A Genetic Mouse Model Recapitulates Immune Checkpoint Inhibitor-Associated Myocarditis and Supports a Mechanism-Based Therapeutic Intervention

Immune checkpoint inhibitors (ICI) targeting CTLA4 or PD-1/PD-L1 have transformed cancer therapy but are associated with immune-related adverse events, including myocarditis. Here, we report a robust preclinical mouse model of ICI-associated myocarditis in which monoallelic loss of Ctla4 in the context of complete genetic absence of Pdcd1 leads to premature death in approximately half of mice. Premature death results from myocardial infiltration by T cells and macrophages and severe ECG abnormalities, closely recapitulating the clinical and pathologic hallmarks of ICI-associated myocarditis observed in patients. Using this model, we show that Ctla4 and Pdcd1 functionally interact in a gene dosage-dependent manner, providing a mechanism by which myocarditis arises with increased frequency in the setting of combination ICI therapy. We demonstrate that intervention with CTLA4-Ig (abatacept) is sufficient to ameliorate disease progression and additionally provide a case series of patients in which abatacept mitigates the fulminant course of ICI myocarditis. SIGNIFICANCE: We provide a preclinical model of ICI-associated myocarditis which recapitulates this clinical syndrome. Using this model, we demonstrate that CTLA4 and PD-1 (ICI targets) functionally interact for myocarditis development and that intervention with CTLA4-Ig (abatacept) attenuates myocarditis, providing mechanistic rationale and preclinical support for therapeutic clinical studies.See related commentary by Young and Bluestone, p. 537.This article is highlighted in the In This Issue feature, p. 521.

Abstract PR008: Identifying mechanisms of immune evasion in microsatellite instable endometrial cancer mouse models

Introduction: Microsatellite instability (MSI), caused by defects in DNA mismatch repair genes, including MLH1 and MSH2, occur in 30% of endometrial cancers (EC). High mutational loads associated with MSI have been associated with greater immunogenicity, and an increase in immune inhibitory factors such as PD-1 and PD-L1. While immunotherapy with anti-PD-L1 has shown promising results in MSI ECs, up to 40% did not respond, suggesting there are alternate immunosuppressive mechanisms. To improve understanding of response/resistance to immunotherapy, we evaluated immune activation and evasion using a novel immunocompetent mouse model of MSI EC.

Methods: Endometrial lesions were evaluated in mice with MSH2 loss targeted to the endometrium (PRCre+MSH2flox/flox). When aged to 12-16 months, 22% develop hyperplasia and 18% develop spontaneous EC. MSI status was confirmed by PCR. Immune infiltration and function were assessed by immunohistochemistry (IHC) and Nanostring digital spatial profiling. Tumors were evaluated for tumor infiltrating lymphocytes (TIL) based on CD8a expression and found to separate into TILHIGH and TILLOW groups and further characterized to determine immune activation/resistance mechanisms using transcriptome analysis with Affymetrix Clariom D assay and validation by RT-PCR. A gene signature score approach was used to quantify immune-related expression changes for tumors from PRCre+MSH2flox/flox mice and MSI EC patient data from TCGA. Cell lines were generated from tumors and used to evaluate a syngeneic orthotopic mouse model for immunotherapy studies, where immune infiltration was characterized.

Results: All endometrial tumors were MSI and included endometrioid, serous, and mixed histologies. Tumors showed varying degrees of CD8+ T cell infiltration, irrespective of histology. TILHIGH tumors had increased infiltration of dendritic cells and Type I interferon response, including genes IFI203 (fold-change, FC=18.5), IFI204 (FC=11.1) and CXCL9 (FC=5.7). There was no significant difference in type II interferon response. TILLOW tumors had low expression of IFN-associated genes. TILHIGH tumors also exhibited increased immune exhaustion markers such as TIM3 (FC=2.4) and LAG3 (FC=3.2). Tumoral PD-L1 expression was negative (<1% of positive cells). Similar to our mouse model, TILHIGH MSI uterine cancer patients from TCGA also showed activation of type I interferon, increased dendritic cell infiltration, and increased T cell exhaustion markers. Primary cell lines used in an orthotopic mouse model retained the immune profile of the original tumor.

Conclusions: Elucidating immune activation and evasion mechanisms is critical for improving immunotherapies. The PRCre+MSH2flox/flox mouse model reflects the spectrum of immunogenicity observed in patients. A panel of primary cell lines generated from this model are an important tool that enable studies of immunotherapy efficacy and resistance mechanisms, in both immunogenic and non-immunogenic tumors.

Citation Format: Brenda Melendez, Emily Hinchcliff, Nisha Gokul, Xiaoping Su, Daniel McGrail, Elizabeth Whitley, Russell Broaddus, Rosemarie Schmandt, Karen Lu, Melinda Yates. Identifying mechanisms of immune evasion in microsatellite instable endometrial cancer mouse models [abstract]. In: Proceedings of the AACR Virtual Special Conference: Endometrial Cancer: New Biology Driving Research and Treatment; 2020 Nov 9-10. Philadelphia (PA): AACR; Clin Cancer Res 2021;27(3_Suppl):Abstract nr PR008.

Abstract 3421: Identifying mechanisms of immune evasion in microsatellite instable endometrial cancers

Inherited or sporadic defects in mismatch repair genes (MLH1, MSH2, MSH6, and PSM2) can lead to microsatellite instable (MSI) tumors, most commonly colon, endometrial or gastric tumors. High mutation rates in MSI tumors have been associated with greater immunogenicity, but these tumors can evade immune response. Recently developed mouse models of MSI endometrial cancer (EC) were used to evaluate immune surveillance mechanisms.

