Recent Patents on Biomedical Engineering (v.5, #2)

An Introduction to Hardware and Methods for Biopotential Measurements: A Review by Adriano S. Vale-Cardoso, Mariana Geny Moreira, Homero N. Guimaraes (105-113).
Biopotentials are voltage signals collected at animal's or human's body surface which supply information about nerves, muscles and organs functionalities. Several kinds of biopotential, regarding the functionality of different parts of the organism, are commonly monitored in order to identify pathologies or abnormalities. Electrocardiogram, electroencephalogram and electromyogram are examples of biopotentials. A review of the challenges and often adopted solutions for biopotential measurements is presented, and also, some important related patents. The sources of interference are discussed individually as the known methods to reduce them. Some hardware parts are also analyzed, turning this review into a good starting point to deal with biopotential measurement and recording.

Transcatheter Aortic Valve Technology: Current State by Ernest Y. Young, Kiyotaka Fukamachi (114-121).
The percutaneous delivery of artificial heart valves via catheter has in the past few years, received widespread attention due to its regulatory approval in Europe and now in the United States as well as its proposed reduction of surgery related morbidity and mortality. This review describes the patents of the currently approved transcatheter aortic valves, as well as the patents of their important accessory valvular components. This review also summarizes the clinical work and outcomes for several of these devices.

Recent Patents on Cell-based Approaches for Intervertebral Disc Regeneration by In-Bo Han, Soo-Woo Kim, Alexander E. Ropper, Devang Thakor, Serdar Kabatas, Yang D. Teng (122-130).
Intervertebral disc (IVD) degeneration is a major cause of clinical back pain and thus has a significant clinical impact on life quality of humans. The associated poor intrinsic regeneration capacity of the IVD, due to low cell density, avascular nature of the extracellular matrix (ECM), lack of the lymphatic vessels or innervation leads to an increased susceptibility of IVD to degenerative pathology. During disc degeneration, dehydration of the nucleus pulposus (NP), resulting from loss of proteoglycans and disorganization of the ECM causes an inefficient transfer of load between vertebral bodies triggering further degeneration or even to damage of the annulus fibrosus. Standard treatments focus on removal of the pathological disc tissue combined with spinal fusion. Aside from the high cost of these procedures, it is well known that these surgical treatments currently do not carry ideal efficacy, with post-procedure patients frequently showing recurrent back pain due to possible acceleration of disc degeneration adjacent to fused segments. Therefore there is a growing interest in the transplantation of stem cells for regeneration of the degenerated IVD. The cell-based approach is wideranging, including delivery of exogenous growth factors, introduction of therapeutic genes, co-transplantation of different cell types, and implantation of cell-scaffold composite for tissue and/or chemical engineering purposes. In this review we describe recent patents on cell-based therapy as well as other biological therapies targeting prevention and treatment of IVD degeneration.

Cell cultivation is a promising remedy for damages of organism tissues. Since the experiments with cells in vivo are very complicated, many researchers are directing their efforts toward cultivation of cells in vitro to avoid this complexity. To achieve this goal, bioreactors are necessary to create the proper situation for cultivation of cells. One of the main requirements for such bioreactors is the ability to create stimulation of the cells. In this paper a number of the US patents and application for patents are reviewed with the emphasis on design and actuation methods. The review shows that three different approaches are mostly used for stimulation and actuation of bioreactors: mechanical, hydraulic and electromagnetic. In this article the core ideas of patents are studied and briefly explained by using illustration. At the end of the article, bioreactors which are developed by the authors are introduced.

