Genome-wide association studies of parasite resistance, productivity and immunology traits in Scottish Blackface sheep.

Gastrointestinal parasitism represents a global problem for grazing ruminants, which can be addressed sustainably by breeding animals to be more resistant against infection by parasites. The aim of this study was to assess the genetic architecture underlying traits associated with gastrointestinal parasite resistance, immunological profile and production in meat sheep, and identify and characterise candidate genes affecting these traits. Data on gastrointestinal parasite infection (faecal egg counts for Strongyles (FECS) and Nematodirus (FECN) and faecal oocyst counts for Coccidia, along with faecal soiling scores (DAG), characterised by the accumulation of faeces around the perineum) and production (live weight (LWT)) were gathered from a flock Scottish Blackface lambs at three and four months of age. Data on the immune profile were also collected from a subset of these lambs at two and five months of age. Immune traits included the production of Interferon-γ (IFN-γ), Interleukin (IL)-4 and IL-10 following stimulation of whole blood with pokeweed mitogen (PWM) or antigen from the gastric parasite Teladorsagia circumcincta (T-ci), and serum levels of T. circumcincta-specific immunoglobulin A (IgA). Animals were genotyped with genome-wide DNA arrays, and a total of 1 766 animals and 45 827 Single Nucleotide Polymorphisms (SNPs) were retained following quality control and imputation. Genome-wide association studies were performed for 24 traits. The effects of individual markers with significant effects were estimated, and the genotypic effect solutions were used to estimate additive and dominance effects, and the proportion of additive genetic variance attributed to each SNP locus. A total of 15 SNPs were associated at least at a suggestive level with FECS, FECN, DAG, IgA, PWM-induced IFN-γ and IL-4, and T-ci-induced IL-10. This study uncovered 52 genes closely related to immune function in proximity to these SNPs. A number of genes encoding C-type lectins and killer cell lectin-like family members were close to a SNP associated with FECN, while several genes encoding IL-1 cytokine family members were found to be associated with IgA. Potential candidate genes belonging to or in close proximity with the Major Histocompatibility Complex (MHC) were revealed, including Homeostatic Iron Regulator and butyrophilin coding genes associated with IFN-γ(PWM), and IL-17 coding genes associated with IgA. Due to the importance of the MHC in the control of immune responses, these genes may play an important role in resistance to parasitic infections. Our results reveal a largely complex and polygenic genetic profile of the studied traits in this Scottish Blackface sheep population.

Thyroid lobectomy for low-risk thyroid cancers.

BACKGROUND: The 2016 American Thyroid Association (ATA) guidelines proposed thyroid lobectomy for low-risk differentiated thyroid cancer (DTC); however, this approach is yet to be widely adopted. The aim of the study was to review our practice over three years following the publication of these guidelines identifying patients who underwent lobectomy-only for low-risk DTC in two regional units in the same multidisciplinary team (MDT). METHOD: A retrospective review of patients who were operated between January 2016 and December 2018 was carried out. RESULTS: In total, 288 patients undergoing thyroid surgery were included. The preoperative distribution of cytology was: Thy 1 or 2 in 46, THY3a in 57, THY3f in 154, THY4 in 18 and THY5 in 13 patients. Median size of nodules was 26mm (range 1-70mm). DTC was diagnosed in 95 patients (33%). Overall, 39% (n = 37) of patients underwent completion thyroidectomy according to ATA recommendations on size or adverse histological features. The only variable associated with likelihood of completion was tumour size (p < 0.05, OR 1.14). Ten patients were discharged following surgery with no further follow-up as they had T1a/b well-differentiated DTC with no high-risk histological features. CONCLUSION: Lobectomy-only appears to be the current surgical practice in two-thirds of patients presenting to our regional units with differentiated thyroid carcinoma. In the context of the current drive to reduce the extent of treatment for low-risk thyroid cancer, there is a need for a more homogeneous approach to these patients and for protocols for long-term follow-up after lobectomy-only.

Metastatic seminoma with isolated gastric metastases: a case report.

Gastric metastases are a rare occurrence in patients with malignancy. In case reports of these arising from germ cell tumours, the majority were non-seminomatous germ cell tumours and had evidence of retroperitoneal involvement. We present a unique case of a 67-year-old man with metastatic testicular pure seminoma. He presented with dyspepsia and investigation found isolated metastases to the gastric mucosa and sub-mucosa from a right testicular primary. No lymph node involvement was identified. The patient was managed with curative intent with total gastrectomy and inguinal orchidectomy. To date, there is no evidence of disease recurrence.

