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Sample records for 125i permanent implant

  1. Permanent 125I implants in head and neck cancer

    International Nuclear Information System (INIS)

    One hundred twenty-four patients were treated with advanced recurrent head and neck cancer for palliation with radioactive permanent Iodine-125 (125I) implants. Complete regression occurred in 71% of the 118 lesions for which evaluation was possible and greater than 50% regression occurred in 18%; no meaningful regression occurred in 11%. Local recurrence of cancer was subsequently seen in 21% of the lesions which had regressed completely, in 55% of those which had regressed incompletely, and in 100% of those which had not regressed. The incidence of serious complications was 5.5%. Overall, in 64% of the instances the implanted lesions remained controlled until the patient's death, usually due to progression of cancer elsewhere in the body. It is concluded that permanent 125I implants offer useful palliation to the patient with recurrent head and neck cancer with a minimum of toxicity and inconvenience. Because of their low toxicity even after prior full-course external radiation therapy, the authors are currently investigating their use as planned adjunct to external radiation therapy and chemotherapy in the initial definitive management of patients with locally advanced head and neck cancer

  2. Ten cases of metastatic cervical cancer with the treatment of permanent 125I seeds interstitial implants

    International Nuclear Information System (INIS)

    Objective: To investigate the clinical effect of permanent 125I seeds interstitial implants for metastatic cervical cancer. Methods: Under the guidance of the B-sonography, 125I seeds were implanted into the eleven cervical lymph nodes of ten patients who had been given tumor resection. The pain relief and tumor size were observed in regular follow-up after one-month treatment. Results: All the patients were followed up for 6-14 months,and the postoperative recovery was good with no complication. One month after the implantation, the pain symptom was alleviated entirely in two nodes and partly in nine nodes. The tumor size shrank in ten nodes while there was no change in one node after one month. Conclusion: Permanent 125I seeds interstitial implants for metastatic cervical cancer is a safe, minimally invasive and effective treatment. (authors)

  3. Interstitial permanent implantation of 125I seeds as salvage therapy for superficial metastatic tumor

    International Nuclear Information System (INIS)

    Objective: To investigate the clinical effect of 125I seeds interstitial permanent implant for superficial metastatic tumor. Methods: Under the guidance of the B-ultrasonography, 125I seeds were implanted into 28 units of the superficial metastatic tumor in 24 patients who had been given tumor resection, and the pain relief and tumor size were observed by means of B-ultrasonography and CT regularly after 1 month. Results: All the patients were followed-up for 1-14 months, and the median length of follow-up was 8 months. The symptoms recovered well with no adverse reaction after operation. One month after the implantation, the pain symptom was alleviated entirely in 23 lesions and partly in 5 lesions. The tumor size shrank in 25 lesions and there was no change in 3 lesions. Conclusion: Radioactive 125I seeds interstitial permanent implantation is a simple, safe, effective method which can improve living quality of patients and ease the pain and local compression. (authors)

  4. Verification of air-kerma strength of 125I seed for permanent prostate implants in Japan

    International Nuclear Information System (INIS)

    To assure the physical quality of brachytherapy, we investigated the difference between measured and manufacturer's stated source strengths in a single model SourceTech Medical (STM) 1251 125I seed. A well-type ionization chamber with a single-seed holder was used to measure the source strength of 2412 125I seeds before implant in 34 patients. The air-kerma strength was 0.450 U for all cases. The mean source strength for each patient was measured and compared with the manufacturer's stated value. The deviation from the measured value was compared with the tolerance range of the American Association of Physicists in Medicine (AAPM) TG-56 report's recommendation. The measured source strength was higher than the manufacturer's stated value, with a median difference of 1% (range, -2% to 5%). Sixteen of the totals of 2412 seeds (0.7%) were more than 5% different from the manufacturer's stated value. The median standard deviation (SD) from the mean value was 2.2% (range, 1.1% to 2.5%) for all patients. This is the first report of a single-seed assay performed for the model STM1251 125I seed. In this study the manufacturer's stated strength agreed well with the measured value. Nevertheless, the advisability of performing a single-seed assay at every institution should be considered, by referring to the appropriate regulations; for example, those used in the United States. (author)

  5. CT-guided percutaneous permanent 125I implantation for patients with malignant tumor

    International Nuclear Information System (INIS)

    Objective: To evaluate the feasibility, safety, and efficacy of CT-guided permanent iodine-125 implantation for malignant tumors. Methods: Thirteen lesions in 10 consecutive patients with malignant tumor were treated with CT-guided iodine-125 permanent implantation brachytherapy, of which four cases were primary unresectable carcinoma and six cases were metastases. There were 4 males and 6 females, the mean age was 56.9 years (range 54 to 62 years). Based on the CT imaging within two weeks before the implantation of the seeds, a computer-based treatment planning system was used to determine the optimal seed distribution. Subsequent CT-guided needle placement and seed implantation were carried out. Post-implant CT scans were performed immediately and five to ten months after the implantation in all cases to assess seed distribution, complication, and curative effect. Results: CT-guided iodine-125 permanent implantation was accomplished smoothly in all cases. This technique offered a better seed placement. The number of seeds implanted in one lesion was 1 to 44 (mean 18.6). No acute complications and late toxicity related to the implantation were observed. Pain relief was obtained in all four patients (100%) presenting with pain. Follow-up CT demonstrated that 3 of 13 lesions disappeared completely, eight lesions diminished, and the remaining 2 lesions had no significant change in size. Mean lesion size of pre-implant and post-implant were 3.15 cm and 2.06 cm, respectively (t=5.127, P<0.001). Conclusion: CT-guided iodine-125 permanent implantation is a feasible, effective, and safe method in the treatment of both primary unresectable carcinoma and metastases. (authors)

  6. Prostatic edema in 125I permanent prostate implants: Dynamical dosimetry taking volume changes into account

    International Nuclear Information System (INIS)

    The purpose of this study is to determine the impact of edema on the dose delivered to the target volume. An evaluation of the edema characteristics was first made, and then a dynamical dosimetry algorithm was developed and used to compare its results to a standard clinical (static) dosimetry. Source positions and prostate contours extracted from 66 clinical cases on images taken at different points in time (planning, implant day, post-implant evaluation) were used, via the mean interseed distance, to characterize edema [initial increase (Δr0), half-life (τ)]. An algorithm was developed to take into account the edema by summing a time series of dose-volume histograms (DVHs) with a weight based on the fraction of the dose delivered during the time interval considered. The algorithm was then used to evaluate the impact of edema on the dosimetry of permanent implants by comparing its results to those of a standard clinical dosimetry. The volumetric study yielded results as follows: the initial prostate volume increase was found to be 1.58 (ranging from 1.15 to 2.48) and the edema half-life, approximately 30 days (range: 3 to 170 days). The dosimetric differences in D90 observed between the dynamic dosimetry and the clinical one for a single case were up to 15 Gy and depended on the edema half-life and the initial volume increase. The average edema half-life, 30 days, is about 3 times longer than the previously reported 9 days. Dosimetric differences up to 10% of the prescription dose are observed, which can lead to differences in the quality assertion of an implant. The study of individual patient edema resorption with time might be necessary to extract meaningful clinical correlation or biological parameters in permanent implants

  7. Nursing care for elderly lung cancer patients treated with CT-guided permanent interstitial co-implantation of 125I seeds and slow-released fluorouracil

    International Nuclear Information System (INIS)

    Objective: To investigate the specific measures and effect of the nursing care for elderly lung cancer patients who were receiving the treatment of CT-guided permanent interstitial co-implantation of 125I seeds and slow-released fluorouracil. Methods: Active care, including adequate preoperative preparation, proper support during operation and postoperative nursing,was carried out for fifty-three elderly patients with lung cancer during their treatment course of CT-guided permanent interstitial brachytherapy with co-implantation of 125I seeds and slow-released fluorouracil. Results: In order to ensure accurate puncture and the smooth particle implantation, the possible conditions which might happen after the procedure were informed to the patients before the surgery and useful advice was given to patients to guide their daily activities. All 53 patients showed no obvious fear before surgery and made good cooperation during the procedure, moreover, they well responded to the therapy and recovered pretty soon. Conclusion: CT-guided permanent interstitial co-implantation of 125I seeds and slow-released fluorouracil is a safe, minimally-invasive and newly-developed technique with reliable effect, which is especially suitable for aged patients. Active and adequate nursing care is essential during the whole therapeutic course. (authors)

  8. A Comparison of Acute and Chronic Toxicity for Men With Low-Risk Prostate Cancer Treated With Intensity-Modulated Radiation Therapy or 125I Permanent Implant

    International Nuclear Information System (INIS)

    Purpose: To compare the toxicity and biochemical outcomes of intensity-modulated radiation therapy (IMRT) and 125I transperineal permanent prostate seed implant (125I) for patients with low-risk prostate cancer. Methods and Materials: Between 1998 and 2004, a total of 374 low-risk patients (prostate-specific antigen 125I patients). Median follow-up was 43 months for IMRT and 48 months for 125I. The IMRT prescription dose ranged from 74-78 Gy, and 125I prescription was 145 Gy. Acute and late gastrointestinal (GI) and genitourinary (GU) toxicity was recorded by using a modified Radiation Therapy Oncology Group scale. Freedom from biochemical failure was defined by using the Phoenix definition (prostate-specific antigen nadir + 2.0 ng/ml). Results: Patients treated by using IMRT were more likely to be older and have a higher baseline American Urological Association symptom index score, history of previous transurethral resection of the prostate, and larger prostate volumes. On multivariate analysis, IMRT was an independent predictor of lower acute and late Grade 2 or higher GU toxicity and late Grade 2 or higher GI toxicity. Three-year actuarial estimates of late Grade 2 or higher toxicity were 2.4% for GI and 3.5% for GU by using IMRT compared with 7.7% for GI and 19.2% for GU for 125I, respectively. Four-year actuarial estimates of freedom from biochemical failure were 99.5% for IMRT and 93.5% for 125I (p = 0.09). Conclusions: The IMRT and 125I produce similar outcomes, although IMRT appears to have less acute and late toxicity

  9. Comparison of Dosimetric and Biologic Effective Dose Parameters for Prostate and Urethra Using 131Cs and 125I for Prostate Permanent Implant Brachytherapy

    International Nuclear Information System (INIS)

    Purpose: To compare the urethral and prostate absolute and biologic effective doses (BEDs) for 131Cs and 125I prostate permanent implant brachytherapy (PPI). Methods and Materials: Eight previously implanted manually planned 125I PPI patients were replanned manually with 131Cs, and re-planned using Inverse Planning Simulated Annealing. 131Cs activity and the prescribed dose (115 Gy) were determined from that recommended by IsoRay. The BED was calculated for the prostate and urethra using an ?/? ratio of 2 and was also calculated for the prostate using an ?/? ratio of 6 and a urethral ?/? ratio of 2. The primary endpoints of this study were the prostate D90 BED (pD90BED) and urethral D30 BED normalized to the maximal potential prostate D90 BED (nuD30BED). Results: The manual plan comparison (?/? = 2) yielded no significant difference in the prostate D90 BED (median, 192 Gy2 for both isotopes). No significant difference was observed for the nuD30BED (median, 199 Gy2 and 202 Gy2 for 125I and 131Cs, respectively). For the inverse planning simulated annealing plan comparisons (?/? 2), the prostate D90 BED was significantly lower with 131Cs than with 125I (median, 177 Gy2 vs. 187 Gy2, respectively; p = 0.01). However, the nuD30BED was significantly greater with 131Cs than with 125I (median, 192 Gy2 vs. 189 Gy2, respectively; p = 0.01). Both the manual and the inverse planning simulated annealing plans resulted in a significantly lower prostate D90 BED (p = 0.01) and significantly greater nuD30BED for 131Cs (p = 0.01), compared with 125I, when the prostate ?/? ratio was 6 and the urethral ?/? ratio was 2. Conclusion: This report highlights the controversy in comparing the dose to both the prostate and the organs at risk with different radionuclides

  10. A theoretical investigation into the role of tumour radiosensitivity, clonogen repopulation, tumour shrinkage and radionuclide RBE in permanent brachytherapy implants of 125I and 103Pd

    International Nuclear Information System (INIS)

    There is growing clinical interest in the use of 125I (half-life 59.4 days) and 103Pd (half-life 16.97 days) for permanent brachytherapy implants. These radionuclides pose interesting radiobiological challenges because, even with slowly growing tumours, significant tumour cell repopulation may occur during the long period taken to deliver the full radiation dose. This results in a considerable amount of the prescribed dose being wasted. There may also be changes in the tumour volume during treatment (due to oedema and/or shrinkage), thus altering the relative geometry of the implanted seeds and causing additional dose rate variations. This assessment examines the interaction between the above effects and additionally includes allowance for the influence of the relative biological effectiveness (RBE) of the radiations emitted by the two radionuclides. The results are presented in terms of the biologically effective doses (BEDs) and likely tumour control probabilities (TCPs) associated with the various parameter combinations. The overall BED enhancement due to the RBE effect is shown always to be greater than the RBE itself and is greatest in tumours which are radio-resistive and/or fast growing. The biological dose uncertainties are found to be less with 103Pd and the TCPs associated with this radionuclide are expected to be significantly higher in the treatment of some 'difficult' tumours. Using typically prescribed doses 125I appears to be better for treating radiosensitive tumours with long doubling times and which shrink fairly rapidly. However, unless 125I doses are reduced, this advantage may well be offset by the greatly enhanced biological doses delivered to adjacent normal structures. (author)

  11. Interactive-plan technique conquers the disadvantages of volume-reducing hormone therapy in 125I permanent implantation for localized prostate cancer

    International Nuclear Information System (INIS)

    The purpose of this study was to assess the impact of hormone therapy on post-implant dosimetry in patients in whom pre-plan and interactive-plan techniques were used for transperineal brachytherapy against prostatic cancer. The subjects comprised 244 patients treated using 125I seed implantation as monotherapy. The prescribed dose to the periphery of the prostate was 145 Gy. The pre-plan technique was used for 116 patients, and the interactive-plan technique for 128 patients. Hormone therapy was used in 71 patients (29.1%). The D90 (dose to 90% of prostate volume) of post-implant computed tomography (CT) analysis was assessed in both groups. In addition, the ratio of post-implant CT volume to preoperative ultrasonography (US) volume was assessed. In the pre-plan group, D90 was significantly lower for patients who received hormone therapy than for those who did not (P=0.035). However, in the interactive-plan group, D90 did not differ between patients with and without hormone therapy (P=0.467). The CT-to-US prostate volume ratio was 1.022 for patients who received hormone therapy and 0.960 for patients who did not (P=0.021). Post-traumatic swelling following implantation is increased by cessation of hormone therapy and may reduce D90. However, the present results suggest that the interactive-plan technique overcomes this disadvantage of hormone therapy. (author)

  12. Dosimetric and volumetric criteria for selecting a source activity and a source type (125I or 103Pd) in the presence of irregular seed placement in permanent prostate implants

    International Nuclear Information System (INIS)

    Purpose: The dosimetric merit of a permanent prostate implant relies on two factors: the quality of the plan itself, and the fidelity of its implementation. The former factor depends on source type and on source strength, while the latter is a combination of skill and experience. The purpose of this study is to offer criteria by which to select a source type (125I or 103Pd) and activity. Methods and Materials: Given a prescription dose and potential seed positions along needles, treatment plans were designed for a number of seed types and activities, specifically for 125I with activities ranging from 0.3 to 0.7 mCi, and for 103Pd with activities in the range of 0.8 to 1.6 mCi. To avoid human planner bias, an automated computerized planning system based on integer programming was used to obtain optimal seed configurations for each seed type and activity. To simulate the effect of seed-placement inaccuracies, random seed-displacement 'errors' were generated for all plans. The displacement errors were assumed to be uniformly distributed within a cube with side equal to 2no. sigmano. The resulting treatment plans were assessed using two volumetric and two dosimetric indices. Results: For 125I implants a coverage index (CI) of 98.5% or higher can be achieved for all activities (CI is the fraction of the target volume receiving the prescribed or larger dose). The external volume index (EI) (i.e., the amount of healthy tissue, as percentage of the target volume, receiving the prescribed or larger dose) increases from 13.9% to 20% as the activity increases from 0.3 to 0.7 mCi. For implants using 103Pd, the external volume index increases from 10.2% to 13.9% whenever CI exceeds 98.5%. Volumetric and dosimetric indices (coverage index, external volume index, D90, and D80) are all sensitive to seed displacement, although the activity dependence of these indices is more pronounced for 125I than for 103Pd implants. Conclusions: For both isotopes, the lower activities studied systematically result in lower EIs. If seeds can be placed within approximately 0.5 cm of their intended position 103Pd should be preferred because its EI is lower than that of 125I. For all activities the coverage indices and D90 are within the required range. If seed placement uncertainties are larger than 0.5 cm, 125I provides slightly better target coverage; however, in terms of external volume (healthy tissue) covered, 103Pd is superior to 125I

  13. Implant quality and acute urinary toxicity with 125I permanent seed implantation for clinically localized prostate cancer. Results of the first 30 patients treated at PMCC

    International Nuclear Information System (INIS)

    It is widely recognized that a steep learning curve exists for departments initiating a prostate low-dose radiation (LDR) implant service. Appropriate team credentialing, willingness to accept mentoring and attention toward ongoing QA initiatives are required to ensure that both clinical and dosimetric endpoints consistently achieve standards deemed appropriate. The department of urological services began a prostate seed service in 4/2002. All participating staff were suitably trained in Seattle, Washington with unit protocols based on standard trans-rectal sonographic pre-planning, modified peripheral loading, prescription dose 145Gy and 4 week CT based post implant dosimetry. Patient eligibility paralleled federal medicare guidelines with men presenting with favorable risk disease, gland volumes 15ml/sec) considered potential candidates. a) Presenting Demographics: (n=30) Median age 62 (41-73), T stage 1c:2a:2b:2c = 18:10:1:1, Median PSA 6.3ng/ ml (5.1ng/ml - 11.1ng/ml), Median IPSS 5 (0-12), Mean Qmax 18ml/s (10ml/s -35ml/s).; b) Acute toxicity: No significant peri-procedural complications. One patient developed urinary retention day 3 and was successfully trialed day 10. All patients experienced some degree of sub-acute urinary irritation although three patients followed for at least 12 months have returned to their baseline level of functioning. c) Post implant Dosimetry: Median D90 139Gy (104Gy - 190Gy). 3 Patients received a D90 < 90% with one at 104Gy receiving additional 'top-up' external beam radiation (20Gy). A definable improvement in implant quality was observed over the 12 month study interval. Although acute toxicity was considered acceptable, patients do experience a sub-acute period of low grade albeit persistent urinary irritation and need to be cautioned appropriately. A high level of implant quality was achieved in the majority of patients. Despite 5 years HDR brachytherapy experience, considerable refinement in technique and approach was required in order to achieve consistent high level results

  14. The clinical application of 125I radionuclide implantation in tumor therapy

    International Nuclear Information System (INIS)

    Objective: To investigate the safely and clinical efficacy of permanent implantation of 125I radioactive particle in the surgery of malignancies such as brain tumors, liver cancer, cholangiocarcinoma, lung cancer, prostate cancer and malignant teratoma. Methods: Thirty eight patients proved by puncture biopsy, histology or cytology were retrospectively analyzed. Three-D images of the tumor were reconstructed using treatment planning system (TPS), the number and the dose rate distribution of 125I seeds were calculated. The matched peripheral dose of 125I seeds implantation was 60?130 Gy, the number of 125I seeds implanted ranged from 6?40 per lesion, and the median amount of implanted 125I seeds were 23. Results: Twelve months followup after the therapy showed 9 cases of complete relief, 24 cases of partial relief and 5 cases of no change. The overall effective rate (complete relief + partial relief) of 12 months was 86.8%. Conclusion: Permanent implantation of 125I radioactive particle in the surgery of malignancies treatment is a safe, effective treatment for tumors. (authors)

  15. Radiation protective nursing intervene of 125I seed implantation in non-small cell lung cancer

    International Nuclear Information System (INIS)

    Lung cancer is the most common primary malignant tumor. Because most sufferers have already been in later stage in their first diagnosis, the lump body infringing upon the important organs often influences the excision of tumor. 125I seeds permanent implantation is a new method for tumor brachytherapy, which contributes to kill the tumor completely, ensures the normal physiological functions of organs,reduces tissue injuries and treatment of complications, and raises the survival rate of sufferers. The rapid promotion of this technique is also followed by radiation risks in the treatment. Currently, the researches of 125I seeds implantation is limited to the aspects of treatment means and effects, with no detailed study in intraoperative usage, disinfection and protection. Although a satisfactory curative effect is the key in the treatment,the studies in protection principles, means and technological upgradation are also too important to be ignored. (authors)

  16. Efficacies of 125I seed implantation in advanced stage central lung cancer via fibrobronchoscope

    International Nuclear Information System (INIS)

    Objective: To explore the temporal curative effect of 125I seed implantation in advanced stage central type lung cancer. Methods: 125I seed was implanted in 56 patients confirmed advanced stage central type lung cancer via fibrobronchoscope and all cases were fellow up in certain duration to explore their efficacies and the adverse reaction. Results: Total efficient rate was 76.78% in 56 patients. Lung reexpanded rate was 90.90%. Conclusion: The therapy of 125I seed implantation in advanced stage central type lung cancer is safe and available. (authors)

  17. The use of anisotropic data in 125I prostate implants

    International Nuclear Information System (INIS)

    The report recently published by the American Association of Physicists in Medicine (AAPM) Task Group 43 (TG43) recommends the use of a two dimensional dose distribution function for the dosimetry associated with 125I, 192Ir and 103Pd sources. For commercial planning systems that cannot be readily adapted to use a two dimensional function, a point source approximation is provided. The dose distribution around an array of 125I seeds has been calculated using the two dimensional model and the point source approximation. Isodose distributions through selected planes and dose volume histograms of selected cubic volumes show that differences between the two models for this array are insignificant, particularly in view of the uncertainties associated with using the data which is provided by TG43 for the two dimensional anisotropy function and that it should be retained for planning prostrate treatments with 125I seeds. It is recommended that each application must be examined separately to establish the extent to which an isotropic dose distribution is applicable

  18. Comparison of 3 different postimplant dosimetry methods following permanent 125I prostate seed brachytherapy

    International Nuclear Information System (INIS)

    Postimplant dosimetry (PID) after Iodine-125 (125I) implant of the prostate should offer a reliable qualitative assessment. So far, there is no consensus regarding the optimum PID method, though the latest literature is in favor of magnetic resonance imaging (MRI). This study aims to simultaneously compare 3 PID techniques: (1) MRI-computed tomography (CT) fusion; (2) ultrasound (US)-CT fusion; and (3) manual target delineation on CT. The study comprised 10 patients with prostate cancer. CT/MR scans with urinary catheters in place for PID were done either on day 0 or day 1 postimplantation. The main parameter evaluated and compared among methods was target D90. The results show that CT-based D90s are lower than US-CT D90s (median difference,?6.85%), whereas MR-CT PID gives higher D90 than US-CT PID (median difference, 4.25%). Manual contouring on CT images tends to overestimate the prostate volume compared with transrectal ultrasound (TRUS) (median difference, 23.33%), whereas on US images the target is overestimated compared with MR-based contouring (median difference, 13.25%). Although there are certain differences among the results given by various PID techniques, the differences are statistically insignificant for this small group of patients. Any dosimetric comparison between 2 PID techniques should also account for the limitations of each technique, to allow for an accurate quantification of data. Given that PID after permanent radioactive seed implant is mandatory for quality assurance, any imaging method–based PID (MR-CT, US-CT, and CT) available in a radiotherapy department can be indicative of the quality of the procedure

  19. Comparison of 3 different postimplant dosimetry methods following permanent {sup 125}I prostate seed brachytherapy

    Energy Technology Data Exchange (ETDEWEB)

    Marcu, Loredana G., E-mail: loredana@marcunet.com [Department of Medical Physics, Royal Adelaide Hospital, South Australia (Australia); Faculty of Science, University of Oradea (Romania); School of Chemistry and Physics, University of Adelaide, South Australia (Australia); Gowda, Raghu [Department of Radiation Oncology, Royal Adelaide Hospital, South Australia (Australia)

    2013-10-01

    Postimplant dosimetry (PID) after Iodine-125 ({sup 125}I) implant of the prostate should offer a reliable qualitative assessment. So far, there is no consensus regarding the optimum PID method, though the latest literature is in favor of magnetic resonance imaging (MRI). This study aims to simultaneously compare 3 PID techniques: (1) MRI-computed tomography (CT) fusion; (2) ultrasound (US)-CT fusion; and (3) manual target delineation on CT. The study comprised 10 patients with prostate cancer. CT/MR scans with urinary catheters in place for PID were done either on day 0 or day 1 postimplantation. The main parameter evaluated and compared among methods was target D90. The results show that CT-based D90s are lower than US-CT D90s (median difference,?6.85%), whereas MR-CT PID gives higher D90 than US-CT PID (median difference, 4.25%). Manual contouring on CT images tends to overestimate the prostate volume compared with transrectal ultrasound (TRUS) (median difference, 23.33%), whereas on US images the target is overestimated compared with MR-based contouring (median difference, 13.25%). Although there are certain differences among the results given by various PID techniques, the differences are statistically insignificant for this small group of patients. Any dosimetric comparison between 2 PID techniques should also account for the limitations of each technique, to allow for an accurate quantification of data. Given that PID after permanent radioactive seed implant is mandatory for quality assurance, any imaging method–based PID (MR-CT, US-CT, and CT) available in a radiotherapy department can be indicative of the quality of the procedure.

