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result(s) for
"Richardson, Janet E."
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Physiological Responses of Firefighters Wearing Level 3 Chemical Protective Suits While Working in Controlled Hot Environments
2001
Firefighters in Queensland are exposed to hot, humid weather conditions that contribute to the overall workload encountered during emergency operations. Responding to certain hazardous material incidents requires firefighters to wear fully encapsulated chemical protective suits for a maximum period of 20 minutes. The nature of these suits, combined with workload and environmental conditions, poses a potential heat stress problem for firefighters. This study evaluates the heat-induced physiological responses of firefighters while wearing fully encapsulated chemical protective suits in a senes of controlled thermal environments. Heart rate, body (aural) temperature, blood pressure, fluid loss, and a rating of perceived exertion were measured to evaluate the effect of increasing ambient air temperature during the performance of standard tasks. The results of the study indicated that the significant increase in heart rate, body temperature, and blood pressure was directly related to the increase in air temperature. The research indicates that the recommended suit wearing time of 20 minutes provided adequate physiological protection under the research conditions.
Journal Article
The Importance of Frailty in the Assessment of Influenza Vaccine Effectiveness Against Influenza-Related Hospitalization in Elderly People
by
Langley, Joanne
,
Ambrose, Ardith
,
Webster, Duncan
in
Aged
,
Aged, 80 and over
,
Case-Control Studies
2017
Background. Influenza is an important cause of morbidity and mortality among older adults. Even so, effectiveness of influenza vaccine for older adults has been reported to be lower than for younger adults, and the impact of frailty on vaccine effectiveness (VE) and outcomes is uncertain. We aimed to study VE against influenza hospitalization in older adults, focusing on the impact of frailty. Methods. We report VE of trivalent influenza vaccine (TIV) in people ≥65 years of age hospitalized during the 2011–2012 influenza season using a multicenter, prospective, test-negative case-control design. A validated frailty index (FI) was used to measure frailty. Results. Three hundred twenty cases and 564 controls (mean age, 80.6 and 78.7 years, respectively) were enrolled. Cases had higher baseline frailty than controls (P = .006). In the fully adjusted model, VE against influenza hospitalization was 58.0% (95% confidence interval [CI], 34.2%–73.2%). The contribution of frailty was important; adjusting for frailty alone yielded a VE estimate of 58.7% (95% CI, 36.2%–73.2%). VE was 77.6% among nonfrail older adults and declined as frailty increased. Conclusions. Despite commonly held views that VE is poor in older adults, we found that TIV provided good protection against influenza hospitalization in older adults who were not frail, though VE diminished as frailty increased.
Journal Article
Rapid remodeling of the soil lipidome in response to a drying-rewetting event
by
Farris, Yuliya
,
Nakayasu, Ernesto S.
,
Bramer, Lisa M.
in
Acclimatization
,
Bacteria
,
BASIC BIOLOGICAL SCIENCES
2023
Background
Microbiomes contribute to multiple ecosystem services by transforming organic matter in the soil. Extreme shifts in the environment, such as drying-rewetting cycles during drought, can impact the microbial metabolism of organic matter by altering microbial physiology and function. These physiological responses are mediated in part by lipids that are responsible for regulating interactions between cells and the environment. Despite this critical role in regulating the microbial response to stress, little is known about microbial lipids and metabolites in the soil or how they influence phenotypes that are expressed under drying-rewetting cycles. To address this knowledge gap, we conducted a soil incubation experiment to simulate soil drying during a summer drought of an arid grassland, then measured the response of the soil lipidome and metabolome during the first 3 h after wet-up.
Results
Reduced nutrient access during soil drying incurred a replacement of membrane phospholipids, resulting in a diminished abundance of multiple phosphorus-rich membrane lipids. The hot and dry conditions increased the prevalence of sphingolipids and lipids containing long-chain polyunsaturated fatty acids, both of which are associated with heat and osmotic stress-mitigating properties in fungi. This novel finding suggests that lipids commonly present in eukaryotes such as fungi may play a significant role in supporting community resilience displayed by arid land soil microbiomes during drought. As early as 10 min after rewetting dry soil, distinct changes were observed in several lipids that had bacterial signatures including a rapid increase in the abundance of glycerophospholipids with saturated and short fatty acid chains, prototypical of bacterial membrane lipids. Polar metabolites including disaccharides, nucleic acids, organic acids, inositols, and amino acids also increased in abundance upon rewetting. This rapid metabolic reactivation and growth after rewetting coincided with an increase in the relative abundance of firmicutes, suggesting that members of this phylum were positively impacted by rewetting.
