Publications by authors named "James Mckenna"

Article Synopsis
  • - The study investigates the feasibility of using wastewater-based epidemiology (WBE) and whole-genome sequencing (WGS) to detect and differentiate between human and avian strains of Influenza A viruses (IAVs) across Northern Ireland.
  • - Between August and December 2022, wastewater samples from six treatment facilities revealed a constant presence of IAVs, with varied proportions of human and avian strains, though no strong correlation was found with clinical IAV data from the region.
  • - The findings suggest that WBE can effectively monitor circulating IAV strains, offering a valuable approach for ongoing surveillance and potential prevention of influenza outbreaks through genetic analysis.
View Article and Find Full Text PDF

Aging is a non-modifiable understudied risk factor for hypertension. We hypothesized that sympathetically mediated activation of renal sodium reabsorption drives age-dependent hypertension and the salt sensitivity of blood pressure (BP). Using 3-, 8-, and 16-month-old male and female Sprague-Dawley rats as a model of normal aging, we assessed BP, indices of sympathetic tone, and the physiological responses to acute and chronic sodium challenge including sodium chloride cotransporter (NCC) regulation.

View Article and Find Full Text PDF

Hypertension affects approximately one in two United States adults and sex plays an important role in the pathogenesis of hypertension. The Na-Cl cotransporter (NCC), regulated by a kinase network including with-no-lysine kinase (WNK)1 and WNK4, STE20/SPS1-related proline alanine-rich kinase (SPAK), and oxidative stress response 1 (OxSR1), is critical to Na reabsorption and blood pressure regulation. Dietary salt differentially modulates NCC in salt-sensitive and salt-resistant rats, in part by modulation of WNK/SPAK/OxSR1 signaling.

View Article and Find Full Text PDF
Article Synopsis
  • * Most Npas1 neurons are identified as GABAergic, showing a significantly higher density compared to neighboring neuron types and have extensive projections to brain areas related to sleep, motivation, and olfaction.
  • * Activation of these Npas1 neurons results in increased wakefulness and altered sleep patterns, indicating their potential role in wakefulness regulation and stress-induced insomnia, which may have implications for sleep disorders and neuropsychiatric conditions.
View Article and Find Full Text PDF

Analyzing scored sleep is a fundamental prerequisite to understanding how sleep changes between health and disease. Classically, this is accomplished by manually calculating various measures (e.g.

View Article and Find Full Text PDF

Respiratory syncytial virus (RSV) causes severe infections in infants, immunocompromised or elderly individuals resulting in annual epidemics of respiratory disease. Currently, limited clinical surveillance and the lack of predictable seasonal dynamics limit the public health response. Wastewater-based epidemiology (WBE) has recently been used globally as a key metric in determining prevalence of severe acute respiratory syndrome coronavirus 2 in the community, but its application to other respiratory viruses is limited.

View Article and Find Full Text PDF
Article Synopsis
  • Enterovirus D68 (EV-D68) infections can cause severe respiratory issues and acute flaccid myelitis, with a significant rise reported during the fall-winter season of 2021-2022 across Europe.
  • The study by the European Non-Polio Enterovirus Network (ENPEN) analyzed over 10,481 samples from 19 countries, identifying 1,004 as EV-D68, predominantly affecting young children, where 37.9% required hospitalization.
  • Additionally, genetic analyses uncovered two new B3-derived lineages without regional patterns, indicating a notable impact of the infections and the emergence of new virus strains.
View Article and Find Full Text PDF

Plant defensins are a large family of small cationic proteins with diverse functions and mechanisms of action, most of which assert antifungal activity against a broad spectrum of fungi. The partial mechanism of action has been resolved for a small number of members of plant defensins, and studies have revealed that many act by more than one mechanism. The plant defensin Ppdef1 has a unique sequence and long loop 5 with fungicidal activity against a range of human fungal pathogens, but little is known about its mechanism of action.

View Article and Find Full Text PDF

Onychomycosis, or fungal nail infection, causes not only pain and discomfort but can also have psychological and social consequences for the patient. Treatment of onychomycosis is complicated by the location of the infection under the nail plate, meaning that antifungal molecules must either penetrate the nail or be applied systemically. Currently, available treatments are limited by their poor nail penetration for topical products or their potential toxicity for systemic products.

View Article and Find Full Text PDF
Article Synopsis
  • - The study identifies a new group of basal forebrain neurons that express Npas1, a transcription factor associated with neuropsychiatric disorders, which are distinct from other known neurons like parvalbumin and cholinergic neurons.
  • - These Npas1 neurons are predominantly GABAergic, with a much higher density than neighboring neurons, and project to several brain regions related to sleep-wake regulation and motivation.
  • - Activating these neurons increases wakefulness and alters sleep patterns, suggesting their involvement in motivation-driven wakefulness and stress-related insomnia, making them valuable for understanding sleep disorders and neuropsychiatric conditions.
View Article and Find Full Text PDF

Estimates of juvenile survival are critical for informing population dynamics and the ecology of fish, yet these demographic parameters are difficult to measure. Here, we demonstrate that advances in animal tracking technology provide opportunities to evaluate survival of juvenile tagged fish. We implemented a whole-lake telemetry array in conjunction with small acoustic tags (including tags < 1.

View Article and Find Full Text PDF

The genomic landscape of Stone Age Europe was shaped by multiple migratory waves and population replacements, but different regions do not all show similar patterns. To refine our understanding of the population dynamics before and after the dawn of the Neolithic, we generated and analyzed genomic sequence data from human remains of 56 individuals from the Mesolithic, Neolithic, and Eneolithic across Central and Eastern Europe. We found that Mesolithic European populations formed a geographically widespread isolation-by-distance zone ranging from Central Europe to Siberia, which was already established 10,000 years ago.