  20. Comparison of 3 different postimplant dosimetry methods following permanent 125I prostate seed brachytherapy.

    Science.gov (United States)

    Marcu, Loredana G; Gowda, Raghu

    2013-01-01

    Postimplant dosimetry (PID) after Iodine-125 ((125)I) implant of the prostate should offer a reliable qualitative assessment. So far, there is no consensus regarding the optimum PID method, though the latest literature is in favor of magnetic resonance imaging (MRI). This study aims to simultaneously compare 3 PID techniques: (1) MRI-computed tomography (CT) fusion; (2) ultrasound (US)-CT fusion; and (3) manual target delineation on CT. The study comprised 10 patients with prostate cancer. CT/MR scans with urinary catheters in place for PID were done either on day 0 or day 1 postimplantation. The main parameter evaluated and compared among methods was target D90. The results show that CT-based D90s are lower than US-CT D90s (median difference,-6.85%), whereas MR-CT PID gives higher D90 than US-CT PID (median difference, 4.25%). Manual contouring on CT images tends to overestimate the prostate volume compared with transrectal ultrasound (TRUS) (median difference, 23.33%), whereas on US images the target is overestimated compared with MR-based contouring (median difference, 13.25%). Although there are certain differences among the results given by various PID techniques, the differences are statistically insignificant for this small group of patients. Any dosimetric comparison between 2 PID techniques should also account for the limitations of each technique, to allow for an accurate quantification of data. Given that PID after permanent radioactive seed implant is mandatory for quality assurance, any imaging method-based PID (MR-CT, US-CT, and CT) available in a radiotherapy department can be indicative of the quality of the procedure. PMID:23611630

  1. CT-Guided Radioactive 125I Seed Implantation Therapy of Symptomatic Retroperitoneal Lymph Node Metastases

    International Nuclear Information System (INIS)

    PurposeThis study explored the clinical efficacy of CT-guided radioactive 125I seed implantation in treating patients with symptomatic retroperitoneal lymph node metastases.MethodsTwenty-five patients with pathologically confirmed malignant tumors received CT-guided radioactive 125I seed implantation to treat metastatic lymph nodes. The diameter of the metastatic lymph nodes ranged from 1.5 to 4.5 cm. Treatment planning system (TPS) was used to reconstruct the three-dimensional image of the tumor and then calculate the corresponding quantity and distribution of 125I seeds.ResultsFollow-up period for this group of patients was 2–30 months, and median time was 16 months. Symptoms of refractory pain were significantly resolved postimplantation (P 125I seed implantation, which showed good palliative pain relief with acceptable short-term effects, has proved in our study to be a new, safe, effective, and relatively uncomplicated treatment option for symptomatic retroperitoneal metastatic lymph nodes

  2. CT-guided radioactive 125I seed implantation treatment of multiple pulmonary metastases of hepatocellular carcinoma

    International Nuclear Information System (INIS)

    Aim: To investigate the clinical value of computed tomography (CT)-guided radioactive 125I seed implantation for the treatment of multiple pulmonary metastases of hepatocellular carcinoma (HCC). Materials and methods: From March 2007 to August 2010, 27 HCC patients with pulmonary metastases who had received computed tomography (CT)-guided radioactive 125I seed implantation were enrolled in the study. All patients had ?2 metastatic lesions (mean diameter 2 ± 0.6 cm). Under CT-guidance, 125I seeds were implanted into the pulmonary metastases using the plane implantation technique. Results: Among 27 cases, complete response, partial response, stable disease, and progressive disease were observed in four, 15, six, and two cases, respectively, during 6–48 months (mean 20.1 ± 2.2 months) of follow-up CT. The response rate was 92.6%. The mean follow-up time after 125I implantation was 20.1 months (range 6–48 months). The survival rates at 1 and 2 years were 67% and 30.8%, respectively, with a median survival of 13.5 months. Side effects during the procedure included minor pulmonary effusions and pneumothorax. Pulmonary haemorrhage was observed in 18 cases and haemoptysis occurred in five patients. Radial shadows were observed in three cases on follow-up CT images, and seed migration in two cases on follow-up spiral CT images. Conclusion: CT-guided radioactive 125I seed implantation may be a safe and effective treatment option for HCC patients with multiple pulmonary metastases. - Highlights: • HCC patients with pulmonary metastases received CT-guided radioactive 125I seed implantation. • CT-guided radioactive 125I seed implantation may be a safe and effective treatment option. • Prospective studies are needed to confirm its value

  3. Evaluation of 125I seed implantation combined with arterial infusion chemotherapy in treating unresectable lung cancer

    International Nuclear Information System (INIS)

    Objective: To assess the therapeutic effect of CT-guided 125I seed implantation combined with arterial infusion chemotherapy in treating unresectable lung cancer. Methods: Thirty patients with unresectable non-small call lung cancer were randomly divided into two groups. Group A (study group,n = 14)was receiving arterial infusion chemotherapy one week before and one week after 125I seed implantation. Group B (control group, n = 16) was receiving 125I seed implantation only. Two months after 125I seed implantation, follow-up checkup with thoracic CT scanning was carried out in all patients. The response to treatment was evaluated in accordance with RECIST criteria and the accumulated survival rate was analyzed by means of Kaplan-Meier. Results: Scheduled treatment was completed in all 30 patients. Under CT-guidance, 552 125I seeds were implanted in the patients of group A, while 603 125I seeds were implanted in the patients of group B. Nine patients in group A received two times of arterial infusion chemotherapy. Follow-up CT examination showed that the case number of complete remission, partial remission,stabilized disease and progressive disease in group A was 0, 10, 4 and 0 respectively, with an overall response rate of 71.43%. The corresponding data in group B was 0, 10, 5 and 1 respectively, with an overall response rate of 62.5%. The difference in the response rate between two groups was of no statistical significance (P > 0.05). The one-year survival rate of group A and B was 78.6% and 62.5% respectively, the difference between the two groups was statistically significant (P 125I seed implantation combined with arterial infusion chemotherapy is an effective treatment for unresectable lung cancer, it can significantly prolong the patient's survival time. (authors)

  4. Efficacy of CT guided radioactive 125I seed implantation in the treatment of lung cancer

    International Nuclear Information System (INIS)

    Objective: To investigate the feasibility, efficacy and complications of CT guided radioactive 125I seed implantation in the treatment of lung cancer. Methods: According to the different treatment methods, 65 patients with lung cancer were divided into two groups, 37 cases in the implantation alone group received CT guided 125I seeds interstitial implantation, the other 28 cases in the combination treatment group received interstitial 125I seeds implantation combined with chemotherapy. All the patients were examined by posologic validation, and were followed up termly. Results: The total effective rate of 65 patients was 80.0%, 1-year survival rate was 90.8%. The effective rates of implantation alone group and combination treatment group were 67.6% and 96.4% respectively. There was a significant difference between the two groups (?2=8.298, P<0.01). Before treatment, all the patients' mean diameter of the tumor was 5.48 cm; while it was 3.77 cm after treatment (t=7.764, P<0.01). Complications included pneumothorax (36 cases), bloody sputum (7 cases), fever (4 cases) which improved after treatment in 65 patients,but without radiation pneumonia. Conclusion: 125I seed implantation is a highly effective treatment without severe complications in the treatment of lung cancer. (authors)

  5. CT guided interstitial 125I seed implantation treatment of refractory lung cancer

    International Nuclear Information System (INIS)

    Objective: To evaluate the clinical value of CT guided interstitial 125I seed implantation treatment of refractory lung cancer. Methods: A total of 35 cases of refractory lung cancer patients underwent 125I seed implantation treatment. Preoperative treatment planning system was used to calculate the distribution of radioactive source, then 2.855-3.087 MBq 125I seeds were implanted into the tumor tissues intraoperatively. Plane implantation of the particles were made every 0.5-1.0 cm. Matched peripheral dose was 150-180 Gy, and 10-130 particles were implanted for each patient, who would be followed up by CT to explore their efficacies two months later. Results: Of the 35 patients, there were complete remission 4 cases,partial remission 27 cases, stable disease 3 cases, and progressive disease 1 cases. The objective response rate was 88.57%. Serious intraoperative and postoperative pneumothorax occurred in 5 patients, among whom transference cure was found 3-10 days later after their closed thoracic drainage, and 7 mild pneumothorax patients healed without more treatment. After follow-up it was found that most toxic reactions were mild and tolerable, and no severe complications were reported like hemoptysis or radiation pneumonia. Conclusion: It is effective, less inasie and of low complication rate in CT guided interstitial 125I seed implantation treatment of advanced refractory lung cancer. (authors)

  6. The NCI-atlas of dose distributions for regular 125I brain implants

    International Nuclear Information System (INIS)

    In connection with the development of an optimization method for 125I brain implants in irregulary shaped target volumes, a systematic study was conducted toward optimizing seed configurations for regular target volumes. The intention was to find basic rules for the positioning of strings of seeds in the cylindrical implant pattern of the stereotactic neurosurgical procedure in use, and in accordance with the following criteria: (i) steep dose fall-off outside the target volume; (ii) coverage of the target volume by making the prescribed dose surface coincident with the target volume surface within 1 mm; (iii) uniformity of the dose distribution in the target volume as far as achievable with a seed implant. As a result of this study, an atlas of optimized angular 125I brain implant configurations was compiled. Regular implants were understood as being cylindrical or spherical. Diameters and heights from 2 to 5 cm were covered. 8 refs.; 11 figs.; 2 tabs

  7. The clinic application of CT-guided interstitial 125I seeds implantation in curing lung cancer

    International Nuclear Information System (INIS)

    Objective: To introduce the procedures and evaluate the clinic value of CT-guided interstitial 125I seeds implantation in treating lung cancer. Methods: Thirty-one cases patients with lung cancer underwent CT-guided interstitial 125I seeds implantation. All patients were scanned on multi-spiral CT (Philips, MX 8000) with optical navigating system (pinpoint), and treatment plan system, needle, and 125I seeds (Chinese Academy of Science) were used. First of all, according to the size of tumor, TPS calculated the optimal quantity of seeds. Then, under the guidance of CT, 125I seeds were percutaneously implanted into the tumors for interstitial radiotherapy. CT follow-up examinations were performed 1, 2, and 6 months after the therapy, respectively. According to the size of tumor, curative effects were graded as 4 grades: grade I: obvious relief (OR) (the size of tumor reduced up to 50%), grade II: relief (PR) (the size of tumor reduced by 25%-50%), grade III: slight relief (SD) (the size of tumor reduced by 1%-25%), and grade IV: no effect (PD) (the size of tumor did not reduce or increase, and clinic symptoms showed no relief). Results: At 1 month, 9 cases were classified as grade I, 6 as grade II, 13 as grade III, and 3 as grade IV, respectively. At 2 months, 17 cases were grade I, 8 grade II, 3 grade III, and 3 grade IV, respectively. At 6 months, 23 cases were grade I, 3 grade II, 2 grade III, and 3 grade IV, respectively. Conclusion: CT-guided interstitial 125I seeds implanted was a safe, reliable, and effective curative method for lung cancer. (authors)

  8. Clinical efficacy of CT-guided 125I seed implantation therapy for advanced lung cancer

    International Nuclear Information System (INIS)

    Objective: To investigate the safety and clinical efficacy of CT-guided radioactive 125I seed implantation treatment for advanced lung cancer. Methods: The clinical data of thirty cases with lung cancer, which was proved by puncture biopsy, histology or cytology, were retrospectively analyzed. The pathologic diagnoses included squamous cell carcinoma (n=13), adenocarcinoma (n=8) and metastatic lung cancer (n=9). Using treatment planning system (TPS) 3D images of the tumor were reconstructed, the number and the dose rate distribution of 125I seeds were calculated. The matched peripheral dose (MPD) of 125I seed implantation was 80-130 Gy. The median amount of implanted 125I seeds was 35 (8 - 83) in number. Results: Follow-up observation was made at 1, 3, 6 and 12 months after the treatment in all patients. The median survival time was 12 months (7-18 months). The cumulative survival rate at 6, 9 and 12 months was 100.0%, 80.0% and 23.3%, respectively. Follow-up CT images 12 months after the therapy showed that complete relief (CR) was seen in 9 cases, partial relief (PR) in 14 cases, no change (NC) in 4 cases and progression (PD) in 3 cases. The overall effective rate (CR + PR) of 1-month, 3- month, 6-month and 12-month was 83%, 80%, 80% and 77%, respectively. During following-up period, pneumothorax occurred in 3 cases and bloody sputum occurred in 7 cases. Conclusion: CT-guided radioactive 125I seed implantation treatment is a safe, effective and minimally-invasive treatment for lung cancer. (authors)

  9. CT-guided 125I Radioactive Seed Implantation on Regional Lymph Node Metastasis after Gastrectomy

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    Liangrong Shi

    2013-09-01

    Full Text Available Objective: To evaluate the safety and short-term effect of CT-guided 125I radioactive seed implantation on regional lymph node metastasis after gastrectomy. Methods: Twenty-three patients with regional lymph node metastasis after gastrectomy received CT-guided 125I radioactive seed implantation from June, 2007 to July, 2011 in our hospital. The overall activity and amount of radioactive seeds were calculated by simulating source distribution of radioactive seed implantation plan system before operation. 125I seeds were implanted under the guidance of CT. Effective rate was evaluated according to RECIST criterion, 1, 2 and 3 years of survival rates were calculated by life table method, the effect of relative factors on survival was tested by univariate COX model, and the survival differences between subgroups were compared to draw survival curve by log-rank method. Additionally, systemic therapies were given to 20 patients based on fluorouracil drugs. Results: No severe complications was observed in all study subjects with 14 complete remission (60.9 ? , 5 particle remission (21.7 ? and 4 progressive diseases (17.4 ? , while 1, 2 and 3 years of survival rates as well as median survival time being (87±7 ??(47±11 ? , (13±9 ? and (22.1±5.1 months, respectively. Univariate COX analysis showed that the maximum diameter of tumor could badly influence the prognosis (?2 ? 9.752, P ? 0.002, and the subgroups analysis relieved the significant difference (?2 ? 5.828, P ? 0.016, log-rank test with 3 cm being the cut-off value. Conclusion: CT-guided 125I radioactive seed implantation has high local control rate with small trauma and slight complications.

  10. Permanent 125I-seed prostate brachytherapy: early prostate specific antigen value as a predictor of PSA bounce occurrence

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    Mazeron Renaud

    2012-03-01

    Full Text Available Abstract Purpose To evaluate predictive factors for PSA bounce after 125I permanent seed prostate brachytherapy and identify criteria that distinguish between benign bounces and biochemical relapses. Materials and methods Men treated with exclusive permanent 125I seed brachytherapy from November 1999, with at least a 36 months follow-up were included. Bounce was defined as an increase ≥ 0.2 ng/ml above the nadir, followed by a spontaneous return to the nadir. Biochemical failure (BF was defined using the criteria of the Phoenix conference: nadir +2 ng/ml. Results 198 men were included. After a median follow-up of 63.9 months, 21 patients experienced a BF, and 35.9% had at least one bounce which occurred after a median period of 17 months after implantation (4-50. Bounce amplitude was 0.6 ng/ml (0.2-5.1, and duration was 13.6 months (4.0-44.9. In 12.5%, bounce magnitude exceeded the threshold defining BF. Age at the time of treatment and high PSA level assessed at 6 weeks were significantly correlated with bounce but not with BF. Bounce patients had a higher BF free survival than the others (100% versus 92%, p = 0,007. In case of PSA increase, PSA doubling time and velocity were not significantly different between bounce and BF patients. Bounces occurred significantly earlier than relapses and than nadir + 0.2 ng/ml in BF patients (17 vs 27.8 months, p Conclusion High PSA value assessed 6 weeks after brachytherapy and young age were significantly associated to a higher risk of bounces but not to BF. Long delays between brachytherapy and PSA increase are more indicative of BF.

  11. CT-guided 125I radioactive seeds implantation and chemical ablation for malignant retroperitoneal tumors

    International Nuclear Information System (INIS)

    Objective: To explore the clinical value of CT-guided 125I radioactive seeds implantation and chemical ablation for malignant retroperitoneal tumors. Methods: Because of the rejection of the second surgery resection and insensitivity of chemotherapy and radiotherapy, nineteen patients with recurrent or metastasis malignant retroperitoneal tumors were treated by CT-guided 125I radioactive seeds implantation according to TPS or Halarism's experienced function, and percutaneous ethanol injection was performed if the way of punctuation was limited. The extent of pain relief was assessed one month later after therapy. All the patients received enhanced CT scan 6 months after the first treatment, and imaging evaluation was performed according to WHO criteria. Results: For the 19 patients, pain relief was achieved more or less in all patients. Imaging evaluation revealed complete relief, partial relief, no change in 10, 7, 2 cases respectively. All patients are still alive now. The longest followed span is 31 months, and the shortest is 7 months, the average followed span is 13.5 months. Conclusion: CT-guided 125I radioactive seeds implantation and chemical ablation are effective for malignant retroperitoneal tumors. (authors)

  12. 125I seed implant brachytherapy for the treatment of parotid gland cancers in children and adolescents

    International Nuclear Information System (INIS)

    Background and purpose: There is a lack of optimal treatment strategies for managing salivary gland cancers in children and adolescents. This study is aimed at assessing the effect of 125I seed implantation for the treatment of parotid cancers in children and adolescents. Patients and methods: A total of 12 patients younger than 16 years with parotid gland malignant tumors underwent 125I seed implant brachytherapy between October 2003 and November 2008. All patients were assessed after treatment and at the local tumor control appointments. Facial nerve function, maxillofacial development, and radioactive side-effects were assessed. Results: The follow-up period ranged from 41-104 months. One patient with T4b died of pulmonary metastasis. The other patients were alive during the follow-up period. There were no serious radiation-related complications. The treatment did not affect facial nerve function and dentofacial growth in any of the children. Conclusion: For parotid gland cancers in children, 125I seed implant brachytherapy may be an acceptable treatment without serious complications and with satisfactory short-term effects. (orig.)

  13. Clinical effect observation of 125I seed implantation combined with endocrinal therapy for prostate cancer

    International Nuclear Information System (INIS)

    Objective: To retrospectively study the efficacy and side-effect of 125I seed implantation combined with endocrinal therapy in stage T3N0M0 prostate cancer. Methods: The study included 22 patients with clinical stage T3N0M0 prostate cancer who were treated with transperineal 125I seed implantation guided by transrectal ultrasound, real time TPS and endocrinal therapy. The minimum peripheral doses (MPD) were 140-160 Gy. The median number of seeds was 74(26-90). The activity of each seed was 1.55 × 107 (1.30 × 107-1.85 × 107) Bq. 11 patients were treated with orchidectomy, and 11 patients were treated with androgen deprivation therapy. Results: All 22 patients completed the seed implantation successfully. The 5-year biochemical progression-free survival was 70.6%, and 5-year overall survival was 81.8%. 2 patients were found biochemical failure in 12 months after seed implantation, and another 1 patient failed in 90 months. Endocrinal therapy was followed thereafter. After the seed implantation, the urinary complications of grade 1 and 2 were 54.5% and 9.1% respectively, and the rectum side-effect of grade 1 and 2 were 22.7% and 9.1%.1 patient suffered rectal complication of grade 4. Conclusions: Good effect and tolerance are observed in prostate cancer patients of stage T3N0M0 receiving 125I seed implantation plus endocrinal therapy.The treatment can be considered for those who refuse to receive external beam radiotherapy. (authors)

  14. CT-Guided Radioactive {sup 125}I Seed Implantation Therapy of Symptomatic Retroperitoneal Lymph Node Metastases

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    Wang, Zhongmin, E-mail: wzm0722@hotmail.com [Shanghai Jiaotong University School of Medicine, Department of Nuclear Medicine, Renji Hospital (China); Lu, Jian; Gong, Ju; Zhang, Liyun [Shanghai Jiaotong University School of Medicine, Department of Radiology, Ruijin Hospital Luwan Branch (China); Xu, Yingjia [Shanghai Jiao Tong University, Department of Cardiology, Shanghai Chest Hospital (China); Song, Shaoli [Shanghai Jiaotong University School of Medicine, Department of Nuclear Medicine, Renji Hospital (China); Chen, Kemin [Shanghai Jiaotong University School of Medicine, Department of Radiology, Ruijin Hospital (China); Liu, Fenju [Soochow University, School of Radiation Medicine and Public Health (China); Gang, Huang, E-mail: huanggang0722@hotmail.com [Shanghai Jiaotong University School of Medicine, Department of Nuclear Medicine, Renji Hospital (China)

    2013-04-12

    PurposeThis study explored the clinical efficacy of CT-guided radioactive {sup 125}I seed implantation in treating patients with symptomatic retroperitoneal lymph node metastases.MethodsTwenty-five patients with pathologically confirmed malignant tumors received CT-guided radioactive {sup 125}I seed implantation to treat metastatic lymph nodes. The diameter of the metastatic lymph nodes ranged from 1.5 to 4.5 cm. Treatment planning system (TPS) was used to reconstruct the three-dimensional image of the tumor and then calculate the corresponding quantity and distribution of {sup 125}I seeds.ResultsFollow-up period for this group of patients was 2–30 months, and median time was 16 months. Symptoms of refractory pain were significantly resolved postimplantation (P < 0.05), and Karnofsky score rose dramatically (P < 0.05). Most patients reported pain relief 2–5 days after treatment. Follow-up imaging studies were performed 2 months later, which revealed CR in 7 patients, PR in 13 patients, SD in 3 patients, and PD in 2 patients. The overall effective rate (CR + PR) was 80 %. Median survival time was 25.5 months. Seven patients died of recurrent tumor; 16 patients died of multiorgan failure or other metastases. Two patients survived after 30 months follow-up. Two patients reported localized skin erythema 1 week postimplantation, which disappeared after topical treatment.ConclusionsCT-guided radioactive {sup 125}I seed implantation, which showed good palliative pain relief with acceptable short-term effects, has proved in our study to be a new, safe, effective, and relatively uncomplicated treatment option for symptomatic retroperitoneal metastatic lymph nodes.

  15. Pathological impairments induced by interstitial implantation of 125I Seeds in spinal canal of banna mini-pigs

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    Yang Zuozhang

    2012-03-01

    Full Text Available Abstract Background Use a banna mini-pig to set up 125I implantation model, and investigate the consequence of radiation-related impairments. Methods In present study, 125I seeds were implanted into spinal canal of T13 level of spine in banna mini-pigs. After operation, the pigs were raised up to 8 months, behavior changes were recorded within this period. After 8 months, spinal cords were collected for pathological analysis. Results In this study, a 125I brachytherapy animal model had been successfully established, in the model group, the banna pigs' Tarlov scale decreased from 5 to 2.57 ± 0.36, significant cellular impairments were noted by pathological analysis. Conclusions Without any protection and operation improvement, 125I implantation can cause serious histological impairments and moving difficulty for banna mini-pigs; this present research provides an alternative tool to study spinal 125I brachytherapy.

