Systemic mastocytosis and probable mast cell leukaemia in a koala (Phascolarctos cinereus).

BACKGROUND: To the authors' knowledge, this is the first report of mast cell neoplasia in a koala (Phascolarctos cinereus). CASE REPORT: An adult female koala was presented for rapidly deteriorating health and death of a pouch young. Significant weight loss was apparent despite supplemental feeding; the abdomen was distended; and the koala was weak and mentally depressed. Haematology revealed a significant mastocytosis with a concurrent population of atypical mononuclear cells. The koala was euthanised and tissues were collected for histology. Bone marrow, lymph node, lung, stomach and spleen exhibited significant infiltration by mast cells. Atypical round cells consistent with those identified in the peripheral blood were also identified in the marrow. A diagnosis of systemic mastocytosis and probable mast cell leukaemia was made. Immunocytochemical and immunohistochemical staining was not able to further characterise the atypical cell population, and the mast cells exhibited only weak staining with CD117. CONCLUSION: The histological diagnosis, in this case, was systemic mastocytosis and myeloproliferative disease of uncertain origin. There was a dominant population of mast cells in the peripheral blood and marrow, and a population of circulating atypical mononuclear cells, appearing similar to mast cell leukaemia-acute myeloid leukaemia in humans.

Baseline morphometric, haematological and plasma biochemical parameters in free-ranging eastern water dragons (Intellagama lesueurii lesueurii).

OBJECTIVE: The aim of this study was to determine baseline reference data for morphometric measurements and haematological and plasma biochemical parameters in clinically healthy eastern water dragons (Intellagama lesueurii lesueurii), accounting for the variables of season and sex. The clinical objective was to provide clinicians and researchers with baseline reference intervals (RIs) in order to assess accurately the health of a population or individual animals. METHODS: The study group comprised 39 free-ranging eastern water dragons. To monitor seasonal changes in data two study periods were assigned: September-October 2009 (spring) and January-March 2010 (summer). The 18 males and 21 females were captured in the grounds of Taronga Zoo, Mosman (33°50'45'' S, 151°15'20'' E) in Sydney, New South Wales, Australia. Basic morphometric, haematological and plasma biochemical parameters were measured. RIs were generated in accordance with the American Society of Veterinary Clinical Pathology guidelines. Data were analysed for the effects of sex, season and sex-season interactions using restricted maximal likelihood modelling. RESULTS: Reference values were established in eastern water dragons for morphometric data and RIs were generated for haematological and plasma biochemical levels. The study showed seasonal variation in uric acid. Weight, total length, snout-vent length and basophil % showed significant differences according to sex. Sex-season interactions were detected for calcium, monocyte % and total protein (refractometry). CONCLUSION: Multiple parameters exhibited normal physiological variation between season and sex and an interaction between the two factors. These variables need to be considered in the clinical context when interpreting results of haematological and biochemical analyses in eastern water dragons. The RIs established from this population will provide a basis for further studies in both free-living and captive eastern water dragons, and for comparison in clinical cases.

Sex identification in the eastern blue-tongued lizard (Tiliqua scincoides White, ex Shaw, 1790) using morphometrics.

OBJECTIVE: To establish a repeatable, well-tolerated, non-invasive technique for sex identification in eastern blue-tongued lizards (Tiliqua scincoides). METHODS: Measurements were obtained from 69 free living eastern blue-tongued lizards presented for treatment that were either deceased on arrival or subsequently euthanased on welfare grounds. Weight, head width (H), snout vent length (SVL) and trunk length (T) were recorded. Ratios for head width to snout vent length (H/SVL%) and head width to trunk length (H/T%) were calculated. Sex was identified at necropsy. RESULTS: Evidence of sexual dimorphism in this population was shown. However, the degree of difference was subtle, requiring the use of ratios in order to refine the technique. Ratios of H/SVL% and H/T% showed significant predictability with respect to sex identification in both adult and sub-adult lizards. CONCLUSION: This study established a protocol for a repeatable, non-invasive technique for sex identification in the eastern blue-tongued lizard (Tiliqua scincoides) and provides a normal reference range.