Uterine-targeted MSH2 knockout (PR-Cre+MSH2flox/flox) mice were characterized and determined that 22% of mice develop spontaneous EC by 12-16 months of age. Microsatellite instability was evaluated by PCR. Immune infiltration was quantified by immunohistochemistry (IHC) using FoxP3 (Tregs), CD11b (myeloid cells) and CD8 (tumor infiltrating lymphocytes, TILs) antibodies. Tumors were divided into TILHigh and TILLow (<5 TIL/mm2). Comprehensive transcriptome analysis of tumor and normal controls was performed using the Affymetrix Clariom D assay. A subset of candidate gene changes were validated by RT-PCR and at the protein level by IHC. Cell lines were generated from spontaneous tumors and used for orthotopic syngeneic tumor studies of advanced EC. Immune infiltration in orthotopic tumors was characterized using flow cytometry.

All endometrial tumors from PR-Cre+MSH2flox/flox mice were MSI and included endometrioid, serous, and mixed histologies. Tumors showed varying degrees of immune infiltrate, irrespective of histology. Of 7 tumors, 4 (57%) were TILHigh and 3 (43%) were TILLow. Transcriptome analysis showed TILHigh tumors upregulated innate immunity related pathways including, pattern recognition-associated factors, Type I IFN signaling molecules and CXCL5. Activation of adaptive immunity was observed by an increase in T cell chemoattractants, CXCL9 and CCL21. TILHigh tumors displayed at least a 2-fold increase in MHC class I molecules and CD86 needed for T cell activation. IL1A, CSF1, and TGFB2 (cytokines involved in immunosuppressive cell recruitment and induction) were also highly expressed. IHC confirmed co-localization of TILs with myeloid cells and Tregs in TILHigh tumors. TILLow tumors had decreased expression of several members in the IFN family responsible for initiating innate responses. Primary cell lines from TILHigh and TILLow tumors used in an orthotopic syngeneic mouse model retained the immune profile of the original tumor.

Understanding mechanisms of immune evasion is critical for improving immunotherapy. This model of MSI EC reflects the spectrum of immunogenicity observed in clinical studies. TILHigh tumors express a wide range of factors involved in innate and adaptive anti-tumor responses, while TILLow tumors lack key mediators needed for immune activation. These new models for MSI EC will be essential to test the efficacy of immunotherapies and study mechanisms of resistance.

Citation Format: Brenda Melendez, Emily Hinchcliff, Nisha Gokul, Elizabeth Whitley, Russell R. Broaddus, Rosemarie E. Schmandt, Karen H. Lu, Melinda S. Yates. Identifying mechanisms of immune evasion in microsatellite instable endometrial cancers [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 3421.

The Relation Between Cognitive Performance and Symptom Factors Following Concussion

Purpose

The purpose of this study was to explore if symptom factors are related to cognitive outcomes. Prior studies have examined the relationship of individual symptoms to cognition. However, the relation between empirically-derived symptom factors and cognitive outcomes has yet to be explored.

Methods

Data were extracted via retrospective chart review of 691 patients (aged 10–24, mean: 14.99±2.63). Participants completed ImPACT and the PCSS within 14 days of injury (mean: 9.27±3.37). Predictors were PCSS factor scores of Cognitive-Fatigue-Migraine (CFM), Affective (AFF), Somatic (SOM), and Sleep (SLP) (Kontos et al., 2012). Outcomes examined were ImPACT composite scores. Univariate analyses were performed and values with p < 0.10 were entered into stepwise linear regression (LR) models. Retained predictors in each LR model had p values <.05.

Results

Verbal memory was predicted by CFM, SOM, age, and gender. Visual memory was predicted by CFM and SOM. Visual motor speed was predicted by age, gender, CFM, SOM, and AFF. Reaction time was best predicted by SOM, CFM, and age. The variance explained was fairly small (0.08 to 0.21). SLP was not a significant predictor in any LR.

Conclusion

CFM and SOM factors were most predictive of lower cognitive performance, similar to prior studies linking dizziness to longer recovery and post-traumatic migraine to worse cognitive performance. These findings underscore the clinical importance of diverse symptom assessment and injury education. Higher CFM and SOM scores may also serve as proxy for injury severity, which we would expect to be associated with worse cognitive performance.

Acute hydrogen sulfide-induced neuropathology and neurological sequelae: challenges for translational neuroprotective research

Hydrogen sulfide (H₂S), the gas with the odor of rotten eggs, was formally discovered in 1777, over 239 years ago. For many years, it was considered an environmental pollutant and a health concern only in occupational settings. Recently, however, it was discovered that H₂S is produced endogenously and plays critical physiological roles as a gasotransmitter. Although at low physiological concentrations it is physiologically beneficial, exposure to high concentrations of H₂S is known to cause brain damage, leading to neurodegeneration and long‐term neurological sequelae or death. Neurological sequelae include motor, behavioral, and cognitive deficits, which are incapacitating. Currently, there are concerns about accidental or malicious acute mass civilian exposure to H₂S. There is a major unmet need for an ideal neuroprotective treatment, for use in the field, in the event of mass civilian exposure to high H₂S concentrations. This review focuses on the neuropathology of high acute H₂S exposure, knowledge gaps, and the challenges associated with development of effective neuroprotective therapy to counteract H₂S‐induced neurodegeneration.

The Public Health Framework of Legalized Marijuana in Colorado

On January 1, 2014, Colorado became the first state in the nation to sell legal recreational marijuana for adult use. As a result, Colorado has had to carefully examine potential population health and safety impacts as well as the role of public health in response to legalization. We have discussed an emerging public health framework for legalized recreational marijuana. We have outlined this framework according to the core public health functions of assessment, policy development, and assurance. In addition, we have discussed challenges to implementing this framework that other states considering legalization may face.

