiliximab (TAS + B, n = 99). Target tacrolimus levels were 10-20 ng/mL between days 0-21 and 5-15 ng/mL thereafter. Steroid dosing was identical in both groups. Basiliximab was administered at 10 mg (patients < 40 kg) or 20 mg (patients > or = 40 kg) within 4 h of reperfusion; the same dose was repeated on day 4. Biopsy-proven acute rejection rates were 20.4% (TAS) and 19.2% (TAS + B); steroid-resistant acute rejection rates were 3.2% and 3.0%, respectively. Patient survival was 100%; graft survival rates were 95% in both arms. The nature and incidence of adverse events were similar in both arms except toxic nephropathy and abdominal pain, which were significantly higher in the TAS + B arm (14.1% vs. 4.3%; p = 0.03 and 11.1% vs. 2.2%; p = 0.02; respectively). Median serum creatinine concentrations at 6 months were 86 micromol/L in the TAS and 91 micromol/L in the TAS + B arm; glomerular filtration rate was 79.4 and 77.6 (mL/min/1.73 m2), respectively. Adding basiliximab to a tacrolimus-based regimen is safe in pediatric patients, but does not improve clinical efficacy.

Insulin-like growth factor binding proteins initiate cell death and extracellular matrix remodeling in the mammary gland

We have demonstrated that insulin-like growth factor binding protein-5 (IGFBP-5) production by mammary epithelial cells increases dramatically during forced involution of the mammary gland in rats, mice and pigs. We proposed that growth hormone (GH) increases the survival factor IGF-I, whilst prolactin (PRL) enhances the effects of GH by decreasing the concentration of IGFBP-5, which would otherwise inhibit the actions of IGFs. To demonstrate a causal relationship between IGFBP-5 and cell death, we created transgenic mice expressing IGFBP-5, specifically, in the mammary gland. DNA content in the mammary glands of transgenic mice was decreased as early as day 10 of pregnancy. Mammary cell number and milk synthesis were both decreased by approximately 50% during the first 10 days of lactation. The concentrations of the pro-apoptotic molecule caspase-3 was increased in transgenic animals whilst the concentrations of two pro-survival molecules Bcl-2 and Bcl-x were both decreased. In order to examine whether IGFBP-5 acts by inhibiting the survival effect of IGF-I, we examined IGF receptor- and Akt-phoshorylation and showed that both were inhibited. These studies also indicated that the effects of IGFBP-5 could be mediated in part by IGF-independent effects involving potential interactions with components of the extracellular matrix involved in tissue remodeling, such as components of the plasminogen system, and the matrix metallo-proteinases (MMPs). Mammary development was normalised in transgenic mice by R3-IGF-I, an analogue of IGF-I which binds weakly to IGFBPs, although milk production was only partially restored. In contrast, treatment with prolactin was able to inhibit early involutionary processes in normal mice but was unable to prevent this in mice over-expressing IGFBP-5, although it was able to inhibit activation of MMPs. Thus, IGFBP-5 can simultaneously inhibit IGF action and activate the plasminogen system thereby coordinating cell death and tissue remodeling processes. The ability to separate these properties, using mutant IGFBPs, is currently under investigation.

Carotenaemia in children is common and benign: most can stay at home

We identified children with elevated plasma carotene levels who attended the Royal Hospital for Sick Children, Glasgow, between July 1998 and April 2001 and carried out a retrospective case record review. Thirty-one children were identified (7 boys; 14 girls) with a median age at presentation of 13 months (range 7m- 11yrs). Twenty-seven (87%) children had simple diet-related carotenaemia and were well. In four cases the hypercarotenaemia reflected nutritional problems with associated failure to thrive. In only one case did the family doctor recognise the condition before referral. Many who attended hospital had laboratory confirmation of the benign diagnosis despite a clear dietary origin. Some had repeat laboratory tests to confirm resolution. Diet-related carotenaemia appears common in our community. The condition appears poorly recognised within primary care and hospital investigations may be over-enthusiastic.

A quantitative RT-PCR study of the mRNA expression profile of the IGF axis during mammary gland development

