Biomedical subjects

A Peyser

Publications and source records attributed to A Peyser.

23 records · Page 2Linked to original sources

PubMedDate not supplied

Engineered human mesenchymal stem cells: a novel platform for skeletal cell mediated gene therapy.

BACKGROUND: Human mesenchymal stem cells (hMSCs) are pluripotent cells that can differentiate to various mesenchymal cell types. Recently, a method to isolate hMSCs from bone marrow and expand them in culture was described. Here we report on the use of hMSCs as a platform for gene therapy aimed at bone lesions. METHODS: Bone marrow derived hMSCs were expanded in culture and infected with recombinant adenoviral vector encoding the osteogenic factor, human BMP-2. The osteogenic potential of genetically engineered hMSCs was assessed in vitro and in vivo. RESULTS: Genetically engineered hMSCs displayed enhanced proliferation and osteogenic differentiation in culture. In vivo, transplanted genetically engineered hMSCs were able to engraft and form bone and cartilage in ectopic sites, and regenerate bone defects (non-union fractures) in mice radius bone. Importantly, the same results were obtained with hMSCs isolated from a patient suffering from osteoporosis. CONCLUSIONS: hMSCs represent a novel platform for skeletal gene therapy and the present results suggest that they can be genetically engineered to express desired therapeutic proteins inducing specific differentiation pathways. Moreover, hMSCs obtained from osteoporotic patients can restore their osteogenic activity following human BMP-2 gene transduction, an important finding in the future planning of gene therapy treatment for osteoporosis.

Adenoviridae↗

PubMedDate not supplied

Retrograde nailing of femoral fractures distal to previous osteosynthesis.

As the proportion of elderly in the population grows, the incidence of femoral fractures distal to previous proximal osteosynthesis is increasing. When the gap between two rigid load-bearing fixations consists of osteopenic bone, the risk of further fractures increases. Herein the authors describe a load-sharing device that stabilizes the fracture and eliminates the osteopenic gap, allowing early mobilization and rapid return to the preinjury level of activity.

Aged↗

PubMedDate not supplied

Equalization of lower limbs by epiphysiodesis: results of treatment.

Equalization of lower limb length was achieved by epiphysiodesis in 20 children. During the period under review the Phemister procedure was replaced by percutaneous epiphysiodesis, and orthoroentgenogram was superseded by computed tomography (CT) scanning. In five children with anisomelia, whose expected discrepancy was 4.5 cm, the results at maturity showed an average discrepancy of 0.7 cm. In 10 girls with limb-length discrepancy (LLD) caused by ischemic necrosis with congenital dislocation of the hip, the average LLD at maturity was 0.6, whereas the expected LLD was 4 cm. In five children with LLD caused by infection, the average discrepancy was 3.8 cm at the time of epiphysiodesis, whereas at maturity it was 0.5 cm. A good result was achieved in 90% of the patients. We recommend the Moseley straight-line graph, CT scanography, and percutaneous epiphysiodesis.

Adolescent↗

PubMedDate not supplied

Popliteal pterygium associated with complete amelia of upper limb: early surgical treatment.

We report a 5-year clinical follow-up and the operative details of a patient who was born with popliteal pterygium and ipsilateral upper amelia. There were no craniofacial, genitourinary, or other extremity abnormalities, other than severe pes equinovarus. At age 3 weeks, excision of the pterygium and partial release of the hind foot had accomplished a significant but incomplete release of the knee contracture. At age 11 months, a second release of the pterygium, combined with complete reconstruction of the foot, accomplished a straight limb. Presently at the age of 5, the boy has 40 degrees limitation to full extension at the knee but walks, runs, and behaves like all the other children in the nursery school. This combination of congenital malformations and early surgical intervention has never been described in the orthopedic literature.

Abnormalities, Multiple↗

PubMedDate not supplied

Technical complications of the tibiofibular syndesmotic screw.

Three patients with ankle fractures are presented to demonstrate poor results due to improper application of a syndesmotic screw. In these cases failure of surgical treatment caused accelerated disruption of the ankle mortise with cartilage wear, or instability and joint distraction. Simple internal fixation with a single screw requires strict awareness of the potential harm that can be inflicted on the joint. The syndesmotic screw has to be inserted with a proper understanding of the biomechanics of ankle joint structures.

Adult↗