Type 2 diabetes remission 2 years post Roux-en-Y gastric bypass and sleeve gastrectomy: the role of the weight loss and comparison of DiaRem and DiaBetter scores.

AIMS: The comparative efficacy of Roux-en-Y gastric bypass (RYGB) and sleeve gastrectomy on Type 2 diabetes remission and the role of weight loss are unclear. The DiaRem diabetes remission prediction score uses HbA1c , age and diabetes medications but not diabetes duration. The aim of this study was to compare the DiaRem with the DiaBetter score that includes diabetes duration, upon combined (complete plus partial) 2-year post-surgery diabetes remission in people following RYGB and sleeve gastrectomy, and to investigate the relationship between weight loss and diabetes remission. METHODS: A retrospective single-centre cohort study of obese people with diabetes who underwent RYGB (107) or sleeve gastrectomy (103) and a validation cohort study (173) were undertaken. Diabetes remission, % weight loss, DiaRem, DiaBetter scores and areas under receiving operator characteristic (ROC) curves were calculated. The relationship between % weight loss and diabetes remission was investigated using logistic regression. RESULTS: The proportion of people achieving diabetes remission was highest for those with the lowest DiaBetter and DiaRem scores. Areas under the ROC curves were comparable [DiaBetter: 0.867 (95%CI: 0.817-0.916); DiaRem: 0.865 (95%CI: 0.814-0.915), P=0.856]. Two-year % weight loss was higher post RYGB [26.6 (95%CI: 24.8-28.4)] vs post-sleeve gastrectomy [20.6 (95%CI: 18.3-22.8), P<0.001]. RYGB had 151% higher odds of diabetes remission [OR 2.51 (95%CI: 1.12-5.60), P=0.025]. This association became non-significant when adjusted for % weight loss. CONCLUSION: DiaBetter and DiaRem scores predict diabetes remission following both procedures. Two-year % weight loss plays a key role in determining diabetes remission.

Brain lesions associated with clostridium perfringens type D epsilon toxin in a Holstein heifer calf.

A 6-month-old dairy heifer calf with no premonitory signs was acutely down after the morning feeding and could not rise. On presentation, the heifer was in right lateral recumbency and moribund with opisthotonus and left hind limb paddling. Following euthanasia, gross examination of the brain revealed multifocal loss of gray-white matter distinction and extensive petechiae throughout the brainstem. On histopathological examination, there was striking white matter edema and marked perivascular proteinaceous edema surrounding many arterioles and venules (microangiopathy), mainly in the white matter of the internal capsule, thalamus, midbrain, cerebellum, and cerebellar peduncles. The perivascular neuropil was strongly positive for Alzheimer precursor protein A4. Clostridium perfringens epsilon toxin was detected in the intestinal contents. This is the first report of microangiopathy in postneonatal cattle associated with the detection of epsilon toxin in the intestinal contents.

Identification of congenital muscular dystonia 2 associated with an inherited GlyT2 defect in Belgian Blue cattle from the United Kingdom.

Two newborn Belgian Blue calves from a farm in the United Kingdom exhibited lateral recumbency, low head carriage and transient muscle spasms following tactile or auditory stimulation. DNA sequence analysis indicated that both calves were homozygous for the recessive congenital muscular dystonia type 2 (CMD2) mutation (c.809T>C, p.Leu270Pro) in SLC6A5, encoding the neuronal glycine transporter GlyT2. Further testing of animals from the index farm and a sample of Belgian Blue sires revealed an unexpectedly high frequency of CMD2 carriers. This implies that linked quantitative trait loci may be influencing the prevalence of CMD2 in the estimated 55,000 Belgian Blue cattle in the United Kingdom. We have therefore developed new inexpensive tests for the CMD2 allele that can be used to confirm diagnosis, identify carriers and guide future breeding strategy, thus avoiding animal distress/premature death and minimizing the future economic impact of this disorder.

