Acute phase protein levels in dogs with mast cell tumours and sarcomas

<p><b>Context:</b> The acute phase protein response is part of a non-specific and complex host response to inflammation. It occurs shortly after tissue injury and may be induced by a range of different causes, including infectious, inflammatory, neoplastic, traumatic or immunological disease. Although it was conventionally believed that APPs were exclusively hepatocyte derived, there is increasing evidence to support extra-hepatic generation in neoplastic and other disease states. In people, C-reactive protein (CRP) has been shown to be of value in identifying metastatic disease from primary renal tumours as well as showing promise for monitoring rejection of renal transplants. Serum CRP correlates with survival in colorectal cancer and oesophageal squamous cell carcinoma while serum amyloid A (SAA) concentrations correlate with cancer activity, stage and prognosis in gastric tumours. Recent immunohistochemical studies in people with oesophageal carcinoma suggest that tumour tissue may itself elaborate APP with a poorer survival and outcome associated with tumours elaborating higher levels of CRP. A similar association has been seen between alpha-1 acid glycoprotein (AGP) and colorectal tumours and ovarian carcinoma.</p> <p>As yet, studies regarding APP values in neoplastic conditions in dogs are limited, and many are non-specific. In veterinary patients, elevated levels of AGP have been identified in dogs with a range of tumours with localisation to liver and splenic tissue in one study. Another study found higher levels of AGP in dogs with non-specific tumours of grade III-IV based on the WHO Tumour Node Metastasis (TNM) scale and elevated serum AGP has been documented in non-specific tumour-bearing cats. Elevated CRP levels have been documented in both dogs and cats with lymphoma and serum CRP may be used as an indicator of complete remission status in dogs with multicentric lymphoma. Elevated levels of CRP, Haptoglobin (Hp) and SAA have been identified in dogs with mammary tumours, with significant increases over normal in the presence of metastatic disease, primary tumours greater than 5cm in diameter and those with ulceration.</p> <p>In this study we evaluated an APP profile using four APPs (CRP, Hp, SAA and AGP), in dogs with mast cell tumours (MCTs) and sarcomas to assess whether the APP profile would change in reflection of tumour presence; whether the extent of any change would correlate with tumour grade; and whether the changes would differ with tumour type.</p> <p><b>Approach:</b> Patients with naturally occurring MCTs and sarcomas presenting for staging and treatment were included if they met the study criteria. Criteria for inclusion were that the patient was not currently being treated with steroids, did not have a recent history of infectious or inflammatory disease other than the tumour, a definitive histological diagnosis was available and a full staging procedure was completed prior to surgery using standard oncological protocols to identify metastatic disease where present. Following surgical resection each tumour was submitted for full histological evaluation and grading to include assessment of the margins of excision. Cases were only enrolled in the study if blood sampling formed part of the clinical investigation and/or treatment, and where residual blood was available after diagnostic sampling which would otherwise have been disposed of as clinical waste. In brief, the CRP levels were determined by immunoturbidometric assay and Hp by means of haemoglobin binding capacity assay. SAA was measured with a commercial canine ELISA kit (TriDelta Development, Dublin, Ireland) and AGP was measured with a commercial radial immunodiffusion assay (J-Path Inc, Tokyo, Japan).</p> <p><b>Results:</b> All comparisons using continuous data were checked for normality and equality of variances and appropriate statistical tests were employed (student’s t test operationalised as a two-sample Welch’s test for samples of unequal sizes and variances, Mann-Whitney, Chi-square and Fishers exact tests as appropriate). In MCTs, the CRP and AGP were elevated above reference ranges, Hp showed no significant change and SAA dropped relative to the reference range. In sarcoma patients CRP, Hp and AGP were all elevated above reference ranges. None of the tumour grade differences were significant apart from SAA in sarcoma patients where values in grade 2 sarcoma were significantly higher than those in grade 1.</p> <p><b>Interpretation and notes of caution:</b> The numbers in our groups were small which compromises the validity of statistical evaluation so our results must be interpreted with caution. However some interesting relationships have emerged from the initial evaluation which suggests that APP profiles may have potential for screening in patients with neoplastic disease. For patients with MCTs, CRP and AGP levels would be expected to increase, with a concurrent drop in SAA levels. In sarcoma patients CRP, AGP and Hp can all be expected to increase. These initial results need to be evaluated in larger numbers of cases with naturally occurring disease to validate the findings, to assess whether the presence and extent of metastatic disease has a significant effect, and also to confirm whether the values alter after surgical resection of the primary tumour.</p> <p><b>Significance of findings:</b> If there are consistent and specific changes in APP profiles associated with different tumour types in dogs, as is the case with a wide range of cancers in humans, then there may be potential for APP profiles on routine blood samples to be used as indicators of disease, or where monitoring for recurrence. Whether they could also have potential for assessment of the presence of metastatic disease and prognosis as in people is unknown as yet.</p&gt

