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The effects of corticosteroid drugs on the visual function of zebrafish
No full textPharmacology 2017, London, United Kingdom, 11-13 December 2017Introduction: Glaucoma, a leading cause of blindness, is a heterogenous eye condition characterized by gradual loss of visual acuity due to degeneration of retinal ganglion cells (1). Glaucoma is an off-target effect of corticosteroids when administered intraocularly for treatment of some ocular indications (2). This study uses zebrafish to study whether a glaucoma-type disease is induced by treatment with corticosteroids by assessing the effects on retinal histology and visual function
Cardiovascular Health in Professional Rugby Union Athletes
No full textCardiovascular disease (CVD) defines a class of diseases relating to the heart and
blood vessels, including coronary heart disease, coronary artery disease and
hypertension. CVD risk and outcomes can be managed through modifiable risk
factors, including healthy diet, physical activity, not smoking, normal body weight,
and normal levels of total cholesterol, blood pressure and fasting blood glucose.
Athletes are often regarded as a model of health, through the lifestyle behaviours
associated with elite athleticism. There has been a growing interest in the benefits
and risks associated with high volumes of exercise, with a focus on the relationship
between exercise and cardiovascular health, particularly in sports where increased
body size is common. Rugby athletes often engage in intentional and prolonged
maintenance of elevated body mass, attributable to variances in lean mass and
adipose tissue. The demands required to be successful in rugby lead to adaptations to
cardiovascular physiology, which may expose these athletes to CVD risk. Therefore,
the primary aim of this PhD thesis was to investigate the cardiovascular health of
professional rugby athletes by investigating the prevalence of CVD risk factors and
the implications associated with rugby participation on long-term cardiovascular
health.
This thesis commenced with a systematic review of the cardiovascular health of
retired field-based athletes. Retired athletes with elevated playing time body mass
had an increased prevalence and severity of CVD risk factors, including increased
systolic blood pressure, low-density lipoprotein, cardiometabolic syndrome and
carotid artery calcium. Findings suggested that prior engagement in field-basedsports does not provide long-term protection from CVD. Following this was a
second systematic review of the cardiovascular health of current field-based athletes.
Elevated levels of CVD risk in some athletes, primarily American football athletes
was identified. Lifestyle behaviours associated with elite athleticism, particularly in
athletes with increased body mass, expose athletes to greater metabolic and CVD
risk, which is not completely offset by sport participation. Findings suggest that
athletes who engage in deliberate body mass gain for performance benefits may be
exposed to increased CVD risk.
Study I aimed to assess longitudinal body composition changes in rugby athletes and
to determine if supersizing of athletes was present over a 7- year period. Although
no significant body composition trends were apparent, findings revealed a modest
increase in lean mass and a modest reduction in body fat percentage. While mass is
an integral component to performance in rugby, athletes with increased mass were
found to have a greater propensity to have body fat percentage above desired healthy
ranges.
Study II was designed to investigate visceral fat and changes to visceral fat in
relation to other indices of body composition. No association was identified between
body fat percentage or visceral fat and BMI, rejecting our hypothesis that visceral fat
would display concomitant changes with body fat percentage. Decreases in body fat
percentage did not necessarily reflect changes to visceral fat and reduction may be
caused by subcutaneous fat loss. Moreover, a total mass threshold (116.04 kg) was
identified beyond which lean mass accumulation decreased and body fat percentage
and visceral fat increased.Athlete electrocardiogram (ECG) interpretation is nuanced and normative values
have not been previously established for rugby athletes. Current preparticipation
guidelines from World Rugby endorse but do not mandate the inclusion of an ECG.
Therefore, Study III was designed to examine sport-specific normative ECG values
and evaluate positivity rates using the 2018 international recommendations for ECG
interpretation in athletes. Training-related ECG features were common in rugby
athletes, including incomplete right bundle branch block, sinus bradycardia, sinus
arrhythmia, early repolarisation, increased QRS voltage and first-degree
atrioventricular block. The low positivity rate identified (2.4%) highlights the
importance of clinically effective interpretation of athletes ECGs; understanding
that chronic exposure to high intensity exercise results in several cardiac adaptations
that are reflected on an ECG. Therefore, the prevalence and nature of training-related
features identified in this cohort is similar to normative findings reported in athletes
from other sporting disciplines.
