Upper beak depression instead of elevation dominates cranial kinesis in woodpeckers

The value of birds' ability to move the upper beak relative to the braincase has been shown in vital tasks like feeding and singing. In woodpeckers, such cranial kinesis has been thought to hinder pecking as delivering forceful blows calls for a head functioning as a rigid unit. Here, we tested whether cranial kinesis is constrained in woodpeckers by comparing upper beak rotation during their daily activities such as food handling, calling and gaping with those from closely related species that also have a largely insectivorous diet but do not peck at wood. Both woodpeckers and non-woodpecker insectivores displayed upper beak rotations of up to 8 degrees. However, the direction of upper beak rotation differed significantly between the two groups, with woodpeckers displaying primarily depressions and non-woodpeckers displaying elevations. The divergent upper beak rotation of woodpeckers may be caused either by anatomical modifications to the craniofacial hinge that reduce elevation, by the caudal orientation of the mandible depressor muscle forcing beak depressions, or by both. Our results suggest that pecking does not result in plain rigidification at the upper beak's basis of woodpeckers, but it nevertheless significantly influences the way cranial kinesis is manifested.

Surface Potential Modulation in Boronate-Functionalized Magnetic Nanoparticles Reveals Binding Interactions: Toward Magnetophoretic Capture/Quantitation of Sugars from Extracellular Matrix

Phenylboronic acids (BAs) are important synthetic receptors that bind reversibly to cis-diols enabling their use in molecular sensing. When conjugated to magnetic iron oxide nanoparticles, BAs have potential for application in separations and enrichment. Realizing this will require a new understanding of their inherent binding modes and measurement of their binding capacity and their stability in/extractability from complex environments. In this work, 3-aminophenylboronic acid was functionalized to superparamagnetic iron oxide nanoparticles (MNPs, core diameter 8.9 nm) to provide stable aqueous suspensions of functionalized particles (BA-MNPs). The progress of sugar binding and its impact on BA-MNP colloidal stability were monitored through the pH-dependence of hydrodynamic size and zeta potential during incubation with a range of saccharides. This provided the first direct observation of boronate ionization pK_a in grafted BA, which in the absence of sugar shifted to a slightly more basic pH than free BA. On exposure to sugar solutions under MNP-limiting conditions, pK_a moved progressively to lower pH as maximum capacity was gradually attained. The pK_a shift is shown to be greater for sugars with greater BA binding affinity, and on-particle sugar exchange effects were inferred. Colloidal dispersion of BA-MNPs after binding was shown for all sugars at all pHs studied, which enabled facile magnetic extraction of glucose from agarose and cultured extracellular matrix expanded in serum-free media. Bound glucose, quantified following magnetophoretic capture, was found to be proportional to the solution glucose content under glucose-limiting conditions expected for the application. The implications for the development of MNP-immobilized ligands for selective magnetic biomarker capture and quantitation from the extracellular environment are discussed.

Abstract PO-032: Mechanistic studies of hypoxia as a driver of genomic instability in prostate cancer

Prostate cancer (PCa) is the 2nd most prevalent cancer in men and has poor patient outcome upon transition from localized disease to the castration-resistant and metastatic state. Numerous studies have indicated intratumoral hypoxia as a key driver in disease progression across multiple cancers and in prostate cancer. Hypoxia is associated with local recurrence, metastatic capacity, androgen independence and neuroendocrine differentiation (Ashton and Bristow, Brit.J.Rad, 2020). Crucially, among localized PCa patients, hypoxia and genomic instability have an independent and additive effect on biochemical relapse and bioinformatic studies suggest that hypoxia co-segregates mutation signatures representing defects in homologous recombination (HR) and mismatch repair (MMR) DNA repair pathways (Bhandari et al., Nat Comms, 2020). In order to investigate whether hypoxia directly drives genome instability in prostate cancer, mechanistic studies using hTERT-immortalized, primary prostate epithelial cells isogenic for c-MYC, BRCA2, or TP53/RB (SV40-transduced as PNT2 cells) were studied as to the relationship between hypoxia, inherent versus acquired genetic instability, and DNA repair capacity in-vitro and in-situ. Chronic hypoxia (20 generation doublings at 0.2% O2) was sufficient to drive increased copy number alterations (CNAs; based on low-pass whole genome sequencing - WGS) in selected clones by up to 30% in TP53/RB null cells, but not hTERT immortalized models. This finding is now being quantitated within a clonal evolution model and genotype-phenotype associations are being validated using functional transformation and invasion assays. Associated mechanistic studies have revealed that the hypoxic suppression of homologous recombination (HR) factor transcript and protein abundance (e.g up to ~60% reduction of RAD51/BRCA2 in PC3, DU145 and PNT2 cells) and associated with reduced RAD51 nuclear foci induction or defective DR-GFP reconstitution, is highly-dependent on cell density. This suggests that reduced HR and MMR repair capacity may exist in situ within hypoxic tumor oxygen gradients with close cell-cell interactions; in situ studies of RAD51 and other DNA repair proteins across hypoxic gradients in primary human tumors will be presented. These translational studies will accompany the HYPROGEN trial in Manchester in which patients who present with treatment-naïve M1 bone metastatic disease are given oral pimonidazole prior to prostate and bone metastasis biopsies to directly study genomic instability (using WGS) and hypoxia (pimonidazole staining and RNA hypoxic signatures) to understand these relationships in paired primary-metastatic samples. This data will provide a mechanistic basis for the adverse prognosis seen in patients whose tumors have both hypoxia and genome instability, as well as fresh evidence for stratification and treatment intensification of localized PCa patients with hypoxic tumors. (Supported by a core grant from Cancer Research UK to RGB)

Citation Format: Jack Ashton, Richard Rebello, Stephen Lyons, Robert G. Bristow. Mechanistic studies of hypoxia as a driver of genomic instability in prostate cancer [abstract]. In: Proceedings of the AACR Virtual Special Conference on Radiation Science and Medicine; 2021 Mar 2-3. Philadelphia (PA): AACR; Clin Cancer Res 2021;27(8_Suppl):Abstract nr PO-032.