The influence of interview on decision making and selection of prospective veterinary undergraduate students.

Interviews form part of the selection process in many veterinary programmes worldwide. This study aimed to evaluate the influence of the interview on veterinary selection decisions. An admissions cycle of interviews of 181 shortlisted school-leaving applicants to veterinary medicine was investigated. Selection panel pairs (from cohorts of 5 chairs and 11 cointerviewers) independently evaluated applicants before interview on the basis of their written application. Applicants were then interviewed and selectors repeated their evaluations, both independently and after joint discussion. Results of the preinterview and postinterview evaluations of the applicants were analysed statistically. There was slight to moderate agreement between the chair and cointerviewer on selection decisions/rankings taken before interview, but substantial agreement after interview. Agreement between postinterview decisions/rankings and consensus decisions/rankings postinterview was extremely high. Applicant attributes that had the most influence on selection decisions were: 'communication skills', 'overall knowledge gained from work experience' and 'ability to think on their feet'. There was significantly more agreement possible between interviewers with regard to selection decisions based on interview assessment compared with preinterview assessment of written applications. This study suggests that interviews may be a useful and important aid in decision making for selecting the candidates perceived as most suitable for this veterinary programme.

The anti-biofilm activity of lemongrass (Cymbopogon flexuosus) and grapefruit (Citrus paradisi) essential oils against five strains of Staphylococcus aureus.

AIMS: To determine the sensitivity of five strains of Staphylococcus aureus to five essential oils (EOs) and to investigate the anti-biofilm activity of lemongrass and grapefruit EOs. METHODS AND RESULTS: Antimicrobial susceptibility screening was carried out using the disk diffusion method. All of the strains tested were susceptible to lemongrass, grapefruit, bergamot and lime EOs with zones of inhibition varying from 2·85 to 8·60 cm although they were resistant to lemon EO. Lemongrass EO inhibited biofilm formation at 0·125% (v/v) as measured by colorimetric assay and at 0·25% (v/v) no metabolic activity was observed as determined by 2,3-bis(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide (XTT) reduction. Grapefruit EO did not show any anti-biofilm activity. Following exposure to lemongrass EO extensive disruption to Staph. aureus biofilms was shown under scanning electron microscopy. CONCLUSIONS: In comparison to the other EOs tested, lemongrass exhibited the most effective antimicrobial and anti-biofilm activity. SIGNIFICANCE AND IMPACT OF THE STUDY: The effect of lemongrass EO highlights its potential against antibiotic resistant Staph. aureus in the healthcare environment.

Evaluating the link between the management of clinical waste in the National Health Service (NHS) and the risk of the spread of infections: A case study of three hospitals in England.

This study aimed to evaluate waste management practices in three case study NHS Trusts in England and the potential risks of the spread of pathogens causing healthcare associated infections (HCAIs). Using a combination of microbiological techniques, interviews and questionnaire surveys, four target microbes were studied, namely: meticillin resistant Staphylococcus aureus (MRSA), meticillin sensitive Staphylococcus aureus (MSSA), Clostridium difficile (C. difficile) and vancomycin-resistant enterococci (VRE). Waste Flow Diagrams (WFDs) were used to map the flow of the waste. While there was a perceived link between the management of the waste and the spread of the microbes by staff, none of the target organisms were isolated. The findings suggest that when the waste is properly contained and managed that it should not pose a significant risk in terms of the spread of the four bacteria tested in this study. In addition, the results demonstrate that there is a need for staff perceptions and beliefs to be addressed in the development of policies and training related to infection control and its link to waste management.

Haptic devices as a paradigm to enhance learning/function--theory and empirical studies.

