Can Cadaver Testing Replicate In Vivo Kinematics of Total Knee Arthroplasty?

Introduction: Whether the kinematics of cadaveric knees recreate those of the patient's knees after total knee arthroplasty (TKA) remains unknown. This study compared in vivo and in vitro fluoroscopic kinematics of knees after TKA during knee bending using the same implant design.

Methods: Patients who had undergone cruciate-retaining and cruciate-substituting total knee arthroplasty (CR-TKA and CS-TKA) did squatting motions.

Comparison of in vivo kinematics of total knee arthroplasty between cruciate retaining and cruciate substituting insert.

Background: The decision to choose cruciate retaining (CR) insert or cruciate substituting (CS) insert during total knee arthroplasty (TKA) remains a controversial issue. We hypothesized that there are different knee kinematics between CR and CS inserts and that a raised anterior lip design would offer a potential minimization of the paradoxical movement and provide joint stability. The objective of this study was to evaluate and compare kinematics of a CR and CS TKA of the same single-radius design.

Patellar resurfacing has minimal impact on in vitro tibiofemoral kinematics during deep knee flexion in total knee arthroplasty.

Background: While patellar resurfacing can affect patellofemoral kinematics, the effect on tibiofemoral kinematics is unknown. We hypothesized that patellar resurfacing would affect tibiofemoral kinematics during deep knee flexion due to biomechanical alteration of the extensor mechanism.

Methods: We performed cruciate-retaining TKA in fresh-frozen human cadaveric knees (N = 5) and recorded fluoroscopic kinematics during deep knee flexion before and after the patellar resurfacing.

In vivo kinematic analysis of posterior-stabilized total knee arthroplasty for the valgus knee operated by the gap-balancing technique.

Background: Most in vivo kinematic studies of total knee arthroplasty (TKA) report on the varus knee. The objective of the present study was to evaluate in vivo kinematics of a posterior-stabilized fixed-bearing TKA operated on a valgus knee during knee bending in weight-bearing (WB) and non-weight-bearing (NWB).

Methods: A total of sixteen valgus knees in 12 cases that underwent TKA with Scorpio NRG PS knee prosthesis and that were operated on using the gap balancing technique were evaluated.

Effective expression and purification of bioactive recombinant soluble LIGHT.

LIGHT (TNFSF14, CD258) is a member of the tumor necrosis factor (TNF) ligand superfamily, which is involved in innate and adaptive immune responses as well as in regulation of cell survival and proliferation. LIGHT forms a membrane-anchored homotrimeric complex on the cell surface and is often processed as a soluble protein. In this study, we established an effective strategy for producing bioactive soluble forms of human LIGHT (s-hLIGHT), which is an extracellular region (Ile(84)-Val(240)) of human LIGHT (hLIGHT), and soluble forms of mouse LIGHT (s-mLIGHT), which is an extracellular region (Asp(72)-Val(239)) of mouse LIGHT (mLIGHT).

In vivo kinematics of three-component mobile-bearing total ankle replacement in rheumatoid ankle with talocalcaneal arthrodesis and spontaneous talocalcaneal fusion.

Objective: It is often that patients with rheumatoid arthritis (RA) who require ankle surgeries already have the degeneration of talocalcaneal joints. When talocalcaneal joint was fused, whether operatively or spontaneously, ankle kinematics would be affected. The purpose of this paper was to study in vivo kinematics of mobile-bearing total ankle replacement (TAR) in rheumatoid ankle with concomitant talocalcaneal arthrodesis or with preexisting spontaneous talocalcaneal fusion.

Significant effect of the posterior tibial slope on the weight-bearing, midflexion in vivo kinematics after cruciate-retaining total knee arthroplasty.

The purpose of the present study was to compare weight bearing (WB) and non-WB conditions, and to evaluate the effect of the posterior tibial slope (PTS) on the in vivo kinematics of 21 knees after posterior cruciate ligament-retaining total knee arthroplasty during midflexion using 2-dimensional/3-dimensional registration. During WB, medial pivot and bicondylar rollback were observed. During non-WB, both the medial and lateral condyles moved significantly more anteriorly as compared to the WB state.

Structural analysis of the mechanism of inhibition and allosteric activation of the kinase domain of HER2 protein.

Aberrant signaling of ErbB family members human epidermal growth factor 2 (HER2) and epidermal growth factor receptor (EGFR) is implicated in many human cancers, and HER2 expression is predictive of human disease recurrence and prognosis. Small molecule kinase inhibitors of EGFR and of both HER2 and EGFR have received approval for the treatment of cancer. We present the first high resolution crystal structure of the kinase domain of HER2 in complex with a selective inhibitor to understand protein activation, inhibition, and function at the molecular level.

Trimerization of murine TNF ligand family member LIGHT increases the cytotoxic activity against the FM3A mammary carcinoma cell line.

LIGHT is a member of the tumor necrosis factor ligand superfamily, which plays important roles in inflammatory and immune responses. LIGHT forms a membrane-anchored homotrimeric complex on the cell surface and is often processed as a soluble protein. Recombinant soluble human LIGHT produced by mammalian cells or Escherichia coli is functional at nanomolar concentrations.

Role of the liver in glucose homeostasis in PI 3-kinase p85alpha-deficient mice.

Phosphoinositide 3-kinase (PI3K) p85alpha-deficient mice exhibit hypoglycemia as a result of increased insulin sensitivity and glucose uptake in peripheral tissues. Although PI3K is central to the metabolic actions of insulin, its mechanism of action in liver is not well understood. In the present study, we investigated hepatic insulin signaling and glucose homeostasis in p85alpha-deficient and wild-type mice.