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Biomedical subjects

K H Woodruff

Publications and source records attributed to K H Woodruff.

31 records · Page 2Linked to original sources
PubMed1979

Comparison of heavy particle with X-irradiation on the hamster lung.

Important new modalities for cancer therapy are being developed, and one of the most promising is heavy charged particle irradiation. We are currently assessing the effects of 375-MeV/nucleon neon irradiation in the plateau region of ionization compared to 230KVp X-rays on the whole thorax of hamsters. Single dose levels for neon irradiation ranged from 150-1000 rad. Dose levels for X-irradiation ranged from 225-1500 rad. The animals were followed for 1 year after irradiation, and the most useful results emerged, using morphometric methods. One year after irradiation, pulmonary parenchyma and nonparenchyma appear morphometrically unchanged. However, the volume density of pulmonary septums, septal cells, all tissue, connective tissue, and alveolar Type II cells was increased while the volume densities of alveoli, empty alveolar space, and capillary lumens were diminished. Most of these changes were dose dependent not clearly demonstrable until a year after irradiation. The relative biologic effect of neon compared to X-irradiation using this techniques is 1.6-1.8.

Animals↗
PubMed1976

Morphologic and morphometric analysis of the early effects of x-ray and heavy-ion irradiation of hamster lung.

Morphometric methods were to used to compare the early effects of graded single doses of x-rays with accelerated heavy particle (helium or neon) irradiation of hamster lung. Increased values in the volume densities of both capillary lumina and inflammatory cells at 2 weeks postirradiation were observed. Neon-ion irradiation wes statisically different from x-irradiation at all dose levels, while helium-ion irradiation showed significant increases only at higher doses (1000 to 1500 rads). At 1 month post-irradiation, the volume densities of capillary lumina after heavy particle irradiation began to return to control values, while those in x=irradiated lungs continued to be elevated. The volume density of inflammatory cells remained increased for all types of irradiation, and the highest values were obtained in neon-ion irradiated lungs. Accelerated heavy particle irradiation would therefore appear to elicit a more intense early radiation than does x-irradiation but the chronic significance of these findings is not yet known.

Animals↗
PubMed1976

Scanning electron microscopy of Mycoplasma-infected tracheal rings.

Sequential changes visualized by scanning electron microscopy are described in hamster tracheal ring cultures exposed to 10(5) colony-forming units/ml of Clyde strain M-129 Mycoplasma pneumoniae. Loss of cilia, elevation of cell borders, and clumping of microvilli were induced within six hours after incubation of the rings in media containing mycoplasmas and in sterile used media. This finding lends support to the theory that the toxicity of Mycoplasma infection is partially attributable to alterations in the growth medium or elaboration of a toxic substance by the organisms. Mycoplasmas were observed attaching to tracheal ring surfaces eight hours after infection. With increasing periods of incubation, cell death and alterations occurred in tracheal surface structure that might be confused with the organisms.

Animals↗
PubMed1975

Tolerance of the spinal cord of rats to irradiation with cyclotron-accelerated heliumions.

Spinal cords of rats were exposed to either single doses of helium ions ranging from 500 to 3500 rads, or to fractionated doses of helium ions ranging from 1300 to 6530 rads using 10 equal fractions given over 22 days. Both plateau and spread-out Bragg peak regions of ionization were used. For single doses there was no difference betweenplateau or spread-out Bragg peak ionization regions for production of paralysis; thetolerance dose for production of paralysis was about 1900 rads. For the fractionation experiment, there was also no difference between plateau or spread-out Bragg peak ionization regions for production of paralysis; the tolerance dose was between 5220 and 6530rads. Comparison of dose levels producing about 10% partial paralysis indicates that about 500 rads of dose is recovered between fractions. In both single dose and fractionated experiments, latency between onset of paralysis was between 20 to 24 weeks.

Animals↗
PubMed1973

Cystinosis.

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Cystinosis↗
PubMed1973

Ultrastructural changes in hamster tracheal ring cultures exposed to Mycoplasma pneumoniae.

Ultrastructural studies of lung biopsies in this laboratory from 2 children with chronic respiratory disease and elevated titers to Mycoplasma pneumoniae showed increased pleomorphic lysosomes in alveolar macrophages. This suggested that intracellular digestion might be an important feature of mycoplasma infection and an in vitro study was undertaken. Tracheal ring cultures from 35 Syrian hamsters were exposed to Clyde M129 strain of M pneumoniae. Controls consisted of untreated tracheal rings from the same animals. Both groups were subjected to light, fluorescent, and electron microscopy. Cultures exposed to virulent mycoplasma exhibited specific immunofluorescence at mucosal surfaces and in the submucosa. Mucosal cytopathic changes and submucosal necrosis were prominent. Submucosal macrophages contained increased numbers of lysosomes, some of which contained mycoplasma-like forms. If Mycoplasma pneumoniae are ingested by macrophages, this would provide a mechanism through which immune phenomena could occur and would partially explain the prominent peribronchial lymphocytic accumulation of human mycoplasma infection.

Animals↗
PubMedDate not supplied

Heavy-ion radiography: density resolution and specimen radiography.

Heavy-ion radiography is performed by the passage of a beam of nuclei accelerated to energies of several hundred MeV/nucleon through an object. The technique of recording transmitted nuclei in a downstream stack of plastic sheets affords excellent resolution of density by recording the nuclei only at their stopping points. Imaging of a phantom--which stimulated tumors of low density contrast in a body part--by conventional radiography, computed tomographic scanning and the heavy-ion technique indicated superior density resolution for heavy-ion imaging at radiation dose. Superior imaging of tumors in pathologic specimens was demonstrated for heavy-ion imaging compared to conventional radiography. Values of stopping power for various tumors and normal tissues were determined by a computer-aided technique. Heavy-ion radiography shows promise for superior imaging of low contrast tumors at relatively low radiation low levels.

Achilles Tendon↗