Haptics is a modern term employed to describe both afferent and efferent flows of forces with humans. The appropriate design of these force flow fields when coordinated with information to and from computers and other devices to physically challenged individuals can empower the performance of certain tasks previously not attainable. Extensive empirical work presented herein has demonstrated that proper augmentation of particular dynamic force fields, synchronised with certain cognitive tasks, can lead to improved functionality. More specifically, studies in spasticity, weaken responses and having delayed human response can benefit from these exposures to force fields applied suitably. From a theoretical perspective, the use of the well-known Fitts' law provides a unifying framework from which one can quantify the benefits derived from the proper exposure to force fields. Another area where haptics offers an exciting new platform to transfer information to and from humans includes subliminal haptics. This provides a paradigm to improve situational awareness and enhances control capability, where it may be missing previously. This article updates how haptics can be used in a variety of empirical settings to enhance learning, modulate human response to assist task completion, present a theoretical framework and improve the self-esteem of physically challenged individuals.

Characterisation of a pneumatic muscle test station with two dynamic plants in cascade.

Pneumatic muscle actuators (PMAs) offer significant advantages over more traditional actuators, which make them prime candidates in rehabilitation devices. A dynamic test station (DTS) is modified to demonstrate the use of a PMA for this application. The DTS includes two dynamic systems: a PMA and a DC servomotor. An overall transfer function was developed utilising characterisation data for the PMA and DC servomotor. A Tustin (bilinear) transform was performed on the overall transfer function to obtain a discrete time system. Model parameters were optimised and used to generate input voltage profiles that achieve isokinetic (constant velocity) task specifications. Percent root mean square error values (PRMSE) between the actual and ideal profiles were used to evaluate the accuracy of this method in achieving isokinetic displacement. For PMA pressures (in kPa) of 150, 350 and 550 PRMSE were 7.80, 5.40 and 2.76, respectively.

Characterisation of a phenomenological model for commercial pneumatic muscle actuators.

This study focuses on the parameter characterisation of a three-element phenomenological model for commercially available pneumatic muscle actuators (PMAs). This model consists of a spring, damping and contractile element arranged in parallel. Data collected from static loading, contraction and relaxation experiments were fitted to theoretical solutions of the governing equation for the three-element model resulting in prediction profiles for the spring, damping and contractile force coefficient. For the spring coefficient, K N/mm, the following relationships were found: K = 32.7 - 0.0321P for 150 < or = P < or = 314 kPa and K = 17 + 0.0179P for 314 < or = P < or = 550 kPa. For the damping coefficient, B Ns/mm, the following relationship was found during contraction: B = 2.90 for 150 < or = P < or = 550 kPa. During relaxation, B = 1.57 for 150 < or = P < or = 372 kPa and B = 0.311 + 0.00338P for 372 < or = P < or = 550. The following relationship for the contractile force coefficient, F(ce) N, was also determined: F(ce) = 2.91P+44.6 for 150 < or = P < or = 550 kPa. The model was then validated by reasonably predicting the response of the PMA to a triangular wave input in pressure under a constant load on a dynamic test station.

Tissue level mechanical properties of cortical bone in skeletally immature and mature dogs.

OBJECTIVES: The purpose of this study was to quantify the tissue level mechanical properties of cortical bone of skeletally immature (~five-month-old) Beagle dogs and compare them to data from mature dogs measured in a previous study. METHODS: Eight femoral cross sectional specimens (two bone sections / dog) were obtained from four skeletally immature dogs. A pair of calcein bone labels were administered intravenously to the dogs to mark sites of active mineralization prior to euthanasia. Prepared bone specimens were placed in a nano- indenter specimen holder and the previously identified calcein labelled osteons were located. Labelled (n = 128) and neighbouring unlabelled (n = 127) osteons in skeletally immature femurs were examined by instrumented indentation testing. Indents were made to a depth of 500 nm at a loading rate of 10 nm/s. Indentation modulus (IM) and hardness (H) were obtained. RESULTS: The overall IM of the cortical bone in the skeletally mature groups was significantly greater than in the immature group (p = 0.0011), however overall H was not significantly different. The differences between the groups in IM were significant for the unlabelled osteons (p = 0.001), but not for the labelled osteons (p = 0.56). CONCLUSION: There are differences in the IM of unlabelled osteons in skeletally immature and mature groups of Beagle dogs. In contrast to whole bone mechanical tests, where there are obvious differences between growing and mature bones, there are only small differences in the micro-mechanical properties.