Study IV assesed the prevalence of CVD risk factors in professional rugby athletes.
One fifth of athletes were found to have no cardiovascular risk factors. 74% of
athletes had at least one risk factor: 50% with one- to -two risk factors and 24% with
three- to -four risk factors. The most prevalent risk factors, included elevated Creactive protein, hypertension and dyslipidemia categorised by low high-density
lipoprotein. An increase in body fat percentage and forward position were associated
with a 2.7 and 1.8 increased odds ratio of having a higher number of risk factors,
respectively. Rugby forwards who engage in predominately isometric activity,
demonstrated a level of CVD risk that is comparable to linemen in American
football. Findings indicate that professional rugby athletes are not insusceptible toCVD risk factors, most notably, hypertension, dyslipidemia and elevated C-reactive
protein.
Collectively, the studies in this thesis investigated the overall cardiovascular health
profile of professional rugby athletes by exploring the prevalence of CVD risk
factors and the implications associated with rugby participation on long-term
cardiovascular health. Findings from Study I and Study II may be used to understand
the role of body composition indicies and increasing body mass of rugby athletes. It
is hoped that findings from Study III will be used for the development of normative
values and inform the potential benefits of ECG inclusive screening in rugby
athletes. Study IV findings detail an underestimated and unexpected level of CVD
risk in professional rugby athletes. Further research is required to evaluate the
prognostic impact on cardiovascular health, particular those of larger size
More than just adolescence: differences in fatigue between youth with cerebral palsy and typically developing peers
No full textObjective To quantify differences in fatigue and disordered sleep between adolescents with cerebral palsy (CP)
and their typically developing peers. A secondary aim was to investigate the association between fatigue and
disordered sleep in adolescents with CP.
Methods A convenience sample of 36 youth with CP aged 10–18 years was matched for age and sex with 36
typically developing peers. The Fatigue Impact and Severity Self-Assessment (FISSA), the Patient-Reported
Outcome Measurement Information System (PROMIS) fatigue profile, and the Sleep Disturbance Scale for
Children (SDSC) were collected.
Results Higher fatigue was reported in participants with CP than in their typically developing peers based on
the FISSA total score (mean paired difference=19.06; 99% confidence interval [CI], 6.06–32.1), the FISSA impact
subscale (mean paired difference=11.19; 99% CI, 3.96–18.4), and the FISSA Management and Activity Modification
subscale (mean paired difference=7.86; 99% CI, 1.1–14.6). There were no differences between groups in the
PROMIS fatigue profile (mean paired difference=1.63; 99% CI, -1.57–4.83) or the SDSC total score (mean paired
difference=2.71; 99% CI, -2.93–8.35).