Conclusions
Our study revealed specific changes in lipids and metabolites that are indicative of stress adaptation, substrate use, and cellular recovery during soil drying and subsequent rewetting. The drought-induced nutrient limitation was reflected in the lipidome and polar metabolome, both of which rapidly shifted (within hours) upon rewet. Reduced nutrient access in dry soil caused the replacement of glycerophospholipids with phosphorus-free lipids and impeded resource-expensive osmolyte accumulation. Elevated levels of ceramides and lipids with long-chain polyunsaturated fatty acids in dry soil suggest that lipids likely play an important role in the drought tolerance of microbial taxa capable of synthesizing these lipids. An increasing abundance of bacterial glycerophospholipids and triacylglycerols with fatty acids typical of bacteria and polar metabolites suggest a metabolic recovery in representative bacteria once the environmental conditions are conducive for growth. These results underscore the importance of the soil lipidome as a robust indicator of microbial community responses, especially at the short time scales of cell-environment reactions.
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Video Abstract
Journal Article
Functional evaluation and clinical classification of BRCA2 variants
2025
Germline
BRCA2
loss-of function variants, which can be identified through clinical genetic testing, predispose to several cancers
1
,
2
,
3
,
4
–
5
. However, variants of uncertain significance limit the clinical utility of test results. Thus, there is a need for functional characterization and clinical classification of all
BRCA2
variants to facilitate the clinical management of individuals with these variants. Here we analysed all possible single-nucleotide variants from exons 15 to 26 that encode the
BRCA2
DNA-binding domain hotspot for pathogenic missense variants. To enable this, we used saturation genome editing CRISPR–Cas9-based knock-in endogenous targeting of human haploid HAP1 cells
6
. The assay was calibrated relative to nonsense and silent variants and was validated using pathogenic and benign standards from ClinVar and results from a homology-directed repair functional assay
7
. Variants (6,959 out of 6,960 evaluated) were assigned to seven categories of pathogenicity based on a VarCall Bayesian model
8
. Single-nucleotide variants that encode loss-of-function missense variants were associated with increased risks of breast cancer and ovarian cancer. The functional assay results were integrated into models from ClinGen, the American College of Medical Genetics and Genomics, and the Association for Molecular Pathology
9
for clinical classification of
BRCA2
variants. Using this approach, 91% were classified as pathogenic or likely pathogenic or as benign or likely benign. These classified variants can be used to improve clinical management of individuals with a
BRCA2
variant.
Results from a comprehensive evaluation of the function of
BRCA2
variants, particularly variants of uncertain significance, provide a useful resource to improve the clinical management of individuals who carry such genetic variants.
Journal Article
Haploinsufficiency for BRCA1 leads to cell-type-specific genomic instability and premature senescence
2015
Although BRCA1 function is essential for maintaining genomic integrity in all cell types, it is unclear why increased risk of cancer in individuals harbouring deleterious mutations in
BRCA1
is restricted to only a select few tissues. Here we show that human mammary epithelial cells (HMECs) from
BRCA1
-mutation carriers (
BRCA1
mut/+
) exhibit increased genomic instability and rapid telomere erosion in the absence of tumour-suppressor loss. Furthermore, we uncover a novel form of haploinsufficiency-induced senescence (HIS) specific to epithelial cells, which is triggered by pRb pathway activation rather than p53 induction. HIS and telomere erosion in HMECs correlate with misregulation of SIRT1 leading to increased levels of acetylated pRb as well as acetylated H4K16 both globally and at telomeric regions. These results identify a novel form of cellular senescence and provide a potential molecular basis for the rapid cell- and tissue- specific predisposition of breast cancer development associated with BRCA1 haploinsufficiency.
BRCA1 functions in all cell types to help preserve genomic stability but oncogenesis is restricted to only a few tissues. Here Sedic
et al.
demonstrate a novel
BRCA1
haploinsufficiency-induced senescence pathway in epithelial cells.
Journal Article
Single-cell integration reveals metaplasia in inflammatory gut diseases
2024
The gastrointestinal tract is a multi-organ system crucial for efficient nutrient uptake and barrier immunity. Advances in genomics and a surge in gastrointestinal diseases
1
,
2
has fuelled efforts to catalogue cells constituting gastrointestinal tissues in health and disease
3
. Here we present systematic integration of 25 single-cell RNA sequencing datasets spanning the entire healthy gastrointestinal tract in development and in adulthood. We uniformly processed 385 samples from 189 healthy controls using a newly developed automated quality control approach (scAutoQC), leading to a healthy reference atlas with approximately 1.1 million cells and 136 fine-grained cell states. We anchor 12 gastrointestinal disease datasets spanning gastrointestinal cancers, coeliac disease, ulcerative colitis and Crohn’s disease to this reference. Utilizing this 1.6 million cell resource (gutcellatlas.org), we discover epithelial cell metaplasia originating from stem cells in intestinal inflammatory diseases with transcriptional similarity to cells found in pyloric and Brunner’s glands. Although previously linked to mucosal healing
4
, we now implicate pyloric gland metaplastic cells in inflammation through recruitment of immune cells including T cells and neutrophils. Overall, we describe inflammation-induced changes in stem cells that alter mucosal tissue architecture and promote further inflammation, a concept applicable to other tissues and diseases.