A patient navigation intervention for drug-involved former prison inmates

BACKGROUND

Former prison inmates experience high rates of hospitalizations and death during the transition from prison to the community, particularly from drug-related causes and early after release. The authors designed a randomized controlled trial (RCT) of patient navigation to reduce barriers to health care and hospitalizations for former prison inmates.

METHODS

Forty former prison inmates with a history of drug involvement were recruited and randomized within 15 days after prison release. Participants were randomized to receive 3 months of patient navigation (PN) with facilitated enrollment into an indigent care discount program (intervention) or facilitated enrollment into an indigent care discount program alone (control). Structured interviews were conducted at baseline, 3 months, and 6 months. Outcomes were measured as a change in self-reported barriers to care and as the rate of health service use per 100 person-days.

RESULTS

The mean number of reported barriers to care was reduced at 3 and 6 months in both groups. At 6 months, the rate of emergency department/urgent care visits per 100 person-days since baseline was 1.1 among intervention participants and 0.5 among control participants (P = .04), whereas the rate of hospitalizations per 100 person-days was 0.2 in intervention participants and 0.6 in control participants (P = .04).

CONCLUSIONS

Recruitment of former inmates into an RCT of patient navigation was highly feasible, but follow-up was limited by rearrests. Results suggest a significantly lower rate of hospitalizations among navigation participants, although the rate of emergency department/urgent care visits was not improved. Patient navigation is a promising, pragmatic intervention that may be effective at reducing high-cost health care utilization in former prison inmates.

Costs and outcomes evaluation of patient navigation after abnormal cancer screening: evidence from the Patient Navigation Research Program

BACKGROUND

Navigators can facilitate timely access to cancer services, but to the authors' knowledge there are little data available regarding their economic impact.

METHODS

The authors conducted a cost-consequence analysis of navigation versus usual care among 10,521 individuals with abnormal breast, cervical, colorectal, or prostate cancer screening results who enrolled in the Patient Navigation Research Program study from January 1, 2006 to March 31, 2010. Navigation costs included diagnostic evaluation, patient and staff time, materials, and overhead. Consequences or outcomes were time to diagnostic resolution and probability of resolution. Differences in costs and outcomes were evaluated using multilevel, mixed-effects regression modeling adjusting for age, race/ethnicity, language, marital status, insurance status, cancer, and site clustering.

RESULTS

The majority of individuals were members of a minority (70.7%) and uninsured or publically insured (72.7%). Diagnostic resolution was higher for navigation versus usual care at 180 days (56.2% vs 53.8%; P = .008) and 270 days (70.0% vs 68.2%; P < .001). Although there were no differences in the average number of days to resolution between the 2 groups (110 days vs 109 days; P = .63), the probability of ever having diagnostic resolution was higher for the navigation group versus the usual-care group (84.5% vs 79.6%; P < .001). The added cost of navigation versus usual care was $275 per patient (95% confidence interval, $260-$290; P < .001). There was no significant difference in stage distribution among the 12.4% of patients in the navigation group vs 11% of the usual-care patients diagnosed with cancer.

CONCLUSIONS

Navigation adds costs and modestly increases the probability of diagnostic resolution among patients with abnormal screening test results. Navigation is only likely to be cost-effective if improved resolution translates into an earlier cancer stage at the time of diagnosis.

Patient navigation for breast and colorectal cancer treatment: a randomized trial

BACKGROUND

There is limited high-quality evidence about the impact of patient navigation (PN) on outcomes for patients with diagnosed cancer.

METHODS

We pooled data from two sites from the national Patient Navigation Research Program. Patients (n = 438) with newly diagnosed breast (n = 353) or colorectal cancer (n = 85) were randomized to PN or usual care. Trained lay navigators met with patients randomized to PN to help them assess treatment barriers and identify resources to overcome barriers. We used intent-to-treat analysis to assess time to completion of primary treatment, psychologic distress (impact of events scale), and satisfaction (patient satisfaction with cancer-related care) within 3 months after initiation of cancer treatment.

RESULTS

The sample was predominantly middle-aged (mean age = 57) and female (90%); 44% were race-ethnic minorities (44%), 46% reported lower education levels, 18% were uninsured, and 9% reported a non-English primary language. The randomized groups were comparable in baseline characteristics. Primary analysis showed no statistically significant group differences in time to completion of primary cancer treatment, satisfaction with cancer-related care, or psychologic distress. Subgroup analysis showed that socially disadvantaged patients (i.e., uninsured, low English proficiency, and non-English primary language) who received PN reported higher satisfaction than those receiving usual care (all P < 0.05). Navigated patients living alone reported greater distress than those receiving usual care.

CONCLUSIONS

Although the primary analysis showed no overall benefit, the subgroup analysis suggests that PN may improve satisfaction with care for certain disadvantaged individuals.

IMPACT

PN for cancer patients may not necessarily reduce treatment time nor distress.

The impact of patient navigation on receipt of quality breast cancer treatment in the national patient navigation research program