  16. Linear 125I seeds strand implantation combined with biliary stenting for the treatment of malignant biliary obstruction

    International Nuclear Information System (INIS)

    Objective: To evaluate the therapeutic efficacy of linear 125I seeds strand implantation combined with biliary stenting in treating malignant biliary obstruction. Methods: Linear 125I seeds strand implantation combined with biliary stenting was carried out in 28 patients with malignant biliary obstruction. The technical success rate, the clinical efficacy, the postoperative complications and the survival rate were analyzed. Results: Both biliary stenting and 125I seeds strand implantation were successfully accomplished in all patients. No serious complications occurred. After the procedure the biliary obstruction symptoms were markedly improved and the bilirubin level was significantly reduced (P125I seeds strand implantation together with biliary stenting is safe and effective although its long-term efficacy needs to be further studied. (authors)

  17. The clinical application of TACE together with RFA and 125I seed implantation in treating hepatocellular carcinoma

    International Nuclear Information System (INIS)

    Objective: to assess the clinical value of the combined treatment of transcatheter arterial chemoembolization (TACE), CT-guided radiofrequency ablation (RFA) and radioactive 125I seed implantation for hepatocellular carcinoma (HCC). Methods: During the period from March 2008 to Dec. 2010, 15 patients with HCC were admitted to the hospital. A total of 25 hepatic lesions were detected with the size of 1-8 cm. TACE was carried out first, which was followed by CT-guided RFA and radioactive 125I seed implantation. With the help of treat plan system (TPS), the radioactive 125I seed implantation was conducted to make additional management for the same lesion when RFA was finished, or the radioactive 125I seeds were directly implanted into the areas where RFA could not reach. The radioactive dose was 60-100 Gy. All the patients were followed up and were kept under observation for the signs of related complications. The therapeutic results were evaluated. Results: The combined treatment was successfully accomplished in all patients. All patients were followed up for 3-28 months (mean of 10.6 months). The complete necrosis rate of the tumor was 96%. No serious complications occurred except the immigration of 125I seeds in 1 case. Conclusion: The combined treatment of TACE and CT-guided RFA together with 125I seed implantation is a safe, reliable and effective therapy for HCC with excellent short-term result. (authors)

  18. Radiation safety and protection of close contacts from radiators after implantation of radioactive 125I seeds

    International Nuclear Information System (INIS)

    Objective: To study the effective dose and precaution time of the irradiation of the close contact from the radiators who underwent implantation of radioactive 125I seeds so as to guide scientifically people how to avoid radiation damage. Methods: Twenty patients with different types of cancer underwent implantation of radioactive 125I seeds with the median value of implantation depth of 2.16 cm. Within 24 h after the operations the dose rates 30 cm and 100 cm from the skin were measured with pocket-size radiometer so as to imitate the situations of the close contacts. The effective doses and precaution times of different persons were calculated according to relevant formula. Results: The dose rate a person received at the same time points (1, 54, 78, and 109 d, respectively) decreased along with the increase of the distance from the skin (t=5.962, 5.961, 5.961, 5.962, P<0.05), and the dose rate a person received at the same distance from the skin decreased along with the extension of time (30 cm: t=6.236, 6.236, 6.235, P<0.05; 100 cm: t=7.310, 7.315, 7.314, P<0.05). At different time points, the dose rates at 30 cm distance point were all significant higher than those at the 100 cm point (P <0.05). The adult living together, minors and pregnant women sharing the room, colleagues,adults who slept together with the patients began to reach the 50% dose constraint values 0, 54, 78 and 109 days after the operation. Conclusions: After their precaution time, it's safe to contact with the patients for the groups; otherwise, it's necessary to take some protect works within the precaution time. (authors)

  19. Radioactive seed 125I implantation plus Gemcitabine in treatment for peripheral non-small cell lung cancer

    International Nuclear Information System (INIS)

    Objective: To investigate the clinical value of radioactive seed 125I implantation combined with Gemcitabine (GEM)in treatment for peripheral non-small cell lung cancer(NSCLC). Methods: 60 patients (male 35, female 27, mean age 73.3) with peripheral lung carcinoma were confirmed under CT-guided biopsy including 8 bronchoalveolar carcinomas and 17 squamous carcinomas, 6 in the stage I, 14 in the stage II, 34 in the stage III and 6 in the stage IV were designated under clinical staging. All patients were divided into two groups as GEM group and GEM-125I group. GEM group underwent chemotherapy with GEM only and GEM-125I group was treated under CT guided radioactive seed 125I implantation combined with Gemcitabine. Results: GEM group showed tumors under controlling as PR in 5, SD in 14, PD in 11 cases; the total effective rate was 16% and the total control rate was 63%. The median survival time was 7 months and one years survival rate was 26%. GEM-125I group revealed CR in 5, PR in 11, SD in 8, PD in 6 cases and the total effective rate reached 36% with total control rate as 80%. The median survival time was 12.3 months and one year survival rate was 50%. There was a significant difference (P125I implantation combined with Gemcitabine in treatment for the patients with peripheral non-small cell lung cancer (NSCLC)has fine clinical efficiency with minimal damage and few complications. (authors)

  20. CT-guided 125I seed implantation for locoregional lymph node metastases in patients with recurrent gastric cancer

    International Nuclear Information System (INIS)

    Objective: To evaluate the safety and short term effect of 125I seed implantation for locoregional lymph node metastases in patients with recurrent gastric cancer. Methods: The data of 23 gastric cancer patients with locoregional lymph node metastases treated by CT-guided 125I seed implantation were retrospectively studied. Patient characteristics and survival data were collected and analyzed. The procedure for seed implantation was performed under CT guidance according to preoperative treatment planning. Evaluation of short-term effect was carried out two months after the 125I seed implantation using response evaluation criteria in solid tumors (RECIST). The 1-, 2-and 3-year survival rates were plotted using the life table method.The potential predictors of survival were tested using univariate Cox models. Log-rank method was used to test the difference of survival in subgroups with tumor size >3 cm and <3 cm. Twenty patients underwent fluoropyrimidine-based chemotherapy after 125I seed implantation. Results: None of the 23 patients had serious complications. Two months after 125I seed implantation, the CR, PR and PD rates were 60.9% (14/23), 21.7% (5/23) and 17.4% (4/23), respectively. The median survival time was (22.1±5.1) months,and the 1-, 2-, 3-year survival rates were (87±7)%, (47± 11)% and (13 ±9)%, respectively. The tumor size (longest diameter) was the most significant factor for prognosis (?2=9.752, P=0.002). Patients with tumor <3 cm in diameter had longer survival time than those with tumor >3 cm ((30.0±5.1) vs (17.0±5.0) months; ?2=5.828, P=0.016). Conclusion: CT-guided brachytherapy using 125I seed implantation is a safe and effective method for palliative treatment of locoregional lymph node metastases for recurrent gastric cancer. (authors)

  1. 125I seeds implant combined with internal iliac arterial infusion chemotherapy in the treatment of recurrence pelvic malignant tumors

    International Nuclear Information System (INIS)

    Objective: To explore the clinical value of seeds implantation technique under CT guidance, combined with internal iliac arterial infusion chemotherapy in the treatment of recurrence pelvic tumors. Methods: Eight patients with recurrence pelvic tumors have been treated by 125I seeds implant combined with internal iliac arterial infusion chemotherapy. The chemotherapy scheme was based on the primary tumor type. Under CT guidance, 125I seeds were implanted into the pelvic tumors according to TPS or Halarism's experienced function: mCi = Da x 5 (Da means the average of length, width and height of the lesion). mCi is the total activity of 125I. The number of 125I seeds needed equals to that of total activities divided by the activity of single particle. Results: All the patients received PET-CT chest follow up two months later. CR, PR, NC, PD were abtained in 0, 5, 2, 1 cases respectively. Two patients died within one year, other 6 patients are still alive, the longest survival period was more than 15 months, the 1-year survival rates was 75%. Conclusions: 125I seeds implant combined with internal iliac arterial infusion chemotherapy is an effective method in the treatment of pelvic recurrence tumors. (authors)

  2. Method of dosimetry planning and implantation of /sup 125/I for interstitial irradiation of malignant gliomas

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    Eddy, M.S.; Selker, R.G.; Anderson, L.L.

    1986-01-01

    Utilizing a treatment concept geared to the cell cycle of the glioma, a CT determined tumor volume and boundaries, /sup 125/I dosimetry data and a reference probe template system, it is now feasible to produce a volume implant of an intracranial mass based on prospective planning with accurate postimplant correspondence. The cell cycle oriented treatment plan is felt perhaps to be more beneficial in the treatment of the highly malignant glioblastoma, considering its wide range of cell cycle times, large irregular volumes and large dormant segment, than would be a similar isotope source delivering a high-dose rate, but short-term course irradiation. Seeds are contained within Lexan tubes, thereby allowing accurate assessment of postoperative dosimetry planning, negating seed migration and possible cold spots within a volume implant as would be noted with unrestrained seeds. The implant described in this communication is designed to remain in place for approximately 20 months, a period of time well beyond the life expectancy of any group of failed glioma patients. Although ultimately the system may prove most beneficial in newly diagnosed glioblastomas, the current trial in patients having previously undergone 5-6000 rads of external beam therapy is not considered hazardous to surrounding brain.

  3. Clinical analysis of 125I seed implants in worst-casts of the malignant tumors after radiography and chemotherapy

    International Nuclear Information System (INIS)

    Objective: To investigate the curative effect and side reaction after 125I seed implanted among tissue were treated the malignant neoplasm by radiography and chemotherapy. Methods: Retrospective analysis the cancerous sufferer after the failure of radiography and chemotherapy, percutaneous puncture or intraoperative under gaze forward 125I seed were implanted the bed of the tumour forever. Follow-up blood routine examination, symptom, sign, using USG or CT observe the change of the tumour and the distribution of the particles etc. Results: In 3 cases, treat 2 cases, tumour reduced obviously, symptoms improved obviously, the face of the ulcer cured, the particles did not shift, hemogram did not decline obviously. Conclusion: 125I seed among the tissue implanted forever for the unsuccessful case after radiography and chemotherapy supply a new therapeutic methods. In the neat future curative effect is exactly, toxic reaction is small, which can remedy the deficiency of the treatment for radiography and chemotherapy. (authors)

  4. Nursing care for patients with local recurrent rectal cancer after CT-guided 125I seed implantation therapy

    International Nuclear Information System (INIS)

    Objective: To discuss the nursing care strategy for patients with local recurrent rectal cancer who has been treated with CT-guided 125I seed implantation therapy. Methods: Twenty patients with local recurrent rectal cancer received a series of nursing interventions, including comfort care and pain care. The clinical results were observed and analyzed. Results: The therapy was smoothly accomplished in all patients. The pain was remarkably relived and the anxiety was alleviated. No displacement of implanted 125I seed occurred. Conclusion: For patients with local recurrent rectal cancer occurred after CT-guided 125I seed implantation therapy, careful nursing can effectively relieve the pain and anxiety feeling,and the living quality can also be markedly improved. (authors)

  5. 125I implantation combined with chemotherapy for treatment of local recurrent stage ? non-small cell lung cancer

    International Nuclear Information System (INIS)

    Objective: To investigate the associated effect of 125I implantation plus chemotherapy in local recurrent stage ? NSCLC patients. Methods: From January 2006 to January 2009, 34 patients documented with local recurrent stage ? NSCLC were divided into two groups by random number table. The treatment group was treated with 125I permanent implantation combined with DP regimen (docetaxel 60 mg/m2 + cisplatinum 75 mg/m2), while the control group received only DP chemotherapy. According to the TPS, the treatment group received CT-guided percutaneous implantation of 125I seeds with a particle activity of 2.22 ×107-2.59 × 107 Bq. The prescribed dose was in the range of 90-110 Gy and the postoperatively matched peripheral dose (mPD) and D90 were verified by TPS. The control group received a DP chemotherapy regime for 4 cycles after the procedure. This study was approved by the ethics committee,and all patients signed informed consents. The follow up time was up to disease progression. Kaplan-Meier survival analysis was used to describe the local lesion control (LLC) time and progression free survival (PFS). Log-rank test was used in the comparison of the survival rates between the two groups. Fisher's exact test was used to analyze the differences of CR rate and recent efficiency between two groups. Results: In the treatment group, postoperative mPD was 93.9-130.4 (M 116.7) Gy, and D90 was 103.6-148.2 (M 130.6) Gy. The LLC time was 4.7 to 24.0 months with a median of 11.6 (95% CI: 8.7-14.6) months. In two cases, there was no recurrence during the follow-up time of 24 months.PFS was 4.7 to 24.0 months with a median of 10.5 (95% CI: 7.4-13.6) months. The recent effective rate of the treatment group was 64.7% (11/17).CR, PR, SD and PD were 41.2% (7/17), 23.5% (4/17), 23.5% (4/17) and 11.8% (2/17), respectively. In the control group, the LLC time was 4.5 to 11.4 months with a median of 7.5 (95 % CI: 6.7-8.3) months, and the median of PFS was 6.5 (4.5-10.5) (95% CI: 5.7-8.3) months. The response rate, CR, PR, SD and PD were 41.2% (7/17), 5.9% (1/17), 35.3% (6/17), 35.3 % (6/17) and 23.5% (4/17), respectively. There was no statistical significance of the recent effective rate between the treatment group and control group (P=0.30), but the LLC time (?2=8.40,P<0.01), the median of PFS time (?2=6.27, P<0.05) and CR (P=0.04) of the treatment group were all significantly higher than those of the control group. Conclusion: The implantation of 125I seeds combined with chemotherapy for recurring stage ? NSCLC patients is safe and effective, and its efficacy is superior to the second line chemotherapy alone. (authors)

  6. Characterization of some dosimetric parameters of 125I seeds used for prostate implants using Monte Carlo simulations

    International Nuclear Information System (INIS)

    In the prostate cancer treatment, there is an increasing interest in the permanent radioactive seeds implant technique, where 125I seeds are inserted into the patient's prostate, allowing the delivery of high doses and preserving nearby organs at risk. For the calculation of dose distributions, treatment planning systems (TPS) makes use of the calculation proposed by the protocol TG-43. According to the document, data of dose distribution should be made more precise, either experimentally or by computational simulations, to be used in the TPS. Several authors used Monte Carlo simulations to generate the parameters of brachytherapy sources (seeds) that are recommended by TG-43 protocol, which are used for dose calculations in the TPS. For a single seed, there are variations in the geometry chosen to calculate the dosimetric parameters recommended and in the medium where the dose distributions are calculated (liquid water or solid water) and also in the Monte Carlo code used. The TPS consider the sources as point entities and do not consider the attenuation effects among the seeds. In this work, computational simulations of the geometry of one of the most used seeds in permanent prostate implants, the Amersham model 6711, were performed through the Monte Carlo method using the MCNP5 code. The dosimetric parameters radial dose function g(r) and anisotropy function F(r,?) were simulated and the results show good agreement with other works. This model can be used in the future to study the impact of the approaches and other problems in the implant procedure. (author)

  7. Skills and the Clinical Application of CT Guided Radioactive Seed 125I Implantation in Treating Multiple Lung Metastatic Masses

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    Xuequan HUAN

    2010-03-01

    Full Text Available Background and objective 125I seed implantation treatment of pulmonary metastases, often because of complicated structure of the chest, was considered as restricted areas. The aim of this study is to evaluate the effectiveness of CT guided radioactive 125I seed implantation in treating lung metastatic tumors. Methods Totally 115 metastatic masses were found in 30 patients with CT guiding. 125I seeds were implanted into lung metastatic masses. The approach of implantation was determined according to the location of the lesions (hilar masses, peripheral masses and masses covered by skeletal thorax. The therapeutic effects were evaluated by CT. Results Uniform distribution were achieved by single puncture in 84.3% of patients. The rest patients (15.7% were received replanting. The follow-up period was 6-24 months (mean 14.6. Among 115 lesions in 30 cases, complete response (CR was achieved in 80 nodes, partial response (PR in 20 nodes, No change (NC in 8 nodes and progressive disease (PD in 7 nodes. The total response rate was 86.9%. The one-year local control rate were 93.9% (108/115. No severe perioperative complications occurred. Conclusion CT guided radioactive seed 125I implantation is a safe and effective procedure in treating multiple lung metastatic tumor with minimal invasion.

  8. Radiation protective nursing intervene of 125I seed implantation in non-small cell lung carcinoma guided by CT

    International Nuclear Information System (INIS)

    Objective: To research radiation protective nursing intervene and important notice of 125I seeds minimally invasive implantation in non-small cell lung carcinoma (NSCLC) by CT. Methods: Under the system of therapy planning system (TPS) and posologic validation, 125I seeds were implanted in 89 cases of NSCLC patients. The consistent radiation protective nursing intervene was used in perioperative period management. The operative successful rate, therapeutic effect and complication rate, therapeutic effect and complication rate was observed. Results: The scientific radiation protective nursing intervene can ensure that the radioactive dose distribution of 125I seed implantation brachytherapy is consistent with the principles of effective and minimally invasive. The operative successful rate was 100%. The local control rate and 1 year survival rate respectively was 97.4% and 92.2%. But the early and later incidence rate of radioactive damaging effect was 14.6% and 1.1% respectively. Leakage of radioactive contamination has not occurred. Conclusion: The consistent TPS and posologic validation 125I seeds implantation integrated scientific radiation protective nursing intervene. It is very important to improve the therapeutic effect of NSCLC and reduce the incidence of complications. (authors)

  9. From manual to 3-D computerized treatment planning for 125I stereotactic brain implants

    International Nuclear Information System (INIS)

    Aspects of planning for the treatment of high grade primary or recurrent brain tumors with stereotactically placed catheters afterloaded with high activity 125I seeds are discussed. At our institution, planning has evolved from a simple manual process, which assumed geometric symmetry, through a more advanced manual process, that took advantage of certain mechanical properties of the stereotactic frame used, into a sophisticated, computerized planning approach that includes optimization of the source distribution and 3-D displays. Use of the simple manual method is limited to the rare situations where target volumes are quite regular in shape. The advanced manual method provides some customization for irregularly shaped volumes, but is slow and tedious to implement. The interactive, computerized approach permits identification of target volumes directly on CT slices, reconstructions in arbitrary planes, and optimization of catheter placement, source separation along each catheter, and selection of source strengths from an available inventory. A multi-format display feature which includes a probe's eye view perspective is provided to aid in planning. Integral dose-volume histograms for the target volume point out the advantages in using sophisticated, 3-D, computerized planning systems for these implants

  10. CT-guided percutaneous interstitial implantation of 125I seeds into the pancreas: an experimental study in pigs

    International Nuclear Information System (INIS)

    Objective: To investigate the feasibility and safety of percutaneous interstitial implantation of 125I seeds into the pancreas of pig under CT-guidance. Methods: Twelve healthy pigs were equally divided into 6 groups. 125I seed implantation into the pancreatic tail under CT-guidance was performed in pigs of study groups (group A - E), while ghost seeds that contained no radioactive materials were used in the control group (group F). Imaging examination and laboratory tests, including serum amylase, hepatic and renal functions, were conducted before and 1, 7, 15, 21, 30, 60 days after the procedure. Every two pigs (group A - E) were sacrificed each time at 15, 30, 45, 60, and 75 days after treatment, and specimens of pancreas, duodenum, liver, kidney, etc. were collected and sent for pathologic examination. Results: The 125I seeds were successfully implanted in all pigs. During the follow-up period, no severe complications occurred. Imaging and pathologic studies demonstrated that in study groups necrosis of pancreatic tissue appeared around the implanted 125I seeds in 15 days, the necrosis area increased significantly in 45 and 60 days, and in 75 days the necrosis size remained quite the same as seen in 60 days. No necrosis was found in the control group (group F) 60 days after treatment. No serious complications, such as effusions, hemorrhage or necrosis of the adjacent duodenum, stomach, liver or kidney, occurred 75 days after the treatment. Conclusion: Percutaneous interstitial implantation of 125I seeds into the pig's pancreas under CT-guidance is safe and feasible. (authors)

  11. Moessbauer effect studies following ion implantation of 125I and sup(125m)Te radioactivities in crystalline Ge

    International Nuclear Information System (INIS)

    Moessbauer effect spectra of the sup(125m)Te and 125I sources were taken with a thin single line absorber (ZnTe) using a conventional spectrometer in which the source was moved. sup(125m)Te and 125I sources showed similar spectra, which consisted of two partially resolved peaks, and the positive velocity peak exhibited a somewhat larger intensity. The spectra were fitted to superposition of two Lorentzean line shapes. The interpretation of the present data, guided by previous two Te implantation results is the following: the two peaks in these spectra belong to two chemically inequivalent Te sites characterized by different IS's and negligible QI. (Auth.)

  12. Development of measurement method using TLD for workers occupation personally exposed to 125I seed source in the implant

    International Nuclear Information System (INIS)

    Objective: To explore the method for measuring and calculating both absorbed dose and effective dose received in organ and tissues of occupational workers by using TLDs for the implantation of 125I seed sources. Methods The experiments with 60Co ?-rays were carried out for the stability. A group of TLD chips was exposed to 125I seed sources to establish standard dose curve for air kerma. During the 125I seed implantation, the TLD chips were pasted to 13 locations like thyroid inside and outside the lead aprons worn by occupational workers to measure average absorbed dose and calculate the absorbed doses and effective to organs and tissues. Results: For 3 cases of prostate cancers with implantation of 125I seeds, the worker's organs and tissues received the absorbed dose 0.02 -3.80 ? Gy and effective dose 0.06- 1.81 ?Sv outside lead aprons and the highest absorbed dose 2.35 ? Gy and effective 0.02 ?Sv inside lead aprons, respectively, with more than 65.9% of rays shielded. For 3 cases of brain cancers with implantation of 125I seeds, the workers received the absorbed dose 0.23 - 11.31 ?Gy and effective dose 0.88-4.07 ?Sv outside lead aprons and the highest absorbed dose 2.22 ? Gy and effective dose 0.09 ?Sv inside lead aprons, respectively, with more than 54.5% of rays shielded. For 3 cases of lung cancers with implantation of 125I seeds, the workers received the absorbed dose 0.03 - 14.78 ?Gy and effective dose 0.35 -7.59 ?Sv outside lead aprons and the highest absorbed dose 4.09 ?Gy and effective 0.22 ?Sv inside lead aprons, respectively, with more than 58.4% of rays shielded. For 2 cases of mediastinum cancers with implantation of 125Iseeds, the workers received the absorbed dose 0.06 - 74.91 ?Gy and effective dose 0.83-17.96 ?Sv outside lead aprons and the highest absorbed dose 10.29 ?Gy and effective 0.5 ?Sv inside lead aprons, respectively, with more than 85% of rays shielded. For one case of ovary cancer with implantation of 125I seeds, the worker received the absorbed dose 0.09-14.29 ?Gy and effective dose 2.40-4.50 ?Sv outside lead aprons and the highest absorbed dose 7.77 ?Gy and effective 0.12 ?Sv inside lead aprons, respectively, with more than 34% of rays shielded. For one case of eye cancer with implantation of 125I seeds, the workers received the absorbed dose 2.2-39.84 ?Gy and effective dose 4.48-10.06 ?Sv outside aprons and the highest absorbed dose 5.19 ?Gy and effective 0.16 ?Sv inside aprons, respectively, with more than 54.6 % of rays shielded. Conclusions: The method of using TLDs to measure the doses to the occupational workers in the course of the implantation of 125I seed sources is simple and easy to operate. It would be an effective approach to protecting medical workers in the case of brachytherapy. (authors)

  13. The implantation of esophageal stent with radioactive 125I particles for advanced esophageal carcinomas: observation of therapeutic results

    International Nuclear Information System (INIS)

    Objective: To investigate the therapeutic effect of the implantation of esophageal stent with radioactive 125I particles in treating advanced esophageal carcinomas in aged patients. Methods: During the period from Sep. 2009 to Dec. 2010, implantation of esophageal stent was used to treat 43 aged patients with advanced esophageal cancer. Based on the patient's free will, the patients were divided into study group (n=18) receiving stent with 125I particles and control group (n=25) receiving ordinary stent without 125I particles. No significant difference in the age, the lesion length, the degree of stenosis and the disease stage existed between the study group and the control group. The technical success rate, the remission rate of dysphagia, the occurrence of complications and the mean survival time were calculated and analyzed. The results were compared between the two groups. Results: The technical success rate was 100% in both groups. The short-term remission rate of dysphagia was also 100% in both groups. The mean survival time in the study group and in the control group was 9.8 months and 4.8 months respectively, the difference between the two groups was statistically significant (P0.05). Conclusion: This results of study indicate that for the treatment of advanced esophageal carcinomas the implantation of esophageal stent with radioactive 125I particles can surely and markedly prolong the patient's survival time and relive the symptom of dysphagia. This technique is safe, feasible and effective in clinical practice. The use of the stent with radioactive 125I particles is superior to the use of the traditional stent in treating patients with advanced esophageal cancer. (authors)

  14. {sup 125}I seed implant brachytherapy for the treatment of parotid gland cancers in children and adolescents

    Energy Technology Data Exchange (ETDEWEB)

    Zheng, L.; Zhang, J.; Song, T.; Zhang, J.; Yu, G.; Zhang, Y. [Peking University School and Hospital of Stomatology, Beijing (China). Dept. of Oral and Maxillofacial Surgery

    2013-05-15

    Background and purpose: There is a lack of optimal treatment strategies for managing salivary gland cancers in children and adolescents. This study is aimed at assessing the effect of {sup 125}I seed implantation for the treatment of parotid cancers in children and adolescents. Patients and methods: A total of 12 patients younger than 16 years with parotid gland malignant tumors underwent {sup 125}I seed implant brachytherapy between October 2003 and November 2008. All patients were assessed after treatment and at the local tumor control appointments. Facial nerve function, maxillofacial development, and radioactive side-effects were assessed. Results: The follow-up period ranged from 41-104 months. One patient with T4b died of pulmonary metastasis. The other patients were alive during the follow-up period. There were no serious radiation-related complications. The treatment did not affect facial nerve function and dentofacial growth in any of the children. Conclusion: For parotid gland cancers in children, {sup 125}I seed implant brachytherapy may be an acceptable treatment without serious complications and with satisfactory short-term effects. (orig.)

  15. CT-guided percutaneous interstitial implantation of 125I for recurrent patients of postoperative non-small cell lung carcinoma

    International Nuclear Information System (INIS)

    Objective: To evaluate the efficacy of percutaneous interstitial implantation with 125I seeds for recurrent patients of postoperative non-small cell lung carcinoma (NSCLC) guided by CT. Methods: Thirty-two NLCLC patients were verified by biopsy pathology. Prescribed dose was 90 Gy. The percutaneous interstitial implantation of 125I seeds treatment was guided by CT. The carcinoma were scanned by CT and compared before and 6 months after treatment. Then judge the curative effect according to the curative standard put forward by World Health Organization. All the patients were followed-up for 6 to 72 months, mean 24 months. Results: The mean radioactive dose of therapy group was 153.7 Gy, D90 was 93.5 Gy. Among the 32 follow-up cases, the complete and partial remission rate was 90.6%, and no major complications. One and two year survival rate were 87% and 73%, mean survival was 35 months. Conclusion: Percutaneous interstitial implantation with 125I seeds for recurrent patients of postoperative NSCLC guided by CT is a valid, minimally invasive and efficient method. (authors)

  16. Identification of new collagen formation with 125I-labeled antibody in bovine pericardial tissue valves implanted in calves

    International Nuclear Information System (INIS)

    Failure of bovine pericardial tissue valve used in young patients may be due to a slow rejection process. Polyclonal anticollagen (Type I) antibody (IgG) was made in rabbits and purified by protein A affinity column. Two milligrams of IgG was labeled with 2 mCi of 125I by the Iodogen method. Free iodide was separated by G-10 column. Affinity of 125I-IgG was checked by radioimmunoassay. Two hundred and fifty microcuries of 125I-IgG was injected in calves immediately after tissue valve implantation, and the calves were killed 4 h post-injection. After harvesting the valve, each of the three leaflets was separated into four zones, and radioactivity in each section was mapped with a γ counter. The radioactivity in tissue valve section was compared to that of normal aortic valve. The sections of tissue valve retain five to ten times more 125I-IgG than control aortic valve. Iodine-IgG thus provides a sensitive technique for determination of residual antigenicity in tissue valve. (author)

  17. Identification of new collagen formation with /sup 125/I-labeled antibody in bovine pericardial tissue valves implanted in calves

    Energy Technology Data Exchange (ETDEWEB)

    Dewanjee, M.K.; Singh, S.K.; Wooley, P.H.; Mackey, S.T.; Solis, E.; Kaye, M.P.

    1986-01-01

    Failure of bovine pericardial tissue valve used in young patients may be due to a slow rejection process. Polyclonal anticollagen (Type I) antibody (IgG) was made in rabbits and purified by protein A affinity column. Two milligrams of IgG was labeled with 2 mCi of /sup 125/I by the Iodogen method. Free iodide was separated by G-10 column. Affinity of /sup 125/I-IgG was checked by radioimmunoassay. Two hundred and fifty microcuries of /sup 125/I-IgG was injected in calves immediately after tissue valve implantation, and the calves were killed 4 h post-injection. After harvesting the valve, each of the three leaflets was separated into four zones, and radioactivity in each section was mapped with a ..gamma.. counter. The radioactivity in tissue valve section was compared to that of normal aortic valve. The sections of tissue valve retain five to ten times more /sup 125/I-IgG than control aortic valve. Iodine-IgG thus provides a sensitive technique for determination of residual antigenicity in tissue valve.

