The thermal profile of self-tapping screws: The effect of insertion speed, power insertion, and screw geometry on heat production at the bone-screw interface.

Introduction: Power insertion of screws using high-speed saves time during operative fixation of fractures compared to manual insertion. Heat production during screw insertion may cause thermal damage at the critical bone-screw interface, reducing fixation strength, delaying healing, or increasing infection risk. Currently, the thermal impact of screw insertion is incompletely understood.

Temporal response of an injectable calcium phosphate material in a critical size defect.

Background: Calcium phosphate-based bone graft substitutes are used to facilitate healing in bony defects caused by trauma or created during surgery. Here, we present an injectable calcium phosphate-based bone void filler that has been purposefully formulated with hyaluronic acid to offer a longer working time for ease of injection into bony defects that are difficult to access during minimally invasive surgery.

Methods: The bone substitute material deliverability and physical properties were characterized, and in vivo response was evaluated in a critical size distal femur defect in skeletally mature rabbits to 26 weeks.

Fatigue implications for bending orthopaedic plates.

Objectives: - We aimed to investigate how pre-bending affects the mechanical properties, specifically fatigue, of stainless-steel plates.

Methods: - 3.5mm LCP 10-hole plates were pre-bent in 1, 2 and 3 locations to the same overall degree and fatigue testing performed.

Comparative osteoconductivity of bone void fillers with antibiotics in a critical size bone defect model.

The study aimed to evaluate the comparative osteoconductivity of three commercially available bone void fillers containing gentamicin with respect to new bone, growth, host tissue response and resorption of the implant material. Defects were created in the cancellous bone of the distal femur and proximal tibia of 12-skeletally mature sheep and filled with three commercially available bone void fillers containing gentamicin (Stimulan-G, Cerament-G, Herafill-G). Peripheral blood was taken pre-operatively and at the time of implantation, as well as at intermittent timepoints following surgery to determine systemic gentamicin levels (5-,15- and 30- minutes, 1, 2, 3, 6, 12, 24, 48- and 72-hours, 3-, 6- and 12-weeks).

The effect of surgery on patellar tendinopathy: Novel use of MRI questions the exploitability of the rat collagenase model to humans.

Background: patellar tendinopathy is an overuse condition most commonly affecting jumping athletes. Surgery is reserved for refractory cases; however, it lacks high level clinical evidence and basic science to support its use. The purpose of this study was to determine the biomechanical and histological response of surgical excision on patellar tendinopathy in the rat collagenase tendinopathy model and correlate MRI findings.

Effects of supercritical fluid CO and 25 kGy gamma irradiation on the initial mechanical properties and histological appearance of tendon allograft.

Tendon allografts, when autograft options are limited or when obtaining an autograft is not aligned with the patients' best interest, play an important role in tendon and ligament reconstruction. To minimize the risk of infectious disease transmission tissue banks perform screening tests and the allografts cleaned are sterilized. The current study examines and compares the initial mechanical properties and histological appearance of supercritical CO (SCCO)-treated and gamma-irradiated porcine extensor tendons.

Monoclonal Antibody Against Prolactin Receptor: A Randomized Placebo-Controlled Study Evaluating Safety, Tolerability, and Pharmacokinetics of Repeated Subcutaneous Administrations in Postmenopausal Women.

BAY 1158061 is a potent monoclonal prolactin (PRL) receptor antibody, blocking PRL receptor (PRLR)-mediated signaling in a noncompetitive manner, which was tested in a randomized, placebo-controlled multiple dose study in postmenopausal women. The objective was to investigate safety, tolerability, pharmacokinetic characteristics, and effects of BAY 1158061 on serum PRL level. The study consisted of 4 parallel groups receiving up to 3 subcutaneous (sc) administrations of BAY 1158061 or placebo in 2 different dosing regimens.

Glyoxalase 1 Modulation in Obesity and Diabetes.

Obesity and type 2 diabetes mellitus are increasing globally. There is also increasing associated complications, such as non-alcoholic fatty liver disease (NAFLD) and vascular complications of diabetes. There is currently no licensed treatment for NAFLD and no recent treatments for diabetic complications.

Effects of Sodium Glucose Cotransporter-2 Inhibitors on Serum Uric Acid in Type 2 Diabetes Mellitus.

Hyperuricemia has been linked to metabolic syndrome, cardiovascular disease, and chronic kidney disease. Hyperuricemia and type 2 diabetes mellitus were inter-related, type 2 diabetes mellitus was more at risk of having a higher serum uric acid level, and also individuals with higher serum uric acid had higher risk of developing type 2 diabetes in the future. Insulin resistance seems to play an important role in the causal relationship between metabolic syndrome, type 2 diabetes, and hyperuricemia.

Apical Microleakage in Root Canals Obturated With 2 Different Endodontic Sealer Systems in Canine Teeth of Dogs.

An apical dye leakage test was utilized to compare 2 endodontic sealer systems commonly used in veterinary endodontic treatment. Rotary instrumentation followed by injection of 2 different sealers (GuttaFlow 2 and AH Plus) and a single master cone obturation technique were compared. Following obturation and restoration, specimens were immersed in India ink for 48 hours.

Social Competence at Two Years after Childhood Traumatic Brain Injury.

