Health, Medicine, & Biotechnology

Validating Requirements for Surgical Spinal Implants With Finite Element Analysis

Vertebral body replacement devices require thorough analysis and engineering testing to ensure their safety.

When Spinal USA, a manufacturer and distributor of advanced surgical spinal products, designed a new series of spinal implants called vertebral body replacement (VBR) devices, they needed to meet United States Food and Drug Administration (FDA) requirements for physical laboratory testing in order to obtain approval for use. Designed to be inserted by a surgeon into a patient’s spine during a spinal fusion procedure, the VBR devices required thorough engineering testing to ensure that they were safe and effective. In order to meet the FDA requirements, Spinal USA contracted Saba Metallurgical and Plant Engineering Services (SMPES) to perform finite element analysis (FEA) of the various VBR designs using ALGOR FEA software to virtually predict the behavior of the VBR designs under the required test conditions. Through a combination of computer simulation and physical laboratory tests of prototypes, the VBR devices obtained FDA approval.

Posted in: Briefs, Bio-Medical, Medical, Finite element analysis, Prostheses and implants, Surgical procedures, Certification

Benchtop Detection of Proteins

This process is relatively rapid and simple.

A process, and a benchtop-scale apparatus for implementing the process, have been developed to detect proteins associated with specific microbes in water. The process and apparatus may also be useful for detection of proteins in other, more complex liquids. There may be numerous potential applications, including monitoring lakes and streams for contamination, testing of blood and other bodily fluids in medical laboratories, and testing for microbial contamination of liquids in restaurants and industrial food-processing facilities. A sample can be prepared and analyzed by use of this process and apparatus within minutes, whereas an equivalent analysis performed by use of other processes and equipment can often take hours to days.

Posted in: Briefs, Bio-Medical, Medical, Water, Bacteria, Fluids and secretions, Medical equipment and supplies, Test equipment and instrumentation

Recombinant Collagenlike Proteins

These proteins can be tailored to have specific biological properties.

A group of collagenlike recombinant proteins containing high densities of biologically active sites has been invented. The method used to express these proteins is similar to a method of expressing recombinant procollagens and collagens described in U. S. Patent 5,593,859, “Synthesis of human procollagens and collagens in recombinant DNA systems.”

Posted in: Briefs, TSP, Bio-Medical, Medical, Biological sciences, Fabrication, Biomaterials

Remote Sensing of Parasitic Nematodes in Plants

A method and apparatus for remote sensing of parasitic nematodes in plants, now undergoing development, is based on measurement of visible and infrared spectral reflectances of fields where the plants are growing. Initial development efforts have been concentrated on detecting reniform nematodes (Rotylenchulus reniformis) in cotton plants, because of the economic importance of cotton crops.

Posted in: Briefs, Bio-Medical, Medical, Remote sensing, Sensors and actuators, Test procedures, Agricultural vehicles and equipment

Two Devices for Removing Sludge From Bioreactor Wastewater

These devices can operate continuously and are self-cleaning.

Two devices — a magnetic separator and a special filter denoted a self-regenerating separator (SRS) — have been developed for separating sludge from the stream of wastewater from a bioreactor. These devices were originally intended for use in microgravity, but have also been demonstrated to function in normal Earth gravity.

Posted in: Briefs, Bio-Medical, Medical, Waste materials

Portable Unit for Metabolic Analysis

Respiratory signals can be temporally resolved within respiratory cycles.

The Portable Unit for Metabolic Analysis (PUMA) is an instrument that measures several quantities indicative of human metabolic function. Specifically, this instrument makes time-resolved measurements of temperature, pressure, flow, and the partial pressures of oxygen and carbon dioxide in breath during both inhalation and exhalation.

Posted in: Briefs, Bio-Medical, Medical, Medical equipment and supplies

Advanced Resistive Exercise Device

A number of different exercises can be performed on one machine.

The advanced resistive exercise device (ARED), now at the prototype stage of development, is a versatile machine that can be used to perform different customized exercises for which, heretofore, it has been necessary to use different machines. Conceived as a means of helping astronauts and others to maintain muscle and bone strength and endurance in low-gravity environments, the ARED could also prove advantageous in terrestrial settings (e.g., health clubs and military training facilities) in which many users are exercising simultaneously and there is heavy demand for use of exercise machines.

Posted in: Briefs, Bio-Medical, Medical, Human factors, Kinematics, Product development

Rapid Engineering of Three-Dimensional, Multicellular Tissues With Polymeric Scaffolds

Engineered tissues could be grown in weeks or days instead of months.

A process has been developed for the rapid tissue engineering of multicellular- tissue-equivalent assemblies by the controlled enzymatic degradation of polymeric beads in a low-fluid- shear bioreactor. In this process, the porous polymeric beads serve as temporary scaffolds to support the assemblies of cells in a tissuelike 3D configuration during the critical initial growth phases of attachment of anchorage-dependent cells, aggregation of the cells, and formation of a 3D extracellular matrix. Once the cells are assembled into a 3D array and enmeshed in a structural supportive 3D extracellular matrix (ECM), the polymeric scaffolds can be degraded in the low-fluid-shear environment of the NASA-designed bioreactor. The natural 3D tissuelike assembly, devoid of any artificial support structure, is maintained in the low-shear bioreactor environment by the newly formed natural cellular/ECM. The elimination of the artificial scaffold allows normal tissue structure and function.

Posted in: Briefs, Bio-Medical, Medical, Biological sciences, Medical equipment and supplies, Materials properties, Polymers

Ultraviolet-Resistant Bacterial Spores

A document summarizes a study in which it was found that spores of the SAFR-032 strain of Bacillus pumilus can survive doses of ultraviolet (UV) radiation, γ radiation, and hydrogen peroxide in proportions much greater than those of other bacteria. The study was part of a continuing effort to understand the survivability of bacteria under harsh conditions and develop means of sterilizing spacecraft to prevent biocontamination of Mars that could interfere with the search for life there.

Posted in: Briefs, Bio-Medical, Medical, Bacteria, Technical review, Durability, Spacecraft

Effects of Bone Morphogenic Proteins on Engineered Cartilage

A report describes experiments on the effects of bone morphogenic proteins (BMPs) on engineered cartilage grown in vitro. In the experiments, bovine calf articular chondrocytes were seeded onto biodegradable polyglycolic acid scaffolds and cultured in, variously, a control medium or a medium supplemented with BMP-2, BMP-12, or BMP-13 in various concentrations. Under all conditions investigated, cell-polymer constructs cultivated for 4 weeks macroscopically and histologically resembled native cartilage. At a concentration of 100 ng/mL, BMP-2, BMP-12, or BMP-13 caused (1) total masses of the constructs to exceed those of the controls by 121, 80, or 62 percent, respectively; (2) weight percentages of glycosaminoglycans in the constructs to increase by 27, 18, or 15, respectively; and (3) total collagen contents of the constructs to decrease to 63, 89, or 83 percent of the control values, respectively. BMP-2, but not BMP-12 or BMP-13, promoted chondrocyte hypertrophy.

Posted in: Briefs, Bio-Medical, Medical, Anatomy, Biological sciences, Forming, Biomaterials

The U.S. Government does not endorse any commercial product, process, or activity identified on this web site.