  18. CT-guided radioactive 125I-seed implantation for the treatment of pancreatic carcinoma: a clinical observation of 19 cases

    International Nuclear Information System (INIS)

    Objective: To explore the dynamic changes of serum tumor markers after CT-guided radioactive 125I-seed implantation treatment in patients with pancreatic carcinoma and to assess the therapeutic effectiveness of 125I-seed implantation. Methods: CT-guided radioactive 125I-seed implantation was performed in 19 patients with unresectable advanced pancreatic cancer. Treatment planning system was used to reconstruct 3-dimentional images of the tumor, and the quantity and distribution of 125I-seeds to be implanted were thus determined. Under CT guidance 125I-seeds were embedded into pancreatic cancer. Before and after the 125I-seed implantation the levels of serum tumor markers, including CEA, CA19-9 and CA50, were determined by using radioimmunoassay method. The clinical effects were observed and the therapeutic results were statistically analyzed. Results: The pain stared to be relieved 2 to 5 days after implantation. The total effective rate (CR + PR) at one and three months after treatment was 68.42% (13 /19) and 63.16% (12 /19) respectively. One month after 125I-seed implantation, the levels of serum CEA, CA19-9 and CA50 were significantly different to that determined before implantation in all cases (P 125I-seed implantation is a safe and effective interventional treatment for advanced pancreatic cancer with reliable short-term result and remarkable pain-relieving effect. Moreover, this therapy can significantly lower the levels of many serum tumor markers, which play some suggestive roles in evaluating the clinical curativeness. (authors)

  19. Clinical efficacy of CT-guided 125I radioactive seeds implantation for stage ? of non-small cell lung cancer

    International Nuclear Information System (INIS)

    Objective: To evaluate the clinical effects of CT-guided 125I radioactive seed implantation in treatment of stage ? non-small cell lung cancer (NSCLC) and the influential factors of prognosis. Methods: 247 patients of stage ?a/?b NSCLC underwent CT-guided 125I radioactive seed implantation. The clinical effects and the factors affecting prognosis were analyzed by univariate and multivariate analyses. Results: The 1-, 3-, and 5- year overall survival rates were 82.8%, 23.8%, and 11.5 %, respectively. The median survival time was 24.8 months, and the local control rate was 92.2 %, 63.8%, and 25.7%, respectively. The 5- year overall survival rate was 14.7%, and the median survival time was 29.7 months of the stage ?, patients. And the 5- year overall survival rate was 11.2%, and the median survival time was 24.0 months at the stage ?b. Univariate analysis showed that age, course of disease, hemoglobin before treatment, clinical stage, maximum diameter of tumor, prescribed dose (PD), post-operational mean dose,post-operational dose covering 100% volume (D100), remedial model were the main prognostic factors; however, multivariate analysis revealed that hemoglobin ? 120 g/L before treatment, post-operational dose covering 100% volume (D100) and maximum diameter of tumor were the independent risk factors for predicting the survival. Aerothorax was observed in 37 patients with an incidence rate of 14.9%, and hemothorax was observed in 22 patients with an incidence rate of 9%. Conclusions: 125I radioactive seed implantation therapy is effective in the treatment of stage ? NSCLC. Hemoglobin level before treatment, post-operational dose covering 100% volume (D100), and maximum diameter of tumor are the main prognostic factors for the NSCLC patients treated with radiotherapy for NSCLC. (authors)

  20. The clinical analysis of 125I particles implantation by fibrobronchoscope and percutaneous in the treatment of tracheal stenosis of advanced lung cancer

    International Nuclear Information System (INIS)

    Objective: To evaluate the clinical efficacy of 125I particles implantation in the treatment of tracheal stenosis due to advanced lung cancer. Methods: Eighteen cases with end stage lung cancer were collected.125I particles were implanted by inserting the bronchoscope into the pathological bronchial tubes of distal puncture. The number of 125I particles implanted ranged from 4-15. The tumor sizes were compared before and 30 d, 60 d, 180 d after the 125I particles implantation according to the examination of CT, and the clinical symptoms were studied. Results: The symptoms of shortness of breath were relieved after 125I particles implantation. Thirty days follow-up after the therapy showed 15 cases of enlarged bronchial lumen, 13 cases of disappeared obstructive pneumonia symptoms, and no obvious complication occurred during the follow-up. Conclusion: The implantation of 125I radioactive particles has a good effect for the tracheal stenosis in the treatment of advanced lung cancer; the therapy is safe and worth to be spread. (authors)

  1. A nomograph for permanent implants of Palladium-103 seeds

    International Nuclear Information System (INIS)

    103Pd is being substituted for 125I in permanent implants for which it is desired to deliver a higher initial dose rate while maintaining readily achieved radiation protection. The authors have constructed a nomograph to assist in determining both the total seed strength required and the appropriate needle spacing for 103Pd implants. They have calculated the open-quotes matched peripheral doseclose quotes (MPD), that is, the dose for which the isodose contour volume is equal to the target volume, for 64 125I and 13 103Pd actual implants as if 103Pd had been used for all of them, employing a computer lookup table based on single-seed dose distribution measurements in solid water. The calculated data were used to obtain a least-squares fit to a linear relationship between the logarithm of the total seed strength for a given MPD and the logarithm of the average dimension, da (cm). They found that, for a nominal MPD of 11,500 cGy, total seed strength (in mCi) is given by 3.2 da2.56. A 103Pd nomograph has been constructed on the basis of this power function relationship. The nomographic guide for planning 103Pd implants calls for total seed strength to increase significantly faster as a function of target volume average dimension than is the case for 125I. This nomograph will facilitate the application of 103Pd seeds in permanent implants

  2. 125I interstitial implants in the RIF-1 murine flank tumor: an animal model for brachytherapy

    International Nuclear Information System (INIS)

    The development of a model for interstitial brachytherapy that uses high-activity, removable 125I sources in the RIF-1 murine flank tumor is reported. Experimental end points are clonogenic cell and tumor regrowth delay assays. For the clonogenic cell assay, interestitial radiation is delivered at total doses of 500-10,000 rad at dose rates of 0.9-2.7 rad/min to cells in annuli of tissue in the tumor. Dose-survival curves are characterized by an initial shoulder followed by a straight (exponential) portion, with D0 similar to that of the curve obtained by external irradiation of the RIF-1 tumor in a self-contained cesium irradiator at similar dose rates. Tumor regrowth curves have been obtained for minimum tumor doses of 500-5000 rad; marked tumor regression has been observed with minimum tumor doses as low as 2000 rad, but results are not as reproducible as the results obtained with the clonogenic cell assay

  3. The clinical application of 125I seeds implantation together with bronchial arterial infusion chemotherapy for the treatment of advanced lung cancer

    International Nuclear Information System (INIS)

    Objective: To assess the clinical value of 125I seeds implantation combined with the bronchial arterial infusion chemotherapy in treating advanced lung cancer. Methods: 125I seeds implantation combined with the bronchial arterial infusion chemotherapy was performed in 30 patients with advanced lung cancer. About 3 -70 seeds of 125I (6711 type, 0.7 mCi / seed) were delivered in each patient. In all patients bronchial arterial infusion chemotherapy was carried out at the time of 7 days before the implantation and 30 and 60 days after the implantation. The results and complications were observed. The clinical data were retrospectively analyzed. The therapeutic efficacy was evaluated according to RECIST standards. Results: A total of 40 lesions were detected in all 30 patients and 125I seeds were successfully embedded in all lesions. No procedure-related complications occurred. All patients were followed up for 2 -24 months. The two-year survival rate was 86.6% (26 / 30). Therapeutic evaluation made at four months after the treatment showed that CR, PR, NC and PD was seen in 26, 10, 2 and 2 lesions respectively,with a total effective rate of 90%. Conclusion: 125I seeds implantation combined with the bronchial arterial infusion chemotherapy is a safe and effective therapy for advanced lung cancer with excellent clinical results. (authors)

  4. Anti-tumor effects of 125I radioactive particles implantation on transplantated tumor model of human breast cancer cells in nude mice

    International Nuclear Information System (INIS)

    Objective: To study the anti-tumor effects of 125I radioactive particles implantation on transplantated tumor model of human breast cancer cells in nude mice and clarify their anti-tumor mechanisms. Methods 120 nude mice transplantated with human breast cancer cells MCF-7 were randomly divided into 3 groups (n=40): 125I radioactive particles implanted group, non-radioactive particles implanted group and non-particles implanted group. The articles were implanted into mice according to Pairs system principle. The expressions of Fas mRNA and protein and the activaties of caspase-3 and caspase-8 enzyme were detected by RT-PCR and Western blotting. The changes of cell cycle were detected by flow cytometry. Results: Compared with non-radioactive particles implanted group and non-particles implanted group, the size of cancer tissues in 125I radioactive particles implanted group was reduced significantly (P0/G1 phase was significantly increased (P125I radioactive particles into transplantated tumor model of human breast cancer cells can kill tumor cells, inhibit the growth cycle of tumor cells and induce the apoptosis of tumor cells in nude mice. (authors)

  5. Is there a preferred strength for regularly spaced 125I seeds in inverse-planned prostate implants?

    International Nuclear Information System (INIS)

    Purpose: To determine whether a preferred seed strength exists for 125I prostate implants preplanned using a fixed intraneedle seed spacing of 1 cm and an objective needle placement strategy within the planning target volume (PTV), and incorporating explicit dose-volume constraints for the PTV and tissues at risk. Methods and Materials: Prostate, urethra, and rectum contours for 10 patients were obtained from transrectal ultrasound studies. The PTV was defined in accordance with Radiation Therapy Oncology Group (RTOG) 0019 protocol. Inverse planning software was used to optimally arrange seeds of strength 0.3-0.8 U to cover the PTV to DRx = 145 Gy, and limit urethra and rectum doses to 150% and 100% of DRx, respectively. Isodose distributions and dosimetric indices were calculated: V200, V150, V100, V90, D100, D90 for PTV; V150 for urethra; and V100 for rectum. For seeds of strength 0.414 and 0.6 U and three prostate sizes, the sensitivity of V90 and D90 to elementary perturbations of the optimal seed arrangement were examined. Results: For our planning scenario, 125I seeds of strength 0.5-0.6 U provided the best possible PTV coverage while maintaining V200 at ?25%. The source arrangement for 0.6-U seeds was only modestly more sensitive to perturbations than that for 0.414-U seeds. These findings may not be applicable to implants planned manually or that involve needle placement outside the PTV. Conclusion: Given a particular source arrangement, inverse planning aimed at maximizing dosimetric coverage of the prostate while limiting doses to the urethra and rectum can be used to search for a preferred seed strength. For regularly spaced sources within the PTV, higher strength seeds can provide better dose coverage and better urethral protection than lower strength seeds

  6. Study of percutaneous 125I seeds implantation guided by CT in elderly patients of stage I peripheral non-small cell lung cancer

    International Nuclear Information System (INIS)

    Objective: To evaluate the efficacy, feasibility and safety of CT guided percutaneous 125I seeds implantation in elderly patients of stage I peripheral non-small cell lung cancer (NSCLC). Methods: Clinical data of 16 elderly peripheral stage I NSCLC patients (10 squamous carcinoma and 6 adenocarcinoma; 13 stage IA and 3 stage IB) who received radioactive 125I seeds implantation because of refusal or being unsuited to operation or external radiotherapy were retrospectively analyzed. Prescribed dose was 140 - 160 Gy. Under CT guidance, 125I seeds were implanted percutaneously into tumors for interstitial radiotherapy according to treatment plan system. Results: Mean number of 125I seeds each patient received was 21.1. 12 complete response (CR) and 4 partial response (PR) were achieved. Total response rate (CR + PR) was 100%. 100% patients completed 10 to 56 months of follow-up, 15, 13, 8 and 6 patients completed 1-, 2-, 3-and 4-years' follow-up, respectively. The median local progression free time was 14 months. The 1-, 2-, 3-and 4-year overall survival rate were 60%, 54%, 50% and 33%, respectively (median : 14 months). 7 cases died of non-tumor disease and 5 died of metastasis. No severe complications were observed. Conclusions: CT guided 125I seeds implantation is a safe, reliable and effective radical treatment method for elderly stage I peripheral NSCLC patients, who refuse to or are unsuitable to operation or external radiotherapy. (authors)

  7. Clinical efficacy of interstitial implantation of 125I seeds combined with chemotherapy in patients with non-small cell Lung carcinoma

    International Nuclear Information System (INIS)

    To evaluate the clinical efficacy of 125I seed implantation combined with chemotherapy in the treatment of patients with non-small cell lung carcinoma(NSCLC). The patients with NSCLC (n=64) were received interstitially 125I seed implantation by CT-guided, and then were treated with NVB and DDP after three days. In control group (n=70), the patients were only treated with NVB and DDP. The therapeutic efficacy was observed after two,four and six months. The results showed that the effective rates (CR + PR) after two, four and six months of the treatment were 82.8%, 90.6%, 93.7%, respectively. The effective rates in the control group were 4.4%, 48.6%, 52.9%, respectively. The therapeutic effects had significant difference between two groups (P125I seed implantation and chemotherapy in patients with NSCLC to reduce tumor load in a short period and improve the therapeutic efficacy. (authors)

  8. Pharmacokinetics of 3-[125I]iodo-?-methyl-L-tyrosine, a tumor imaging agent, after probenecid loading in mice implanted with colon cancer DLD-1 cells

    International Nuclear Information System (INIS)

    Introduction: In order to improve tumor imaging, changes in the pharmacokinetics of 3-[123I]iodo-?-methyl-L-tyrosine ([123I]IMT), an artificial amino acid that exhibits high tumor accumulation, after probenecid (PBC) loading was studied in mice implanted with colon cancer DLD-1 cells using 125I-labeled IMT ([125I]IMT). Methods: DLD-1-implanted KSN-slc nude male mice received 740 kBq of [125I]IMT via the tail vein at 5 min after 50 mg/kg body weight PBC loading, and autoradiography was performed at 5, 15 and 30 min after injection. Male ddY mice then received 670 kBq of [125I]IMT and 50 mg/kg 2-amino-bicyclo[2,2,1]heptane-2-carboxylic acid (BCH) or p-aminohippurate (PAH) via the tail vein, and kidney autoradiography was performed at 5 min after injection. In vitro inhibition study was then performed based on the accumulation mechanisms of [125I]IMT in DLD-1, using 1 mM L-tyrosine, BCH, ?-(methylamino)-isobutyric acid, N-benzoyl-?-alanine, PBC, PAH, 2,4-dinitrophenol and sodium azide. Both Na+-dependent and Na+-independent uptake were investigated. Results: Higher tumor accumulation in PBC-loaded DLD-1-implanted mice was seen when compared to control mice. PAH and BCH, respectively, reduced renal accumulation in the tubule segment-2 (S2)-like and S1-like regions. We confirmed that [125I]IMT transport is predominantly mediated by L-type amino acid transporter-1 in DLD-1 cells. Conclusions: [125I]IMT uptake is mediated by organic anion and amino acid transporters in the kidney. Organic anion transporter inhibitors may yield better tumor images with good tumor/normal tissue radioactivity ratios if adequate administration plans are developed

  9. Pharmacokinetics of 3-[{sup 125}I]iodo-{alpha}-methyl-L-tyrosine, a tumor imaging agent, after probenecid loading in mice implanted with colon cancer DLD-1 cells

    Energy Technology Data Exchange (ETDEWEB)

    Nakajima, Syuichi [Department of Radiological Sciences, Ibaraki Prefectural University of Health Sciences, 4669-2 Ami, Ami-machi, Inashiki-gun, Ibaraki 300-0394 (Japan); Division of Health Science, Graduate School of Health Sciences, Kanazawa University, 5-11-80 Kodatsuno, Kanazawa, Ishikawa 9200-942 (Japan); Shikano, Naoto [Department of Radiological Sciences, Ibaraki Prefectural University of Health Sciences, 4669-2 Ami, Ami-machi, Inashiki-gun, Ibaraki 300-0394 (Japan)], E-mail: sikano@ipu.ac.jp; Kotani, Takashi; Ogura, Masato [Department of Radiological Sciences, Ibaraki Prefectural University of Health Sciences, 4669-2 Ami, Ami-machi, Inashiki-gun, Ibaraki 300-0394 (Japan); Nishii, Ryuichi [Research Institute, Shiga Medical Center, 5-4-30 Moriyama, Moriyama-City, Shiga 524-8524 (Japan); Yoshimoto, Mitsuyoshi [Division of Health Science, Graduate School of Health Sciences, Kanazawa University, 5-11-80 Kodatsuno, Kanazawa, Ishikawa 9200-942 (Japan); Yamaguchi, Naoto [Center for Medical Sciences, Ibaraki Prefectural University of Health Sciences, 4669-2 Ami, Ami-machi, Inashiki-gun, Ibaraki 300-0394 (Japan); Iwamura, Yukio [Center for Humanities and Sciences, Ibaraki Prefectural University of Health Sciences, 4669-2 Ami, Ami-machi, Inashiki-gun, Ibaraki 300-0394 (Japan); Kubota, Nobuo; Ishikawa, Nobuyoshi [Department of Radiological Sciences, Ibaraki Prefectural University of Health Sciences, 4669-2 Ami, Ami-machi, Inashiki-gun, Ibaraki 300-0394 (Japan); Kawai, Keiichi [Division of Health Science, Graduate School of Health Sciences, Kanazawa University, 5-11-80 Kodatsuno, Kanazawa, Ishikawa 9200-942 (Japan)

    2007-11-15

    Introduction: In order to improve tumor imaging, changes in the pharmacokinetics of 3-[{sup 123}I]iodo-{alpha}-methyl-L-tyrosine ([{sup 123}I]IMT), an artificial amino acid that exhibits high tumor accumulation, after probenecid (PBC) loading was studied in mice implanted with colon cancer DLD-1 cells using {sup 125}I-labeled IMT ([{sup 125}I]IMT). Methods: DLD-1-implanted KSN-slc nude male mice received 740 kBq of [{sup 125}I]IMT via the tail vein at 5 min after 50 mg/kg body weight PBC loading, and autoradiography was performed at 5, 15 and 30 min after injection. Male ddY mice then received 670 kBq of [{sup 125}I]IMT and 50 mg/kg 2-amino-bicyclo[2,2,1]heptane-2-carboxylic acid (BCH) or p-aminohippurate (PAH) via the tail vein, and kidney autoradiography was performed at 5 min after injection. In vitro inhibition study was then performed based on the accumulation mechanisms of [{sup 125}I]IMT in DLD-1, using 1 mM L-tyrosine, BCH, {alpha}-(methylamino)-isobutyric acid, N-benzoyl-{beta}-alanine, PBC, PAH, 2,4-dinitrophenol and sodium azide. Both Na{sup +}-dependent and Na{sup +}-independent uptake were investigated. Results: Higher tumor accumulation in PBC-loaded DLD-1-implanted mice was seen when compared to control mice. PAH and BCH, respectively, reduced renal accumulation in the tubule segment-2 (S2)-like and S1-like regions. We confirmed that [{sup 125}I]IMT transport is predominantly mediated by L-type amino acid transporter-1 in DLD-1 cells. Conclusions: [{sup 125}I]IMT uptake is mediated by organic anion and amino acid transporters in the kidney. Organic anion transporter inhibitors may yield better tumor images with good tumor/normal tissue radioactivity ratios if adequate administration plans are developed.

  10. Preliminary observations on the results of combined /sup 125/I seed implantation and external irradiation for carcinoma of the prostate

    Energy Technology Data Exchange (ETDEWEB)

    Ross, G. Jr.; Borkon, W.D.; Landry, L.J.; Edwards, F.M.; Weinstein, S.H.; Abadir, R.

    1982-04-01

    Fifty-seven patients with localized carcinoma of the prostate were treated with pelvic lymphadenectomy and a reduced /sup 125/I implant dosage, supplemented by a moderate dose of external beam radiotherapy to the whole pelvis delivered 4 to 6 weeks later. The incidence of pelvic nodal metastases was 28 per cent and the operative morbidity was 15 per cent. Late radiation sequelae developed in 18 patients, including 15 patients with radiation proctitis (29 per cent), among whom 2 (4.6 per cent) suffered rectal ulceration and required diverting colostomy. Followup has been 2 years or longer (median 33 months) in 26 patients, of whom 22 (85 per cent) are free of disease. Three patients are living with osseous metastases or local disease and there has been 1 death of prostatic carcinoma, for an absolute 2-year survival rate of 95 per cent. Of the 7 patients with poorly differentiated tumor and of the 8 patients with positive pelvic lymph nodes 5 and 6, respectively, remain free of disease after a minimum 2-year followup. Potency has been lost in 20 per cent and reduced significantly in 30 per cent of the patients followed 18 months or longer. Prostatic biopsies on 28 asymptomatic patients 12 to 30 months after completion of therapy showed no tumor in 21 (75 per cent).

  11. MSCT-guided percutaneous cryoablation combined with 125I-seed implantation for the treatment of lung cancer: an observation of short-term efficacy

    International Nuclear Information System (INIS)

    Objective: To evaluate the short-term efficacy of MSCT-guided percutaneous argon-helium cryoablation combined with 125I-seed implantation in treating lung cancer, and to discuss the clinical feasibility and safety of this technique. Methods: Under the guidance of MSCT 3D-reconstruction imaging,percutaneous argon-helium cryoablation was performed in 51 patients with advanced lung cancer, which was followed by 125I-seed implantation with the help of treatment plan system (TPS). The 125I seeds were implanted into the edge and the un-frozen area of the tumor according to the therapeutic dosage and distribution calculated by TPS. After the procedure MSCT 3D-reconstruction imaging was carried out to check the location of the implanted 125I seeds. Both plain and contrast-enhanced CT scans of the chest were conducted 1, 2, 3 and 6 months after the treatment. The therapeutic results were analyzed and evaluated. Results: One, 2, 3 and 6 months after the treatment favorable improvement was seen in 9.8%, 19.6%, 56.9% and 46.0% of patients respectively, with the total effective rate of 31.4%, 62.8%, 98.0% and 92.0% respectively. Conclusion: For the treatment of lung cancer MSCT-guided percutaneous puncture argon-helium cryoablation ablation combined with 125I-seed implantation is a safe and minimally-invasive technique with fewer complications and reliable short-term effect. Therefore, it is of value to popularize this therapy in clinical practice. (authors)

  12. Intra-operative dosimetry of trans-rectal ultrasound guided 125I prostate implants using C-arm fluoroscopic images

    Directory of Open Access Journals (Sweden)

    Ravindran Paul

    2006-01-01

    Full Text Available Permanent implantation of radioactive seeds is a viable and effective therapeutic option widely used today for early-stage prostate cancer. The implant technique has improved considerably during the recent years due to the use of image guidance; however, real-time dose distributions would allow potential cold spots to be assessed and additional seeds added. In this study, we investigate the use of a conventional C-arm fluoroscopy unit for image acquisition and evaluation of dose distribution immediately after the implant. The phantom study indicates that it is possible to obtain seed positions within ±2 mm. A pilot study carried out with three patients indicated that it is possible to obtain seed positions and calculate the dose distribution with C-arm fluoroscopy and about 95% of the seeds were reconstructed within ±2 mm. The results could be further improved with better digital imaging.