Abstract PO-035: Understanding the role of hypoxia and PTEN loss in driving prostate cancer progression

Prostate cancer is the most commonly diagnosed cancer in the UK. Increased levels of prostate hypoxia have been shown to drive tumor aggression as an adverse prognostic factor following surgery or radiotherapy, especially when combined with tumor genetic instability. Our recent collaborative bioinformatic studies (Bhandari et al, Nat. Genetics 2019; Nat. Communications 2020) have shown various copy number changes to be enriched in hypoxic tumors, with mono- or bi-allelic loss of the PTEN being the most significant. To delineate a direct relationship between hypoxia and PTEN loss, we interrogated the impact of chronic hypoxia (1% O2, 0.2% O2; 72 h) on PTEN oncogenic signaling and asked whether this translates to improved fitness and survival in non-transformed and transformed PTEN isogenic cell lines. Despite increased oncogenic signaling (increased phospho-AKT) of PTEN-null 22Rv1 cells and hTERT-immortalized prostate epithelial cells (GHM) under chronic hypoxic gassing conditions, this did not lead to increased adaption and tumor clone survival. Differential survival for the PTEN isogenic cell lines following prostate cancer therapies (i.e. IR, PARPi, cDDP, taxols) under oxia and hypoxia are underway to further this work and determine a potential translational importance to clinical treatment. Independent evidence also points to hypoxia/PTEN loss in deregulating centrosome biology as a potential mechanism for genetic instability under hypoxia. Hence, we also hypothesized that the relationship between PTEN and hypoxia might be unearthed if aberrant unstable mitoses following deregulation of spindle poles under hypoxia selectively adapt and have a survival advantage. Quantitative immunofluorescence of centrosome aberrations, using antibodies to phospho-Histone H3 and Centrin-1, show significant increases in centriole numbers (p < 0.05) in mitotic cells under chronic hypoxic conditions and an increase in the incidence of micronuclei (p < 0.005), specifically in chronic hypoxic cells with PTEN loss, supporting our hypothesis. Current studies are investigating in situ staining of centrosomes as a readout of chromosomal instability (CIN) in primary prostate cancer tissues with variable PTEN status as a new biomarker for aggressiveness to link hypoxia-associated genetic instability with novel clinical trial development. (Funded by Cancer Research UK as a core grant to RGB).

Citation Format: Alexandru Suvac, Richard Rebello, Stephen Lyons, Robert G. Bristow. Understanding the role of hypoxia and PTEN loss in driving prostate cancer progression [abstract]. In: Proceedings of the AACR Virtual Special Conference on Radiation Science and Medicine; 2021 Mar 2-3. Philadelphia (PA): AACR; Clin Cancer Res 2021;27(8_Suppl):Abstract nr PO-035.

Correction: Electrostatically modulated magnetophoretic transport of functionalised iron-oxide nanoparticles through hydrated networks

Correction for 'Electrostatically modulated magnetophoretic transport of functionalised iron-oxide nanoparticles through hydrated networks' by Stephen Lyons et al., Nanoscale, 2020, 12, 10550-10558, DOI: 10.1039/D0NR01602K.

β Decay of ^{61}V and its Role in Cooling Accreted Neutron Star Crusts

The interpretation of observations of cooling neutron star crusts in quasipersistent x-ray transients is affected by predictions of the strength of neutrino cooling via crust Urca processes. The strength of crust Urca neutrino cooling depends sensitively on the electron-capture and β-decay ground-state-to-ground-state transition strengths of neutron-rich rare isotopes. Nuclei with a mass number of A=61 are predicted to be among the most abundant in accreted crusts, and the last remaining experimentally undetermined ground-state-to-ground-state transition strength was the β decay of ^{61}V. This Letter reports the first experimental determination of this transition strength, a ground-state branching of 8.1_{-3.1}^{+4.0}%, corresponding to a log ft value of 5.5_{-0.2}^{+0.2}. This result was achieved through the measurement of the β-delayed γ rays using the total absorption spectrometer SuN and the measurement of the β-delayed neutron branch using the neutron long counter system NERO at the National Superconducting Cyclotron Laboratory at Michigan State University. This method helps to mitigate the impact of the pandemonium effect in extremely neutron-rich nuclei on experimental results. The result implies that A=61 nuclei do not provide the strongest cooling in accreted neutron star crusts as expected by some predictions, but that their cooling is still larger compared to most other mass numbers. Only nuclei with mass numbers 31, 33, and 55 are predicted to be cooling more strongly. However, the theoretical predictions for the transition strengths of these nuclei are not consistently accurate enough to draw conclusions on crust cooling. With the experimental approach developed in this work, all relevant transitions are within reach to be studied in the future.

