Mainstreaming in parallel with ovarian cancer tumor testing to improve genetic testing uptake

OBJECTIVES

Although genetic testing (GT) is universally recommended for patients with epithelial ovarian cancer (EOC), rates are low (34%). In 1/2019, we implemented mainstreaming-GT in parallel with tumor testing via MSK-IMPACT within oncology clinics. We sought to determine GT rates pre/post-mainstreaming and patient characteristics associated with GT.

METHODS

Patients with newly diagnosed EOC seen at our institution from 7/1/2015-3/31/2022 were included. Clinical data were abstracted including social determinants of health (SDOH) variables, race/ethnicity, marital status, insurance, language, comorbidities, employment, and Yost index, a measure of socioeconomic status. GT rates were calculated overall and pre-/post-mainstreaming (1/2019). Logistic regression models were fit to identify variables associated with GT.

RESULTS

Of 1742 patients with EOC, 1591 (91%) underwent GT. Rates of GT increased from 87% to 95% after mainstreaming (p < 0.001). Among 151 patients not undergoing GT, major reasons were lack of provider recommendation (n = 76, 50%) and logistical issues (n = 38, 25%) with few declining (n = 14, 9%) or having medical complications preventing GT (n = 7, 4.6%). High-grade serous histology, advanced stage (III/IV), and having a spouse/partner were associated with increased GT uptake (p < 0.01). Among SDOH variables, there were no differences by insurance, Yost score, language, comorbidities, employment, or race/ethnicity. In multivariable models, likelihood of GT increased with mainstreaming, even after adjustment for histology, stage, and marital status (OR 3.77; 95% CI: 2.56-5.66).

CONCLUSIONS

Mainstreaming increased the likelihood of GT in patients with EOC. We found lower testing rates in patients without partners/spouses, non-high-grade serous histology, and early-stage disease, representing potential areas for future interventions.

Obesity shapes selection for driver mutations in cancer

Obesity is a leading risk factor for cancer, but whether obesity is linked to specific genomic subtypes of cancer is unknown. Here, we examined the relationship between obesity and tumor genotype in two large clinicogenomic corpora. Obesity was associated with specific driver mutations in lung adenocarcinoma, endometrial carcinoma, and cancers of unknown primary, independent of clinical covariates and genetic ancestry. Obesity is therefore a putative driver of etiologic heterogeneity across cancers.

Tumor sequencing of African ancestry reveals differences in clinically relevant alterations across common cancers

Cancer genomes from patients with African (AFR) ancestry have been poorly studied in clinical research. We leverage two large genomic cohorts to investigate the relationship between genomic alterations and AFR ancestry in six common cancers. Cross-cancer type associations, such as an enrichment of MYC amplification with AFR ancestry in lung, breast, and prostate cancers, and depletion of BRAF alterations are observed in colorectal and pancreatic cancers. There are differences in actionable alterations, such as depletion of KRAS G12C and EGFR L858R, and enrichment of ROS1 fusion with AFR ancestry in lung cancers. Interestingly, in lung cancer, KRAS mutations are less common in both smokers and non-smokers with AFR ancestry, whereas the association of TP53 mutations with AFR ancestry is only seen in smokers, suggesting an ancestry-environment interaction that modifies driver rates. Our study highlights the need to increase representation of patients with AFR ancestry in drug development and biomarker discovery.

Abstract 4260: Understanding genomic and social determinants of cancer immunotherapy outcome across ancestry

Compared with previous standards of care, the use of immune checkpoint inhibitors (ICI) has brought significant improvements in survival and quality of life for lung cancer patients. However, only a small proportion of these patients respond durably. People with different ancestries differ probabilistically in genetic factors, environmental exposures, and socio-economic conditions. Whether patients of different ancestry benefit equally from ICIs remains unclear.

We studied the impact of genomic ancestry, tumor genomics, and social determinants of health (SDH) factors and factors that are impacted from SDH including recorded race/ethnicity, inferred low-income status from patient zip codes, exposure to smoking, and BMI on ICI response, defined by cancer progression-free survival (PFS, minimum 6 months FU), for non-small cell lung cancer (NSCLC) patients with MSK-IMPACT targeted panel sequencing. This FDA approved assay includes matched tumor-white blood cell sequencing to distinguish germline from somatic variants and has been applied to 1,802 NSCLC patients who received ICI treatment, including 81 and 117 patients with at least 80% of African (AFR) and East Asian (EAS) ancestry, respectively. Moreover, 173 samples were derived from admixed patients with more than one major ancestry.

We first used a natural language processing (NLP) model to obtain PFS from free-text clinical notes. A multivariable cox proportional hazard model was then used to associate PFS with ancestry, race, smoking status, ICI drug regimen, PD-L1 status, disease stage, tumor mutational burden (TMB), inferred income, and BMI. Neither genetic ancestry nor self-reported race/ethnicity was associated with the PFS. Moreover, ICI drug regimen types, low-income status, and BMI were not associated with PFS in our cohort. TMB-high was associated with longer PFS across all ancestries, although TMB was lower in patients with EAS ancestry (Median 7.9 vs. 5.3 mut/Mb, p&lt;0.001).

These results suggest that the benefits of ICI extend across ancestry, race, and income lines in a single institution, arguing for more equitable patient access to these medications. We also show that TMB is a generalizable biomarker for ICI outcome across ancestries. However, more diverse patient populations are needed to understand whether there is ancestry-specificity in other ICI outcome biomarkers.

Citation Format: Christopher J. Fong, Michele Waters, Karl Pichotta, Justin Jee, Devika R. Jutagir, David Ma, Tomin Perea-Chamblee, Susie Kim, Kanika Arora, Brooke Mastrogiacomo, Thinh Tran, Steven Maron, Mirella Altoe, Anisha Luthra, Joseph Kholodenko, Arfath Patha, Doori Rose, Michael F. Berger, Gregory J. Riely, Nikolaus Schultz, Sanna Goyert, Adam Schoenfeld, Francesca Gany, Jian Carrot-Zhang. Understanding genomic and social determinants of cancer immunotherapy outcome across ancestry. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 4260.