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Background: The discrepancy in breast cancer outcomes for underserved populations has been linked to lack of receipt of quality treatment. Patient navigation programs are being rapidly adopted as a model to improve cancer outcomes for these vulnerable populations, yet the effect of navigation on their quality of cancer care is unknown. Methods: We conducted a secondary analysis of the National Patient Navigation Research Program (PNRP) data to assess the impact of navigation on receipt of quality care among women diagnosed with breast cancer. Data pooled from 7 PRNP sites were used to determine the proportion of newly diagnosed cancer patients whose care met National Comprehensive Cancer Network (NCCN) quality metrics: 1) hormonal therapy for HR+ patients 2) post-lumpectomy radiation therapy; and 3) chemotherapy for hormone negative, >1cm tumors, in patients <70 years of age. Chi-square tests were performed to compare probability of receiving recommended care among navigated and control patients. Results: A total of 1,006 breast cancer patients eligible for treatment were enrolled across all sites: 491 (49%) in the intervention arm, 515 (51%) in the control arm (mean age: 56 years; 38% African American, 23% Hispanic; 13% uninsured and 38% Medicaid). Among those eligible for hormone therapy, 283/357 (79%) navigated patients received hormonal therapy compared to 237/371 (64%) of controls (p < 0.001). Among those eligible for radiation therapy post lumpectomy, 235/277 (85%) of navigated patients received radiation compared to 270/324 (83%) of controls (p=0.62). Among those eligible for chemotherapy, 79/122 (65%) of navigated patients received chemotherapy compared to 81/100 (81%) of controls (p < 0.007). Logistic regression models to determine the odds of receiving recommended care for navigated and non-navigated patients, adjusting for patient demographics, will be conducted. Conclusions: Navigation had a positive effect for receipt of hormonal therapy, but not for radiation therapy and chemotherapy. Future studies are needed to assess the role navigation may play in ensuring quality care for the most vulnerable.

Influence of maternal and paternal IQ on offspring health and health behaviours: evidence for some trans-generational associations using the 1958 British birth cohort study

PURPOSE

Individuals scoring poorly on tests of intelligence (IQ) have been reported as having increased risk of morbidity, premature mortality, and risk factors such as obesity, high blood pressure, poor diet, alcohol and cigarette consumption. Very little is known about the impact of parental IQ on the health and health behaviours of their offspring.

METHODS

We explored associations of maternal and paternal IQ scores with offspring television viewing, injuries, hospitalisations, long standing illness, height and BMI at ages 4 to 18 using data from the National Child Development Study (1958 birth cohort).

RESULTS

Data were available for 1446 mother-offspring and 822 father-offspring pairs. After adjusting for potential confounding/mediating factors, the children of higher IQ parents were less likely to watch TV (odds ratio (95% confidence interval) for watching 3+ vs. less than 3hours per week associated with a standard deviation increase in maternal or paternal IQ: 0.75 (0.64, 0.88) or 0.78 (0.64, 0.95) respectively) and less likely to have one or more injuries requiring hospitalisation (0.77 (0.66, 0.90) or 0.72 (0.56, 0.91) respectively for maternal or paternal IQ).

CONCLUSIONS

Children whose parents have low IQ scores may have poorer selected health and health behaviours. Health education might usefully be targeted at these families.

Early lesion formation in colorectal carcinogenesis is associated with adiponectin status whereas neoplastic lesions are associated with diet and sex in C57BL/6J mice

Adiponectin is an antiinflammatory and insulin-sensitizing hormone that is decreased in obesity. Although controversial, it has been suggested that decreased adiponectin contributes to colorectal cancer risk in obesity. To further investigate the role of adiponectin in obesity-linked colorectal carcinogenesis, we used male and female adiponectin knockout (KO) and wild-type (Wt) C57BL/6J mice. Tumorigenesis was induced in all mice with the combined treatment of azoxymethane (AOM) and dextran sodium sulfate (DSS). Following AOM/DSS treatment, mice were fed a low-fat control (LFC), or high-fat lard (HFL) diet for 7 1/2 wk. KO mice developed fewer total lesions than Wt mice, males developed fewer lesions than females, and mice fed the HFL diet developed fewer lesions than those fed the LFC diet. Early lesion multiplicity was influenced by genotype, whereas advanced lesion development was influenced by sex and diet. Moreover, lesion types were differentially correlated with serum adipokines and colon gene expression of adiponectin receptors, insulin receptor, and toll-like receptor 4. These data suggest that in the AOM/DSS model of carcinogenesis, adiponectin functions to promote early lesion development whereas sex and diet are important regulators of advanced lesion development through pathways involved in inflammation and insulin signaling.

Establishing common cost measures to evaluate the economic value of patient navigation programs

BACKGROUND

Patient navigation is an intervention aimed at reducing barriers to health care for underserved populations as a means to reduce cancer health disparities. Despite the proliferation of patient navigation programs across the United States, information related to the economic impact and sustainability of these programs is lacking.

METHODS

After a review of the relevant literature, the Health Services Research (HSR)-Cost workgroup of the American Cancer Society National Patient Navigator Leadership Summit met to examine cost data relevant to assessing the economic impact of patient navigation and to propose common cost metrics.

RESULTS

Recognizing that resources available for data collection, management, and analysis vary, 5 categories of core and optional cost measures were identified related to patient navigator programs, including program costs, human capital costs, direct medical costs, direct non-medical costs, and indirect costs.

CONCLUSIONS

Information demonstrating economic as well as clinical value is necessary to make decisions about sustainability of patient navigation programs. Adoption of these common cost metrics are recommended to promote understanding of the economic impact of patient navigation and comparability across diverse patient navigation programs.

Stems to GEMs: impact of stem cell technology on engineered animal models

Collectively, these presentations introduced the audience to the roles of ES cells in generating phenotypes of transgenic animals,and they provided examples where the GEMs were used to define molecular mechanisms of disease or where ES cells were used as a therapeutic modality. Points of discussion among audience members reinforced the importance of strain-associated background lesions in animal models, technological advances in imaging functional biology, opportunities for stem cell therapies, and ubiquitination in regulation of cell proliferation. The 2012 American College of Veterinary Pathologists symposium ‘‘Evolutionary Aspects of Animal Models’’ will focus on the proper selection of a relevant animal model in biomedical research as critical to investigative success. Recent work characterizing rapid evolutionary changes and differences in physiology between species questions the validity of some comparative models. Dr. Robert Hamlin will be speaking on cardiovascular disease in ‘‘Animals as Models of Human Cardiovascular Disease: Or the Search to Overcome Outdated Evolutionary Homeostatic Mechanisms.’’ Dr. Stefan Niewiesk will discuss evolutionary factors that affect modeling the human immune system in ‘‘Of Mice and Men: Evolutionarily, What Are the Best Rodent Models of the Human Immune System for Infectious Disease Research?’’ Dr. Steven Austad will consider evolution in ‘‘Evolutionary Aspects of Animal Models of Aging.’’Finally, Dr. Elizabeth Uhl will conclude the session with ‘‘Modeling Disease Phenotypes: How an Evolutionary Perspective Enhances the Questions.’’

