The validation of computed tomography derived radiodensity measurements of bone healing using histopathology.

Background: The early identification of delayed bone healing or a non-union is vital for prompt treatment and superior patient outcomes. Current techniques rely heavily on operator skill for interpretation and hence their reliability and repeatability may be inconsistent. This study assessed the application of computed tomography (CT) derived densiometric measurements as a quantitative tool for the assessment of bone healing.

Thickness and design features of clinical cranial implants-what should automated methods strive to replicate?

Purpose: New deep learning and statistical shape modelling approaches aim to automate the design process for patient-specific cranial implants, as highlighted by the MICCAI AutoImplant Challenges. To ensure applicability, it is important to determine if the training data used in developing these algorithms represent the geometry of implants designed for clinical use.

Methods: Calavera Surgical Design provided a dataset of 206 post-craniectomy skull geometries and their clinically used implants.

Accuracy of Orbital Shape Reconstruction-Comparative Analysis of Errors in Implant Shape Versus Implant Positioning: A Cadaveric Study.

Introduction: Orbital blowout fractures are commonly reconstructed with implants shaped to repair orbital cavity defects, restore ocular position and projection, and correct diplopia. Orbital implant shaping has traditionally been performed manually by surgeons, with more recent use of computer-assisted design (CAD). Accuracy of implant placement is also key to reconstruction.

Decision-Making in Adult Cranial Vault Reconstruction.

Learning Objectives: After studying this article, the participant should be able to: 1. Define and classify different types of cranial defects 2. Compare both autologous and alloplastic options for reconstruction 3.

SARS-CoV-2 seroprevalence in healthcare workers in a tertiary healthcare network in Victoria, Australia.

Background: Healthcare workers (HCW) are exposed to an increased risk of COVID-19 through direct contact with patients and patient environments. We calculated the; seroprevalence of SARS-CoV-2 in HCW at Eastern Health, a tertiary healthcare network in Victoria, and assessed associations with demographics, work location and role.

Methods: A cross-sectional cohort study of HCW at Eastern Health was conducted.

The investigation of bone fracture healing under intramembranous and endochondral ossification.

After trauma, fractured bone starts healing directly through bone union or indirectly through callus formation process. Intramembranous and endochondral ossification are two commonly known mechanisms of indirect healing. The present study investigated the bone fracture healing under intramembranous and endochondral ossification by developing theoretical models in conjunction with performing a series of animal experiments.

The common carotid artery provides significant pressure wave dampening in the young adult sheep.

Background: It has been established that the central elastic arteries of the mammalian circulation dampen the high pulse pressure emanating from the left ventricle, so that the pulsations in distal arterioles, such as in the cerebral circulation, are of lower amplitude than more centrally. However, the contribution of the common carotid artery (CCA) to protection of the cerebral microvasculature from high pulse pressure is not known, specifically to what extent viscoelastic energy dissipation in the arterial wall might contribute to the shock absorbing function of the large conduit arteries.

Methods: Young adult sheep (n = 6) were anaesthetised and their CCAs (n = 7) exposed.

Unified biophysical mechanism for cell-shape oscillations and cell ingression.

We describe a mechanochemical and percolation cascade that augments myosin's regulatory network to tune cytoskeletal forces. Actomyosin forces collectively generate cytoskeletal forces during cell oscillations and ingression, which we quantify by elastic percolation of the internally driven, cross-linked actin network. Contractile units can produce relatively large, oscillatory forces that disrupt crosslinks to reduce cytoskeletal forces.

Tropoelastin Implants That Accelerate Wound Repair.

A novel, pure, synthetic material is presented that promotes the repair of full-thickness skin wounds. The active component is tropoelastin and leverages its ability to promote new blood vessel formation and its cell recruiting properties to accelerate wound repair. Key to the technology is the use of a novel heat-based, stabilized form of human tropoelastin which allows for tunable resorption.

Correlating in Vitro Solubilization and Supersaturation Profiles with in Vivo Exposure for Lipid Based Formulations of the CETP Inhibitor CP-532,623.

