Extradural spinal hydatid cyst causing hindlimb ataxia in a horse.

INTRODUCTION: This case report describes a 13-year-old cob-cross gelding presented for evaluation of recent onset hindlimb ataxia. The gelding had undergone general anaesthesia and tenoscopy of the right hindlimb digital flexor tendon sheath at a nearby clinic three months earlier and had appeared normal at routine post-operative assessments until the sudden onset of neurological deficits. Spinal trauma was suspected initially but radiography and scintigraphy were unremarkable. Due to the severity and progressive nature of the clinical signs the -gelding was subjected to euthanasia. Post mortem examinations (computed tomography, dissection and histopathology) revealed spinal cord compression caused by a single extradural hydatid cyst (Echinococcus equinus), confirmed with PCR, at the level of the 15th thoracic vertebra. This is the first report of a spinal hydatid cyst causing hindlimb ataxia and should therefore be considered a potential differential diagnosis for ataxia in the equine patient.

INTRODUCTION: Ce rapport décrit le cas d'un hongre croisé cob de 13 ans présenté pour l'évaluation d'une ataxie des membres postérieurs d'apparition récente. Le hongre avait subi une anesthésie générale et une ténoscopie de la gaine du tendon du fléchisseur digital du membre postérieur droit dans une clinique voisine trois mois auparavant et avait semblé normal lors des évaluations postopératoires de routine jusqu'à l'apparition soudaine de déficits neurologiques. Un traumatisme rachidien était suspecté au départ, mais la radiographie et la scintigraphie étaient sans particularité. En raison de la gravité et de la nature progressive des signes cliniques, le hongre a été euthanasié. Les examens post mortem (tomodensitométrie, dissection et histopathologie) ont révélé une compression de la moelle épinière provoquée par un unique kyste hydatique extradural (Echinococcus equinus), confirmé par PCR, au niveau de la 15e vertèbre thoracique. Il s'agit du premier cas rapporté d'un kyste hydatique au niveau de la colonne vertébrale causant une ataxie des membres postérieurs et doit donc être considéré comme un diagnostic différentiel potentiel de l'ataxie chez le patient équin.

Secondary compounds from exotic tree plantations change female mating preferences in the palmate newt (Lissotriton helveticus).

Selection can favour phenotypic plasticity in mate choice in response to environmental factors that alter the costs and benefits of being choosy, or of choosing specific mates. Human-induced environmental change could alter sexual selection by affecting the costs of mate choice, or by impairing the ability of individuals to identify preferred mates. For example, variation in mate choice could be driven by environmentally induced differences in body condition (e.g. health) that change the cost of choosiness, or by environmental effects on the ability to detect or discriminate sexual signals. We teased apart these possibilities experimentally, by comparing female mate choice in the palmate newt Lissotriton helveticus between environments that mimic water from either native oak forests or exotic eucalypt plantations. In laboratory two-choice mate trials in clean water, females with prolonged exposure (21 days) to waterborne chemicals leached from eucalypt leaves did not preferentially associate with the male with a stronger immune response, but females exposed to water with chemicals from oak leaves did. In contrast, female choice was unaffected by the immediate presence or absence of eucalypt leachates during mate choice (using only females previously held in oak-treated water). The habitat-related change in female choice we observed is likely to be driven by effects of eucalypt leachates on female physiology, rather than immediate inhibition of pheromone transmission or blocking of pheromone reception.

An ecological role for assortative mating under infection?

Wildlife diseases are emerging at a higher rate than ever before meaning that understanding their potential impacts is essential, especially for those species and populations that may already be of conservation concern. The link between population genetic structure and the resistance of populations to disease is well understood: high genetic diversity allows populations to better cope with environmental changes, including the outbreak of novel diseases. Perhaps following this common wisdom, numerous empirical and theoretical studies have investigated the link between disease and disassortative mating patterns, which can increase genetic diversity. Few however have looked at the possible link between disease and the establishment of assortative mating patterns. Given that assortative mating can reduce genetic variation within a population thus reducing the adaptive potential and long-term viability of populations, we suggest that this link deserves greater attention, particularly in those species already threatened by a lack of genetic diversity. Here, we summarise the potential broad scale genetic implications of assortative mating patterns and outline how infection by pathogens or parasites might bring them about. We include a review of the empirical literature pertaining to disease-induced assortative mating. We also suggest future directions and methodological improvements that could advance our understanding of how the link between disease and mating patterns influences genetic variation and long-term population viability.

