Clinical enzymology of the dog and cat.

Clinical enzymology studies the enzyme activity in serum or other body fluids for the diagnosis, prognosis or monitoring of a variety of diseases. Clinical enzymology has greatly benefited from advances in technology and is now an integral part of laboratory analysis. However, to maximise the clinical benefits of serum enzyme measurement, clinicians and clinical pathologists must have a good understanding of the pathophysiology behind serum enzyme alterations. They must also be aware of the preanalytical and analytical factors that can affect the accuracy of serum enzyme activity measurement. This review article first covers the basic concepts of clinical enzymology and the general mechanisms related to serum enzyme alterations. Then, the review discusses the potential effects of various preanalytical and analytical factors on enzyme activity measurement. Lastly, it explores the pathophysiology and clinical use of various serum enzymes in canine and feline medicine. The present review article aims to be a comprehensive one-stop source for clinical pathologists and small animal practitioners.

No effects of transcranial direct current stimulation on visual evoked potential and peak gamma frequency.

Evidence suggests that the visual evoked potential (VEP) and gamma oscillations elicited by visual stimuli reflect the balance of excitatory and inhibitory (E-I) cortical processes. As tDCS has been shown to modulate E-I balance, the current study investigated whether amplitudes of VEP components (N1 and P2) and peak gamma frequency are modulated by transcranial direct current stimulation (tDCS). Healthy adults underwent two electroencephalography (EEG) recordings while viewing stimuli designed to elicit a robust visual response. Between the two recordings, participants were randomly assigned to three tDCS conditions (anodal-, cathodal-, and sham-tDCS) or received no-tDCS. tDCS electrodes were placed over the occipital cortex (Oz) and the left cheek with an intensity of 2 mA for 10 min. Data of 39 participants were analysed for VEP amplitudes and peak gamma frequency using mixed-model ANOVAs. The results showed no main effects of tDCS in any metric. Possible explanations for the absence of tDCS effects are discussed.

Investigating the effects of tDCS on Visual Orientation Discrimination Task Performance: 'The possible influence of placebo'.

The non-invasive neuromodulation technique tDCS offers the promise of a low cost tool for both research and clinical applications in psychology, psychiatry and neuroscience. However, findings regarding its efficacy are often equivocal. A key issue is that the clinical and cognitive applications studied are often complex and thus effects of tDCS are difficult to predict given its known effects on the basic underlying neurophysiology, namely alterations in cortical inhibition-excitation balance. As such, it may be beneficial to assess the effects of tDCS in tasks whose performance has a clear link to cortical inhibition-excitation balance such as the visual orientation discrimination task (ODT). In prior studies in our laboratory no practise effects were found during 2 consecutive runs of the ODT, thus in the current investigation, to examine the effects of tDCS, subjects received 10 minutes of 2mA occipital tDCS (sham, anode, cathode) between a first and second run of ODT. Surprisingly, subjects' performance significantly improved in the second run of ODT compared to the first one regardless of the tDCS stimulation type they received (anodal, cathodal, or sham-tDCS). Possible causes for such an improvement could have been due to either a generic 'placebo' effect of tDCS (as all subjects received some form of tDCS) or an increased delay period between the two runs of ODT of the current study compared to our previous work (10 minutes duration required to administer tDCS as opposed to ~2 minutes in previous studies as a 'break'). As such, we tested these two possibilities with a subsequent experiment in which subjects received 2 minutes or 10 minutes delay between the 2 runs (with no tDCS) or 10 minutes of sham-tDCS. Only sham-tDCS resulted in improved performance thus these data add to a growing literature suggesting that tDCS has powerful placebo effect that may occur even in the absence of active cortical modulation.

Characterization of Black Pigmenturia in a Cat with Apocrine Gland Cystadenocarcinoma.

An 8-year-old neutered female domestic shorthair cat was presented for further management of an apocrine gland cystadenocarcinoma. Extensive nodal metastasis was diagnosed and the cat was humanely destroyed 2 months after presentation. Post-mortem histopathology of the cystadenocarcinoma revealed areas of yellow-brown granular pigmentation on light microscopy, staining positively for reducing substances with Schmorl's stain and demonstrating autofluorescence on confocal microscopy. The cat's urine was black and also exhibited autofluorescence, and further analysis revealed increased free pentosidine. Based on these findings, it was presumed that the apocrine gland cystadenocarcinoma was producing lipofuscin-like pigments and that the characteristics of the urine were at least partially secondary to advanced glycation end-products.