Abstract 5721: Automated annotation for large-scale clinicogenomic models of lung cancer treatment response and overall survival

The digitization of health records and prompt availability of tumor DNA sequencing results offer a chance to study the determinants of cancer outcomes with unprecedented richness; however, abstraction of key attributes from free text presents a major limitation to large-scale analyses. Using natural language processing (NLP), we derived sites of metastasis, prior treatment at outside institutions, programmed death ligand 1 (PD-L1) levels, and smoking status from records of patients with tumor sequencing to create a richly annotated clinicogenomic cohort. We sought to define whether combining features would improve models of overall survival (OS) and treatment response as validated in a multi-institution, manually curated cohort. We leveraged the manually curated AACR GENIE Biopharma Collaborative (BPC) dataset to train NLP algorithms to abstract the aforementioned features from overlapping records available at Memorial Sloan Kettering (MSK). All models achieved precision and recall &gt; 0.85. We deployed these algorithms to records of all MSK patients with non-small cell lung cancer (NSCLC) and tumor profiling with our FDA-authorized institutional targeted sequencing platform (N=7,015). These labels were combined with genomic, demographic, histopathologic, internal treatment and staging data to train random survival forests (RSF) to predict OS and time-to-next-treatment (TTNT) for molecularly targeted and immunotherapies. RSFs trained on the MSK NSCLC cohort were validated with the curated, non-MSK BPC NSCLC cohort (N=977). The addition of NLP-derived variables to genomic features enhanced RSF predictive power for OS (c-index, 10x bootstrap 95%CI: 0.58, 0.57-0.59 vs 0.75, 0.74-0.76 combined) and targeted and immunotherapy TTNT. The size of the MSK NSCLC cohort enabled discovery of associations between metastatic sites, PD-L1 status, genomics, and TTNTs not apparent in the smaller BPC cohort. We measured the added predictive value of variables not available in BPC with MSK-only cross-validation analyses. White blood cell differential counts and additional tissue genomic features including tumor mutational burden and fraction genome altered added minimally, while circulating tumor DNA sequencing added prognostic power for OS over other factors including disease burden

Using NLP we present a large NSCLC cohort with rich clinicoradiographic annotation, leading to superior models of patient outcomes. Our data uncovers associations not observed in smaller, manually curated cohorts and provides a foundation for further research in therapy choice and prognostication.

Citation Format: Justin Jee, Chris Fong, Karl Pichotta, Thinh Tran, Anisha Luthra, Mirella Altoe, Steven Maron, Ronglai Shen, Si-Yang Liu, Michele Waters, Joseph Kholodenko, Brooke Mastrogiacomo, Susie Kim, A Rose Brannon, Michael F. Berger, Axel Martin, Jason Chang, Anton Safonov, Jorge S. Reis-Filho, Deborah Schrag, Sohrab P. Shah, Pedram Razavi, Bob T. Li, Gregory J. Riely, Nikolaus Schultz. Automated annotation for large-scale clinicogenomic models of lung cancer treatment response and overall survival. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 5721.

Abstract A005: Genomic profiling identifies differences in the distribution of APC mutations in non-Hispanic black and non-Hispanic white patients with colorectal cancer

Intro: We compared molecular profiles of a large cohort of colorectal cancer patients treated at a single tertiary center to better understand the role of genomic factors for explaining differences in clinical outcomes of non-Hispanic black (NHB) vs. non-Hispanic white (NHW) patients. Methods: We analyzed targeted DNA sequencing data from 4,322 colorectal adenocarcinoma patients treated at Memorial Sloan Kettering Cancer Center, including 366 patients self-identified as NHB and 3,956 patients who self-identified as NHW. Tumors were sequenced using the MSK-IMPACT assay, a targeted sequencing platform that identifies somatic mutations, copy number changes, and gene fusions in a selected panel of 341-505 genes in tumor tissue compared to a matched normal blood sample. Genetic ancestry was estimated using reference populations from the 1000 Genomes Project, including European (EUR), African (AFR), East Asian (EAS), South Asian (SAS), and Native American (NAM). Patients were assigned specific ancestry labels when the corresponding ancestry fraction was above 80%. Results: Self-reported race and genetic ancestry were highly concordant, with 225/235, 95.7% of AFR patients self-reporting as NHB and 3215/3216, 99.96% of EUR patients self-reporting as NHW. While tumors from AFR patients were more often located in the right colon (43.27% vs. 30.56%, p&lt;0.001), they were also found to be less frequently microsatellite-instable (MSI) when compared to tumors from EUR patients (5.96% vs. 11.1%, p=0.026). Among right-sided cases, MSI tumors accounted only for 7.8% of AFR patients vs. 26.4% in EUR cases (p&lt;0.0001). Among MSS cases, tumors from AFR patients had a higher frequency of KRAS (59.1% vs. 44.7%, p&lt;0.0001) and SMAD2 (7.72% vs. 3.59%, p=0.006) mutations, as well as a lower frequency of BRAF mutations (3.18% vs. 7.22%, p=0.019). While the frequency of APC mutations was similar in both groups (77.45% vs. 72.98%, p=0.147), APC mutations in tumors from AFR patients were more frequently located within the C-terminal part of the protein (i.e., beyond the first 1400 amino acids), both when all tumors were analyzed together (50.0% vs. 38.5%, p=0.003) and when the analysis was restricted to non-hypermutated, microsatellite-stable (MSS) cases (48.0% vs. 35.5%, p=0.001). This higher frequency of C-terminal side mutations was also seen in self-reported Black/African American MSS colorectal cancer patients from AACR Project GENIE (58.9% vs 41.3%, p &lt; 0.001) and The Cancer Genome Atlas (61.1% vs 40%, p = 0.026). This type of distal APC mutations, which are considered “weak activators” of Wnt signaling, have been linked to more aggressive tumors due to concurrent activation of alternative mitogenic pathways such as ERK or PI3K. Conclusion: Some of the genomic differences between NHB and NHW patients that we had previously identified based on self-reported race were confirmed using analyses of genetic ancestry. We also present preliminary data demonstrating racial differences in the distribution of inactivating somatic mutations within the APC gene.

