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SARS-CoV-2 vaccination induces immunological T cell memory able to cross-recognize variants from Alpha to Omicron
We address whether T cell responses induced by different vaccine platforms (mRNA-1273, BNT162b2, Ad26.COV2.S, NVX-CoV2373) cross-recognize early SARS-CoV-2 variants. T cell responses to early variants were preserved across vaccine platforms. By contrast, significant overall decreases were observed for memory B cells and neutralizing antibodies. In subjects ∼6 months post-vaccination, 90% (CD4+) and 87% (CD8+) of memory T cell responses were preserved against variants on average by AIM assay, and 84% (CD4+) and 85% (CD8+) preserved against Omicron. Omicron RBD memory B cell recognition was substantially reduced to 42% compared to other variants. T cell epitope repertoire analysis revealed a median of 11 and 10 spike epitopes recognized by CD4+ and CD8+ T cells, with average preservation > 80% for Omicron. Functional preservation of the majority of T cell responses may play an important role as second-level defenses against diverse variants
Genetic characterisation of Echinocephalus spp. (Nematoda: Gnathostomatidae) from marine hosts in Australia
We genetically characterised larval and adult specimens of species of Echinocephalus Molin, 1858 (Gnathostomatidae) collected from various hosts found within Australian waters. Adult specimens of Echinocephalus were collected from a dasyatid stingray [Pastinachus ater (Macleay); n = 2] from Moreton Bay, Queensland and larvae from a hydrophiine sea snake [Hydrophis peronii (Duméril); n = 3] from Cape York Peninsula, Queensland, from an octopus (Octopus djinda Amor & Hart; n = 3) from Fremantle, Western Australia and from a lucinid bivalve [Codakia paytenorum (Iredale); n = 5] from Heron Island, Queensland Australia. All nematode samples were identified morphologically and genetically characterised using the small subunit nuclear ribosomal DNA (SSU). Some morphological differences were identified between previous studies of Echinocephalus spp. and those observed herein but the significance of these differences remains unresolved. Molecular phylogenetic analyses revealed that larval Echinocephalus sp. from H. peronii and C. paytenorum in Australia were very similar (with strong nodal support) to larval Echinocephalus sp. infecting two fish species from Egypt, Saurida undosquamis (Richardson) (Synodontidae) and Pagrus pagrus (Linnaeus) (Sparidae). The SSU sequences of larval Echinocephalus sp. from O. djinda and adults from P. ater formed a well-supported clade with that of adult E. overstreeti Deardorff and Ko, 1983 from the Port Jackson shark, Heterodontus portusjacksoni (Meyer), as well as that of the larval Echinocephalus sp., from the common carp (Cyprinus carpio Linnaeus) from Egypt. This study extends the intermediate host range of Echinocephalus larvae by including a sea snake for the first time. Findings of this study highlight the importance of genetic characterisation of larval and adult specimens of Echinocephalus spp. to resolve the current difficulties in the taxonomy of this genus
Clostridioides difficile infection and One Health: An equine perspective
Clostridioides (Clostridium) difficile presents a significant health risk to humans and animals. The complexity of the bacterial–host interaction affecting pathogenesis and disease development creates an ongoing challenge for epidemiological studies, control strategies and prevention planning. The recent emergence of human disease caused by strains of C. difficile found in animals adds to mounting evidence that C. difficile infection (CDI) may be a zoonosis. In equine populations, C. difficile is a known cause of diarrhoea and gastrointestinal inflammation, with considerable mortality and morbidity. This has a significant impact on both the well-being of the animal and, in the case of performance and production animals, it may have an adverse economic impact on relevant industries. While C. difficile is regularly isolated from horses, many questions remain regarding the impact of asymptomatic carriage as well as optimization of diagnosis, testing and treatment. This review provides an overview of our understanding of equine CDI while also identifying knowledge gaps and the need for a holistic One Health approach to a complicated issue
Morphological and functional divergence of the lower jaw between native and invasive red foxes
The introduction of European red foxes in Australia in the late mid-nineteenth century has resulted in the spread of this invasive species across the continent. The morphological and functional divergence of this relatively recently introduced population has not been explored to date, yet it may provide unique insights into adaptability of this widespread carnivore to very different environments. Here we used three-dimensional geometric morphometric approaches and dissections to explore differences in mandible form and function between two populations: one from France and the other from Western Australia. Bite force was predicted for Australian foxes using partial least squares (PLS) regression models based on the observed covariation between estimated bite force (from muscle dissections) and mandible form in French foxes. Muscle contributions were estimated based on Euclidean distances between landmarks that provide insights into muscle lever arms. Despite the greater sample size, Australian foxes show reduced variability in mandible shape compared with French foxes. The mandibles of adult French foxes tend to be slightly smaller and they also strongly differ in shape from the Australian foxes in functionally important areas of the mandible such as muscle insertion areas. This is accompanied by significant differences in the predicted bite force, even relative to size, and muscle contribution: the bite of Australian foxes is weaker and they show greater use of their temporalis muscle compared to French foxes. The reduced variability suggests a founder effect or stabilizing selection on a specific morphology, which was supported by statistical tests. The corresponding anatomical traits suggest different functional demands likely due to differences in diet or competition. Future studies investigating the drivers of variation in mandible shape in native and invasive populations, including data from the original source of the Australian introductions, are needed to better understand the observed differences