View Article and Find Full Text PDF

() is a filamentous fungus that infects cereals such as corn, wheat, and barley, with serious impact on yield as well as quality when the grain is contaminated with mycotoxins. Despite the huge impact of on food security and mammalian health, the mechanisms used by to export virulence factors during infection are not fully understood and may involve non-classical secretory pathways. Extracellular vesicles (EVs) are lipid-bound compartments produced by cells of all kingdoms that transport several classes of macromolecules and are implicated in cell-cell communication.

View Article and Find Full Text PDF
Article Synopsis
  • Many neuropsychiatric disorders and sleep disruptions impair attention, impacting workplace productivity and raising accident risks, hence understanding neural pathways is crucial.
  • The study tests how basal forebrain neurons containing parvalbumin affect vigilant attention in mice, specifically if activating these neurons can counteract the negative effects of sleep deprivation.
  • Results showed that stimulating these neurons improved attention and reaction times despite sleep deprivation, while inhibiting them slowed reaction times, confirming their significant role in attention regulation.
View Article and Find Full Text PDF

Extracellular vesicles (EVs) from human fungal pathogens have been implicated in fungal virulence, yet little is known about their role in the host-pathogen interaction. Progress has been hampered by the lack of a specific marker for fungal EVs that can be used to monitor EV isolation and tracking in biological systems. Here we report the effect of a gene knockout on the production, properties, and role of EVs in the virulence of .

View Article and Find Full Text PDF

Autotransporters (ATs) are a large family of bacterial secreted and outer membrane proteins that encompass a wide range of enzymatic activities frequently associated with pathogenic phenotypes. We present the structural and functional characterisation of a subtilase autotransporter, Ssp, from the opportunistic pathogen Serratia marcescens. Although the structures of subtilases have been well documented, this subtilisin-like protein is associated with a 248 residue β-helix and itself includes three finger-like protrusions around its active site involved in substrate interactions.

View Article and Find Full Text PDF

Background: NHS England commissioned four independent service providers to pilot low-calorie diet programmes to drive weight loss, improve glycaemia and potentially achieve remission of Type 2 Diabetes across 10 localities. Intervention fidelity might contribute to programme success. Previous research has illustrated a drift in fidelity in the design and delivery of other national diabetes programmes.

View Article and Find Full Text PDF

Disturbances to aquatic habitats are not uniformly distributed within the Great Lakes and acute effects can be strongest in nearshore areas where both landscape and within lake effects can have strong influence. Furthermore, different fish species respond to disturbances in different ways. A means to identify and evaluate locations and extent of disturbances that affect fish is needed throughout the Great Lakes.

View Article and Find Full Text PDF

The emergence of SARS-CoV-2 variants has exacerbated the COVID-19 global health crisis. Thus far, all variants carry mutations in the spike glycoprotein, which is a critical determinant of viral transmission being responsible for attachment, receptor engagement and membrane fusion, and an important target of immunity. Variants frequently bear truncations of flexible loops in the N-terminal domain (NTD) of spike; the functional importance of these modifications has remained poorly characterised.

View Article and Find Full Text PDF

Experimental evidence has implicated multiple neurotransmitter systems in either the direct or indirect modulation of cortical arousal and attention circuitry. In this review, we selectively focus on three such systems: 1) norepinephrine (NE)-containing neurons of the locus coeruleus (LC), 2) acetylcholine (ACh)-containing neurons of the basal forebrain (BF), and 3) parvalbumin (PV)-containing gamma-aminobutyric acid neurons of the BF. Whereas BF-PV neurons serve as a rapid and transient arousal system, LC-NE and BF-ACh neuromodulation are typically activated on slower but longer-lasting timescales.

View Article and Find Full Text PDF
Article Synopsis
  • Researchers found that editing the α3 GABA-receptor subunit in specific brain cells can increase delta waves during sleep, which are linked to restorative sleep benefits.* -
  • This editing process, done using CRISPR-Cas9, significantly reduced inhibitory currents in these neurons, suggesting a stronger response to sleep regulation.* -
  • The study suggests that targeting α3 GABA receptors could be a new strategy to improve deep sleep and its associated health benefits.*
View Article and Find Full Text PDF

Background: Invasive bacterial infections (IBI) in children present a difficult clinical challenge. They are often life-threatening, however in the early stages they can be hard to differentiate from benign viral infections. This leaves clinicians with the risk of missing a serious IBI diagnosis or inappropriately using antimicrobials in a child with a viral infection- contributing to the ongoing development of increased antimicrobial resistance.

View Article and Find Full Text PDF

Background: The COVID-19 pandemic has highlighted the importance of whole genome sequencing (WGS) of SARS-CoV-2 to inform public health policy. By enabling definition of lineages it facilitates tracking of the global spread of the virus. The evolution of new variants can be monitored and knowledge of specific mutations provides insights into the mechanisms through which the virus increases transmissibility or evades immunity.

View Article and Find Full Text PDF

SARS-CoV-2 can efficiently infect both children and adults, albeit with morbidity and mortality positively associated with increasing host age and presence of co-morbidities. SARS-CoV-2 continues to adapt to the human population, resulting in several variants of concern (VOC) with novel properties, such as Alpha and Delta. However, factors driving SARS-CoV-2 fitness and evolution in paediatric cohorts remain poorly explored.

View Article and Find Full Text PDF