An Extensively Humanized Mouse Model to Predict Pathways of Drug Disposition and Drug/Drug Interactions, and to Facilitate Design of Clinical Trials.

Species differences in drug metabolism and disposition can confound the extrapolation of in vivo PK data to man and also profoundly compromise drug efficacy studies owing to differences in pharmacokinetics, in metabolites produced (which are often pharmacologically active), and in differential activation of the transcription factors constitutive androstane receptor (CAR) and pregnane X receptor (PXR), which regulate the expression of such enzymes as P450s and drug transporters. These differences have gained additional importance as a consequence of the use of genetically modified mouse models for drug-efficacy testing and also patient-derived xenografts to predict individual patient responses to anticancer drugs. A number of humanized mouse models for cytochrome P450s, CAR, and PXR have been reported. However, the utility of these models has been compromised by the redundancy in P450 reactions across gene families, whereby the remaining murine P450s can metabolize the compounds being tested. To remove this confounding factor and create a mouse model that more closely reflects human pathways of drug disposition, we substituted 33 murine P450s from the major gene families involved in drug disposition, together with Car and Pxr, for human CAR, PXR, CYP1A1, CYP1A2, CYP2C9, CYP2D6, CYP3A4, and CYP3A7. We also created a mouse line in which 34 P450s were deleted from the mouse genome. Using model compounds and anticancer drugs, we demonstrated how these mouse lines can be applied to predict drug-drug interactions in patients and discuss here their potential application in the more informed design of clinical trials and the personalized treatment of cancer.

New mastitis phenotypes suitable for genomic selection in meat sheep and their genetic relationships with udder conformation and lamb live weights.

Mastitis can prove expensive in sheep reared for meat production due to costs associated with treatment methods, poor lamb growth and premature culling of ewes. The most commonly used method to detect mastitis, in dairy systems, is somatic cell counts. However, in many meat-producing sheep flocks ewes are not routinely handled, thus regular milk sampling is not always possible. It is, therefore, worthwhile to investigate alternative phenotypes, such as those associated with udder conformation and methods of evaluating somatic cell counts in the milk, such as the California Mastitis Test. The main objectives of this study were therefore: (a) to estimate genetic parameters of traits relating to mastitis and udder conformation in a meat sheep breed; (b) estimate the level of association between somatic cell counts and the California Mastitis Test and (c) assess the relationships between mastitis and both udder conformation and lamb live weights. Data were collected from Texel ewes based on 29 flocks, throughout the UK, during 2015 and 2016. The ewes were scored twice each year, at mid- and late-lactation. Eight different conformation traits, relating to udder and teat characteristics, and milk samples were recorded. The data set comprised of data available for 2957 ewes. The pedigree file used contained sire and dam information for 31 775 individuals. The animal models used fitted relevant fixed and random effects. Heritability estimates for traits relating to mastitis (somatic cell score and the California Mastitis Test), ranged from 0.08 to 0.11 and 0.07 to 0.11, respectively. High genetic correlations were observed between somatic cell score and the California Mastitis Test (0.76 to 0.98), indicating the California Mastitis Test to be worthwhile for assessing infection levels, particularly at mid-lactation. The strongest correlations observed between the mastitis traits and the udder conformation traits were associated with udder depth (0.61 to 0.75) also at mid-lactation. Negative phenotypic correlations were estimated between mastitis and the weight of lamb reared by the ewe (-0.15 to -0.23), suggesting that lamb weights fell as infection levels rose. Genetic correlations were not significantly different from zero. Reducing mastitis will lead to improvements in flock productivity and the health and welfare of the animals. It will also improve the efficiency of production and the resilience to disease challenge. The economic benefits, therefore, of these results combined could be substantial not only in this breed but also in the overall meat sheep industry.

Wound healing outcomes in a diabetic foot ulcer outpatient clinic at an acute care hospital: a retrospective study.