  13. Linear 125I seed strand implantation combined with portal vein stenting and TACE for the treatment of hepatocellular carcinoma with portal vein tumor thrombus

    International Nuclear Information System (INIS)

    Objective: To evaluate the therapeutic efficacy of linear 125I seed strand implantation combined with portal vein stenting and transcatheter hepatic arterial chemoembolization (TACE) in treating hepatocellular carcinoma (HCC) with portal vein tumor thrombus. Methods: Seventeen HCC patients with tumor thrombus in the main branch of the portal vein received a combination therapy of linear 125I seed strand implantation with TACE. A total of 17 - 23 seeds of 125I (model 6711, 0.7 mCi) with a dosage of (73.51 ? 76.22) Gy on the first half-decay period was delivered to each patient. The postoperative complications, tumor response, stent patency rate and the successful rate of the procedure were all recorded, and the Kaplan-Meier method was used for analyzing the survival rate. Results: Stents and 125I seed strands were successfully placed in the portal veins in all patients. No serious complications occurred. The 60-, 180-and 360-day cumulative stent patency rates were 94%, 94% and 94% respectively, and the overall survival (OS) rates were 87%, 65% and 53% respectively. During a follow-up period of (2 - 13) months, twelve patients remained alive and five patients died of hepatic dysfunction (n = 4) or metastasis (n = 1). Conclusion: For the treatment of hepatocellular carcinoma with portal vein tumor thrombus, a combination of linear 125I seed strand implantation with portal vein stenting and TACE can increase the stent patency rate, elongate the survival span, although its long-term efficacy needs to be further studied. (authors)

  14. 125I implants as an adjuvant to surgery and external beam radiotherapy in the management of locally advanced head and neck cancer

    International Nuclear Information System (INIS)

    125I seeds either individually placed or inserted into absorbable Vicryl suture carriers were utilized in conjunction with surgery and external beam radiotherapy in an attempt to increase local control rates in patients with advanced oropharyngeal and laryngopharyngeal cancers (T3-T4, N2-N3), massive cervical lymphadenopathy (N3) and an unknown primary site and locally recurrent head and neck cancers. Forty-eight patients were treated with 55 implants. The carotid artery was implanted in 15 patients, while seven patients had seeds inserted into the base of the skull region, and another three patients had implants near cranial nerves. Eighteen of the 48 patients were treated for cure. The actuarial survival at five years in this subgroup was 50%. The overall local control in the head and neck area was 58%. In this group no patients to date have had a local failure in the implanted volume. Seventeen patients with comparable stage of disease treated prior to 1974 with curative intent without 125I implants were analyzed retrospectively for comparison with the implanted patients. The actuarial survival of these patients was 18% and the overall head and neck control was 21%. These differences are statistically significant at a P value of 0.01 and 0.007, respectively. Seventeen patients received implants for local recurrence. The local control in the head and neck area was 50%; however, the 2.5 year actuarial survival was only 17%. The complication rate was 11% (six of 55 implants). The improved survival, the high local control, and the minimal complication rates in this series makes the intraoperative implantation of 125I seeds and effective adjunctive treatment to surgery and external beam irradiation

  15. A digital model individual template and CT-guided 125I seed implants for malignant tumors of the head and neck

    International Nuclear Information System (INIS)

    The purpose of this study was to enhance the accuracy of radioactive seed implants in the head and neck, a digital model individual template, containing information simultaneously on needle pathway and facial features, was designed to guide implantation with CT imaging. Thirty-one patients with recurrent and local advanced malignant tumors of head and neck after prior surgery and radiotherapy were involved in this study. Before 125I implants, patients received CT scans based on 0.75 mm thickness. And the brachytherapy treatment planning system (BTPS) software was used to make the implantation plan based on the CT images. Mimics software and Geomagic software were used to read the data containing CT images and implantation plan, and to design the individual template. Then the individual template containing the information of needle pathway and face features simultaneously was made through rapid prototyping (RP) technique. All patients received 125I seeds interstitial implantation under the guide of the individual template and CT. The individual templates were positioned easily and accurately, and were stable. After implants, treatment quality evaluation was made by CT and TPS. The seeds and dosages distribution (D90, V100, V150) were well meet the treatment requirement. Clinical practice confirms that this approach can facilitate easier and more accurate implantation. (author)

  16. Early therapy monitoring of 125I seed interstitial implant in a pancreatic cancer xenograft by 18F-FDG Micro-PET/CT

    International Nuclear Information System (INIS)

    Objective: To investigate the application value of early evaluation and monitoring of 125I interstitial implantation in a pancreatic cancer xenograft. Methods: Xenograft models were created by subcutaneous injection of Sw 1990 human pancreatic cancer cell suspensions into the right hind limbs of the immunodeficient BABL/c nude mice. The tumors size were about 8-10 mm after two weeks. The mice were randomly divided into 3 groups,including control group (n=4), empty seed implantation group (n=4) and 125I implantation group (n=4). Before treatment and one week after treatment, 18F-FDG Micro-PET/CT scan was performed and then maximum standardized uptake values (SUVmax), mean standardized uptake values (SUVmean), tumor size and necrosis rate were measured. HE staining and TK1 immunohistochemistry examination were carried out in the paraffin-embedded sample. Results: Before treatment the SUVmax and SUVmean values of three groups did not reach statistical significance. One week after treatment the SUVmax and SUVmean values of three groups were 3.53±1.20 and 0.57±0.26 vs. 3.83±2.13 and 0.59 ±0.24 vs. 0.29±0.23 and 0.016±0.001, respectively, with a significant difference (F=7.62, P=0.01; F=10.34, P=0.005). The SUVmax and SUVmean values of 125I implant group were significantly lower than empty seed implant group and control group and were significantly lower than before treatment. Before treatment, tumor necrosis rate of three groups were not significantly different. Immunohistochemical staining found the TK1 positive staining index of three groups were respectively (64.25±1.71)%, (62.25±2.22)% and (38.25±1.71)% with statistically significant difference (F=233.67, P<0.001). The TK1 positive staining index of 125I implant group was significantly lower than empty seed implant group and control group. The SUVmax values had some positive correlation with TK1 positive staining index (r=0.85, P=0.001). Conclusions: 18F-FDG Micro-PET/CT may be useful as a noninvasive imaging modality to assess early response to 125I seed brachytherapy in a pancreatic cancer xenograft. (authors)

  17. American brachytherapy society recommends no change for prostate permanent implant dose prescriptions using iodine-125 or palladium-103

    International Nuclear Information System (INIS)

    Purpose - In 2004, the American Association of Physicists in Medicine (AAPM) issued a report outlining recommended 125I and 103Pd datasets for consistency in calculating brachytherapy dose distributions. In 2005, to aid evaluating the clinical impact of implementing these datasets, the AAPM assessed the historical dependence of how prescribed doses differed from administered doses for 125I and 103Pd for permanent implantation of the prostate. Consequently, the American Brachytherapy Society (ABS) considered the nature of these changes towards issuing recommended dose prescriptions for 125I and 103Pd interstitial brachytherapy implants for mono-therapy and standard boosts. Methods and materials - An investigation was performed of the 2005 AAPM analysis to determine changes in administered dose while affixing prescribed dose using 2004 AAPM 125I and 103Pd brachytherapy dosimetry datasets for prostate implants. For 125I and 103Pd, administered dose would change by +1.4% and +4.2%, respectively. The biological and societal impact of changing prescribed dose was considered. Results - Based on the need for clinical constancy and in recognition of overall uncertainties, the ABS recommends immediate implementation of the 2004 AAPM consensus brachytherapy dosimetry datasets and no changes to 125I and 103Pd dose prescriptions at this time. Conclusions - Radiation oncologists should continue to prescribe mono-therapy doses of 145 Gy and 125 Gy for 125I and 105Pd, respectively, and standard boost doses of 100-110 Gy and 90-100 Gy for 125I and 103Pd, respectively. (authors)

  18. Dynamic observation on changes of serum tumor markers levels after implantation of 125I radioactive seeds as treatment for several malignancies

    International Nuclear Information System (INIS)

    Objective: To study the dynamic changes of serum levels of several tumor markers after implantation of 125I seeds as treatment for breast, prostate and lung malignancies. Methods: Serum CA15-3 (in 48 cases of breast cancer), PSA (in 59 cases of prostate cancer) and CYFRA21-1 (in 59 cases of lung cancer) levels were measured with RIA both before and after implantation of 125I seeds as treatment. Furthermore, dynamic observation on the serum markers levels was carried out every 3 months in ten patients in each category. Results: After treatment, levels of these markers dropped significantly. Dynamic observation revealed that in the 10 cases of breast cancer, the levels of CA15-3 dropped continually. However, in the 10 cases of prostatic cancer, the disease got worse and the PSA levels kept increasing. In the lung cancer group, the CYFRA21-1 levels rose markedly and all patients expired before 9 months. Conclusion: Dynamic observation on changes of serum tumor markers (CA15-3, PSA, CYFRA21-1) levels after 125I seed implantation treatment was of definite prognostic value. (authors)

  19. Influence of source batch Sk dispersion on dosimetry for prostate cancer treatment with permanent implants

    DEFF Research Database (Denmark)

    Perez-Calatayud, J; Casares-Magaz, O

    2015-01-01

    PURPOSE: In clinical practice, specific air kerma strength (SK) value is used in treatment planning system (TPS) permanent brachytherapy implant calculations with (125)I and (103)Pd sources; in fact, commercial TPS provide only one SK input value for all implanted sources and the certified shipment average is typically used. However, the value for SK is dispersed: this dispersion is not only due to the manufacturing process and variation between different source batches but also due to the class...

  20. The evaluation of CT-guided interstitial 125I seeds implantation in combined chemotherapy for non-small cell lung cancer

    International Nuclear Information System (INIS)

    Objective: To discuss the clinical value of CT-guided percutaneous embedding of 125I seeds in combined chemotherapy with TP regime for non-small cell lung cancer(NSCLC). Methods: Thirty two patients with NSCLC received CT-guided percutancous embedding of 125I particles, TP chemotherapy plan (paclitaxcl 135 mg/m2/d1, cisplatin 75 mg/m2/d2-4) for four cycles after operation. The follow-up CT for observing therapeutic effects at 1, 3, 6, 12 month after 125I seeds implantation was undertaken. Results: All cases were controlled effectively after one month revealed by CT follow up. The efficiency of tumor curing at 3, 6, 12 month were 87.5%, 90.63%, 92.31% respectively. None of the patients showed radiation injury and particle migration, and all of them had only slight side effects. Conclusion: CT-guided percutaneous embedding of 125I seeds in combination with chemotherapy for non-small cell lung cancer is an effective and safe method, possessing valuable utilization clinically. (authors)

  1. CT-guided 125I seeds implantation combined with NP chemotherapy for the treatment of intractable central airway stenosis caused by NSCLC

    International Nuclear Information System (INIS)

    Objective: To explore the clinical value of radioactive 125I seeds implantation combined with NP in treating intractable central airway stenosis caused by non-small cell cancer (NSCLC). Methods: A prospective cohort study of 80 patients, who were admitted to Beichen hospital (Tianjin, China) during the period from January 2004 to March 2010, were enrolled in this study. The patients were randomly divided into study group (n=42) and control group (n=38). Percutaneous CT-guided intratumoral implantation of 125I seeds was carried out in the patients of the study group. Treatment plan system (TPS) was used to design the distribution and the number of 125I seeds with PD=80-100 CY, and the source intensity was 0.8 mCi. Three days after operation the NP chemotherapy started and it was performed for 2 cycles. Only two cycles of NP chemotherapy was used for the patients in the control group. After the treatment, the cross area of the airway at its narrowest level was measured and the dyspnea index was evaluated. Results: All the patients were followed up for two months. The preoperative and postoperative stenosis rate of the airway in study group was 47.82%±17.55% and 15.76%±4.65%, respectively. The trachea was unobstructed and the dyspnea was markedly improved. The postoperative cross area of the airway at its narrowest level was significantly bigger than the preoperative one (P0.05). Conclusion: Radioactive 125I seeds implantation combined with NP chemotherapy is a safe and effective treatment for NSCLC. (authors)

  2. Preparation and deployment of indigenous 125I- seeds for the treatment of prostate cancer: dawn of prostate brachytherapy in India

    International Nuclear Information System (INIS)

    'Permanent seed implantation' using 125I- seeds represents an effective treatment modality for prostate cancer. An innovative strategy to prepare and deploy 125I- seeds for treatment of prostate cancer has been evolved. Seeds prepared by chemisorptions of 125I on palladium coated silver wires were characterized and encased in titanium tubes by ND:YAG laser. Several batches of critically evaluated seeds exhibiting release of 125I were supplied to P.D. Hinduja Hospital, Mumbai for treatment of prostate cancer patients. Successful deployment of indigenous seeds in prostate brachytherapy has opened a new window for making prostate brachytherapy affordable to needy cancer patients. (author)

  3. Application and progress of image-guided 125I seed interstitial implantation for the treatment of tumor

    International Nuclear Information System (INIS)

    Although radioactive seed interstitial implantation had been used for a long time, the relationship between the physical, biological characteristics, the clinical dose and curative effect, complications had been deeply discussed for decade. Treat the tumor by seed interstitial implantation technology, implanting the radioactive seeds into malignant tumor tissues well-distributed and regularly according to the radiotherapy plans,then the tumor receive higher doses of radiation, while the normal tissue get less or no injure. This seed implanted technology is used for treatment tumors that hard to surgical resection, could not reached complete excision and surgery residual, and implant seeds in tumor edge avoid recurrence and metastasis. Radioactive seed implantation technology for cancer developed rapidly in 10 years,more than 600 hospitals carried out the technology in China recently, and the technology indication will expand to the solid tumors origin from organs such as liver, lung, esophagus, pancreas, rectum, prostate gland, thyroid, head, facial, nasopharynx and so on. (authors)

  4. Permanent Planar Iodine-125 Implants: The Dosimetric Effect of Geometric Parameters for Idealized Source Configurations

    International Nuclear Information System (INIS)

    Purpose: To provide dosimetric information about permanent planar 125I implants in a manner that is useful to the brachytherapist in the operative setting. Methods and Materials: Reference planar permanent implants were simulated for a variety of areas with sources placed uniformly on a 1-cm grid. Implants having variable source spacing and curvature were simulated and compared with the reference implants. Dosimetric measures were calculated at 0.5 and 1.0 cm from the implant plane. Results: A method for calculating dosimetric statistics for permanent implants ranging from 5 x 5 cm to 13 x 13 cm is presented. A formula to predict the reference source strength needed to achieve a desired dosimetric quantity is also presented. The effect of adjusting strand spacing to compensate for source activity is presented and is shown to be an effective means to adjust implants to use source strengths other than the reference strength. The effect of implant curvature compared with flat implants on dosimetric statistics is presented as a function of radius of curvature. Conclusions: The results presented in this work may be used to provide information about dose delivered from planar permanent implants

  5. A clinical method for real-time dosimetric guidance of transperineal 125i prostate implants using interventional magnetic resonance imaging

    International Nuclear Information System (INIS)

    Purpose: The clinical utility of an interventional magnetic resonance (IMR)-guided implant technique with real-time dosimetric feedback is presented. Methods and Materials: The work was carried out at a IMR unit at Brigham and Women's Hospital. Planning and dosimetric feedback were provided by a software system that provides an interface to the IMR images, anatomy demarcation, template registration, dose calculation engine for planning, and evaluating the implant. Planning during the procedure permits the incorporation of actual needle trajectories in the dose calculations. Results: Fifteen patients were planned in the treatment position. During source placement, actual needle locations were incorporated into the dose calculations. After accounting for the observed needle trajectories of the planned needles, 14 of 15 patients (93%) required additional sources to achieve the desired coverage of the target volume. Conclusion: A brachytherapy implant procedure which provides clinically significant advances has been implemented. Specifically, the planning system allows dosimetric validation of the needle placement. This procedure is effective in delivering brachytherapy to the target volume and assuring that the implant is delivered in accordance with the preplan. The dosimetric feedback could be incorporated in ultrasound-guided implants

  6. Combination chemotherapy of gemcitabine and cisplatin by double way plus implantation of radioactive seed 125I in treating stage ? non-small cell lung cancer

    International Nuclear Information System (INIS)

    Objective: To assess the therapeutic effect of combination chemotherapy of gemcitabine and cisplatin by double way plus implantation of radioactive seed 125I implantation in treating stage ? non-small cell lung cancer. Methods: Sixty cases with stage ? non-small cell lung cancer were randomly divided into two groups with random number table. In group A (in interventional treatment group, n=30), the gemcitabine 1000 mg/m2 and one third of the cisplatin 100 mg/m2 was given using Seldinger technique for transcatheter bronchial arterial infusion chemotherapy on day 1. Two-thirds of the cisplatin 100 mg/m2 was infused in veins on day 2 and 3. The gemcitabine 1000 mg/m2 was infused in veins on day 8, 21 days for a period. In group B (interventional - 125I groups), the method of combination chemotherapy of gemcitabine and cisplatin was the same as in Group A. After ten days of arterial perfusion, 125I seeds were implanted, 21 days for a period. All patients received at least 2 cycles. The imaging evaluation of patients after treatment standards included complete remission (CR), partial remission (PR), stable (SD), progressive disease (PD), effective rate (CR + PR)/30 and clinical benefit rate (CR + PR + SD)/30. Non-parametric rank sum test was used to compare short-term effect of the two groups treatment of two cycles. ?2 test was used to compare year survival, Kaplan-Meier method was used to calculate median survival, log-rank test method was used to difference between the groups. Results: In group A, there were 17 PR, 9SD and 4 PD. The overall response rate was 56.7% (17/30) and clinical beneficial rate was 86.7% (26/ 30). In Group B, there were 2 CR, 21 PR, 7 SD. The overall response rate was 76.7% (23/30) and clinical beneficial rate was 100% (30/30). There was significant difference between the two groups (P= 0.036). In group A, the 1 year survival rate was 46.7% (14/30) and the 2 year survival rate was 36.7% (11/30), median survival time (MST) was 10 months. In group B, the 1 year survival rate was 76.7% (23/30) and the 2 year survival rate was 63.3% (19/30), median survival time (MST) was 27 months. There was a significant difference between two group in 1 year survival rate (P=0.017), 2 year survival rate (P=0.039) and median survival time (P=0.006). Conclusion: The treatment effects of ? stage non-small cell lung cancer by gemcitabine and cisplatin combination chemotherapy with double way plus radioactive seed 125I implantation was better than gemcitabine and cisplatin combination chemotherapy with double way. (authors)

  7. Long-term results of ultrasonically guided implantation of 125-I seeds combined with external irradiation in localized prostatic cancer

    DEFF Research Database (Denmark)

    Iversen, P; Rasmussen, F; Holm, H H

    1991-01-01

    Transperineal 125-iodine seed implantation guided by transrectal ultrasonography and subsequent external beam irradiation was employed in the treatment of 32 patients with localized prostatic carcinoma (16 poorly differentiated). Follow-up is currently 35-98 months with a median of 65 months. Dis...

  8. Clinical application of permanent implantation of iodine 125 seeds for osseous metastases

    International Nuclear Information System (INIS)

    Objective: To evaluate the clinical efficacy of permanent implantation of iodine 125 seeds in the treatment of osseous metastases. Methods: Radioactive iodine 125 seeds were implanted permanently in 32 lesions of 25 patients with osseous metastases of different origins. The ostalgia-relieving degree and the imaging alterations of the osseous metastasis lesions were observed. Results: The effective pain-relieving rate was 92% caused by permanent implantation of iodine 125 seeds. Of al 1 the patients, 15 patients achieved complete response, 8 patients obtained partial response (PR), and 2 patients had no change. The pain grade was decreased significantly after the treatment (P125I seeds has a definite effect on tumor metastasis and caused minimal damage and few complications. It is worthy of popularization in clinic. (authors)

  9. Influence of source batch Sk dispersion on dosimetry for prostate cancer treatment with permanent implants

    DEFF Research Database (Denmark)

    Perez-Calatayud, J; Casares-Magaz, O

    2015-01-01

    PURPOSE: In clinical practice, specific air kerma strength (SK) value is used in treatment planning system (TPS) permanent brachytherapy implant calculations with (125)I and (103)Pd sources; in fact, commercial TPS provide only one SK input value for all implanted sources and the certified shipment...... average is typically used. However, the value for SK is dispersed: this dispersion is not only due to the manufacturing process and variation between different source batches but also due to the classification of sources into different classes according to their SK values. The purpose of this work is to...

  10. Disease-related effects of perioperative blood transfusions associated with 125I seed implantation for prostate carcinoma

    International Nuclear Information System (INIS)

    In some retrospective studies perioperative transfusions during oncologic surgery have been shown to decrease the time interval between surgery and local and/or distant recurrence of cancer. This study examines the disease-related effect, if any, of perioperative blood transfusions among 108 patients with localized carcinoma of the prostate treated by radioactive iodine-125 seed implantation of the prostate and lymphadenectomy. When all subjects were analyzed, there was no statistical difference of local and distant failure between the transfused and nontransfused groups. Patients with well-differentiated tumors had statistically fewer local recurrences (0% vs 22%, p = 0.036) if they were transfused perioperatively. However, the difference in distant metastases (0% vs 11%) was not statistically significant (p = 0.21). In contrast, patients with moderately and poorly differentiated disease receiving transfusions had more local recurrences and metastases, though this was not statistically significant. Our data suggest that there is no obvious evidence that perioperative blood transfusions have an adverse effect on local recurrence or distant metastases for iodine-125 seed implantation of carcinoma of the prostate

  11. Radiation protection after interstitial permanent prostate brachytherapy implants

    Energy Technology Data Exchange (ETDEWEB)

    Pirraco, R.; Pereira, A.; Cavaco, A. [Instituto Portugues de Oncologia Francisco Gentil - Centro R egional de Oncologia do Porto, SA, Porto (Portugal)

    2006-07-01

    Full text of publication follows: In this study we measure patients radiation exposure dose after interstitial {sup 125}I permanent prostate Brachytherapy implants, and correlate it with dose limits for public, total activity implanted, patient preoperative weight(1), distance between prostate walls and anterior skin surface. Methods and Material: We analyse 20 patients who were implanted with {sup 125}I seeds. The instrument used to measure radiation is a calibrated Berthold Umo LB 123 aco-plated to a LB 1236-H10 detector. Three measurements were taken: at the perineal and anterior pelvic zones on contact with the skin and at 1 m from the patient. The maximum value was taken for all measurements. The dose at a distance of one meter is obtained at anterior pelvic zone, perpendicular to the skin, according to the recommendations of A.A.P.M.(1). The distance between prostate walls was determined using post -operative CT images. Results: The doses at the perineal zone have determined an average of 186 {mu}Sv/h (range: 110 340 {mu}Sv/h) and at surface pelvic zone of 41 {mu}Sv/h (range: 15 103 {mu}Sv/h). The dose at a distance of 1 meter has an average value of 0.4 {mu}Sv/h (range: 0.2 1.0 {mu}Sv/h). The average total activity implanted was 25 mCi (range: 17 38 mCi). The distance between prostate walls and skin pelvic surface of the patients has an average value of 8.9 cm (range: 6.6 -11.5 cm). At a distance of 1 meter from the pelvic zone the dose measured is very low and below dose limits imposed by the European Directive EURATOM 2 and the Portuguese law. For general public to reach annual dose limit (EURATOM - 1 mSv/year) when contacting the pelvic zone, we extrapolate that 4 days (range: 1.6 11.1 days) would be needed, assuming a daily contact period of 6 hours. Conclusion: We established a correlation between the distance of prostate walls to the skin perineal surface and the total dose, but we find no correlation between measured doses, total activity implanted and patient weight. Our results show that recommendations to the patients must be very careful, stating that all contact must be as short as possible, at least in the first {sup 125}I half life period. References: (1) Yan Yu et all., 'Permanent prostate seed implant brachytherapy: report of the A.A.P.M. - TG 64', Med. Phys, 26 (10), pp. 2054-2076, 1999. (2) S. Smathers, et all., 'Radiation safety parameters following prostate brachytherapy', Int. J. Rad. Onc. Biol. Phys. Vol 45, no 2, pp. 397 -399, 1999. (3) Council Directive 97/43/EURATOM of 30 of June. (authors)

  12. Monte Carlo calculated doses to treatment volumes and organs at risk for permanent implant lung brachytherapy

    Science.gov (United States)

    Sutherland, J. G. H.; Furutani, K. M.; Thomson, R. M.

    2013-10-01

    Iodine-125 (125I) and Caesium-131 (131Cs) brachytherapy have been used with sublobar resection to treat stage I non-small cell lung cancer and other radionuclides, 169Yb and 103Pd, are considered for these treatments. This work investigates the dosimetry of permanent implant lung brachytherapy for a range of source energies and various implant sites in the lung. Monte Carlo calculated doses are calculated in a patient CT-derived computational phantom using the EGsnrc user-code BrachyDose. Calculations are performed for 103Pd, 125I, 131Cs seeds and 50 and 100 keV point sources for 17 implant positions. Doses to treatment volumes, ipsilateral lung, aorta, and heart are determined and compared to those determined using the TG-43 approach. Considerable variation with source energy and differences between model-based and TG-43 doses are found for both treatment volumes and organs. Doses to the heart and aorta generally increase with increasing source energy. TG-43 underestimates the dose to the heart and aorta for all implants except those nearest to these organs where the dose is overestimated. Results suggest that model-based dose calculations are crucial for selecting prescription doses, comparing clinical endpoints, and studying radiobiological effects for permanent implant lung brachytherapy.