New ^{13}C(α,n)^{16}O Cross Section with Implications for Neutrino Mixing and Geoneutrino Measurements

Precise antineutrino measurements are very sensitive to proper background characterization. We present an improved measurement of the ^{13}C(α,n)^{16}O reaction cross section which constitutes significant background for large ν[over ¯] detectors. We greatly improve the precision and accuracy by utilizing a setup that is sensitive to the neutron energies while making measurements of the excited state transitions via secondary γ-ray detection. Our results shows a 54% reduction in the background contributions from the ^{16}O(3^{-},6.13  MeV) state used in the KamLAND analysis.

Electrostatically modulated magnetophoretic transport of functionalised iron-oxide nanoparticles through hydrated networks

Factors that determine magnetophoretic transport of magnetic nanoparticles (MNPs) through hydrated polymer networks under the influence of an external magnetic field gradient were studied. Functionalised iron oxide cores (8.9 nm core diameter) were tracked in real-time as they moved through agarose gels under the influence of an inhomogeneous magnetic field. Terminal magnetophoretic velocities were observed in all cases, these were quantified and found to be highly reproducible and sensitive to the conditions. Increasing agarose content reduced magnetophoretic velocity, we attribute this to increasingly tortuous paths through the porous hydrated polymer network and propose a new factor to quantify the tortuosity. The impact of MNP surface functionalisation, charge, network fixed charge content, and ionic strength of the aqueous phase on velocity were studied to separate these effects. For MNPs functionalised with polyethylene glycol (PEG) increasing chain length reduced velocity but the tortuosity extracted, which is a function of the network, was unchanged; validating the approach. For charged citrate- and arginine-functionalised MNPs, magnetophoretic velocities were found to increase for particles with positive and decrease for particles with negative zeta potential. In both cases these effects could be moderated by reducing the number of agarose anionic residues and/or increasing the ionic strength of the aqueous phase; conditions under which tortuosity again becomes the critical factor. A model for MNP transport identifying the contributions from the tortuous pore network and from electrostatic effects associated with the pore constrictions is proposed.

Abstract P5-09-06: Underdiagnosis of HBOC in breast cancer patients: Are genetic testing guidelines a tool or an obstacle?

Background: Pathogenic genetic variants are estimated to occur in 10-15% of all breast cancer patients, with BRCA 1/2 accounting for 40-50% of pathogenic/likely pathogenic (P/LP) variants. However, it is estimated that <30% of breast cancer patients harboring a BRCA 1/2 variant have been identified, with the percentage being much less for ˜20 other breast cancer associated genes. Reasons for this are multifactorial and include complicated and restrictive testing guidelines developed at a time when the cost of testing was high and guidelines for management were limited. Today, cost has plummeted and there are definitive management guidelines for a broader range of genes. We created a community based Registry to determine the incidence of P/LP variants in breast cancer patients who meet and who do not meet the NCCN 2017 genetic testing criteria.

Methods: An IRB-approved multicenter prospective registry was initiated with 20 community and academic sites experienced incancer genetic testing and counseling.

Eligibility criteria included patients with a breast cancer diagnosis who had not been previously tested. Consecutive patients aged 18-90 were consented and underwent an 80 gene panel test (Invitae –Multi-Cancer Panel). The non-inferiority study was powered to detect a difference in P/LP variant rate of 4 percentage points with statistical significance (p<0.05, Fisher's exact test).

HIPAA compliant electronic case report forms collected information on patient diagnosis, test results, and physician recommendations made after test results were received.

Results: Over 1000 patients were enrolled and data from 910 subjects analyzed to date. 50.4% met NCCN criteria and 49.5% did not. Median age for the enrolled patients is 60.5 and ranged from 22-93. 56.0% of patients were recently diagnosed with breast cancer. 10.9% of patients had a history of a prior non breast cancer. Overall, 8.9% of patients had a pathogenicvariant. 9.6% of patients who met NCCN criteria with test results had a P/LP variant. 8.2% of patients who did not meet criteria had a P/LP variant. The difference of positive cases among the two groups is not statistically significant (P = 0.49)

4.9% of patients had pathogenic variants if only an 11 gene standard breast cancer panel was considered.

The spectrum of mutated genes varied between the two groups, with some overlap.

Conclusions:

There was no statistically significant difference in the number of pathogenic/likely pathogenic variants between those patients who met and those who did not meet NCCN guidelines. Expanded panel testing yields more medically actionable P/LP variants than testing BRCA 1/2 alone or breast cancer panels with 11 genes. This study demonstrates that there will be a significant number of patients with P/LP variants are missed if NCCN guidelines are required for genetic testing. Current NCCN guidelines for the genetic testing of breast cancer patients are an obstacle to identifying patients with P/LP variants and should be removed.

Universal BC Genetic Testing RegistryNCCN Criteria (910 patients analyzed)#/% who have P/LP variants#/% who do not have P/LP variantsPatients who meet guidelines44/459 (9.6%)415/459 (90.4%)Patients who do not meet guidelines37/451 (8.2%)414/451 (91.8%)

Citation Format: Beitsch P, Whitworth P, Baron P, Rosen B, Compagnoni G, Simmons R, Smith LA, Holmes D, Brown E, Gold L, Clark P, Coomer C, Grady I, Barbosa K, Riley L, Kinney M, Lyons S, MacDonald H, Kahn S, Ruiz A, Patel R, Curcio L, Esplin E, Yang S. Underdiagnosis of HBOC in breast cancer patients: Are genetic testing guidelines a tool or an obstacle? [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P5-09-06.

