The purpose of this study was to examine some of the parameters of saccharin avoidance relating to varying dose sizes of the colloidal suspension, Proferrin. Since studies reveal additive effects when irradiation and Proferrin are used together, it was hypothesized that different degrees of avoidance would be obtained by using various dose levels.

The purpose of this study was twofold: 1) to present experimental data on changes in permeability of fibers during irradiation using Na22 as the tracer isotope, and 2) to attempt to correlate these findings with the electrical changes observed.

The effects of X-irradiation at dosages of 40 r, 80 r, 160 r, 240 r, 320 r, 400 r, 800 r, 4 Kr, 8 Kr, and 16 Kr on the oxygen uptake of frog brain (Rana pipiens) tissue slices were studied. A membrane-covered oxygen electrode method was used to measure the respiratory rate. Continuous recordings were made before, during, and following X-irradiation in all of the test experiments. X-irradiation was delivered from a G. E. beryllium window X-ray unit at 120 KVP, 5 ma with a 1/4 mm Al filter.

Exactly where in the hypothalamus is the adrenal-pituitary response to X-irradiation "triggered" or initiated? Moreover, does ionizing radiation act directly on specific centers in the brain or does it act indirectly via the production of some humoral agents? Finally, what role does the hypothalamus play in the radiation-syndrome? The purpose of the present study was to attempt to answer these questions by determining the effects of two stressor agents, X-irradiation and electrical stimulation applied either singly or together, on the activity of the adrenal-pituitary axis. The parameters measured were changes in plasma corticosterone, in circulating eosinopihils, and in adrenal gland weight.

The effects of a lethal dose (1380 r) of X-irradiation on plasma and adrenal tissue histamine levels of rats were studied. The plasma histamine response was triphasic (increase at 1-3 hours, decrease at 5 and 9 hours and return to control at 24 hours post-irradiation). The adrenal tissue histamine response was found to be biphasic (decrease at 1 to 9 hours and a return to control level at 24 hours post-irradiation).

The purpose of this study, therefore, was threefold in nature: (1) to determine the effects of x-irradiation on the influx and efflux of potassium in compound nerve fibers (2) to attempt to relate the radiation-induced changes in electrical activity with potassium flux and (3) to use the information obtained to gain insight into the possible cellular site (s) of radiation insult to compound nerves.

Thesis (M.A.)--Boston University / PLEASE NOTE: Boston University Libraries did not receive an Authorization To Manage form for this thesis or dissertation. It is therefore not openly accessible, though it may be available by request. If you are the author or principal advisor of this work and would like to request open access for it, please contact us at open-help@bu.edu. Thank you. / The general problem of alteration in viral susceptibility by the irradiation of monolayers of tissue cells in culture was examined in this study; specifically an increased susceptibility of HeLa (an established cell line which was derived from an epidermaid carcinoma of the cervix) to destruction by herpes simplex virus (the virus commonly associated with cold sores or fever blisters). The experimental procedures included the study of the radiosensitivity of the cell line, survival curve analyses expressed as the efficiency of plating, that is the per cent of viable cells capable of forming colonies visible to the unaided eye within twelve days, and finally infectivity studies. Tissue culture has proved to be a very useful tool in the study of radiation effects on tissues of higher animals since the effects of radiation can apparently be explained on the cellular level. Many types of cells have been studied but in all cases the most striking characteristic in irradiated populations is the increased cell size. Ionizing radiation effects both the reproductive and synthesizing capacity of cells with the former being the more sensitive. Some irradiated cells never divide while others divide several times before reproduction stops. After the cells stop dividing, they continue to grow in size forming giants because synthesis of the cellular constituents continues. Giant cells resulting from x-irradiation are more readily destroyed by the action of viruses than are non-irradiated cells. PUCK & MARCUS reported that NDV when plated on a mixture of giant and normal cells, destroyed more of the giants than normal cells. An enhancement of cell susceptibility following irradiation was also demonstrated for two enteroviruses by HSIUNG. The increased susceptibility of x-ray-induced giant cells to CPE of virus and the earlier release of virus by such cells was also demonstrated by LEVINE in studies with the Leon strain of type 3 polio. Many tissue culture-virus systems have been used to demonstrate alterations in susceptibility induced by x-irradiation, but few investigators have used a HeLa-HSV system to study this altered susceptibility using low levels of irradiation (50 roentgens to 500 roentgens) [TRUNCATED] / 2031-01-01

The purpose of the present study was sixfold: 1. To study the effects of x-irradiation on spinal cord activity. 2. To study the effects of CNS drugs on spinal cord function as reflected by changes in the ventral root potentials. 3. To ascertain whether one can alter the observed spinal response to ionizing radiation by applying CNS drugs prior to, during, and following x-irradiation of a given spinal cord segment. 4. To shed some light on the role of higher brain centers on spinal reflexes. 5. To shed some light on the loci of radiation insult to the spinal cord. 6. To establish evidence for a possible drug-irradiation interaction in mammals.

Due to the relatively small amount of work concerning radiation, it was thought feasible to use ionizing radiation as a tool to study the relationship between water and salt flux in isolated root systems. Moreover, the more quantitative potometric method lends itself well to such a study, since the two processes can be followed simultaneously. the aims of this study, therefore, were 1) to determine effects of X-irradiation on water, calcium and potassium flux in excised onion roots; 2) to determine the dose levels required for producing permeability changes; 3) to investigate the nature of radiation damage to root systems; and 4) to attempt to shed light on the relation between water transport and ion movement in root systems.

The purpose of the present study was twofold: (1) to determine if X-irradiation can be considered a direct stress agent, and if so, to what extent it differs from other stressors; and (2) to further elucidate the role of the adrenal cortex in the radiation syndrome by determining the more immediate responses of this system to X-irradiation.