qPCR assays for sensitive and rapid detection of Quambalaria species from plant tissues
Several species from the genus Quambalaria (order Microstromatales) cause diseases on eucalypts (Eucalyptus and related genera) both in plantations and natural ecosystems. We developed real-time quantitative PCR (qPCR) assays to rapidly detect and distinguish five Quambalaria species. The design of the species-specific qPCR assay for each species, Q. pitereka (PIT), Q. coyrecup (COR), Q. cyanescens (CYN), Q. pusilla (PUS), and Q. eucalypti (EUC), was based on the ITS region and was evaluated for specificity and sensitivity. The PIT, COR, and CYN qPCR assays could amplify as little as 10 fg µl−1 from pure cultures, whereas PUS and EUC qPCR assays could amplify 100 fg µl−1 of their target species. The PIT, COR, and CYN qPCR assays were further validated using naturally and artificially infected samples of their plant host Corymbia calophylla. These assays will be used for rapid diagnostics and future experiments on the infection process
A Nurse Practitioner service designed to address the health needs of children living in housing instability: A non‐randomised, concurrent mixed methods study protocol
In 2019–2020 we conducted a pilot study of a Nurse Practitioner clinic working with housing insecure children (0–18 years) that found high levels of developmental delay, missed immunizations and dental caries. This present non-randomized, concurrent mixed-methods study protocol explains the next phase of the research designed proving proof of concept for a Nurse Practitioner model of care for these vulnerable children. Focusing on identifying and understanding clinic admission processes, tracking referral pathways and uptake, and how many vulnerable children miss potential care and why. This will help us to understand and address gaps in health service delivery for this cohort.
Design
The study uses a concurrent mixed- method design where both qualitative and quantitative data are collected during the same period (between January 2021 and March 2022 as per the funding timeline).
Methods
The concurrent mixed-method design will collect data from:
• A comprehensive assessment tool used by the Nurse Practitioner to evaluate the child accessing specialist homeless services, which assess their mental, physical and social health needs.
• Documentation about the child's referral needs and uptake by disadvantage families.
• Interviews with housing insecure families, and staff/managers of the specialist homeless service.
• A review of Nurse Practitioner case notes.
• Surveys of families with children accessing the Nurse Practitioner service.
Discussion
Addressing the childhood impacts of family homelessness is of global importance. Structural equation modelling, from the surveys and in-depth health assessments along with the thematic analysis of the interviews with parents and staff/managers provide an understanding of the relationships between referral uptake and variables such as education, homelessness and transport accessibility. Investigating the enablers and barriers to the usual health access and our extended referral uptake impacted by family homelessness enables a better understanding of the current health gaps.
Impact
Just over one fifth of Australian children live with their families in some form of housing instability including homelessness. These children, aged from birth to 18 years, are often disconnected from health and similar social institutions, making them an underserviced population. Our research investigates a Nurse Practitioner services that helps reconnect children with services to help avoid poor long-term health outcomes
QuantiFERON‐cytomegalovirus to predict clinically significant cytomegalovirus infection after allogeneic hematopoietic stem cell transplantation
Background
Controlling cytomegalovirus (CMV) infection through prophylaxis or pre-emptive therapy remains an important contributor to outcomes after allogeneic hematopoetic stem cell transplant (alloHCT). Predicting clinically significant CMV infection (csCMVi) after day 100 remains a challenge.
Methods
We examined the abilty of the QuantiFERON-CMV assay (QFN-CMV) at day 100 (d100) and day 150 (d150) after alloHCT to predict csCMVi after these time points, with median follow-up of 3.1 years (range 1.3–4.3 years).
Results
In 46 transplants (donor seropositive (D+) recipient seronegative (R-) = 12, D+R+ = 25, D-R+ = 9; matched related = 13, unrelated donor = 32, haploidentical = 1), for the prediction of freedom from csCMVi >d100, QFN-CMVd100 (positive compared to negative/indeterminate) had sensitivity 62% (23/37), specificity 100% (9/9), positive predictive value 100% (23/23), and negative predictive value 39% (9/23). For the prediction of freedom from csCMVi >d150, QFN-CMVd150 (positive compared to negative/indeterminate) had sensitivity 62% (18/29), specificity 83% (5/6), positive predictive value 95% (18/19), and negative predictive value 31% (5/16).