Investigation of the relationship between ionised and total calcium in dogs with ionised hypercalcaemia.

OBJECTIVES: To investigate the relationship between total and ionised calcium concentrations in dogs with ionised hypercalcaemia and to evaluate how albumin influences this relationship. METHODS: Initially, a reference interval for ionised and total calcium was established using a large population of healthy adult dogs. Our teaching hospital clinical database was searched to identify adult dogs with ionised hypercalcaemia between 2012 and 2017, a time frame when the same sample handling and analysis protocols were in place as for the healthy reference interval population. The relationship between ionised and total calcium concentrations was then examined in the ionised hypercalcaemia population. RESULTS: Based on biochemical analysis of 351 healthy adult dogs, a reference interval of 1.18 to 1.53 mmol/L for ionised calcium and 2.24 to 2.85 mmol/L for total calcium was established. Using these reference intervals, 63 dogs with ionised hypercalcaemia were identified, of which 23 did not have total hypercalcaemia. Only seven of the 23 dogs with ionised hypercalcaemia and total calcium below the upper limit of the reference interval had hypoalbuminemia. The majority of dogs with ionised hypercalcemia and normal total calcium had a modest increase in ionised calcium. CLINICAL SIGNIFICANCE: If relying on total calcium alone, more than one third of dogs with ionised hypercalcaemia will be classified as normocalcaemic and the majority of these dogs had normal serum albumin.

Mentorship Needs for Radiation Oncology Residents: Implications for Programme Design.

AIMS: Mentorship during residency guides and supports professional and personal development. Despite this, mentorship programmes within many postgraduate medicine programmes, including radiation oncology, are not standard. The objective of this qualitative study was to carry out a needs assessment to determine the perceived mentorship needs and experiences of radiation oncology residents and faculty. MATERIALS AND METHODS: Radiation oncology residents and faculty from a single university were invited to participate in semi-structured interviews in September 2017. Interviews were audiotaped and transcribed verbatim. An inductive thematic analysis was carried out using NVivo Pro version 11. Data collection occurred until saturation. Codes were derived and a systematic framework was applied to yield emergent themes. Trustworthiness was verified through triangulation and member checking. RESULTS: Twenty interviews (10 residents and 10 faculty) took place between October and December 2017, at which point thematic saturation was achieved. Four major themes emerged: (i) the perceived experiences of residents and faculty with mentorship, (ii) the evolution of mentorship needs during residency training, (iii) the mechanisms of creating mentorship relationships and (iv) peer mentorship. CONCLUSIONS: In this study, the perceptions of mentorship from the perspective of radiation oncology residents and faculty were explored. Important areas of alignment and discordance were discovered. These insights will inform the development and implementation of a mentorship programme that can be adapted for use by other oncology training programmes.

Top research priorities in liver and gallbladder disorders in the UK.

OBJECTIVES: There is a mismatch between research questions considered important by patients, carers and healthcare professionals and the research performed in many fields of medicine. The non-alcohol-related liver and gallbladder disorders priority setting partnership was established to identify the top research priorities in the prevention, diagnostic and treatment of gallbladder disorders and liver disorders not covered by the James-Lind Alliance (JLA) alcohol-related liver disease priority setting partnership. DESIGN: The methods broadly followed the principles of the JLA guidebook. The one major deviation from the JLA methodology was the final step of identifying priorities: instead of prioritisation by group discussions at a consensus workshop involving stakeholders, the prioritisation was achieved by a modified Delphi consensus process. RESULTS: A total of 428 unique valid diagnostic or treatment research questions were identified. A literature review established that none of these questions were considered 'answered' that is, high-quality systematic reviews suggest that further research is not required on the topic. The Delphi panel achieved consensus (at least 80% Delphi panel members agreed) that a research question was a top research priority for six questions. Four additional research questions with highest proportion of Delphi panel members ranking the question as highly important were added to constitute the top 10 research priorities. CONCLUSIONS: A priority setting process involving patients, carers and healthcare professionals has been used to identify the top 10priority areas for research related to liver and gallbladder disorders. Basic, translational, clinical and public health research are required to address these uncertainties.