Selection of baseline blood pressure to guide management of hypotension during spinal anaesthesia for caesarean section.

INTRODUCTION: Recommendations on vasopressor management during caesarean section under spinal anaesthesia suggest maintaining systolic arterial pressure ≥90% of an accurately measured baseline value. The baseline is often taken as the first reading in the operating room. We hypothesise that this reading may not reflect an accurate baseline value. METHODS: A retrospective case note review of 300 non-hypertensive women undergoing caesarean section with neuraxial anaesthesia, including spinal anaesthesia for elective delivery (n=100), and spinal (n=100) and epidural top-up anaesthesia (n=100) for emergency delivery. Systolic arterial pressure values recorded at various time points between the last antenatal visit and the first blood pressure value recorded in the operating room were compared. RESULTS: There was a stepwise and significant increase in systolic arterial pressure over three time points (last antenatal clinic, morning of surgery, operating room) before elective caesarean section (all P <0.001). In women having emergency caesarean under spinal anaesthesia, a stepwise increase over four time points (last antenatal clinic, first reading in labour, final reading in labour, operating room) was observed. A similar trend was seen over these time points for women having emergency caesarean under epidural top-up, although the systolic blood pressure did not rise during labour. CONCLUSIONS: Using the initial blood pressure reading in the operating room as the baseline value may lead to unnecessary vasopressor use and hypertension. Prospective research is required to clarify which reading represents the most accurate baseline to maintain homeostasis and reduce the hypotensive sequelae of neuraxial anaesthesia for both the mother and fetus.

Clinical, ultrasonographic and pathological findings in a bull with segmental aplasia of the mesonephric duct.

On assessment for use in an AI stud, a 12-month-old bull was found to produce low volume ejaculates with 41% of the sperm having morphological abnormalities. No left epididymal tail was palpable and the head of the epididymis on the left was twice the size compared with the right. Ultrasound examination showed the left testis to contain a large central area of decreased echogenicity, which could be followed proximally to a 15-mm echolucent lesion at the site of the epididymal head. Postmortem examination revealed a 15-mm diameter cyst in the region of the left epididymal head, and absence of the body and tail of the epididymis. The mediastinum testis of the left testis was dilated, corresponding to the area of decreased echogenicity observed on ultrasonography. No left seminal vesicle was present and the ampulla was significantly smaller than the same structure on the right. Histological examination revealed incomplete or absent spermatogenesis involving the majority of seminiferous tubules in the left testis, and a small proportion of those of the right testis. The cystic structure at the site of the left epididymal head was lined by irregular, sometimes attenuated, epithelium and contained sparse spermatozoa. This case demonstrates the adverse impact, which segmental aplasia of the mesonephric duct had on the testicular and epididymal function of a bull, and highlights the importance of careful clinical assessment in its diagnosis.

Pitch-based carbon-fibre-reinforced poly (ether-ether-ketone) OPTIMA assessed as a bearing material in a mobile bearing unicondylar knee joint.

The introduction of unicondylar knee prostheses has allowed the preservation of the non-diseased compartment of the knee while replacing the diseased or damaged compartment. In an attempt to reduce the likelihood of aseptic loosening, new material combinations have been investigated within the laboratory. Tribological tests (friction, lubrication, and wear) were performed on metal-on-carbon-fibre-reinforced (CFR) poly (ether-ether-ketone) (PEEK) (pitch-based) mobile unicondylar knee prostheses up to 5 x 10(6) cycles. Both a loaded soak control and an unloaded soak control (both medial and lateral components) were used to compensate for weight change due to lubricant absorption. For this material combination the loaded soak control gave slightly lower wear for both the medial and the lateral components than did the unloaded soak control. The medial components gave higher steady state wear than the lateral components (1.70 mm3 per 10(6) cycles compared with 1.02 mm3 per 10(6) cycles with the loaded soak control). The results show that the CFR PEEK unicondylar knee joints performed well in these wear tests. They gave lower volumetric wear rates than conventional metal-on-ultra-high-molecular-weight polyethylene prostheses have given in the past when tested under similar conditions. The friction tests showed that, at physiological viscosities, these joints operated in the boundary-mixed-lubrication regime. The low wear produced by these joints seems to be a function of the material combination and not of the lubrication regime.