Citation Format: Henry Walch, Anisha Luthra, Walid Chatila, Kanika Arora, Samantha Chin, Michele Waters, Jesse J. Smith, Nikolaus Schultz, Michael F. Berger, Karuna Ganesh, Julio Garcia-Aguilar, Rona Yaeger, Francisco Sanchez-Vega. Genomic profiling identifies differences in the distribution of APC mutations in non-Hispanic black and non-Hispanic white patients with colorectal cancer [abstract]. In: Proceedings of the AACR Special Conference on Colorectal Cancer; 2022 Oct 1-4; Portland, OR. Philadelphia (PA): AACR; Cancer Res 2022;82(23 Suppl_1):Abstract nr A005.

Prevalence and predictors of inappropriate DOAC prescription on first attendance at a dedicated atrial fibrillation clinic

Introduction

Direct-acting oral anticoagulants (DOACs) are the preferred agents for stroke prevention in patients with non-valvular atrial fibrillation (AF). DOACs may require dose adjustment based on several factors, including: age, renal function and body weight. An inappropriate DOAC prescription is defined as a deviation of the drug specific recommended dose as mentioned in the summary of product characteristics. Inappropriate DOAC prescription may consist of both under- and over-dosing, potentially exposing patients to harm. Therefore, we carried out the current study, with the aim of defining the prevalence and predictors of inappropriate DOAC prescription on first attendance of patients at a specialist AF clinic.

Methods

We performed a retrospective analysis of the clinical database associated with a dedicated AF clinic in a large Irish hospital from August 2015 to March 2020. All new patients who were referred to the clinic and prescribed a DOAC prior to attendance were included. Data collected on patients included demographic and biochemical data in addition to clinical information on medical co-morbidities. In addition, the CHADS2VASc and HASBLED score was calculated for all patients. A multivariable logistic regression model was developed to assess for predictors of inappropriate DOAC dosing. Purposeful variable selection was used with univariate regression performed initially in order to identify predictors to include in the multivariable model.

Results

We included 367 patients in the analysis. An inappropriate DOAC dose was identified in 47 of 367 patients (12.8%). The majority of inappropriate DOAC doses were due to under-dosing (76.6%). Patients prescribed an inappropriate DOAC dose tended to be older (78.9±8.4 vs 69.0±10.5 years, p&lt;.001), with higher creatinine (108.5±4.6 vs 88.9±1.3, p&lt;.001). Patients prescribed an inappropriate DOAC dose also tended to have higher CHADS2VASc (3.8±1.7 vs 3.0±1.5, p=.001) and HASBLED scores (2.0±1.0 vs 1.6±1.0, p=.01) than patients prescribed an appropriate DOAC dose. DOAC choice did not differ between the inappropriate and appropriate DOAC dose groups. On univariate logistic regression analysis, several predictors of inappropriate DOAC prescription were identified, including age, renal function, history of falls, CHADS2VASc score and HASBLED score. However, in the multivariate logistic regression model, only increasing age (p&lt;0.001) and decreasing renal function (p&lt;0.001) remained significant predictors of inappropriate DOAC prescription.

Conclusions

Over one in eight patients (12.8%) are prescribed an inappropriate DOAC dose on first attendance at a dedicated atrial fibrillation clinic. In the majority of cases, the inappropriate DOAC prescription was secondary to under-dosing. In our multivariable, logistic regression model, increasing age and decreasing renal function were significant predictors of inappropriate DOAC prescription.

Funding Acknowledgement

Type of funding sources: None. Table 1

Age and the experience of strong self-conscious emotion

OBJECTIVES

It remains unclear whether there are age-related changes in the experience of strong self-conscious emotion, such as shame, guilt, pride and embarrassment. Because shame and guilt figure prominently in the aetiology of depressive symptoms and other mental health problems, a better understanding of how age affects the strong experience of these two negative self-conscious emotions is of particular importance.

METHODS

Thirty younger, 30 middle-aged and 30 older adults were compared on standardised cognitive assessments, in addition to an interview-based measure that assessed whether there are age differences in the likelihood of strongly experiencing four different types of self-conscious emotion within the past five years (shame, guilt, embarrassment and pride).

RESULTS

The three groups did not differ in their likelihood of reporting an event that strongly elicited the positive self-conscious emotion of pride. However, older adults were more likely to report sources of pride that were other (as opposed to self) focused. Older adults were also less likely to report experiencing events that elicited all three negative self-conscious emotions, in particular, shame.

CONCLUSIONS

Strong negative self-conscious emotion, and in particular shame, appears to be experienced less by older than younger adults.

