Mycobacterium microti tuberculosis in its maintenance host, the field vole (Microtus agrestis): characterization of the disease and possible routes of transmission

The field vole (Microtus agrestis) is a known maintenance host of Mycobacterium microti. Previous studies have shown that infected animals develop tuberculosis. However, the disease is also known in cats and is sporadically reported from humans and other mammalian species. We examined trapped field voles from an endemic area, using a range of diagnostic approaches. These confirmed that a combination of gross and histological examination with culture is most appropriate to identify the true prevalence of the disease, which was shown to be more than 13% at times when older animals that have previously been shown to be more likely to develop the disease dominate the population. The thorough pathological examination of diseased animals showed that voles generally develop systemic disease with most frequent involvement of spleen and liver, followed by skin, lymph nodes, and lungs. The morphology of the lesions was consistent with active disease, and their distribution suggested skin wounds or oral and/or aerogenic infection as the main portal of entry. The demonstration of mycobacteria in open skin lesions, airways, and salivary glands indicated bacterial shedding from the skin and with sputum and saliva. This suggests not only the environment but also direct contact and devouring as likely sources of infection.

Interpenetration, deflection, and stagnation of cylindrically convergent magnetized supersonic tungsten plasma flows

The interpenetration and interaction of supersonic, magnetized tungsten plasma flows has been directly observed via spatially and temporally resolved measurements of the Thomson scattering ion feature. A novel scattering geometry allows independent measurements of the axial and radial velocity components of the ions. The plasma flows are produced via the pulsed power driven ablation of fine tungsten wires in a cylindrical wire array z pinch. Fits of the data reveal the variations in radial velocity, axial velocity, and temperature of the ion streams as they interpenetrate and interact. A previously unobserved increase in axial velocity is measured near the array axis. This may be the result of v[over →]×B[over →] bending of the ion streams by a toroidal magnetic field, advected to and accumulated about the axis by the streams.

A comparison study of haemolysis production in three contemporary centrifugal pumps

One challenge in providing extracorporeal circulation is to supply optimal flow while minimising adverse effects, such as haemolysis. To determine if the recent generation constrained vortex pumps with their inherent design improvements would lead to reduced red cell trauma, we undertook a study comparing three devices. Utilizing a simulated short-term ventricular assist circuit primed with whole human blood, we examined changes in plasma free haemoglobin values over a six-day period. The three pumps investigated were the Maquet Rotaflow, the Levitronix PediVAS and the Medos Deltastream DP3.This study demonstrated that all three pumps produced low levels of haemolysis and are suitable for use in a clinical environment. The Levitronix PediVAS was significantly less haemolytic than either the Rotaflow (p<0.05) or the DP3 (p<0.05). There was no significant difference in plasma free haemoglobin between the Rotaflow and the DP3 (p=0.71).

Abstract P2-09-03: Antitumor activity of the glutaminase inhibitor, CB-839, in triple-negative breast cancer