We have used quantitative RT-PCR to analyse the mRNA expression profile of the major components of the IGF axis in different stages of murine mammary gland development, including late pregnancy, lactation and involution. We have shown that all the genes studied, IGF-I, IGF-II, IGF receptor (IGFR) and IGF-binding protein (IGFBP)-1 to -6, were expressed in every stage, albeit at greatly differing levels and displaying unique expression profiles between developmental stages. IGF-I was always expressed at significantly higher levels than either IGF-II or IGFR. This suggests that IGF-I may be the more important IGF during mammary morphogenesis. Overall, IGFBP-3 demonstrated the highest level of expression of any of the IGFBP genes throughout all the developmental stages studied. However, within developmental stages, by far the highest level of expression of any of the IGFBPs was that of IGFBP-5 at day 2 of involution; this was almost an order of magnitude higher than any of the other IGFBP levels recorded. This corroborated our previous findings that the levels of IGFBP-5 protein are highly elevated in the involuting mammary gland, and demonstrated that this up-regulation of IGFBP-5 operates at the level of transcriptional control or message stability. Comparison of the expression profile for these different genes would strongly suggest that they are likely to have differential functions throughout mammary gland development, and also highlights potential interactions and co-regulation between different members of this axis. In addition, our results have identified some similarities and differences in the expression of IGFBPs between the mouse mammary epithelial cell line, HC11, and the normal mammary gland which are worthy of study, most notably the differential regulation of IGFBP-2 and the site of expression of IGFBP-4 and -6. Overall, this study has demonstrated the importance and complexity of the IGF axis during mammary gland development and provides a valuable resource for future research in this area.

Modulation of the actions of IGFs by IGFBP-5 in the mammary gland

IGFBP-5 has been associated with cell death in a number of systems; recently, the first evidence that it is involved in apoptosis of the mammary gland has been provided by studies, both in vivo and in vitro, involving the addition of exogenous IGFBP-5 and from a transgenic mouse expressing IGFBP-5 on a mammary-specific promoter. These studies have indicated that the effects are mediated in part by inhibition of IGF-signalling and involving members of the Bcl-2 family, but a role for IGF-independent effects cannot be ruled out. These IGF-independent effects involve potential interactions with components of the extracellular matrix involved in tissue remodelling such as components of the plasminogen system. In addition, intracellular events involving nuclear localisation of IGFBP-5 have been shown to have potential to inhibit cell proliferation. IGFBP-5 binds to a considerable number of molecules in the extracellular matrix, but the specific roles of these interactions in modulating its biological effects are poorly understood. The development of IGFBP-5 mutants, with differential binding characteristics, will aid in elucidating the precise roles of IGFBP-5 and potentially offer new therapeutic approaches based on IGF-independent effects in addition to its classical role of modulating IGF actions.

Hormonal control of IGF-binding protein (IGFBP)-5 and IGFBP-2 secretion during differentiation of the HC11 mouse mammary epithelial cell line

The mouse mammary epithelial cell line HC11 upregulates the synthesis of beta-casein (a differentiation marker) following treatment with the lactogenic hormone mix dexamethasone, insulin and prolactin (DIP). We demonstrate that the basal levels of IGF-binding protein (IGFBP)-5 secreted by undifferentiated HC11 cells are upregulated 10-fold during DIP-induced cellular differentiation whereas the level of the other IGFBP species secreted by HC11 cells (IGFBP-2) is downregulated during this process. As previously reported, the combination of all three of these hormones is required for synthesis of the differentiation marker beta-casein, whereas basal IGFBP-5 secretion is evident in the absence of any hormonal treatment and, unlike beta-casein, secretion of this protein can be stimulated by binary combinations of the hormones (although maximal levels of IGFBP-5 are achieved in the presence of all three lactogenic hormones). Additionally, levels of IGFBP-5 can be increased by DIP treatment under conditions (non-competency of HC11 cultures or presence of epidermal growth factor) where DIP treatment does not increase synthesis of beta-casein. For IGFBP-2, dexamethasone is a potent inhibitor of secretion whilst prolactin stimulated the secretion of this binding protein into the medium. For the IGFBP axis in HC11 cells we conclude that, although the levels of IGFBP-5 and -2 are influenced by the state of cellular differentiation, the hormonal regulation of the levels of these IGFBP species can be dissociated from the regulation of beta-casein synthesis. In a further series of experiments we demonstrate that IGF-I is able to replace insulin in the DIP lactogenic hormone mix and by the use of a specific IGF-I receptor blocking antibody indicate that the action of IGF-I is mediated through the cell surface IGF-I receptor and not by cross-reaction of IGF-I ligand at the insulin receptor. We discuss our data in the context of the potential role of the IGF axis in the process of cell differentiation and illustrate the significance of our findings in the context of the physiology and life cycle of the mammary epithelial cell.

Nephrocalcinosis in preterm babies

OBJECTIVES

To determine prospectively the incidence and cause of nephrocalcinosis in preterm infants.

STUDY DESIGN

Inborn babies of gestation less than 32 weeks or birth weight less than 1500 g were eligible to be entered into a prospective observational study. Two renal ultrasound scans were performed, the first at 1 month postnatal age and the second at term or discharge. Data were collected on gestation, birth weight, sex, race, family history of renal calculi, oliguria on first day, respiratory support (ventilation, steroid, and oxygen dependency), and use of nephrotoxic drugs (gentamicin, vancomycin, and frusemide). Intake of fluid, calcium, and phosphate and plasma urea, creatinine, calcium, and phosphate were recorded for the first 6 weeks of life. Random urinary calcium/creatinine, oxalate/creatinine, and urate/creatinine ratios and tubular absorption of phosphate were measured once at term.

