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At least 559 records · Page 31Linked to original sources
PubMed1993

A mobile real-time bioengineering front end system.

In the study of physiological system dynamics, a mobile Front End System is needed in faithfully monitoring and recording physiological signals at various experimental sites. Local real-time mode operation is required at the site of the experiment such that the significant dynamic response or event from the subject can be easily captured and displayed as the experiment progresses. An additional requirement is the interfacing with the campus computer network such that numerous network computing resources can be employed in further processing of the captured data. The system is configured by using general-purpose components such as a 50MHz PC-486, a DAS-HRES data acquisition board and some other necessary peripheral devices. An algorithm has been developed for the continuous manipulation of two queues to maintain the real-time task scheduling. Traces can be played back in forward or reverse mode at varied speed after the recording has been made. As desired, any trace segment can be picked up in the play back mode from the huge data files. The system is incorporated in a live subject bioinstrumentation laboratory and has the capability of monitoring signals from four simultaneously experimental setups. The signal types involved are membrane potentials, ECG, EMG, blood pressure, and respiratory flows and gas concentrations.

Algorithms↗
PubMed1993

Diagnosis of persistent aphthovirus infection and its differentiation from vaccination response in cattle by use of enzyme-linked immunoelectrotransfer blot analysis with bioengineered nonstructural viral antigens.

A highly sensitive enzyme-linked immunoelectrotransfer blot (EITB) assay, capable of detecting aphthovirus-specific antibodies to replicating virus in sera from cattle with persistent infection, was developed. The assay uses a set of purified recombinant DNA-derived nonstructural viral antigens as serologic probes in lieu of the traditionally used virus infection-associated antigen(s) partially purified from baby hamster kidney-infected cells. Sera from cattle with experimentally induced aphthovirus infection were analyzed sequentially by EITB at various postinoculation days, and the results were compared with those obtained by currently used techniques. It was established that, in all cases, EITB results remained positive at late stages of infection. At these times, results of virus infection-associated antigen-antibody determinations were negative by use of the conventional immunodiffusion in agarose gel test, and virus was recovered only occasionally from esophageal-pharyngeal fluid. Specificity of the EITB test was indicated by negative results for sera from cattle in aphthovirus-free areas, including samples from cattle infected with a variety of bovine viruses. Moreover, the test eliminated a substantial number of false-positive results (on the basis of the immunodiffusion in agarose gel assay) caused by reactivity of sera from vaccinated cattle. Use of additional nonstructural viral antigens, other than RNA polymerase, is proposed to differentiate between seropositivity resulting from vaccination or infection. This procedure may be considered to have potential applications as a sensitive, safe, rapid, and economic field test for specific diagnosis of persistent aphthovirus infection in affected animals.

Animals↗
PubMed1997

Ethical consciousness in bioengineering.

The role of ordinary language in expressing personal views and attitudes is a familiar one. Ordinary language can express attitudes, social demands or expectations, and moral judgments. In all these cases ordinary language has what I call practical import. Even the use of ordinary language to provide characterizations of people and interpretations of social situations can express attitudes and can imply moral judgments. Practical import is to be contrasted with theoretical import, which is mainly focused on facts and beliefs about facts. In some ways a scientific and professional education threatens to eliminate the connections between language and personal attitudes and between language and moral judgments, especially insofar as science aspires to be "detached" and morally neutral. Scientific ways of thinking and speaking tend to overlook the practical import of language and to concentrate on theoretical import alone. Professional codes of ethics and principles of ethical conduct can be helpful in counteracting this. But the general statements of codes, if they are not to degenerate into empty tautologies and pious truisms, must be understood in terms of particular cases. Finally, a brief look at some recent contributions of linguistics shows again the importance of attention to particulars. Ethical consciousness, having begun to arise even before professional education, is fostered among professionals through the use of professional codes of ethics, especially when these are understood in terms of paradigms and specific cases rather than merely general principles. The code requires professionals to use their powers of ethical judgment, not to surrender them.

Biomedical Engineering↗
PubMed1998

In situ measurements of creatine kinase flux by NMR. The lessons from bioengineered mice.

