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Biomedical subjects

L Harisiadis

Publications and source records attributed to L Harisiadis.

30 records · Page 2Linked to original sources
PubMed1978

Midline pineal tumors and suprasellar germinomas: highly curable by irradiation.

Sixty-one patients with midline pineal tumors and 16 patients with suprasellar germinomas were treated with surgical decompression and relatively high-dose radiotherapy of the primary site. Results were excellent, and there were no long-term complications. Ten per cent of midline pineal tumors and 37% of suprasellar germinomas metastasized to the cerebral or spinal subarachnoid space within 6 months to 5 years. Irradiation of the entire neural axis is recommended for locally extensive tumors, simultaneous pineal and hypothalamic lesions, and all biopsy-proved germinomas. The five-year survival rate was 79% for midline pineal tumors and 77% for suprasellar germinomas.

Adolescent↗
PubMed1978

Hyperthermia and low dose-rate irradiation.

Hyperthermia combined with 60Co gamma irradiation was studied using V79 hamster cells cultured in vitro. Modest hyperthermia (41 degrees C for 6 hrs.) enhanced the cell killing produced by acute exposure to radiation. The same treatment enhanced the effect of low dose-rate irradiation (200 rads/hr.) even more. The sequence in which modest hyperthermia was combined with low dose-rate irradiation was important. Maximal enhancement was observed when hyperthermia was followed by irradiations. The probable explanation is that, by damaging the repair system, prior heat renders the cells unable to repair sublethal damage during subsequent low dose-rate irradiation.

Animals↗
PubMed1977

Lymphopenia caused by cranial irradiation in children receiving craniospinal radiotherapy.

The peripheral blood changes were studied in 67 children who received craniospinal irradiation for posterior fossa tumors. At the completion of a cranial dose of about 3500 rad to the whole brain port, the lymphocytes were reduced to 858/mm3 rom 3084/mm3 preoperatively. The counts of the remaining leukocytes stayed at a level somewhat higher than preoperatively; the eosinophils rose to 288/mm3 from 125/mm3. With the initiation of the spinal field irradiation, which included a large proportion of the total bone marrow, the numbers of all the leukocytes decreased rapidly; the observed leukopenia was mainly secondary to neutropenia. A mechanism that was operating to restore the number of leukocytes became manifest immediately after the completion of radiotherapy, though the number of lymphocytes had not been totally restored to the preoperative level 6 years later. Irradiation of the lymphocytes that circulate through the vascular bed can explain the lymphopenia observed during cranial radiotherapy. Mild leukopenia observed in patients receiving radiotherapy through a relatively small port may be secondary to lymphopenia, and this does not necessarily indicate impaired bone marrow reserves.

Adolescent↗
PubMed1977

Thermal tolerance and repair of thermal damage by cultured cells.

Exposure of hamster cells to 42.5 degrees C for long periods leads to the development of thermal tolerance; the slope of the survival curve become shallower after about 3.5 to 4 hours. If two 4-hour exposures at 42.5 degrees C are separated by various periods of time, thermal tolerance is eliminated by 20 hours. Prolonged exposure at 42.5 degrees C offers considerable protection from subsequent treatments to acute hyperthermia at 45 degrees C indicate or in conditioned medium or balanced salt solution failed to reveal any evidence of repair of potentially lethal damage.

Animals↗
PubMed1976

The HLA system in the families of patients with juvenile diabetes mellitus.

The HLA and Bf genotypes were determined in 10 families with one or more children with JDM. A statistically significant association was found between HLA-D-identity and the chance to present JDM within a sibship. No such association was detectable with the SD antigens. A highly significant increase in the frequency of intra-HLA recombination was also found in these families.

Diabetes Mellitus, Type 1↗
PubMed1976

Subclavian artery occlusion following radiotherapy for carcinoma of the breast.

Four cases of subclavian artery occlusion occurring 5-17 years after irradiation for breast carcinoma are presented. Although arterial insufficiency is a rarely reported sequel to radiotherapy, it may be the cause of pain and disability in the upper extremity in a postmastectomy patient. Particular attention should be paid to the presence of a bruit over the subclavian and axillary arteries. Arteriography will often reveal a short, segmental lesion of the subclavian artery that frequently can be repaired surgically.

Aged↗
PubMed1975

Hyperthermia: biological studies at the cellular level.

Tissue culture techniques were used to study the effect of hyperthermia on several cell types, including normal liver and hepatoma cells, as well as cell lines that have been established in culture for many years. Short exposures (less than 30 min.) at 45 degrees C readily kill a large proportion of cells. The response to heat was strikingly similar in all cells tested, and no preferential killing of neoplastic cells could be demonstrated. By contrast, hypoxic cells were found to be dramatically more susceptible to killing by heat than aerated cells. This is the reverse of the situation for x irradiation. The effectiveness of x irradiation was potentiated by treating the irradiated cells for 20 min. at 43 degrees C, which did not kill a detectable number of cells.

Cell Division↗
PubMedDate not supplied

Transverse axial film tomography with a therapy simulator.

A tomographic attachment was designed and developed that attaches to our existing simulator. The film tomograms obtained with the aid of this device exhibit very low geometrical distortion and good contrast and resolution for the objects used in this investigation. In addition, our results to date show that adjacent areas with densities differing by as little as 5% can be distinguished on film.

Humans↗