Conclusion Youth with CP experienced significantly more fatigue than their peers as assessed by a comprehensive
measure that considered both general and diagnosis-specific concerns. Sleep did not differ between youth with
CP and their typically developing peers. These findings underscore the need to consider the clinical management
of fatigue across the lifespan of individuals with CP to prevent the associated deterioration of functional abilities
Design of a wearable bruxism detection device
No full textBruxism is a common problem which impacts on between 8 -31% of the general population and presents several symptoms including headaches, facial pain and damage to teeth for sufferers. While gold-standard technologies (e.g. polysomnography) exist and can be used in a clinical context for the diagnosis of bruxism, these are cumbersome and are constrained to laboratory-based testing as a result. In recent years, a number of portable wearable technologies have been developed and evaluated which are based on electromyography, electroencephalography, and/or electrocardiography. In this paper, the development of a novel wearable bruxism detection device based on Inertial Measurement Units (IMU) and a microphone is described as an alternative diagnostic tool for bruxism. The overall system architecture is defined and the implemented hardware platforms are described in detail. Finally, a discussion on the future work is also provided
Sulfur solubility in the Earth magma ocean - Testing the hypothesis of the "Hadean matte"
No full textRhoA regulation by Myo9b and GEF-H1 in platelets
No full textBackground: Circulating platelets are maintained in an inactive state by the endothelial lining of the vasculature. Endothelium-derived prostacyclin and nitric oxide stimulate cAMP- and cGMP-dependent kinases, PKA and PKG, to inhibit platelets. PKA and PKG effects include the inhibition of the GTPase RhoA, which has been suggested to involve the direct phosphorylation of RhoA on serine 188. Objectives: We wanted to confirm RhoA S188 phosphorylation by cyclic nucleotide-dependent kinases and to identify possible alternative mechanisms of RhoA regulation in platelets. Methods: Phosphoproteomics data of human platelets were used to identify candidate PKA and PKG substrates. Phosphorylation of individual proteins was studied by Western blotting and Phos-tag gel electrophoresis in human platelets and transfected HEK293T cells. Pull-down assays were performed to analyze protein interaction and function. Results: Our data indicate that RhoA is not phosphorylated by PKA in platelets. Instead, we provide evidence that cyclic nucleotide effects are mediated through the phosphorylation of the RhoA-specific GTPase-activating protein Myo9b and the guanine nucleotide exchange factor GEF-H1. We identify Myo9b S1354 and guanine nucleotide exchange factor-H1 (GEF-H1) S886 as PKA and PKG phosphorylation sites. Myo9b S1354 phosphorylation enhances its GTPase activating protein function leading to reduced RhoA-GTP levels. GEF-H1 S886 phosphorylation stimulates binding of 14-3-3β and has been shown to inhibit GEF function by facilitating binding of GEF-H1 to microtubules. Microtubule disruption increases RhoA-GTP levels confirming the importance of GEF-H1 in platelets. Conclusion: Phosphorylation of RhoA regulatory proteins Myo9b and GEF-H1, but not RhoA itself, is involved in cyclic nucleotide-mediated control of RhoA in human platelets.University College DublinRussian Foundation For Basic ResearchDeutsche Forschungsgemeinschaf
InSDN: A Novel SDN Intrusion Dataset
No full textSoftware-Defined Network (SDN) has been developed to reduce network complexity through control and manage the whole network from a centralized location. Today, SDN is widely implemented in many data center’s network environments. Nevertheless, emerging technology itself can lead to many vulnerabilities and threats which are still challenging for manufacturers to address it. Therefore, deploying Intrusion Detection Systems (IDSs) to monitor malicious activities is a crucial part of the network architecture. Although the centralized view of the SDN network creates new opportunities for the implementation of IDSs, the performance of these detection techniques relies on the quality of the training datasets. Unfortunately, there are no publicly available datasets that can be used directly for anomaly detection systems applied in SDN networks. The majority of the published studies use non-compatible and outdated datasets, such as the KDD’99 dataset. This manuscript aims to generate an attack-specific SDN dataset and it is publicly available to the researchers. To the best of our knowledge, our work is one of the first solutions to produce a comprehensive SDN dataset to verify the performance of intrusion detection systems. The new dataset includes the benign and various attack categories that can occur in the different elements of the SDN platform. Further, we demonstrate the use of our proposed dataset by performing an experimental evaluation using eight popular machine-learning-based techniques for IDSs
Motion artifact resistant mounting of acoustic emission sensors for knee joint monitoring