Compliant layer bearings in artificial joints. Part 2: simulator and fatigue testing to assess the durability of the interface between an elastomeric layer and a rigid substrate.

Artificial joints have been much improved since their introduction but they still have a limited lifetime. In an attempt to increase their life by improving the lubrication acting within these prostheses, compliant layered polyurethane (PU) joints have been devised. These joints mimic the natural synovial joint more closely by promoting fluid film lubrication. In this study, tests were performed on compliant layer joints to determine their ability to function under a range of conditions. Both static and dynamic compression tests were undertaken on compliant artificial hip joints of two different radial clearances. Friction tests were also performed before and after static loading. In addition to this, knee wear tests were conducted to determine the suitability of a compliant layer in these applications. In the knee tests, variations in experimental testing conditions were investigated using both active and passive rotation and severe malalignment of the tibial inserts. The static compression tests together with the friction studies suggest that a small radial clearance is likely to result in 'grabbing' contact between the head and cup. The larger radial clearance (0.33 microm) did not exhibit these problems. The importance of the design of the compliant layer joints was highlighted with delamination occurring on the lateral bearings during the knee wear studies. The bearings with a layer 2 mm thick performed better than the bearings with a layer 3 mm thick. Tests conducted on flat PU bearings resulted in no delamination; therefore, it was concluded that the layer separation was caused by design issues rather than by material issues. It was found that, with careful material choice, consideration of design, and effective manufacturing techniques, the compliant layer joint functioned well and demonstrated durability of the union between the hard and soft layers. These results give encouragement for the suitability of these joints for clinical use.

Congenital tremor and hypomyelination associated with bovine viral diarrhoea virus in 23 British cattle herds.

This paper presents data from 23 British herds investigated between 1991 and 2007 where neurological disease in calves was caused by bovine viral diarrhoea virus (BVDV) infection. A variety of clinical signs, most commonly tremor or trembling, were apparent in the calves from birth, and most were recumbent or unable to stand unsupported. Severe diffuse neuraxial hypomyelination was present in all of the calves, and immunohistochemistry revealed cerebral neuronal labelling consistent with congenital persistent pestivirus infection in each brain. BVDV was detected in peripheral blood samples from eight of 15 calves tested using an antigen ELISA, and was isolated in culture from samples of viscera, brain or blood collected from 17 of 24 affected calves. TaqMan RT-PCR for pestivirus RNA was positive for BVDV-1 in all six calves tested. Six of the virus isolates on which molecular classification was carried out, obtained from calves in four of the herds, were identified as BVDV-1a, while three isolates from one affected and two unaffected calves on a fifth farm were confirmed as BVDV-1b.

Tribological assessment of a flexible carbon-fibre-reinforced poly(ether-ether-ketone) acetabular cup articulating against an alumina femoral head.

New material combinations have been introduced as the bearing surfaces of hip prostheses in an attempt to prolong their life by overcoming the problems of failure due to wear-particle-induced osteolysis. This will hopefully reduce the need for revision surgery. The study detailed here used a hip simulator to assess the volumetric wear rates of large-diameter carbon-fibre-reinforced pitch-based poly(ether-ether-ketone) (CFR-PEEK) acetabular cups articulating against alumina femoral heads. The joints were tested for 25 x 10(6) cycles. Friction tests were also performed on these joints to determine the lubrication regime under which they operate. The average volumetric wear rate of the CFR-PEEK acetabular component of 54 mm diameter was 1.16 mm(3)/10(6) cycles, compared with 38.6 mm(3)/10(6) cycles for an ultra-high-molecular-weight polyethylene acetabular component of 28 mm diameter worn against a ceramic head. This extremely low wear rate was sustained over 25 x 10(6) cycles (the equivalent of up to approximately 25 years in vivo). The frictional studies showed that the joints worked under the mixed-boundary lubrication regime. The low wear produced by these joints showed that this novel joint couple offers low wear rates and therefore may be an alternative material choice for the reduction of osteolysis.