  13. Methodology of quality control for brachytherapy {sup 125}I seeds

    Energy Technology Data Exchange (ETDEWEB)

    Moura, Eduardo S.; Zeituni, Carlos A.; Manzoli, Jose E.; Rostelato, Maria Elisa C.M. [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)]. E-mail: esmoura@ipen.br

    2007-07-01

    This paper presents the methodology of quality control of {sup 125}I seeds used for brachytherapy. The {sup 125}I seeds are millimeter titanium capsules widely used in permanent implants of prostate cancer, allowing a high dose within the tumour and a low dose on the surrounding tissues, with very low harm to the other tissues. Besides, with this procedure, the patients have a low impotence rate and a small incidence of urinary incontinence. To meet the medical standards, an efficient quality control is necessary, showing values with the minimum uncertainness possible, concerning the seeds dimensions and their respective activities. The medical needles are used to insert the seeds inside the prostate. The needles used in brachytherapy have an internal diameter of 1.0 mm, so it is necessary {sup 125}I seeds with an external maximum diameter of 0.85 mm. For the seeds and the spacer positioning on the planning sheet, the seeds must have a length between 4.5 and 5.0 mm. The activities must not vary more than 5% in each batch of {sup 125}I seeds. For this methodology, we used two ionization chamber detectors and one caliper. In this paper, the methodology using one control batch with 75 seeds manufactured by GE Health care Ltd is presented. (author)

  14. Preparation and deployment of indigenous 125I-seeds for the treatment of prostate cancer. Dawn of prostate brachytherapy in India

    International Nuclear Information System (INIS)

    'Permanent seed implantation' using 125I- seeds has emerged as an effective treatment modality for management of prostate cancer. An indigenous technology for the production of 125I brachytherapy sources ('BARC 125I Ocu-Prosta seed') has been developed. In this current work, we describe an overview of our experience on large scale production of 125I brachytherapy sources, their quality assessment, in vivo bio-evaluation and initial experience on their journey from bench to bed-side for the treatment of prostate cancer. (author)

  15. Permanent transvenous pacemaker implantation in forty dogs

    International Nuclear Information System (INIS)

    Permanent transvenous cardiac pacemakers were implanted in 40 dogs. Electrocardiographic diagnoses included persistent atrial standstill (3 dogs), sick sinus syndrome (8 dogs), and high-grade second-degree or third-degree atrioventricular (AV) block (29 dogs). Thirteen dogs were alive and well 4 to 42 months after pacemaker implantation (mean, 16.9 months). The mean and median survival times of the 26 dogs that died or were euthanatized during the study were 17.9 months and 13 months, respectively. Most of these dogs succumbed to problems unrelated to the arrhythmia and pacemaker implant. One dog was lost to follow-up. Complications associated with permanent transvenous pacemaker implantation included lead dislodgement, infection, hematoma formation, skeletal muscle stimulation, ventricular arrhythmia, migration of the pulse generator, and skin erosion. Lead dislodgement was the most common complication, occurring in 7 of 9 dogs paced using untined electrode leads and in 6 of 30 dogs paced using tined leads. Lead dislodgement did not occur in the only dog paced using an actively fixed endocardial lead. It was concluded that permanent transvenous cardiac pacing is a feasible, less traumatic alternative to epimyocardial pacing in dogs, but that successful use of this technique requires careful implantation technique and anticipation of the potential complications

  16. Permanent iodine-125 implants in malignant gliomas

    International Nuclear Information System (INIS)

    Introduction: Permanent I-125 implants in the primary treatment of malignant gliomas have not been widely utilized in North America. This report summarizes the Detroit experience concerning survival, prognostic factors and toxicity following low dose rate, permanent I-125 implants in the primary treatment of malignant gliomas. Material and Methods: between 1988-1995, 91 patients; 51 non-glioblastoma malignant gliomas (NGM), 40 glioblastoma multiforme (GBM), were implanted as part of the initial treatment. Eighty-one patients received additional partial brain external beam radiation (50-60 Gy); following implant in 61 patients, preceding implant in 20 patients. Ten patients (9 NGM, 1 GBM) underwent implant without addition external beam radiation. Stereotactic treatment planning was used to encompass the contrast-enhancing rim of the tumor visualized by computerized tomography with an initial dose rate of 0.5 Gy/hr with iodine-125, delivering 100 Gy at 1 year and 103.68 Gy at infinity. Results: with a median follow-up of 30 months (range of 3 months to 7.25 years), the 1, 2 and 3 year survival for the NGMs was 79%, 68%, 63%; the 1 and 2 year survival for the GBMs was 35% and 21%. Second surgery in (42(91)) (49%) revealed primarily tumor recurrence in 26 (63%), radiation necrosis in 14 (33%), brain abscess 1 (2%) and skull necrosis in 1 (2%). Adverse prognostic factors identified were GBM pathology, deep tumor location in the corpus callosum or thalamus, and age greater than 60. Conclusions: permanent I-125 implants are associated with a relatively high-quality, long-term survival

  17. [125I]Iodopride

    International Nuclear Information System (INIS)

    Substituted benzamides are currently among the most selective antagonists at dopamine D-2 receptors, and high affinity ligands have been developed by substituting halogens into the aromatic ring of the benzamides. The authors report the high affinity, stereoselective, reversible, and sodium dependent binding of a new iodine-substituted benzamide, called [125I]iodopride, to a membrane preparation from rat corpus striatum. 5 refs.; 1 figure

  18. Occupational exposure of professionals during interstitial permanent prostate brachytherapy implants

    Energy Technology Data Exchange (ETDEWEB)

    Pirraco, R.; Pereira, A.; Viterbo, T.; Cavaco, A. [Instituto Portugues de Oncologia Francisco Gentil, Centro R egional de Oncologia do Porto, SA, Porto (Portugal)

    2006-07-01

    Full text of publication follows: Introduction: In this study we present dose measurements for professionals exposed during interstitial 125 I permanent prostate brachytherapy implants. Methods and Materials: The implant technique used was intra operative real time using strand and loose seeds. The professionals inside the operating room are an oncologist, a radiologist, a physicist, a nurse and an anesthesiologist. The oncologist and the physicist contact directly the loaded needle with radioactive seeds and two types of measurements were taken: total body and extremities (finger) dose. The rest of the team operates at long distances, but measurements were made. To measure total body equivalent dose we use a Berthold Umo LB 123 coupled with a LB 1236-H10 detector, and we recorded dose, time and distance from implant location. Finger dosemeters are thermo -luminescent dosimeter (TLD) rings that were controlled over one month. Results: 50 cases (average number of applications per year) were analysed for extremities measurements and 9 cases for total body measurements (in this case, the results were extrapolated for 50 cases), with an average of 26.1 mCi total activity per implant (in a range of 17.4 - 40.3 mCi). The finger dose was 1.8 mSv for the oncologist and 1.9 mSv for the physicist. The interpolation of total body equivalent dose for the oncologist was 24 mSv, for the radiologist 6 mSv and 9 mSv for the physicist. The rest of the team did not receive anything but background radiation. The annual national limit dose for workers is 20 mSv for total body irradiation, and 500 mSv for extremities. Conclusion: In conclusion we may say that during interstitial permanent prostate brachytherapy implants, total doses received for all groups are not significant when compared to annual limits for Portuguese laws 1. Even so, our main goal is always to get the less possible dose (ALARA principle). References: 1. Decreto Lei n. 180/2002 de 8 de Agosto. (authors)

  19. Occupational exposure of professionals during interstitial permanent prostate brachytherapy implants

    International Nuclear Information System (INIS)

    Full text of publication follows: Introduction: In this study we present dose measurements for professionals exposed during interstitial 125 I permanent prostate brachytherapy implants. Methods and Materials: The implant technique used was intra operative real time using strand and loose seeds. The professionals inside the operating room are an oncologist, a radiologist, a physicist, a nurse and an anesthesiologist. The oncologist and the physicist contact directly the loaded needle with radioactive seeds and two types of measurements were taken: total body and extremities (finger) dose. The rest of the team operates at long distances, but measurements were made. To measure total body equivalent dose we use a Berthold Umo LB 123 coupled with a LB 1236-H10 detector, and we recorded dose, time and distance from implant location. Finger dosemeters are thermo -luminescent dosimeter (TLD) rings that were controlled over one month. Results: 50 cases (average number of applications per year) were analysed for extremities measurements and 9 cases for total body measurements (in this case, the results were extrapolated for 50 cases), with an average of 26.1 mCi total activity per implant (in a range of 17.4 - 40.3 mCi). The finger dose was 1.8 mSv for the oncologist and 1.9 mSv for the physicist. The interpolation of total body equivalent dose for the oncologist was 24 mSv, for the radiologist 6 mSv and 9 mSv for the physicist. The rest of the team did not receive anything but background radiation. The annual national limit dose for workers is 20 mSv for total body irradiation, and 500 mSv for extremities. Conclusion: In conclusion we may say that during interstitial permanent prostate brachytherapy implants, total doses received for all groups are not significant when compared to annual limits for Portuguese laws 1. Even so, our main goal is always to get the less possible dose (ALARA principle). References: 1. Decreto Lei n. 180/2002 de 8 de Agosto. (authors)

  20. Quality of life after permanent prostate implant

    International Nuclear Information System (INIS)

    Purpose: To report on the quality of life in patients who have received a permanent transperineal ultrasound guide prostate implant. There is increasing recognition that prostate cancer therapy impacts significantly on the patients ability to pursue relational, occupational and social interests. With the substantially expanded patient role in directing treatment for prostate cancer, the importance of examining quality of life outcomes in addition to survival has been underscored. Materials and Methods: 51 sequential patients with clinically localized prostate cancer who underwent permanent prostate implantation from September 1995 to October 1996 were evaluated. All patients were clinically staged as T1c or T2a and received implant with Iodine 125 or Palladium 103 as definitive treatment. Data was collected using the EORTC genitourinary group questionnaire and supplemental questions during an interview. Results: Urinary symptoms such as nocturia, frequency and dysuria were the most pronounced in the first two months after implant and then decreased in the majority of patients. The EORTC questionnaire was administered at 6 months and examined urinary quality, sexual quality and perception of symptoms. With regard to urinary quality, 17% had mild dysuria at 6 months and 40% noted that they urinated more frequently than pre implant. No patient had hematuria and 0 % were incontinent. 3% stated that they had occasional loss of minimal urine with severe urgency. Only 2% required intermittent self catheterization after implant secondary to obstructive symptoms. Over 90% were on an alpha blocker post implant for a minimum of 6 weeks. 0% reported psychological distress and 3% noted a disruption in social or family life. 15% experienced some fatigue and 10% noted a decreased functional status but only 1% a decreased role function. Additional questions addressed lifestyle and work issues. 100% would have an implant again as definitive treatment and 98% would recommend the procedure to a friend. Of the patients who had full time employment (38), 96% returned to work after the implant and the majority returned within 5 days. Sexual quality was high in this short follow up after seed implant. 89% of potent patients retained sexual function after implant. 3% noted some discomfort with ejaculation. 12% noticed some decrease in sexual desire. Interestingly, 14% experienced an increase in sexual desire. 79% reported an excellent overall quality of life. Conclusions: While survival is clearly a central goal of treatment for prostate cancer, the nature of this malignancy compels clinical attention to the qualitative content of the patients life after treatment. Permanent prostate implant has a high degree of patient tolerance and patient acceptance. Sexual quality and function are maintained in the majority of patients and they have minimal interruption in their social and economic function. The low morbidity and high quality of life associated with implantation make it a viable treatment option

  1. External beam radiotherapy boosts to reduce the impact caused by edema in prostate permanent seed implants

    International Nuclear Information System (INIS)

    In prostate permanent seed implants, it has been shown that edema caused by the surgical procedure decreases dose coverage and hence may reduce treatment efficacy. This reduction in treatment efficacy has been characterized by an increase in tumour cell survival, and biomathematical models have been developed to calculate the tumour cell survival increases in seed implanted prostates of different edema magnitudes and durations. External beam boosts can be utilized to neutralize the negative impact of edema so that originally desired treatment efficacy can be achieved. In this study, a linear quadratic model is used to determine fractionation sizes of the external beam boosts for both 125I and 103Pd seed implants. Calculations were performed for prostates of different edema magnitudes and durations, and for tumour cells of different repair rates and repopulation rates

  2. Experimental determination of dosimetry parameters for Sinko 125I seed source using a modified polystyrene phantom

    International Nuclear Information System (INIS)

    Successful treatment for permanent implant brachytherapy is based on accurate measurement of dosimetry parameters for the seed sources. Literature describes the application of various types of phantom to determine the AAPM TG-43 dosimetry parameters for permanent implant seeds. Previously we created a new type of phantom used to measure the dosimetry parameters of a high dose-rate 192Ir source. In this study, we modified the phantom to suit to a common type of 125I seed source (Sinko BT-125-1). The dose-rate constant, radial dose function and anisotropy function of this source were measured in detail and compared with the published values of other similar in-design 125I seed sources. The experimental results exhibit fairly small measurement uncertainties and good self-consistency. The modified phantom is demonstrated on the measurement of dosimetry parameters for the Sinko BT-125-1 125I seed, however, it could easily be used for similar measurements of other permanent implantation seed sources.

  3. Permanent Breast Seed Implant Dosimetry Quality Assurance

    International Nuclear Information System (INIS)

    Purpose: A permanent breast seed implant is a novel method of accelerated partial breast irradiation for women with early-stage breast cancer. This article presents pre- and post-implant dosimetric data, relates these data to clinical outcomes, and makes recommendations for those interested in starting a program. Methods and Materials: A total of 95 consecutive patients were accrued into one of three clinical trials after breast-conserving surgery: a Phase I/II trial (67 patients with infiltrating ductal carcinoma); a Phase II registry trial (25 patients with infiltrating ductal carcinoma); or a multi-center Phase II trial for patients with ductal carcinoma in situ (3 patients). Contouring of the planning target volume (PTV) was done on a Pinnacle workstation and dosimetry calculations, including dose–volume histograms, were done using a Variseed planning computer. Results: The mean pre-implant PTV coverage for the V90, V100, V150, and V200 were as follows: 98.8% ± 1.2% (range, 94.5–100%); 97.3% ± 2.1% (range, 90.3–99.9%), 68.8% ± 14.3% (range, 32.7–91.5%); and 27.8% ± 8.6% (range, 15.1–62.3%). The effect of seed motion was characterized by post-implant dosimetry performed immediately after the implantation (same day) and at 2 months after the implantation. The mean V100 changed from 85.6% to 88.4% (p = 0.004) and the mean V200 changed from 36.2% to 48.3% (p 90 of approximately 100%, a V100 between 95% and 100%, and a V200 between 20% and 30%, as these numbers are associated with no local recurrences to date and good patient tolerance. In general, the target volume coverage improved over the duration of the seed therapy. The maximum skin dose, defined as the average dose over the hottest 1 × 1-cm2 surface area, should be limited to 90% of the prescription dose to minimize delayed skin toxicity.

  4. Study of photon angular distribution from a new Best 2300 series 125I source for interstitial brachytherapy

    International Nuclear Information System (INIS)

    125I seeds employed for permanent and temporary interstitial implants exhibit significant radiation fluence anisotropy due to self absorption in the marker and oblique filtration through the encapsulation jacket. A silver wire 125I seed (Model 6711), introduced in 1983 by 3M Company, failed to improve the photon distribution anisotropy. In addition to the known 125I photon spectrum, the new seed emitted two silver characteristic x-rays, lowering the mean photon energy from 28.4 to 27.4 keV. A double wall uniform thickness encapsulated 125I source, laser welded at one end, has been developed for clinical use. The source uses a carbon coated thin tungsten filament for enhanced radiographic visualization. Measurements made by NaI and intrinsic Ge detectors indicate that the 2300 series 125I source emits a pure 125I spectrum. The angular dependence of individual photon peaks and total photon spectrum as well as the corresponding anisotropy factors were measured. The 4? averaged anisotropy factor for the total radiation fluence is 0.92 compared to 0.87 for model 6711 seed. The dose distribution around the new 125I source in water is very isotropic. (author). 11 refs., 8 figs., 2 tabs

  5. Radiation protection procedures and dose to the staff in brachytherapy with permanent implant of the sources

    Energy Technology Data Exchange (ETDEWEB)

    Tosi, G.; Cattani, F.

    2002-07-01

    The treatment of intra capsular prostate cancers with the permanent implantation of low energy sealed radioactive sources (''103 Pd-''125I) offers the same probability of curing the tumours as surgery and external-beam radiotherapy with a minimum incidence of unwanted side-effects. The first attempts of using sealed sources for treating prostate cancers go back to 1917, when Barringer reported the results obtained with the implant of ''236Ra needles. Beginning from that period the interest for prostate brachytherapy has shown a fluctuating trend, due especially to the technological possibilities and to the status of the alternative treatment modalities (surgery, external radiotherapy). The main reason of the substantial failure of brachytherapy as compared to the two other treatment modalities had two main causes: the energy, too high ( E{approx_equal} 840 keV), of {gamma}-radiation emitted by ''226 Ra in equilibrium with its decay products and the lack of imaging techniques able to visualize with sufficient accuracy both the prostate and the arrangement, inside it, of the radioactive sources. The employ of low energy {gamma}-emitting radionuclides began in 1974, when Whitmore et al. working at the Sloan Kettering Memorial Cancer Hospital of New York suggested the use of ''125 I sealed sources for the realisation of interstitial permanent implants. Also this attempt, though reducing the side effects typical of the surgical intervention (incontinence, impotence), did non give the expected results in terms of local control of the disease and, as a consequence, of the survival's length. This partial failure was attributed to the fact that, in most cases the dose distribution inside the target volume was not homogeneous, due to the inadequacy of the available imaging techniques used for checking the real position of the sources, during their manual insertion in the tissues. In the last ten years,however, great progresses have been made in the US{sub i}maging techniques, in the manufacture of suitable sealed sources of ''103 Pd and ''125 I, in the development of computer programs able both to acquire US-images and to calculate and display in real time the dose distribution. In selected cases, the permanent implant of such sources has demonstrated of being alternative to the surgical intervention and even to external conformal radiotherapy. (Author)

  6. Permanent implants in treatment of prostate cancer

    International Nuclear Information System (INIS)

    Low-dose rate brachytherapy (LDR - BT) is one of the radiation methods that is known for several years in treatment of localized prostate cancer. The main idea of this method is to implant small radioactive seeds as a source of radiation, directly into the prostate gland. LDR brachytherapy is applied as a monotherapy and also used along with external beam radiation therapy (EBRT) as a boost. In most cases it is used as a sole radical treatment modality, however not as a palliative treatment. The application of permanent seeds implants is a curative treatment alternative in patients with organ-confined cancer, without extracapsular extension of the tumour. Nowadays three kinds of radionuclide (I-125, Pd-103, Cs-131) are in use worldwide. This technique is particular favorite in United States, in Europe however, high-dose rate brachytherapy method (HDR BT) is more popular in early staged prostate cancer treatment ( as a boost). HDR-BT monotherapy for early stage prostate cancer is still an investigational treatment. As monotherapy LDR-BT seems to be a reliable choice for early stage prostate cancer, according to low morbidity rate good results and short hospitalization. It is curative alternative of radical prostatectomy or external beam radiation (i.e. 3D CRT, IMRT) with comparable long-term survival and biochemical control and most favorable toxicity. The aim of this publication is to describe methods, indications, complications and selected results of prostate cancer LDR brachytherapy. (author)

  7. Iodine-125 seed implantation (permanent brachytherapy) for clinically localized prostate cancer

    International Nuclear Information System (INIS)

    From January 2004 to March 2007, 308 patients with clinically localized prostate cancer were treated using iodine-125 (125I) seed implantation (permanent brachytherapy) at Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences. We evaluated the treatment's efficacy and morbidity in 300 prostate cancer patients who were followed up for more than 1 month after brachytherapy. Based on the National Comprehensive Cancer Network (NCCN) guidelines, patients with a prostate volume of less than 40 ml in transrectal ultrasound imaging were classified as low or intermediate risk. The median patient age was 67 years (range 50 to 79 years), the median prostate-specific antigen (PSA) value before biopsy was 6.95 ng/ml (range 1.13 to 24.7 ng/ml), and the median prostate volume was 24.33 ml (range 9.3 to 41.76 ml). The median follow-up was 18 months (range 1 to 36 months) and the PSA levels decreased in almost all patients after brachytherapy. Although 194 of 300 patients (64.7%) complained of difficulty in urination, pollakisuria/urgency, miction pain, and/or urinary incontinence, all of which might be associated with radiation prostatitis during the first month after brachytherapy, these symptoms gradually improved. 125I seed implantation brachytherapy is safe and effective for localized prostate cancer within short-term follow up. (author)

  8. An analysis of brachytherapy with computed tomography-guided permanent implantation of Iodine-125 seeds for recurrent nonkeratin nasopharyngeal carcinoma

    Directory of Open Access Journals (Sweden)

    Shen X

    2015-05-01

    Full Text Available Xinying Shen,1,2 Yong Li,2 Yanfang Zhang,2 Jian Kong,2 Yanhao Li1 1Department of Interventional Radiology, Nanfang Hospital, Southern Medical University, Guangzhou, 2Department of Interventional Radiology, Shenzhen People’s Hospital, The Second Clinical Medical College of Jinan University, Shenzhen, People’s Republic of China Background: 125I seed implantation is a new method in treatment of nasopharyngeal carcinoma (NPC, and it is worthwhile to evaluate its feasibility. In this study, we performed brachytherapy with computed tomography (CT-guided permanent implantation of 125I seeds in the treatment of patients with the recurrence of NPC.Methods: A total 30 patients (20 male and ten female at the median age of 55 (range 25–80 years were diagnosed with recurrent nonkeratin NPC, with a total 38 lesions and a short disease-free interval (median ~11 months after primary radiotherapy alone or combined with chemotherapy. Patients received CT scan, starting from 2 months after the treatment. Follow-up was conducted for ~2–38 months to observe the local control rate and overall survival rate. We also analyzed the possible correlation between survival periods and the status of recurrent tumors.Results: The local control rates at 6, 12, 24, 30, and 36 months after the procedure of 125I seed implantation were 86.8%, 73.7%, 26.3%, 15.8%, and 5.3%, respectively. The overall 1-, 2-, and 3-year survival rates were 80.0% (24/30, 30.0% (9/30, and 6.7% (2/30, respectively, with a median survival period of 18 months (17.6±8.6 months. Interestingly, the survival periods of the patients who had primary radiotherapy with or without chemotherapy were 15.8±7.9 and 24.3±7.9 months, respectively. Kaplan–Meier survival analysis demonstrated that ?2 (log rank was 7.555, with very significant difference (P<0.01. The survival periods of patients in tumor stages I, II, III, and IV were 25.4±8.7, 19.8±9.4, 16.1±4.5, and 12.8±7.8 months, respectively, with significant differences (P<0.05.Conclusion: Our data suggest that the survival period of recurrent NPC patients after 125I seed implantation is inversely related to the tumor stages of the recurrence but not to chemotherapy after the primary radiotherapy. Therefore, CT-guided 125I seed implantation can be set for treatment of recurrent NPC, for better survival rate with minimal damage. Keywords: CT-guided 125I seed, radiochemotherapy, NPC 

  9. 78 FR 41125 - Interim Enforcement Policy for Permanent Implant Brachytherapy Medical Event Reporting

    Science.gov (United States)

    2013-07-09

    ...Interim Enforcement Policy for Permanent Implant Brachytherapy Medical Event Reporting...occurring under an NRC licensee's permanent implant brachytherapy program. This interim policy...that are authorized to perform permanent implant brachytherapy. DATES: This policy...

  10. Influence of source batch Sk dispersion on dosimetry for prostate cancer treatment with permanent implants

    DEFF Research Database (Denmark)

    Perez-Calatayud, J; Casares-Magaz, O

    2015-01-01

    PURPOSE: In clinical practice, specific air kerma strength (SK) value is used in treatment planning system (TPS) permanent brachytherapy implant calculations with (125)I and (103)Pd sources; in fact, commercial TPS provide only one SK input value for all implanted sources and the certified shipment average is typically used. However, the value for SK is dispersed: this dispersion is not only due to the manufacturing process and variation between different source batches but also due to the classification of sources into different classes according to their SK values. The purpose of this work is to examine the impact of SK dispersion on typical implant parameters that are used to evaluate the dose volume histogram (DVH) for both planning target volume (PTV) and organs at risk (OARs). METHODS: The authors have developed a new algorithm to compute dose distributions with different SK values for each source. Three different prostate volumes (20, 30, and 40 cm(3)) were considered and two typical commercial sources of different radionuclides were used. Using a conventional TPS, clinically accepted calculations were made for (125)I sources; for the palladium, typical implants were simulated. To assess the many different possible SK values for each source belonging to a class, the authors assigned an SK value to each source in a randomized process 1000 times for each source and volume. All the dose distributions generated for each set of simulations were assessed through the DVH distributions comparing with dose distributions obtained using a uniform SK value for all the implanted sources. The authors analyzed several dose coverage (V100 and D90) and overdosage parameters for prostate and PTV and also the limiting and overdosage parameters for OARs, urethra and rectum. RESULTS: The parameters analyzed followed a Gaussian distribution for the entire set of computed dosimetries. PTV and prostate V100 and D90 variations ranged between 0.2% and 1.78% for both sources. Variations for the overdosage parameters V150 and V200 compared to dose coverage parameters were observed and, in general, variations were larger for parameters related to (125)I sources than (103)Pd sources. For OAR dosimetry, variations with respect to the reference D0.1cm(3) were observed for rectum values, ranging from 2% to 3%, compared with urethra values, which ranged from 1% to 2%. CONCLUSIONS: Dose coverage for prostate and PTV was practically unaffected by SK dispersion, as was the maximum dose deposited in the urethra due to the implant technique geometry. However, the authors observed larger variations for the PTV V150, rectum V100, and rectum D0.1cm(3) values. The variations in rectum parameters were caused by the specific location of sources with SK value that differed from the average in the vicinity. Finally, on comparing the two sources, variations were larger for (125)I than for (103)Pd. This is because for (103)Pd, a greater number of sources were used to obtain a valid dose distribution than for (125)I, resulting in a lower variation for eachSK value for each source (because the variations become averaged out statistically speaking).

  11. Image fusion techniques in permanent seed implantation

    Directory of Open Access Journals (Sweden)

    Alfredo Polo

    2010-10-01

    Full Text Available Over the last twenty years major software and hardware developments in brachytherapy treatment planning, intraoperative navigation and dose delivery have been made. Image-guided brachytherapy has emerged as the ultimate conformal radiation therapy, allowing precise dose deposition on small volumes under direct image visualization. In thisprocess imaging plays a central role and novel imaging techniques are being developed (PET, MRI-MRS and power Doppler US imaging are among them, creating a new paradigm (dose-guided brachytherapy, where imaging is used to map the exact coordinates of the tumour cells, and to guide applicator insertion to the correct position. Each of these modalities has limitations providing all of the physical and geometric information required for the brachytherapy workflow.Therefore, image fusion can be used as a solution in order to take full advantage of the information from each modality in treatment planning, intraoperative navigation, dose delivery, verification and follow-up of interstitial irradiation.Image fusion, understood as the visualization of any morphological volume (i.e. US, CT, MRI together with an additional second morpholo gical volume (i.e. CT, MRI or functional dataset (functional MRI, SPECT, PET, is a well known method for treatment planning, verification and follow-up of interstitial irradiation. The term image fusion is used when multiple patient image datasets are registered and overlaid or merged to provide additional information. Fused images may be created from multiple images from the same imaging modality taken at different moments (multi-temporalapproach, or by combining information from multiple modalities. Quality means that the fused images should provide additional information to the brachythe rapy process (diagnosis and staging, treatment planning, intraoperative imaging, treatment delivery and follow-up that cannot be obtained in other ways. In this review I will focus on the role of image fusion for permanent seed implantation.