P-31 nuclear magnetic resonance (NMR) is uniquely suited to measure the kinetics of the phosphoryl-exchange reaction catalyzed by creatine kinase in intact mammalian tissue, especially striated muscle. Recently developed transgenic mouse models of the creatine kinase iso-enzyme system open novel opportunities to assess the functional importance of the individual iso-enzymes and their relative contribution to the total in situ flux through the CK reaction. This chapter reviews the most recent findings from NMR flux measurements on such genetic models of CK function. Findings in intact mouse skeletal and cardiac muscle in vivo are compared to data from purified mitochondrial and cytosolic creatine kinase in vitro. The relevance of findings in transgenic animals for the function of CK in wild-type tissue is described and the perspectives of transgenic techniques in future quantitative studies on the creatine kinase iso-enzyme system are indicated.

Animals↗
PubMedDate not supplied

[Electromagnetic bioengineering].

The results of experimental and theoretical studies on the combined action of weak electrical as well as constant and variable low-frequently magnetic fields on physicochemical and biological systems are generalised. It is shown that weak magnetic fields with parameters close to characteristics of the geomagnetic field exert selective effects, initiating the processes of chemical reactivity and ion conductivity in aqueous solutions of organic molecules.

Amino Acids↗
PubMed1976

Tibiotalar torsion: bioengineering paradigm.

1. Medial tibiotalar torsion is the most common disorder peculiar to mankind. 2. The pathogonomic findings are (a) an axial medially rotated and adducted distal third of the shaft of the tibia, (b) the plafond of the tibia with its mortise containing the "track-bound" talus, which is deflected strongly toward the tibial side, (c) an exaggerated midtarsal equinus, (d) ostensible restriction of dorsiflexion of the hindfoot against the tibia, (e) mild separation of the distal tibiofibular articulation, and (f) forward displacement of the gravitational axis to the naviculocunei-form joint. 3. Faulty leg crossing in utero resulting in an abnormal pelvofemoral-tibial design is discussed and its important consequences in the vulnerable 40 per cent of the population are emphasized. 4. The kinesiomechanics of the leg, ankle and foot is reviewed. 5. The radiographic parameters of medial tibiotalar torsion are presented, as well as the multiple facets of the clinical examination. 6. Methods of treatment depending on age and severity of the disorder are recommended. Surgery, detortional casts, and corrective footwear are discussed. Shoes presently available are inadequate for tibiotalar torsion and therefore engineering principles must be applied in the design and construction of all footwear, including sneakers and sportswear. This can be done only if the pathological biomechanics of this group of disorders is recognized. Biplane proximal tibial osteotomy is recommended in refractory cases, especially when tibiotalar torsion is demonstrated. 7. After 30 years of experience, the author finds that results with these patients have been uniformly good to excellent, depending on age and mode of treatment. 8. In medial tibiotalar torsion, the consequent adaptive changes are readily observed, but rarely are they recognized as the inevitable sequelae of medial tibiotalar torsion. 9. Adaptive compensating disorders are identified and their mechanism described. 10. The management of torsional and static disorders and adaptations of the leg, foot, and knee should not continue on an empirical basis. Recognition of recently presented parameters of the lower limbs in the vulnerable "40 percenters" permits the use of sound engineering principles in both conservative and operative correction of these disorders.

Adolescent↗
PubMedDate not supplied

Ethics education at the engineering/medicine interface.

There is a functioning interface between engineering and medicine. There are also wide-spread indications in the scientific community that there is increased concern for ethical matters in science and that the time has arrived for more instruction in this area. One reason for this in bioengineering is the rapidly growing complexity of technology in both engineering and medical biology. The ensuing difficulty in communication cannot be remedied just with more technical information. Instead bioengineers need an improved understanding of medical education and practice, and medical ethics is fundamental to this. Ethical considerations are crucial to decision making and therefore to all areas of professional endeavor in bioengineering. As a framework for ethics education, bioengineers need to gain a better understanding both of medical education in general and of medical practice, particularly the case study method in education and the nature of decision making in medical practice. Key subject areas in medical ethics for bioengineers include rights and duties of physicians, determination of death, team ethics, patient privacy and informed consent, research ethics, and malpractice. An ethics curriculum for bioengineers should be taught using both informal but regular exposure to clinical activities and clinicians, and formal classroom work. In the medical ethics classroom setting, writing assignments are essential to provoke each student to the introspection and commitment needed to form a personal professional ethos.

Biomedical Engineering↗
PubMed2005

Challenge-based instruction in biomedical engineering: a scalable method to increase the efficiency and effectiveness of teaching and learning in biomedical engineering.