Compliant layer bearings in artificial joints. Part 1: the effects of different manufacturing techniques on the interface strength between an elastomeric layer and a rigid substrate.

The premise that elastomeric materials could be used as one or more of the articulating components in both hip and knee prostheses was postulated first by Unsworth and co-workers. It was thought that such materials might have the capacity to mimic natural joint behaviour more closely than the more rigid bearing surfaces commonly in use. A more natural joint function in artificial joints should promote better tribology, with full fluid-film lubrication being the goal. Early tests showed that this objective could potentially be achieved with a judicious choice of materials and carefully controlled manufacturing techniques. This paper (Part 1 of a two-part series) describes and explains the techniques used to verify the material selection as well as to determine the most appropriate manufacturing procedure to obtain a strong and robust interface between the support and bearing material of the prosthesis. Two polycarbonate urethane (PU) materials with different hardness values (Corethane 80A and Corethane 75D) gave sufficient interfacial strength when moulded under optimum conditions. Corethane 80A was used as the soft bearing material while Corethane 75D provided the rigid backing component. Peel tests revealed strong interface bonds, varying with processing conditions between 350 and 862 N. Fourier transform infrared spectroscopy and micro-thermal analysis showed that a fusion bond over 30 microm thick formed at the interface. The results of the range of tests and analyses, which have been used in this study, have provided sufficient evidence to validate the process used to manufacture these components.

Compliant-layer tibial bearing inserts: friction testing of different materials and designs for a new generation of prostheses that mimic the natural joint.

Total joint replacements (TJRs) have a limited lifetime, but the introduction of devices that exhibit good lubricating properties with low friction and low wear could well extend this. A novel tibial bearing design, using polyurethane (PU) as a compliant layer, to mimic the natural joint, has been developed. To determine accurately the mode of lubrication under which these joints operate, a synthetic lubricant was used in all these tests. Friction tests were carried out to assess the effects of material modulus and surface roughness, together with bearing design parameters such as bearing thickness and conformity, on lubrication. Corethane 80A was the preferred material and was chosen as the compliant layer for subsequent testing. A low surface roughness resulted in lower asperity contact as the asperities were depressed by the pressurized entraining fluid and full-fluid-film lubrication was approached. The three different tibial bearing conformities (low, medium, and high) did not appear to influence the mode of lubrication and all these bearings performed with extremely low friction. Similarly, the bearing thickness effects on lubrication at the levels tested (2 mm, 3 mm, and 4 mm) were minimal, although the effects of layer thickness on interface shear stress could be expected to be significant. This study describes a series of friction tests that have been used to select the most appropriate material and to optimize the design parameters to establish optimum conditions for these compliant layer joints.

Ulcerative vulvitis and balanitis in sheep flocks.

Outbreaks of ulcerative vulvitis and balanitis occurred in three commercial sheep flocks in England and Wales. Between 29 and 44 per cent of the ewes were affected; most of the lesions resolved in three weeks. Pathogens such as mycoplasmas, which have previously been associated with these conditions, were not detected despite using improved laboratory techniques. In one of the flocks, ovine herpesvirus type 2 was detected by pcr in the blood of two acutely affected ewes, from the vulval ulcers of one of them, and from the penis of an affected ram.

Dynapenic Abdominal Obesity Increases Mortality Risk among English and Brazilian Older Adults: A 10-Year Follow-Up of the ELSA and SABE Studies.