Keratin biomaterials augment anti-inflammatory macrophage phenotype in vitro

Tissue regeneration following injury is mediated by macrophage recruitment and differentiation in response to environmental signals. In general, macrophages adopt either a classically M1 (M[IFN-γ, LPS]) or alternatively activated M2 (M[IL-4, IL-13] or M[IL-10]) phenotype. Recent studies have highlighted the importance of alternatively activated macrophages in tissue remodeling and repair as well as the contribution of an imbalance of classically and alternatively activated macrophages to tissue degeneration and disease progression. Keratin biomaterials have recently demonstrated their ability to promote alternatively activated macrophage polarization in an in vitro model using a monocytic cell line. In the present study, the ability of extracted human hair keratins to influence alternative activation of human primary monocytes in vitro is assessed by evaluating changes in surface receptor expression, inflammatory cytokine secretion, and phagocytic activity. The impact of keratin molecular weight fractionation on these outcomes was also investigated. High and low molecular weight fractions of the oxidized form of extractable human hair keratins - referred to as keratose (KOS^H and KOS^P, respectively) - were characterized by size exclusion chromatography, mass spectrometry, and Western blot. Primary macrophages underwent traditional differentiation to the M[IFN-γ, LPS], M[IL-4, IL-13], or M[IL-10]) phenotypes or were plated on different molecular weight keratin coatings (KOS^H and KOS^P). Macrophages plated on keratin and analyzed via flow cytometry yielded the largest CD163⁺ cell populations and CD163 mean fluorescence intensities. Cells in the KOS^P group were significantly more phagocytic than all other cell types at the 1.5 and 3 h time points and exhibited behavior and a cytokine production profile most similar to the M[IL-10] treated group. These findings may have important implications for understanding and evaluating the ability of keratin biomaterials to influence inflammation and tissue regeneration in disease and injury models.

STATEMENT OF SIGNIFICANCE

Biomaterials made from human hair keratins have previously been shown to elicit anti-inflammatory responses from naïve macrophages and polarize them toward an M2 phenotype. In this work we show for the first time that primary human cells respond similarly, that it is the M2c phenotype that predominates, that a sub-fraction of hydrolyzed keratin peptides are most likely responsible for the response, and that immobilization of the keratin peptides to a surface is required. Keratin biomaterials have been used to regenerate several tissues such as skin, muscle, bone, nerve, and cornea, in vitro and in animal studies. Our current findings will help guide the development of keratin-based biomaterials that seek to direct responses toward regenerative outcomes by attenuating inflammation.

Influence of surface roughness on silicone rubber voice prostheses on in vitro biofilm formation and clinical lifetime in laryngectomised patients

OBJECTIVES

Evaluation of the influence of a smooth surface moulding technique of silicone rubber indwelling voice prostheses on in vitro biofilm formation and analysis of the clinical in situ lifetime.

DESIGN

Biofilm formation on smooth and Groningen ultra low resistance (URL) prostheses was studied in an artificial throat model. The clinical lifetime of smooth voice prostheses was compared to the previous lifetime of URL by counting the number of replacements in a consecutive 6-month period in the same patient.

PARTICIPANTS

Eleven laryngectomised patients in follow-up who required frequent replacement of their voice prostheses.

SETTINGS

Tertiary University Medical Center.

RESULTS

Use of a smoother mould and less viscous silicone rubber yielded a decrease in surface roughness from 46 to 8 nm and was accompanied by a 40% reduction in the prevalence of bacteria and yeast in in vitro formed biofilms. Clinically, the lifetime was significantly (P<.005) increased by a factor of 2.1.

CONCLUSIONS

This combined in vitro and clinical study suggests that the choice of material and in particular its surface finishing may be determining factors with respect to the clinical lifetime of silicone rubber implants and devices failing due to biofilm formation.

Mcl-1 is a key regulator of the ovarian reserve

A majority of ovarian follicles are lost to natural death, but the disruption of factors involved in maintenance of the oocyte pool results in a further untimely follicular depletion known as premature ovarian failure. The anti-apoptotic B-cell lymphoma 2 (Bcl-2) family member myeloid cell leukemia-1 (MCL-1) has a pro-survival role in various cell types; however, its contribution to oocyte survival is unconfirmed. We present a phenotypic characterization of oocytes deficient in Mcl-1, and establish its role in maintenance of the primordial follicle (PMF) pool, growing oocyte survival and oocyte quality. Mcl-1 depletion resulted in the premature exhaustion of the ovarian reserve, characterized by early PMF loss because of activation of apoptosis. The increasingly diminished surviving cohort of growing oocytes displayed elevated markers of autophagy and mitochondrial dysfunction. Mcl-1-deficient ovulated oocytes demonstrated an increased susceptibility to cellular fragmentation with activation of the apoptotic cascade. Concomitant deletion of the pro-apoptotic Bcl-2 member Bcl-2-associated X protein (Bax) rescued the PMF phenotype and ovulated oocyte death, but did not prevent the mitochondrial dysfunction associated with Mcl-1 deficiency and could not rescue long-term breeding performance. We thus recognize MCL-1 as the essential survival factor required for conservation of the postnatal PMF pool, growing follicle survival and effective oocyte mitochondrial function.

Fluid shear stress induces the clustering of heparan sulfate via mobility of glypican-1 in lipid rafts

The endothelial glycocalyx plays important roles in mechanotransduction. We recently investigated the distribution and interaction of glycocalyx components on statically cultured endothelial cells. In the present study, we further explored the unknown organization of the glycocalyx during early exposure (first 30 min) to shear stress and tested the hypothesis that proteoglycans with glycosaminoglycans, which are localized in different lipid microdomains, respond distinctly to shear stress. During the initial 30 min of exposure to shear stress, the very early responses of the glycocalyx and membrane rafts were detected using confocal microscopy. We observed that heparan sulfate (HS) and glypican-1 clustered in the cell junctions. In contrast, chondroitin sulfate (CS), bound albumin, and syndecan-1 did not move. The caveolae marker caveolin-1 did not move, indicating that caveolae are anchored sufficiently to resist shear stress during the 30 min of exposure. Shear stress induced significant changes in the distribution of ganglioside GM1 (a marker for membrane rafts labeled with cholera toxin B subunit). These data suggest that fluid shear stress induced the cell junctional clustering of lipid rafts with their anchored glypican-1 and associated HS. In contrast, the mobility of CS, transmembrane bound syndecan-1, and caveolae were constrained during exposure to shear stress. This study illuminates the role of changes in glycocalyx organization that underlie mechanisms of mechanotransduction.

