A novel antigen capture ELISA for the specific detection of IgG antibodies to elephant endotheliotropic herpes virus

BACKGROUND Elephants are classified as critically endangered animals by the International Union for Conservation of Species (IUCN). Elephant endotheliotropic herpesvirus (EEHV) poses a large threat to breeding programs of captive Asian elephants by causing fatal haemorrhagic disease. EEHV infection is detected by PCR in samples from both clinically ill and asymptomatic elephants with an active infection, whereas latent carriers can be distinguished exclusively via serological assays. To date, identification of latent carriers has been challenging, since there are no serological assays capable of detecting seropositive elephants. RESULTS Here we describe a novel ELISA that specifically detects EEHV antibodies circulating in Asian elephant plasma/serum. Approximately 80 % of PCR positive elephants display EEHV-specific antibodies. Monitoring three Asian elephant herds from European zoos revealed that the serostatus of elephants within a herd varied from non-detectable to high titers. The antibody titers showed typical herpes-like rise-and-fall patterns in time which occur in all seropositive animals in the herd more or less simultaneously. CONCLUSIONS This study shows that the developed ELISA is suitable to detect antibodies specific to EEHV. It allows study of EEHV seroprevalence in Asian elephants. Results confirm that EEHV prevalence among Asian elephants (whether captive-born or wild-caught) is high

The genetic heterogeneity and mutational burden of engineered melanomas in zebrafish models.

BACKGROUND: Melanoma is the most deadly form of skin cancer. Expression of oncogenic BRAF or NRAS, which are frequently mutated in human melanomas, promote the formation of nevi but are not sufficient for tumorigenesis. Even with germline mutated p53, these engineered melanomas present with variable onset and pathology, implicating additional somatic mutations in a multi-hit tumorigenic process. RESULTS: To decipher the genetics of these melanomas, we sequence the protein coding exons of 53 primary melanomas generated from several BRAF(V600E) or NRAS(Q61K) driven transgenic zebrafish lines. We find that engineered zebrafish melanomas show an overall low mutation burden, which has a strong, inverse association with the number of initiating germline drivers. Although tumors reveal distinct mutation spectrums, they show mostly C > T transitions without UV light exposure, and enrichment of mutations in melanogenesis, p53 and MAPK signaling. Importantly, a recurrent amplification occurring with pre-configured drivers BRAF(V600E) and p53-/- suggests a novel path of BRAF cooperativity through the protein kinase A pathway. CONCLUSION: This is the first analysis of a melanoma mutational landscape in the absence of UV light, where tumors manifest with remarkably low mutation burden and high heterogeneity. Genotype specific amplification of protein kinase A in cooperation with BRAF and p53 mutation suggests the involvement of melanogenesis in these tumors. This work is important for defining the spectrum of events in BRAF or NRAS driven melanoma in the absence of UV light, and for informed exploitation of models such as transgenic zebrafish to better understand mechanisms leading to human melanoma formation

Frequency of LATE neuropathologic change across the spectrum of Alzheimer’s disease neuropathology: combined data from 13 community-based or population-based autopsy cohorts

Limbic-predominant age-related TDP-43 encephalopathy neuropathologic change (LATE-NC) and Alzheimer’s disease neuropathologic change (ADNC) are each associated with substantial cognitive impairment in aging populations. However, the prevalence of LATE-NC across the full range of ADNC remains uncertain. To address this knowledge gap, neuropathologic, genetic, and clinical data were compiled from 13 high-quality community- and population-based longitudinal studies. Participants were recruited from United States (8 cohorts, including one focusing on Japanese–American men), United Kingdom (2 cohorts), Brazil, Austria, and Finland. The total number of participants included was 6196, and the average age of death was 88.1 years. Not all data were available on each individual and there were differences between the cohorts in study designs and the amount of missing data. Among those with known cognitive status before death (n = 5665), 43.0% were cognitively normal, 14.9% had MCI, and 42.4% had dementia—broadly consistent with epidemiologic data in this age group. Approximately 99% of participants (n = 6125) had available CERAD neuritic amyloid plaque score data. In this subsample, 39.4% had autopsy-confirmed LATE-NC of any stage. Among brains with “frequent” neuritic amyloid plaques, 54.9% had comorbid LATE-NC, whereas in brains with no detected neuritic amyloid plaques, 27.0% had LATE-NC. Data on LATE-NC stages were available for 3803 participants, of which 25% had LATE-NC stage > 1 (associated with cognitive impairment). In the subset of individuals with Thal Aβ phase = 0 (lacking detectable Aβ plaques), the brains with LATE-NC had relatively more severe primary age-related tauopathy (PART). A total of 3267 participants had available clinical data relevant to frontotemporal dementia (FTD), and none were given the clinical diagnosis of definite FTD nor the pathological diagnosis of frontotemporal lobar degeneration with TDP-43 inclusions (FTLD-TDP). In the 10 cohorts with detailed neurocognitive assessments proximal to death, cognition tended to be worse with LATE-NC across the full spectrum of ADNC severity. This study provided a credible estimate of the current prevalence of LATE-NC in advanced age. LATE-NC was seen in almost 40% of participants and often, but not always, coexisted with Alzheimer’s disease neuropathology