Recent Patents in Bone Graft Substitute for Bone, Tendon, and Ligament Reconstruction by MaCalus V. Hogan, James N. Irvine, Richard Ma, Roshan James, Saadiq F. El-Amin, Quanjun Cui (142-147).
Treatment of large bone defects poses a real challenge to the orthopaedic surgeon. The surgeon often times calls on creativity in the form of bone graft substitutes to help mend large bone defects. The bone graft substitutes used today include inorganic compounds such as calcium phosphate, osteoconductive composites which act as a scaffold to allow for new bone growth, and some may include osteoinductive proteins which provide signals to the microenvironment promoting osteogenesis. Autologous bone grafts are still the gold standard and this creates a risk of harvest site morbidity and the defect may be too large for autologous bone alone. Injuries requiring tendon or ligament reconstruction rely upon the use of bone blocks in the form of bone-tendon-bone grafts, which can also create a hurdle for the orthopaedist. We have reviewed the current literature and recent patents available on bone graft substitutes and bone blocks for bonetendon- bone grafts and have described new biomaterials and therapeutics available to the orthopaedic surgeon.

Thermosensitive Liposomes in Cancer Therapy by Jonathan P. May, Shyh-Dar Li (148-158).
Thermosensitive liposomes have been a popular area of investigation for several years leading to a plentitude of scientific literature and several patents. The majority of formulations are still in the early stage of development and preclinical testing, although one formulation, ThermoDoxand#174;, is significantly more advanced. This formulation is now in clinical trials for a few different cancer indications. In this review, key patents and publications through the evolution of thermosensitive lipososomes are presented, including the use of polymers, lipids and other molecules to control the temperature sensitivity. ThermoDoxand#174; is discussed with an update on recent experiments and reports from the clinical trials. Finally, a summary of recent formulations designed to improve upon the ThermoDoxand#174; benchmark is presented, and the challenges and future directions for thermosensitive liposome technology are discussed.

Dendrimers have found extensive convention in varied fields of biomedical engineering. Particularly, polyamidoamine (PAMAM) dendrimers have been found to have unique properties, and also interesting researches in the field of biomedical engineering have been recognized, when compared to other class of dendrimers. PAMAM dendrimers are biofriendly synthetic substances, and broadly studied dendrimers for biomedical applications, especially as therapeutic compositions. The focus of this review (citing 188 references) is on PAMAM dendrimer developments for biomedical applications, with prominence on conjugations for their extensive applications in the field of biomedical engineering and comparisons between classical (Tomalia PAMAM dendrimers) and novel (Baker-Huang PAMAM dendrimers) PAMAM dendrimers are also discussed by covering recent patents on PAMAM dendrimers. Finally, the use of PAMAM dendrimers in the field of proteomics, especially for use in phosphopeptide enrichment is presented. The future work points at the promises of developments.

Review on Digital Breast Tomosynthesis Patents by Matos Monteiro, Joao, Santos Ribeiro, Andre, Lacerda, Luis (175-182).
Recent progress in breast imaging has led to new, improved techniques. Mammography is one of the most widely used breast cancer diagnosis technique as it allows visualization of breast lumps and calcifications before they are palpable. Nonetheless, it has some limitations, including structural overlap, because a mammogram is a 2D image of a 3D structure. Techniques based on 3D-reconstruction of breast images, such as digital breast tomosynthesis (DBT), are of great importance. DBT solves many tissue overlapping problems, which are a major source of recalls, and improves structure visualization through combination with mammography exams. Currently, DBT devices that have been patented use an X-Ray tube moving along an arc in order to capture a plurality of radiographic projections of the subject at different angle. Recently, parallel imaging configurations for breast tomosynthesis began to appear too. Techniques using multiple X-Ray anodes and/or cathodes are being developed so that mechanical instability can be greatly reduced. Despite its advantages, some considerations in the design of DBT systems are required. Such as the need to find better approaches regarding systems with less image blurring, lower acquisition times, lower patient dose and invulnerability to motion of the X-Ray source during acquisition.

Patent Selections by Bentham Science Publishers (183-186).
The patents annotated in this section have been selected from various patent databases. These recent patents are relevant to the articles published in this journal issue, categorized by different nanotechnology methods, processes and techniques involved.....