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Eucalyptus globulus essential oil was evaluated for its genotoxic potential using a somatic segregation assay and a diploid strain of the fungus Aspergillus nidulans, heterozygous for nutritional and conidia color markers. The main compounds of the current essential oil sample were eucalyptol (49.0 %), alpha-pinene (8.9), beta-pinene (1.5), globulol (6.9), alpha-eudesmol (1.12), spathulenol (1.42), gamma-cadinene (1.45), trans-beta-elemenone (1.23) and aromandendrene (2.3), totaling 74 % of oil. Oil at 0.12 and 0.25 microL/mL was found to increase the mitotic instability of the original diploid strain and the number of diploid mitotic recombinants of A. nidulans. The genotoxicity of the oil was associated with the induction of mitotic crossing-over or with oil-broken chromosomes.

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The heterokaryotic and vegetative diploid phases of Colletotrichum lindemuthianum are described using nutritional and biochemical markers. Nitrate non-utilizing mutants (nit), derived from R2047, R89, R73, R65, and R23 isolates, were paired in all possible combinations to obtain heterokaryons. Although pairings R2047/R89, R2047/R73, R65/R73, and R73/R23 showed complete vegetative incompatibility, prototrophic heterokaryons were obtained from pairings R2047/R65, R2047/R23, R65/R89, R65/R23, R73/R89, R89/R23, R2047/R2047, R65/R65, R89/R89, R73/R73, and R23/R23. Heterokaryons gave rise to spontaneous mitotic segregants which carried markers corresponding to one or the other of the parental strains. Heterokaryons spontaneously produced prototrophic fast-growing sectors too, characterized as diploid segregants. Diploids would be expected to yield auxotrophic segregants following haploidization in basal medium or in the presence of benomyl. Parental haploid segregants were in fact recovered from diploid colonies growing in basal medium and basal medium containing the haploidizing agent. Although barriers to the formation of heterokaryons in some crosses were detected, the results demonstrate the occurrence of parasexuality among vegetative compatible mutants of C. lindemuthianum.

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Cisplatin (cis-diamminedichloroplatinum, cis-DDP) and cytosine arabinoside (ara-C) are anticancer drugs used in the treatment of human cancer. The two chemotherapeutic drugs were tested in current research for their recombinogenic potential in diploid cells of Aspergillus nidulans. Non-cytotoxic concentrations of ara-C (0.4 and 0.8 microM) and cis-DDP (1.5, 3.0 and 6.0 microM) were strong recombinagens in A. nidulans UT448//A757 diploid strain, which induced homozygosis of recessive genetic markers, previously present in heterozygous condition. Drugs significantly increased homozygosity index (HI) values for five nutritional genetic markers when compared with those determined in the absence of anticancer drugs. Since mitotic recombination is a mechanism leading to malignant growth through loss of heterozygosity at tumor-suppressor loci, ara-C and cis-DDP may be characterized as secondary promoters of malignant neoplasia in diagnosed cancer patients, after chemotherapy treatment.

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The heterokaryotic and vegetative diploid phases of Colletotrichum lindemuthianum are described using nutritional and biochemical markers. Nitrate non-utilizing mutants (nit), derived from R2047, R89, R73, R65, and R23 isolates, were paired in all possible combinations to obtain heterokaryons. Although pairings R2047/R89, R2047/R73, R65/R73, and R73/R23 showed complete vegetative incompatibility, prototrophic heterokaryons were obtained from pairings R2047/R65, R2047/R23, R65/R89, R65/R23, R73/R89, R89/R23, R2047/R2047, R65/R65, R89/R89, R73/R73, and R23/R23. Heterokaryons gave rise to spontaneous mitotic segregants which carried markers corresponding to one or the other of the parental strains. Heterokaryons spontaneously produced prototrophic fast-growing sectors too, characterized as diploid segregants. Diploids would be expected to yield auxotrophic segregants following haploidization in basal medium or in the presence of benomyl. Parental haploid segregants were in fact recovered from diploid colonies growing in basal medium and basal medium containing the haploidizing agent. Although barriers to the formation of heterokaryons in some crosses were detected, the results demonstrate the occurrence of parasexuality among vegetative compatible mutants of C. lindemuthianum.

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The polymerase chain reaction showed high sensitivity for detecting Trypanosoma cruzi in the blood of mice, independent of clonal genotype (19, 20-T. cruzi I; 32, 39-T. cruzi II) or phase of the infection (acute or chronic).