Associations between types of dietary fat and fish intake and risk of stroke in the Caerphilly Prospective Study (CaPS)

BACKGROUND

Few population-based longitudinal studies on diet and stroke have been conducted, and associations between dietary fat and fish intake and risk of stroke are unclear.

OBJECTIVES

To prospectively examine relationships between intakes of total fat, saturated fat, unsaturated fat, white fish and oily fish and risk of stroke in a well-defined population of 2710 middle-aged men.

STUDY DESIGN

Prospective cohort study.

METHODS

Detailed information on health and lifestyle factors was collected via interview, and diet was assessed on three occasions using a food frequency questionnaire. Stroke ascertainment was by self-report and inspection of clinical records. Extracted data were assessed by two independent experts.

RESULTS

During a median follow-up of 18 years, 225 strokes (209 ischaemic and 19 haemorrhagic) were eligible for inclusion in the analyses. For most recent diet (i.e. food frequency questionnaire data collected immediately prior to the stroke event), there was a slightly lower risk of stroke with higher intakes of unsaturated fat and oily fish. Multiple adjusted hazard ratios (HRs) for the lowest vs highest quintiles of unsaturated fat and oily fish intakes were 0.66 [95% confidence interval (CI) 0.41-1.05, P trend = 0.13] and 0.66 (95% CI 0.41-1.05, P trend = 0.09), respectively. Baseline and cumulative diets showed a slightly higher risk of stroke with higher intake of white fish; HRs for the lowest vs highest quintiles were 1.16 (95% CI 0.76-1.77, P trend = 0.22) and 1.28 (95% CI 0.77-2.13, P trend = 0.48), respectively.

CONCLUSIONS

Overall, strong associations were not found between intakes of different types of fat and fish and risk of stroke in middle-aged men. The inverse associations between unsaturated fat and oily fish intakes and risk of stroke were weak, but the direction of association was broadly consistent with other studies; however, these relatively weak associations were not conventionally statistically significant.

The association of childhood height, leg length and other measures of skeletal growth with adult cardiovascular disease: the Boyd-Orr cohort

BACKGROUND

Taller adults have a reduced risk of cardiovascular disease, and there is some evidence that pre-adolescent exposures, indexed by leg length, underlie this association. Associations with other aspects of skeletal size in childhood have not previously been investigated.

METHODS

We have examined associations of cardiovascular mortality and morbidity with childhood height, shoulder breadth, leg, trunk and foot length using a cohort of children whose families participated in a 1937-9 survey of diet and health followed up for 59 years.

RESULTS

Altogether 2642 traced participants had at least one anthropometric measurement; a subsample (n=1043), completed the Rose angina questionnaire and provided information about doctor-diagnosed ischaemic heart disease (IHD) in 1997-8. Childhood stature was weakly inversely associated with cardiovascular mortality, and leg length was the component with the strongest associations. There was evidence from secondary analyses that childhood anthropometric measurements were inversely related to early (age <65 years) rather than late cardiovascular mortality. Childhood stature was inversely associated with self-reported IHD and associations with leg length were strongest. Associations were somewhat attenuated in models including terms for having been breastfed and socioeconomic position.

CONCLUSION

Pre-adult exposures are more strongly associated with cardiovascular morbidity than mortality, and they affect premature cardiovascular mortality more than later mortality.

Evaluating the cost-effectiveness of cancer patient navigation programs: conceptual and practical issues

Patient navigators-individuals who assist patients through the healthcare system to improve access to and understanding of their health and healthcare-are increasingly used for underserved individuals at risk for or with cancer. Navigation programs can improve access, but it is unclear whether they improve the efficiency and efficacy of cancer diagnostic and therapeutic services at a reasonable cost, such that they would be considered cost-effective. In the current study, the authors outline a conceptual model for evaluating the cost-effectiveness of cancer navigation programs. They describe how this model is being applied to the Patient Navigation Research Program, a multicenter study supported by the National Cancer Institute's Center to Reduce Cancer Health Disparities. The Patient Navigation Research Program is testing navigation interventions that aim to reduce time to delivery of quality cancer care (noncancer resolution or cancer diagnosis and treatment) after identification of a screening abnormality. Examples of challenges to evaluating cost-effectiveness of navigation programs include the heterogeneity of navigation programs, the sometimes distant relation between navigation programs and outcome of interest (eg, improving access to prompt diagnostic resolution and life-years gained), and accounting for factors in underserved populations that may influence both access to services and outcomes. In this article, the authors discuss several strategies for addressing these barriers. Evaluating the costs and impact of navigation will require some novel methods, but will be critical in recommendations concerning dissemination of navigation programs.

Ex vivo viability of canine and feline sarcomas: a pilot study

Assay-based chemotherapeutic protocols are common in human gynecologic oncology, most notably for patients with ovarian or breast cancer. The current study examines ex vivo incubation conditions necessary for the assessment of sarcomatous tumor response to potential chemotherapeutic drugs. Slices of sarcomatous tumors were incubated in one of two culture media. Viability indices were measured and compared across time and between media. Neither medium was sufficient to support the growth of sarcomatous tumor tissue slices based on the indices studied. It is likely that sarcomatous tumors require a different approach for ex vivo assessment than their epithelial counterparts. Our long-term goal is to incubate tumor slices with chemotherapeutic agents to predict the in vivo tumor response based on the maintenance or loss of slice viability within this system.