Do female Nicrophorus vespilloides reduce direct costs by choosing males that mate less frequently?

Sexual conflict occurs when selection to maximize fitness in one sex does so at the expense of the other sex. In the burying beetle Nicrophorus vespilloides, repeated mating provides assurance of paternity at a direct cost to female reproductive productivity. To reduce this cost, females could choose males with low repeated mating rates or smaller, servile males. We tested this by offering females a dichotomous choice between males from lines selected for high or low mating rate. Each female was then allocated her preferred or non-preferred male to breed. Females showed no preference for males based on whether they came from lines selected for high or low mating rates. Pairs containing males from high mating rate lines copulated more often than those with low line males but there was a negative relationship between female size and number of times she mated with a non-preferred male. When females bred with their preferred male the number of offspring reared increased with female size but there was no such increase when breeding with non-preferred males. Females thus benefited from being choosy, but this was not directly attributable to avoidance of costly male repeated mating.

Post-traumatic stress disorder and alcohol misuse: comorbidity in UK military personnel.

AIMS: To determine the prevalence of comorbid probable post-traumatic stress disorder and alcohol misuse in a UK military cohort study and to determine the level of co-occurrence between these disorders; further aims were to investigate the association between alcohol misuse and the different PTSD symptom clusters, and to assess what factors are associated with probable PTSD in participants with alcohol misuse. METHODS: Data from 9984 participants of Phase 2 of the health and well-being survey of serving and ex-serving members of the UK Armed Forces were assessed for probable PTSD and alcohol misuse using the PTSD checklist (PCL-C) and the alcohol use disorders identification test (AUDIT), respectively. RESULTS: 1.8 % [95 % confidence interval (CI) 1.5-2.1] of the sample met the criteria for both PTSD and alcohol misuse. All three symptom clusters of PTSD were significantly associated with alcohol misuse, with similar odds ranging from 2.46 to 2.85. Factors associated with probable PTSD in individuals reporting alcohol misuse were age [ages 30-34 (years): OR 2.51, 95 % CI 1.15-5.49; ages 40-44 years: OR 2.77, 95 % CI 1.18-6.47], officer rank (OR 0.36, 95 % CI 0.16-0.85), being in a combat role in parent unit (OR 1.99, 95 % CI 1.20-3.31) and common mental disorder (CMD) (OR 21.56, 95 % CI 12.00-38.74). CONCLUSIONS: This study provides strong evidence that PTSD and alcohol misuse are often co-occurring. CMD was highly associated with probable PTSD in individuals with alcohol misuse.

Systematic analysis of funding awarded for viral hepatitis-related research to institutions in the United Kingdom, 1997-2010.

Viral hepatitis is responsible for great health, social and economic burden both globally and in the UK. This study aimed to assess the research funding awarded to UK institutions for viral hepatitis research and the relationship of funded research to clinical and public health burden of viral hepatitis. Databases and websites were systematically searched for information on infectious disease research studies funded for the period 1997-2010. Studies specifically related to viral hepatitis research were identified and categorized in terms of funding by pathogen, disease and by a research and development value chain describing the type of science. The overall data set included 6165 studies (total investment £2.6 billion) of which £76.9 million (3.0%) was directed towards viral hepatitis across 323 studies (5.2%). By pathogen, there were four studies specifically investigating hepatitis A (£3.8 million), 69 studies for hepatitis B (21.4%) with total investment of £14.7 million (19.1%) and 236 (73.1%) hepatitis C studies (£62.7 million, 81.5%). There were 4 studies investigating hepatitis G, and none specifying hepatitis D or E. By associated area, viral hepatitis and therapeutics research received £17.0 million, vaccinology £3.1 million and diagnostics £2.9 million. Preclinical research received £50.3 million (65.4%) across 173 studies, whilst implementation and operational research received £19.4 million (25.3%) across 128 studies. The UK is engaged in much hepatology research, but there are areas where the burden is great and may require greater focus, such as hepatitis E, development of a vaccine for hepatitis C, and further research into hepatitis-associated cancers. Private sector data, and funding information from other countries, would also be useful in priority setting.