The study provides a comprehensive transcriptomic atlas of the human gastrointestinal tract across the lifespan, highlighting inflammation-induced changes in epithelial stem cells that alter mucosal architecture and promote further inflammation.
Journal Article
Accommodating Dynamic Oceanographic Processes and Pelagic Biodiversity in Marine Conservation Planning
by
Richardson, Anthony J.
,
Huggett, Jenny A.
,
Beckley, Lynnath E.
in
Acoustics
,
Animals
,
Biodiversity
2011
Pelagic ecosystems support a significant and vital component of the ocean's productivity and biodiversity. They are also heavily exploited and, as a result, are the focus of numerous spatial planning initiatives. Over the past decade, there has been increasing enthusiasm for protected areas as a tool for pelagic conservation, however, few have been implemented. Here we demonstrate an approach to plan protected areas that address the physical and biological dynamics typical of the pelagic realm. Specifically, we provide an example of an approach to planning protected areas that integrates pelagic and benthic conservation in the southern Benguela and Agulhas Bank ecosystems off South Africa. Our aim was to represent species of importance to fisheries and species of conservation concern within protected areas. In addition to representation, we ensured that protected areas were designed to consider pelagic dynamics, characterized from time-series data on key oceanographic processes, together with data on the abundance of small pelagic fishes. We found that, to have the highest likelihood of reaching conservation targets, protected area selection should be based on time-specific data rather than data averaged across time. More generally, we argue that innovative methods are needed to conserve ephemeral and dynamic pelagic biodiversity.
Journal Article
A Mineral-Doped Micromodel Platform Demonstrates Fungal Bridging of Carbon Hot Spots and Hyphal Transport of Mineral-Derived Nutrients
by
Bramer, Lisa M.
,
Bhattacharjee, Arunima
,
Richardson, Jocelyn A.
in
Acids
,
biomineralization
,
Carbon
2022
Fungal species are foundational members of soil microbiomes, where their contributions in accessing and transporting vital nutrients is key for community resilience. To date, the molecular mechanisms underlying fungal mineral weathering and nutrient translocation in low-nutrient environments remain poorly resolved due to the lack of a platform for spatial analysis of biotic weathering processes. Soil fungi facilitate the translocation of inorganic nutrients from soil minerals to other microorganisms and plants. This ability is particularly advantageous in impoverished soils because fungal mycelial networks can bridge otherwise spatially disconnected and inaccessible nutrient hot spots. However, the molecular mechanisms underlying fungal mineral weathering and transport through soil remains poorly understood primarily due to the lack of a platform for spatially resolved analysis of biotic-driven mineral weathering. Here, we addressed this knowledge gap by demonstrating a mineral-doped soil micromodel platform where mineral weathering mechanisms can be studied. We directly visualize acquisition and transport of inorganic nutrients from minerals through fungal hyphae in the micromodel using a multimodal imaging approach. We found that Fusarium sp. strain DS 682, a representative of common saprotrophic soil fungus, exhibited a mechanosensory response (thigmotropism) around obstacles and through pore spaces (~12 μm) in the presence of minerals. The fungus incorporated and translocated potassium (K) from K-rich mineral interfaces, as evidenced by visualization of mineral-derived nutrient transport and unique K chemical moieties following fungus-induced mineral weathering. Specific membrane transport proteins were expressed in the fungus in the presence of minerals, including those involved in oxidative phosphorylation pathways and the transmembrane transport of small-molecular-weight organic acids. This study establishes the significance of a spatial visualization platform for investigating microbial induced mineral weathering at microbially relevant scales. Moreover, we demonstrate the importance of fungal biology and nutrient translocation in maintaining fungal growth under water and carbon limitations in a reduced-complexity soil-like microenvironment. IMPORTANCE Fungal species are foundational members of soil microbiomes, where their contributions in accessing and transporting vital nutrients is key for community resilience. To date, the molecular mechanisms underlying fungal mineral weathering and nutrient translocation in low-nutrient environments remain poorly resolved due to the lack of a platform for spatial analysis of biotic weathering processes. Here, we addressed this knowledge gap by developing a mineral-doped soil micromodel platform. We demonstrate the function of this platform by directly probing fungal growth using spatially resolved optical and chemical imaging methodologies. We found the presence of minerals was required for fungal thigmotropism around obstacles and through soil-like pore spaces, and this was related to fungal transport of potassium (K) and corresponding K speciation from K-rich minerals. These findings provide new evidence and visualization into hyphal transport of mineral-derived nutrients under nutrient and water stresses.
