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PubMed1992

Detection of Listeria monocytogenes by non-radioactive RNA probe and polymerase chain reaction.

A HindIII fragment, 651-base-pair, from the listeriolysin 0 gene of Listeria monocytogenes was cloned into pGEM4Z. Radioactive 32P labeled and non-radioactive digoxigenin labeled RNA probes were made by in vitro transcriptions. These probes hybridized only to L. monocytogenes strains. Polymerase chain reaction was performed by using a 22-mer and a 23-mer oligonucleotide primer, and segment of about 700-base-pair was amplified only in L. monocytogenes strains and this band was visualized by hybridization with the non-radioactive probe.

Base Sequence↗
PubMed2004

Radioactive microspheres in therapeutics.

Microspheres as a drug delivery system hold great promise in reaching the goal of controlled drug delivery as well as site specific delivery. In the last few decades, scientific and technological advancements have been made in the research and development of radiolabeled microspheres. These are used successfully for the treatment of various cancers and tumors. Since response to chemotherapy and external radiotherapy is not so effective and hazardous too, so an alternative to this is internal radiation therapy. These radiolabeled microspheres are very stable and have a proven efficacy in the field of primary as well as metastatic cancers. Radioactive microspheres can be selectively targeted to various tumors without undue radiation to the nontumorous tissues. The radioactive microspheres are injected to halt tumor growth via the blood supply, thereby enabling surgical removal once the tumor size decreases. This review provides an outlook to various aspects of radioactive microspheres and their role in treatment of various tumors and cancers.

Albumins↗
PubMed2004

Radioactive coil embolization of intracranial aneurysms: minimal inventory to reach target activities in a virtual series of 154 patients.

BACKGROUND AND PURPOSE: Recanalization after selective endovascular treatment of intracranial aneurysms with platinum coils has been widely reported in the literature. Beta radiation emitted from (32)P ion-implanted coils can prevent recanalization in animal models. A complete inventory of radioactive coils may not be realistic; our hypothesis was that it might not be necessary to reach target activities in most aneurysms. A limited supply of three or four types of coils may decrease the inventory difficulties related to the use of an isotope with a half-life of 2 weeks. METHODS: We reviewed 154 aneurysms selectively treated with standard coils. We calculated the volumetric activity obtained if all coils (simulation 1) were radioactive with linear activities of 0.13 (scenario I) or 0.26 microCi/cm (scenario II). Then, we simulated a treatment with standard coils plus a selection of radioactive coils limited to three (simulation 2) or four types of commonly used coils (simulation 3). Resulting activities were calculated and reported to the lesion volume. For each scenario and simulation, the percentage of lesions, in which the target volumetric activity (0.018 microCi/mm3) was reached, was reported. RESULTS: Success in reaching target volumetric activities varied from 55-99% according to different simulations. A supply of four types of coils was sufficient to reach target activities in 86-95% of patients commonly treated in our institution. Target activities were difficult to reach in giant aneurysms. CONCLUSION: It is feasible to reach target activities in most lesions by using a limited coil supply.

Computer Simulation↗
PubMed2004

Treating amiodarone-induced thyrotoxicosis with radioactive iodine.

Amiodarone use in the United States is increasing including a role in advanced cardiac life support protocols. There has been a significant increase in hypothyroidism, destructive thyroiditis (type II), and iodine-induced thyrotoxicosis (type I) with amiodarone. Preexisting thyroid disease and status of iodine intake can determine the nature of iodine-induced thyroid disease. Treating amiodarone-induced thyrotoxicosis (AIT) may include traditional antithyroid agents, glucocorticoids, and surgery. Usually, it is assumed the radioactive iodine uptake (RAIU) will be low, and this choice as a treatment modality is excluded at the initial visit. We report a satisfactory outcome in a patient with AIT using radioactive iodine. The role of radioactive iodine in treating AIT is reviewed

Aged↗
PubMed2004

[Expression and significance of caspase-3 gene in apoptotic muscle cells 103Pd radioactive stent bile duct in dogs].