Generation of MUC1-stimulated mononuclear cells using optimized conditions.

Mucin is a glycoprotein found on the surface of cell membranes of adenocarcinomas. The purpose of these studies was to generate MUC1 multiple tandem repeat (VNTR)-stimulated mononuclear cells (M1SMC). We first determined the optimal conditions to influence the immune response. In these studies, peripheral blood mononuclear cells (PBMC), from patients with adenocarcinomas, were stimulated by different numbers of M1SMC stimulations, various concentrations of MUC1 peptide, washing of PBMC prior to stimulation and days in culture, to determine the optimal conditions to influence the immune response. The results of this study indicate that the mononuclear cells (MC) stimulated twice 1 week apart with MUC1 VNTR1 produced a greater specific killing of the breast cancer cell line MCF-7 than the 0, 1, 3 or 4 weekly stimulations. The optimal molarity for inducing cytotoxicity and cytokines (granulocyte macrophage colony-stimulating factor, gamma-interferon and interleukin-10) was 45 x 10(-8) M (1 microg/ml); except for tumour necrosis factor (TNF)-alpha which was 22 x 10(-8) M (0.5 microg/ml). The unwashed MC were superior to washing them with Ficoll-Hypaque. The optimal number of days in culture for cytotoxicity and cytokine production was after two stimulations (i.e. after day 7). Optimum conditions for generation of M1SMC identified in these studies were two stimulations with peptide, concentration of 45 x 10(-8) M (1 microg/ml) peptide, unwashed cells, and after two stimulations or after 8 days in culture. M1SMC were generated from multiple patients with breast cancer which lysed adenocarcinoma cells.

The survival of three strains of Arcobacter butzleri in the presence of lemon, orange and bergamot essential oils and their components in vitro and on food.

AIMS: To test the effect of oils and vapours of lemon, sweet orange and bergamot and their components against three Arcobacter butzleri strains. METHODS AND RESULTS: The disc diffusion method was used to screen the oils and vapours against three strains of A. butzleri. In vitro bergamot was the most inhibitory essential oil (EO) and both citral and linalool were effective. On cabbage leaf, the water isolate was the least susceptible to bergamot EO, citral and linalool (1-2 log reduction), with the chicken isolate being the most susceptible (6-8 log reduction). However, the latter appeared not to be susceptible to vapours over 24 h although type strain and water isolate populations reduced by 8 logs. On chicken skin, the effectiveness of the oils was reduced compared with that on cabbage leaf. CONCLUSIONS: Bergamot was the most effective of the oils tested and linalool the most effective component. All strains tested were less susceptible in food systems than in vitro. SIGNIFICANCE AND IMPACT OF THE STUDY: Arcobacter isolates vary in their response to EO suggesting that the results of type strain studies should be interpreted with caution. Bergamot EO has the potential for the inhibition of this 'emerging' pathogen.

Context of MUC1 epitope: immunogenicity.

MUC1 is a glycoprotein found at the secretory poles of normal cells but is hypoglycosylated on the entire surface of cell membranes of adenocarcinomas. In order to determine the influence on the immune response of peptide context for epitope presentation, peripheral blood mononuclear cells (PBMC) from patients with adenocarcinomas, were stimulated with MUC1 peptides derived from the 20 amino acids (aa) long sequence that is characteristic of the MUC1 Variable Number of Tandem Repeats (VNTR). In the seven peptides tested, the T-cell tumor-specific epitope (cTSE) was surrounded by variable numbers of aa and repeated up to 5 times in the same peptide. The results of this study indicate that cultures stimulated with peptide 610 (GSTAPPAHGVTS APDTRPAP) showed the highest specific killing of the MUC1-expressing breast cancer MCF-7 cells. Peptide 610 is also superior to the other peptides in inducing better production of the type 1 cytokines, tissue necrosis factor alpha and interferon gamma. In conclusion, context of the epitope and not sequence alone determines immunogenicity.