Reflections on the concept, conduct and findings of the producer-led Cicerone Project

The Cicerone Project began as a producer-led partnership that sought, over a period of 8 years, to enhance the profitability and sustainability of livestock enterprises by improving the connection between those producers, research and extension. Following a detailed survey, the research and extension needs of livestock producers were identified and several applied investigations were conducted to meet those needs and delivered through a range of extension activities. This final paper of the Cicerone Special Issue reflects on the entire Project from a wide array of perspectives, including livestock producers, researchers, extension specialists and staff employed by the Project, all of whom are authors of this paper. A notable early successful outcome of the Project was the improved precision of footrot diagnosis, which has been of value to the entire sheep industry, and that flowed from a field investigation of benign and virulent footrot combined with detailed genetic investigations, which led to an improved testing regime. This paper also reflects on the findings of an unreplicated agricultural ecosystem research trial, which measured the impact of pasture renovation, increased soil fertility and grazing management on the profitability and sustainability of three different 53-ha farmlets. Valuable findings from this whole-farmlet trial included the need for a high quality feed supply for increasing stocking rate and animal liveweights; the ability and utility of satellite imagery to detect changes in pasture growth, composition and recent grazing pressure; the value of short grazing and long rest periods for controlling Barber’s pole worms of sheep; the impact of increased stocking rates on whole-farm profitability and risk; methods of optimising decisions relating to pasture renovation, fertiliser applications and grazing management; and an integrated analysis of all key measured components of the farmlet management systems. Collectively, these findings were powerful as they were demonstrated at a scale credible to livestock producers using the ‘compare – measure – learn – adopt’ approach, which was the key philosophy adopted by the Cicerone Project. By comparing and measuring different whole-farm systems, and by ensuring that producers had ownership of the trial process, the Project successfully delivered objective findings that producers trusted and which increased our understanding of important drivers of complex grazing enterprises under variable climatic conditions. Some of these drivers included: the influence of soil phosphorus on botanical composition and subsequent livestock production, the role of pasture renovation and soil fertility on herbage supply, herbage quality and stocking rate, and the improved gastrointestinal nematode control delivered by intensive rotational grazing. The beneficiaries of the Project included the 180 farmer members who participated in some 61 field days and workshops; the research and extension collaborators including four postgraduates who completed their research investigations in conjunction with the Project; and some 500 undergraduate and 300 technical students who benefited from coming to understand the applied field comparisons of the three whole-farmlet systems. Having livestock producers play a significant leadership role led to valuable outcomes achieved with research collaborators; this should encourage the development of other learning partnerships which aim to explore complex farming system issues.

Second to fourth digit ratio and prostate cancer severity

BACKGROUND

The ratio of the second to the fourth digit (2D:4D ratio) is a sexually dimorphic trait established in utero that differs between ethnic groups. It is associated with prenatal androgen exposure, and studies have evaluated the ratio as a marker for certain traits and disease states known to be associated with higher levels of in utero androgens, such as prostate cancer. There are currently no screening tools that stratify men with prostate cancer according to the severity of their disease. This study aims to investigate the 2D:4D ratio as a potential marker for prostate cancer severity. Our hypothesis was that lower digit ratios, representing higher in utero androgen exposure, would be associated with more severe disease.

METHODS

Measurements were taken of the second and fourth digits of the right hand of male patients diagnosed with prostate cancer. Gleason score, presence of metastasis, family history, age at diagnosis and race were recorded. The distribution of demographic and other patient characteristics were compared with digit ratios to determine relationships.

RESULTS

African-American men with prostate cancer are 3.70 times more likely to have a low 2D:4D digit ratio than Caucasian men with prostate cancer (95% confidence interval: 1.98, 6.92; P < 0.0001). There were no statistically significant differences in the presence of metastasis, Gleason score, family history or age at diagnosis by digit ratio.

CONCLUSION

2D:4D ratio shows strong differences between African-Americans and Caucasians; however, it does not correlate with disease severity in men already diagnosed with prostate cancer. Although this is a small population sample with possible confounding factors, it does not provide evidence to support the hypothesis that prenatal androgens affect prostate cancer grade or progression.

Effect of a pathway bundle on length of stay

BACKGROUND

Pathways to guide clinical care are well accepted and used in many emergency departments. We wanted to introduce a number ("bundle") over a short space of time and involve the whole patient stay in the pathway. It was hypothesised that a more efficient process would result with an overall reduction in length of stay (LoS).

METHODS

A "bundle" of 14 evidence-based pathways of care was introduced into a medium-sized district general hospital (DGH) in late 2006/early 2007. These pathways covered emergency department care and acute medical care for a period of up to 48 h. A total of 8184 acute emergency admission episodes were audited, 3852 in the 8 months before introduction of the new pathways and 4332 in the 8 months after their introduction.

RESULTS

The overall effect of introducing the pathway bundle had a trend towards reduction in LoS by 0.2 days (95% CI -0.2 to 0.5), but this was not statistically significant (p>0.1). However, in those patients with </=2 diagnoses, the introduction of the pathway bundle had an independent effect in reducing LoS by 0.4 days (95% CI 0.04 to 0.7, p<0.01). In patients with </=2 diagnoses (63.0% of all pre-pathway cases and 63.4% of all post-pathway cases), the reduction in LoS equates to a saving of 2154 (CI 215 to 3769) bed days per annum or 5.9 (CI 0.6 to 10.3) beds saved each day. This reduced LoS represents an improvement of 2.5% (CI 0.25% to 4.38%) in medical bed usage. As this benefit occurs in the uncomplicated group of patients without multiple co-morbidities, such pathways would have the most effect in the type of patients who may be looked after by an emergency or acute physician. They are much less likely to be effective in those who require specialist intervention due to a more complicated presentation and possibly those with multiple co-morbidities.

