Radioactive Phosphorus Research Articles

Essential Thrombocythemia in Young Adults

Essential thrombocythemia is typically a disorder of adults in the sixth or seventh decade of life and is characterized by frequent thrombohemorrhagic complications. In young patients, the optimal management of complications is controversial. We studied 56 young adults (33 female and 23 male patients) with a diagnosis of essential thrombocythemia. The mean duration of follow-up was 4.68 years. The mean platelet count at diagnosis was 1,328,000/mm3. Platelet aggregation studies in 21 patients demonstrated hypoaggregation to epinephrine; spontaneous platelet aggregation was present in 4. At diagnosis, 39 patients were asymptomatic, and thrombocytosis was discovered incidentally. Throughout follow-up (up to 20 years), 24 patients remained asymptomatic. Thrombotic complications developed in 24 patients; they were life-threatening in only 3. The most common vaso-occlusive symptoms were migraine headache (in 12 patients) and erythromelalgia (in 3). Minor hemorrhagic complications occurred in six patients, and none was life-threatening. Serious complications (one cerebral and two myocardial infarctions) occurred in three patients, all of whom recovered. Two deaths occurred, neither of which was attributable to essential thrombocythemia. The treatment regimens used were chemotherapy in 9 patients, antiaggregating agents in 7, radioactive phosphorus in 1, the newer platelet-lowering agent anagrelide in 10, and only observation in 29. No treatment-related acute leukemias developed. This series of young patients with essential thrombocythemia, the largest to date, demonstrates a low incidence of life-threatening complications and a favorable long-term prognosis. Therapeutic recommendations should remain conservative, and potential leukemogens should be avoided unless serious complications develop. Anagrelide may be useful in young patients with thrombocythemia who are symptomatic.

Autoradiographic Detection of Lesser Cornstalk Borer (Lepidoptera: Pyralidae) Eggs in Soil Environments

A nondestructive method of detecting lesser cornstalk borer, Elasmopalpus lignosellus (Zeller), eggs in soil is outlined. Fourth instar larvae were fed a diet containing radioactive phosphorus (4 μ Ci/g), and eggs laid by females that emerged from these larvae contained sufficient radioactivity to expose X-ray film. Fecundity, oviposition rates, and longevity were similar for 32P-labeled adult females and unlabeled adult females. In greenhouse tests using corn planted in simulations of conventional tillage and no-tillage conditions, eggs were autoradiographically detected in soil and on plant tissue.

Comparison of Xenon Arc and Argon Laser Photocoagulation in the Treatment of Choroidal Melanomas

We analyzed the follow-up data in 38 consecutive patients with selected choroidal melanomas that were treated by photocoagulation between 1971 and 1980. Indications for treatment included photographic documentation of tumor growth or an unequivocally positive radioactive phosphorus uptake test, or both. Xenon arc photocoagulation was used in 22 patients (58%) and argon laser was used in 16 patients (42%). At the time of data analysis, the length of follow-up was at least 58 months in all patients. Although all treated tumors were initially eradicated according to ophthalmoscopic and fluorescein angiographic criteria, there was subsequent regrowth in three of the 22 patients (14%) treated with xenon photocoagulation and in ten of the 16 patients (64%) treated with argon laser. The recurrences were observed on an average of 71 months after completion of treatment in the xenon-treated group and on an average of 30 months in the argon-treated group. More treatment sessions were required in the argon laser group to achieve tumor control. Complications of vitreous hemorrhage, cystoid macular edema, and retinal detachment were greater in the xenon photocoagulation group.

Stereotactic Internal Irradiation for Cystic Craniopharyngiomas: A 6-Year Experience

Fourteen adults and 4 children with cystic craniopharyngiomas were treated with stereotactic beta-irradiation during a 6-year period. Of these patients, 10 were primary cases, and 8 were recurrences after previous major surgery. Radioactive phosphorus (32P) or yttrium (90Y) in colloidal forms were used as the radiation agents. Cyst volumes (10-130 ml) were assessed intraoperatively by the 99Tc radiodilution method. According to our treatment program, the radiation dose to the cyst wall was 20,000 rad and the total irradiation time 2 weeks. The follow-up period ranged from 1 to 6 years, with an average of 3.8 years. Postoperative shrinkage of the cysts and clinical improvement were observed in most patients. Pertinent clinical data and results of treatment are described.