Children with traumatic brain injury (TBI) are at risk for social impairment, but research has yet to document the trajectory of these skills post-injury and factors that may predict social problems. This study addressed these gaps in knowledge, reporting on findings from a prospective, longitudinal follow-up study that investigated social outcomes post-injury and explored factors contributing to these outcomes at two years post-injury. The sample included 113 children, 74 with TBI and 39 typically developing (TD) controls.

Does PEEK/HA Enhance Bone Formation Compared With PEEK in a Sheep Cervical Fusion Model?

Background: Polyetheretherketone (PEEK) has a wide range of clinical applications but does not directly bond to bone. Bulk incorporation of osteoconductive materials including hydroxyapatite (HA) into the PEEK matrix is a potential solution to address the formation of a fibrous tissue layer between PEEK and bone and has not been tested.

Questions/purposes: Using in vivo ovine animal models, we asked: (1) Does PEEK-HA improve cortical and cancellous bone ongrowth compared with PEEK? (2) Does PEEK-HA improve bone ongrowth and fusion outcome in a more challenging functional ovine cervical fusion model?

Methods: The in vivo responses of PEEK-HA Enhanced and PEEK-OPTIMA Natural were evaluated for bone ongrowth in the form of dowels implanted in the cancellous and cortical bone of adult sheep and examined at 4 and 12 weeks as well as interbody cervical fusion at 6, 12, and 26 weeks.

Transdermal fentanyl and its use in ovine surgery.

Fentanyl delivered via a transdermal patch has the potential to decrease the need for post-operative handling of sheep undergoing surgical procedures. Two studies were performed to test: (1) the ideal timing for the application of pre-emptive analgesic patches and (2) the efficacy of a 2 µg/kg/h dose, as extrapolated from other species. The first study had sheep divided into two groups.

Meniscal allograft sterilisation: effect on biomechanical and histological properties.

Sterilisation of allografts are a crucial step in ensuring safety and viability. Current sterilisation standards such as 25 kGy gamma irradiation (γ) can have adverse effects on the ultrastructure and biomechanical properties of allograft tissue. Supercritical CO2 (SCCO2) technology, represents an improved sterilisation process that potentially preserves tissue properties.

Frequency Modulated Translocational Oscillations of Nrf2 Mediate the Antioxidant Response Element Cytoprotective Transcriptional Response.

Aims: Stress responsive signaling coordinated by nuclear factor erythroid 2-related factor 2 (Nrf2) provides an adaptive response for protection of cells against toxic insults, oxidative stress and metabolic dysfunction. Nrf2 regulates a battery of protective genes by binding to regulatory antioxidant response elements (AREs). The aim of this study was to examine how Nrf2 signals cell stress status and regulates transcription to maintain homeostasis.

Synthetic polymers enable non-vitreous cellular cryopreservation by reducing ice crystal growth during thawing.

The cryopreservation of cells, tissue and organs is fundamental to modern biotechnology, transplantation medicine and chemical biology. The current state-of-the-art method of cryopreservation is the addition of large amounts of organic solvents such as glycerol or dimethyl sulfoxide, to promote vitrification and prevent ice formation. Here we employ a synthetic, biomimetic, polymer, which is capable of slowing the growth of ice crystals in a manner similar to antifreeze (glyco)proteins to enhance the cryopreservation of sheep and human red blood cells.

Lumbar spinal fusion with β-TCP granules and variable Escherichia coli-derived rhBMP-2 dose.

Background Context: The ideal tissue-engineered solution for any bone graft substitute is to assist in the rapid formation of bone and facilitate fusion.

Purpose: The present study aims to evaluate this E-BMP-2 (Escherichia coli-derived human bone morphogenetic protein-2) in ovine posterolateral lumbar fusion (PLF) to examine the influence of dose and overall performance in a model with similar graft size and diffusive challenges to the human.

Study Design/setting: In vivo large animal model study.

The effect of sterilization on the mechanical properties of intact rabbit humeri in three-point bending, four-point bending and torsion.

Load bearing bone allografts are used to replace the mechanical function of bone that has been removed or to augment bone that has been damaged in trauma. In order to minimize the risk of infection and immune response, the bone is delipidated and terminally sterilized prior to implantation. The optimal method for bone graft sterilization has been the topic of considerable research.

Genetic association study of CYP1A1 polymorphisms identifies risk haplotypes in nonsmall cell lung cancer.

Lung cancer remains a leading cause of disease globally, with smoking being the largest single cause. Phase I enzymes, including cytochrome P(450), family 1, subfamily A, polypeptide 1 (CYP1A1), are involved in the activation of carcinogens, such as polycyclic aromatic hydrocarbons, to reactive intermediates that are capable of binding covalently to DNA to form DNA adducts, potentially initiating the carcinogenic process. The aim of the present study was to investigate the association of CYP1A1 gene polymorphisms and haplotypes with lung cancer risk.

Posterolateral spinal fusion in a rabbit model using a collagen-mineral composite bone graft substitute.

Choosing the appropriate graft material to participate in the healing process in posterolateral spinal fusion continues to be a challenge. Combining synthetic graft materials with bone marrow aspirate (BMA) and autograft is a reasonable treatment option for surgeons to potentially reduce or replace the need for autograft. FormaGraft, a bone graft material comprising 12% bovine-derived collagen and 88% ceramic in the form of hydroxyapatite (HAp) and beta tricalcium phosphate (beta-TCP) was evaluated in three possible treatment modalities for posterior spinal fusion in a standard rabbit model.