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PURPOSE: This study was undertaken to assess the toxicity and possible benefits from the administration of low-dose external-beam irradiation for Age-Related Macular Degeneration (ARMD). The premise of the treatment is that radiation induces regression and/or promotes inactivation of the subretinal neo-vasculature, resulting in reabsorption of fluid and blood thus reducing the risk for further leakage or bleeding, as well as subretinal fibrosis. Clinically, the beneficial effect could be translated into stabilization of visual acuity and prevention of progression of the wet type of ARMD with the possibility for some visual improvement. METHODS AND MATERIALS: Allegheny University Hospitals, Hahnemann, Department of Radiation Oncology, treated 278 patients prospectively beginning in January 1995 with low-dose irradiation for wet-type macular degeneration. Two hundred forty-nine patients were treated with a total dose of 14.40 Gy in eight fractions of 1.80 Gy over 10-13 elapsed days, and 27 patients with 20 Gy at 2 Gy per fraction over 12-15 days. The first two patients were treated to a total dose of 10.00 Gy in five fractions of 2.00 Gy. Patients were evaluated at 2-3 weeks and 2-3 months. A percentage (36.7%) of the patients had previously received laser treatments in the study eye, 21.9% once, 5% twice, 9.7% three or more. Subjective visual acuity and toxicity data was collected on all patients. RESULTS: At 2-3 weeks after treatment 195 patients (70%) retained their visual acuity without change, 68 patients (24.5%) stated they had improved vision, and 15 patients (4.8%) stated their vision continued to decrease. Two to 3 months after treatment, 183 patients (65.8%) had no change in their vision, 75 patients (27%) had an improvement in their vision, and 20 patients (7.2%) had a decrease in visual acuity. Transient acute reactions occurred in 14 of the 278 patients treated. CONCLUSION: Our observations in this group of 278 patients support the conclusion that many patients will have improved or stable vision after treatment with low-dose irradiation for age related wet type macular degeneration.

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Local control of unresectable esophageal carcinomas remains a significant problem in spite of aggressive treatments. External beam radiation therapy, chemotherapy, and combined modality treatment have all been employed with limited success. Here we review the existing literature and our own experience with external beam radiation followed by low-dose-rate or high-dose-rate intracavitary radiation for carcinoma of esophagus. The addition of intracavitary brachytherapy to external beam irradiation is well tolerated, causes no significant toxicity, and improves local control. Low-dose-rate intracavitary boost compared to high-dose-rate intracavitary boost has the advantage of a greater margin of safety, requires a single application, does not require highly sophisticated computerized technology, and is accompanied with fewer high-grade toxicities. Combined modality therapy consisting of concomitant infusional chemotherapy, external beam irradiation, and low-dose-rate intracavitary boost needs to be investigated.

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Carcinoma of the female urethra is uncommon. The review of literature and our own experience indicates that early distal urethral cancers (squamous and adenocarcinoma) can be treated either with surgery (70-80% 5-year survival) or with radiotherapy (brachytherapy) with excellent results (75% 5-year survival). Early proximal or entire urethral cancers (squamous and adenocarcinoma), if treated surgically, will require exenterative procedures. Alternatively, these cancers can be treated with a combination of external beam and brachytherapy with or without chemotherapy with good results and preservation of organs. Surgery can be used for failures or persistent tumors. Advanced cancers require a multimodality approach, and a combination of radiation and chemotherapy appears to be the optimal way to treat these patients-with surgery to be used for biopsy-proven persistent tumors or recurrences.

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PURPOSE: This study attempted to assess the toxicity and possible preliminary benefits from the administration of low-dose external beam irradiation for age-related macular degeneration (ARMD). The premise of the treatment is that radiation induces regression and/or promotes inactivation of the subretinal neovasculature which would result in reabsorption of fluid and blood. This would reduce the risk for further leakage or bleeding, as well as subretinal fibrosis. Consequently, the beneficial effect could be translated into stabilization of visual acuity and prevention of progression of the wet ARMD with the possibility for slight improvement. METHODS AND MATERIALS: Allegheny University Department of Radiation Oncology treated 41 patients prospectively from January through October 1995 with low-dose irradiation for wet-type macular degeneration. A total of 39 patients were treated with a total dose of 14.4 Gy in eight fractions of 1.8 Gy/fraction over 10-13 elapsed days. The first two patients were treated with a total dose of 10 Gy in five fractions of 2 Gy. Patients were evaluated at 2-3 weeks and 2-3 months. Some of the patients (36.7%) had laser treatments in the study eye: 21.9% (9) once, 5% (2) twice, 9.7% (4) thrice or more. Subjective visual acuity and toxicity data were collected on all patients. RESULTS: At 2-3 weeks after treatment 29 patients (70%) retained their visual acuity without change, 10 (24.5%) stated they had improved vision, and 2 (4.8%) stated their vision continued to decrease. At 2-3 months after treatment, 27 patients (65.8%) had no change in their vision, 11 (27%) had an improvement in their vision, and 3 (7.2%) had a decrease in visual acuity. Six patients of 41 in the treated group had acute transient side effects. CONCLUSION: Our observations in this group of 41 patients support the conclusion that many patients will have improved or stable vision after treatment with low-dose irradiation for age-related wet-type macular degeneration.