Abstract P5-09-03: Expanded panel testing superior to BRCA1/2 and breast cancer panel in patients with breast cancer

Background: The testing of hereditary breast and ovarian cancer (HBOC) patients for BRCA1/2 only was established years ago to identify patients with clinically actionable variants and limit the economic burden. However, the cost of genetic testing has plummeted, and the number of breast cancer-risk genes with management guidelines has expanded. We created a community-based registry to test all breast cancer patients. A primary objective of this registry included accruing and comparing patients who did and did not meet NCCN guidelines and determining if providing all breast cancer patients with comprehensive multi-gene panel testing yields additional clinical value than testing BRCA1/2 alone.

Methods: An IRB-approved multicenter prospective registry was initiated with 20 community-based and academic breast sites, selected to insure geographic and ethnic diversity. Consecutive patients ages 18-90 with current or prior breast cancer were offered testing with an 80-gene panel (Invitae, San Francisco, CA). HIPAA-compliant case report forms collected patient diagnosis, test results, and physician recommendations made after test results.

Results: Over 1,000 patients were enrolled and data on 911 have been analyzed to date. Median age of patients is 60.5 (range 22 to 93). 56.0% were recently diagnosed with breast cancer. Of these patients, 50.54% met NCCN criteria, and 49.5% did not. 10.9% had history of a prior non-breast cancer. The pathogenic/likely pathogenic (P/LP) variant rate for patients on a comprehensive 80-gene panel was 8.9%. When restricted to a guidelines-based 11-gene breast cancer panel (BRCA1/2, ATM, CDH1, CHEK2, NBN, NF1, PTEN, STK11, TP53, PALB2), 4.9% had P/LP variants; when limited to BRCA1/2, 1.6% had P/LP variants. Of all patients with P/LP findings, 93% had variants in cancer-risk genes with established management recommendations (Table 1) and 80% had germline variants conferring eligibility for precision medicine-based cancer treatments, such as PARP inhibitors, through actively enrolling clinical trials.

Conclusions: This study demonstrates that comprehensive panel testing of breast cancer patients provides a higher yield of clinically actionable P/LP variants than BRCA1/2 testing alone. Limited panels may miss clinically relevant P/LP variants, leaving risk for preventable cancers undiscovered and unnecessarily restricting patients' treatment options. These results also suggest that variants in tumor suppressor genes, not previously thought related to breast cancer, may contribute to its etiology. A comprehensive panel strategy reveals untapped clinical utility and can impact breast cancer patient care by informing implementation of precision medicine treatment interventions and guiding long-term medical management and surveillance for patients and their family members.

 PatientsVariantsWith breast cancer management guidelines (including variants ATM*, BRCA1*, BRCA2*, CHEK2*, NBN*, NF1, PALB2*, TP53*)45 (56%)46 (55%)With cancer guidelines and clinical management implications (including variants BARD1*, FH, MITF, MSH6*, MUTYH*, PTCH1, RAD50*, RAD51C*, RAD51D*, RB1, RET, VHL)31 (38%)33 (39%)Evidence of actionability accruing (including variants BLM, DIS3L2, RECQL4)5 (6%)5 (6%)Totals8184*P/LP variants in these genes confer potential clinical trial eligibility, e.g. NCT02401347.

Citation Format: Beitsch P, Whitworth P, Baron P, Rosen B, Compagnoni G, Simmons R, Smith LA, Holmes D, Brown E, Gold L, Clark P, Coomer C, Grady I, Barbosa K, Riley L, Kinney M, Lyons S, MacDonald H, Kahn S, Ruiz A, Patel R, Curcio L, Esplin E, Yang S, Michalski S. Expanded panel testing superior to BRCA1/2 and breast cancer panel in patients with breast cancer [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P5-09-03.

The association between psychological factors and breastfeeding behaviour in women with a body mass index (BMI) ≥30 kg m-2 : a systematic review

Breastfeeding can play a key role in the reduction of obesity, but initiation and maintenance rates in women with a body mass index (BMI) of ≥30 kg m^-2 are low. Psychological factors influence breastfeeding behaviours in the general population, but their role is not yet understood in women with a BMI ≥30 kg m^-2 . Therefore, this review aimed to systematically search and synthesize the literature, which has investigated the association between any psychological factor and breastfeeding behaviour in women with a BMI ≥30 kg m^-2 . The search identified 20 eligible papers, reporting 16 psychological factors. Five psychological factors were associated with breastfeeding behaviours: intentions to breastfeed, belief in breast milk's nutritional adequacy and sufficiency, belief about other's infant feeding preferences, body image and social knowledge. It is therefore recommended that current care should encourage women to plan to breastfeed, provide corrective information for particular beliefs and address their body image and social knowledge. Recommendations for future research include further exploration of several psychological factors (i.e. expecting that breastfeeding will enhance weight loss, depression, anxiety and stress) and evidence and theory-based intervention development.

Experimental measurement of the 12C+16O fusion cross sections at astrophysical energies

The total cross sections of the 12C+16O fusion have been experimentally determined at low energies to investigate the role of this reaction during late stellar evolution burning phases. A high-intensity oxygen beam was produced by the 5MV pelletron accelerator at the University of Notre Dame impinging on a thick ultra-pure graphite target. Protons and γ-rays were measured simultaneously in the center-of-mass energy range from 3.64 to 5.01 MeV, using strip silicon and HPGe detectors. Statistical model calculations were employed to interpret the experimental results. A new broad resonance-like structure is observed for the 12C+16O reaction, and a decreasing trend of its S-factor towards low energies is found.