Feasibility of short message service to document bleeding episodes in children with haemophilia

The increasing emphasis on home-based treatment for the management of children with haemophilia has meant that many of these children no longer regularly report to a medical facility. Consequently, it is difficult to monitor incidence of bleeding episodes. The aim of this study was to assess the feasibility of using a short message service (SMS) to monitor incidence of bleeding episodes in children with haemophilia. One hundred and four children with moderate and severe haemophilia A or B took part in a 1-year prospective study between 2008 and 2010. Children or their parents were asked to maintain a bleeds diary. They received a weekly SMS asking whether there had been a bleeding episode in the preceding week. Response rates were calculated. Children were followed for a total of 4839 person-weeks. SMS replies were received for 4201 weeks. Thus, the rate of follow-up was 86.8%. Median responses rates were 94.2% (IQR: 86.1–100%). Weekly SMS is a feasible reporting tool for documenting bleeding episodes in children with haemophilia. It is associated with high response rates and minimal expense and intrusion. The use of SMS could be extended to encourage compliance to prophylactic treatment, particularly in adolescents with haemophilia

Association between physical activity and risk of bleeding in children with hemophilia

Context: Vigorous physical activity is thought to increase risk of bleeds in children with hemophilia, but the magnitude of the risk is unknown. Objective: To quantify the transient increase in risk of bleeds associated with physical activity in children with hemophilia. Design, Setting, and Participants: A case-crossover study nested within a prospective cohort study was conducted at 3 pediatric hemophilia centers in Australia between July 2008 and October 2010. A total of 104 children and adolescent boys aged 4 through 18 years with moderate or severe hemophilia A or B were monitored for bleeds for up to 1 year. Following each bleed, the child or parent was interviewed to ascertain exposures to physical activity preceding the bleed. Physical activity was categorized according to expected frequency and severity of collisions. The risk of bleeds associated with physical activity was estimated by contrasting exposure to physical activity in the 8 hours before the bleed with exposures in two 8-hour control windows, controlling for levels of clotting factor in the blood. Main Outcome Measures: Association of physical activity and factor level with risk of bleeding. Results: The participants were observed for 4839 person-weeks during which time 436 bleeds occurred. Of these, 336 bleeds occurred more than 2 weeks after the preceding bleed and were used in the primary analysis of risk. Compared with inactivity and category 1 activities (eg, swimming), category 2 activities (eg, basketball) were associated with a transient increase in the risk of bleeding (30.6% of bleed windows vs 24.8% of first control windows; odds ratio, 2.7; 95% CI, 1.7-4.8, P < .001). Category 3 activities (eg, wrestling) were associated with a greater transient increase in risk (7.0% of bleed windows vs 3.4% of first control windows; odds ratio, 3.7; 95% CI, 2.3-7.3, P < .001). To illustrate absolute risk increase, for a child who bleeds 5 times annually and is exposed on average to category 2 activities twice weekly and to category 3 activities once weekly, exposure to these activities was associated with only 1 of the 5 annual bleeds. For every 1% increase in clotting factor level, bleeding incidence was lower by 2% (95% CI, 1%-3%; P = .004). Conclusions: In children and adolescents with hemophilia, vigorous physical activity was transiently associated with a moderate relative increase in risk of bleeding. Because the increased relative risk is transient, the absolute increase in risk of bleeds associated with physical activity is likely to be small

Evaluating Montreál's harm reduction interventions for people who inject drugs: protocol for observational study and cost-effectiveness analysis

Introduction The main harm reduction interventions for people who inject drugs (PWID) are supervised injection facilities, needle and syringe programmes and opioid agonist treatment. Current evidence supporting their implementation and operation underestimates their usefulness by excluding skin, soft tissue and vascular infections (SSTVIs) and anoxic/toxicity-related brain injury from cost-effectiveness analyses (CEA). Our goal is to conduct a comprehensive CEA of harm reduction interventions in a setting with a large, dispersed, heterogeneous population of PWID, and include prevention of SSTVIs and anoxic/toxicity-related brain injury as measures of benefit in addition to HIV, hepatitis C and overdose morbidity and mortalities averted. Methods and analysis This protocol describes how we will develop an open, retrospective cohort of adult PWID living in Québec between 1 January 2009 and 31 December 2020 using administrative health record data. By complementing this data with non-linkable paramedic dispatch records, regional monthly needle and syringe dispensation counts and repeated cross-sectional biobehavioural surveys, we will estimate the hazards of occurrence and the impact of Montreál's harm reduction interventions on the incidence of drug-use-related injuries, infections and deaths. We will synthesise results from our empirical analyses with published evidence to simulate infections and injuries in a hypothetical population of PWID in Montreál under different intervention scenarios including current levels of use and scale-up, and assess the cost-effectiveness of each intervention from the public healthcare payer's perspective. Ethics and dissemination This study was approved by McGill University's Institutional Review Board (Study Number: A08-E53-19B). We will work with community partners to disseminate results to the public and scientific community via scientific conferences, a publicly accessible report, op-ed articles and open access peer-reviewed journals