CONCLUSION

The introduction of a bundle of evidence-based care pathways can modestly reduce LoS for certain types of acute medical patients in a DGH setting.

High serum concentrations of iron, transferrin saturation and gamma glutamyl transferase in captive black rhinoceroses (Diceros bicornis)

Iron storage disease (haemochromatosis) is thought to be the cause of many disorders unique to captive black rhinoceroses (Diceros bicornis). To establish reliable reference ranges for iron parameters, serum samples from 27 eastern black rhinoceroses (Diceros bicornis michaeli) from a translocation programme in Kenya were analysed and compared with the samples from 17 captive individuals. The transferrin saturation, serum iron concentration and gamma glutamyl transferase were significantly higher in the captive rhinoceroses, but these elevations were not evident when the results were compared with previously published data.

Graduate medical education in Ireland: a profile of the first cohort of students

BACKGROUND

The first graduate-entry programmes to Irish medicine were established at the Royal College of Surgeons in Ireland (RCSI) and the University of Limerick (UL) in 2007. There were over 400 applications across both institutions and 306 people sat a special aptitude test (GAMSAT) in Ireland in 2007. Ultimately, 61 Irish/EU students were admitted to one or other programme.

AIMS AND METHODS

We describe the demographic profile, academic background and aggregated GAMSAT performance of 306 people who sat GAMSAT in Ireland in 2007 and of the 61 people admitted to the RCSI/UL programmes.

RESULTS

While more females than males sat GAMSAT, slightly more males were admitted. Over 90% of those admitted were aged in their 20s, almost 20% had a higher degree and they came from a wide range of academic backgrounds.

CONCLUSIONS

Among others, this information should be of interest to prospective students and to government policy makers.

HIV-related knowledge and adherence to HAART

Near perfect adherence is considered essential for patients on HAART, yet adherence to medical recommendations is rarely so high. Supportive services and reminder tools may help individuals to become adherent, yet it is difficult to determine who may need such interventions. In this study, based on data from the NYSDOH/AIDS Institute Treatment Adherence Demonstration Program, we look at the association between HIV-related knowledge and adherence, hypothesizing that a better understanding of HIV and its treatment is associated with better adherence. In analyses based on 997 participants, knowledge, as measured by five true/false questions, was significantly associated with self-reported adherence. In multivariate analysis, compared to persons with four or five items answered correctly, persons with fewer correct answers were more likely to report missed doses (OR = 1.72 for 2-3 correct, p < 0.01; OR = 2.92 for 0-1 correct, p < 0.05). Our data suggest that providers should include questions focused on knowledge of HIV in their assessments of medication readiness and need for adherence support. Similarly, providers should be diligent with respect to patient education, ensuring that each patient has the information needed to support reasoned decision making and adequate adherence.

Childhood vaccination against varicella: persistence of antibody, duration of protection, and vaccine efficacy

OBJECTIVE

To document the duration of protection afforded by Oka/Merck varicella vaccine over a 7-year period.

STUDY DESIGN

The subjects were healthy children 1 to 12 years of age originally enrolled in clinical studies to evaluate the primary immune response to varicella vaccine 6 weeks after vaccination. Each was monitored for antibody persistence, breakthrough infection, and household exposure to varicella to produce estimates of vaccine efficacy.

RESULTS

The 6-year cumulative varicella antibody persistence rate was 99.5% (95% CI: 98.9%, 100.0%). The annual breakthrough rate through 7 years ranged from 0.2% to 2.3% per year; the estimated cumulative event rate was 6.5%. Comparison of the observed average annual breakthrough rate with the age-adjusted expected annual incidence rate of varicella in unvaccinated children corresponded to an estimated vaccine efficacy of 93.8% to 94.6%. Eighty vaccinated children were exposed to varicella in the household, resulting in 8 (10%) cases of infection. When compared with the historical attack rate of 86.8% in unvaccinated susceptible persons exposed to varicella in the household, this yields an estimated vaccine efficacy of 88.5% (95% CI: 80.9%, 96.1%). Varicella cases in vaccinated children generally were mild.

CONCLUSION

The live attenuated varicella vaccine is highly effective in inducing persistent immunity and long-term protection against breakthrough varicella infection.

Growth Hormone (GH)/GH Receptor Expression and GH-Mediated Effects During Early Bovine Embryogenesis1

Pituitary growth hormone (GH) stimulates postnatal growth and metabolism. The role of GH and its receptor (GHR) during prenatal development, however, is still controversial. As shown by reverse transcription polymerase chain reaction (RT-PCR), bovine in vitro fertilization embryos synthesized the transcript of GHR from Day 2 of embryonic life onwards. Real time RT-PCR revealed that synthesis of GHR mRNA was increased 5.9-fold in 6-day-old embryos compared with 2-day-old embryos. Using in situ hybridization, the mRNA encoding GHR was predominantly localized to the inner cell mass of blastocysts. The GHR protein was first visualized 3 days after fertilization. GH-specific transcripts were first detected in embryos on Day 8 of in vitro culture. As shown by transmission electron microscopy, GH treatment resulted in elimination of glycogen storage in 6- to 8-day-old embryos and an increase in exocytosis of lipid vesicles. These results suggest that a functional GHR able to modulate carbohydrate and lipid metabolism is synthesized during preimplantation development of the bovine embryo and that this GHR may be subject to activation by embryonic GH after Day 8.