Intelligence in early adulthood and subsequent risk of unintentional injury over two decades: cohort study of 1 109 475 Swedish men

BACKGROUND

There is growing evidence of an inverse association between intelligence (IQ) and unintentional injuries.

METHODS

Analyses are based on a cohort of 1 109 475 Swedish men with IQ measured in early adulthood. Men were followed up for an average 24 years, and hospital admissions for unintentional injury were recorded.

RESULTS

198 133 (17.9%) men had at least one hospital admission for any unintentional injury during follow-up. The most common cause of unintentional injury was falling, followed by road accidents, poisoning, fire and drowning. In addition, 14 637 (1.3%) men had at least one admission for complications of medical care. After adjusting for confounding variables, lower IQ scores were associated with an elevated risk of any unintentional injury (HR (95% CI) per SD decrease in IQ: 1.15 (1.14 to 1.15)) and of cause-specific injuries other than drowning (poisoning (1.53 (1.49 to 1.57)), fire (1.36 (1.31 to 1.41)), road traffic accidents (1.25 (1.23 to 1.26)), medical complications (1.20 (1.18 to 1.22)) and falling (1.17 (1.16 to 1.18))). These gradients were stepwise across the full IQ range.

CONCLUSIONS

Low IQ scores in early adulthood were associated with a subsequently increased risk of unintentional injury. A greater understanding of mechanisms underlying these associations may provide opportunities and strategies for prevention.

Salivary gland thrombostasin isoforms differentially regulate blood uptake of horn flies fed on New Zealand White rabbits

Thrombostasin (TS) is a previously characterized anticlotting protein with multiple isoforms found in the saliva of horn flies. In this report, the effect of TS isoforms on blood feeding was assessed using individual flies that carried corresponding ts allelles. Laboratory studies of horn fly blood feeding were conducted using colony-reared flies fed on New Zealand White (NZW) rabbits. After timed 20-min feeding periods, each fly was characterized for gender, blood volume uptake, and ts genotype. The results showed that mean blood volumes obtained by individual flies were not related to fly gender but were correlated to the ts genotype(s) carried by each fly. A fly having one or both ts alleles coding for the TS9 isoform took less blood than those possessing one or both ts alleles coding for the TS10 isoform. These results confirm the significant role that TS plays in horn fly feeding and highlight the differential impact of TS protein isoforms that vary by as few as three amino acids.

Collarless polished tapered stem: clinical and radiological results at a minimum of ten years' follow-up

We retrospectively reviewed 175 patients (191 hips) who had undergone primary cemented total hip replacement between November 1992 and November 1995 using a collarless polished double-tapered femoral component after a minimum of ten years (mean 11.08; 10 to 12.8). All stems were implanted using contemporary cementing techniques with a distal cement restrictor, pressurised lavage, retrograde cementing with a gun and proximal pressurisation. Clinical outcome was assessed using the Harris Hip score. Radiological analysis was performed on calibrated plain radiographs taken in two planes. Complete radiological data on 110 patients (120 hips) and clinical follow-up on all the surviving 111 patients (122 hips) was available. The fate of all the hips was known. At final follow-up, the mean Harris Hip score was 86 (47 to 100), and 87 of 116 patients (75%) had good or excellent scores. Survival with revision of the stem for aseptic loosening as the endpoint was 100%; and survival with revision of the stem for any reason was 95.9% (95% confidence interval 87.8 to 96.8) at ten years. All the stems subsided vertically at the stem-cement interface in a predictable pattern, at an overall mean rate of 0.18 mm per year (0.02 to 2.16), but with a mean rate of 0.80 mm (0.02 to 2.5) during the first year. The mean total subsidence was 1.95 mm (0.21 to 24). Only three stems loosened at the cement-bone interface. There was excellent preservation of proximal femoral bone stock. There was a high incidence of Brooker III and IV heterotopic ossification affecting 25 patients (22%). The collarless polished tapered stem has an excellent clinical and radiological outcome at a minimum of ten years' follow-up. The pattern and magnitude of subsidence of the stem within the cement mantle occurred in a predictable pattern, consistent with the design philosophy.

Ten-year life expectancy after primary total hip replacement

We determined the ten-year life expectancy of 5831 patients who had undergone 6653 elective primary total hip replacements at a regional orthopaedic centre between April 1993 and October 2004. Using hospital, general practitioner and the local health authority records, we recorded the dates of death for those who died following surgery. The mean age at operation was 67 years (13 to 96) with a male:female ratio of 2:3. Of 1154 patients with a ten-year follow-up 340 (29.5%) had died a mean of 5.6 years (0 to 10) after surgery. Using Kaplan-Meier curves, the ten-year survival was 89% in patients under 65 years at surgery, 75% in patients aged between 65 and 74 years, and 51% in patients over 75. The standardised mortality rates were considerably higher for patients under 45 years, 20% higher for those between 45 and 64 years, and steadily reduced in patients aged 65 and over. The survival of cemented hip replacement derived from the Swedish Hip Arthroplasty Register Annual Report 2004 exceeds the life expectancy of patients over the age of 60 in our area, suggesting that cemented hip replacement is the procedure of choice in this population.

Determinants of outcome in critically ill octogenarians after surgery: an observational study

BACKGROUND

The population in the UK is growing older and the number of elderly patients cared for on intensive care units (ICU) is increasing. This study was designed to identify risk factors for mortality in critically ill patients of >80 yr of age after surgery.

METHODS

We identified 275 patients, aged 80 yr or greater, admitted to the ICU after surgery. After exclusions, 255 were selected for further analysis. Multivariate analysis was then performed to determine the covariates associated with hospital mortality.

