Potential sexual transmission of Trypanosoma cruzi in mice.

Infection with the protozoan parasite Trypanosoma cruzi, the etiologic agent of human Chagas disease, results in life-long infection. Infective trypomastigotes circulate in the bloodstream and have the capacity to infect any cell type, including reproductive tissue. This study sought to assess the potential for sexual transmission of T.

Biomechanical properties and histology of db/db diabetic mouse Achilles tendon.

Foot ulcers are a severe complication of diabetic patients resulting from nerve and tendon pathologic alterations. In diabetic patients the tendons are thicker, shorter and have increased stiffness. We examined C57BL/KsJ (BKS.

Soft-tissue allografts terminally sterilized with an electron beam are biomechanically equivalent to aseptic, nonsterilized tendons.

Background: Allograft safety is contingent on effective sterilization. However, current sterilization methods have been associated with decreased biomechanical strength and higher failure rates of soft-tissue allografts. In this study, electron beam (e-beam) sterilization was explored as an alternative sterilization method to preserve biomechanical integrity.

Osteoinductivity of demineralized bone matrix is independent of donor bisphosphonate use.

Background: Demineralized bone matrix is commonly used as a bone graft substitute, either alone or to supplement an osteoconductive material, because of its osteoinductive properties. The aging of the population has led to an increase in the number of prospective donors of demineralized bone matrix who have taken bisphosphonates to prevent osteoclast-mediated bone resorption. The aim of this study was to determine whether oral bisphosphonate usage affects the osteoinductivity of demineralized bone matrix from donors.

Repeated freeze-thaw cycles do not alter the biomechanical properties of fibular allograft bone.

Background: Allograft tissues can undergo several freeze-thaw cycles between donor tissue recovery and final use by surgeons. However, there are currently no standards indicating the number of reasonable freeze-thaw cycles for allograft bone and it is unclear how much a graft may be degraded with multiple cycles.

Questions/purposes: We therefore asked whether (1) the mechanical properties of fibular allograft bone would remain unchanged with increasing numbers of freeze-thaw cycles and (2) histologic alterations from increased numbers of freeze-thaw cycles would correspond to any mechanical changes.

Demineralization removes residual alendronate in allograft bone procured from donors with a history of bisphosphonate use.

Background: Bisphosphonate-associated osteonecrosis (BON) of the jaw is a growing concern in the dental community, but the possible presence of residual bisphosphonates in demineralized allograft bone from bisphosphonate-using tissue donors and the clinical implications of using such bone are unclear. The objectives of this study are to determine whether alendronate remained in demineralized bone matrix (DBM) procured from donors with a documented history of oral bisphosphonate use and to examine whether the demineralization process removes alendronate from allograft bone.

Methods: A gas chromatography?mass spectrometry method was developed and validated to quantify residual alendronate in allograft bone.

Human peritoneal membrane reduces the formation of intra-abdominal adhesions in ventral hernia repair: experimental study in a chronic hernia rat model.

Background: Adhesions leading to intestinal obstructions and fistulae are severe complications related to the intraperitoneal placement of synthetic meshes. This study evaluated the efficacy of human peritoneal membrane (HPM) in a chronic hernia repair rat model as an anti-adhesive solution for preventing the development of intra-abdominal adhesions.

Materials And Methods: The mechanical properties of HPM and human fascia lata (HFL) were evaluated prior to in vivo implantation.

Human peritoneal membrane controls adhesion formation and host tissue response following intra-abdominal placement in a porcine model.

Background: Even with the advent of bioresorbable barriers, complications due to visceral adhesions following surgery continue to occur. The use of a homologous adhesive barrier such as human peritoneal membrane (HPM) could prevent adhesions formation and enhance wound healing. This study evaluates HPM as an effective adhesive barrier in a porcine model simulating a ventral hernia procedure.

Biomechanical and biologic effects of meniscus stabilization using triglycidyl amine.

The susceptibility of meniscus allografts to enzymatic degradation may be reduced through tissue stabilization. We have previously reported on an epoxide-based crosslinker, triglycidyl amine (TGA), which can be used alone or with a bisphosphonate (MABP) to stabilize heterograft heart valves and reduce their pathologic calcification. Our objective was to evaluate the effects of TGA and TGA-MABP pretreatment on an orthopedic allograft involving meniscus crosslinking, degradation, calcification, and compressive properties.

Tensile stimulation of murine stem cell-collagen sponge constructs increases collagen type I gene expression and linear stiffness.

The objectives of this study were to determine how tensile stimulation delivered up to 14 days in culture influenced type I collagen gene expression in stem cells cultured in collagen sponges, and to establish if gene expression, measured using a fluorescence method, correlates with an established method, real-time quantitative reverse transcriptase polymerase chain reaction (qRT-PCR). Using a novel model system, mesenchymal stem cells were harvested from six double transgenic mice in which the type I and type II collagen promoters were linked to green fluorescent protein-topaz and enhanced cyan fluorescent protein, respectively. Tissue-engineered constructs were created by seeding 0.

Using functional tissue engineering and bioreactors to mechanically stimulate tissue-engineered constructs.

Bioreactors precondition tissue-engineered constructs (TECs) to improve integrity and hopefully repair. In this paper, we use functional tissue engineering to suggest criteria for preconditioning TECs. Bioreactors should (1) control environment during mechanical stimulation; (2) stimulate multiple constructs with identical or individual waveforms; (3) deliver precise displacements, including those that mimic in vivo activities of daily living (ADLs); and (4) adjust displacement patterns based on reaction loads and biological activity.

Meniscal material properties are minimally affected by matrix stabilization using glutaraldehyde and glycation with ribose.

Knee meniscus replacement holds promise, but current allografts are susceptible to biodegradation. Matrix stabilization with glutaraldehyde, a crosslinking agent used clinically to fabricate cardiovascular bioprostheses, or with glycation, a process of crosslinking collagen with sugars such as ribose, is a potential means of rendering tissue resistant to such degradation. However, stabilization should not significantly alter meniscal material properties, which could disturb normal function in the knee.

Structural and mechanical properties of the glenohumeral joint posterior capsule.

The purpose of this study was to quantify regional variations in material properties of the glenohumeral joint posterior capsule and to compare these data with the anterior band of the inferior glenohumeral ligament (AB-IGHL). Mechanical properties were determined for individual bands of the AB-IGHL, superior posterior capsule (SUP-PC), middle posterior capsule (MID-PC), and inferior posterior capsule (INF-PC). Significant differences in tissue thickness were found among the 3 posterior capsular regions and the AB-IGHL.

Functional tissue engineering parameters toward designing repair and replacement strategies.

Abnormal joint kinematics and loads induced after soft tissue injuries are assumed to contribute to long-term degenerative joint disease and osteoarthritis. Controlling abnormal kinematics after repair and reconstruction of these injured structures would seem to be important for limiting wear of the articular cartilage surfaces. In this paper, we propose to expand the paradigm of functional tissue engineering to more fully characterize normal joint function and to establish design parameters for soft tissue repair and reconstruction to ultimately protect joint surfaces after surgery.

Effects of matrix stabilization when using glutaraldehyde on the material properties of porcine meniscus.

Meniscus transplantation frequently is one of the only options available for treating symptomatic younger patients with tibiofemoral pain and early arthrosis after a prior meniscectomy. However, clinical results indicate that current meniscal allografts may undergo degenerative changes due to enzymatic degradation during the remodeling phase. The objective of this study was to evaluate the effects of glutaraldehyde-induced matrix stabilization on the material properties of porcine meniscus prior to surgical implantation.