OBJECTIVE: To discuss the expression and significance of caspase-3 gene in the apoptotic muscle cells in gamma-radiation-induced muscle cell lines. METHODS: The caspase-3 mRNA in the control and gamma-radiation induced apoptotic muscle cells was analysed by RT-PCR. RESULTS: The expression of caspase-3 gene transcript was higher in 103Pd radioactive stent dog bile duct than in general stent dog bile duct, and apoptotic muscle cells were higher in 103Pd radioactive stent dog bile duct than in general stent dog bile duct. CONCLUSIONS: The high level expression of caspase-3 gene may help to understand the muscle cells sensitivity to gamma-radiation apoptosis. 103Pd radioactive stent may increase the expression of caspase-3 gene in dog bile duct and prevent the billiary narrow when dog bile duct was injured by balloon.

Animals↗
PubMed2004

Marked survival prolongation of mice bearing a transplantable colon adenocarcinoma by treatment with radioactive platinum-[125I]histamine complex. Preliminary report.

BACKGROUND: Recently, a new PtCl2-histamine complex, and its radioactive analogues labelled with I-131 and I-125 have been synthesised and investigated both in vitro and in vivo. In this preliminary report the survival rate of radioactive platinum-[125I] histamine therapy in tumour-bearing mice is demonstrated. MATERIAL AND METHODS: A murine model of transplantable colon adenocarcinoma (C38) in C57BL/6 mice (15 days postimplantation) was used for the experiment. Three groups of animals were treated every 2-3 days with five intraperitoneal injections of the following preparations: PtCl2Hist (total dose of Pt--125 micromol/kg), PtCl2[125I]Hist (total dose of I-125--4.2 MBq; Pt--13 micromol/kg), and "Active/Cold"--PtCl2[125I]Hist/PtCl2Hist (I-125--4.2 MBq; Pt--125 micromol/kg). A solution of 15% dimethylformamide in saline was applied to the control group. A survival analysis with the Kaplan-Meier estimation of survival curves and a statistical comparison by a log-rank test was applied to evaluate the anticancer activity of the tested preparations. RESULTS: Treatment of the animals with platinum-histamine preparations resulted in a significant prolongation of survivals, especially if the radioactive complex with carrier-added PtCl2Hist (p < 0.005) was applied. The highest, almost a 60% prolongation of survival was observed in the Active/Cold group (MStr/MScon ratio = 1.58, 95% CI 1.22-1.93). For this group there was the lowest risk of death (hazard ratio HR = 0.29), whereas HR = 0.45 and 0.47 were found in the animals treated with unattended PtCl2Hist and 125I-labelled complex, respectively. CONCLUSION: The significant enhancement of in vivo anti-cancer activity by a concomitant combination of the therapeutic factors, i.e. cytotoxic/cytostatic activity of the platinum(II)-histamine and the Auger electrons effects generated by the attached I-125 radionuclide, was found on the murine model of transplantable colon adenocarcinoma.

Adenocarcinoma↗
PubMed2006

[CT guided radioactive seed 125I implantation in treatment of pancreatic cancer].

