New Day

In the spirit of Indigenous storytelling and cultural significance, the artwork portrays a profound narrative. At its core is the image of a radiant light bulb, its rays symbolizing the birth of a new idea, akin to the moment when a light bulb ignites in one's mind. Yet, within this light resides a Raven, a sacred and central figure in many coastal First Nations stories. Raven embodies the timeless tale of light, a story woven through the fabric of Indigenous cultures

Determination of Endothelial Stalk versus Tip Cell Potential during Angiogenesis by H2.0-like Homeobox-1

SummaryTissue branching morphogenesis requires the hierarchical organization of sprouting cells into leading “tip” and trailing “stalk” cells [1, 2]. During new blood vessel branching (angiogenesis), endothelial tip cells (TCs) lead sprouting vessels, extend filopodia, and migrate in response to gradients of the secreted ligand, vascular endothelial growth factor (Vegf) [3]. In contrast, adjacent stalk cells (SCs) trail TCs, generate the trunk of new vessels, and critically maintain connectivity with parental vessels. Here, we establish that h2.0-like homeobox-1 (Hlx1) determines SC potential, which is critical for angiogenesis during zebrafish development. By combining a novel pharmacological strategy for the manipulation of angiogenic cell behavior in vivo with transcriptomic analyses of sprouting cells, we identify the uniquely sprouting-associated gene, hlx1. Expression of hlx1 is almost entirely restricted to sprouting endothelial cells and is excluded from adjacent nonangiogenic cells. Furthermore, Hlx1 knockdown reveals its essential role in angiogenesis. Importantly, mosaic analyses uncover a cell-autonomous role for Hlx1 in the maintenance of SC identity in sprouting vessels. Hence, Hlx1-mediated maintenance of SC potential regulates angiogenesis, a finding that may have novel implications for sprouting morphogenesis of other tissues

Folate status assessment history: implications for measurement of biomarkers in NHANES12345

This article presents a historical perspective on the different methods used to measure folate status in populations and clinical settings. I discuss some of the advantages and limitations of these procedures. For >50 y researchers have used microbiological assay methods to assess folate status in clinical settings and in population-based studies, such as NHANES. Serum and red blood cell folate values obtained with the Lactobacillus casei assay have formed the basis for current ranges and cutoffs for the establishment of folate sufficiency and for the current dietary reference intakes for folate. Over the past 30 y competitive folate protein binding assays, which are available in kit form, have supplanted microbiological assays in many clinical laboratories because of their ease of use. Several NHANES cycles have used these assays. Folate concentrations obtained with these kits are lower than those from microbiological assays and show a wide variation between different protein binding assay kits. This variation has complicated the setting of values for normal ranges of folate status and the comparison of status changes between different NHANES cycles. The recent development of mass spectrometry methods for folate opens up the possibility of measurement of individual folate vitamers such as folic acid. Past experience with microbiological and competitive protein binding assays indicates some of the technical problems that research will need to address before this promise becomes reality

Magnetic Properties and Phase Transitions of Gadolinium-infused Carbon Nanotubes

Carbon nanotube (CNT)/metal-cluster-based composites are envisioned as new materials that possess unique electronic properties which may be utilized in a variety of future applications. Superparamagnetic behavior was reported for CNTs with Gd ions introduced into the CNT openings by internal loading with an aqueous GdCl3 chemical process. In the current work, the magnetic properties of the CNT/Gd composites were obtained by the joining and annealing of Gd metal and CNTs at 850 degrees C for 48 h. Energy dispersive X-ray analysis shows the presence of Gd intermingled with the CNT walls with maximum and average Gd concentrations of about 20% and 4% (by weight), respectively. The Gd clusters have a non-uniform distribution and are mostly concentrated at the ends of the CNTs. A ferromagnetic-type transition at TC ~ to 320K, accompanied by jump like change in magnetization and temperature hysteresis typical for the temperature induced first order phase transitions has been observed by magnetization measurements. It was found that Gd infused into the CNTs by the annealing results in a first order paramagnetic-ferromagnetic transition at TC = 320K

Estimation of the Rate of SNP Genotyping Errors From DNA Extracted From Different Tissues

High density single nucleotide polymorphism (SNP) genotyping panels provide an alternative to microsatellite markers for genome scans. However, genotype errors have a major impact on power to detect linkage or association and are difficult to detect for SNPs. We estimated error rates with the Affymetrix GeneChip® SNP platform in samples from a family with a mixed set of monozygotic (MZ) and dizygotic (DZ) triplets using lymphocyte, buccal DNA and samples from whole genome amplification using the multiple displacement amplification (MDA) technique. The average call rate from 58,960 SNPs for five genomic samples was 99.48%. Comparison of results for the MZ twins showed only three discordant genotypes (concordance rate 99.995%). The mean concordance rate for comparisons of samples from lymphocyte and buccal DNA was 99.97%. Mendelian inconsistencies were identified in 46 SNPs with errors in one or more family members, a rate of 0.022%. Observed genotype concordance rates between parents, between parents and children, and among siblings were consistent with previously reported allele frequencies and Hardy-Weinberg equilibrium. Using the MDA technique, results for two samples had equivalent high accuracy to results with genomic samples. However, the SNP call rate for the remaining seven samples varied from 72.5% to 99.5%, with an average of 86.11%. Quality of the DNA sample following the MDA reaction appears to be the critical factor in SNP call rate for MDA samples. Our results demonstrate highly accurate and reproducible genotyping for the Affymetrix GeneChip® Human Mapping Set in lymphocyte and buccal DNA samples.</p