JNK suppresses tumor formation via a gene-expression program mediated by ATF2

JNK and p38 phosphorylate a diverse set of substrates and, consequently, can act in a context-dependent manner to either promote or inhibit tumor growth. Elucidating the functions of specific substrates of JNK and p38 is therefore critical for our understanding of these kinases in cancer. ATF2 is a phosphorylation-dependent transcription factor and substrate of both JNK and p38. Here, we show ATF2 suppresses tumor formation in an orthotopic model of liver cancer and cellular transformation in vitro. Furthermore, we find that suppression of tumorigenesis by JNK requires ATF2. We identify a transcriptional program activated by JNK via ATF2 and provide examples of JNK- and ATF2-dependent genes that block cellular transformation. Significantly, we also show that ATF2-dependent gene expression is frequently downregulated in human cancers, indicating that amelioration of JNK-ATF2-mediated suppression may be a common event during tumor development.

Content analysis of newspaper reports on alcohol-related deaths

AIM

International research indicates that the role which alcohol plays in accidents tends to be understated in media reports. Evidence suggests that public support for alcohol harm reduction policies would increase if people were better informed about the role of alcohol in serious injuries. We hypothesized that the role of alcohol in Irish accidental deaths is under-reported in the Irish print media.

METHOD

We identified all traumatic and poisoning deaths (excluding suicides) in Ireland during the years 2008 and 2009 where alcohol was mentioned on the death certificate. We conducted an Internet-based search for newspaper reports of these deaths. The content of each report was examined and rated for mention of alcohol's possible role in the individual death.

RESULTS

This study demonstrates the under-reporting in Irish newspapers of the role of alcohol in traumatic and poisoning deaths. Where deaths were reported, the role played by alcohol was generally ignored.

CONCLUSION

This represents a missed opportunity to inform the public about the role of alcohol in these deaths. More accurate information would permit the public to make more informed decisions regarding their own behaviour and regarding their support for alcohol harm-reducing strategies.

Exercise intensity and lymphocyte subset apoptosis

This investigation assessed the lymphocyte subset response to increasing intensity. Participants completed an exertion test (VO(2max)), and later performed a 10-min run at 76% VO(2max), 5-min at 87%, and run to exhaustion at 100% intensity. Blood was sampled at rest, following each intensity, and 1-h post. Cell concentration, apoptosis (annexin V) and migration (CX₃CR1) were evaluated in CD4+, CD8+, and CD19+ subsets. Relative data were analyzed using 1-way ANOVA with significance at P≤0.05. Absolute changes from rest (Δ baseline) were calculated for exercise conditions. CX₃CR1 displayed relative changes 1-h post, (CD8+ Pre=58%, Post=68%, 1 h-Post=37%, P=0.04) (CD19+ Pre=1.9%, Post=3.2%, 1 h-Post=5.2%, P=0.02). No relative changes were noted for subsets and annexin V. Absolute changes revealed that CD4+/annexin V+ and CD8+/annexin V+ significantly increased at 76%,(P<0.01). Significant absolute increases were observed in CD4+/CX₃CR1 at 87% VO2max, and at 87% and 100% VO2max in CD8+/CX₃CR1 (P<0.01). Subsets respond differently with intensity with respect to cell count, and markers of apoptosis and cell migration. CD4+ and CD8+ appear to be prone to apoptosis with moderate exercise, but significant increases in migration at higher intensities suggests movement of these cells from the vasculature in postexercise measurements.

Asymmetrical attenuation of vibration sensation in unilateral diabetic Charcot foot neuroarthropathy

AIMS

To further characterize the distal sensory neuropathy in subjects with unilateral diabetic Charcot foot neuroarthropathy.

METHODS

A retrospective cohort study to assess the level to which the sensory modalities of pinprick, light touch, vibration, joint position and temperature were attenuated in the affected and unaffected limbs in subjects with unilateral Charcot. The level to which the sensory modality was attenuated in each limb was assigned a score. The Wilcoxon signed rank test was used to compare the scores in the affected and unaffected limbs and also to compare the scores of the different sensory modalities in the affected and unaffected limbs.

RESULTS

Fifty subjects with unilateral Charcot foot neuroarthropathy were assessed. Mean age was 45 ± SD 6 years for the 17 subjects with Type 1 diabetes and 62 ± 10 years for the 33 subjects with Type 2 diabetes. Duration of diabetes was 21 ± 13 years, HbA(1c) was 70 ± 19 mmol/mol [8.6 ± 1.8 %] and 15 subjects (30%) required renal replacement therapy. The level of attenuation of vibration sensation was more proximal in the affected compared with the unaffected limbs (P = 0.002). Pinprick, light touch, joint position and temperature sensations were not different. Joint position sensation was less attenuated bilaterally than the other sensory modalities.

CONCLUSIONS

Asymmetrical attenuation of vibration sensation may predict the side that will develop a Charcot joint and may suggest a more important role for vibration sense loss than loss of other sensory modalities in the pathophysiology of Charcot.

Estimating the extra cost of living for people with disabilities

Addressing the extra economic costs of disability is a logical step towards alleviating elements of social exclusion for people with disabilities. This study estimates the long-run economic cost of disability in Ireland in terms of the additional spending needs that arise due to disability. It defines and estimates models of the private costs borne by families with individuals who have a disability in Ireland when compared with the wider population, both in general and by severity of disability. Our modelling framework is based on the standard of living approach to estimating the cost of disability. We extend on previous research by applying panel ordered probit models to living in Ireland survey data 1995-2001 in order to control for the effects of previous disability and income and correlated unobserved heterogeneity. The approach allows us to quantify, for the first time, the additional long-run economic costs of living associated with disability. Our findings suggest that the extra economic cost of disability in Ireland is large and varies by severity of disability, with important implications for measures of poverty.