OBJECTIVE: To investigate the clinical value of CT guided radioactive seed (125)I implantation in treatment of pancreatic cancer. METHODS: Twenty-six patients with pancreatic cancer 6.1 cm in size on average, 21 males and 5 females, aged 60 +/- 13 (47 - 73), underwent CT guided radioactive seed (125)I implantation. Of the 26 patients 15 had the symptom of severer abdominal pain and 10 had jaundice. Three of them were in the TNM (pTNM) stage II, 30 in the stage III, and 3 in the stage IV. Treatment plan system was used to design the distribution of the seed (125)I needed. Under CT guidance, the (125)I seeds of (2.2 - 3.3) Mq were implanted into the pancreatic cancer at a distance of 1.0 - 1.5 cm. A follow-up for 3 - 12 months was conducted. RESULTS: Complete relief (CR) of the symptoms was seen in 9 patients, partial relief (PR) in 2 patients, and no change (NC) in 4 cases with an effective rate of 73.4%. The abdominal pain was relieved 3 - 7 days after the implantation. CT performed 2 months after implantation showed CR in 2 cases, PR in 13 cases, NC in 5 cases, and progression in 5 cases with an overall effective rate of 57.7%. Four patients died of local progression and 2 patients died of distant metastasis. Migration of the seeds into the liver was seen in 3 patients and slight decrease of white blood cells was seen in 1 patient during the 2-month follow-up. No severe complications, such as pancreatic leakage, acute pancreatitis, intestinal hemorrhage, etc, were found. CONCLUSION: Safe and with minimal damage and few complications, CT guided radioactive seed (125)I implantation is effective in treatment of pancreatic cancer.

Aged↗
PubMed2006

Log normal distribution of cellular uptake of radioactivity: implications for biologic responses to radiopharmaceuticals.

UNLABELLED: It is widely recognized that radiopharmaceuticals are generally distributed nonuniformly in tissues. Such nonuniformities are observed over the entire range of spatial levels, ranging from organ to subcellular levels. The implications of nonuniform distributions of radioactivity for dosimetry, and ultimately for the biologic response of tissues containing radioactivity, have been investigated extensively. However, there is a paucity of experimental data on the distribution of cellular activity within a population of cells. In the present study, the distribution of activity per cell is experimentally determined and its implications for predicting biologic response are examined. METHODS: Chinese hamster V79 cells were exposed to different concentrations of (210)Po-citrate. The radiolabeled cells were washed, seeded into culture dishes or glass slides, covered with photographic emulsion, and stored in an opaque container. Subsequently, the emulsion was developed, thereby resulting in observable alpha-particle tracks that were scored. RESULTS: The distribution of activity per cell was found to be well described by a log normal distribution function. Theoretic modeling of cell survival as a function of mean activity per cell showed that survival curves differed substantially when the activity per cell was log normally distributed versus when it was assumed conventionally that every cell in the population contained the mean activity. CONCLUSION: The present study provides experimental evidence of log normal cellular uptake of radioactivity. Theoretic calculations show that a log normal distribution of cellular activity can have a substantial impact on modeling the biologic response of cell populations.

Animals↗
PubMed2006

The radioactive drug research committee: Background and retrospective study of reported research data (1975-2004).

In the United States, human research involving radioactive drugs must be conducted under a Food and Drug Administration (FDA) investigational new drug (IND) application, unless specifically exempt from IND requirements, or under the direct oversight of a Radioactive Drug Research Committee (RDRC) as long as certain conditions are met. Research overseen by RDRCs is considered basic science research when its purpose is to advance scientific knowledge and not to determine a radioactive drug's safety and effectiveness as a therapeutic, diagnostic, or preventive medical product in humans. We retrospectively reviewed and analyzed available study data from annual reports submitted to the FDA dating back to 1976. In 1976, there were 18 studies involving 531 subjects compared with 2003, when there were 284 RDRC studies involving 2,797 subjects. In 1976, RDRC subjects were imaged 5% of the time using positron-emitting nuclides and 77% of the time with conventional gamma-emitting nuclides. In 2003, this was reversed with 77% using positron emitters and 5% using conventional gamma-emitters. In 1976, pediatric studies comprised 7.3% of all RDRC subjects; today pediatric RDRC studies are rarely conducted. Today the RDRC is used primarily by large medical research institutions. Although the program has a very good safety record, RDRC's 30-y-old regulations need to be revised to be consistent with current scientific knowledge and health policy.

Biomedical Research↗
PubMed2006

[Radioactive seed implantation in treatment of oral and maxillofacial malignancy].