  12. Dose calculation for permanent prostate implants incorporating spatially anisotropic linearly time-resolving edema

    International Nuclear Information System (INIS)

    Purpose: The objectives of this study were (i) to develop a dose calculation method for permanent prostate implants that incorporates a clinically motivated model for edema and (ii) to illustrate the use of the method by calculating the preimplant dosimetry error for a reference configuration of 125I, 103Pd, and 137Cs seeds subject to edema-induced motions corresponding to a variety of model parameters. Methods: A model for spatially anisotropic edema that resolves linearly with time was developed based on serial magnetic resonance imaging measurements made previously at our center to characterize the edema for a group of n=40 prostate implant patients [R. S. Sloboda et al., ''Time course of prostatic edema post permanent seed implant determined by magnetic resonance imaging,'' Brachytherapy 9, 354-361 (2010)]. Model parameters consisted of edema magnitude, ?, and period, T. The TG-43 dose calculation formalism for a point source was extended to incorporate the edema model, thus enabling calculation via numerical integration of the cumulative dose around an individual seed in the presence of edema. Using an even power piecewise-continuous polynomial representation for the radial dose function, the cumulative dose was also expressed in closed analytical form. Application of the method was illustrated by calculating the preimplant dosimetry error, REpreplan, in a 5x5x5 cm3 volume for 125I (Oncura 6711), 103Pd (Theragenics 200), and 131Cs (IsoRay CS-1) seeds arranged in the Radiological Physics Center test case 2 configuration for a range of edema relative magnitudes (?=[0.1,0.2,0.4,0.6,1.0]) and periods (T=[28,56,84] d). Results were compared to preimplant dosimetry errors calculated using a variation of the isotropic edema model developed by Chen et al. [''Dosimetric effects of edema in permanent prostate seed implants: A rigorous solution,'' Int. J. Radiat. Oncol., Biol., Phys. 47, 1405-1419 (2000)]. Results: As expected, REpreplan for our edema model indicated underdosage in the calculation volume with a clear dependence on seed and calculation point positions, and increased with increasing values of ? and T. Values of REpreplan were generally larger near the ends of the virtual prostate in the RPC phantom compared with more central locations. For edema characteristics similar to the population average values previously measured at our center, i.e., ?=0.2 and T=28 d, mean values of REpreplan in an axial plane located 1.5 cm from the center of the seed distribution were 8.3% for 131Cs seeds, 7.5% for 103Pd seeds, and 2.2% for 125I seeds. Maximum values of REpreplan in the same plane were about 1.5 times greater. Note that detailed results strictly apply only for loose seed implants where the seeds are fixed in tissue and move in synchrony with that tissue. Conclusions: A dose calculation method for permanent prostate implants incorporating spatially anisotropic linearly time-resolving edema was developed for which cumulative dose can be written in closed form. The method yields values for REpreplan that differ from those for spatially isotropic edema. The method is suitable for calculating pre- and postimplant dosimetry correction factors for clinical seed configurations when edema characteristics can be measured or estimated.

  13. Dose calculation for permanent prostate implants incorporating spatially anisotropic linearly time-resolving edema

    Energy Technology Data Exchange (ETDEWEB)

    Monajemi, T. T.; Clements, Charles M.; Sloboda, Ron S. [Department of Medical Physics, Cross Cancer Institute, Edmonton, Alberta T6G 1Z2 (Canada) and Department of Oncology, University of Alberta, Edmonton, Alberta T6G 2R3 (Canada); Department of Physics, University of Alberta, Edmonton, Alberta T6G 2R3 (Canada); Department of Medical Physics, Cross Cancer Institute, Edmonton, Alberta T6G 1Z2 (Canada); Department of Oncology, University of Alberta, Edmonton, Alberta T6G 2R3 (Canada) and Department of Physics, University of Alberta, Edmonton, Alberta T6G 2R3 (Canada)

    2011-04-15

    Purpose: The objectives of this study were (i) to develop a dose calculation method for permanent prostate implants that incorporates a clinically motivated model for edema and (ii) to illustrate the use of the method by calculating the preimplant dosimetry error for a reference configuration of {sup 125}I, {sup 103}Pd, and {sup 137}Cs seeds subject to edema-induced motions corresponding to a variety of model parameters. Methods: A model for spatially anisotropic edema that resolves linearly with time was developed based on serial magnetic resonance imaging measurements made previously at our center to characterize the edema for a group of n=40 prostate implant patients [R. S. Sloboda et al., ''Time course of prostatic edema post permanent seed implant determined by magnetic resonance imaging,'' Brachytherapy 9, 354-361 (2010)]. Model parameters consisted of edema magnitude, {Delta}, and period, T. The TG-43 dose calculation formalism for a point source was extended to incorporate the edema model, thus enabling calculation via numerical integration of the cumulative dose around an individual seed in the presence of edema. Using an even power piecewise-continuous polynomial representation for the radial dose function, the cumulative dose was also expressed in closed analytical form. Application of the method was illustrated by calculating the preimplant dosimetry error, RE{sub preplan}, in a 5x5x5 cm{sup 3} volume for {sup 125}I (Oncura 6711), {sup 103}Pd (Theragenics 200), and {sup 131}Cs (IsoRay CS-1) seeds arranged in the Radiological Physics Center test case 2 configuration for a range of edema relative magnitudes ({Delta}=[0.1,0.2,0.4,0.6,1.0]) and periods (T=[28,56,84] d). Results were compared to preimplant dosimetry errors calculated using a variation of the isotropic edema model developed by Chen et al. [''Dosimetric effects of edema in permanent prostate seed implants: A rigorous solution,'' Int. J. Radiat. Oncol., Biol., Phys. 47, 1405-1419 (2000)]. Results: As expected, RE{sub preplan} for our edema model indicated underdosage in the calculation volume with a clear dependence on seed and calculation point positions, and increased with increasing values of {Delta} and T. Values of RE{sub preplan} were generally larger near the ends of the virtual prostate in the RPC phantom compared with more central locations. For edema characteristics similar to the population average values previously measured at our center, i.e., {Delta}=0.2 and T=28 d, mean values of RE{sub preplan} in an axial plane located 1.5 cm from the center of the seed distribution were 8.3% for {sup 131}Cs seeds, 7.5% for {sup 103}Pd seeds, and 2.2% for {sup 125}I seeds. Maximum values of RE{sub preplan} in the same plane were about 1.5 times greater. Note that detailed results strictly apply only for loose seed implants where the seeds are fixed in tissue and move in synchrony with that tissue. Conclusions: A dose calculation method for permanent prostate implants incorporating spatially anisotropic linearly time-resolving edema was developed for which cumulative dose can be written in closed form. The method yields values for RE{sub preplan} that differ from those for spatially isotropic edema. The method is suitable for calculating pre- and postimplant dosimetry correction factors for clinical seed configurations when edema characteristics can be measured or estimated.

  14. Placement of 125I implants with the da Vinci robotic system after video-assisted thoracoscopic wedge resection: A feasibility study

    International Nuclear Information System (INIS)

    Purpose: To evaluate the feasibility of using the da Vinci robotic system for radioactive seed placement in the wedge resection margin of pigs' lungs. Methods and materials: Video-assisted thoracoscopic wedge resection was performed in the upper and lower lobes in pigs. Dummy 125I seeds embedded in absorbable sutures were sewn into the resection margin with the aid of the da Vinci robotic system without complications. In the 'loop technique,' the seeds were placed in a cylindrical pattern; in the 'longitudinal,' they were above and lateral to the resection margin. Orthogonal radiographs were taken in the operating room. For dose calculation, Variseed 66.7 (Build 11312) software was used. Results: With looping seed placement, in the coronal view, the dose at 1 cm from the source was 97.0 Gy; in the lateral view it was 107.3 Gy. For longitudinal seed placement, the numbers were 89.5 Gy and 70.0 Gy, respectively. Conclusion: Robotic technology allows direct placement of radioactive seeds into the resection margin by endoscopic surgery. It overcomes the technical difficulties of manipulating in the narrow chest cavity. With the advent of robotic technology, new options in the treatment of lung cancer, as well as other malignant tumors, will become available

  15. Adsorption of iodide on silver rods for {sup 125}I seed preparation

    Energy Technology Data Exchange (ETDEWEB)

    Lee, J. H.; Park, U. J.; Yu, K. H. [Dongguk University, Seoul (Korea, Republic of); Lee, J. S.; Choi, K. H.; Nam, S. S.; Seo, J. S.; Choi, S. J.; Son, K. J. [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2011-10-15

    Recently, the rate of prostate cancer is increasing rapidly in Korea. Brachytherapy using {sup 125}I seeds has drawn attention as one of the treatment options of this type of cancer. {sup 125}I is a radionuclide, which emits 27 keV and 31 keV X-rays and 35 keV {gamma}-ray with a half-life of 59.4 days. This radioisotope is produced by the bombardment of neutrons on the {sup 124}Xe target and decays via electron capture to {sup 125}Te. The brachytherapy sources are fabricated as seeds and implanted permanently to the prostate. The seed consists of a titanium capsule as a shell with a dimension of 0.8 mm in external diameter, 0.05 mm in wall thickness and 4.5 mm in length. A silver (Ag) rod with a dimension of 3 mm in length and 0.5 mm in diameter is used as the radioactive core after adsorption of {sup 125}I and is placed in the shell. The silver rod also acts as an X-ray marker to visualize by X-ray imaging and determine the location of seeds in the prostate. Currently, the supply of {sup 125}I seeds depends only on imports. Hence, national research and development are needed for local production. This research work is carried out to find the optimum conditions in the preparation of the radioactive core, more specifically in the adsorption of iodide on the silver rods

  16. Adsorption of iodide on silver rods for 125I seed preparation

    International Nuclear Information System (INIS)

    Recently, the rate of prostate cancer is increasing rapidly in Korea. Brachytherapy using 125I seeds has drawn attention as one of the treatment options of this type of cancer. 125I is a radionuclide, which emits 27 keV and 31 keV X-rays and 35 keV ?-ray with a half-life of 59.4 days. This radioisotope is produced by the bombardment of neutrons on the 124Xe target and decays via electron capture to 125Te. The brachytherapy sources are fabricated as seeds and implanted permanently to the prostate. The seed consists of a titanium capsule as a shell with a dimension of 0.8 mm in external diameter, 0.05 mm in wall thickness and 4.5 mm in length. A silver (Ag) rod with a dimension of 3 mm in length and 0.5 mm in diameter is used as the radioactive core after adsorption of 125I and is placed in the shell. The silver rod also acts as an X-ray marker to visualize by X-ray imaging and determine the location of seeds in the prostate. Currently, the supply of 125I seeds depends only on imports. Hence, national research and development are needed for local production. This research work is carried out to find the optimum conditions in the preparation of the radioactive core, more specifically in the adsorption of iodide on the silver rods

  17. MR and CT image fusion for postimplant analysis in permanent prostate seed implants

    International Nuclear Information System (INIS)

    Purpose: To compare the outcome of two different image-based postimplant dosimetry methods in permanent seed implantation. Methods and materials: Between October 1999 and October 2002, 150 patients with low-risk prostate carcinoma were treated with 125I and 103Pd in our institution. A CT-MRI image fusion protocol was used in 21 consecutive patients treated with exclusive brachytherapy. The accuracy and reproducibility of the method was calculated, and then the CT-based dosimetry was compared with the CT-MRI-based dosimetry using the dose-volume histogram (DVH) related parameters recommended by the American Brachytherapy Society and the American Association of Physicists in Medicine. Results: Our method for CT-MRI image fusion was accurate and reproducible (median shift 100 = 82% vs. 88%, p 90 = 96% vs. 115%, p < 0.05. Those results depend on the institutional implant technique and reflect the importance of lowering inter- and intraobserver discrepancies when outlining prostate and organs at risk for postimplant dosimetry. Conclusions: Computed tomography-MRI fused images allow accurate determination of prostate size, significantly improving the dosimetric evaluation based on DVH analysis. This provides a consistent method to judge a prostate seed implant's quality

  18. Prophylactic urethral stenting with Memokath® 028SW in prostate cancer patients undergoing prostate 125I seed implants: phase I/II study

    OpenAIRE

    Samuel T. Chao; Kenneth Angermeier; Klein, Eric A.; Reddy, Chandana A.; James C. Ulchaker; Andrew Stephenson; Steven Campbell; Ciezki, Jay P.

    2011-01-01

    Purpose: To study the feasibility/toxicity of urethral stenting with the Memokath® 028SW stent in patients undergoing prostate implant (PI) for prostate adenocarcinoma. Material and methods: An Investigational Device Exemption from the Food and Drug Administration (FDA) and institutional review board (IRB) approval were obtained. Twenty patients enrolled. Baseline American Urological Association (AUA) score was obtained prior to PI. Follow-up information was obtained with weekly phone calls f...

  19. Validation of implant stability: A measure of implant permanence

    Directory of Open Access Journals (Sweden)

    Neha Mall

    2011-01-01

    Full Text Available Implant stability is a requisite characteristic of osseointegration. Without it, long-term success cannot be achieved. Continuous monitoring in a quantitative and objective manner is important to determine the status of implant stability. Measurement of implant stability is a valuable tool for making decisions pertaining to treatment protocol and also improves dentist-patient communication. Owing to the invasive nature of histological analysis, various others methods have been proposed like radiographs, cutting torque resistance, reverse torque, modal analysis, resonance frequency analysis and Implatest® . This review focuses on objectives and various methods to evaluate implant stability.

  20. Permanent 125iodine implants for recurrent malignant gliomas

    International Nuclear Information System (INIS)

    Purpose: To determine the efficacy and toxicity of permanent 125iodine implants for recurrent malignant gliomas. Methods and Materials: Between January 1989 and January:, 59 patients with histologically confirmed recurrent malignant gliomas (22 nonglioblastoma malignant gliomas, 37 glioblastoma multiforme at the time of implant) received a permanent 125iodine implant. Patients ranged in age from 13-74 years. The median ages for the overall group, nonglioblastoma (nonGBM), and glioblastoma (GBM) groups was 47 years, 39 years, and 53 years, respectively. Results: With a median follow-up of 40 months, the median survival for the 59 total patients is 1.34 years; nonGBM 2.04 years, GBM 0.9 years. Factors predictive for poor prognosis were GBM histology, age 60 years or more, target volume 17 cc or more, and/or tumor location within the corpus callosum or thalamus. Reoperations have been performed in 24 (40%) patients; 15 (25%) for tumor progression; 3 (5%) for radiation necrosis; 2 (3%) for skull necrosis/infection, and 4 (7%) for other reasons (Ommaya reservoir insertion, catheter removal, hematoma evacuation). Conclusion: Permanent 125iodine implants in selected patients with recurrent malignant gliomas are associated with reasonable long-term survival and a low risk of complications. Given the low incidence of radiation necrosis, future plans are to increase dose rate and/or total dose delivered with the permanent implant

  1. Prophylactic urethral stenting with Memokath® 028SW in prostate cancer patients undergoing prostate 125I seed implants: phase I/II study

    Directory of Open Access Journals (Sweden)

    Samuel T. Chao

    2011-03-01

    Full Text Available Purpose: To study the feasibility/toxicity of urethral stenting with the Memokath® 028SW stent in patients undergoing prostate implant (PI for prostate adenocarcinoma. Material and methods: An Investigational Device Exemption from the Food and Drug Administration (FDA and institutional review board (IRB approval were obtained. Twenty patients enrolled. Baseline American Urological Association (AUA score was obtained prior to PI. Follow-up information was obtained with weekly phone calls for the first 12 weeks and biweekly calls for the next 12 weeks to assess toxicity and AUA score. Removal of the stent was planned at six months after PI, or earlier due to excessive toxicity/patient request. Results: Median age was 66.5 years. The median prostate volume was 39 cc (range: 10-90. The median baseline AUA score was 7.5 (range: 1-21. Three patients required intermittent self-catheterization (ISC within 3 days after PI. No patients required ISC beyond day 3 after PI. The median duration of ISC was 1 day (range: 1-2. AUA scores returned to baseline values 6 weeks after PI. The week 6 AUA score was 10 (range: 4-16. Seven patients (35% underwent early removal because of patient preference. The reasons were: incontinence (n = 3, discomfort (n = 2, hematuria (n = 1, and obstructive symptoms (n = 1. The median time of stent removal in these patients was 13.9 weeks (range: 0.9-21.4. Thirteen patients (65% had ISC and/or urinary catheterization post stent removal. Median time for ISC use was 10 days (range: 1-90. Conclusions: Urethral stenting with Memokath® in patients undergoing PI was feasible, but resulted in relatively high rate of urinary incontinence and discomfort. Given the adverse effects experienced by patients of this study, further studies should focus only on patients with highest risk of urinary obstruction from PI or those with obstruction needing ISC.

  2. Cell scale 125I microdosimetry

    International Nuclear Information System (INIS)

    The full text of the publication follows. The aim of this study is to derive microdosimetric data from 125I Auger electron irradiation at cellular and subcellular scales within the context of Radioimmunotherapy (RIT). 125I decays through electronic capture and internal conversion processes, resulting in the emission of Auger electron cascades at the end of the process. The energy of 125I Auger electrons is mainly between some eV and 1 keV, resulting in a short path length in biological matter (from about 2 nm to 500 nm) when compared to average cell dimensions. Preclinical cell experiments performed at IRCM [1][2] showed strong differences in cellular response depending on the position of 125I labeled antibodies. This may be due to large statistical fluctuations of energy deposition within the target cell and, consequently, within radiosensitive organelles like nucleus, membrane or mitochondria. To understand the fundamental mechanisms of radiation damage at the cellular scale in the context of RIT, we decided to use Monte-Carlo methods to give account of the stochastic nature of energy deposition from Auger electrons at the subcellular scale. The first part of our study will compare three Monte-Carlo codes at low energy electrons: -) Geant4DNA, a recent extension of the general Monte-Carlo code Geant4 for very low energies, from a few eV to TeV [3]; -) CPA100, a step-by-step Monte-Carlo code developed by Terrissol in Toulouse down to 10 eV [4]; -) PENELOPE version 2008.1 for energies from 50 eV to 1 GeV [5]. Then, realistic cells and sources configurations will be modeled for a realistic 125I Auger electron emission spectrum in Geant4DNA in order to derive microdosimetric parameters such as specific or lineal energy. References: [1] Pouget J.P., Santoro L., Raymond L., Chouin N., Bardies M., Bascoul-Mollevi C., Huguet H., Azria D., Kotzki P.O., Pelegrin M., Vives E. and Pelegrin A., 'Cell membrane is a more sensitive target than cytoplasm to dense ionization produced by Auger electrons', Radiat. Res., vol. 170(2), p. 192-200 (2008); [2] Santoro L., Boutaleb S., Garambois V., Bascoul-Mollevi C., Boudousq V., Kotzki P.O., Pelegrin M., Navarro-Teulon I., Pelegrin A., Pouget J.P., 'Non-internalizing monoclonal antibodies are suitable candidates for 125I radioimmunotherapy of small-volume peritoneal carcinomatosis', J. Nucl Med, vol. 50(12), p. 2033-2041 (2009); [3] Chauvie S., Francis Z., Guatelli S., Incerti B., Mascialino B., Moretto P., Nieminen P., Pia M.G., 'Geant4 Physics Processes for Microdosimetry Simulation: Design Foundation and Implementation of the First Set of Models', IEE Trans. Nucl. Sc., vol.54(6), P. 2619-2628 (2007); [4] Terrissol M., Beaudre A., 'Simulation of space and time evolution of radiolytic species induced by electrons in water', Rad. Prot. Dos., vol.31(1), p.175-177 (1990); [5] Baro J., Sempau J., Fernandez-Varea J.M., Salvat F., 'PENELOPE: An algorithm for Monte Carlo simulation of the penetration and energy loss of electrons and positrons in matter', Nucl. Instr. And Meth. Phys. Res., vol.100(1), p.31-46 (1995). (authors)

  3. 192Ir or 125I prostate brachytherapy as a boost to external beam radiotherapy in locally advanced prostatic cancer: A dosimetric point of view

    International Nuclear Information System (INIS)

    Purpose: This work aims at comparing the dosimetric possibilities of 125I or 192Ir prostate brachytherapy (Bt) as a boost to external beam radiotherapy in the treatment of locally advanced adenocarcinoma. Methods and materials: From 1/1997 to 12/2002, 260 patients were treated. Until 12/2001 a low dose rate (LDR) treatment with 192Ir wires was used, later replaced by a high dose rate (HDR) delivered with an 192Ir stepping source technology. For the present work, we selected 40 patients including the last 20 treated, respectively, by LDR and HDR. The planning CT Scans of all these 40 patients were transferred into the 3D ProwessR system for 125I permanent implants design according to the Seattle method. The reference data for dosimetric comparisons were the V100 and the prescribed dose for 192Ir as well as the dose delivered with 125I techniques to the 192Ir V100. We compared V100-150 data as well as doses to the organs at risks (OR) and cold spots (CS). Results: The V100 is 85.3±8% for 192Ir LDR and 96±2% for HDR techniques (P125I, the 192Ir LDR mode induces higher hyperdosage volumes inside the CTV but also more CS, while maximal doses to urethra and rectum are, respectively, 17 and 39% less with 125I (P192Ir HDR mode, 125I Bt induces higher hyperdosage volumes and slightly more CS deliberately planned around the bladder neck. If delivered doses to urethra are identical, those to the 20% anterior part of the rectum are 33% less with 125I (P125I Bt technique was only possible in 24 out of the 40 patients studied due to pelvic bone arch interference. Conclusions: At the present time, there is no evident dosimetric superiority of one Bt method when all the criteria are taken into account. However, improving Bt techniques to implant any prostatic size could found the superiority of the 125I or permanent implants. 125I indeed allows large hyperdosage volumes inside the CTV in comparison with 192Ir HDR techniques while lowering doses to OR and minimizing CS

  4. Permanent and temporary pacemaker implantation after orthotopic heart transplantation

    Scientific Electronic Library Online (English)

    Fernando, Bacal; Edimar A., Bocchi; Marcelo L. C., Vieira; Neusa, Lopes; Luiz Felipe, Moreira; Alfredo, Fiorelli; Roberto, Costa; Martino, Martinelli; Noedir A. G., Stolf; Giovanni, Bellotti; José Antonio F., Ramires.

    2000-01-01

    Full Text Available PURPOSE:To determine the indication for and incidence and evolution of temporary and permanent pacemaker implantation in cardiac transplant recipients. METHODS: A retrospective review of 114 patients who underwent orthotopic heart transplantation InCor (Heart Institute USP BR) between March 1985 and [...] May 1993. We studied the incidence of and indication for temporary pacing, the relationship between pacing and rejection, the need for pemanent pacing and the clinical follow-up. RESULTS: Fourteen of 114 (12%)heart transplant recipients required temporary pacing and 4 of 114 (3.5%) patients required permanent pacing. The indication for temporary pacing was sinus node dysfunction in 11 patients (78.5%) and atrioventricular (AV) block in 3 patients (21.4%). The indication for permanent pacemaker implantation was sinus node dysfunction in 3 patients (75%) and atrioventricular (AV) block in 1 patient (25%). We observed rejection in 3 patients (21.4%) who required temporary pacing and in 2 patients (50%) who required permanent pacing. The previous use of amiodarone was observed in 10 patients (71.4%) with temporary pacing. Seven of the 14 patients (50%) died during follow-up. CONCLUSION: Sinus node dysfunction was the principal indication for temporary and permanent pacemaker implantation in cardiac transplant recipients. The need for pacing was related to worse prognosis after cardiac transplantation.

  5. Permanent and temporary pacemaker implantation after orthotopic heart transplantation

    Directory of Open Access Journals (Sweden)

    Bacal Fernando

    2000-01-01

    Full Text Available PURPOSE:To determine the indication for and incidence and evolution of temporary and permanent pacemaker implantation in cardiac transplant recipients. METHODS: A retrospective review of 114 patients who underwent orthotopic heart transplantation InCor (Heart Institute USP BR between March 1985 and May 1993. We studied the incidence of and indication for temporary pacing, the relationship between pacing and rejection, the need for pemanent pacing and the clinical follow-up. RESULTS: Fourteen of 114 (12%heart transplant recipients required temporary pacing and 4 of 114 (3.5% patients required permanent pacing. The indication for temporary pacing was sinus node dysfunction in 11 patients (78.5% and atrioventricular (AV block in 3 patients (21.4%. The indication for permanent pacemaker implantation was sinus node dysfunction in 3 patients (75% and atrioventricular (AV block in 1 patient (25%. We observed rejection in 3 patients (21.4% who required temporary pacing and in 2 patients (50% who required permanent pacing. The previous use of amiodarone was observed in 10 patients (71.4% with temporary pacing. Seven of the 14 patients (50% died during follow-up. CONCLUSION: Sinus node dysfunction was the principal indication for temporary and permanent pacemaker implantation in cardiac transplant recipients. The need for pacing was related to worse prognosis after cardiac transplantation.

