237 research outputs found
Electron Bio-Imaging Centre (eBIC): the UK national research facility for biological electron microscopy
The recent resolution revolution in cryo-EM has led to a massive increase in demand for both time on high-end cryo-electron microscopes and access to cryo-electron microscopy expertise. In anticipation of this demand, eBIC was set up at Diamond Light Source in collaboration with Birkbeck College London and the University of Oxford, and funded by the Wellcome Trust, the UK Medical Research Council (MRC) and the Biotechnology and Biological Sciences Research Council (BBSRC) to provide access to high-end equipment through peer review. eBIC is currently in its start-up phase and began by offering time on a single FEI Titan Krios microscope equipped with the latest generation of direct electron detectors from two manufacturers. Here, the current status and modes of access for potential users of eBIC are outlined. In the first year of operation, 222 d of microscope time were delivered to external research groups, with 95 visits in total, of which 53 were from unique groups. The data collected have generated multiple high- to intermediate-resolution structures (2.8–8 Å), ten of which have been published. A second Krios microscope is now in operation, with two more due to come online in 2017. In the next phase of growth of eBIC, in addition to more microscope time, new data-collection strategies and sample-preparation techniques will be made available to external user groups. Finally, all raw data are archived, and a metadata catalogue and automated pipelines for data analysis are being developed
Mortality in East African shorthorn zebu cattle under one year : predictors of infectious-disease mortality
BACKGROUND: Infectious livestock diseases remain a major threat to attaining food security and are a source of
economic and livelihood losses for people dependent on livestock for their livelihood. Knowledge of the vital
infectious diseases that account for the majority of deaths is crucial in determining disease control strategies and in
the allocation of limited funds available for disease control. Here we have estimated the mortality rates in zebu
cattle raised in a smallholder mixed farming system during their first year of life, identified the periods of increased
risk of death and the risk factors for calf mortality, and through analysis of post-mortem data, determined the
aetiologies of calf mortality in this population. A longitudinal cohort study of 548 zebu cattle was conducted
between 2007 and 2010. Each calf was followed during its first year of life or until lost from the study. Calves were
randomly selected from 20 sub-locations and recruited within a week of birth from different farms over a 45 km
radius area centered on Busia in the Western part of Kenya. The data comprised of 481.1 calf years of observation.
Clinical examinations, sample collection and analysis were carried out at 5 week intervals, from birth until one year
old. Cox proportional hazard models with frailty terms were used for the statistical analysis of risk factors. A
standardized post-mortem examination was conducted on all animals that died during the study and appropriate
samples collected.
RESULTS: The all-cause mortality rate was estimated at 16.1 (13.0-19.2; 95% CI) per 100 calf years at risk. The Cox
models identified high infection intensity with Theileria spp., the most lethal of which causes East Coast Fever
disease, infection with Trypanosome spp., and helminth infections as measured by Strongyle spp. eggs per gram of
faeces as the three important infections statistically associated with infectious disease mortality in these calves.