In vivo Bioluminescence Imaging of Burkholderia mallei Respiratory Infection and Treatment in the Mouse Model

Bioluminescent imaging (BLI) technology is a powerful tool for monitoring infectious disease progression and treatment approaches. BLI is particularly useful for tracking fastidious intracellular pathogens that might be difficult to recover from certain organs. Burkholderia mallei, the causative agent of glanders, is a facultative intracellular pathogen and has been classified by the CDC as a Category B select agent due to its highly infectious nature and potential use as a biological weapon. Very little is known regarding pathogenesis or treatment of glanders. We investigated the use of bioluminescent reporter constructs to monitor the dynamics of infection as well as the efficacy of therapeutics for B. mallei in real-time. A stable luminescent reporter B. mallei strain was created using the pUTmini-Tn5::luxKm2 plasmid and used to monitor glanders in the BALB/c murine model. Mice were infected via the intranasal route with 5 × 103 bacteria and monitored by BLI at 24, 48, and 72 h. We verified that our reporter construct maintained similar virulence and growth kinetics compared to wild-type B. mallei and confirmed that it maintains luminescent stability in the presence or absence of antibiotic selection. The luminescent signal was initially seen in the lungs, and progressed to the liver and spleen over the course of infection. We demonstrated that antibiotic treatment 24 h post-infection resulted in reduction of bioluminescence that can be attributed to decreased bacterial burden in target organs. These findings suggest that BLI can be used to monitor disease progression and efficacy of therapeutics during glanders infections. Finally, we report an alternative method to mini-Tn5::luxKm2 transposon using mini-Tn7-lux elements that insert site-specifically at known genomic attachment sites and that can also be used to tag bacteria

Developing a faculty wide WIL program for science

Problem Uptake of Work-Integrated Learning (WIL) is far less in the natural and physical sciences than other STEM disciplines at the University of Tasmania, many of which have a requirement for WIL for professional accreditation, including ICT, Engineering, surveying and agriculture. This disparity is consistent with national trends. Despite these pockets of activity in specific disciplines, we currently lack a generic WIL program suited to broad implementation across the Faculty of Science, Engineering and Technology and a mechanism for students and academic staff to identify and engage with industry partners. Plan This is one of six ‘Lighthouse Projects’ co-funded by the Australian Council of Deans of Science, in the sub-theme of ‘Setting up Faculty WIL programs’ with the project undertaking a review of WIL programs, including student preparation and program delivery and support, to inform the development of a generic science unit for on- and off-campus WIL in our Faculty. WIL is generally understood to be the approaches and strategies that integrate theory with its practice in the workplace. WIL allows students to develop depth of understanding through the application of the knowledge and skills of their chosen discipline, while enabling students to improve their future employability outcomes. The University of Tasmania aims to provide graduates with the skills required for participation in the national and international work environments, and this project aims to extend the curriculum by providing real world experiences for our students. Our project aims to include provision for student placement in industry, but also for on-campus simulation of the workplace, combining an authentic experience with critical reflective practice. Action Phase 1 of the project involved a review of established placement and project-based WIL units and/or programs in Science or related disciplines. Three of these units are offered by our Faculty in the disciplines of Agriculture and Food Systems, Engineering, and Information and Communication Technology (ICT), with one other from the Tasmanian School of Business and Economics. Another three WIL programs were from the Science faculties at Deakin University, Monash University and The University of Melbourne. Collated information was used to inform the development of learning outcomes, support, delivery and assessment of a generic WIL elective unit for the natural and physical sciences at the University of Tasmania. Our reflections on the project A common assessment strategy in WIL is for students to critically self-reflect on the application of knowledge and skills in their professional work. Our review of existing programs indicated that students are taught and practice critical self-reflection to understand their strengths and development needs in the context of their readiness for work. Academics and students in the Faculty will be consulted in the next phase of the project to benchmark the use of critical self-reflection and authentic assessment. A Faculty Industry Reference Group will be formed for consultation and networking purposes. Collated information will inform the development of activities to ensure that students from diverse science disciplines can achieve the intended learning outcomes in the generic WIL unit. Focus group discussions with academic staff will be a precursor to developing a framework for a program in WIL in the Faculty that is aligned with the strategic aims of the university

Intravital FRAP imaging using an E-cadherin-GFP mouse reveals disease- and drug-dependent dynamic regulation of cell-cell junctions in live tissue

E-cadherin-mediated cell-cell junctions play a prominent role in maintaining the epithelial architecture. The disruption or deregulation of these adhesions in cancer can lead to the collapse of tumor epithelia that precedes invasion and subsequent metastasis. Here we generated an E-cadherin-GFP mouse that enables intravital photobleaching and quantification of E-cadherin mobility in live tissue without affecting normal biology. We demonstrate the broad applications of this mouse by examining E-cadherin regulation in multiple tissues, including mammary, brain, liver, and kidney tissue, while specifically monitoring E-cadherin mobility during disease progression in the pancreas. We assess E-cadherin stability in native pancreatic tissue upon genetic manipulation involving Kras and p53 or in response to anti-invasive drug treatment and gain insights into the dynamic remodeling of E-cadherin during in situ cancer progression. FRAP in the E-cadherin-GFP mouse, therefore, promises to be a valuable tool to fundamentally expand our understanding of E-cadherin-mediated events in native microenvironments