Polycythemia vera. A clinical study of 141 patients.

The clinical course of 141 unselected patients (64 m, 77 f, median age 59) with polycythemia vera (PV), treated during the period 1967 to 1986 was analyzed to study prognostic factors and the correlation between treatment strategies and complication rates. Therapy was performed according to a prospectively defined treatment protocol. Primary control of the disease was achieved by phlebotomy. Marrow suppression by radioactive phosphorus or low dose busulphan was used only as a second-line therapy or to lower high platelet counts. The clinical course of the patients was characterized by a low rate of acute leukemia (4%) and a high rate of thromboembolic complications (40%). Myelofibrosis developed in 17 patients (12%). Median survival of the patents was 9.4 years. The prognostic influence of several parameters at the time of diagnosis was tested: age, sex, spleen size, percentage of blood blasts + promyelocytes, leucocyte count, platelet count, hemoglobin, hematocrit, reticulocyte count and the values of the lactate-dehydrogenase (LDH) and the alkaline neutrophil phosphatase (ANP) all had no significant influence on the length of survival. The prognosis of PV patients with atypical disease presentation at diagnosis was not different from patients with typical disease.

Grain boundary diffusion of phosphorus in polycrystalline silicon

Diffusion of radioactive phosphorus in polycrystalline silicon has been studied in the temperature range 566-980 degrees C. Diffusion profiles were obtained by anodic oxidation sectioning coupled with radio tracer detection. Diffusion coefficients in the grain boundary were obtained following Leclaire's method of analysis. An Arrhenius plot of grain boundary diffusion coefficients gave rise to an activation energy of 2.65 eV and pre-exponential factor D'0=4.8*10-3 cm2 s-1.

The treatment of essential thrombocythaemia with radioactive phosphorus

The major complications of essential thrombocythaemia include haemorrhage and thrombosis, events which are related to the level of the abnormal platelet count. We report here on the use of radioactive phosphorus (32P) in eight patients with essential thrombocythaemia. Two patients required multiple injections of 32P to control platelet count, and there was no reduction in the rate of fall of platelets with each injection. Three patients required chemotherapy for persistent thrombocythaemia despite multiple doses of 32P. No clinical or haematological characteristics could be identified for those patients whose disease was difficult to control. Radioactive phosphorus is a safe and effective method to control platelet counts in patients with essential thrombocythaemia.

DNA-Restriction Enzyme Analysis of Adenoviruses Isolated from Waters

Adenoviruses can often be isolated from waters in Greece. Among them, serotype adenovirus 7 (Ad 7) was found most frequently, accounting for nearly 55% of all adenovirus isolates from water, with the protamine sulphate precipitation method used. The corresponding isolation rate of the Ad 7 serotype from humans was even higher, approaching 85% of all human isolates. This high frequency of occurrence of the Ad 7 serotype prompted us to perform a DNA restriction enzyme analysis of Ad 7 strains, so as to find their genome type. Twenty eight strains, 14 from waters and 14 from humans, were grown in Hep2 cells in the presence of radioactive phosphorus. Viruses were harvested after 24 hours incubation, the DNA was extracted and digested with the endonucleases of Bam HI and XhoI. DNA restriction digests were electrophoresed in agarose gels, vacuum dried and autoradiographed. The comparison of the restriction digests showed that all strains from waters and 12 out of 14 from humans belong to the genome type Adeno 7b, which is the most prevalent in other European countries as well.