The effect of lemon, orange and bergamot essential oils and their components on the survival of Campylobacter jejuni, Escherichia coli O157, Listeria monocytogenes, Bacillus cereus and Staphylococcus aureus in vitro and in food systems.

AIMS: To investigate the effectiveness of oils and vapours of lemon (Citrus limon), sweet orange (Citrus sinensis) and bergamot (Citrus bergamia) and their components against a number of common foodborne pathogens. METHODS AND RESULTS: The disc diffusion method was used to screen the oils and vapours against Listeria monocytogenes, Staphylococcus aureus, Bacillus cereus, Escherichia coli O157 and Campylobacter jejuni. The survival of each species, demonstrated to be susceptible in the in vitro studies, was tested on cabbage leaf for 60 s by direct contact and on chicken skin for 10 min by direct contact and 24 h by vapour. The results indicate that bergamot was the most inhibitory essential oil (EO) and citral and linalool mimicked its effect (P > 0.001). Citral and linalool vapours produced 6 log reductions in L. monocytogenes, Staph. aureus and B. cereus populations on cabbage leaf after 8-10 h exposure but bergamot vapour exposure, while producing a similar reduction in L. monocytogenes and B. cereus populations, had no effect on Staph. aureus. CONCLUSIONS: Bergamot was the most effective of the oils tested and linalool the most effective anti-bacterial component. Gram-positive bacteria were more susceptible than Gram-negative bacteria in vitro, although Camp. jejuni and E. coli O157 were inhibited by bergamot and linalool oils and by linalool vapour. All bacteria tested were less susceptible in food systems than in vitro. Of the Gram-positive bacteria tested Staph. aureus was the least susceptible to both the oils and the components tested. SIGNIFICANCE AND IMPACT OF THE STUDY: Results suggest the possibility that citrus EOs, particularly bergamot, could be used as a way of combating the growth of common causes of food poisoning.

Communication education in veterinary in the United Kingdom and Ireland: the NUVACS project coupled to progressive individual school endeavors.

This article reports on the coordination of communications skills training in veterinary schools in the United Kingdom and Ireland and describes the progress and status of training that is occurring in six of these schools.

Biomimetic model of skeletal muscle isometric contraction: I. an energetic-viscoelastic model for the skeletal muscle isometric force twitch.

This paper describes a revision of the Hill-type muscle model so that it will describe the chemo-mechanical energy conversion process (energetic) and the internal-element stiffness variation (viscoelastic) during a skeletal muscle isometric force twitch contraction. The derivation of this energetic-viscoelastic model is described by a first-order linear ordinary differential equation with constant energetic and viscoelastic coefficients. The model has been implemented as part of a biomimetic model, which describes the excitation-contraction coupling necessary to drive the energetic-viscoelastic model. Finally, the energetic-viscoelastic model is validated by comparing its isometric force-time profile with that of various muscles reported in the literature.

Biomimetic model of skeletal muscle isometric contraction: II. A phenomenological model of the skeletal muscle excitation-contraction coupling process.

This paper describes a new macroscopic, phenomenological model of the skeletal muscle excitation-contraction coupling process, as represented by four principal and consecutive compartments (biophysical, biochemical, and biomechanical phases) characteristic of isometric excitation-contraction coupling in mammalian skeletal muscle, and coupled by a system of simultaneous, first-order linear ordinary differential equations. The model is based upon biological compartmental transport kinetics and irreversible thermodynamic energy transformation, and represents a distinct improvement over other biomimetic models. The model was derived using physiological parameter data published in the literature, and validated using MATLAB R12.

Modeling the dynamic characteristics of pneumatic muscle.