Sensitivity and specificity of microRNA-122 for liver disease in dogs.

BACKGROUND: Current tests for diagnosing liver disease in dogs are sub-optimal. MicroRNA-122 (miR-122) is a sensitive and specific biomarker of liver injury in humans and rodents. Circulating miR-122 could have utility in identifying dogs with liver disease. OBJECTIVE: Establish the reference interval for miR-122 in healthy dogs and determine performance in a range of dog breeds with liver disease and control animals with non-liver disease. ANIMALS: Stored serum from 120 healthy dogs, 100 dogs with non-liver diseases, and 30 dogs with histologically confirmed liver disease was analyzed. METHODS: Retrospective study. Medical records of dogs with liver disease, non-liver disease and healthy dogs were reviewed. Serum miR-122 concentrations were measured by PCR and compared with the characteristics of the dogs and their conventional clinical measurements. RESULTS: In healthy dogs the 2.5th, 50th, and 97.5th quartiles of miR-122 were 110 (90% CI 80-114), 594 (505-682), and 3312 (2925-5144) copies/µL, respectively. There was no difference between healthy dogs and dogs with non-liver disease (median ± IQR: healthy dogs 609 [327-1014] copies/µL; non-liver disease 607 [300-1351] copies/µL). miR-122 was higher in dogs with liver disease (11 332 [4418-20 520] copies/µL, P < .001 compared to healthy dogs). miR-122 identified dogs with liver disease with high accuracy (receiver operating characteristic area under curve for comparison with healthy dogs: 0.93 [95% CI 0.86-0.99]). The upper limit of normal for healthy dogs (3312 copies/µL) had a sensitivity of 77% and specificity of 97% for identifying liver disease. CONCLUSION AND CLINICAL IMPORTANCE: Liver disease can be sensitively and specifically diagnosed in dogs by measurement of miR-122.

Immunohistochemical differentiation of reactive from malignant mesothelium as a diagnostic aid in canine pericardial disease.

OBJECTIVES: To develop a provisional immunohistochemistry panel for distinguishing reactive pericardium, atypical mesothelial proliferation and mesothelioma in dogs. MATERIALS AND METHODS: Archived pericardial biopsies were subject to haematoxylin and eosin staining, immunohistochemistry for cytokeratin, vimentin, insulin-like growth factor II mRNA-binding protein 3, glucose transporter 1 and desmin. Samples were scored for intensity and number of cells stained. RESULTS: Ten biopsies of reactive mesothelium, 17 of atypical mesothelial proliferation, 26 of mesothelioma and five of normal pericardium were identified on the basis of haematoxylin and eosin staining. Cytokeratin and vimentin were expressed in all biopsies, confirming mesothelial origin. Normal pericardial samples had the lowest scores for insulin-like growth factor II mRNA-binding protein 3, glucose transporter 1 and desmin. Mesothelioma and atypical proliferative samples were similar to each other, with higher scores for insulin-like growth factor II mRNA-binding protein 3 and glucose transporter 1 than the reactive samples. Desmin staining was variable. Insulin-like growth factor II mRNA-binding protein 3 was the best to distinguish between disease groups. CLINICAL SIGNIFICANCE: An immunohistochemistry panel of cytokeratin, vimentin, insulin-like growth factor II mRNA-binding protein 3 and glucose transporter 1 could provide superior information compared with haematoxylin and eosin staining alone in the diagnosis of cases of mesothelial proliferation in canine pericardium, but further validation is warranted.

Vitamin D Receptor Expression in Dogs.