Glutamine (Gln) serves as an important source of energy and building blocks for many tumor cells. The first step in Gln utilization is its conversion to glutamate (Glu) by the mitochondrial enzyme glutaminase. CB-839 is a potent, selective, and orally bioavailable inhibitor of both splice variants of glutaminase (KGA and GAC). CB-839 inhibits recombinant GAC with an IC50 of &lt;15 nM. Treatment of the triple-negative breast cancer (TNBC) cell line MDA-MB-231 in vitro with CB-839 reduced cell viability and suppressed cellular Glu pools with comparable potency (IC50 ∼15 nM). TNBC breast cancer cell lines have been reported to have a heightened dependence on exogenous Gln for growth relative to estrogen receptor (ER) positive cells (Kung et al, 2011). Consistent with this observation, an analysis of 58 breast cancer cell lines in the Cancer Cell Line Encyclopedia revealed that low ER and/or Her2 expression is correlated with high glutaminase expression (particularly the GAC isoform) and low expression of glutamine synthetase (GLUL), an enzyme that converts Glu to Gln. This reciprocal pattern of GAC and GLUL expression suggests that TNBC may be particularly sensitive to glutaminase inhibition. To test this hypothesis, the anti-tumor activity of CB-839 was evaluated on a panel of breast tumor cell lines (n&gt;25) that included a mixture of TNBC and ER/Her2-positive subtypes. The TNBC subtype displayed the greatest sensitivity to CB-839 treatment (IC50s ranging from 5-100 nM) and this sensitivity was correlated with: i) dependence on extracellular Gln for growth (r = 0.83, p&lt;0.0001); ii) GAC (but not KGA) expression (r = -0.76, p&lt;0.0001); iii) glutaminase activity in cell lysates (r = -0.75, p = 0.0002); and iv) the ratio of cellular Glu to Gln (r = 0.53, p = 0.014) indicative of efficient Gln to Glu conversion. CB-839 also displayed significant anti-tumor activity in two TNBC xenograft models: 1) as a single agent in a patient-derived tumor chosen based on Gln utilization biomarkers and 2) in a cell line model (JIMT1) both as a single agent and in combination with paclitaxel. To determine if potential markers of Gln utilization and CB-839 sensitivity are reflected in primary tumors, an analysis of large mRNA expression and metabolomic datasets was undertaken. Consistent with the observations in cell lines, there was significantly elevated expression of GAC and reduced expression of GLUL in TNBC tumors relative to the ER+ population in The Cancer Genome Atlas mRNA expression dataset (n = 756). Likewise, analysis of the metabolite levels in 262 primary breast tumors showed that the Glu to Gln ratio in the ER- populations was significantly elevated relative to the ER+ population (fold increase = 3.2, p = 8.0E-09). This elevated metabolite ratio in the ER- population was also significantly correlated with the mRNA expression level of GLUL (r = -0.27, p = 0.001). These observations suggest that biomarkers of Gln utilization and CB-839 sensitivity extend to primary TNBC tumors. Together with the in vitro and in vivo preclinical anti-tumor activity of CB-839 in TNBC models, this primary tumor biomarker evaluation provides a strong rationale for the clinical investigation of CB-839 as a targeted therapeutic in TNBC patients.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P2-09-03.

Urinary biomarkers of kidney injury are associated with all-cause mortality in the Women's Interagency HIV Study (WIHS)

OBJECTIVES

Chronic kidney disease (CKD) is common in HIV-infected individuals, and is associated with mortality in both the HIV-infected and general populations. Urinary markers of tubular injury have been associated with future kidney disease risk, but associations with mortality are unknown.

METHODS

We evaluated the associations of urinary interleukin-18 (IL-18), liver fatty acid binding protein (L-FABP), kidney injury molecule-1 (KIM-1), neutrophil gelatinase-associated lipocalin (NGAL) and the albumin-to-creatinine ratio (ACR) with 10-year, all-cause death in 908 HIV-infected women. Serum cystatin C was used to estimate the glomerular filtration rate (eGFRcys).

RESULTS

There were 201 deaths during 9269 person-years of follow-up. After demographic adjustment, compared with the lowest tertile, the highest tertiles of IL-18 [hazard ratio (HR) 2.54; 95% confidence interval (CI) 1.75-3.68], KIM-1 (HR 2.04; 95% CI 1.44-2.89), NGAL (HR 1.50; 95% CI 1.05-2.14) and ACR (HR 1.63; 95% CI 1.13-2.36) were associated with higher mortality. After multivariable adjustment including adjustment for eGFRcys, only the highest tertiles of IL-18 (HR 1.88; 95% CI 1.29-2.74) and ACR (HR 1.46; 95% CI 1.01-2.12) remained independently associated with mortality. Findings for KIM-1 were borderline (HR 1.41; 95% CI 0.99-2.02). We found a J-shaped association between L-FABP and mortality. Compared with persons in the lowest tertile, the HR for the middle tertile of L-FABP was 0.67 (95% CI 0.46-0.98) after adjustment. Associations were stronger when IL-18, ACR and L-FABP were simultaneously included in models.

CONCLUSIONS

Among HIV-infected women, some urinary markers of tubular injury are associated with mortality risk, independently of eGFRcys and ACR. These markers represent potential tools with which to identify early kidney injury in persons with HIV infection.