Male body size and condition affects sperm number and production rates in mosquitofish, Gambusia holbrooki.

Sperm number is an important predictor of paternity when there is sperm competition. Sperm number is often measured as maximum sperm reserves, but in species where mating is frequent, males will often be replenishing their reserves. Thus, variation in how quickly males can produce sperm is likely to be important in determining male success in sperm competition. Despite this, little is known about how male size, body condition or diet affects sperm production rates. We counted sperm number in large and small Gambusia holbrooki (eastern mosquitofish) after 3 weeks on either a high or low food diet. Sperm number was significantly higher in both larger males and in well-fed males. We then stripped ejaculates again either 1, 2, 3, 4 or 5 days later to investigate subsequent sperm production. The rate of sperm replenishment was influenced by an interaction between size and diet. Large, well-fed males had consistently high levels of sperm available over the 5 days (i.e. rapid replenishment), whereas small poorly fed males showed consistently low levels of sperm availability over the 5 days (i.e. slow replenishment). In contrast, large, poorly fed and small, well-fed males increased their sperm numbers over the first 3 days (i.e. intermediate replenishment). Our study highlights that when mating is frequent and sperm competition is high, size and condition dependence of maximal sperm number and of sperm production rate might both contribute to variation in male reproductive success.

Causes of male sexual trait divergence in introduced populations of guppies.

Males from different populations of the same species often differ in their sexually selected traits. Variation in sexually selected traits can be attributed to sexual selection if phenotypic divergence matches the direction of sexual selection gradients among populations. However, phenotypic divergence of sexually selected traits may also be influenced by other factors, such as natural selection and genetic constraints. Here, we document differences in male sexual traits among six introduced Australian populations of guppies and untangle the forces driving divergence in these sexually selected traits. Using an experimental approach, we found that male size, area of orange coloration, number of sperm per ejaculate and linear sexual selection gradients for male traits differed among populations. Within populations, a large mismatch between the direction of selection and male traits suggests that constraints may be important in preventing male traits from evolving in the direction of selection. Among populations, however, variation in sexual selection explained more than half of the differences in trait variation, suggesting that, despite within-population constraints, sexual selection has contributed to population divergence of male traits. Differences in sexual traits were also associated with predation risk and neutral genetic distance. Our study highlights the importance of sexual selection in trait divergence in introduced populations, despite the presence of constraining factors such as predation risk and evolutionary history.

Sequential mate choice and sexual isolation in threespine stickleback species.

Sequential mate choice strategies predict how females should alter their choosiness based on the availability of attractive males. There are many studies on sequential mate choice within species, but few have asked whether females apply these strategies to interactions between species and how these strategies may affect hybridization. We tested how previous interactions with conspecific and heterospecific males affect mate preference and sexual isolation in two threespine stickleback species (benthics and limnetics: Gasterosteus spp.). Consistent with previous work, we found that within species, stickleback females gauge male attractiveness relative to previously encountered males. If females extend these decision rules between species, we predicted that previous interactions with conspecifics should make heterospecifics less attractive, whereas interactions with heterospecifics should make conspecifics more attractive. However, females found heterospecifics less attractive after prior experience, largely independent of the species of male first encountered. Thus, sequential mate choice strategies are used within but not between species in sticklebacks. Further, learning from prior courtship interactions acts to enhance existing sexual isolation between species.

Allocation of funding into blast injury-related research and blast traumatic brain injury between 2000 and 2019: analysis of global investments from public and philanthropic funders.

INTRODUCTION: There is little systematic tracking or detailed analysis of investments in research and development for blast injury to support decision-making around research future funding. METHODS: This study examined global investments into blast injury-related research from public and philanthropic funders across 2000-2019. Research databases were searched using keywords, and open data were extracted from funder websites. Data collected included study title, abstract, award amount, funder and year. Individual awards were categorised to compare amounts invested into different blast injuries, the scientific approaches taken and analysis of research investment into blast traumatic brain injury (TBI). RESULTS: A total of 806 awards were identified into blast injury-related research globally, equating to US$902.1 million (m, £565.9m GBP). There was a general increase in year-on-year investment between 2003 and 2009 followed by a consistent decline in annual funding since 2010. Pre-clinical research received $671.3 m (74.4%) of investment. Brain-related injury research received $427.7 m (47.4%), orthopaedic injury $138.6 m (15.4%), eye injury $63.7 m (7.0%) and ear injury $60.5m (6.7%). Blast TBI research received a total investment of $384.3 m, representing 42.6% of all blast injury-related research. The U.S. Department of Defense funded $719.3 m (80%). CONCLUSIONS: Investment data suggest that blast TBI research has received greater funding than other blast injury health areas. The funding pattern observed can be seen as reactive, driven by the response to the War on Terror, the rising profile of blast TBI and congressionally mandated research.