BACKGROUND: There is growing evidence linking low blood vitamin D concentration to numerous diseases in people and in dogs. Vitamin D influences cellular function by signaling through the vitamin D receptor (VDR). Little is known about which non-skeletal tissues express the VDR or how inflammation influences its expression in the dog. OBJECTIVES: To define which non-skeletal canine tissues express the VDR and to investigate expression in inflamed small intestine. ANIMALS: Thirteen non-skeletal tissues were collected prospectively from 6 control dogs. Thirty-five dogs diagnosed with a chronic enteropathy (CE) and 24 control dogs were prospectively enrolled and duodenal biopsies were evaluated for VDR expression. METHODS: Prospective; blinded assessment of canine intestinal VDR. Dogs with CE were included once other identifiable causes of intestinal disease were excluded. Age matched controls were included with no intestinal clinical signs. VDR expression was assessed immunohistochemically in all samples, using a Rat IgG VDR monoclonal antibody. Quantitative real-time polymerase chain reaction (qPCR) was also used for duodenal biopsies. RESULTS: VDR expression as assessed by immunohistochemistry (IHC) was highest in the kidney, duodenum, skin, ileum and spleen, and weak in the colon, heart, lymph node, liver, lung, and ovary. Gastric and testicular tissue did not express the VDR. There was no statistical difference in duodenal VDR expression between the 24 healthy dogs and 34 dogs with CE when quantified by either qPCR (P = 0.87) or IHC (P = 0.099). CONCLUSIONS AND CLINICAL IMPORTANCE: The lack of down regulation of VDR expression in inflamed intestine contrasts with previous studies in humans. Our findings support future studies to investigate whether vitamin D and its analogues can be used to modulate intestinal inflammation in the dog.

Impact of high-fidelity e-learning on knowledge acquisition and satisfaction in radiation oncology trainees.

Background: e-Learning is an underutilized tool in education for the health professions, and radiation medicine, given its reliance on technology for clinical practice, is well-suited to training simulation in online environments. The purpose of the present study was to evaluate the knowledge impact and user interface satisfaction of high-(hf) compared with low-fidelity (lf) e-learning modules (e-modules) in radiation oncology training. Methods: Two versions of an e-module on lung radiotherapy (lf and hf) were developed. Radiation oncology residents and fellows were invited to be randomized to complete either the lf or the hf module through individual online accounts over a 2-week period. A 25-item multiple-choice knowledge assessment was administered before and after module completion, and user interface satisfaction was measured using the Questionnaire for User Interaction Satisfaction (quis) tool. Results: Of 18 trainees, 8 were randomized to the lf module, and 10, to the hf module. Overall, knowledge assessment performance increased (11%, p < 0.05), with hf-group participants reporting a 13% improvement (p = 0.02), and senior participants reporting an almost 15% improvement (p < 0.01). Scores on the quis indicated that participants were satisfied with various aspects of the user interface. Conclusions: The hf e-module had a greater impact on knowledge acquisition, and users expressed satisfaction with the interface in both the hf and lf situations. The use of e-learning in a competency-based curriculum could have educational advantages; participants expressed benefits and drawbacks. Preferences for e-learning integration in education for the health professions should be explored further.

Histological assessment of ß-amyloid precursor protein immunolabelled rectal biopsies aids diagnosis of equine grass sickness.

BACKGROUND: An accurate, minimally invasive, ante-mortem diagnostic test for equine grass sickness (EGS) is currently lacking. Although histological examination of haematoxylin and eosin-stained rectal biopsies for chromatolytic neurons is insensitive as a diagnostic test for EGS, we hypothesised that its diagnostic accuracy could be improved by immunolabelling for ß-amyloid precursor protein (ß-APP), which has increased expression in cranial cervical ganglia (CCG) neuronal perikarya in EGS. OBJECTIVES: To develop a grading scheme for assessing the distribution and intensity of ß-APP immunoreactivity within individual rectal submucosal neurons and subsequently to determine the value of the distribution of different grades of neurons in EGS diagnosis. STUDY DESIGN: Retrospective case-control diagnostic accuracy study. METHODS: Initially, a standardised grading scheme was developed and ß-APP immunoreactivity in individual neuronal perikarya and axons was compared in sections of CCG and ileum from EGS and control horses. The grading scheme was then refined before being blindly applied to submucosal neurons in rectal biopsies derived from 21 EGS and 23 control horses. RESULTS: ß-APP immunoreactivity was increased in neuronal perikarya and axons in sections of CCG, ileum and rectum from EGS horses compared with controls. For rectal biopsies, a mean immunoreactivity grade exceeding 1.1 was 100% specific and sensitive for EGS, and the presence of at least one neuron with diffuse labelling of the entire cytoplasm (grade 3) was 95% sensitive and 100% specific for EGS. MAIN LIMITATIONS: Although the diagnostic criteria facilitated the discrimination of the EGS and control biopsies evaluated in this study, further prospective validation using a larger sample set is required. CONCLUSIONS: Histological assessment of ß-APP immunolabelled rectal biopsies is more sensitive than conventional histological examination in EGS diagnosis. Further validation is required before this technique can be advocated for use in clinical decision making.