BACKGROUND/OBJECTIVE: There is little epidemiological evidence demonstrating that dynapenic abdominal obesity has higher mortality risk than dynapenia and abdominal obesity alone. Our main aim was to investigate whether dynapenia combined with abdominal obesity increases mortality risk among English and Brazilian older adults over ten-year follow-up. DESIGN: Cohort study. SETTING: United Kingdom and Brazil. PARTICIPANTS: Data came from 4,683 individuals from the English Longitudinal Study of Ageing (ELSA) and 1,490 from the Brazilian Health, Well-being and Aging study (SABE), hence the final sample of this study was 6,173 older adults. MEASUREMENTS: The study population was categorized into the following groups: non-dynapenic/non-abdominal obese, abdominal obese, dynapenic, and dynapenic abdominal obese according to their handgrip strength (< 26 kg for men and < 16 kg for women) and waist circumference (> 102 cm for men and > 88 cm for women). The outcome was all-cause mortality over a ten-year follow-up. Adjusted hazard ratios by sociodemographic, behavioural and clinical characteristics were estimated using Cox proportional hazards models. RESULTS: The fully adjusted model showed that dynapenic abdominal obesity has a higher mortality risk among the groups. The hazard ratios (HR) were 1.37 for dynapenic abdominal obesity (95% CI = 1.12 - 1.68), 1.15 for abdominal obesity (95% CI = 0.98 - 1.35), and 1.23 for dynapenia (95% CI = 1.04 - 1.45). CONCLUSIONS: Dynapenia is an important risk factor for mortality but dynapenic abdominal obesity has the highest mortality risk among English and Brazilian older adults.

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.

Polyurethane unicondylar knee prostheses: simulator wear tests and lubrication studies.

Many materials are used as artificial joint bearing surfaces; these include conventional stainless steel or CoCrMo-on-ultra-high molecular weight polyethylene (UHMWPE), CoCrMo on itself and alumina-on-alumina. However, these joints have a limited lifespan resulting in failure of the prosthesis and the need for revision surgery. A number of materials have been introduced recently in an attempt to overcome these problems. Polycarbonate urethane (PU) is a compliant material that can be used as an artificial joint bearing surface which has been developed to mimic the natural synovial joint more accurately by promoting fluid film lubrication. Tribological tests were performed on CoCrMo-on-PU unicondylar knee prostheses to assess their performance in vitro. The wear produced by these components was considerably lower than that found for conventional joints. They also exhibited low friction and operated close to full-fluid film lubrication with viscosities of lubricant similar to those found in patients with arthritis. These tests gave encouraging results for the tribological performance of this material couple for use as an alternative bearing combination.

The wear properties of CFR-PEEK-OPTIMA articulating against ceramic assessed on a multidirectional pin-on-plate machine.

In an attempt to prolong the lives of rubbing implantable devices, several 'new' materials have been examined to determine their suitability as joint couplings. Tests were performed on a multidirectional pin-on-plate machine to determine the wear of both pitch and PAN (polyacrylonitrile)-based carbon fibre reinforced-polyetheretherketone (CFR-PEEK-OPTIMA) pins articulating against both BioLox Delta and BioLox Forte plates (ceramic materials). Both reciprocation and rotational motion were applied to the samples. The tests were conducted using 24.5 per cent bovine serum as the lubricant (protein concentration 15 g/l). Although all four material combinations gave similar low wear with no statistically significant difference (p > 0.25), the lowest average total wear of these pin-on-plate tests was provided by CFR-PEEK-OPTIMA pitch pins versus BioLox Forte plates. This was much lower than the wear produced by conventional joint materials (metal-on-polyethylene) and metal-on-metal combinations when tested on the pin-on-plate machine. This therefore indicates optimism that these PEEK-OPTIMA-based material combinations may perform well in joint applications.

Laboratory studies on the tribology of hard bearing hip prostheses: ceramic on ceramic and metal on metal.

