Melvin L. Griem

Radiosensitivity of vascular tissue. II. Differential radiosensitivity of aortic cells in vitro

The cellular outgrowths from three layers of rabbit and monkey aorta were used as primary cultures. Irradiation of the tissue fragments at the time of explanation resulted in a reduction in outgrowth of 50% with a dose of 200 rad, and in a reduction of over 90% with doses of 300 rad and above. When comparable cultures were irradiated after 2 months in vitro as a mature actively metabolizing but slowly proliferating cell population, radioresistance was increased. Subcultures of medial smooth muscle cells irradiated during their logarithmic growth phase showed a linear dose response in the cell number parameter up to 150 rad. A dose of 250 rad resulted in complete flattening of the growth curve, with a reduction in labeling index, after a 3-hr terminal [3H]TdR pulse. On the other hand, the labeling index indicated some recovery 3 days after irradiation in cultures receiving less than 250 rad. Under the same experimental conditions, cells derived from the intima of the same aorta showed no recovery when increase in cell numbers over time, or the number of labeled cells per area, were used as parameters. Cells derived from adventitia showed a relative increase in the number of labeled cells per area 4 and 7 days after irradiation following an initial decrease on Day 1.

Energetics and Mechanisms in Radiation Biology

Ed. by Glyn O. Phillips. Cloth,

Radiotherapy of hemophilia pseudotumors.

22.50. Pp. 528, with figures. New York, Academic Press, 1968. In Wales in 1967, thirty-six biologists, chemists, and physicists engaged in radiation research gathered to discuss the basic mechanisms of radiation biology. Each of the participants discussed not only his own work but also reviewed a wide range of scientific literature related to his topic. This book presents the proceedings and is extremely well illustrated with graphs, diagrams, and pictures. The data are well tabulated; formulas and mathematical treatment have been clearly presented. Each chapter is profusely documented by references. There is a convenient author and subject index. An interesting section discussing the chemical and physical processes of radiation effects in simple molecules is followed by an account of irradiated frozen aqueous systems. The information on the solvated electron, both in ice and in the aqueous state, has been reviewed. Principles, technics, and design of experiments in pulse ...

EFFECTS OF HYDROXYUREA AND RADIATION ON HAIR MATRIX CELLS

The different radiologic features of hemophiliac joint and bone changes are well known and described in the literature (1, 5). The most common manifestation of hemophilia is crippling joint deformity. The classic and typical joint and bone changes are usually seen only in authentic hemophilia or hemophilia A and in Christmas disease or hemophilia B. In cases of hemophilia C there are only minimal and slight changes in the bones and joints. In extensive hemophiliac arthropathies, the pediatrician and the orthopedic surgeon usually deal with the therapeutic problems. A hemophiliac patient has been followed for eleven years at the University of Chicago Hospitals. The first episode of bleeding was at the age of thirteen months, and at that time the diagnosis of hemophilia A was made. The patients family moved to Illinois in 1955 when he was nine years old, and he has been followed by us ever since. In the past twelve years he has had 32 admissions to our hospital with different complications of hemophilia su...

RADIATION INJURY AND RECOVERY IN ANAGEN AND TELOGEN RODENT HAIRS.

Investigations were undertaken in CF1 mice to study the effects of hydroxyurea (HU) on hair matrix cell kinetics, and to assess the effects of combined administration of HU and irradiation on induction of temporary alopecia. HU 100 mg/kg was administered intraperitoneally and each animal received tritiated thymidine 0·5 μCi/g 30 min before biopsy. Serial biopsies were taken up to 48 hr after drug administration. Autoradiographs of anagen follicle squashes revealed sharp reductions in mitotic and labeling indices within 30 min. Depressed mitotic indices of 0·6–0·9% at 1–4 hr returned to normal (2·3%) after 6 hr, followed by cyclic mitotic ‘overshoot’, and were preceded by parallel changes in the labeling indices. HU‐induced cellular damage was most marked 4 hr after HU injection, with almost complete recovery from injury observed at the 24 hr interval.

THE EFFECTS OF 250-kv X RAYS ON THE DOG'S PANCREAS: MORPHOLOGICAL AND FUNCTIONAL CHANGES

Reduced incorporation of isotope-labeled compounds was studied to assess postirradiation damage and recovery in growing (anagen) and resting (telogen) rodent hairs. Reduced uptake of

THE USE OF A SOFT DENTURE-BASE MATERIAL IN THE MANAGEMENT OF THE POST- RADIATION DENTURE PROBLEM

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MODIFICATION OF RADIATION RESPONSES OF TISSUE BY COLCHICINE

The pancreas of nine dogs was surgically isolated to the right side of the abdomen and irradiated with a total dose of 4500-5000 rads fractionated over 30 days. At the end of irradiation, and at one month, two months, and five months after irradiation, the histological changes demonstrated a progressive interstitial fibrosis and scarring which distorted the regalar architecture. The acini were reduced in number and often distorted by the fibrosis but were morphologically intact. The islets showed no histological change. Beta and alpha cells were present. One dog with a modified total pancreatic fistula survived two weeks after receiving a tissue dose of 4500 rads to the pancreas fractioned over 24 days. The total 24-hour secretory volume, and the secretory volumes following secretin and Mecholyl stimulation were unchanged during and following irradiation. The serum and pancreatic secretion electrolytes, fasting blood sugar and glucose tolerance curve were within normal limits. However, the elevated serum amylase decreased, while the concentration of amylase of the pancreatic secretion increased. The function studies confirm the morphological findings that the pancreas is radio-resistant. (auth)

Plasma-cell myeloma. A thirty-year follow-up.

One of the problems in treating malignant tumors about the oral cavity has been that of maintaining adequate dentition or a substitute following high doses of radiation to that area. With therapeutic doses of radiation to the salivary glands there is an induced dryness of the mouth, which is associated with or precipitates caries of any teeth remaining in the oral cavity (1). Because of this and the difficulty of removing teeth after radiation, it has been a policy in our institution to remove the teeth before radiation therapy to the oral cavity. Occasionally, following treatment we have seen sores develop when the denture has been improperly fitted or fitted too soon after completion of therapy. In these situations and in other denture-sore problems related to diabetes and other diseases, it has been observed that by introducing a soft denture liner between the methyl methacrylate dental base and the epithelium covering the alveolar ridges, the sore could be treated (2, 3). Since this observation, we ha...

Cysteamine protection of x-ray-induced dysplasia in mouse hair.

Several recent reviews have described the effects of various chemical and physical agents in modifying radiation responses in normal tissues and tumors (1–3) . The observation that irradiation induces profound morphologic changes in animal and human hairs (4, 5) has provided a useful experimental device for the screening of such agents in rodents (6). At any given time areas of skin in rats and mice can be found in which most of the hair follicles are in the resting phase of the hair cycle. These telogen hair follicles are mitotically inactive and are insensitive to radiation (4). If the resting hair is disturbed by plucking, its follicle becomes active and a growing (anagen) hair is formed which is highly radiosensitive. When anagen hairs are irradiated, dysplastic changes in the shafts and atrophy of the bulbs occur, the number of hairs affected being proportionate to the dose of radiation sustained. Recent experiments in rats and mice have shown that anagen hairs also undergo profound atrophic and dysp...