Groundwater reinjection and heat dissipation: lessons from the operation of a large groundwater cooling system in Central London

The performance of a large open-loop groundwater cooling scheme in a shallow alluvial aquifer at a prominent public building in Central London has been monitored closely over its first 2 years of operation. The installed system provided cooling to the site continuously for a period of 9 months between June 2012 and April 2013. During this period, c. 131300 m3 of groundwater was abstracted from a single pumping well and recharged into a single injection borehole. The amount of heat rejected in this period amounts to c. 1.37 GWh. A programme of hydraulic testing was subsequently undertaken over a 3 month period between July and October 2013 to evaluate the performance of the injection borehole. The data indicate no significant change in injection performance between commissioning trials undertaken in 2010 and the most recent period of testing, as evidenced by comparison of injection pressures for given flow rates in 2010 and 2013. Continuous temperature monitoring of the abstracted water, the discharge and a number of observation wells demonstrates the evolution of a heat plume in the aquifer in response to heat rejection and subsequent dissipation of this heat during the 18 month planned cessation

An investigation into the effect of thickness of titanium dioxide and gold-silver nanoparticle titanium dioxide composite thin-films on photocatalytic activity and photo-induced oxygen production in a sacrificial system

Thin films of titanium dioxide and titanium dioxide with incorporated gold and silver nanoparticles were deposited onto glass microscope slides, steel and titanium foil coupons by two sol–gel dip-coating methods. The film's photocatalytic activity and ability to evolve oxygen in a sacrificial solution were assessed. It was found that photocatalytic activity increased with film thickness (from 50 to 500 nm thick samples) for the photocatalytic degradation of methylene blue in solution and resazurin redox dye in an intelligent ink dye deposited on the surface. Contrastingly, an optimum film thickness of [similar]200 nm for both composite and pure films of titanium dioxide was found for water oxidation, using persulfate (S2O82−) as a sacrificial electron acceptor. The nanoparticle composite films showed significantly higher activity in oxygen evolution studies compared with plain TiO2 films

Effect of dislocations on charge carrier mobility-lifetime product in synthetic single crystal diamond

The authors report correlations between variations in charge transport of electrons and holes in synthetic single crystal diamond and the presence of nitrogen impurities and dislocations. The spatial distribution of these defects was imaged using their characteristic luminescence emission and compared with maps of carrier drift length measured by ion beam induced charge imaging. The images indicate a reduction of electron and hole mobility-lifetime product due to nitrogen impurities and dislocations. Very good charge transport is achieved in selected regions where the dislocation density is minimal

Pressure-Induced Insulating State in Ba1-xRExIrO3 (RE = Gd, Eu) Single Crystals

BaIrO3 is a novel insulator with coexistent weak ferromagnetism, charge and spin density wave. Dilute RE doping for Ba induces a metallic state, whereas application of modest pressure readily restores an insulating state characterized by a three-order-of-magnitude increase of resistivity. Since pressure generally increases orbital overlap and broadens energy bands, a pressure-induced insulating state is not commonplace. The profoundly dissimilar responses of the ground state to light doping and low hydrostatic pressures signal an unusual, delicate interplay between structural and electronic degrees of freedom in BaIrO3