No full textAmong the many diverse methods of recording biological signals, sound and acoustic emission monitoring are becoming popular for data acquisition; however, these sensors tend to be very susceptible to motion artefacts and noise. In the case of joint monitoring, this issue is even more significant, considering that joint sounds are recorded during limb movements to establish joint health and performance. This paper investigates different sensor attachment methods for acoustic emission monitoring of the knee, which could lead to reduced motion and skin movement artefacts and improve the quality of sensory data sets. As a proof-of-concept study, several methods were tested over a range of exercises to evaluate noise resistance and signal quality. The signals least affected by motion artefacts were recorded when using high-density ethylene-vinyl acetate (EVA) foam holders, attached to the skin with double-sided biocompatible adhesive tape. Securing and isolating the connecting cable with foam is also recommended to avoid noise due to the cable movement. Clinical Relevance— The results of this study will be useful in joint AE monitoring, as well as in other methods of body sound recording that involve the mounting of relatively heavy sensors, such as phonocardiography and respiratory monitoring
Effects of cold plasma on wheat grain microbiome and antimicrobial efficacy against challenge pathogens and their resistance
No full textThe safety and quality of cereal grain supplies are adversely impacted by microbiological contamination, with novel interventions required to maximise whole grains safety and stability. The microbiological contaminants of wheat grains and the efficacy of Atmospheric Cold Plasma (ACP) for potential to control these risks were investigated. The evaluations were performed using a contained reactor dielectric barrier discharge (DBD) system; samples were treated for 0–20 min using direct and indirect plasma exposure. Amplicon-based metagenomic analysis using bacterial 16S rRNA gene and fungal 18S rRNA gene with internal transcribed spacer (ITS) region was performed to characterize the change in microbial community composition in response to ACP treatment. The antimicrobial efficacy of ACP against a range of bacterial and fungal contaminants of wheat, was assessed to include individual isolates from grains as challenge pathogens. ACP influenced wheat microbiome composition, with a higher microbial diversity as well as abundance found on the untreated control grain samples. Culture and genomic approaches revealed different trends for mycoflora detection and control. A challenge study demonstrated that using direct mode of plasma exposure with 20 min of treatment significantly reduced the concentration of all pathogens. Overall, reduction levels for B. atrophaeus vegetative cells were higher than for all fungal species tested, whereas B. atrophaeus spores were the most resistant to ACP among all microorganisms tested. Of note, repeating sub-lethal plasma treatment did not induce resistance to ACP in either B. atrophaeus or A. flavus spores. ACP process control could be tailored to address diverse microbiological risks for grain stability and safety.Science Foundation Irelan
High voltage atmospheric cold air plasma control of bacterial biofilms on fresh produce
No full textAtmospheric cold plasma (ACP) offers great potential for decontamination of food borne pathogens. This study examined the antimicrobial efficacy of ACP against a range of pathogens of concern to fresh produce comparing planktonic cultures, monoculture biofilms (Escherichia coli, Salmonella enterica, Listeria monocytogenes, Pseudomonas fluorescens) and mixed culture biofilms (Listeria monocytogenes and Pseudomonas fluorescens). Biotic and abiotic surfaces commonly occurring in the fresh food industry were investigated. Microorganisms showed varying susceptibility to ACP treatment depending on target and process factors. Bacterial biofilm populations treated with high voltage (80 kV) ACP were reduced significantly (p < 0.05) in both mono- and mixed species biofilms after 60 s of treatment and yielded non-detectable levels after extending treatment time to 120 s. However, an extended time was required to reduce the challenge mixed culture biofilm of L. monocytogenes and P. fluorescens inoculated on lettuce, which was dependent on biofilm formation conditions and substrate. Contained treatment for 120 s reduced L. monocytogenes and P. fluorescens inoculated as mixed cultures on lettuce (p < 0.05) by 2.2 and 4.2 Log 10 CFU/ml respectively. When biofilms were grown at 4 °C on lettuce, there was an increased resistance to ACP treatment by comparison with biofilm grown at temperature abuse conditions of 15 °C. Similarly, L. monocytogenes and P. fluorescens exposed to cold stress (4 °C) for 1 h demonstrated increased tolerance to ACP treatment compared to non-stressed cells. These finding demonstrates that bacterial form, mono versus mixed challenges as well as environmental stress conditions play an important role in ACP inactivation efficacy.Department of Agriculture, Food and the MarineScience Foundation IrelandBiotechnology and Biological Sciences Research Counci