Devices formed of or including biocompatible polyhydroxyalkanoates are provided with controlled degradation rates, preferably less than one year under physiological conditions. Preferred devices include sutures, suture fasteners, meniscus repair devices, rivets, tacks, staples, screws (including interference screws), bone plates and bone plating systems, surgical mesh, repair patches, slings, cardiovascular patches, orthopedic pins (including bone filling augmentation material), adhesion barriers, stents, guided tissue repair/regeneration devices, articular cartilage repair devices, nerve guides, tendon repair devices, atrial septal defect repair devices, pericardial patches, bulking and filling agents, vein valves, bone marrow scaffolds, meniscus regeneration devices, ligament and tendon grafts, ocular cell implants, spinal fusion cages, skin substitutes, dural substitutes, bone graft substitutes, bone dowels, wound dressings, and hemostats. The polyhydroxyalkanoates can contain additives, be formed of mixtures of monomers or include pendant groups or modifications in their backbones, or can be chemically modified, all to alter the degradation rates. The polyhydroxyalkanoate compositions also provide favorable mechanical properties, biocompatibility, and degradation times within desirable time frames under physiological conditions.

Medical devices and applications of polyhydroxyalkanoate polymers

The present invention provides a device for occluding an anatomical aperture, such as an atrial septal defect (ASD) or a patent foramen ovale (PFO). The occluder includes two sides connected by a central tube. The occluder is formed from a tube, which is cut to produce struts in each side. Upon the application of force, the struts deform into loops. The loops may be of various shapes, sizes, and configurations, and, in at least some embodiments, the loops have rounded peripheries. In some embodiments, at least one of the sides includes a tissue scaffold. The occluder further includes a catch system that maintains its deployed state in vivo. When the occluder is deployed in vivo, the two sides are disposed on opposite sides of the septal tissue surrounding the aperture and the catch system is deployed so that the occluder exerts a compressive force on the septal tissue and closes the aperture.

Tubular patent foramen ovale (PFO) closure device with catch system

An expandable catheter (10) accommodates a medical device that is being removed from a body with a larger diameter than the catheter. The same catheter may be used to reposition a device within the body to an alternative delivery site. A catheter or sheath may be used to deliver a medical device, surgical instrument, or biological sample.

Expandable sheath tubing

A septal occluder, such as one made from a polymer tube, can have portions on either side of a patent foramen ovale (PFO) or other septal defect. The portions on either side can be held in place with a catching mechanism that can take one of many forms. The tube can be made of bioresorbable materials.

Catching mechanisms for tubular septal occluder

The present invention provides a device for occluding an anatomical aperture, such as a septal defect or patent foramen ovale (PFO). The occluder includes two sides connected by an intermediate joint. Each of the sides includes at least one elongate element, which is arranged to form non-overlapping loops. Each loop has at least one radially-extending segment that is adjacent to a radially-extending segment of another loop. In at least some embodiments, at least one pair of adjacent radially-extending segments is connected. The loops of the device may be of various shapes, sizes, and configurations, and, in at least some embodiments, the loops have rounded peripheries. In some embodiments, at least one of the sides includes a tissue scaffold. When the occluder is deployed in vivo, the two sides are disposed on opposite sides of the septal tissue surrounding the aperture, thereby exerting a compressive force on the septal tissue that is distributed along both the outer periphery of the occluder and the radially­extending segments.

Patent foramen ovale (PFO) closure device with radial and circumferential support

The gene encoding a 4-hydroxybutyryl-Co A transferase has been isolated from bacteria and integrated into the genome of bacteria also expressing a polyhydroxyalkanoate synthase, to yield an improved production process for 4HB-containing polyhydroxyalkanoates using transgenic organisms, including both bacteria and plants. The new pathways provide means for producing 4HB containing PHAs from cheap carbon sources such as sugars and fatty acids, in high yields, which are stable. Useful strains are obtaining by screening strains having integrated into their genomes a gene encoding a 4HB-CoA transferase and/or PHA synthase, for polymer production. Processes for polymer production use recombinant systems that can utilize cheap substrates. Systems are provided which can utilize amino acid degradation pathways, α-ketoglutarate, or succinate as substrate.

David P. Martin

Papers

Biological systems for manufacture of polyhydroxyalkanoate polymers containing 4-hydroxyacids