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Bactrocera tryoni (Queensland fruit fly) are polyphagous horticultural pests of eastern Australia. Heterogametic males contain a sex‐determining Y‐chromosome thought to be gene poor and repetitive. Here, we report 39 Y‐chromosome scaffolds (~700 kb) from B. tryoni identified using genotype‐by‐sequencing data and whole‐genome resequencing. Male diagnostic PCR assays validated eight Y‐scaffolds, and one (Btry4096) contained a novel gene with five exons that encode a predicted 575 amino acid protein. The Y‐gene, referred to as typo‐gyf, is a truncated Y‐chromosome paralogue of X‐chromosome gene gyf (1773 aa). The Y‐chromosome contained ~41 copies of typo‐gyf, and expression occurred in male flies and embryos. Analysis of 13 tephritid transcriptomes confirmed typo‐gyf expression in six additional Bactrocera species, including Bactrocera latifrons, Bactrocera dorsalis and Bactrocera zonata. Molecular dating estimated typo‐gyf evolved within the past 8.02 million years (95% highest posterior density 10.56–5.52 million years), after the split with Bactrocera oleae. Phylogenetic analysis also highlighted complex evolutionary histories among several Bactrocera species, as discordant nuclear (116 genes) and mitochondrial (13 genes) topologies were observed. B. tryoni Y‐sequences may provide useful sites for future transgene insertions, and typo‐gyf could act as a Y‐chromosome diagnostic marker for many Bactrocera species, although its function is unknown. [ABSTRACT FROM AUTHOR]

Introduction: Reconstruction of critical bone defects is challenging. In a substantial subgroup of patients, conventional reconstructive techniques are insufficient. Biodegradable scaffolds have emerged as a novel tissue engineering strategy for critical-sized bone defect reconstruction. A corticoperiosteal flap integrates the hosts' ability to regenerate bone and permits the creation of a vascular axis for scaffold neo-vascularisation (regenerative matching axial vascularisation-RMAV). This phase IIa study evaluates the application of the RMAV approach alongside a custom medical-grade polycaprolactone-tricalcium phosphate (mPCL-TCP) scaffold (Osteopore) to regenerate bone sufficient to heal critical size defects in lower limb defects., Methods and Analysis: This open-label, single-arm feasibility trial will be jointly coordinated by the Complex Lower Limb Clinic (CLLC) at the Princess Alexandra Hospital in Woolloongabba (Queensland, Australia), the Australian Centre for Complex Integrated Surgical Solutions (Queensland, Australia) and the Faculty of Engineering, Queensland University of Technology in Kelvin Grove (Queensland, Australia). Aiming for limb salvage, the study population (n=10) includes any patient referred to the CLLC with a critical-sized bone defect not amenable to conventional reconstructive approaches, after discussion by the interdisciplinary team. All patients will receive treatment using the RMAV approach using a custom mPCL-TCP implant. The primary study endpoint will be safety and tolerability of the reconstruction. Secondary end points include time to bone union and weight-bearing status on the treated limb. Results of this trial will help shape the role of scaffold-guided bone regenerative approaches in complex lower limb reconstruction where current options remain limited., Ethics and Dissemination: Approval was obtained from the Human Research Ethics Committee at the participating centre. Results will be submitted for publication in a peer-reviewed journal., Trial Registration Number: ACTRN12620001007921., Competing Interests: Competing interests: DH is a shareholder in Osteopore (Osteopore International, Singapore). The remaining authors declare no competing interests relating to this paper., (© Author(s) (or their employer(s)) 2023. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

3D bioprinting has been increasingly employed in skin tissue engineering for manufacturing living constructs with three-dimensional spatial precision and controlled architecture. There is however, a bottleneck in the tunability of bioinks to address specific biocompatibility challenges, functional traits and printability. Here we report on a traditional gelatin methacryloyl (GelMA) based bioink, tuned by addition of an ulvan type polysaccharide, isolated from a cultivated source of a specific Australian Ulvacean macroalgae (Ul84). Ul84 is a sulfate- and rhamnose-rich polysaccharide, resembling mammalian glycosaminoglycans that are involved in wound healing and tissue matrix structure and function. Printable bioinks were developed by addition of methacrylated Ul84 (UlMA) to GelMA solutions. The inclusion of UlMA in the bioinks facilitated the extrusion printing process by reducing yield stress. The resultant printed structures containing ulvan exhibited improved mechanical strength and regulated the rate of scaffold degradation. The 3D printed cell-laden structures with human dermal fibroblasts demonstrated high cell viability, support of cell proliferation and dermal-like properties as evidenced by the deposition of key dermal extracellular matrix components including collagen I, collagen III, elastin and fibronectin. In vitro degradation suggested the role of UlMA in supporting structural stability of the printed cellular structures. Taken together, the present work demonstrates progression towards a biocompatible and biofunctional ink that simultaneously delivers improved mechanical, structural and stability traits that are important in facilitating real world applications in skin tissue repair.

Background: Bioresorbable scaffolds (BRS) are a novel technology in coronary intervention. However, recent trials demonstrate higher rates of device failure compared to contemporary drug-eluting stents. This study sought to utilise a clinical quality registry to assess the medium-term safety of the Abbott Absorb BRS (Abbott Vascular, Santa Clara, CA, USA), in an Australian context., Methods: A prospective, observational study of 192 BRS percutaneous coronary interventions (PCI) compared to 31,773 non-BRS PCIs entered in the Victorian Cardiac Outcomes Registry from 2013 to 2017. The main outcome measure was patient-oriented composite endpoint (POCE) events comprising all-cause mortality, any myocardial infarction (MI), and any revascularisation., Results: Bioresorbable scaffolds patients (mean age 61.6±10.5 years, 79% male) were younger, had less comorbidity, less prior PCI, fewer ST elevation myocardial infarction (STEMI) presentations, lower rates of multi-lesion disease and more adjuvant devices compared to non-BRS PCI (all p<0.01). All-cause mortality was 2.1%, myocardial infarction (MI) 2.1%, scaffold thrombosis 3.1% and any revascularisation 14.1% (mean follow-up 27.4±8.9 months). POCE events occurred in 11.5% at 1 year and 16.9% at 2 years, comparable to pooled-trial data. Multivariate predictors of POCE were >1 scaffold used (odds ratio [OR] 4.6, 95% confidence interval [CI] 1.9-11.4, p<0.01) and scaffold diameter ≤2.5 mm (OR 3.3, 95% CI 1.4-7.6, p=0.02). Over 95% guideline adherence was achieved in six of eight patient selection criteria and four of six device deployment criteria., Conclusion: In an Australian setting, BRS were used in non-complex patients. Most guidelines for use were adhered to and outcomes were comparable to pooled trial data. Clinical quality registries are effective in assessing novel treatments and technologies when potential safety concerns develop., Competing Interests: Disclosures The authors declare no relationships or affiliations that may be deemed conflicts of interest. SJD’s work is supported by a National Health and Research Council of Australia grant., (Copyright © 2019 Australian and New Zealand Society of Cardiac and Thoracic Surgeons (ANZSCTS) and the Cardiac Society of Australia and New Zealand (CSANZ). All rights reserved.)