Examining confidence and hesitancy towards COVID-19 vaccines: A cross-sectional survey using in-person data collection in rural Ghana.

BACKGROUND: In Ghana, as of 30 July 2022, around one-third of the eligible population are considered fully-vaccinated against COVID-19, and efforts are being made to increase coverage. Vaccine hesitancy is defined by the World Health Organization (WHO) as the delay in the acceptance, or blunt refusal of, vaccines. This study assesses vaccine hesitancy and confidence in Nkwanta South, a rural municipal in Oti region, Ghana. METHODS: Data collection within Nkwanta South took place in sub-municipalities of Alokpatsa (11,028 population), Brewaniase (14,483), and Tutukpene (15,453). Data was collected by 47 local residents, known as Community-Based Surveillance Volunteers (CBSVs), using Kobo Toolbox forms on electronic devices (tablets). Information collected included numerous demographic variables, including age, gender, relationship status, and religion. Further questions covered reasons for vaccine hesitancy and COVID-19 vaccine status. Descriptive and inferential statistics assessed the association between variables to identify predictors of hesitancy. FINDINGS: Across 1500 respondents, 700 (46.7%) reported having received at least one COVID-19 vaccine dose, and 800 (53.3%) reported being unvaccinated against COVID-19. Among unvaccinated respondents, 556 (69.4%) reported willingness to receive the vaccine once available, 190 (23.7%) said they would not be willing to be vaccinated, and 55 (6.9%) said they were unsure. Overall, this represented 30.6% hesitancy within the currently-unvaccinated group. Common reasons for hesitancy included believing that they did not need the vaccine (33.8%), believing the vaccine to be dangerous (30.6%), concerns about side effects (25.3%), and not having enough information (20.1%). Key predictors of hesitancy among our participants included high levels of mistrust, being female, greater years of education, and being Christian. INTERPRETATION: The information gathered here can inform how best to target national and local health promotion strategies. Locally-tailored efforts, that understand local context and social dynamics, must remain a core component of public health activity to achieve a high vaccine uptake.

Indigenous peoples and local communities as partners in the sequencing of global eukaryotic biodiversity.

The aim to sequence, catalog, and characterize the genomes of all of Earth's eukaryotic biodiversity is the shared mission of many ongoing large-scale biodiversity genomics initiatives. Reference genomes of global flora and fauna have the potential to inform a broad range of major issues facing both biodiversity and humanity, such as the impact of climate change, the conservation of endangered species and ecosystems, public health crises, and the preservation and enhancement of ecosystem services. Biodiversity is dramatically declining: 28% of species being assessed by the IUCN are threatened with extinction, and recent reports suggest that a transformative change is needed to conserve and protect what remains. To provide a collective and global genomic response to the biodiversity crisis, many biodiversity genomics initiatives have come together, creating a network of networks under the Earth BioGenome Project. This network seeks to expedite the creation of an openly available, "public good" encyclopedia of high-quality eukaryotic reference genomes, in the hope that by advancing our basic understanding of nature, it can lead to the transformational scientific developments needed to conserve and protect global biodiversity. Key to completing this ambitious encyclopedia of reference genomes, is the ability to responsibly, ethically, legally, and equitably access and use samples from all of the eukaryotic species across the planet, including those that are under the custodianship of Indigenous Peoples and Local Communities. Here, the biodiversity genomics community is subject to the provisions codified in international, national, and local legislations and customary community norms, principles, and protocols. We propose a framework to support biodiversity genomic researchers, projects, and initiatives in building trustworthy and sustainable partnerships with communities, providing minimum recommendations on how to access, utilize, preserve, handle, share, analyze, and communicate samples, genomics data, and associated Traditional Knowledge obtained from, and in partnership with, Indigenous Peoples and Local Communities across the data-lifecycle.