OBJECTIVE: Patients with diabetic foot ulcers (DFU) have an increased risk of lower extremity amputation. A retrospective chart review of patients with DFUs attending the Foot Treatment and Assessment chiropodist-led outpatient clinic at an inner-city academic hospital was conducted to determine wound healing outcomes and characteristics contributing to outcomes. METHOD: We reviewed the complete clinical history of 279 patients with 332 DFUs spanning over a five-year period. RESULTS: The mean age of patients was 61.5±12.5 years and most patients (83.5%) had one DFU. The majority of wounds (82.5%) were in the forefoot. Overall, 267/332 (80.5%) wounds healed. A greater proportion of wounds healed in the forefoot (82.5%) and midfoot (87.1%) than hindfoot (51.9%; p<0.001). Using a logistic regression model, palpable pedal pulse and use of a total contact cast were associated with better wound healing. CONCLUSION: Our findings are the first to demonstrate the benefits of chiropodists leading an acute care outpatient clinic in the management of DFUs in Canada and delivers wound healing outcomes equivalent to or exceeding those previously published.

Postoperative complications after head and neck operations that require free tissue transfer - prevalent, morbid, and costly.

To understand and reduce the impact of postoperative complications, we studied 568 patients who had had operations over 72 months in our hospital. Multivariate analysis indicated that factors indicative of coexisting conditions (including activated systemic inflammation) and the complexity of the operation are primary determinants of postoperative complications. The enhanced recovery after surgery (ERAS) care pathway did not have an effect on their occurrence or severity. Systematic study of patients' toleration of major head and neck operations is required, as optimal perioperative care pathways remain elusive.

Genetic parameters of linear conformation type traits and their relationship with milk yield throughout lactation in mixed-breed dairy goats.

Conformation traits are of interest to many dairy goat breeders not only as descriptive traits in their own right, but also because of their influence on production, longevity, and profitability. If these traits are to be considered for inclusion in future dairy goat breeding programs, relationships between them and production traits such as milk yield must be considered. With the increased use of regression models to estimate genetic parameters, an opportunity now exists to investigate correlations between conformation traits and milk yield throughout lactation in more detail. The aims of this study were therefore to (1) estimate genetic parameters for conformation traits in a population of crossbred dairy goats, (2) estimate correlations between all conformation traits, and (3) assess the relationship between conformation traits and milk yield throughout lactation. No information on milk composition was available. Data were collected from goats based on 2 commercial goat farms during August and September in 2013 and 2014. Ten conformation traits, relating to udder, teat, leg, and feet characteristics, were scored on a linear scale (1-9). The overall data set comprised data available for 4,229 goats, all in their first lactation. The population of goats used in the study was created using random crossings between 3 breeds: British Alpine, Saanen, and Toggenburg. In each generation, the best performing animals were selected for breeding, leading to the formation of a synthetic breed. The pedigree file used in the analyses contained sire and dam information for a total of 30,139 individuals. The models fitted relevant fixed and random effects. Heritability estimates for the conformation traits were low to moderate, ranging from 0.02 to 0.38. A range of positive and negative phenotypic and genetic correlations between the traits were observed, with the highest correlations found between udder depth and udder attachment (0.78), teat angle and teat placement (0.70), and back legs and back feet (0.64). The genetic correlations estimated between conformation traits and milk yield across the first lactation demonstrated changes during this period. The majority of correlations estimated between milk yield and the udder and teat traits were negative. Therefore, future breeding programs would benefit from including these traits to ensure that selection for increased productivity is not accompanied by any unwanted change in functional fitness.

The effects of different farm environments on the performance of Texel sheep.

In order to assess the extent of genotype by environment interactions (G×E) and environmental sensitivity in sheep farm systems, environmental factors must be identified and quantified, after which the relationship with the traits(s) of interest can be investigated. The objectives of this study were to develop a farm environment (FE) scale, using a canonical correlation analysis, which could then be used in linear reaction norm models. Fine-scale farm survey data, collected from a sample of 39 Texel flocks across the United Kingdom, was combined with information available at the national level. The farm survey data included information on flock size and concentrate feed use. National data included flock performance averages for 21-week-old weight (21WT), ultrasound back-fat (UFD) and muscle (UMD) depths, as well as regional climatic data. The FE scale developed was then combined with 181 555 (21WT), 175 399 (UMD) and 175 279 (UFD) records from lambs born between 1990 and 2011, on 494 different Texel flocks, to predict reaction norms for sires used within the population. A range of sire sensitivities estimated across the FE scale confirmed the presence of genetic variability as both 'plastic' and 'robust' genotypes were observed. Variations in heritability estimates were also observed indicating that the rate genetic progress was dependent on the environment. Overall, the techniques and approaches used in this study have proven to be useful in defining sheep FEs. The results observed for 21WT, UMD and UFD, using the reaction norm models, indicate that in order to improve genetic gain and flock efficiency, future genetic evaluations would benefit by accounting for the G×E observed.