Lipid based formulations (LBFs) are a promising formulation strategy for many poorly water-soluble drugs and have been shown previously to enhance the oral exposure of CP-532,623, an oral cholesteryl ester transfer protein inhibitor. In the current study, an in vitro lipid digestion model was used to probe the relationship between drug solubilization and supersaturation on in vitro dispersion and digestion of LBF containing long chain (LC) lipids and drug absorption in vivo. After in vitro digestion of LBF based on LC lipids, the proportion of CP-532,623 maintained in the solubilized state in the aqueous phase of the digest was highest in formulations containing Kolliphor RH 40, and in most cases outperformed equivalent formulations based on MC lipids.

Cell Sheet Morphogenesis: Dorsal Closure in Drosophila melanogaster as a Model System.

Dorsal closure is a key process during Drosophila morphogenesis that models cell sheet movements in chordates, including neural tube closure, palate formation, and wound healing. Closure occurs midway through embryogenesis and entails circumferential elongation of lateral epidermal cell sheets that close a dorsal hole filled with amnioserosa cells. Signaling pathways regulate the function of cellular structures and processes, including Actomyosin and microtubule cytoskeletons, cell-cell/cell-matrix adhesion complexes, and endocytosis/vesicle trafficking.

Quantifying dorsal closure in three dimensions.

Dorsal closure is an essential stage of Drosophila embryogenesis and is a powerful model system for morphogenesis, wound healing, and tissue biomechanics. During closure, two flanks of lateral epidermis close an eye-shaped dorsal opening that is filled with amnioserosa. The two flanks of lateral epidermis are zipped together at each canthus ("corner" of the eye).

Lymphatic Transport and Lymphocyte Targeting of a Triglyceride Mimetic Prodrug Is Enhanced in a Large Animal Model: Studies in Greyhound Dogs.

In previous studies, a triglyceride (TG) mimetic prodrug of the model immunomodulator mycophenolic acid (MPA) was shown to significantly enhance lymphatic transport of MPA-related species in the rat. The rat gastrointestinal tract, however, is somewhat different from that in higher order species such as dogs and humans and may underestimate lymphatic transport. Here the effectiveness of the prodrug strategy has been examined in conscious greyhound dogs, the GI physiology of which is more representative of that in humans.

Plasma Ion Activated Expanded Polytetrafluoroethylene Vascular Grafts with a Covalently Immobilized Recombinant Human Tropoelastin Coating Reducing Neointimal Hyperplasia.

Expanded polytetrafluoroethylene (ePTFE) vascular conduits with less than or equal to 6 mm internal diameter typically occlude due to a combination of thrombus formation and neointimal hyperplasia. We hypothesized that by layering the polymerized elastin precursor, human tropoelastin, in the synthetic vessel lumen we could mimic the internal elastic lamina and so maintain low thrombogenicity while significantly reducing smooth muscle cell proliferation. The luminal surfaces of ePTFE conduits were activated with plasma immersion ion implantation (PIII) treatment to facilitate covalent attachment of tropoelastin.

Interpretative comments specifically suggesting specialist referral increase the detection of familial hypercholesterolaemia.

Familial hypercholesterolaemia (FH) is an under-diagnosed inherited condition characterised by elevated low density lipoprotein (LDL)-cholesterol and premature coronary artery disease. The requesting general practitioner of individuals with extremely elevated LDL-cholesterol measured by St John of God Pathology receives an interpretative comment on the lipid results highlighting possible FH. We sought to determine whether specifically recommending referral to the regional Lipid Disorders Clinic (LDC) increased referral and FH detection rates.

Patient-Specific Orbital Implants: Development and Implementation of Technology for More Accurate Orbital Reconstruction.

Fracture of the orbital floor is commonly seen in facial trauma. Accurate anatomical reconstruction of the orbital floor contour is challenging. The authors demonstrate a novel method to more precisely reconstruct the orbital floor on a 50-year-old female who sustained an orbital floor fracture following a fall.