RESULTS

A total of 101 preterm infants were studied. Twenty three (23%) had abnormal ultrasound scans. Sixteen (16%) had nephrocalcinosis. On univariate analysis, gestational age, male sex, duration of ventilation, oxygen dependency, duration and frequency of gentamicin treatment, toxic gentamicin/vancomycin levels, and postnatal dexamethasone were significantly associated with nephrocalcinosis. In addition, babies with nephrocalcinosis had a lower intake of fluid, calcium, and phosphate, longer duration of total parenteral nutrition, and higher urinary oxalate/creatinine and urate/creatinine ratios than infants who did not have the condition. There was also a significant association with plasma urea and creatinine but not with plasma calcium or phosphate or urinary calcium. Multivariate analysis showed that the strongest predictors of nephrocalcinosis were duration of ventilation, toxic gentamicin/vancomycin levels, low fluid intake, and male sex.

CONCLUSION

16% of babies born at less than 32 weeks gestation developed nephrocalcinosis. The multifactorial origin, in particular, the association with extreme prematurity and severity of respiratory disease, is confirmed. In addition, an association with male sex, frequency and duration of gentamicin use, and high urinary oxalate and urate excretion is shown.

The carboxy-terminal domain of IGF-binding protein-5 inhibits heparin binding to a site in the central domain

The IGF-binding protein (IGFBP)-5 protein contains consensus heparin binding motifs in both its carboxy (C)-terminal and central domains, although only the C-terminal site has previously been shown to be functional. We have made two chimeric IGFBP proteins by switching domains between rat IGFBP-5 and -2, named BP552 and BP522 to reflect the domains present, and a truncated rat IGFBP-5 mutant (1-168), named BP550. The ability of these proteins and wild-type (wt) IGFBPs-5 and -2 to bind to either IGFs or heparin was determined using biosensor real-time analysis and heparin ligand blotting respectively. We report that the chimeric molecules have IGF binding affinities comparable to those of the native IGFBPs from which they were derived and, as expected, the binding of BP550 to IGFs was greatly compromised. More surprising was the finding that the ability of BP552 and BP550 to bind to heparin was equivalent to that of wtIGFBP-5, whereas wtIGFBP-2 and BP522 failed to bind. These results demonstrate that the active heparin binding site in BP552 and BP550 is contained within the central domain of IGFBP-5, and that this site is active only in the absence of the C-terminal domain. We subsequently mutated two basic amino acids (R136A:R137A) in the central consensus binding sites between residues 132-140. This resulted in the loss of heparin binding for BP550, confirming the importance of these two basic amino acids in the central domain heparin binding activity. In light of these findings, we suggest that C-terminally truncated fragments of IGFBP-5 generated in vivo by proteolysis could retain heparin/extracellular matrix binding properties.

Evaluation of an acute point-of-care system screening for respiratory syncytial virus infection

There continues to be a significant risk of children contracting hospital-acquired infections caused by respiratory syncytial virus (RSV). In order to provide 24 h screening, we examined a point-of-care system (near-patient testing) for use by non-laboratory healthcare workers (HCWs) in a short stay unit adjoining the accident and emergency department of a large paediatric hospital. Three studies were conducted over consecutive winter epidemics, in which 2193 nasopharyngeal aspirates were obtained from children < 2 years old. An average of 23 trained HCWs tested aspirates with the Abbott TESTPACK(R) RSV assay. Material was sent to the virology laboratory for examination for RSV and other respiratory viruses by direct immunofluorescence. The mean performance characteristics of near patient testing were sensitivity 90%, specificity 92%, positive predictive value 92% and negative predictive value 92%. This was acceptable for clinical purposes. The near-patient testing provided a rapid answer and ensured that infants could be segregated according to infection status. Early antiviral treatment could be commenced and needless antibiotics avoided. During the study the hospital-acquired infection rate was the lowest recorded, although this may have been influenced by national trends and lower rates of inpatient care for infants with bronchiolitis.