OBJECTIVE: To treat oral and maxillofacial malignant tumors with radioactive seed implantation and observe the therapeutic results and side effects. METHODS: Thirty-six patients with oral and maxillofacial malignancy were treated by radioactive seeds implanting (operation and seed implantation or seed implantation only). The treatment plans were designed before implanting by treatment plan system (TPS). All patients were followed up for 6 - 36 months with an average of 14 months and the results evaluated. RESULTS: In 3 patients treated only by seed implantation, the tumor size reduced obviously and the symptoms alleviated in 2 patients with advanced disease, and the tumor got complete remission in one patient with tongue cancer. In the other 33 patients who were implanted after operation, no recurrence was seen in the target area, but recurrence or lymph node metastasis was found outside the target area in 3 patients. There were no unusual complaint and external radiotherapeutic side effects except for skin hyperemia occurred in 8 patients. CONCLUSIONS: Radioactive seed implantation is very effective for preventing recurrence and metastasis of oral and maxillofacial malignancy.

Adolescent↗
PubMed1992

Experimental study on radioactive pathways of hypodermically injected technetium-99m.

The objective of this study was to investigate the biological substrate of radioactive pathways of migration of hypodermically injected 99mTc into points of low electrical resistance. Sixteen anesthetized adult male beagles were used. Control and test points were defined by comparing their electrical resistance to that of the pinna. Seventy-three experiments of three different types were performed: (1) separate hypodermic injections of [99mTc] sodium pertechnetate, 201Tl-chloride, 131INa and 99mTc-rhenium sulfide into control and test points; (2) simultaneous injections of [99mTc]sodium pertechnetate and 201Tl chloride into control and test points; and (3) intravascular injections of 99mTcO4 into blood vessels underlying test points. Only the hypodermic injection of 99mTc into points of low electrical resistance gave rise to a specific radioactive pathway characterized by rapid and longitudinal migration, clearly independent of background activity. The specific radioactive pathway detected is not the result of diffusion of the radiotracer through nerves, veins or lymphatic vessels, but its trajectory coincides with that described for one of the acupuncture meridians in the dog.

Animals↗
PubMed1991

Non-radioactive detection of the rearranged BCR/ABL sequences amplified by polymerase chain reaction.

The polymerase chain reaction (PCR) is a powerful technique for the detection of the bcr/abl rearrangement in chronic myelogenous leukemia (CML). It allows the exponential amplification of the rearranged region, thus facilitating its detection. The specificity of the bcr/abl cDNA sequence amplified by PCR is most commonly verified by hybridization to a 32P-labeled probe. In this paper, an assay for the colorimetric detection of the amplified bcr/abl fragment is described, which offers several advantages over the use of radioactive probes. We adapted the PCR for synthesis and simultaneous labeling of DNA fragments with a non-radioactive steroid compound called digoxigenin. This labeling procedure was used to generate a digoxigenin-labeled internal probe for the chimeric bcr/abl mRNA. The assay described is based on the hybridization of the amplified bcr/abl sequence to the non-radioactively labeled probe and on the subsequent detection by an enzyme-linked immunoassay and enzyme-catalyzed color reaction. Using this protocol, we investigated 20 patients with CML along with six healthy individuals and two cell lines derived from patients with CML for the presence of the bcr/abl rearrangement. It is shown that the assay is both highly sensitive and specific and that it is readily applicable to the routine diagnosis of CML. In addition, the assay could be adapted to a number of clinical diagnostic uses.

Colorimetry↗
PubMed1990

[Therapeutic consequences of contamination injuries by highly radioactive substances].

A case of plutonium injury of the left hand is used to explain the correct management. In addition to radical surgical excision under repeated monitoring of radioactivity, it is obligatory to commence parenteral chelation therapy with DTPA. Close cooperation with radiological technologists is necessary. Discharges and used bandages have to be analysed for their radioactive content before elimination as radioactive waste. Isolation of the patient is not required. The relevant government department has to be contacted. A health center for radiation victims with special measuring equipment is desirable.