Review: Creutzfeldt-Jakob disease: prion protein type, disease phenotype and agent strain.

The human transmissible spongiform encephalopathies or human prion diseases are one of the most intensively investigated groups of rare human neurodegenerative conditions. They are generally held to be unique in terms of their complex epidemiology and phenotypic variability, but they may also serve as a paradigm with which other more common protein misfolding disorders might be compared and contrasted. The clinico-pathological phenotype of human prion diseases appears to depend on a complex interaction between the prion protein genotype of the affected individual and the physico-chemical properties of the neurotoxic and transmissible agent, thought to comprise of misfolded prion protein. A major focus of research in recent years has been to define the phenotypic heterogeneity of the recognized human prion diseases, correlate this with molecular-genetic features and then determine whether this molecular-genetic classification of human prion disease defines the biological properties of the agent as determined by animal transmission studies. This review seeks to survey the field as it currently stands, summarize what has been learned, and explore what remains to be investigated in order to obtain a more complete scientific understanding of prion diseases and to protect public health.

RNA integrity in post mortem human variant Creutzfeldt-Jakob disease (vCJD) and control brain tissue.

AIMS: To determine premortem and post mortem factors affecting quality and yield of RNA isolated from the unique archived brain material in the UK National Creutzfeldt-Jakob Disease Surveillance Unit Brain and Tissue Bank and to compare this to control brain tissue with no neurological disease. METHODS: In parallel and in replicate, RNA was prepared from the frontal parasagittal or subfrontal cortex of samples dissected from half brains (frozen intact) or from brain samples snap frozen or placed in RNALater. A total of 350 RNA samples from 78 human autopsy cases, 21 variant Creutzfeldt-Jakob disease, 26 other neurological diseases and 31 non-neurological diseases were studied. RESULTS: There was no difference in the quality or yield of RNA isolated from variant Creutzfeldt-Jakob disease, other neurological disease and non-neurological disease brains. RNA preparations from archived frozen half brains or snap frozen autopsy samples were generally of poor quality (RNA integrity number<5). There was a highly significant negative correlation between the number of times frozen half brains had been sampled and the quality of RNA. Samples stored in RNALater provided higher-quality RNA (RNA integrity number>5). Age at death, gender, post mortem interval and freezer storage time had no effect on RNA quality. CONCLUSION: Reasonable-quality RNA can be isolated from samples dissected from archived frozen human half brains but repeated sampling results in RNA degradation. Better-quality RNA is obtained from samples placed in RNALater than from snap frozen samples. The quality and yield of RNA are not affected by age at death, gender, post mortem interval of >6 h or freezer storage time.

The first case of protease-sensitive prionopathy (PSPr) in The Netherlands: a patient with an unusual GSS-like clinical phenotype.

An atypical case of prion disease is described in a 54-year-old Dutch man, homozygous for valine at codon 129 of the prion protein gene (PRNP). The clinical phenotype was characterised by progressive dementia, spastic paraplegia and sensorimotor polyneuropathy. The disease duration was 20 months. Genetic analysis of PRNP did not reveal any abnormalities. Neuropathologically, only mild spongiform change and a coarse granular immunohistochemical staining for the abnormal prion protein, PrP(Sc), was observed, with poorly formed plaques in the molecular layer of the cerebellar cortex. However, Western blotting showed low but detectable levels of proteinase K(PK)-resistant PrP(Sc) occurring in an unusual ladder-like profile. These features define a phenotype that corresponds to the recently described protease-sensitive prionopathy (PSPr). Our report on the first Dutch patient with PSPr further expands the spectrum of prionopathies and exemplifies the need to re-evaluate cases of atypical prion disease.

Variant CJD infection in the spleen of a neurologically asymptomatic UK adult patient with haemophilia.