RESULTS

The overall ICU and hospital mortality was 20.4% and 33.3%, respectively. Patients who received i.v. vasoactive drugs on days 1 and 2 had hospital mortality of 54.4% and 60.5%, respectively. Multivariate analysis showed that requirement for i.v. vasoactive drugs within the first 24 h on ICU [odds ratio (OR) 4.29; 95% CI, 2.35-7.84, P<0.001] and requirement for i.v. vasoactive drugs for a further 24 h (OR 3.63; 95% CI, 1.58-8.37, P<0.01) were associated with hospital mortality. The requirement for i.v. vasoactive drugs was also strongly associated with hospital mortality in all the subgroups studied (elective surgery, emergency surgery, and emergency laparotomy).

CONCLUSIONS

For patients aged 80 yr and more, admitted to ICU after surgery, the requirement for i.v. vasoactive drugs in the first and second 24 h was the strongest predictor of hospital mortality.

The Exeter Universal stem: a minimum ten-year review from an independent centre

We reviewed 142 consecutive primary total hip replacements implanted into 123 patients between 1988 and 1993 using the Exeter Universal femoral stem. A total of 74 patients (88 hips) had survived for ten years or more and were reviewed at a mean of 12.7 years (10 to 17). There was no loss to follow-up. The rate of revision of the femoral component for aseptic loosening and osteolysis was 1.1% (1 stem), that for revision for any cause was 2.2% (2 stems), and for re-operation for any cause was 21.6% (19 hips). Re-operation was because of failure of the acetabular component in all but two hips. All but one femoral component subsided within the cement mantle to a mean of 1.52 mm (0 to 8.3) at the final follow-up. One further stem had subsided excessively (8 mm) and had lucent lines at the cement-stem and cement-bone interfaces. This was classified as a radiological failure and is awaiting revision. One stem was revised for deep infection and one for excessive peri-articular osteolysis. Defects of the cement mantle (Barrack grade C and D) were found in 28% of stems (25 hips), associated with increased subsidence (p = 0.01), but were not associated with endosteal lysis or failure. Peri-articular osteolysis was significantly related to the degree of polyethylene wear (p < 0.001), which was in turn associated with a younger age (p = 0.01) and male gender (p < 0.001). The use of the Exeter metal-backed acetabular component was a notable failure with 12 of 32 hips (37.5%) revised for loosening. The Harris-Galante components failed with excessive wear, osteolysis and dislocation with 15% revised (5 of 33 hips). Only one of 23 hips with a cemented Elite component (4%) was revised for loosening and osteolysis. Our findings show that the Exeter Universal stem implanted outside the originating centre has excellent medium-term results.

The association of fetal and childhood growth with risk of schizophrenia. Cohort study of 720,000 Swedish men and women

Previous investigations of the association of schizophrenia with patterns of pre- and post-natal growth have been based on small numbers of cases or have not taken account of the effects of prematurity on birthweight. We investigated the association of fetal growth with schizophrenia in a large cohort of Swedish males and females. We linked data from the Swedish Medical Birth Register (1973-1980), Inpatient and Discharge Register (1988-2002), Military Service Conscription Register (1990-1997), and the Population and Housing Censuses (1970 and 1990). Altogether 719,476 males and females were followed up from the age of 16 for a mean of 9.9 years. There were 736 incident cases of schizophrenia. Even in models that did not control for gestational age there was little evidence of an association between birthweight and schizophrenia (hazard ratio per kg increase in birthweight: 0.90 (95% CI 0.78 to 1.03); the hazard ratio in babies weighing <2.5 kg compared to 3.5-4.0 kg was 1.29 (95% CI 0.85 to 1.96). There was an inverse association of birth length with schizophrenia across the range of birth lengths. Short babies were at an increased risk (hazard ratio per 10 cm increase in birth length: 0.53, 95% CI 0.31 to 0.89 (fully adjusted model)). All associations were little changed when analyses were restricted to term (>36 week gestation) babies. In males, low body mass index and short height at age 18 were associated with increased risk. There is some evidence that patterns of risk in relation to fetal growth differ depending on post-natal growth patterns: the increased risk associated with low body mass index was restricted to long babies who became light adults. The exposures underlying these associations and the biological mechanisms mediating them require clarification.

Radon in homes and risk of lung cancer: collaborative analysis of individual data from 13 European case-control studies

OBJECTIVE

To determine the risk of lung cancer associated with exposure at home to the radioactive disintegration products of naturally occurring radon gas.

DESIGN

Collaborative analysis of individual data from 13 case-control studies of residential radon and lung cancer.

SETTING

Nine European countries.

SUBJECTS

7148 cases of lung cancer and 14,208 controls.

MAIN OUTCOME MEASURES

Relative risks of lung cancer and radon gas concentrations in homes inhabited during the previous 5-34 years measured in becquerels (radon disintegrations per second) per cubic metre (Bq/m3) of household air.

RESULTS

The mean measured radon concentration in homes of people in the control group was 97 Bq/m3, with 11% measuring > 200 and 4% measuring > 400 Bq/m3. For cases of lung cancer the mean concentration was 104 Bq/m3. The risk of lung cancer increased by 8.4% (95% confidence interval 3.0% to 15.8%) per 100 Bq/m3 increase in measured radon (P = 0.0007). This corresponds to an increase of 16% (5% to 31%) per 100 Bq/m3 increase in usual radon--that is, after correction for the dilution caused by random uncertainties in measuring radon concentrations. The dose-response relation seemed to be linear with no threshold and remained significant (P = 0.04) in analyses limited to individuals from homes with measured radon < 200 Bq/m3. The proportionate excess risk did not differ significantly with study, age, sex, or smoking. In the absence of other causes of death, the absolute risks of lung cancer by age 75 years at usual radon concentrations of 0, 100, and 400 Bq/m3 would be about 0.4%, 0.5%, and 0.7%, respectively, for lifelong non-smokers, and about 25 times greater (10%, 12%, and 16%) for cigarette smokers.