Characterisation of terminal sire sheep farm systems, based on a range of environmental factors: a case study in the context of genotype by environment interactions using Charollais lambs.

The objective of this study was to define different terminal sire flock environments, based on a range of environmental factors, and then investigate the presence of genotype by environment interactions (G×E) between the environments identified. Data from 79 different terminal sire flocks (40 Texel, 21 Charollais and 18 Suffolk), were analysed using principal coordinate and non-hierarchical cluster analyses, the results of which identified three distinct environmental cluster groups. The type of grazing, climatic conditions and the use of vitamins and mineral supplements were found to be the most important factors in the clustering of flocks. The presence of G×E was then investigated using data from the Charollais flocks only. Performance data were collected for 12 181 lambs, between 1990 and 2010, sired by 515 different sires. Fifty six of the sires had offspring in at least two of the three different cluster groups and pedigree information was available for a total of 161 431 animals. Traits studied were the 21-week old weight (21WT), ultrasound muscle depth (UMD) and log transformed backfat depth (LogUFD). Heritabilities estimated for each cluster, for each trait, ranged from 0.32 to 0.45. Genetic correlations estimated between Cluster 1 and Cluster 2 were all found to be significantly lower than unity, indicating the presence of G×E. They were 0.31 (±0.17), 0.68 (±0.14) and 0.18 (±0.21) for 21WT, UMD and LogUFD, respectively. Evidence of sires re-ranking across clusters was also observed. Providing a suitable strategy can be identified, there is potential for the optimisation of future breeding programmes, by taking into account the G×E observed. This would enable farmers to identify and select animals with an increased knowledge as to how they will perform in their specific farm environment thus reducing any unexpected differences in performance.

Luxatio erecta of the hip.

We present the case of a young male patient with inferior dislocation of the hip and postulate a possible mechanism for this extremely rare injury.

Three-year audit and cost assessment of open abdominal aortic aneurysm repair in a district general hospital.

INTRODUCTION: The aims of this study were to audit the outcome of elective open abdominal aortic aneurysm (AAA) repair in a district general hospital, as well as investigate the true costs for this procedure in relation to the national tariff. PATIENTS AND METHODS: A database is maintained on AAA surgery in the trust. Data were supplemented by drawing information from blood bank and clinical notes. Patients with symptomatic or emergency aneurysms were excluded. Data from January 2005 to December 2007 were obtained on demographics, morbidity, 30-day mortality and blood usage. Costs were obtained from the trust finance department. RESULTS: Between January 2005 and December 2007, 79 elective AAA procedures were undertaken. Median age was 75 years (range, 52-85 years), median aneurysm size was 63 mm (range, 42-105 mm) and median ITU stay was 3 days (range, 1-41 days). Major morbidity rate was 20.3% (16 of 79 patients) and 30-day mortality overall was 5.1% (4 of 79 patients). Average cost per case was pound15,012.91 (range, pound4,040.03- pound82,158.00), when National Tariff is pound6,722.00 ( pound5,649.00 x local Market Forces Factor of 1.19). Loss per case for our trust was pound8,290.91 with a total annual loss of pound218,299.56. CONCLUSIONS: Morbidity and mortality in this district general hospital compare well with national studies; however, the total cost is far in excess of the national tariff.

Generic tobramycin elutes from bone cement faster than proprietary tobramycin.