Consent - an update.

Following the judgement in Montgomery in March 2015 which brought the law of consent up to speed with what the GDC 's ethical and professional guidance expected registrants to do, this article looks at how other cases have interpreted Montgomery subsequently and the impact and implications for dentists. The importance of excellent communication is emphasised in order to provide sufficient and relevant information to the particular patient you have sitting in your dental chair.

Host-pathogen dynamics of squirrelpox virus infection in red squirrels (Sciurus vulgaris).

To improve our understanding of squirrelpox virus (SQPV) infection in the susceptible host, three red squirrels were challenged with wild-type SQPV via scarification of the hind-limb skin. All squirrels seroconverted to the infection by the end of the experiment (17 days post-challenge). Challenged animals suffered disease characterised by the development of multiple skin and oral lesions with rapid progression of skin lesions at the infection site by day 10 post-challenge. No internal pathological changes were found at post-mortem examination. A novel SQPV Taqman(®) Real-time PCR detected viral DNA from multiple organs, with the largest amounts consistently associated with the primary and secondary skin and oral lesions where viral replication was most likely occurring. Immunohistochemistry clearly detected viral antigen in the stratified squamous epithelium of the epidermis, tongue and the oropharyngeal mucosa-associated lymphoid tissue and was consistently associated with histological changes resulting from viral replication. The lack of internal pathological changes and the detection of relatively low levels of viral DNA when compared with primary and secondary skin lesions argue against systemic disease, although systemic spread of the virus cannot be ruled out. This study allowed a comprehensive investigation of the clinical manifestation and progression of SQPV infection with a quantitative and qualitative analysis of virus dissemination and shedding. These findings suggest two separate routes of SQPV transmission under natural conditions, with both skin and saliva playing key roles in infected red squirrels.

Equine grass sickness, but not botulism, causes autonomic and enteric neurodegeneration and increases soluble N-ethylmaleimide-sensitive factor attachment receptor protein expression within neuronal perikarya.

REASONS FOR PERFORMING STUDY: Equine grass sickness (EGS) is of unknown aetiology. Despite some evidence suggesting that it represents a toxico-infection with Clostridium botulinum types C and/or D, the effect of EGS on the functional targets of botulinum neurotoxins, namely the soluble N-ethylmaleimide-sensitive factor attachment receptor (SNARE) proteins, is unknown. Further, while it is commonly stated that, unlike EGS, equine botulism is not associated with autonomic and enteric neurodegeneration, this has not been definitively assessed. OBJECTIVES: To determine: 1) whether botulism causes autonomic and enteric neurodegeneration; and 2) the effect of EGS on the expression of SNARE proteins within cranial cervical ganglion (CCG) and enteric neuronal perikarya. STUDY DESIGN: Descriptive study. METHODS: Light microscopy was used to compare the morphology of neurons in haematoxylin-eosin stained sections of CCG and ileum from 6 EGS horses, 5 botulism horses and 6 control horses. Immunohistochemistry was used to compare the expression of synaptosomal-associated protein-25, synaptobrevin (Syb) and syntaxin within CCG neurons, and of Syb in enteric neurons, from horses with EGS, horses with botulism and control horses. The concentrations of these SNARE proteins in extracts of CCG from EGS and control horses were compared using quantitative fluorescent western blotting. RESULTS: EGS, but not botulism, was associated with autonomic and enteric neurodegeneration and with increased immunoreactivity for SNARE proteins within neuronal perikarya. Quantitative fluorescent western blotting confirmed increased concentrations of synaptosomal-associated protein-25, Syb and syntaxin within CCG extracts from EGS vs. control horses, with the increases in the latter 2 proteins being statistically significant. CONCLUSIONS: The occurrence of autonomic and enteric neurodegeneration, and increased expression of SNARE proteins within neuronal perikarya, in EGS but not botulism, suggests that EGS may not be caused by botulinum neurotoxins. Further investigation of the aetiology of EGS is therefore warranted.