Serum organochlorine levels and breast cancer: a nested case-control study of Norwegian women

This study investigated the potential association between organochlorine exposure and breast cancer using stored sera collected from 1973 through 1991 from the Janus Serum Bank in Norway. Breast cancer cases were ascertained prospectively from among 25,431 female serum bank donors. A total of 150 controls were matched to cases by birth dates and dates of sample collection. One g of serum per subject was analyzed for a total of 71 organochlorine compounds. For 6 pesticides [B-hexachlorocyclohexane, heptachlor epoxide, oxychlordane, trans-nonachlor, p, p'-1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene, and p, p'-2,2-bis(p-chlorophenyl)-1,1,1-trichloroethane] and 26 individual polychlorinated biphenyl (PCB) congeners there were >90% of samples over the limit of detection. There was no evidence for higher mean serum levels among cases for any of these compounds, nor any trend of increasing risk associated with higher quartiles of exposure. The remaining compounds (including dieldrin) were analyzed with respect to the proportion of cancer cases and controls having detectable levels; no positive associations were noted in these analyses. Our study did not confirm the recent findings of a Danish study of increased concentrations of dieldrin in the serum of breast cancer cases. The evidence to date on the association between serum organochlorines is not entirely consistent, but there is accumulating evidence that serum levels of p, p'-1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene and total PCBs are not important predictors for breast cancer in the general population. Studies to date have not been able to evaluate whether exposure to highly estrogenic, short-lived PCB congeners increases breast cancer risk, nor have they fully evaluated the risk associated with organochlorine exposure in susceptible subgroups or at levels above general population exposure, including women with occupational exposure.

The NIOSH/FAA Working Women's Health Study: evaluation of the cosmic-radiation exposures of flight attendants. Federal Aviation Administration

Air crew are exposed to elevated levels of cosmic ionizing radiation of galactic and solar origin and are among the more highly exposed occupational groups to ionizing radiation in the United States. Depending on flight route patterns, the annual dose may range from 0.2 to 5 mSv. By comparison, the average annual radiation dose equivalent of occupationally exposed adults in the United States is estimated to be 1.1 mSv. Cosmic-radiation dose depends primarily on altitude and geomagnetic latitude and to a lesser degree on solar activity. Although the International Commission on Radiological Protection has recommended that air crew exposures to natural radiation in-flight be treated as occupational exposures, United States flight crew exposures to natural cosmic radiation are not regulated or typically monitored. There are approximately 148,000 air crew (flight deck crew and flight attendants) in the United States.

Properties of an experimental mouthguard material

PURPOSE

The purpose of the present study was to evaluate some important mechanical properties of an experimental silicone material (PM1) to assess its potential as a mouthguard material.

MATERIALS AND METHODS

The hardness, tear strength, tensile properties, and energy absorption properties of the silicone material were determined and compared with those of 2 commercially available materials (Bioplast, a polyvinylacetate polyethylene, and Polyshield, a silicone).

RESULTS

Bioplast was significantly harder than Polyshield and PM1. Polyshield was significantly harder than PM1. Bioplast had a significantly higher tear strength than both Polyshield and PM1. The tensile strength of Bioplast was significantly greater than that of Polyshield and PM1. PM1 had a significantly higher tensile strength than Polyshield. Bioplast had a significantly lower energy absorption capacity at 500 N than both Polyshield and PM1, with PM1 having a significantly higher value than Polyshield. At 1,000 and 1,500 N, Bioplast had a significantly higher energy absorption than both Polyshield and PM1.

CONCLUSION

It was concluded that PM1 showed better energy absorption properties than Polyshield and better energy absorption properties than Bioplast at lower impact forces. PM1 was softer and had better tear and tensile properties than Polyshield. The results of the present study suggest that the new material has a good potential for use as a mouthguard material.

Optimisation of growth hormone production by muscle cells using plasmid DNA

The production of peptide hormones by skeletal muscle tissue is a promising area of gene therapy. Skeletal muscle myogenesis can be induced in vitro, resulting in the fusion of mononucleate myoblasts to form multinucleate myotubes, and delivery vectors are first tested in vitro. C2C12 myoblasts transfected with pcDNA3-GH, which used the human cytomegalovirus (CMV) promoter, secreted immunoreactive GH with comparable biological activity to pituitary GH. Mouse myeloid leukaemia cells, which express the mouse GH receptor were used for the bioassay, and activation of these cells by GH was measured by a colorimetric microculture tetrazolium assay. Cells were incubated with a tetrazolium salt (MTS) and an intermediate electron acceptor (phenazine methosulphate, PMS), and formazan production was measured as optical density (O.D.) at 490 nm. The efficiencies of several plasmid expression vectors were compared in differentiated and non-differentiated muscle cells, as a function of bioactive GH secreted by the transfected cells. Ten-day differentiated C2C12 myotubes transfected with pcDNA3E-GH, which used the CMV promoter and a rat myosin light chain enhancer element, secreted significantly more biologically active GH than myotubes transfected with pcDNA3-GH (0.82 O.D. units+/-0.06 vs 0.57+/-0.05 respectively, P<0.001). This was consistent with reduced CMV promoter activity in myotubes. Myoblasts transfected with pcDNA3-GH secreted more bioactive GH than 10-day transfected myotubes (1.1+/-0. 1 vs 0.77+/-0.07 respectively). However, the responses were indistinguishable (both 1.0+/-0.09) if both the myotubes and myoblasts had been transfected with pcDNA3E-GH. Substitution of the vector pMHLC-GH, which used a muscle-specific truncated rabbit myosin heavy chain promoter, and the myosin enhancer resulted in a marked decrease in the responses to the conditioned medium from fused myotubes compared with the vectors pcDNA3-GH and pcDNA3E-GH (0. 24+/-0.02 vs 0.57+/-0.05 vs 0.82+/-0.06 respectively). We concluded that the combination of CMV promoter and myosin light chain enhancer in pcDNA3E-GH had the greatest expression efficiency of the several plasmid vectors which we investigated.