Predation and Food as Factors Affecting Survival of Nezara viridula (L.) (Hemiptera: Pentatomidae) in a Soybean Ecosystem

Direct field observations and use of radioactive phosphorus (32P) as a tracer showed 18 insect and 6 spider species, representing 6 orders and 19 families, to be predators of Nezara viridula (L.) in a soybean ecosystem in Louisiana. Solenopsis invicta Buren was the dominant egg predator during the vegetative stages of soybean development, while cannibalism of eggs by adults and nymphs of N. viridula was also frequently observed during this stage. Grasshoppers were the more important egg feeders during the reproductive stages of plant development. Life tables developed for N. viridula in field cages showed that survival to adult was 0.5% during the vegetative and flowering stages and 4.5% during pod set, but it increased significantly to 38.2% when seeds were formed. Under field conditions during the latter period, survival to fourth-instar nymphs declined to 8.7%, from which it was concluded that, in this particular ecosystem, 33.6% mortality was caused by predation and 57.7% was due to other factors.

Polycythaemia vera in young people: an analysis of 58 cases diagnosed before 40 years

SummaryOver 20 years, 58 cases of PV in young people (46 meeting the full PVSG criteria, 12 with elevated red cell volume and leucocytosis or thrombocytosis, without splenomegaly) were studied and have been followed for periods of 3–24 years. These cases represent approximately 5% of the cases of PV referred to the Department of Nuclear Medicine of St Louis Hospital during this period. They differ from older patients in the initial clinical severity, the short interval between the first symptoms and the diagnosis, frequent presentation with a life‐threatening complication (two cases of hepatic vein thrombosis, six thrombotic or haemorrhagic events, six splenectomies, two abortions) and a very enlarged spleen in half the cases. However, after the initial complications, the overall survival is very long (exceeding 70%, even when including the initial complications, at 15 years).The vascular accidents occur exclusively in the phlebotomized patients, the main risk factor being the poor stability of the haematocrit. Only one acute leukaemia was observed among the 14 cases treated by radioactive phosphorus and/ or alkylating chemotherapy. The most frequent late complication was evolution towards myelofibrosis. This spent phase seemed to occur earlier in patients treated by phlebotomy.On the basis of this data, we would advise the following therapeutic strategy: phlebotomies, as soon as the diagnosis is established, and a systematic long‐term treatment by hydroxyurea with the hope of reducing the number of vascular complications and of delaying the evolution towards the spent phase and the myelofibrosis.

Polycythaemia vera in young people: an analysis of 58 cases diagnosed before 40 years.

Over 20 years, 58 cases of PV in young people (46 meeting the full PVSG criteria, 12 with elevated red cell volume and leucocytosis or thrombocytosis, without splenomegaly) were studied and have been followed for periods of 3-24 years. These cases represent approximately 5% of the cases of PV referred to the Department of Nuclear Medicine of St Louis Hospital during this period. They differ from older patients in the initial clinical severity, the short interval between the first symptoms and the diagnosis, frequent presentation with a life-threatening complication (two cases of hepatic vein thrombosis, six thrombotic or haemorrhagic events, six splenectomies, two abortions) and a very enlarged spleen in half the cases. However, after the initial complications, the overall survival is very long (exceeding 70%, even when including the initial complications, at 15 years). The vascular accidents occur exclusively in the phlebotomized patients, the main risk factor being the poor stability of the haematocrit. Only one acute leukaemia was observed among the 14 cases treated by radioactive phosphorus and/or alkylating chemotherapy. The most frequent late complication was evolution towards myelofibrosis. This spent phase seemed to occur earlier in patients treated by phlebotomy. On the basis of this data, we would advise the following therapeutic strategy: phlebotomies, as soon as the diagnosis is established, and a systematic long-term treatment by hydroxyurea with the hope of reducing the number of vascular complications and of delaying the evolution towards the spent phase and the myelofibrosis.