Association of Vitamin D Status and Clinical Outcome in Dogs with a Chronic Enteropathy.

BACKGROUND: Dogs with a chronic enteropathy (CE) have a lower vitamin D status, than do healthy dogs. Vitamin D status has been associated with a negative clinical outcome in humans with inflammatory bowel disease. OBJECTIVES: To examine the relationship between serum 25 hydroxyvitamin D (25(OH)D) concentrations at diagnosis and clinical outcome in dogs with a CE. ANIMALS: Forty-one dogs diagnosed with CE admitted to the Royal Dick School of Veterinary Studies, Hospital for Small Animals between 2007 and 2013. METHODS: Retrospective review. Serum 25(OH)D concentrations were compared between dogs which were alive at follow up or had died because of non-CE-related reasons (survivors) and dogs which died or were euthanized due to their CE (non-survivors). A binary logistic regression analysis was performed to determine significant predictors of death in dogs with CE. RESULTS: Serum concentrations of 25(OH)D at the time a CE was diagnosed were significantly lower in nonsurvivors (n = 15) (median nonsurvivors 4.36 ng/mL, interquartile range 1.6-17.0 ng/mL), median survivors (n = 26) (24.9 ng/mL interquartile range 15.63-39.45 ng/mL, P < .001). Serum 25(OH)D concentration was a significant predictor of death in dogs with CE (odds ratio 1.08 [95% CI 1.02-1.18)]). CONCLUSIONS: Serum 25(OH)D concentrations at diagnosis are predictive of outcome in dogs with CE. The role of vitamin D in the initiation and outcome of chronic enteropathies in dogs is deserving of further study.

Better health at work? An evaluation of the effects and cost-benefits of a structured workplace health improvement programme in reducing sickness absence.

BACKGROUND: This paper presents the results of an evaluation of the Better Health at Work Award-a structured regional workplace health programme which combined changes to the work environment with lifestyle interventions. METHODS: Baseline and follow-up data on sickness-absence rates and programme costs were collected retrospectively via a web survey of all participating organizations. Changes over time were calculated using 95% confidence intervals of the mean, supplemented by hypothesis testing using a t-test. The indicative cost-benefits of the intervention were also calculated. RESULTS: Participation was associated with a mean reduction in sickness absence of 0.26-1.6 days per employee per year depending on the length and level of participation in the programme. The estimated cost for the programme was £3 per sickness-absence day saved. CONCLUSIONS: These results suggest that the Better Health at Work Award could be a cost-effective way of improving health and reducing sickness absence particularly in the public sector. However, controlled evaluations of future interventions are needed.

Childhood brain tumours: associations with parental occupational exposure to solvents.

BACKGROUND: Parental occupational exposures have been associated with childhood brain tumours (CBT), but results are inconsistent. Few studies have studied CBT risk and parental solvent exposure, suggesting a possible association. We examined the association between CBT and parental occupational exposure to solvents in a case-control study. METHODS: Parents of 306 cases and 950 controls completed detailed occupational histories. Odds ratios (ORs) and 95% confidence intervals (CIs) were estimated for both maternal and paternal exposure to benzene, other aromatics, aliphatics and chlorinated solvents in key time periods relative to the birth of their child. Adjustments were made for matching variables (child's age, sex and state of residence), best parental education and occupational exposure to diesel exhaust. RESULTS: An increased risk of CBT was observed with maternal occupational exposures to chlorinated solvents (OR=8.59, 95% CI 0.94-78.9) any time before birth. Paternal exposure to solvents in the year before conception was associated with an increased CBT risk: OR=1.55 (95% CI 0.99-2.43). This increased risk appeared to be mainly attributable to exposure to aromatic solvents: OR=2.72 (95% CI 0.94-7.86) for benzene and OR=1.76 (95% CI 1.10-2.82) for other aromatics. CONCLUSIONS: Our results indicate that parental occupational exposures to solvents may be related to an increased risk of CBT.