Matching the numerator with an appropriate denominator to demonstrate low amputation incidence associated with a London hospital multidisciplinary diabetic foot clinic

AIMS

To establish a method to assess amputation incidence that addresses the problems matching a numerator with an appropriate denominator in London and to demonstrate low amputation incidence associated with the activity of our multidisciplinary diabetic foot clinic.

METHODS

Hospital-coded inpatient data was examined to derive the numerator: the number of non-traumatic amputations performed on subjects with diabetes each financial year where the Primary Care Trust commissioner code was our main local Primary Care Trust. Denominators were derived from the main local Primary Care Trust's Quality and Outcomes Framework data sets. Not all Primary Care Trust subjects with diabetes receive inpatient care at our hospital, so that the denominators were corrected for the hospital's percentage market share for the provision of inpatient diabetes care for the Primary Care Trust each financial year, derived from the Dr Foster database.

RESULTS

Between April 2004 and April 2009, 44 Primary Care Trust subjects with diabetes underwent 34 minor and 10 major amputations at the hospital. Although the Primary Care Trust populations with and without diabetes increased, the hospital's Primary Care Trust percentage market share decreased, so that overall denominators decreased. The mean annual incidence of minor, major and total amputations over the five financial years was 14.7, 4.2 and 18.9 per 10 000 subjects with diabetes,respectively, and 3.9, 1.1 and 5.0 per 100 000 of the general population, respectively.

CONCLUSIONS

We report for the first time amputation incidence in a London population. Acknowledging the limitations of accurately defining incidence in London, we demonstrate low amputation incidence associated with our multidisciplinary diabetic foot clinic.

Excess post-exercise oxygen consumption in untrained men following exercise of equal energy expenditure: comparisons of upper and lower body exercise

AIM

This study assessed excess post-exercise oxygen consumption (EPOC) following continuous 200- kcal bouts of upper body exercise (UBE) and lower body exercise (LBE).

METHODS

Ten untrained men (age: 25.7 +/- 5.83 years; arm VO(2peak): 2.2 +/- 0.25 l/min; 21.5 +/- 4.35 ml/kg/min; leg VO(2peak): 3.1 +/- 0.38 l/min; 30.7 +/- 7.79 ml/kg/min) exercised at 60% mode-specific VO(2) peak using either an arm crank or a leg cycle protocol (counterbalanced order with 48 h between). Baseline VO(2) was monitored for 30 min. EPOC was measured until baseline was re-established.

RESULTS

EPOC magnitude and duration were significantly greater (p < 0.05) following LBE (2.93 +/- 1.4 l/min; 16.5 +/- 7.4 min) compared with UBE (1.89 +/- 0.7 l/min; 11.5 +/- 6.1 min).

CONCLUSIONS

Results indicate that leg exercise elicited a greater EPOC magnitude and duration compared with arm exercise of the same relative intensity and energy expenditure.

Implications of the International Health Regulations (2005) for communicable disease surveillance systems: Tunisia's experience

BACKGROUND

In May 2005, the revised International Health Regulations, known as IHR (2005), were adopted in response to the evolving nature of communicable diseases (CD) and the rapid increase in global trade and travel. CD surveillance is an integral part of a country's core requirements under the regulations.

METHODS

The implications of these requirements were assessed as part of a review of the national CD surveillance system of Tunisia using a qualitative methodology of strengths, weaknesses, opportunities and threats (SWOT).

RESULTS

Tunisia is some way towards meeting the requirements of IHR (2005) while some specific areas that need to be addressed are highlighted for improvement: standardization of surveillance documents, strengthening the role of the laboratory in surveillance, increased human resources and training.

CONCLUSIONS

Tunisia's experience can offer some lessons to other countries in this process. While meeting the capacity obligations of IHR (2005) requires investment and commitment, this investment will enable countries to better protect themselves against public health emergencies arising within their borders and threatening from elsewhere in the world.

Development of luciferase tagged brain tumour models in mice for chemotherapy intervention studies

The blood-brain barrier (BBB) is considered one of the major causes for the low efficacy of cytotoxic compounds against primary brain tumours. The aim of this study was to develop intracranial tumour models in mice featuring intact or locally disrupted BBB properties, which can be used in testing chemotherapy against brain tumours. These tumours were established by intracranial injection of suspensions of different tumour cell lines. All cell lines had been transfected with luciferase to allow non-invasive imaging of tumour development using a super-cooled CCD-camera. Following their implantation, tumours developed which displayed the infiltrative, invasive or expansive growth patterns that are also found in primary brain cancer or brain metastases. Contrast-enhanced magnetic resonance imaging showed that the Mel57, K1735Br2 and RG-2 lesions grow without disruption of the BBB, whereas the BBB was leaky in the U87MG and VEGF-A-transfected Mel57 lesions. This was confirmed by immunohistochemistry. Bioluminescence measurements allowed the visualisation of tumour burden already within 4 days after injection of the tumour cells. The applicability of our models for performing efficacy studies was demonstrated in an experiment using temozolomide as study drug. In conclusion, we have developed experimental brain tumour models with partly disrupted, or completely intact BBB properties. In vivo imaging by luciferase allows convenient follow-up of tumour growth and these models will be useful for chemotherapeutic intervention studies.

