Cortical bone continuum damage mechanics constitutive model with stress triaxiality criterion to predict fracture initiation and pattern.

A primary objective of finite element human body models (HBMs) is to predict response and injury risk in impact scenarios, including cortical bone fracture initiation, fracture pattern, and the potential to simulate post-fracture injury to underlying soft tissues. Current HBMs have been challenged to predict the onset of failure and bone fracture patterns owing to the use of simplified failure criteria. In the present study, a continuum damage mechanics (CDM) model, incorporating observed mechanical response (orthotropy, asymmetry, damage), was coupled to a novel phenomenological effective strain fracture criterion based on stress triaxiality and investigated to predict cortical bone response under different modes of loading.

Importance of asymmetry and anisotropy in predicting cortical bone response and fracture using human body model femur in three-point bending and axial rotation.

Modeling of cortical bone response and failure is critical for the prediction of Crash Induced Injuries (CII) using advanced finite element (FE) Human Body Models (HBM). Although cortical bone is anisotropic and asymmetric in tension and compression, current HBM often utilize simple isotropic, symmetric, elastic-plastic constitutive models. In this study, a 50th percentile male femur FE model was used to quantify the effect of asymmetry and anisotropy in three-point bending and axial torsion.

Schizophrenia and anaesthesia.

Administering anaesthesia for elderly patients with chronic schizophrenia has always been a great challenge to anaesthetists. These patients will usually be on multiple antipsychotic drugs for many years and may lead to delayed awakening, cardiovascular instability, arrhythmias and sudden cardiac death during general anaesthesia. This case report is about the perioperative anaesthetic management of an elderly schizophrenic patient undergoing removal of femur implant.

Genetic polymorphisms of alcohol-metabolizing enzymes and their association with alcoholism risk, personality and anthropometric traits among Malaysian university students.

Three single nucleotide polymorphisms (SNPs) in alcohol-metabolizing genes - ADH1B (Arg47His), ADH1C (Ile350Val) and ALDH2 (Glu504Lys) have been extensively associated with flush reaction and alcoholism. Therefore, we investigated the association of these three SNPs with alcohol-induced reactions (AIRs), alcoholism risk, personality and anthropometric traits among Malaysian university students. AIRs, Self-Rating of the Effects of Alcohol (SRE) and Ten-Item Personality were surveyed, anthropometric measurements and DNA samples were taken.

Human mulipotential mesenchymal/stromal stem cells are derived from a discrete subpopulation of STRO-1bright/CD34 /CD45(-)/glycophorin-A-bone marrow cells.

Magnetic and flow cytometry-based methods were used to characterize clonogenic stromal cells in human bone marrow. STRO-1(bright) stromal cells were found to lack expression of CD34, CD45 and glycophorin-A markers associated with hematopoietic progenitor cells. These studies support the view that these are two distinct stem cell compartments in adult bone marrow.

Multipotential human adipose-derived stromal stem cells exhibit a perivascular phenotype in vitro and in vivo.

Mesenchymal stem-like cells identified in different tissues reside in a perivascular niche. In the present study, we investigated the putative niche of adipose-derived stromal/stem cells (ASCs) using markers, associated with mesenchymal and perivascular cells, including STRO-1, CD146, and 3G5. Immunofluorescence staining of human adipose tissue sections, revealed that STRO-1 and 3G5 co-localized with CD146 to the perivascular regions of blood vessels.

Bone morphogenetic protein 4 contributes to the maintenance of primitive cord blood hematopoietic progenitors in an ex vivo stroma-noncontact co-culture system.

Establishment of conditions supporting hematopoietic stem cell (HSC) maintenance and expansion ex vivo is critical for wider clinical application of cord blood (CB) transplantation. AFT024 is a murine fetal liver cell line that expands primitive hematopoietic cells via a process that is not understood. Here we show that bone morphogenic protein 4 (BMP4) is produced by AFT024 and contributes significantly to the maintenance of co-cultured CB-derived primitive cells.