Remodeling Tissue Interfaces and the Thermodynamics of Zipping during Dorsal Closure in Drosophila.

Dorsal closure during Drosophila embryogenesis is an important model system for investigating the biomechanics of morphogenesis. During closure, two flanks of lateral epidermis (with actomyosin-rich purse strings near each leading edge) close an eye-shaped opening that is filled with amnioserosa. At each canthus (corner of the eye) a zipping process remodels the tissue interfaces between the leading edges of the lateral epidermis and the amnioserosa.

A Three-Dimensional Statistical Average Skull: Application of Biometric Morphing in Generating Missing Anatomy.

Purpose: The utilization of three-dimensional modeling technology in craniomaxillofacial surgery has grown exponentially during the last decade. Future development, however, is hindered by the lack of a normative three-dimensional anatomic dataset and a statistical mean three-dimensional virtual model. The purpose of this study is to develop and validate a protocol to generate a statistical three-dimensional virtual model based on a normative dataset of adult skulls.

A technique for intraoperative creation of patient-specific titanium mesh implants.

Prefabricated, patient-specific alloplastic implants for cranioplasty reduce surgical complexity, decrease operative times, minimize exposure and risk of contamination, and have resulted in improved aesthetic results. However, in creating a prefabricated custom implant using a patient's computed tomography data, a stable, unalterable defect must be clearly defined before surgery. In the event that an intraoperative modification of an exiting skull defect is required, or in cases of tumour resection in which the size of the skull defect is unknown preoperatively, these prefabricated implants cannot be used.

Teaching facial fracture repair: A novel method of surgical skills training using three-dimensional biomodels.

Background: The facial fracture biomodel is a three-dimensional physical prototype of an actual facial fracture. The biomodel can be used as a novel teaching tool to facilitate technical skills training in fracture reduction and fixation, but more importantly, can help develop diagnostic and management competence.

Objective: To introduce the 'facial fracture biomodel' as a teaching aid, and to provide preliminary evidence of its effectiveness in teaching residents the principles of panfacial fracture repair.

The potential role of an expert computer system to augment the opportunistic detection of individuals with familial hypercholesterolaemia from a community laboratory.

Background: Familial hypercholesterolaemia (FH) is the most common monogenic cause of premature atherosclerotic cardiovascular disease (CVD). However, most individuals with FH remain undiagnosed. We sought to determine if an expert system (ES) at a community laboratory could identify information relevant for estimating an individual's likelihood of FH using the Dutch Lipid Clinic Network criteria (DLCNC).

Stressing the recurrent laryngeal nerve during thyroidectomy.

Background: In thyroidectomy, little has been reported on the differential recurrent laryngeal nerve (RLN) palsy rates between the left and right sides. Even less is known about the potential differences causing these differential rates. This study reports the left versus right RLN palsy rates of total thyroidectomy cases in a single institution, relating them to the comparative stiffness of the left and right porcine RLNs.

Complete canthi removal reveals that forces from the amnioserosa alone are sufficient to drive dorsal closure in Drosophila.

Drosophila's dorsal closure provides an excellent model system with which to analyze biomechanical processes during morphogenesis. During native closure, the amnioserosa, flanked by two lateral epidermal sheets, forms an eye-shaped opening with canthi at each corner. The dynamics of amnioserosa cells and actomyosin purse strings in the leading edges of epidermal cells promote closure, whereas the bulk of the lateral epidermis opposes closure.

New engineering treatment of bovine pericardium confers outstanding resistance to calcification in mitral and pulmonary implantations in a juvenile sheep model.

Objective: To conduct a test of noninferiority for CardioCel (Admedus, Brisbane, Australia), a chemically engineered bovine pericardium over autologous pericardium treated intraoperatively with glutaraldehyde in a chronic juvenile sheep model of pulmonary valve (PV) and mitral valve (MV) reconstruction.

Methods: We replaced the posterior leaflet of the MV and of 1 PV cusp with patches in ewes aged 10 months. There were 2 groups: CardioCel (n = 6) and control (n = 4).