Journal Article
Experience-based codesign approach to improve care in Australian emergency departments for complex consumer cohorts: the MyED project protocol, Stages 1.1–1.3
2023
IntroductionEmergency department (ED) care must adapt to meet current and future demands. In Australia, ED quality measures (eg, prolonged length of stay, re-presentations or patient experience) are worse for older adults with multiple comorbidities, people who have a disability, those who present with a mental health condition, Indigenous Australians, and those with a culturally and linguistically diverse (CALD) background. Strengthened ED performance relies on understanding the social and systemic barriers and preferences for care of these different cohorts, and identifying viable solutions that may result in sustained improvement by service providers. A collaborative 5-year project (MyED) aims to codesign, with ED users and providers, new or adapted models of care that improve ED performance, improve patient outcomes and improve patient experience for these five cohorts.Methods and analysisExperience-based codesign using mixed methods, set in three hospitals in one health district in Australia. This protocol introduces the staged and incremental approach to the whole project, and details the first research elements: ethnographic observations at the ED care interface, interviews with providers and interviews with two patient cohorts—older adults and adults with a CALD background. We aim to sample a diverse range of participants, carefully tailoring recruitment and support.Ethics and disseminationEthics approval has been obtained from the Western Sydney Local Health District Human Research Ethics Committee (2022/PID02749-2022/ETH02447). Prior informed written consent will be obtained from all research participants. Findings from each stage of the project will be submitted for peer-reviewed publication. Project outputs will be disseminated for implementation more widely across New South Wales, Australia.
Journal Article
Influenza vaccine effectiveness to prevent influenza-related hospitalizations and serious outcomes in Canadian adults over the 2011/12 through 2013/14 influenza seasons: A pooled analysis from the Canadian Immunization Research Network (CIRN) Serious Outcomes Surveillance (SOS Network)
by
Langley, Joanne M.
,
Poirier, Andre
,
Smith, Stephanie
in
Adults
,
Allergy and Immunology
,
Canada
2018
Ongoing assessment of influenza vaccine effectiveness (VE) is critical to inform public health policy. This study aimed to determine the VE of trivalent influenza vaccine (TIV) for preventing influenza-related hospitalizations and other serious outcomes over three consecutive influenza seasons.
The Serious Outcomes Surveillance (SOS) Network of the Canadian Immunization Research Network (CIRN) conducted active surveillance for influenza in adults ≥16 years (y) of age during the 2011/2012, 2012/2013 and 2013/2014 seasons in hospitals across Canada. A test-negative design was employed: cases were polymerase chain reaction (PCR)-positive for influenza; controls were PCR-negative for influenza and were matched to cases by date, admission site, and age (≥65 y or <65 y). All cases and controls had demographic and clinical characteristics (including influenza immunization status) obtained from the medical record. VE was estimated as 1-OR (odds ratio) in vaccinated vs. unvaccinated patients × 100%. The primary outcome was VE of TIV for preventing laboratory-confirmed influenza-related hospitalization; secondary outcomes included VE of TIV for preventing influenza-related intensive care unit (ICU) admission/mechanical ventilation, and influenza-related death.
Overall, 3394 cases and 4560 controls were enrolled; 2078 (61.2%) cases and 2939 (64.5%) controls were ≥65 y. Overall matched, adjusted VE was 41.7% (95% Confidence Interval (CI): 34.4–48.3%); corresponding VE in adults ≥65 y was 39.3% (95% CI: 29.4–47.8%) and 48.0% (95% CI: 37.5–56.7%) in adults <65 y, respectively. VE for preventing influenza-related ICU admission/mechanical ventilation in all ages was 54.1% (95% CI: 39.8–65.0%); in adults ≥65 y, VE for preventing influenza-related death was 74.5% (95% CI: 44.0–88.4%).
While effectiveness of TIV to prevent serious outcomes varies year to year, we demonstrate a statistically significant and clinically important TIV VE for preventing hospitalization and other serious outcomes over three seasons. Public health messaging should highlight the overall benefit of influenza vaccines over time while acknowledging year to year variability.
ClinicalTrials.gov Identifier: NCT01517191.
Journal Article