CONCLUSIONS

Collectively, though not separately, these studies show appreciable hazards from residential radon, particularly for smokers and recent ex-smokers, and indicate that it is responsible for about 2% of all deaths from cancer in Europe.

35 PRODUCTION OF CLONED MINIATURE CALVES USING CYTOPLASTS FROM COWS OF STANDARD SIZE

Numerous genetically similar cattle for use in research or teaching can be produced with chromatin transfer technology (Sullivan et al. 2004 Biol. Reprod. 70, 146–153). Miniature cattle can provide advantageous biotechnological models for teaching and study of human and animal diseases. Miniature cattle are approximately one fourth the size of standard cattle and, therefore, represent a potentially less expensive, safer, and more easily managed animal model. Our limited attempts to reproduce miniature cattle via in vivo and in vitro production of embryos resulted in poor response to superovulation and logistical challenges in recovering embryos or oocytes due to the small size of the animals. Thus, the purpose of this study was to evaluate the potential of embryos derived by chromatin transfer from fibroblasts of a miniature cow and cytoplasts from cows of standard size to produce viable offspring after transfer into recipient cows of standard size. The donor of somatic cells was a heifer that weighed 7.7 kg at birth. Chromatin transfer resulted in 19% (82/428) blastocyst formation. A total of 66 cloned blastocysts (65 excellent/good quality, 1 fair quality) were transferred into 26 synchronized recipients. While ultrasound revealed 13 pregnancies prior to 67 days of gestation, only 4 pregnancies of 5 fetuses were maintained beyond 100 days. Parturition was induced with dexamethasone and prostaglandin on Day 286 of gestation. One singleton (12.3 kg) and a set of twins (10.2 and 11.1 kg) were healthy at birth and normal at 1 week of age. Two fully developed singletons, weighing 21.4 and 13.6 kg, died in utero. The latter fetus exhibited a fixed dorsolateral deviation of the neck that complicated delivery despite a caudal obstetrical presentation. No abnormalities were noted in the size or structure of any placenta. Our results indicate that healthy miniature calves can be gestated by recipient cows of standard size after transfer of embryos derived by chromatin transfer. Unfortunately, the fetal wastage, fetal anomalies, and stillbirths observed with standard sized cattle also may occur.

Associations of height, leg length, and lung function with cardiovascular risk factors in the Midspan Family Study

BACKGROUND

Taller people and those with better lung function are at reduced risk of coronary heart disease (CHD). Biological mechanisms for these associations are not well understood, but both measures may be markers for early life exposures. Some studies have shown that leg length, an indicator of pre-pubertal nutritional status, is the component of height most strongly associated with CHD risk. Other studies show that height-CHD associations are greatly attenuated when lung function is controlled for. This study examines (1) the association of height and the components of height (leg length and trunk length) with CHD risk factors and (2) the relative strength of the association of height and forced expiratory volume in one second (FEV(1)) with risk factors for CHD.

SUBJECTS AND METHODS

Cross sectional analysis of data collected at detailed cardiovascular screening examinations of 1040 men and 1298 women aged 30-59 whose parents were screened in 1972-76. Subjects come from 1477 families and are members of the Midspan Family Study.

SETTING

The towns of Renfrew and Paisley in the West of Scotland.

RESULTS

Taller subjects and those with better lung function had more favourable cardiovascular risk factor profiles, associations were strongest in relation to FEV(1). Higher FEV(1) was associated with lower blood pressure, cholesterol, glucose, fibrinogen, white blood cell count, and body mass index. Similar, but generally weaker, associations were seen with height. These associations were not attenuated in models controlling for parental height. Longer leg length, but not trunk length, was associated with lower systolic and diastolic blood pressure. Longer leg length was also associated with more favourable levels of cholesterol and body mass index than trunk length.

CONCLUSIONS

These findings provide indirect evidence that measures of lung development and pre-pubertal growth act as biomarkers for childhood exposures that may modify an individual's risk of developing CHD. Genetic influences do not seem to underlie height-CHD associations.

The long-term effect of dietary advice in men with coronary disease: follow-up of the Diet and Reinfarction trial (DART)

OBJECTIVE

To assess the long-term effect of dietary advice on diet and mortality after a randomised trial of men with a recent history of myocardial infarction.

DESIGN

Questionnaire survey and mortality follow-up after a trial of dietary advice.

SETTING

Twenty-one hospitals in south Wales and south-west England.

SUBJECTS

Former participants in the Diet and Reinfarction Trial.

MAIN OUTCOME MEASURES

Current fish intake and cereal fibre intake. All-cause mortality, stroke mortality and coronary mortality.

RESULTS

By February 2000, after 21147 person years of follow-up, 1083 (53%) of the men had died. Completed questionnaires were obtained from 879 (85%) of the 1030 men alive at the beginning of 1999. Relative increases in fish and fibre intake were still present at 10 y but were much smaller. The early reduction in all-cause mortality observed in those given fish advice (unadjusted hazard 0.70 (95% CI 0.54, 0.92)) was followed by an increased risk over the next 3 y (unadjusted hazard 1.31 (95% CI 1.01, 1.70). Fat and fibre advice had no clear effect on coronary or all-cause mortality. The risk of stroke death was increased in the fat advice group-the overall unadjusted hazard was 2.03 (95% CI 1.14, 3.63).

CONCLUSIONS

In this follow-up of a trial of intensive dietary advice following myocardial infarction we did not observe any substantial long-term survival benefit. Further trials of fish and fibre advice are feasible and necessary to clarify the role of these foods in coronary disease.