A pneumatic muscle (PM) system was studied to determine whether a three-element model could describe its dynamics. As far as the authors are aware, this model has not been used to describe the dynamics of PM. A new phenomenological model consists of a contractile (force-generating) element, spring element, and damping element in parallel. The PM system was investigated using an apparatus that allowed precise and accurate actuation pressure (P) control by a linear servo-valve. Length change of the PM was measured by a linear potentiometer. Spring and damping element functions of P were determined by a static perturbation method at several constant P values. These results indicate that at constant P, PM behaves as a spring and damper in parallel. The contractile element function of P was determined by the response to a step input in P, using values of spring and damping elements from the perturbation study. The study showed that the resulting coefficient functions of the three-element model describe the dynamic response to the step input of P accurately, indicating that the static perturbation results can be applied to the dynamic case. This model is further validated by accurately predicting the contraction response to a triangular P waveform. All three elements have pressure-dependent coefficients for pressure P in the range 207 < or = P < or = 621 kPa (30 < or = P < or = 90 psi). Studies with a step decrease in P (relaxation of the PM) indicate that the damping element coefficient is smaller during relaxation than contraction.

Role for c-jun N-terminal kinase in treatment-refractory acute myeloid leukemia (AML): signaling to multidrug-efflux and hyperproliferation.

A relationship was proved between constitutive activity of leukemic cell c-jun-N-terminal kinase (JNK) and treatment failure in AML. Specifically, early treatment failure was predicted by the presence of constitutive JNK activity. The mechanistic origins of this association was sought. A multidrug resistant leukemic cell line, HL-60/ADR, characterized by hyperexpression of c-jun and JNK activity, was transfected with a mutant c-jun vector, whose substrate N-terminal c-jun serines were mutated. Down-regulated expression occurred of c-jun/AP-1-dependent genes, catalase and glutathione-S-transferase (GST) pi, which participate in cellular homeostasis to oxidative stress and xenobiotic exposure. MRP-efflux was abrogated in HL-60/ADR cells with dominant-negative c-jun, perhaps because MRP1 protein expression was also lost. Heightened sensitivity to daunorubicin resulted in cells subjected to this change. Biochemical analysis in 67 primary adult AML samples established a statistical correlation between cellular expression of c-jun and JNK activity, JNK activity with hyperleukocytosis at presentation of disease, and with exuberant MRP efflux. These findings reflect the survival role for c-jun/AP-1 and its regulatory kinase previously demonstrated for yeast in homeostatic response to oxidative stress and in operation of ATP-binding cassette efflux pumps, and may support evolutionary conservation of such function. Thus, JNK and c-jun may be salient drug targets in multidrug resistant AML.

In vitro activity of Melaleuca alternifolia (tea tree) oil against bacterial and Candida spp. isolates from clinical specimens.

This study investigates the in vitro activity of tea tree oil (TTO) against a range of wild strains of microorganisms isolated from clinical specimens of leg ulcers and pressure sores. The antimicrobial effectiveness of TTO is determined in terms of minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) or minimum fungicidal concentration (MFC). The isolates include methicillin-resistant Staphylococcus aureus (MRSA), S. aureus, faecal streptococci, beta-haemolytic streptococci, coagulase-negative staphylococci, Pseudomonas spp. and coliform bacilli. Eleven Candida spp. isolates from skin and vaginal swabs also are tested. Using an agar dilution assay, the MICs of TTO in 88 out of 90 isolates was 0.5-1.0% (v/v), whilst with P. aeruginosa it was >2% (v/v). A broth microdilution method was used to determine MIC and minimum cidal concentration (MCC) of 80 isolates. In 64 isolates, TTO produced an inhibitory and cidal effect at 3% and 4% (v/v), respectively. S. aureus and Candida spp. were the most susceptible to TTO, with MICs and MBCs of 0.5% and 1%, respectively. P. aeruginosa and the faecal streptococci isolates, with MICs and MBCs of >8%, were resistant to TTO.