Growth of Thiobacillus ferrooxidans on Elemental Sulfur

Growth kinetics of Thiobacillus ferrooxidans in batch cultures, containing prills of elementary sulfur as the sole energy source, were studied by measuring the incorporation of radioactive phosphorus in free and adsorbed bacteria. The data obtained indicate an initial exponential growth of the attached bacteria until saturation of the susceptible surface was reached, followed by a linear release of free bacteria due to successive replication of a constant number of adsorbed bacteria. These adsorbed bacteria could continue replication provided the colonized prills were transferred to fresh medium each time the stationary phase was reached. The bacteria released from the prills were unable to multiply, and in the medium employed they lost viability with a half-life of 3.5 days. The spreading of the progeny on the surface was followed by staining the bacteria on the prills with crystal violet; this spreading was not uniform but seemed to proceed through distortions present in the surface. The specific growth rate of T. ferrooxidans ATCC 19859 was about 0.5 day, both before and after saturation of the sulfur surface. The growth of adsorbed and free bacteria in medium containing both ferrous iron and elementary sulfur indicated that T. ferrooxidans can simultaneously utilize both energy sources.

A chromosomal profile of polycythemia vera.

One hundred four patients with a diagnosis of polycythemia vera and a variable period of follow-up had one or more cytogenetic investigations. Chromosome abnormalities were found in 13% of untreated patients, in 56% of cases treated with radioactive phosphorus (32P) or cytotoxic drugs, and in 85% of patients in which transformation of the disease had occurred. Nonrandom chromosome abnormalities found before treatment included +8, +9, 13q-, 20q-; their prognostic value is little, as they are often associated with longstanding, stable disease. In contrast, 5q- anomaly and the appearance of subclones in patients with an abnormal karyotype were found to be poor prognostic signs, as they are usually coincidental with evolution of the disease to myelofibrosis or leukemia. Chromosomally two patterns of acute leukemia were observed in polycythemia vera patients. The first type resembles de novo acute leukemia, in that the clinical and cytologic characteristics of the disorder are easily defined by FAB criteria and the chromosome changes compatible with the types usually found in those conditions. In the second type, assignment to a FAB morphologic subgroup was more difficult, myelodysplastic changes were often present, and the karyotype showed complex abnormalities frequently involving chromosomes #5 and #7. All these features suggest the occurrence of secondary leukemia.

Hydroxyurea in the treatment of polycythemia vera: a prospective study of 100 patients over a 20-year period.

From 1963 to 1983, I treated 100 patients with polycythemia vera, using phlebotomy and the adjunctive agent hydroxyurea. These 78 male and 22 female patients ranged in age from 24 to 88 years (mean 55.7). Duration of therapy ranged from three to 216 months (mean 64.9). The mean daily dose was 0.72 gm, and the median dose was 0.64 gm. Hydroxyurea gave adequate control of red cells, platelets, and spleen size. Cytopenia was not observed. Phlebotomy requirements were markedly reduced. Leukocyte alkaline phosphatase scores were generally lowered and several blood chemistry values returned to normal. Side effects were minimal, and there were no drug-related deaths. Infections were not a problem. Hydroxyurea, a metabolic inhibitor of desoxyribonucleic acid, does not interfere with the synthesis of ribonucleic acid or protein and is thus probably less leukemogenic than radioactive phosphorus and alkylating agents. Acute myelogenous leukemia was seen in one patient after five years of continuous hydroxyurea therapy. He had received no other myelosuppressant agent. Because hydroxyurea is safe and effective in the treatment of polycythemia vera, it should be considered as first-line therapy. It probably offers practical and theoretic advantages over present therapy particularly when the disease is not well controlled by phlebotomy alone.

Profile characteristics, and form and surface activity of inorganic phosphorus in a deep red Kenya coffee soil (Nitosol)

SUMMARYThe paper examines some of the physical and chemical properties of a deep red friable clay profile (Nitosol) developed in the Kenya highlands over trachyte. This soil is widely planted to coffee. The profile is remarkable for the depth and uniformity of the B horizon and for its stable microaggregation. Despite a clay content of 50–60% throughout the deep solum, the soil feels and handles like a loam.Work with radioactive phosphorus on samples from the profile and from nearby experimental plots under coffee showed that the activity, and the amounts, of surface phosphate fractions decreased in the order Fe‐P, Al‐P and Ca‐P, but the order of decrease of specific surface activity was Al‐P, Fe‐P, Ca‐P. The relative availabilities of these forms is discussed.