Conclusion
Positive QFN-CMV at d100 and d150 strongly predicted freedom from csCMVi after these time points. QFN-CMV could be utilized to predict the need for pre-emptive therapy and CMV viral load monitoring after day 100 post-alloHCT
Supporting Aboriginal and Torres Strait Islander Families to Stay Together from the Start (SAFeST Start): Urgent call to action to address crisis in infant removals
Reducing the rate of over-representation of Aboriginal and Torres Strait Islander children in out-of-home care (OOHC) is a key Closing the Gap target committed to by all Australian governments. Current strategies are failing. The “gap” is widening, with the rate of Aboriginal and Torres Strait Islander children in OOHC at 30 June 2020 being 11 times that of non-Indigenous children. Approximately, one in five Aboriginal and Torres Strait Islander children entering OOHC each year are younger than one year. These figures represent compounding intergenerational trauma and institutional harm to Aboriginal and Torres Strait Islander families and communities. This article outlines systemic failures to address the needs of Aboriginal and Torres Strait Islander parents during pregnancy and following birth, causing cumulative harm and trauma to families, communities and cultures. Major reform to child and family notification and service systems, and significant investment to address this crisis, is urgently needed. The Family Matters Building Blocks and five elements of the Aboriginal and Torres Strait Islander Child Placement Principle (Prevention, Participation, Partnerships, Placement and Connection) provide a transformative foundation to address historical, institutional, well-being and socioeconomic drivers of current catastrophic trajectories. The time for action is now
Adaptalight: An inexpensive PAR sensor system for daylight harvesting in a Micro Indoor Smart Hydroponic System
Environmental changes and the reduction in arable land have led to food security concerns around the world, particularly in urban settings. Hydroponic soilless growing methods deliver plant nutrients using water, conserving resources and can be constructed nearly anywhere. Hydroponic systems have several complex attributes that need to be managed, and this can be daunting for the layperson. Micro Indoor Smart Hydroponics (MISH) leverage Internet of Things (IoT) technology to manage the complexities of hydroponic techniques, for growing food at home for everyday citizens. Two prohibitive costs in the advancement of MISH systems are power consumption and equipment expense. Reducing cost through harvesting ambient light can potentially reduce power consumption but must be done accurately to sustain sufficient plant yields. Photosynthetic Active Radiation (PAR) meters are commercially used to measure only the light spectrum that plants use, but are expensive. This study presents Adaptalight, a MISH system that harvests ambient light using an inexpensive AS7265x IoT sensor to measure PAR. The system is built on commonly found IoT technology and a well-established architecture for MISH systems. Adpatalight was deployed in a real-world application in the living space of an apartment and experiments were carried out accordingly. A two-phase experiment was conducted over three months, each phase lasting 21 days. Phase one measured the IoT sensor’s capability to accurately measure PAR. Phase two measured the ability of the system to harvest ambient PAR light and produce sufficient yields, using the calibrated IoT sensor from phase one. The results showed that the Adaptalight system was successful in saving a significant amount of power, harvesting ambient PAR light and producing yields with no significant differences from the control. The amount of power savings would be potentially greater in a location with more ambient light. Additionally, the findings show that, when calibrated, the AS7265x sensor is well suited to accurately measure PAR light in MISH systems
Mendelian randomisation study of smoking, alcohol, and coffee drinking in relation to Parkinson’s Disease
Background:Previous studies showed that lifestyle behaviors (cigarette smoking, alcohol, coffee) are inversely associated with Parkinson’s disease (PD). The prodromal phase of PD raises the possibility that these associations may be explained by reverse causation. Objective:To examine associations of lifestyle behaviors with PD using two-sample Mendelian randomisation (MR) and the potential for survival and incidence-prevalence biases. Methods:We used summary statistics from publicly available studies to estimate the association of genetic polymorphisms with lifestyle behaviors, and from Courage-PD (7,369 cases, 7,018 controls; European ancestry) to estimate the association of these variants with PD. We used the inverse-variance weighted method to compute odds ratios (ORIVW) of PD and 95%confidence intervals (CI). Significance was determined using a Bonferroni-corrected significance threshold (p = 0.017). Results:We found a significant inverse association between smoking initiation and PD (ORIVW per 1-SD increase in the prevalence of ever smoking = 0.74, 95%CI = 0.60–0.93, p = 0.009) without significant directional pleiotropy. Associations in participants ≤67 years old and cases with disease duration ≤7 years were of a similar size. No significant associations were observed for alcohol and coffee drinking. In reverse MR, genetic liability toward PD was not associated with smoking or coffee drinking but was positively associated with alcohol drinking. Conclusion:Our findings are in favor of an inverse association between smoking and PD that is not explained by reverse causation, confounding, and survival or incidence-prevalence biases. Genetic liability toward PD was positively associated with alcohol drinking. Conclusions on the association of alcohol and coffee drinking with PD are hampered by insufficient statistical power