An audit of thrombophilia screens: results from the National Pathology Alliance benchmarking review

AIMS

The National Pathology Alliance benchmarking review has completed six years of data collection and analysis of the workload and organisation of haematology laboratories in the UK. This study audits national practice of routine thrombophilia screening against the current standards, as set out in the British committee for standards in haematology (BCSH) guidelines on investigation of heritable thrombophilia.

METHODS

Each laboratory completed a standard data collection questionnaire about the number of routine thrombophilia assays performed each year. Information was collected on which thrombophilia tests were performed as part of a routine thrombophilia screen. These results were then compared against the BCSH guidelines on investigation of heritable thrombophilia.

RESULTS

Of the 57 National Health Service trusts that submitted data for review in 2002/2003, 47 performed a routine thrombophilia screen. Ten laboratories complied with the guidelines but 37 laboratories did not.

CONCLUSION

There was variation in practice in the tests used in routine thrombophilia screens. There is evidence that some laboratories deviate from what may be regarded as "evidence based practice". The lack of compliance with the guidelines was in general associated with the performance of additional tests not recommended in the guideline. In a minority of laboratories, a clinically significant diagnosis would be missed by the failure to include one or more tests in a thrombophilia screen.

MBP-annexin V radiolabeled directly with iodine-124 can be used to image apoptosis in vivo using PET

A noninvasive method of measuring programmed cell death in the tumors of cancer patients using positron-emission tomography (PET) would provide valuable information regarding their response to therapeutic intervention. Our strategy is to radiolabel annexin V, a protein that binds to phosphatidylserine moieties that are translocated to the external leaflet of plasma membranes during apoptosis. We developed a phosphatidylserine-ELISA capable of distinguishing wild type from point mutant annexin V that is known to have a lower phosphatidylserine binding affinity. A maltose-binding protein/annexin V chimera was synthesized and purified with high yield using amylose resin. We showed that it bound to phosphatidylserine in the ELISA as well as to that exposed on apoptotic Jurkat cells; therefore, it was used in the development of a method for radiolabeling annexin V using iodine radionuclides. MBP-annexin V retained its phosphatidylserine binding properties on direct iodination, but at high levels of oxidizing agents (iodogen and chloramine T), its specificity for phosphatidylserine was compromised. (124)I-MBP-annexin V was successfully used to image Fas-mediated hepatic cell death in BDF-1 mice using PET. In conclusion, we have shown that MBP-annexin V and the phosphatidylserine ELISA are useful tools for the development of methods for radiolabeling annexin V for PET imaging.

In vivo bioluminescence imaging of locally disseminated colon carcinoma in rats

Animal tumour models using orthotopic tumours for the evaluation of cancer therapies are of greater clinical relevance than subcutaneous models, but they also pose greater difficulties for measuring tumour size and quantifying response to treatment. In this study, we used noninvasive bioluminescence imaging to monitor the intraperitoneal growth of luciferase-transfected CC531 colorectal cells in adult WAG/RIJ rats. The bioluminescence signal correlated well with post-mortem assessment of tumour load by visual inspection of the peritoneal cavity at specific follow-up times. Using bioluminescence imaging, we were able to monitor peritoneal tumour growth sequentially in time and to calculate a tumour growth rate for each animal; this is not possible with invasive methods of evaluating tumour load. Bioluminescence imaging of rats treated with a single dose of cisplatin (4 mg kg⁻¹, i.p.) demonstrated a significant delay in peritoneal tumour growth relative to saline controls (mean 45.0±s.d. 13.0 vs 28.2±10.3 days; P=0.04). Similar protocols evaluated by visual scoring of tumour load at 40 days after inoculation supported these findings, although no quantitative assessment of treatment-induced growth delay could be made by this method. This study shows that in vivo imaging of luciferase-transfected tumour cells is a useful tool to investigate the dynamics of disseminated tumour growth and efficacy of anticancer treatment in orthotopic models of peritoneal cancer in rats. It offers an attractive alternative to invasive methods, and requires fewer animals for measuring tumour response to therapy.

Selective deficits in appetitive conditioning as a consequence of ethanol withdrawal

The acquisition of a conditioned response to a cue associated with a fearful event has been shown to be impaired in animals that had been repeatedly withdrawn from ethanol, but not in animals with the same chronic ethanol treatment but only a single withdrawal episode [D. N. Stephens et al. (2001) Eur. J. Neurosci., 14, 2023-2031]. Lesion studies have shown that the amygdala plays a vital role in this type of conditioning process. Here we investigate aspects of conditioning for appetitive reinforcers in operant tasks, also shown to rely on amygdala processing, in rats following repeated withdrawal from ethanol. Rats were chronically treated with either an ethanol-containing liquid diet for 24 days continuously (single withdrawal) or interspersed with 2 x 3-day withdrawal periods (repeated withdrawal), or with a control diet (control). Two weeks after the final withdrawal, operant training began. In tasks that are impaired by lesions of the basolateral amygdala, conditioned reinforcement and reinforcer devaluation, there was no effect of chronic ethanol treatment or withdrawal on acquisition or performance. However, in a task that is dependent upon functioning of the central nucleus of the amygdala, Pavlovian-to-instrumental transfer, the single and repeated withdrawal groups were significantly impaired. Therefore, chronic ethanol treatment and withdrawal resulted in deficits in behavioural tasks that are sensitive to central but not to basolateral amygdala lesions, and may reflect different sensitivities of these areas to ethanol.

