Depression, quality of life, and medical resource utilization in sickle cell disease.

Sickle cell disease (SCD) is a chronic, debilitating disorder. Chronically ill patients are at risk for depression, which can affect health-related quality of life (HRQoL), health care utilization, and cost. We performed an analytic epidemiologic prospective study to determine the prevalence of depression in adult patients with SCD and its association with HRQoL and medical resource utilization.

A cross sectional analysis from a single institution's experience of psychosocial distress and health-related quality of life in the primary brain tumor population.

Primary brain tumor patients experience high levels of distress. The purpose of this cross-sectional, retrospective study is to evaluate the level and different sources of psychosocial distress and how these pertain to health-related quality of life (HRQoL). The Primary and Recurrent Glioma registry at Duke's The Preston Robert Tisch Brain Tumor Center was queried retrospectively for demographic and clinical information on patients seen between December 2013 and February 2014.

In situ crosslinking elastin-like polypeptide gels for application to articular cartilage repair in a goat osteochondral defect model.

The objective of this study was to evaluate an injectable, in situ crosslinkable elastin-like polypeptide (ELP) gel for application to cartilage matrix repair in critically sized defects in goat knees. One cylindrical, osteochondral defect in each of seven animals was filled with an aqueous solution of ELP and a biocompatible, chemical crosslinker, while the contralateral defect remained unfilled and served as an internal control. Joints were sacrificed at 3 (n = 3) or 6 (n = 4) months for MRI, histological, and gross evaluation of features of biomaterial performance, including integration, cellular infiltration, surrounding matrix quality, and new matrix in the defect.

Early-onset degeneration of the intervertebral disc and vertebral end plate in mice deficient in type IX collagen.

Objective: Type IX collagen is an important component of the intervertebral disc extracellular matrix. Mutations in type IX collagen are associated with premature disc degeneration in mice and a predisposition to disc disorders in humans. The aim of this study was to assess the prevalence and timeline of intervertebral disc degeneration in mice homozygous for an inactivated Col9a1 gene.

Pathogenesis of osteoarthritis-like changes in the joints of mice deficient in type IX collagen.

Objective: To examine the pathogenetic mechanisms of osteoarthritis (OA)-like changes in Col9a1-/- mice, which are deficient in type IX collagen.

Methods: Knee joints and temporomandibular joints (TMJs) from Col9a1-/- mice and their wild-type (Col9a1+/+) littermates were examined by light microscopy. Immunohistochemical staining was performed to examine the expression of matrix metalloproteinase 3 (MMP-3) and MMP-13, degraded type II collagen, and the discoidin domain receptor 2 (DDR-2) in knee joints.

Ascorbic acid increases the severity of spontaneous knee osteoarthritis in a guinea pig model.

Objective: To determine whether ascorbic acid might be of benefit for the treatment of spontaneous osteoarthritis (OA) when administered over a long period of time.

Methods: We investigated the effects of 8 months' exposure to low, medium, and high doses of ascorbic acid on the in vivo development of histologic knee OA in the male Hartley guinea pig. The low dose represented the minimum amount needed to prevent scurvy.

Cartilage mechanics in the guinea pig model of osteoarthritis studied with an osmotic loading method.

Objective: To determine the material properties of articular cartilage in the Hartley guinea pig model of spontaneous osteoarthritis.

Methods: Cartilage-bone samples from the medial femoral condyle and tibial plateau of 12 month-old guinea pig knees were subjected to osmotic loading. Site-matched swelling strains and fixed charge density values were used in a triphasic theoretical model for cartilage swelling to determine the modulus of the cartilage solid matrix.

Osteoarthritis-like changes and decreased mechanical function of articular cartilage in the joints of mice with the chondrodysplasia gene (cho).

Objective: To investigate whether heterozygosity for a loss-of-function mutation in the gene encoding the alpha1 chain of type XI collagen (Col11a1) in mice (chondrodysplasia, cho) causes osteoarthritis (OA), and to understand the biochemical and biomechanical effects of this mutation on articular cartilage in knee and temporomandibular (TM) joints.

Methods: Articular cartilage from the knee and TM joints of mice heterozygous for cho (cho/+) and their wild-type littermates (+/+) was examined. The morphologic properties of cartilage were evaluated, and collagen fibrils were examined by transmission electron microscopy.