From principles to practice: a spatial approach to systematic conservation planning in the deep sea

Increases in the demand and price for industrial metals, combined with advances in technological capabilities have now made deep-sea mining more feasible and economically viable. In order to balance economic interests with the conservation of abyssal plain ecosystems, it is becoming increasingly important to develop a systematic approach to spatial management and zoning of the deep sea. Here, we describe an expert-driven systematic conservation planning process applied to inform science-based recommendations to the International Seabed Authority for a system of deep-sea marine protected areas (MPAs) to safeguard biodiversity and ecosystem function in an abyssal Pacific region targeted for nodule mining (e.g. the Clarion-Clipperton fracture zone, CCZ). Our use of geospatial analysis and expert opinion in forming the recommendations allowed us to stratify the proposed network by biophysical gradients, maximize the number of biologically unique seamounts within each subregion, and minimize socioeconomic impacts. The resulting proposal for an MPA network (nine replicate 400 × 400 km MPAs) covers 24% (1 440 000 km(2)) of the total CCZ planning region and serves as example of swift and pre-emptive conservation planning across an unprecedented area in the deep sea. As pressure from resource extraction increases in the future, the scientific guiding principles outlined in this research can serve as a basis for collaborative international approaches to ocean management.

A pilot study to measure marks in children with cerebral palsy using a novel measurement template

AIM

The primary aim of this pilot study was to trial a method of assessing bruises in a population of disabled children. If the method was found to be sufficiently robust it would be our intention to undertaking a more extensive observational study.

BACKGROUND

Less is known about normal bruising patterns in children with disability than in those without. It is important that the method used to assess bruising is objective and repeatable. In an effort to define and improve repeatability, we employed a novel bruise measurement template which was printed onto transparent acetate sheets.

METHOD

Twenty primary school age children, the majority of whom were non-ambulant and severely disabled with cerebral palsy, underwent full skin examination. The template was used to assess any bruises seen. A comparison was then made between measurements made by experienced paediatricians using the template and using a standard tape measure on a series of bruise images in 25 photographs.

RESULTS

The majority of children in our pilot were found to have bruises, with one child having 6 and one 7 bruises. This comparative study showed that the two techniques had a very similar precision and that the template was easy to use. Greater precision would require a tighter measurement protocol, whether with a template or a tape measure.

CONCLUSIONS

Further evaluation of the application of such a template would be worthwhile. We would suggest that our finding of some bruising in this population of disabled children is borne in mind whenever bruising is found in a non-ambulant child.

Transitions to palliative care for older people in acute hospitals: a mixed-methods study

Background

Improving the provision of palliative and end-of-life care is a priority for the NHS. Ensuring an appropriately managed ‘transition’ to a palliative approach for care when patients are likely to be entering the last year of life is central to current policy. Acute hospitals represent a significant site of palliative care delivery and specific guidance has been published regarding the management of palliative care transitions within this setting.

Aims

(1) to explore how transitions to a palliative care approach are managed and experienced in acute hospitals and to identify best practice from the perspective of clinicians and service users; (2) to examine the extent of potentially avoidable hospital admissions amongst hospital inpatients with palliative care needs.

Design

A mixed-methods design was adopted in two hospitals in England, serving diverse patient populations. Methods included (1) two systematic reviews; (2) focus groups and interviews with 58 health-care professionals to explore barriers to, and facilitators of, palliative care transitions in hospital; (3) a hospital inpatient survey examining palliative care needs and aspects of management including a self-/proxy-completed questionnaire, a survey of medical and nursing staff and a case note review; (4) in-depth interviews with 15 patients with palliative care needs; (5) a retrospective case note review of all inpatients present in the hospital at the time of the survey who had died within the subsequent 12 months; and (6) focus groups with 83 key decision-makers to explore the implications of the findings for service delivery and policy.

Results

Of the 514 patients in the inpatient survey sample, just over one-third (n = 185, 36.0%) met one or more of the Gold Standards Framework (GSF) prognostic indicator criteria for palliative care needs. The most common GSF prognostic indicator was frailty, with almost one-third of patients (27%) meeting this criteria. Agreement between medical and nursing staff and the GSF with respect to identifying patients with palliative care needs was poor. In focus groups, health professionals reported difficulties in recognising that a patient had entered the last 12 months of life. In-depth interviews with patients found that many of those interviewed were unaware of their prognosis and showed little insight into what they could expect from the trajectory of their disease. The retrospective case note review found that 35 (7.2%) admissions were potentially avoidable. The potential annual cost saving across both hospitals of preventing these admissions was approximately £5.3M. However, a 2- or 3-day reduction in length of stay for these admissions would result in an annual cost saving of £21.6M or £32.4M respectively.

Conclusions

Patients with palliative care needs represent a significant proportion of the hospital inpatient population. There is a significant gap between NHS policy regarding palliative and end-of-life care management in acute hospitals in England and current practice.

Funding

The National Institute for Health Research Health Services and Delivery Research programme.