Accidents, Occupational↗
PubMed1988

[Treatment of hyperthyroidism by radioactive iodine in France].

A change in ideas concerning the use of radioactive iodine in the treatment of hyperthyroidism has revived interest in this therapy. We report the results of an enquiry conducted in all French nuclear medicine units regarding their activity in 1985 and compare these results with those of a similar enquiry conducted simultaneously in Belgium. The amount of radioactive iodine administered in France was one-half of that administered in Belgium. Regional differences were quite marked in France, probably due to different schools of thought. Diffuse hyperthyroidism accounted for two-thirds of the indications. Most patients received one single dose. The primary objective was a return to euthyroidism, but one third of the units accepted the risk of hypothyroidism. Synthetic antithyroid drugs were often used as adjuvants. In one-half of the units, the radioactive dose administered to each patient was calculated from the effective period of the radioelement and from the thyroid mass. In 1 out of 3 units the patients were hospitalized in a controlled area for a mean period of 3 days. French doctors generally respected the 40-year age limit and systematically excluded children and teenagers. Long-term follow-up was carried out in only 50 per cent of the units.

Antithyroid Agents↗
PubMedDate not supplied

[Pulmonary scintigraphy using the inhalation of monodispersed radioactive aerosols. Preliminary report].

This article describes a method for inhalatory lung scintigraphy (ILS) by the use of radioactive monodisperse aerosols, with particles smaller than 2 microns. We discuss the findings in normal subjects, in patients with pulmonary embolism (PE) or/and obstructive pulmonary disease (OPD), and in individuals with severe pulmonary hypertension. This procedure has several advantages over the use of radioactive gases, such as 133Xe and 81Krm: lower cost, easier to perform, several scintigraphic projections in one study, acquisition of perfusion and inhalatory images in a single session, and inhalatory and perfusion images with identical spatial resolution and similar data density. It is concluded that ILS with radioactive monodisperse aerosols is a useful method for the study of OPD and in conjunction with perfusion lung scintigraphy is helpful in the diagnosis of PE.

Aerosols↗
PubMed1988

[Radioactivity in dismantling a betatron].

The authors report on the specific radioactivity of construction components of a 42 MeV betatron measured 28 days after the last run by means of a Ge spectrometer (ultra-pure germanium detector employed in a semiconductor spectroscopic method) recording the gamma spectra of various components of the betatron. This examination served to find out which components would have to be considered as radioactive waste requiring special treatment in accordance with Federal German legislation on radioactive waste disposal (section 47 of the Radiation Protection Ordinance). The examination showed that such special treatment would be required only for the target (main material: platinum) and the Platness-filter (chief constituent: lead) of the decommissioned electron accelerator.

Humans↗
PubMed1987

Extrapulmonary radioactivity in lung permeability measurements.

The pulmonary clearance rate of aerosolized and deposited [99mTc]DTPA is used to assess pulmonary epithelial permeability to solutes. To evaluate whether it is necessary to correct these measurements for radioactivity in the chest wall and pulmonary vasculature five patients with no ventilation to one hemithorax were studied. After inhaling a submicronic aerosol of [99mTc]DTPA a gamma camera measured count rates over both hemithoraces for 20 min. The observed T1/2 for clearance from the normal hemithorax was 56 min (range 18-115 min), and when this was corrected for chest wall contribution (derived from the abnormal hemithorax) the average T1/2 was 52 min (range 17-107 min). To simulate infinitely permeable lungs we measured thoracic radioactivity in two adults and six children who were injected i.v. with a known amount of [99mTc]DTPA. The count rate over the thorax was only 8.1% (range 2.7%-11%) of that obtained when a similar amount of aerosolized [99mTc]DTPA was deposited in the lungs during a subsequent study. We conclude that it is not necessary to correct for nonpulmonary epithelial radioactivity during the measurement of [99mTc]DTPA clearance rate from the lungs.

Adult↗