Comparison of computerized tomographic and radionuclide methods in determining intracranial cystic tumor volumes

The dosimetry of radioactive phosphorus (32P) for intracavitary treatment of cystic brain tumors is dependent upon accurate determination of the cyst volume. The authors have used both high-resolution computerized tomography (CT) scanning and an isotope dilution technique with technetium-99m (99mTc) sulfur colloid to determine cyst volumes in an experimental model and in six patients with intracerebral cystic tumors. In six separate comparisons using an experimental phantom "cyst," no significant differences between CT and 99mTc values were detected. In six patients with cystic neoplasms varying from 3 to 6.7 ml in volume, the percent differences between values obtained by CT and isotope dilution ranged from -17.26% to +13.13%. In individual patients, these differences proved to be of little significance for planning dosimetry. In both experimental and clinical trials comparing isotope dilution and CT measurement techniques, the CT technique using the standard software of the scanner and 5-mm thick slices proved to be a highly accurate method of determining cyst volume. The authors now base dosimetric calculations for intracavitary radiation with 32P on CT technique alone.

Influence of root structure on uptake and transport of radioactive phosphorus

A simple device to observe the role of individual root zones in the uptake and transport of nutrients is described. The results confirmed the specific significance of the different anatomical structure of primary seminal maize root in ensuring the uptake and transport of phosphates. In32p-uptake, the highest portion />40%/was taken up by zone in distance of 0–5 mm from root cap. On the other hand, the lowest transport was shown in the zone 25–30 mm from root tip. The portion of this zone was 40% from the total received supply.

Cataract Surgery and Intraocular Lenses in Patients with Unsuspected Malignant Melanoma of the Ciliary Body and Choroid

During a recent four-year period, 21 patients were referred to the Oncology Service at Wills Eye Hospital with previously unsuspected posterior uveal melanomas in an eye that had been operated upon for a unilateral cataract. Twelve of the 21 patients had undergone standard cataract extraction and nine had had implantation of an intraocular lens, which was often in juxtaposition to the unsuspected melanoma. Preoperative ultrasonography in these patients had apparently been performed only to obtain an axial length of the globe and the eye was not scanned for pathologic processes in the posterior segment. Management of the melanoma included a cobalt plaque in eleven cases, enucleation in five, periodic observation in three, iridocyclochorioretinectomy in one, and orbital exenteration in one. It is stressed that a thorough external and slit-lamp examination, transillumination, carefully performed ultrasonography and, if necessary, a radioactive phosphorus uptake test can establish the diagnosis of uveal melanoma and prevent diagnostic delay and misdirected therapy in such cases.

The Jackass Penguin (Spheniscus demersus) as a pelagic predator

The Jackass Penguin (Spheniscus demersus) as a pelagic predator

Treatment of polycythemia vera with hydroxyurea.

Conventional treatment of polycythemia vera (PV) with radioactive phosphorus or alkylating agents is associated with a significant excess of acute leukemia and cancer of the gastrointestinal tract and skin. There is thus a need for a nonmutagenic agent in the treatment of this disorder. Hydroxyurea (HU) was administered to 118 patients with a loading dose of 30 mg/kg/day for 1 week, which was then reduced to 15 mg/kg/day. Initial control of the elevated hematocrit and platelet count was achieved within 12 weeks in over 80% of patients. Long-term disease control was defined and the accumulative 1-year failure-free survival was 73% in the previously untreated patients and 59% in those patients previously treated with other myelosuppressive modalities. The HU was well tolerated and cytopenia, which generally occurred within the first 8 weeks of therapy, was transient and of little clinical significance. However, it is recommended because of this toxicity that HU be administered initially at a dose of 15-20 mg/kg/day. Three patients developed acute leukemia; two were untreated and one had had myelosuppressive therapy. Hydroxyurea is an effective agent in the treatment of PV, but continued assessment of its mutagenic potential is necessary.