Differential inhibition of recombinant bovine GH (rbGH) activity in vitro by in vivo enhancing monoclonal antibodies

We have previously described the effects of complexing recombinant bovine growth hormone (rbGH) with the in vivo enhancing monoclonal antibodies (Mabs) OA11 and OA15 and the non-enhancing Mab OA14 on the subsequent activity of GH in different tissue culture models. We reported that all of these Mabs caused the inhibition of GH-stimulated Jak-2 tyrosine kinase phosphorylation in the GH responsive pre-adipocyte cell line 3T3-F442A. However, using the mouse myeloid cell line FDC-P1 transfected with the full length ovine GH receptor (GHR), we subsequently found that OA11 and OA14 remained inhibitory with respect to the end point measurement of GH stimulated mitogenesis but that OA15 had no inhibitory effect on GH stimulated mitogenesis in this cell line. In order to correlate longer term mitogenic effects of Mab-GH complexes with signalling events in this transfected cell line model, we now report on the effects of complexing with Mab on the subsequent GH stimulated phosphorylation of Stat5b (signal transducer and activator of transcription). In agreement with our data for the mitogenic activity of GH-Mab complexes, we found that OA11 and OA14 inhibit GH activation of Stat5b but that OA15 is not inhibitory. Further to this, the dose-response effect of both OA11 and OA14 on the GH stimulation of Stat5b in the FDC-P1-oGHR transfected cells correlates with the previously described dose-response effects for both Mabs in the context of GH stimulation of mitogenic effects. We conclude that in this oGHR transfected cell line model, Mab effects on short and long term GH signalling events are tightly correlated. The observation that neither of the in vivo enhancing Mabs--OA11 or OA15--amplifies the response to GH in our transfected cell line model, coupled with the differential nature of Mab effects on GH activity (OA11--inhibition; OA15--no effect) may argue for an in vivo mechanism for enhancement of GH activity.

Uterine carcinosarcomas in patients receiving tamoxifen. A report of 19 cases

Uterine carcinosarcomas are highly aggressive neoplasms with a tendency to early extrauterine spread, high stage at diagnosis, and a poor prognosis. Tamoxifen is widely used as adjuvant therapy in the treatment of breast cancer and is known to cause endometrial proliferative lesions, including adenocarcinoma. In recent years, there have been occasional reports of uterine carcinosarcoma in patients taking tamoxifen. The aim of this study is to describe the clinicopathologic profile in 19 women taking tamoxifen who subsequently developed uterine carcinosarcoma. Nineteen patients were identified from cases of uterine carcinosarcoma diagnosed at three institutions. The case notes were examined and the pathology reviewed. The age at diagnosis of carcinosarcoma ranged from 47 to 91 years (mean 71 years). All patients were postmenopausal and received 20 mg tamoxifen daily; the duration of treatment ranged from 1 to 15 years (mean 7.1 years). The cumulative dose of tamoxifen ranged from 7.3 to 109.5 g. Ten tumors were stage I, one stage II, seven stage III, and one stage IV. Ten of the carcinosarcomas were homologous, and nine contained heterologous elements in the form of rhabdomyoblasts (six cases) or malignant cartilage (three cases). The overall prognosis was extremely poor. Fifteen patients died within 35 months of the diagnosis of carcinosarcoma (mean 12 months). Two patients are alive with very short follow-up periods, and two were lost to follow-up. The reported data support an association between tamoxifen therapy and the development of uterine carcinosarcoma. The risk is likely to be highest in those patients who have been taking tamoxifen for a prolonged period. A majority of tumors in the present study were stage I, and this suggests that uterine carcinosarcomas in patients taking tamoxifen may be diagnosed at an earlier stage than those arising de novo. However, the prognosis was still poor even with low-stage disease. Properly controlled epidemiological studies are necessary to confirm an association between tamoxifen and uterine carcinosarcoma.

Overlap of IGF- and heparin-binding sites in rat IGF-binding protein-5

Using site-directed mutagenesis, we have undertaken a study of a potential IGF-binding site in the C-terminal domain of rat IGFBP-5, lying close to or within a previously described heparin-binding domain (residues 201-218) in this protein. After analysis of binding activity using three different methods - ligand blotting, solution phase equilibrium binding and biosensor measurement of real-time on- and off-rates - we report that the mutation of two highly conserved residues within this region (glycine 203 and glutamine 209) reduces the affinity of the binding protein for both IGF-I and IGF-II, while having no effect on heparin binding. In addition, we confirm that mutation of basic residues within the heparin-binding domain (R201L, K202E, K206Q and R214A) results in a protein that has attenuated heparin binding but shows only a small reduction in affinity for IGF-I and -II. Previous findings have described the reduction in affinity of IGFBP-5 for IGFs that occurs after complexation of the binding protein with heparin or other components of the extracellular matrix (ECM) and have postulated that such an interaction may result in conformational changes in protein structure, affecting subsequent IGF interaction. Our data suggesting potential overlap of heparin- and IGF-binding domains argue for a more direct effect of ECM modulation of the affinity of IGFBP-5 for ligand by partial occlusion of the IGF-binding site after interaction with ECM.