Postpartum fetal head circumference and its influence on labour duration in nullipara

A retrospective analysis of postpartum fetal head circumference (FHC) and birth weight and its effect on the duration of labour was undertaken. The aim was to assess the predictive value of postpartum FHC versus birth weight in predicting dystocia. A FHC > 37 cm was associated significantly with a prolonged first and second stage of labour. A receiver operator curve (ROC) shows that the sensitivity and specificity of a FHC > 37 cm is as good as a fetal weight > 4.5 kg in predicting dystocia.

Cutting edge: bacterial flagellin activates basolaterally expressed TLR5 to induce epithelial proinflammatory gene expression

Flagellin, the structural component of bacterial flagella, is secreted by pathogenic and commensal bacteria. Flagellin activates proinflammatory gene expression in intestinal epithelia. However, only flagellin that contacts basolateral epithelial surfaces is proinflammatory; apical flagellin has no effect. Pathogenic Salmonella, but not commensal Escherichia coli, translocate flagellin across epithelia, thus activating epithelial proinflammatory gene expression. Investigating how epithelia detect flagellin revealed that cell surface expression of Toll-like receptor 5 (TLR5) conferred NF-kappaB gene expression in response to flagellin. The response depended on both extracellular leucine-rich repeats and intracellular Toll/IL-1R homology region of TLR5 as well as the adaptor protein MyD88. Furthermore, immunolocalization and cell surface-selective biotinylation revealed that TLR5 is expressed exclusively on the basolateral surface of intestinal epithelia, thus providing a molecular basis for the polarity of this innate immune response. Thus, detection of flagellin by basolateral TLR5 mediates epithelial-driven inflammatory responses to Salmonella.

Temporal clustering of hemorrhages from untreated cavernous malformations of the central nervous system

OBJECTIVE

Hemorrhages from cerebral cavernous malformations (CMs) sometimes seem to occur in closely spaced "clusters" interspersed with long hemorrhage-free intervals. Clustering of hemorrhages could affect retrospective assessments of radiosurgery efficacy in prevention of CM rehemorrhage. However, this empirical observation had not been tested quantitatively. To test whether CM hemorrhages tend to cluster, we reviewed pretreatment rebleeding rates after a first symptomatic hemorrhage in CM patients who later underwent surgery or radiosurgery.

METHODS

We performed a retrospective review of 141 patients with CMs who presented with clinically overt hemorrhage, and who subsequently underwent surgery or proton beam radiosurgery during an 18-year period. Statistical models were used to analyze all events per person and identify potential variation in rebleeding risk with time after a previous hemorrhage.

RESULTS

Sixty-three of 141 patients experienced a second hemorrhage before treatment; 16 had additional hemorrhages. Five hundred thirty-eight patient years elapsed between first hemorrhages and treatment. The cumulative incidence of a second hemorrhage after the first CM hemorrhage was 14% after 1 year and 56% after 5 years. During the first 2.5 years after a hemorrhage, the monthly rehemorrhage hazard was 2%. The risk then decreased spontaneously to less than 1% per month, which represents a 2.4-fold decline (P < 0.001). Rehemorrhage rates were higher in younger patients (P < 0.01), but not in females or in patients with deep lesions. Shorter intervals between successive hemorrhages did not predict higher subsequent rehemorrhage risk.

CONCLUSION

The rehemorrhage rate from untreated CMs is high initially, and it decreases 2 to 3 years after a previous hemorrhage. This hazard pattern generates the observed temporal clustering of hemorrhages from untreated CMs.

Benign meningioma: partially resected, biopsied, and recurrent intracranial tumors treated with combined proton and photon radiotherapy

PURPOSE/OBJECTIVE

To evaluate the recurrence-free survival and complications of combined proton and photon radiotherapy of patients with incompletely resected or recurrent histologically-confirmed benign meningioma.

METHODS AND MATERIALS

Between May 1981 and November 1996, 46 patients with partially resected, biopsied, or recurrent meningiomas (median age of 50 years; range 11-74 years) were treated with combined photon and 160-MeV proton beam therapy at the Massachusetts General Hospital (MGH) and the Harvard Cyclotron Laboratory, using computed tomography-based conformal 3D treatment planning. Nine patients were treated after incomplete tumor resection, 8 patients after tumor biopsy only, and 29 patients after tumor recurrence following gross total (10/29 patients) or progression after subtotal (19/29 patients) resection. All patients were classified as benign meningioma on review slides at MGH. The median dose to the macroscopic gross tumor volume was 59.0 CGE (range 53.1-74.1 CGE, CGE = proton Gy x 1.1 RBE). The median follow-up was 53 months (range 12-207).

RESULTS

Overall survival at 5 and 10 years was 93 and 77%, respectively, and the recurrence-free rate at 5 and 10 years was 100% and 88%, respectively. Survival without severe toxicity was 80% at 5 and 10 years. Three patients presented with local tumor recurrence at 61, 95, and 125 months. One patient developed distant intradural metastasis at 21 and 88 months. No patient died from recurrent meningioma; however, 4 patients died of other causes. A fifth patient died from a brainstem necrosis after 22 months. Eight patients developed severe long-term toxicity from radiotherapy, including ophthalmologic (4 patients), neurologic (4 patients), and otologic (2 patients) complications. All patients with ophthalmologic toxicity received doses higher than those allowed for the optic nerve structures in the current protocol.

CONCLUSION

Combined proton and photon radiotherapy is an effective treatment for patients with recurrent or incompletely resected benign intracranial menigiomas. Observed toxicity appears to be dose-related; with currently employed dose constraints, toxicity should not exceed that seen in patients treated with conformal fractionated supervoltage photon radiotherapy.