Vanderbilt University, Northwestern University, the University of Texas and the Harvard/MIT Health Sciences Technology Program have collaborated since 1999 to develop means to improve bioengineering education. This effort, funded by the National Science Foundation as the VaNTH Engineering Research Center in Bioengineering Educational Technologies, has sought a synthesis of learning science, learning technology, assessment and the domains of bioengineering in order to improve learning by bioengineering students. Research has shown that bioengineering educational materials may be designed to emphasize challenges that engage the student and, when coupled with a learning cycle and appropriate technologies, can lead to improvements in instruction.

Biomedical Engineering↗
PubMed2002

Product development strategies for foods in the era of molecular biotechnology.

Breakthroughs in science and technology are accelerating development of new products that are impacting our regulatory systems. Genetically modified or bioengineering plant varieties have entered the food supply on a global basis, especially in the U.S. The U.S. Food and Drug Administration regulates on the premise of 'substantial equivalence' and has developed premarket notification procedures and voluntary labeling guidelines. Japan's Ministry of Health, Labor and Welfare regulates biotechnology products and has imposed biotechnology labeling regulations. However, the EU continues to be in a regulatory gridlock between member states and has proposed strict traceability and labeling guidelines. These requirements are currently restricting imports of bioengineered foods and are creating an international debate. In contrast to bioengineered plant varieties, to our knowledge, there are no strains of lactic acid bacterial starter cultures on the market that contain rDNA. The majority of strains have been improved via selection and mutagenesis. However, conjugation and electroporation have been used to transfer native lactococcal phage resistance plasmids to industrial strains. In addition, plasmids have been introduced to allow for selection of certain characteristics and then been eliminated by curing. The potential benefits of bioengineered foods are far reaching and are one of the most important opportunities of this century. However, bioengineered foods remain an emotional debate that is affecting world trade.

Biotechnology↗
PubMed2006

Microencapsulated nerve growth factor-expressing NIH3T3 cells-incorporated tissue engineering skin: a preliminary study.

INTRODUCTION: In order to find a suitable carrier to deliver the product of gene transfection to improve the performance of bioengineered dermis, we used microencapsulation and gene transfection technology together for the first time and found that it was feasible. METHODS: We used a recombinant nerve growth factor (pcDNA3.1+/NGF) to modify NIH3T3 cells genetically. Control of NIH3T3-NGF cells were encapsulated within microspheres composed of alginate-poly-L-lysine-alginate and cultivated in-vitro. The concentration of NGF released from the microencapsulated NIH3T3-NGF cells was confirmed using ELISA assay. We co-cultivated microencapsulated NIH3T3-NGF cells, NIH3T3 cells (control) with human keratinocytes and fibroblasts, and tested the percentage of cycle of these cells. The alkaline hydrolysis method was used to analyse the content of hydroxyproline (Hyp). Immunohistochemistry method was used to calculate the transformation efficiency from fibroblasts to myofibroblasts. RESULTS: The concentration of NGF released from the microencapsulated NIH3T3-NGF cells lasted about six weeks in the supernatant of bioengineered dermis in-vitro. The proliferation of keratinocytes, as well as the concentration of Hyp in supernatant of fibroblasts, were promoted about three times. Transformation efficiency from fibroblasts to myofibroblasts was increased approximately two-fold because of the bio-effects of NGF. Two kinds of microencapsulations were seeded into collagen which contained human fibroblasts to form bioengineered skin. Microencapsulated NIH3T3-NGF cells formed a thicker dermis. The concentration of Hyp in the bioengineered skin which indicated the level of collagen synthesis was increased due to existing NGF. CONCLUSION: Microencapsulated NIH3T3-NGF cells can be used to enhance performance of bioengineered dermis and it also can be deduced that other cytokines can be used to treat local wound areas.

Alginates↗
PubMed1988

Biological effects of non-ionizing radiations: cellular properties and interactions.

The Lauriston Taylor lectures honor the founder of the National Committee on Radiation Protection and Measurement, soon to be followed by the corresponding international organization. These standard setting bodies had a vast influence on proper recognition of radiation hazards. The 10th Taylor lecture is the first to deal with nonionizing radiations and may be, therefore, of particular interest to the bioengineer. During early history biophysics and bioengineering were primarily concerned with ionizing radiation bioeffects and electrophysiology. The nonionizing part of the radiation field and electrophysiology are closely related. Biomedical observation, biophysical and bioengineering efforts in the nonionizing radiation field are defined and complement each other. Topics concentrate on the relevant biophysical and bioengineering efforts of the author and his colleagues. They include: electrical properties of biological systems; established electrical field interactions (excitation, macromolecular responses and cellular responses); problems of dosimetry (macroscopic and microscopic considerations); conclusions about relative merits of various research approaches.

Animals↗