Total hip replacements offer relief to a great many patients every year around the world. With an expected service life of around 25 years on most devices, and with younger and younger patients undergoing this surgery, it is of great importance to understand the mechanisms of their function. Tribological testing of both conventional and hard bearing joint combinations have been conducted in many centres throughout the world, and, after being initially abandoned owing to premature failures, hard bearing combinations have been revisited as viable options for joint replacements. Improved design, manufacturing procedures, and material compositions have led to improved performance over first-generation designs in both metal-on-metal and ceramic-on-ceramic hip prostheses. This paper offers a review of the work conducted in an attempt to highlight the most important factors affecting joint performance and tribology of hard bearing combinations. The tribological performance of these joints is superior to that of conventional metal- or ceramic-on-polymer designs.

A novel astrovirus associated with encephalitis and ganglionitis in domestic sheep.

In June 2013, a 4-year-old Welsh Mountain ewe and in March 2014 a 10-day-old lamb of the same breed and the same flock presented progressive neurological signs including depressed sensorium, tremor, and unusual behaviour. Neuropathological examination of the brain and spinal cord detected non-suppurative polioencephalomyelitis and dorsal root ganglionitis, characteristic of a neurotropic viral agent in both sheep. Metagenomic analysis of different tissue samples from both animals identified a novel Ovine Astrovirus (OvAstV). The presence of viral genome in the central nervous system was confirmed by RT-qPCR. Although the cases presented nine months apart, the identified OvAstV shared nearly identical sequences, differing in only three nucleotide positions across the complete genome. Phylogenetic analysis revealed a close relation of OvAstV to neurotropic bovine astroviruses and an enteric OvAstV. In conclusion, these are the first reported cases of astrovirus infection in domestic sheep that were associated with encephalitis and ganglionitis.

Explant analysis of the Biomet Magnum/ReCap metal-on-metal hip joint.

OBJECTIVES: The high revision rates of the DePuy Articular Surface Replacement (ASR) and the DePuy ASR XL (the total hip arthroplasty (THA) version) have led to questions over the viability of metal-on-metal (MoM) hip joints. Some designs of MoM hip joint do, however, have reasonable mid-term performance when implanted in appropriate patients. Investigations into the reasons for implant failure are important to offer help with the choice of implants and direction for future implant designs. One way to assess the performance of explanted hip prostheses is to measure the wear (in terms of material loss) on the joint surfaces. METHODS: In this study, a coordinate measuring machine (CMM) was used to measure the wear on five failed cementless Biomet Magnum/ReCap/ Taperloc large head MoM THAs, along with one Biomet ReCap resurfacing joint. Surface roughness measurements were also taken. The reason for revision of these implants was pain and/or adverse reaction to metal debris (ARMD) and/or elevated blood metal ion levels. RESULTS: The mean wear rate of the articulating surfaces of the heads and acetabular components of all six joints tested was found to be 6.1 mm3/year (4.1 to 7.6). The mean wear rate of the femoral head tapers of the five THAs was 0.054 mm3/year (0.021 to 0.128) with a mean maximum wear depth of 5.7 µm (4.3 to 8.5). CONCLUSION: Although the taper wear was relatively low, the wear from the articulating surfaces was sufficient to provide concern and was potentially large enough to have been the cause of failure of these joints. The authors believe that patients implanted with the ReCap system, whether the resurfacing prosthesis or the THA, should be closely monitored.Cite this article: S. C. Scholes, B. J. Hunt, V. M. Richardson, D. J. Langton, E. Smith, T. J. Joyce. Explant analysis of the Biomet Magnum/ReCap metal-on-metal hip joint. Bone Joint Res 2017;6:113-122. DOI: 10.1302/2046-3758.62.BJR-2016-0130.R2.

Role of Schmallenberg virus infection in congenital malformations in ruminants in Scotland in 2017.

Scotland's Rural College (SRUC), together with the Moredun Research Institute, carries out surveillance for Schmallenberg virus (SBV) infection in cattle and sheep. This article reports findings relating to diagnoses of fetopathy associated with SBV infection and other congenital malformations in these species made between January 1 and May 5, 2017.