Osmotic loading to determine the intrinsic material properties of guinea pig knee cartilage.

Few methods exist to study cartilage mechanics in small animal joints due to the difficulties associated with handling small tissue samples. In this study, we apply an osmotic loading method to quantify the intrinsic material properties of articular cartilage in small animal joints. Cartilage samples were studied from the femoral condyle and tibial plateau of two-month old guinea pigs.

Development of tensile strength during distraction osteogenesis in a rat model.

These studies were designed to determine the reliability of in vitro tensile testing to measure the temporal development of regenerate bone strength in rats during limb lengthening (distraction osteogenesis, DO). External fixators were placed on the right tibiae of 36 virus-free, 400-450 g male Sprague Dawley rats, and osteotomies (n = 33) were performed. Distraction was initiated the following morning (0 day latency) at 0.

An algorithm to optimize perioperative blood management in surgery.

Innovation in surgical blood management has been fueled by patients' perceptions of the risks associated with allogeneic blood transfusions and by surgeons' attitudes toward the use of allogeneic blood. The challenge is to determine the best blood management strategy to implement in the individual patient, particularly in patients with anemia who are at high risk of allogeneic blood transfusion. An algorithm to estimate safe blood loss based on individual patient parameters has been developed.

Analysis of a biodegradable composite for bone healing.

A degradable L-PLA/calcium carbonate composite made of interconnecting phases was examined. This structure was used both to slow the degradation rate and to reduce the brittleness of the ceramic. Both in vitro and in vivo degradation studies were performed.

Biomechanical comparison of reconstruction techniques in simulated lateral ankle ligament injury.

Eighteen intact ankles were loaded with inversion-eversion and anterior-posterior forces, and motions of the talus and calcaneus were measured. Ankles were tested in neutral, 15 degrees of dorsiflexion, and 15 degrees of plantar flexion. The anterior talofibular ligament was then sectioned and testing was repeated.

Simulated lateral ankle ligamentous injury. Change in ankle stability.

The effect of simulated ankle ligamentous injury on ankle-subtalar joint complex laxity was studied. Thirty-six intact ankles were loaded in inversion-eversion and anterior-posterior directions. Motions of the talus and calcaneus were measured with respect to the tibia.

Biomechanical analysis of patellar tendon allografts as a function of donor age.

We evaluated the biomechanical properties of patellar tendon allografts from donors aged 18 to 55 years. Bone-patellar tendon-bone complexes were harvested from acceptable donors and processed. Fat and soft tissue were removed, and the tendons were sectioned lengthwise leaving the central third.

Pullout strength of fixation screws from polymethylmethacrylate bone cement.

Polymethylmethacrylate bone cement is often used to fill voids and increase the strength of osteoporotic and pathological bone. However, it is unclear as to which method of cement augmentation provides optimal screw fixation. This study was conducted to determine which of the current cement augmentation techniques provides the strongest construct when used in association with orthopaedic fixation screws.

Initial stability of porous coated acetabular implants. The effect of screw placement, screw tightness, defect type, and oversize implants.

The effects of screw location, screw tightness, acetabular bony defects, and implant size on the initial stability of porous coated acetabular implants was studied in vitro using 12 fresh frozen cadaver pelves. The fixation of porous coated acetabular implants was compared following fixation with either rim or center screws. Implants were tested first under axial and torsional stress.

Retention and strength of silicone-rubber catheters. A report of five cases of retention and analysis of catheter strength.

Five patients had a silicone-rubber catheter that broke during attempted removal. Mechanical testing was performed to determine the tensile strength of silicone-rubber as well as of polyvinyl chloride catheters. Silicone-rubber catheters were found to have a low tensile strength.

A biomechanical evaluation of an intramedullary fixation device for intertrochanteric fractures.

The strength and stability of an intramedullary device when used to fix intertrochanteric fractures were determined and compared with the dynamic hip screw (DHS). A standard four-part osteotomy was created in eight paired fresh frozen human cadaver femurs. The intramedullary fixation device and a DHS were implanted in each pair member, and mechanical testing was performed.

Mechanical properties of fibrin adhesives for blood vessel anastomosis.

Various methods have been used for anastomosing, or attaching, two ends of a severed blood vessel together. The most common method, suturing, is tedious, can be time-consuming, and requires special training in microvascular surgery. Other methods, such as mechanical devices and lasers, have some problems as well.