Recent Patents on Biomedical Engineering (v.3, #3)

Open Surgical Fixation of Fractured Ribs by Silvana F. Marasco (123-128).
Rib fractures are a painful and potentially disabling injury. The most severe manifestation, flail chest, is a potentially life threatening injury which can lead to respiratory failure. Two prospective randomised trials have shown a clear benefit of operative stabilisation of fractured ribs in flail chest patients in terms of short term hospital outcomes and longer term quality of life measures. However, despite the available evidence for benefits achieved by operative stabilization of flail chest, it has not become standard management. The reasons appear to be lack of consensus as to the particular injuries that require intervention, how the ribs should be fixed and what devices should be used. In fact, currently, there are no commercially available prostheses that have been designed specifically for rib fixation. This paper reviews the current evidence for operative fixation of fractured ribs and the available prostheses. Emphasis is given to the newer prostheses under development which are specific for rib fixation. Most of these have not reached clinical testing but have reported bench-testing results. There are a number of patents pending with interesting novel designs which could potentially revolutionise this surgical field.

Chitosan: A Versatile Biomedical Polymer by Zhanwu Cui, Lakshmi S. Nair (129-137).
Chitosan is a cationic polysaccharide derived from Chitin, a renewable natural polymer second in abundance to cellulose. Chitosan is one of the most preferred biomaterials for developing wound dressings, tissue engineering scaffolds and drug delivery vehicles due to its mucoadhesivity, hemostatic and wound healing properties. The versatility of chitosan lies in its chemical reactivity, which allows the development of wide range of chitosan derivatives with varied physical, chemical and biological properties. In short, chitosan is currently being considered for a variety of biomedical applications due to its excellent biocompatibility, biodegradability and bioactivities. This review covers the recent findings and patents on the biomedical applications of chitosan and chitosan derivatives.

Whole-Cell Biosensors: Research and Patents by Marcelo R. Fernandez, Delia L. Bernik (138-146).
In the last ten years several research articles and patents related to the obtaining and uses of whole-cell biosensors (WCB) have been published. Whole-cell sensors, whole-cell biosensors, chemical sensors, integrated sensors and bioreporters (among others) are the main terms used to define a living cell machinery adapted to detect target analytes at low concentration levels. The methods for constructing and detection technologies for these WCB could be very diverse. Some of them include a foreign nucleic acid sequence to act as reporter, to regulate the reporter's expression or both. But some other inventors exploit the natural properties of organisms without the need of genetic engineering. Another aspect is the localization of the cell at the moment of use. Some inventors, depending on the method of detection, need cells in a special location, such as the surface of a detector, entrapped in a matrix, or in the bulk of the sample. This review intends to compile the most relevant patents related to WCB which enable to illustrate the above mentioned cases of these new types of biosensors.

Recent Advances and Patents on Coronary Sinus Perfusion Devices for Treatment of Heart Disease by Mariko Kobayashi, Sharif Al-Ruzzeh, Jose L. Navia, Kiyotaka Fukamachi (147-152).
The concepts of arterialization of the coronary venous system and retrograde coronary sinus (CS) perfusion in clinical and experimental studies have inspired novel devices aiming for myocardial preservation and function improvement, especially in ischemic hearts. Based on these concepts, several patented devices using the CS have been developed to improve cardiac function in patients with heart disease. There are three main types of CS perfusion devices: the arterial- CS (A-CS) shunt, left ventricle-CS (LV-CS) shunt, and pressure-controlled CS occlusion device. In addition, catheters are used for drug delivery into the CS. Most of these devices are implanted percutaneously or by means of minimally invasive surgery. By avoiding the need for cardiopulmonary bypass, these devices offer a competitive treatment option for heart disease. This article reviews some CS devices in terms of methods of use and therapeutic concepts.

Four decades have passed since the first recombinant protein, somatostatin, was produced in Escherichia coli. To date, more than 160 biopharmaceuticals gained medical approval. As there is an increasing demand for new protein-based biopharmaceuticals and proteins used in diagnostics, novel or improved host organisms and expression systems are constantly being developed. Nevertheless, E. coli is still one of the most commonly used organisms for the production of recombinant therapeutic proteins. Despite many improvements of E. coli expression system, one major setback is protein aggregation and inclusion bodies (IBs) formation. These often cannot be prevented from forming during recombinant protein production. For a long time IB formation represented a problem in protein production. However, recent studies on bacterial cultivation and protein aggregation revealed that friendlier bacterial cultivation leads to production of non-classical IBs (ncIBs), which are composed of properly folded and biologically active proteins. Such active ncIBs can be used either for protein isolation (production) or as active nanoparticles. Since the field of nanobiotechnology is evolving fast, a further development of the use of active IBs is expected.

Reconstructive surgery is performed on abnormal or damaged soft tissues, caused by trauma, burns, congenital defects, tumours or disease. Damage to the underlying fatty tissues results in scar tissue formation and deformity, as well as the potential for reduced mobility if the injury occurs near a joint. The general aim in the clinic is to rebuild the affected tissues, and by doing so, to recover or improve function. Relevant clinical procedures include the revision of scar tissue from burns or trauma, laceration repair, the reconstruction of the breast after mastectomy or lumpectomy, and the restoration of the normal body structure following the removal of sarcomas or skin cancers. Since adipose tissue comprises the bulk of the adult tissues treated in these reconstructive approaches, the importance of vascularized fat in the field of plastic and reconstructive surgery is well established. Soft tissue engineering holds great promise for the improvement of standard reconstructive methodologies. In this context, two main approaches have arisen, which can be employed individually or in combination: (i) cell-based therapies and (ii) biologically compatible tissue scaffolds. This review provides a brief description of recent patents and findings in soft tissue regeneration for plastic and reconstructive surgery.

Recent Advances in Cartilage Regenerative Technologies by J. W. Freeman, L. D. Wright, B. L. Taylor (173-182).
Articular cartilage is a connective tissue designed to bear loads and provide smooth movement during joint articulation. Repeated loading and unloading typically leads to deterioration of articular cartilage, a condition known as osteoarthritis. Unfortunately, cartilage is avascular and osteoarthritis patients with relief from the pain and discomfort associated with this disease. Current treatments have achieved a level of success, but still have some limitations. Researchers have begun to enhance current treatment options and develop new modalities in order to heal or replace tissue damaged by osteoarthritis. These options include cell therapies, the use of hormones and other chemical factors, and improved joint replacements. This patent review presents background on the cartilage, current treatments for osteoarthritis, and new approaches utilizing a variety of techniques.

Patent Selections: by Bentham Science Publishers (183-184).
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 medical imaging, bioinformatics, image processing, biomaterials, pharmaceutical drugs, bioengineering, medical devices, design, biological devices, biomechanics and diagnostic devices related to biomedical engineering.