SUMMARY: All UK patients with bleeding disorders treated with any UK-sourced pooled factor concentrates between 1980 and 2001 have been informed that they may be at an increased risk of infection with variant Creutzfeldt-Jakob disease (vCJD). We describe a study to detect disease-associated, protease-resistant prion protein (PrP(res)) in 17 neurologically aymptomatic patients with haemophilia considered to be at increased risk of vCJD. Materials from 11 autopsy and seven biopsy cases were analysed for PrP(res). The tissues available from each case were variable, ranging from a single biopsy sample to a wide range of autopsy tissues. A single specimen from the spleen of one autopsy case gave a strong positive result on repeated testing for PrP(res) by Western blot analysis. This tissue came from a 73-year-old male patient with no history of neurological disease, who was heterozygous (methionine/valine) at codon 129 in the prion protein gene. He had received over 9000 units of factor VIII concentrate prepared from plasma pools known to include donations from a vCJD-infected donor, and some 400,000 units not known to include donations from vCJD-infected donors. He had also received 14 units of red blood cells and had undergone several surgical and invasive endoscopic procedures. Estimates of the relative risks of exposure through diet, surgery, endoscopy, blood transfusion and receipt of UK-sourced plasma products suggest that by far the most likely route of infection in this patient was receipt of UK plasma products.

Standing magnetic resonance imaging detection of bone marrow oedema-type signal pattern associated with subcarpal pain in 8 racehorses: a prospective study.

REASON FOR PERFORMING STUDY: The proximal metacarpal region is a common site of origin of lameness in the performance horse. A number of disease entities are recognised as causes of proximal metacarpal lameness but a definitive diagnosis is often elusive. Magnetic resonance imaging (MRI) is hypothesised to offer advantages over traditional imaging modalities in the investigation of proximal metacarpal pain. OBJECTIVE: To describe clinical and imaging features of cases of lameness in racehorses arising from the proximal metacarpal region in which standing MRI identified 'bone marrow oedema-type' (BMO-type) signal patterns. METHODS: Records for all horses undergoing standing MRI of the proximal metacarpus/distal carpus from September 2006 to December 2008 were reviewed. Cases underwent a standardised protocol for diagnostic analgesia, radiography and ultrasonography of the proximal metacarpus and distal carpus. Cases with proximal metacarpal lameness displaying a characteristic BMO-type signal pattern on MRI were identified and outcomes analysed. RESULTS: Eight cases were identified with characteristic MRI findings of extensive hyperintensity on T2* gradient echo and short tau inversion fast spin echo sequences and corresponding hypointensity on T1 gradient echo images within the palmaroproximal aspect of the third metacarpal bone. Follow-up information was available for all cases; at the time of writing 7/8 had returned to full work and were free from lameness. CONCLUSIONS: The BMO-type signal patterns visible on MR images in these cases may signal the existence of a previously under-diagnosed pathological process associated with proximal metacarpal lameness in racehorses. This finding is postulated to be associated with a stress reaction and possible prodromal stress fracture of the palmaroproximal metacarpus not appreciable radiographically or ultrasonographically. POTENTIAL RELEVANCE: MRI of the proximal metacarpal region permits detection of pathological processes, which may elude conventional imaging and, therefore, has important therapeutic and prognostic implications in these cases.

Panencephalopathic Creutzfeldt-Jakob disease in the Netherlands and the UK: clinical and pathological characteristics of nine patients.

AIMS: The panencephalopathic type of Creutzfeldt-Jakob disease (PECJD) has extensive abnormalities in cerebral white matter as well as the cortex. PECJD has rarely been described in Caucasians and debate continues on its classification and pathogenesis. We describe our experience of PECJD over a 14-year period of surveillance for CJD in the Netherlands and the UK. METHODS: Between 1993 and 2006, nine cases of PECJD were identified. Clinical, histological and biochemical characteristics of all patients were analysed and compared; all cases were classified clinically as sporadic CJD. RESULTS: The median age at onset was 57.8 years and median disease duration was 22 months. The average brain weight was 887 g. Most patients showed a two-stage clinical course with initial rapid deterioration to a state of akinetic mutism, which then persisted over a longer time scale. Neuropathological findings were characterized by severe global atrophy with status spongiosus. Cerebral white matter involvement tended to be associated with either disease duration or severity of cerebral cortical lesions. Five patients could be classified into the MM1 subtype of sporadic CJD, one patient into the MM2 subgroup and another into the MV2 subgroup. Two patients were heterozygous at codon 129 in the prion protein gene and contained both type 1 and type 2 PrP(res) isoforms in the brain. CONCLUSIONS: We believe that white matter pathology in PECJD represents an end-stage pattern that reflects secondary degeneration due to widespread cortical neuronal loss that occurs in the early part of the disease, rather than representing a primary lesion.