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E Ostrander

Publications and source records attributed to E Ostrander.

4 recordsLinked to original sources

Noninvasive quantification of muscle oxygen in subjects with and without claudication.

The disabling pain of intermittent claudication (IC) arises from oxygen deprivation in the lower limbs during walking. Measurement of the oxygen deficiency within the limb tissue now appears possible with recently expanded understanding of the photon transport through tissue for photons in the visible and near infrared range. Noninvasive measurement consists of preferentially measuring photons that have traveled more deeply into limb tissues and that, therefore, may reach locations of ischemic tissue. Oxygen measurements appear to be possible up to a depth approaching 1.5 cm beneath the surface of the skin. The present study reports on data acquired from the limbs of 11 subjects with IC and 12 subjects without IC. The subjects with IC are patients with clinical findings of claudication based upon segmental Doppler pressure profiles and subjective reports by the patient of pain during exercise. The subjects without IC are individuals with no prior history of ischemic vascular disease. The results consist of photon reflectance measurements at red and infrared wavelengths (approximately 660 nm and 880 nm respectively) taken before, during, and after exercise. Infrared reflectance indices are plotted as well as oxygenation indices generated from combining red and infrared reflectances. A compilation of exercise data shows responses that are generally consistent with the expected physiological responses to mild exercise in subjects with and without IC. We anticipate that the findings of this study may lead to an objective noninvasive testing procedure for measuring the ischemic and exercise-induced changes in muscle oxygenation in the presence of claudication. If the testing of ischemic hypoxia continues to show consistency and accuracy in determining the disability of the subjects with IC, future studies can more effectively test modes of conservative management, such as cessation of smoking, alternative exercise regimens, weight loss, and alternative pharmacological agents.

Exercise↗

Use of (CA)n polymorphisms to determine the origin of blood cells after allogeneic canine marrow grafting.

We have used a polymerase chain reaction-based assay measuring polymorphic (CA)n repeats, a class of simple sequence repeats, to assess the success of allogeneic canine marrow transplants. Results were compared with those obtained with karyotype analysis of dividing cells in recipients that were sex mismatched with their marrow donors. Twenty recipients were conditioned for transplantation of genotypically DLA-identical littermate marrow by 450 cGy of total-body irradiation. In 2 recipients, results could not be compared, since either only cytogenetic or dinucleotide (CA)n marker data existed. Both dogs had autologous marrow recovery. In 15 of the remaining 18 recipients, complete agreement was found between the results obtained with dinucleotide (CA)n markers, cytogenetic studies, and granulocyte changes after transplantation. Seven of the 15 showed eventual autologous recovery, 6 displayed mixtures of host and donor cells, and 2 showed donor-type hematopoiesis. Two of the 18 dogs showed mixed chimerism with (CA)n markers and autologous recovery by cytogenetics, findings that may be related to differences in cells analyzed by the two techniques--i.e., all nucleated cells by (CA)n markers versus dividing cells by cytogenetics. In one additional recipient, results of marrow cytogenetics, granulocyte changes, and (CA)n markers were consistent with a successful allograft, while peripheral blood cytogenetics suggested autologous recovery, possibly the result of erroneous blood sampling. Polymerase chain reaction-based testing for dinucleotide repeat (CA)n polymorphisms, originally developed for genetic mapping in the dog, is useful and reliable when compared with cytogenetic studies, in assessing the success of allogeneic marrow transplants in dogs.

Animals↗