Publications by authors named "MacMahon E"

In some fish lineages, evolution has led to unique sensory adaptations that provide information which is not available to terrestrial animals. These sensory systems include, among others, electroreception, which together with the ability of fish to generate electric discharges plays a role in social communication and object location. Most studies on electric phenomena in aquatic animals are dedicated to selected groups of electric fishes that regularly generate electric signals (Mormyriformes, Gymnotiformes).

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Superparamagnetic iron oxide nanoparticles, MNPs, are under investigation as stimulus-responsive nanocarriers that can be tracked by magnetic resonance imaging. However, fundamental questions remain, including the effect of differing surface chemistries on MR image contrast efficacy (relaxivity), both initially and over time in the biological environment. The effects of pH and ligand type on the relaxivity of electrostatically and sterically stabilized spherical 8.

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There is a worldwide need for reagents to perform SARS-CoV-2 detection. Some laboratories have implemented kit-free protocols, but many others do not have the capacity to develop these and/or perform manual processing. We provide multiple workflows for SARS-CoV-2 nucleic acid detection in clinical samples by comparing several commercially available RNA extraction methods: QIAamp Viral RNA Mini Kit (QIAgen), RNAdvance Blood/Viral (Beckman) and Mag-Bind Viral DNA/RNA 96 Kit (Omega Bio-tek).

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Containing the global severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has been an unprecedented challenge due to high horizontal transmissivity and asymptomatic carriage rates. Lateral flow device (LFD) immunoassays were introduced in late 2020 to detect SARS-CoV-2 infection in asymptomatic or presymptomatic individuals rapidly. While LFD technologies have been used for over 60 years, their widespread use as a public health tool during a pandemic is unprecedented.

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There is a worldwide need for reagents to perform SARS-CoV-2 detection. Some laboratories have implemented kit-free protocols, but many others do not have the capacity to develop these and/or perform manual processing. We provide multiple workflows for SARS-CoV-2 nucleic acid detection in clinical samples by comparing several commercially available RNA extraction methods: QIAamp Viral RNA Mini Kit (QIAgen), RNAdvance Blood/Viral (Beckman) and Mag-Bind Viral DNA/RNA 96 Kit (Omega Bio-tek).

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During the first wave of the global COVID-19 pandemic the clinical utility and indications for SARS-CoV-2 serological testing were not clearly defined. The urgency to deploy serological assays required rapid evaluation of their performance characteristics. We undertook an internal validation of a CE marked lateral flow immunoassay (LFIA) (SureScreen Diagnostics) using serum from SARS-CoV-2 RNA positive individuals and pre-pandemic samples.

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Article Synopsis
  • Antibody responses to SARS-CoV-2 usually appear in most infected individuals within 10-15 days after symptoms start, but it's unclear how long they last or if they protect against reinfection.
  • The study analyzed serum samples from 65 confirmed cases over 94 days and found that over 95% of individuals developed various antibody types, with neutralizing antibodies detected after 8 days post-symptom onset.
  • Results indicated that while some individuals retained high neutralizing antibody levels for more than 60 days, others experienced a significant decline, suggesting that booster vaccinations may be necessary for sustained protection against COVID-19.
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There is a clear requirement for an accurate SARS-CoV-2 antibody test, both as a complement to existing diagnostic capabilities and for determining community seroprevalence. We therefore evaluated the performance of a variety of antibody testing technologies and their potential use as diagnostic tools. Highly specific in-house ELISAs were developed for the detection of anti-spike (S), -receptor binding domain (RBD) and -nucleocapsid (N) antibodies and used for the cross-comparison of ten commercial serological assays-a chemiluminescence-based platform, two ELISAs and seven colloidal gold lateral flow immunoassays (LFIAs)-on an identical panel of 110 SARS-CoV-2-positive samples and 50 pre-pandemic negatives.

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Our knowledge of COVID-19 is changing and evolving rapidly, with novel insights and recommendations, almost on a daily basis. It behooves the medical community to provide updated information on a regular basis, on best practice to facilitate optimal care of infected patients and on appropriate advice for the general population. This is particularly important in the case of patients with chronic conditions, such as inflammatory bowel disease [IBD].

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An evaluation of a rapid portable gold-nanotechnology measuring SARS-CoV-2 IgM, IgA and IgG antibody concentrations against spike 1 (S1), spike 2 (S) and nucleocapsid (N) was conducted using serum samples from 74 patients tested for SARS-CoV-2 RNA on admission to hospital, and 47 historical control patients from March 2019. 59 patients were RNA(+) and 15 were RNA(-). A serum (±) classification was derived for all three antigens and a quantitative serological profile was obtained.

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Crohn's disease (CD) and ulcerative colitis (UC), the 2 main clinical phenotypes of inflammatory bowel disease (IBD), are diseases that result from a dysregulated immune response to gut microbiota in genetically susceptible hosts. This aberrant immune response may intrinsically predispose IBD patients to infectious complications. Moreover, immunosuppressive medications used to treat IBD including corticosteroids, thiopurines, methotrexate, calcineurin inhibitors, anti-tumor necrosis factor (anti-TNF) agents and other biologics, further increase patients' susceptibility to opportunistic infections.

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Unlabelled: Varicella-zoster virus (VZV) is a human herpesvirus, which during primary infection typically causes varicella (chicken pox) and establishes lifelong latency in sensory and autonomic ganglia. Later in life, the virus may reactivate to cause herpes zoster (HZ; also known as shingles). To prevent these diseases, a live-attenuated heterogeneous vaccine preparation, vOka, is used routinely in many countries worldwide.

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Patients with vulval aphthae, also termed Lipschütz ulcers, often present to genitourinary medicine clinics. Typically, these ulcers present as acute, painful, vulval ulcers in young women and adolescents. The aetiology is unknown, and often these ulcers are accompanied by flu-like symptoms.

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Background: It is increasingly recognized that human rhinoviruses (HRV) can be associated with severe infections. However, conflicting results have been reported on the relative prevalence and severity of the three HRV species.

Objectives: The relative prevalence and clinical characteristics of HRV-A, B and C, in children attending a South London teaching hospital were investigated retrospectively.

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Background: Primary BK virus (BKV) infection is probably acquired by the respiratory route in childhood, and latent virus persists principally in the urinary tract. BKV reactivation is implicated in late onset haemorrhagic cystitis (HC) post Haematopoietic Stem Cell Transplant (HSCT). There is emerging evidence that BKV can cause life-threatening pneumonitis in immunocompromised individuals.

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Enterovirus 68 (EV68) was first isolated in 1962. Very few cases of EV68 infection were described over the ensuing 40 years. However, in the past few years, an increase in severe respiratory tract infections associated with EV68 has been reported.

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The European Union Tissues and Cells Directive requires screening of tissue and cell donors for infective organisms to prevent inter-patient transmission. The Directive includes the unique term partner donation, which refers to "donation of reproductive cells between a man and a woman who declare that they have an intimate physical relationship". In line with the Directive, partners undergoing Assisted Reproductive Technology (ART) now require screening before each treatment, regardless of the time interval between consecutive cycles.

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