Analysis of post-mortem data identified East Coast Fever as the main cause of death accounting for 40% of all
deaths, haemonchosis 12% and heartwater disease 7%. CONCLUSION: The findings demonstrate the impact of endemic parasitic diseases in indigenous animals expected to
be well adapted against disease pressures. Additionally, agreement between results of Cox models using data from
simple diagnostic procedures and results from post-mortem analysis underline the potential use such diagnostic
data to reduce calf mortality. The control strategies for the identified infectious diseases have been discussed.The Wellcome Trust (grant No. 079,445)http://www.biomedcentral.com/1746-6148/9/175am2013ab201
Parasite co-infections show synergistic and antagonistic interactions on growth performance of East African zebu cattle under one year
The co-occurrence of different pathogen species and their simultaneous infection of hosts are common, and may affect host
health outcomes. Co-infecting pathogens may interact synergistically (harming the host more) or antagonistically (harming
the host less) compared with single infections. Here we have tested associations of infections and their co-infections with
variation in growth rate using a subset of 455 animals of the Infectious Diseases of East Africa Livestock (IDEAL) cohort
study surviving to one year. Data on live body weight, infections with helminth parasites and haemoparasites were collected
every 5 weeks during the first year of life. Growth of zebu cattle during the first year of life was best described by a linear
growth function. A large variation in daily weight gain with a range of 0·03–0·34 kg, and a mean of 0·135 kg (0·124, 0·146;
95% CI) was observed. After controlling for other significant covariates in mixed effects statistical models, the results
revealed synergistic interactions (lower growth rates) with Theileria parva and Anaplasma marginale co-infections, and
antagonistic interactions (relatively higher growth rates) with T. parva and Theileria mutans co-infections, compared with
infections with T. parva only. Additionally, helminth infections can have a strong negative effect on the growth rates but this
is burden-dependent, accounting for up to 30% decrease in growth rate in heavily infected animals. These findings present
evidence of pathogen–pathogen interactions affecting host growth, and we discuss possible mechanisms that may explain
observed directions of interactions as well as possible modifications to disease control strategies when co-infections are
present.This work was supported by the Wellcome Trust (grant
No. 079445).http://www.parasitesandvectors.com/am2014ab201
Parasite co-infections and their impact on survival of indigenous cattle
In natural populations, individuals may be infected with multiple distinct pathogens at a time. These pathogens may act
independently or interact with each other and the host through various mechanisms, with resultant varying outcomes on
host health and survival. To study effects of pathogens and their interactions on host survival, we followed 548 zebu cattle
during their first year of life, determining their infection and clinical status every 5 weeks. Using a combination of clinical
signs observed before death, laboratory diagnostic test results, gross-lesions on post-mortem examination, histo-pathology
results and survival analysis statistical techniques, cause-specific aetiology for each death case were determined, and effect
of co-infections in observed mortality patterns. East Coast fever (ECF) caused by protozoan parasite Theileria parva and
haemonchosis were the most important diseases associated with calf mortality, together accounting for over half (52%) of
all deaths due to infectious diseases. Co-infection with Trypanosoma species increased the hazard for ECF death by 6 times
(1.4–25; 95% CI). In addition, the hazard for ECF death was increased in the presence of Strongyle eggs, and this was burden
dependent. An increase by 1000 Strongyle eggs per gram of faeces count was associated with a 1.5 times (1.4–1.6; 95% CI)
increase in the hazard for ECF mortality. Deaths due to haemonchosis were burden dependent, with a 70% increase in
hazard for death for every increase in strongyle eggs per gram count of 1000. These findings have important implications
for disease control strategies, suggesting a need to consider co-infections in epidemiological studies as opposed to singlepathogen
focus, and benefits of an integrated approach to helminths and East Coast fever disease control.The Wellcome Trust (grant No. 079445)http://www.plosone.orgam201
Hematological profile of East African short-horn zebu calves from birth to 51 weeks of age
This paper is the first attempt to accurately describe the hematological parameters for
any African breed of cattle, by capturing the changes in these parameters over the first
12 months of an animal’s life using a population-based sample of calves reared under
field conditions and natural disease challenge. Using a longitudinal study design, a
stratified clustered random sample of newborn calves was recruited into the IDEAL
study and monitored at 5-weekly intervals until 51 weeks of age. The blood cell analysis performed at each visit included: packed cell volume; red cell count; red cell
distribution width; mean corpuscular volume; mean corpuscular hemoglobin
concentration; hemoglobin concentration; white cell count; absolute lymphocyte,
eosinophil, monocyte, and neutrophil counts; platelet count; mean platelet volume;
and total serum protein. The most significant age-related change in the red cell
parameters was a rise in red cell count and hemoglobin concentration during the
neonatal period. This is in contrast to what is reported for other ruminants, including
European cattle breeds where the neonatal period is marked by a fall in the red cell
parameters. There is a need to establish breed-specific reference ranges for blood
parameters for indigenous cattle breeds. The possible role of the postnatal rise in the
red cell parameters in the adaptability to environmental constraints and innate disease
resistance warrants further research into the dynamics of blood cell parameters of
these breeds.Wellcome Trust (project no.079445).http://link.springer.com/journal/580hb2013ab201
Searches for invisible decays of the Higgs boson in pp collisions at root S=7, 8, and 13 TeV
Peer reviewe
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