Elution of antibiotics from antibiotic-loaded polymethylmethacrylate (AL-PMMA) increases when soluble particulate filler is added to increase the permeability of the PMMA. Antibiotic powder is in itself soluble particulate filler. For greater volume fractions of filler, greater elution occurs. The volume of generic tobramycin powder is more than 3.5 times the volume of proprietary tobramycin powder for a 1.2 g dose leading to the question: Does generic tobramycin elute from AL-PMMA faster than proprietary tobramycin? We performed elution studies on AL-PMMA beads made with 1.2 g of either generic tobramycin or proprietary tobramycin per batch of PMMA. Generic tobramycin eluted more than two times faster than proprietary tobramycin. The release mechanism started as dissolution-driven zero-order release for the generic bead set but for the proprietary bead set the released mechanism started as anomalous diffusion. The release mechanism progressed to diffusion-driven first-order release in both. The increased volume of the generic tobramycin caused more tobramycin to be available for release. The increased elution of tobramycin associated with the greater volume of generic tobramycin powder could lead to clinically higher levels of tobramycin in wound fluid and local tissues; however, the higher volume of powder could potentially cause greater mechanical compromise of the PMMA.

Storage of strain-specific rat blood limits cerebral tissue oxygen delivery during acute fluid resuscitation.

BACKGROUND: The effect of blood storage on tissue oxygen delivery has not been clearly defined. Some studies demonstrate reduced microvascular oxygen delivery, whereas others do not. We hypothesize that storage of rat blood will limit its ability to deliver oxygen to cerebral tissue. METHODS: Anaesthetized rats underwent haemorrhage (18 ml kg(-1)) and resuscitation with an equivalent amount of fresh or 7 day stored strain-specific whole blood. Arterial blood gases, co-oximetry, red cell counts and indices, and blood smears were performed. Hippocampal tissue oxygen tension (PBr(O2)), regional cerebral blood flow (rCBF), and mean arterial pressure (MAP) were measured before and for 60 min after resuscitation (n=6). Data [mean (SD)] were analysed by anova. RESULTS: After 7 days, there was a significant reduction in pH, Pa(O2), an increase in Pa(CO2), but no detectable plasma haemoglobin in stored rat blood. Stored red blood cell morphology demonstrated marked echinocytosis, but no haemolysis in vitro. MAP and PBr(O2) in both groups decreased after haemorrhage. Resuscitation with stored blood returned MAP [92 (SD 16) mm Hg] and PBr(O2) [3.2 (0.7) kPa] to baseline, whereas rCBF remained stable [1.2 (0.1)]. Resuscitation with fresh blood returned MAP to baseline [105 (16) mm Hg] whereas both PBr(O2) [5.6 (1.5) kPa] and rCBF [1.9 (0.4)] increased significantly (P<0.05 for both, relative to baseline and stored blood group). There was no evidence of haemolysis in vivo. CONCLUSIONS: Although resuscitation with stored blood restored cerebral oxygen delivery to baseline, fresh blood produced a greater increase in both PBr(O2) and rCBF. These data support the hypothesis that storage limits the ability of RBC to deliver oxygen to brain tissue.

Relationships between lamb carcass quality traits measured by X-ray computed tomography and current UK hill sheep breeding goals.

Genetic parameters were estimated between current UK hill sheep breeding goals and lamb carcass composition and muscularity traits derived using X-ray computed tomography (CT). To produce these estimates, a total of 648 lambs from two hill farms were CT scanned at weaning (ca 120 days of age), over 3 years, and total weights of carcass muscle (MUSC), fat (CFAT) and bone (BONE) and internal fat (IFAT) were predicted. Previously derived muscularity indices were also calculated for the hind leg (HLMI) and lumbar (LRMI) regions, to assess muscle shape. Data for current breeding goals (lamb performance and maternal traits) were also included from a total of 10 297 lamb records and 12 704 ewe records. Heritabilities were estimated for each trait and genetic and phenotypic correlations were calculated between each CT trait and other lamb or ewe traits. Moderate to high positive genetic correlations were found between CT-predicted tissue weights and breeding goals, which were also weights (lamb weaning weight, carcass weight, mature ewe weight, average weight of lambs reared by the ewe). CFAT was positively genetically correlated with ultrasound backfat depth at weaning (UFD) and subjective fatness grade at slaughter (MLCF), suggesting that carcass fat could be decreased using selection on any of these predictors. Ultrasound muscle depth at weaning (UMD) and subjective conformation score at slaughter (MLCC) had high genetic correlations with the muscularity indices (HLMI and LRMI), but correlations with MUSC were not significantly different from zero. This implies that selection to improve MLCC is likely to be increasing the 'roundness' of muscle shape in the high-priced carcass region, but having little impact on total lean meat yield. Correlations of CT traits with the other ewe traits (number of lambs weaned, number of lambs lost, longevity, fleece weight) were generally small or not significantly different from zero. The genetic parameters generated in this study can now be used in selection index calculations to assess the benefits of including lamb CT traits in future selection programmes for hill sheep.