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With the discovery of radium by Curie in 1898, researchers recognized that this unique radionuclide had specific biologic properties that were applicable to treating patients with cancer. In the beginning, the radium sources were placed within cavities as independent sources and, when needles were available, implanted into tissues. The first combination of brachytherapy, technologies with external-beam radiation therapy was reported by Wright at the Memorial Sloan-Kettering Cancer Center in New York in 1914 in the treatment of a patient with cervical cancer. Next, there was a rapid implementation of brachytherapy in the treatment of cancer by intracavitary placement of radionuclides, interstitial implantation technologies, and systemic administrations. With the development of new radionuclides, including cesium-137, cobalt-60, iridium-192, iodine-125, palladium-103, ruthenium-109, strontium-90, iodine-131, and californium-225, which had varying types of radiation emissions appropriate when properly selected in treatment of cancer, there was a rapid development of innovative technologies to treat all malignancies, especially gynecologic cancer. The evolution of events brought forth new applicators and techniques that allowed for better distribution of the radiation dosage within the tumor being treated, safer use of radionuclides, and the development of computer programs allowing for varying source applications and dose distributions within the volume implanted.

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Esophageal stricture is an uncommon complication in HIV-negative patients treated with radiation to the chest for lung cancer. There have been a number of recent reports on the association of cancer and HIV-positive patients, as well as a greater sensitivity to radiation therapy of the mucous membranes in HIV/AIDS patients. This article reflects a review of the literature on the risk of major complications and morbidity of the esophagus in HIV+/AIDS patients whose chests are treated with radiation for lung cancer. Included is a report of a previously unpublished case of an early and severe esophageal reaction to radiation therapy in an AIDS patient.

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Fifty-nine patients with primary presentation of high-grade gliomas of the brain, 13 with astrocytomas with anaplastic foci and 46 with glioblastoma multiforme, were treated with surgical intervention and definitive postoperative radiation therapy followed by multiple intravenous administration of iodine-125-labeled monoclonal antibody-425, which binds specifically to human epidermal growth factor receptor. The total cumulative labeled antibody doses ranged from 40 to 296 mCi. The administration of the radiolabeled antibody was performed in most instances within 3 months following completion of the primary surgery and radiation therapy. No significant life-threatening toxicities were observed during the trial. At one year, 34 (58%) of the 59 patients in the trial were alive. The median overall survival for both groups was 13.5 months.

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In 1993, roughly 1,170,000 new cases of invasive cancer will be diagnosed in the United States. A considerable portion of these patients who die will do so because of uncontrolled local and/or regional disease. Numerous advances in the radiologic treatment of cancer have led to improved local and regional control, as well as survival. These advances include improved radiologic imaging techniques, improved techniques of radiation therapy, innovative brachytherapeutic techniques, intraoperative electron beam therapy techniques, and stereotaxic radiosurgical techniques. In this paper, the authors discuss these techniques with specific attention to how they have lead to improved local and regional control, as well as cancer cure with organ preservation.

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Seventy-eight patients with pituitary adenomas were seen in the Department of Radiation Oncology at Hahnemann University between 1961 and 1986. Most were treated with megavoltage photons with or without prior surgery. In this group, 68 patients were followed: 39 were treated with radiation therapy (RT) alone, and 29 were treated with a combination of surgery and RT (S/RT). Patients were followed for 2 to 20 years. Of 68 patients, (97%) experienced complete response to treatment; 86% of the RT patients remained free of disease at 5 and 10 years. In the S/RT group, 100% and 94% remained free of disease at 5 and 10 years, respectively. Total disease-free survivals at 5 and 10 years were, respectively, 91% and 89%. The majority of the failures occurring in the RT group were with growth hormone-secreting tumors and Cushing's disease. Of the 7 patients that failed or recurred (time to recurrence: 1-16 years posttreatment), 6 have been followed: 4 were treated with surgery, 1 with RT, and 1 with S/RT. All 6 have remained free of disease since salvage, with 2- to 14-year follow-up periods. Serious morbidity and mortality have been reported previously with bitemporal field radiation using kilovoltage and low megavoltage RT. However, there was no temporal lobe necrosis or death in any of the patients in this study.

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Ameloblastoma of the jaw is an aggressive benign tumor of epithelial origin that has generally been treated surgically even for metastases. This article is a review of the literature and a report of a previously unpublished case. Despite earlier reports, it is suggested that the available data clearly indicate that it is a radiosensitive tumor. In this report, specific recommendations for radiation therapy are outlined, and guidelines for treatment planning, radiation dosage, and fractionation expected outcome and follow-up are given.

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