Using molecular epidemiology in assessing exposure for risk assessment

Quantitative estimation of health risks depends on exposure characterization, the nature of the dose response relationships, and the toxicity of the agents involved. The greatest uncertainties in risk assessment almost always arise from sparse or inadequate exposure data, inadequate understanding of exposure mechanisms, and insufficient understanding of the exposure-dose-response pathway. Additional sources of uncertainty arise when mixed or multiple exposures are implicated in the disease pathway, and as a result of variability in both exposures and responses within and between individuals. Here we consider the role of exposure assessment in the risk assessment process, the use of biological markers or molecular epidemiology to contribute to improvements in exposure assessment for risk assessment, and uncertainties associated with the use of biological markers.

Improved wettability of an experimental silicone rubber denture soft lining material

The purpose of this study was to improve the wettability of an experimental silicone rubber soft lining material (Sildent) to increase patient comfort. Sildent was modified by the addition of polyalkylene oxide poly(dimethylsiloxane) surfactants. The various surfactants were added directly to the polymeric matrix in the quantities 5, 10, 20% w/w. The surfactants were also added to a one part silicone sealant, which was then painted onto the surface of already cured Sildent. Contact angle measurements were made on samples using a dynamic contact angle analyzer. Results showed that incorporation of surfactants A (Silwet L7600) and B (Silwet L7607) effectively improved the wettability of Sildent. This improvement was still evident after 6 months storage in distilled water at 37 degrees C suggesting retention of the surfactants matrix via physio-chemical bonding. Formulations with surfactants added directly to the matrix showed unacceptable water absorption after 2 months in distilled water. Samples with surfactant charged sealant painted on the surface showed a lower water absorption. In conclusion, Sildent formulations modified with polyalkylene silicone surfactants showed improved wettability compared to unmodified Sildent. Further work is needed to reduce water uptake and determine the effect on key mechanical properties.

Up-regulation of growth hormone receptor immunoreactivity in human melanoma

Growth hormone (GH) exerts its regulatory functions in controlling metabolism, balanced growth and differentiated cell expression by acting on specific receptors, which trigger a phosphorylation cascade resulting in the modulation of numerous signalling pathways, and dictate gene expression. Immunohistochemical techniques were used to demonstrate the presence of growth hormone receptors in 126 formalin-fixed, paraffin-embedded melanocytic tumours comprising melanocytic naevi, superficial spreading melanoma, nodular melanoma, lentigo maligna melanoma and metastatic melanomas. The relative proportion of positive cells and intensity of staining was higher in neoplastic cells, compared to normal cutaneous cells. Of the 76 cases of common melanocytic naevi (CMN) studies, 46 were weakly reactive with MAb 263. Heterogeneity of immunoreactivity was found in primary melanoma lesions with a variable range of positive cells. Of 37 cases studied, 34 were moderately to strongly positive. Immunoreactivity showed subcellular localization of the GH-receptor in cell membranes, was predominantly cytoplasmic, but strong nuclear immunoreaction was also apparent in many instances. The nuclear localization of immunoreactivity is the result of nuclear GH-receptor/binding protein, identically to the cytosolic and plasma growth hormone binding protein. Intense immuno-reactivity was also observed in the cellular Golgi area of established cell lines and cultured tissue-derived cells in exponential growth phase, indicating cells are capable of GH-receptor synthesis. In the primary lesions, dermal tumour cells tended to be more immunoreactive relative to those seen in the dermal region. Metastatic lesions in various organs also expressed growth hormone receptors in secondary tumour cells and all of the metastatic cases were positive. The expression of GH-receptors in human melanoma cells means that these cells are directly responsive to GH action and that GH may stimulate local production of IGF-I, which then acts in an autocrine mechanism.

Immunochemotherapy with interferon-gamma and multidrug therapy for multibacillary leprosy

Treatment for multibacillary leprosy is presently performed with a multidrug therapy (MDT) scheme maintained for 2 years. Leprosy treatment however can benefit from the reduction of length. The lack of interferon-gamma (IFN-gamma) production by lepromatous leprosy (LL) patients' lymphocytes lead us to use this cytokine in the treatment of multibacillary leprosy associated with MDT in the treatment of multibacillary leprosy, and monitor several clinical and immunological parameters during the course of treatment. A total of 20 multibacillary leprosy patients were evaluated, 10 treated with MDT alone, and 10 treated with MDT + 10 daily doses of 2 x 10(6) international units (IU) of recombinant human IFN-gamma/m2 followed by 10 daily doses of 10(7) IU IFN-gamma/m2, intramuscularly, during the first 20 days of MDT. IFN-gamma was well tolerated and did not cause any increase in the rate of leprosy reactions development during treatment. Decrease of bacillary load, fall of anti-Mycobacterium leprae IgG serum antibodies, changes of histological pattern, as well as changes in lymphocyte proliferation assay in response to mitogens (PHA or PWM), M. leprae antigen or PPD was similar in both groups of patients. Among several soluble immunological markers measured before and 30 days after beginning of treatment, levels of soluble IL-2R receptor increased in patients treated with MDT plus IFN-gamma whereas decreased in patients treated with MDT alone. Soluble ICAM-1 levels decreased in the MDT group but did not change in the MDT + IFN-gamma treated patients. Soluble CD4 and soluble CD8 markers did not change significantly in either group of patients. Neopterin, a marker of macrophage activation, increased in all but one patient treated with MDT + IFN-gamma but in none treated with MDT alone, indicating that IFN-gamma was active in vivo. Our findings indicate that despite being able to promote macrophage activation in multibacillary leprosy patients a short course of systemically administered IFN-gamma is not able to change the clinical course of a long standing disease such as leprosy.