Particle size of fillers affects permeability of polymethylmethacrylate.

Particulate soluble filler added to polymethylmethacrylate increases its permeability, leading to increased elution. We asked whether particle size affects permeability and elution rate associated with a given volume fraction of filler. Permeability of filler-loaded PMMA was measured in 9 mm rods with a 32% volume fraction of four particle sizes (106 microm, 212 microm, 425 microm, 850 microm) and two filler materials (sucrose and xylitol) using a modified phenolphthalein-sodium hydroxide technique, which allowed quantitative serial observation on the same specimens. Fluid penetration was faster for larger particle sizes. The elution rate was greater for smaller particle sizes on qualitative visual assessment. Sucrose fillers were not different from xylitol fillers independent of particle size. For the volume fraction of 32%, larger particles lead to larger caliber porosity, less pore interconnectivity, and faster fluid penetration. Smaller size particles lead to smaller caliber porosity, greater pore interconnectivity, smaller areas between the pores with no fluid penetration and greater increase in the effective surface area causing a greater elution rate.

Impact of hypertension and apolipoprotein E4 on poststroke cognition in subjects >75 years of age.

BACKGROUND AND PURPOSE: The apolipoprotein E4 allele (APOE4) associates with increased dementia risk, and hypertension may associate with mild cognitive deficits. We examined whether nondemented stroke patients with (1) a prestroke history of hypertension and (2) APOE4 were more cognitively impaired at 3 months after stroke. METHODS: A total of 257 participants were genotyped and outcomes from neuropsychological evaluations analyzed using regression. RESULTS: Total Cambridge Assessment for Mental Disorders in the Elderly (CAMCOG) and speed of working memory significantly associated with hypertension. No outcomes significantly associated with APOE4. CONCLUSIONS: Subjects with prestroke hypertension had more impaired global cognition and slower access to information held in working memory.

Autonomic function assessed by heart rate variability is normal in Alzheimer's disease and vascular dementia.

Heart rate variability (HRV) is a sensitive method for the assessment of autonomic function and requires little cooperation from the subject, making it suitable for use in dementia. Preliminary studies have suggested that HRV may be impaired in Alzheimer's disease (AD). HRV has not been studied in vascular dementia (VAD). We investigate autonomic function in AD and VAD, using power spectral analysis of HRV. One hundred and fourteen participants were evaluated (14 AD, 20 VAD and 80 controls). The resting ECG was recorded for 5 min with participants in the supine position. Power spectral analysis used to obtain spectral bands in the very-low-frequency (<0.04 Hz), low-frequency (0.04-0.15 Hz) and high-frequency (0.15-0.40 Hz) bands and total spectral power (<0.40 Hz) according to international HRV guidelines. There were no differences in HRV in patients with AD or VAD when compared with controls.

Potential clozapine target sites on peripheral hematopoietic cells and stromal cells of the bone marrow.

The antipsychotic drug clozapine, acts via interaction with selective neurotransmitter receptor systems. Its use however, is associated with life-threatening agranulocytosis. The mechanism by which this occurs and its possible relationship with the drug's atypicality remain unclear. As a first step in identifying mechanistic pathways involved, profiling of neurotransmitter receptors on human neutrophils, mononuclear and bone marrow stromal cells as putative targets for clozapine-mediated toxicity was undertaken. Expression of mRNA encoding dopaminergic d2, d3, d4; serotonergic 5ht2a, 5ht2c, 5ht3, 5ht6, 5ht7; adrenergic alpha1a, alpha2; histaminergic h1 and muscarinic m1, m2, m3, m4, m5 receptors was analyzed by reverse transcription-polymerase chain reaction methods. While 5ht2c, 5ht6, m1 and m2 mRNA were undetected, the presence of the other receptors indicates sites at which clozapine could bind and induce toxicity of neutrophils and stromal components which regulate granulopoiesis. The functional significance of differential receptor expression while unknown, may argue for neural regulation of hematopoiesis.