  6. PSA bounce after permanent implant prostate brachytherapy may mimic a biochemical failure

    International Nuclear Information System (INIS)

    Purpose. To assess the frequency of the PSA 'bouncing' phenomenon after a significant follow-up in a series of patients treated by j permanent implant brachytherapy for a prostate cancer. To look for the clinical and dosimetric parameters possibly linked to this transitory secondary PSA increase. To evaluate in which percentage of cases this bouncing could have mimicked a biochemical relapse according to the ASTRO consensus criteria. Patients and methods. From January 1999, to December 2001, 295 patients were treated by a permanent prostate implantation (real-time technique, with free 125I seeds- Isoseed Bebig-) by the Institut Curie-Hopital Cochin-Hopital Necker Paris group. The mean follow-up is 40.3 months (9--66 months). The PSA level was regularly checked, at least every 6 months. We defined as a 'bouncing' all increase in PSA, starting at 0.1 ng/ml, subsequently followed by a spontaneous (without any treatment) decrease, with return to the previous level or lower. We particularly focused on the patients fulfilling the criteria for a biochemical relapse according to the ASTRO consensus (Three successive increases in PSA). A multivariate analysis tried to identify independent factors among the usual clinical and dosimetric parameters. Results. In our series, 161 patients (55%) showed a transitory PSA increase (bouncing) of at least 0.1 ng/ml; 145 patients (49%) a bouncing of 0.2 ng/ml, 93 patients (32%) a bouncing of 0.4 ng/ml and 43 patients (15%) a bouncing of at least 1 ng/ml. Mean PSA bounce was 0.8 ng/ml (0.1 .1), and mean time to bounce was 19 months. Thirty-two patients (11% of the total number) presented three successive PSA increases with a significant (3 months) interval between the dosages, and therefore were to be considered as being in biochemical relapse according to the ASTRO consensus criteria. Actually, among those 32 patients, 18 (56%) subsequently showed a complete normalization of their PSA, without any treatment. Ten patients went on increasing their PSA, and were considered to be really in biochemical relapse. For the last 4 patients, the situation still remains ambiguous. In multivariate analysis, age 200 Gy (P 200 Gy were found to be independent factors predicting for such a secondary transitory increase in PSA. Interestingly, among 32 patients fulfilling the classical criteria of the ASTRO for a biochemical relapse, 18 (560/0) subsequently showed a spontaneous PSA decrease, demonstrating that the ASTRO consensus is not well adapted to the biochemical follow-up of our patients undergoing permanent implant prostate Brachytherapy. (authors)

  7. The determination of radiobiologically optimized half-lives for radionuclides used in permanent brachytherapy implants

    International Nuclear Information System (INIS)

    Purpose: To use tumor growth kinetics and other biologic parameters in an extended version of the linear-quadratic (LQ) formulation to determine radiobiologically optimized half-lives of radionuclides which might be used in permanent brachytherapy implants. Methods and Materials: A version of the LQ model suitable for the analysis of permanent brachytherapy implants has been modified to investigate the radionuclide half-lives that will maximize the biologically effective dose (BED) delivered to tumors with repopulation rates (K values) in the range 0.01-1.1 Gyday-1. The method assumes that part of the physical dose delivered to the tumor may be radiobiologically wasted because of the repopulation phenomenon, whereas adjacent normal tissues will exhibit little or no wastage. To perform the analysis, it is necessary to stipulate ?/? ratios and sublethal damage recovery rates together with the normal tissue tolerance BED. The analysis also takes into account a range of likely relative biological effectiveness (RBE) values. Results: Rapidly growing tumors require the shortest radionuclide half-lives, but even slow-growing tumors such as prostate adenocarcinomas can be satisfactorily treated with radionuclides possessing half-lives substantially less than that associated with I125. The likelihood that prostate tumors possess an ?/? value which is comparable with, or lower than, that associated with late-responding normal tissues would also mitigate against the use of long-lived radionuclides. Although a number of parameter assumptions are involved, the results suggest that, for a wide range of tumor types, shorter-lived radionuclides are more versatile for achieving reasonable clinical results. The theoretically derived optimum half-lives typically range from around 0-5 days for fast-repopulating tumors (K 1.1 Gyday-1) to approximately 14-50 days for slow-growing tumors (K ? 0.1 Gyday-1 or less). For prostate implantation, 103Pd is overall a better choice than 125I. Conclusion: With so many variables and parameter uncertainties, it is not appropriate to attempt to define optimum radionuclide half-lives too closely. However, this study suggests that half-lives in the approximate range 4-17 days are likely to be significantly better for a wide range of tumor types for which the radiobiologic characteristics may not be precisely known in advance

  8. Routine chest radiography after permanent pacemaker implantation: Is it necessary?

    Directory of Open Access Journals (Sweden)

    Edwards N

    2005-01-01

    Full Text Available Background and Aims: Chest radiographs (CXRs are performed routinely after permanent pacemaker implantation to identify pacemaker lead position and exclude pneumothorax. We assessed the clinical value and need for this procedure. Design: Retrospective analysis of pacemaker data and CXRs following permanent pacemaker insertion between December 2002 and February 2004. Materials and Methods: Post-procedural CXRs were available in 125/126 consecutive patients after either first endocardial pacemaker implantation or insertion of at least one new lead. Subclavian vein puncture was used for venous access in all cases. CXRs were examined to establish the incidence of pneumothorax and assess pacing lead positions. The clinical records were examined in all patients who had subsequent CXRs or a further pacemaker procedure to identify the indication for these and to establish whether CXR had influenced patient management. Results: In total, 192 post-procedural CXRs were performed, either postero-anterior (PA and/or lateral views. Ventricular and/or atrial pacing lead contour and electrode position was considered radiographically appropriate in 86% CXRs. Fourteen per cent of post-procedural radiographs were considered to have radiologically sub-optimal pacemaker lead positioning. None of the patients with these "abnormal" radiographs experienced subsequent pacemaker complications or had further radiographs recorded at a later date. Later repeat CXRs were performed in 16 patients (13% but only 3 patients (2% had pacing abnormalities as the primary indication. All three had satisfactory pacing lead position on initial post-implantation and later radiographs, but required further procedures for lead re-positioning. Iatrogenic pneumothorax occurred in one patient (incidence 0.8% in our series. CXR confirmed the clinical diagnosis and allowed an assessment of size to guide treatment. Conclusion: Routine CXR after permanent pacemaker insertion is not necessary in uncomplicated cases with adequate pacing characteristics.

  9. Permanent LDR implants in treatment of prostate cancer

    International Nuclear Information System (INIS)

    Low-dose rate brachytherapy (LDR-BT) is a radiation method known for several years in the treatment of localized prostate cancer. The main idea of this method is to implant small radioactive seeds directly into the prostate gland. LDR brachytherapy is applied as a monotherapy and also used along with external beam radiation therapy (EBRT) as a boost. In most cases it is used as a sole radical treatment modality, but not as a palliative treatment. The application of permanent seed implants is a curative treatment alternative in patients with organ- confined cancer, without extracapsular extension of the tumour. This technique is particularly popular in the United States. In Europe, however, high-dose rate brachytherapy (HDR-BT) is more popular in early-stage prostate cancer treatment (as a boost). The aim of this publication is to describe methods, indications, complications and selected results of prostate cancer LDR brachytherapy. (authors)

  10. Impact of pre-implant lower urinary tract symptoms on postoperative urinary morbidity after permanent prostate brachytherapy

    International Nuclear Information System (INIS)

    The objectives of this study was to assess the impact of baseline lower urinary tract symptoms on postoperative urinary morbidity in patients being treated for prostate cancer with 125-I permanent prostate brachytherapy. A total of 104 prostate cancer patients were enrolled in this study. Their urinary morbidity was followed up using the International Prostate Symptom Score and Expanded Prostate Cancer Index Composite for 12 months or more after permanent prostate brachytherapy. Patients were classified into two groups based on their baseline International Prostate Symptom Score: the low International Prostate Symptom Score group (score?7) and the high International Prostate Symptom Score group (score?8). Urinary morbidity was estimated in each group based on the results of the International Prostate Symptom Score and Expanded Prostate Cancer Index Composite measured before permanent prostate brachytherapy, and at 1, 3, 6, 9 and 12 months after the end of all radiation therapy. The overall mean total International Prostate Symptom Score, International Prostate Symptom Score quality of life score, and urinary-related scores for Expanded Prostate Cancer Index Composite were significantly worse at 1 month after the end of treatment, but they improved gradually after the treatment and recovered to the baseline level within 12 months. Even in the high-International Prostate Symptom Score group, the International Prostate Symptom Score and International Prostate Symptom Score Quality of Life score were significantly worse at 1-3 months after permanent prostate brachytherapy, and then recovered to the baseline level without prolongation. Although the urination-related Expanded Prostate Cancer Index Composite score in the high-International Prostate Symptom Score group was significantly worse at 1 month after permanent prostate brachytherapy in comparison with that in the low-International Prostate Symptom Score group, it recovered to the baseline level without prolongation. The present findings suggest that the presence of lower urinary tract symptoms before implantation does not prolong urinary morbidity after permanent prostate brachytherapy. (author)

  11. Role of TPS in 125I brachytherapy for orbital tumors

    International Nuclear Information System (INIS)

    Objective: To investigate the role of TPS in 125I brachytherapy for orbital tumors. Methods: Sixty-six patients with orbital tumor treated with 125I seeds from 2005 to 2009 were retrospectively analyzed. Forty-three patients were treated using TPS guided brachytherapy and the prescribed dose was 140 Gy. Other 23 patients were treated without TPS but simply implanted with 125I seeds at 1 cm intervals in parallel with each other intraoperatively. CT and TPS quality verification were performed postoperatively in all patients. Also, CT and (or) MRI examination were performed at 3, 6, 12 and 24 months after brachytherapy for follow-up. ?2 test and Kaplan-Meier survival analysis with log-rank significance test were used with SPSS 17.0. Results: A total of 1070 125I seeds were implanted in 66 cases, on average, (16.2 ± 7.3) seeds for each patient. The satisfaction rates of postoperative quality verification in patients with and without TPS pre-plans were 79.07% (34/43) and 43.48% (10/23) respectively (?2=8.542, P=0.003). Ten patients were lost in follow-up. Local recurrence rates in patients with favorable postoperative quality verification were 0 (0/37) in 3 months, 6.25% (2/32) in 6 months, 13.64% (3/22) in 12 months and 3/9 in 24 months respectively, which were significantly different from those (5.26% (1/19), 16.67% (3/18), 30.77% (4/13), 6/6) in the patients with inferior postoperative quality verification (?2=9.017, P=0.0003). Conclusions: TPS plays an important role in 125I brachytherapy for orbital tumors. Also, postoperative quality verification by TPS may help predict the local recurrence after brachytherapy. (authors)

  12. Urethral dose and increment of international prostate symptom score (IPSS) in transperineal permanent interstitial implant (TPI) of prostate cancer

    Energy Technology Data Exchange (ETDEWEB)

    Murakami, N.; Itami, J. [Dept. of Radiation Therapy and Oncology, International Medical Center of Japan, Tokyo (Japan); Div. of Radiation Therapy, National Cancer Center Hospital, Tokyo (Japan); Okuma, K.; Marino, H.; Ban, T.; Nakazato, M.; Kanai, K.; Naoi, K.; Fuse, M. [Dept. of Radiation Therapy and Oncology, International Medical Center of Japan, Tokyo (Japan); Nakagawa, K. [Dept. of Radiology, School of Medicine, Tokyo Univ. (Japan)

    2008-10-15

    Purpose: to find the factors which influence the acute increment of international prostate symptom score (IPSS) after transperineal permanent interstitial implant (TPI) using {sup 125}I seeds. Patients and methods: from April 2004 through September 2006, 104 patients with nonmetastatic prostate cancer underwent TPI without external-beam irradiation. Median patient age was 70 years with a median follow-up of 13.0 months. 73 patients (70%) received neoadjuvant hormone therapy. The increment of IPSS was defined as the difference between pre- and postimplant maximal IPSS. Clinical, treatment, and dosimetric parameters evaluated included age, initial prostate-specific antigen, Gleason Score, neoadjuvant hormone therapy, initial IPSS, post-TPI prostatic volume, number of implanted seeds, prostate V{sub 100}, V{sub 150}, D{sub 90}, urethral D{sub max}, and urethral D{sub 90}. In order to further evaluate detailed urethral doses, the base and apical urethra were defined and the dosimetric parameters were calculated. Results: the IPSS peaked 3 months after TPI and returned to baseline at 12-15 months. Multivariate analysis demonstrated a statistically significant correlation of post-TPI prostatic volume, number of implanted seeds, and the dosimetric parameters of the base urethra with IPSS increment. Conclusion: the base urethra appears to be susceptible to radiation and the increased dose to this region deteriorates IPSS. It remains unclear whether the base urethral dose relates to the incidence of late urinary morbidities. (orig.)

  13. Urethral dose and increment of international prostate symptom score (IPSS) in transperineal permanent interstitial implant (TPI) of prostate cancer

    International Nuclear Information System (INIS)

    Purpose: to find the factors which influence the acute increment of international prostate symptom score (IPSS) after transperineal permanent interstitial implant (TPI) using 125I seeds. Patients and methods: from April 2004 through September 2006, 104 patients with nonmetastatic prostate cancer underwent TPI without external-beam irradiation. Median patient age was 70 years with a median follow-up of 13.0 months. 73 patients (70%) received neoadjuvant hormone therapy. The increment of IPSS was defined as the difference between pre- and postimplant maximal IPSS. Clinical, treatment, and dosimetric parameters evaluated included age, initial prostate-specific antigen, Gleason Score, neoadjuvant hormone therapy, initial IPSS, post-TPI prostatic volume, number of implanted seeds, prostate V100, V150, D90, urethral Dmax, and urethral D90. In order to further evaluate detailed urethral doses, the base and apical urethra were defined and the dosimetric parameters were calculated. Results: the IPSS peaked 3 months after TPI and returned to baseline at 12-15 months. Multivariate analysis demonstrated a statistically significant correlation of post-TPI prostatic volume, number of implanted seeds, and the dosimetric parameters of the base urethra with IPSS increment. Conclusion: the base urethra appears to be susceptible to radiation and the increased dose to this region deteriorates IPSS. It remains unclear whether the base urethral dose relates to the incidence of late urinary morbidities. (orig.)

  14. Temporary and permanent inferior vena cava filter combination in a young patient: to implant or not to implant?

    Science.gov (United States)

    Kutlu, Ramazan; Alkan, Alpay; Sigirci, Ahmet; Altinok, Tayfun; Yildirim, Zeki

    2003-01-01

    The decision to implant vena cava filters, either temporary or permanent, is difficult in young patients. We present the case of a young man with pulmonary embolism in whom temporary and permanent inferior vena cava filters were implanted. The decision process is discussed in relation to the current literature. PMID:14753313

  15. Temporary and Permanent Inferior Vena Cava Filter Combination in a Young Patient: To Implant or Not to Implant?

    International Nuclear Information System (INIS)

    The decision to implant vena cava filters, either temporary or permanent, is difficult in young patients. We present the case of a young man with pulmonary embolism in whom temporary and permanent inferior vena cava filters were implanted. The decision process is discussed in relation to the current literature

  16. Rectal injury during permanent seed implantation for prostate brachytherapy

    International Nuclear Information System (INIS)

    Serious complications have not been previously reported during seed implantation for prostate brachytherapy. We present an unreported case of rectal injury caused by an ultrasound probe. A 67-year-old male presented with a serum prostate-specific antigen level of 5.50 ng/ml, a Gleason score of 7 (3+4) and clinical T2a adenocarcinoma of the prostate. A transperineal permanent prostate brachytherapy implantation was performed. The patient subsequently complained of abdominal pain postoperatively. A gastrointestinal perforation was suspected based on an abdominal X-ray obtained on the day after the brachytherapy. Rectal injury was recognized during an exploratory laparotomy, and a primary closure and temporary diversion ileostomy were performed. The healing of the injury was confirmed by colonoscopy and an ileostomy closure was performed 2 months after the temporary diversion. The investigating committee for this accident concluded that the ultrasound probe had perforated the rectum. This is the first case of a rectal injury during seed implantation for prostate brachytherapy. (author)

  17. Tumor therapy with 125I-octreotide and 125I-UdR

    International Nuclear Information System (INIS)

    Purpose: To determine the tumor cell damage effect with Auger-electron emitter 125I in different chemical states. Methods: (1) [Tyr3] octreotide (TOC) and UdR are labeled with 125I,respectively. (2) Receptor analysis of 125I-TOC on small cell lung cancer (SCLC) NCI-H446 cell lines is performed comparing with normal lymph cells. NCI-H446 cells added various dose of 125I-TOC are incubated for different time with 125I-Nal and non-labeled TOC as control. The capacity of NCI-H446 cell lines bound and internalization of 125I TOC are determined. The radiation damage of tumor cells is measured by MTF methods. (3) The killing effects of 125I-UdR in human pancreatic cancer cell line Bax-Pc and Sca-BER bladder carcinoma cells are evaluated with the similar methods. I-UdR penetrating into the Sca-BER cell nucleus is observed with confocal microscope. The grow suppression and clonogenic formation of Sca-BER cells after incubation with 125I-UdR are analyzed. Proliferation fraction and S phase cell fraction of Sca-BER cell added 125I-UdR is measured with flow cytometric analysis. Results: (1) Kd=(0.56?2.0) x 10-11 mol/L and Bmax=(1.17?2.0) x 105 cell site are obtained by receptor analysis of 125I-TOC on NCI-H446 cells. Comparatively, the difference between total binding and non-specific binding is low and there is no saturation of specific binding for normal lymphocyte. About 50% of 125I-TOC is internalized into the NCI-H446 cell nucleus at 24h after incubation. The damige of NCI-H446 cells by 125I-TOC is clearly observed. (2) The penetration amount of 125I-UdR into cell nucleus increases with the incubate time when the concentration of 125I-UdR is in the range of 10?500 kBq/mL and reaches the peak fraction of 94% at 36 h after incubation. The radioactivity of 125I-UdR is then achieved equelibration and no more increased with time. The linear correlation with ?=0.867?0.978 between the concentration of 125I-UdR in cell nucleus and the incubation time is observed before reaching peak value. As a control, very low radioactivities in cells and in neucleus are measured in Na 125I case. Incubating for 36 h, the amount of 125I-UdR entering into the cells and nucleus are 1000 times more than that with Na 125I. The 125I-UdR killing effect of 100 kBq to Bax-Pc cells is 60 times more than Na 125I after 36 h incubation. The Sca-BER bladder carcinoma cells growth cycle in the treatment group with 125I-UdR is suppressed and clonogenic formation is lower in experimental group than in control group. Proliferation fraction and S phase cell fraction decrease and apoptosis fraction increase with 125I-UdR treatment time. The results of confocal microscope shows the Sca-BER cells of treatment group at 48h after administration are entirely broken. Conclusion: 125I-TOC has a better specificity to the somatostatin positive tumors. 125I-UdR is a cell cycle dependent agent. It can be incorporated into DNA of Bax-Pc cells and can selectively kill tumor cells in S phase. Both 125I-TOC and 125I-UdR are more effective for killing tumor cells than Na 125I.

  18. Comparison of day 0 and day 14 dosimetry for permanent prostate implants using stranded seeds

    International Nuclear Information System (INIS)

    Purpose: To determine, using MRI-based dosimetry (Day 0 and Day 14), whether clinically significant changes in the dose to the prostate and critical adjacent structures occur between Day 0 and 14, and to determine to what degree any changes in dosimetry are due to swelling or its resolution. Methods and Materials: A total of 28 patients with a permanent prostate implant using 125I rapid strands were evaluated at Days 0 and 14 by CT/MRI fusion. The minimal dose received by 90% of the target volume (prostate D9), percentage of volume receiving 100% of prescribed minimal peripheral dose (prostate V10), external sphincter D9, and 4-cm3 rectal volume dose were calculated. An acceptable prostate D9 was defined as D9 >90% of prescription dose. Prostate volume changes were calculated and correlated with any dosimetry change. A paradoxic dosimetric result was defined as an improvement in D9, despite increased swelling; a decrease in D9, despite decreased swelling; or a large change in D9 (>30 Gy) in the absence of swelling. Results: The D9 changed in 27 of 28 patients between Days 0 and 14. No relationship was found between a change in prostate volume and the change in D9 (R2 = 0.01). A paradoxic dosimetric result was noted in 11 of 28 patients. The rectal dose increased in 23 of 28 patients, with a >30-Gy change in 6. The external sphincter D9 increased in 19 of 28, with a >50-Gy increase in 6. Conclusion: The dose to the prostate changed between Days 0 and 14 in most patients, resulting in a change in clinical status (acceptable or unacceptable) in 12 of 28 patients. Profound increases in normal tissue doses may make dose and toxicity correlations using Day 0 dosimetry difficult. No relationship was found between the prostate volume change and D9 change, and, in 11 patients, a paradoxic dosimetric result was noted. A differential z-axis shift of stranded seeds vs. prostate had a greater impact on final dosimetry and dose to critical adjacent tissues than did prostate swelling. These findings challenge the model that swelling is the principal cause of dosimetric changes after implantation. Stranded seeds may have contributed to this outcome. On the basis of these findings, a change in technique to avoid placement of stranded seeds inferior to the prostate apex has been adopted. These results may not apply to implants using single seeds within the prostate

  19. Preparation of 125I FSH hormone

    International Nuclear Information System (INIS)

    Labelling of human FSH of pituitary origin with 125I and its purification are described. Suitable parameters are selected for the use of radioimmunologic technique for FSH dosage in human serum. (author)

  20. Conformal prostate brachytherapy guided by realtime dynamic dose calculations using permanent 125iodine implants: technical description and preliminary experience

    Scientific Electronic Library Online (English)

    Pedro J., Prada; German, Juan; José, Fernández; González-Suárez, H; Álvaro, Martínez; José, González; Ana, Alonso.

    2006-11-01

    Full Text Available Objetivo: El tratamiento con braquiterapia de baja tasa de dosis (LDR) con implantes permanentes de 125-I o 103Pb, constituyen en la actualidad una opción terapéutica en los pacientes con cáncer de próstata de bajo riesgo. La variación observada en el posicionamiento espacial de la próstata, así com [...] o en el volumen y contorno prostático entre las imágenes obtenidas durante la planificación y posteriormente durante la intervención, hacen dudar de la exactitud de dosificación, en los pacientes tratados con la técnica de preplanificación. Analizamos la técnica basada en la planificación previa, la planificación intraoperatoria interactiva, así como nuestro proceder actual de planificación intraoperatoria por cálculo dinámico en tiempo real y los motivos que nos llevaron a realizar este cambio de técnica. Métodos: Con el cálculo del volumen prostático preoperatorio por ecografía transrectal, determinamos la posibilidad de realizar el implante en base a las consideraciones anatómicas existentes y decidimos la actividad por semilla y la actividad total del implante. El día de la intervención comprobamos de nuevo la volumetría, obtenemos de nuevo las imágenes ecográficas de base a apex, ayudados por un stepper motorizado que va conectado con el ecógrafo y el planificador. Cada aguja que se coloca en la posición que deseamos y no en una coordenada obligada, se identifica en el planificador en la posición real, una vez colocadas todas las agujas y obtenidas unas primeras isodosis adecuadas, realizamos una cistoscopia flexible y a continuación sembramos, identificando todas y cada una de las semillas en la retirada de la aguja guía ecográficamente, con lo que nos permite obtener una postplanificación intraoperatoria en tiempo real y hacer las correcciones oportunas en el propio acto quirúrgico. Realizamos un implante periférico puro. Resultados: Iniciamos los tratamientos con braquiterapia de baja tasa de dosis en 1.999. Superadas las 700 intervenciones, hemos evaluado a los primeros 63 pacientes tratados con la técnica de cálculo dinámico de dosis en tiempo real por presentar un seguimiento mínimo de 10 meses. El tiempo medio del proceso fue de 90 minutos. La media de seguimiento para los 63 pacientes estudiados fue 20 meses con un rango entre 10 y 36 meses. Un 55% de los pacientes fueron estadiados como T1c, 36% T2a y 9% T2b. En el 81% de los pacientes el Gleason fue Abstract in english Objetive: Low dose rate (LDR) prostate brachytherapy (permanent 125I or 103Pd seeds) is an accepted treatment option for low risk prostate cancer patients. However, differences in prostate spatial location, volume and gland deformation between the images obtained during pre-planning and later on dur [...] ing the implant procedure prevent the pre-planned intended dose to be accurately delivered. We are reporting on a new technique based on interactive real-time dynamic intra-operative dose calculation with avoidance of post-implant CT for final dosimetry. The reasons leading us to implementing this new technique are discussed and preliminary results reported. Methods: A pre-planning TRUS for volumetric analysis is performed in all our patients prior to implantation. This TRUS accomplishes two objectives: 1) assessment of implantability of the gland, of organs at risk and anatomical considerations and 2) determination of seed activity and total number of seeds. On the day of the implant, new TRUS images from base to apex are obtained using a motorized stepper connected to the ultrasound and planning system. Each real time needle position placed on the target is identified and capture by the planning system in the true position. Once all real needle positions have been captured, dosimetry is performed intra-operatively and the physician approves the corresponding isodoses on real time. Flexible cystoscopy is then performed followed by seed placement. Each seed implanted is then identified upon withdrawing the needle using TRUS guidance. This allows real-time intra-operative dosi

  1. 125I decay in synthetic oligodeoxynucleotides

    International Nuclear Information System (INIS)

    The availability of synthetic oligodeoxynucleotides provides the opportunity to study the effects of 125I in DNA with added precision and detail, compared to an earlier study (Martin and Haseltine, Science 214, 296, 1981). The authors have designed a template/primer system which enables incorporation of 125IdC into a defined location in a 31mer. The main advantage of this approach is that relatively large amounts (a few ?Ci) of DNA with both 32P and 125I can be produced quite easily. Consequently, when 125I-induced DNA damage is analyzed on DNA sequencing gels, the distribution of 32P-labeled cleavage products can be determined more accurately, following accumulation of decay events under various conditions (e.g. temperature, buffer components, free radical scavengers). The results of preliminary experiments suggest that the yield of DNA strand breaks per decay approaches one, at least for the 125I labeled strand. Extension of this experimental approach will also enable investigation of the nature of the terminii (e.g. phophoryl-versus phophorylglycollate) at either side of 125I decay-induced DNA strand breaks. The question of energy migration is also being investigated in the oligodeoxynucleotide system, by studying the effects of inclusion of BrUdR nucleotides at various distances from the 125IdC

  2. Dosimetry of 125I seed eye plaques

    International Nuclear Information System (INIS)

    The ability of a brachytherapy treatment-planning computer program to calculate accurately the dose from 125I seeds at distances relevant to eye plaque therapy was investigated. Thermoluminescent dosimetry measurements were made in a plastic phantom at depths of 0.5, 0.97, and 1.5 cm, and results were corrected for finite dosimeter size and phantom effects. Doses were calculated at the same depths with an 125I seed linear source model that accounted for dose anisotropy. Measurements and calculations were found to agree within their mutual uncertainties. The presence of a gold plaque was found to reduce the dose at all measured depths by 8%

  3. Treatment of recurrent gynecologic malignancies with iodine-125 permanent interstitial irradiation

    International Nuclear Information System (INIS)

    Purpose: To analyze the outcome of permanent 125I interstitial radiotherapy for unresectable retroperitoneal recurrences of gynecologic malignancies. Methods and Materials: A retrospective review of 20 patients treated between 1979 and 1993 was performed to evaluate survival and morbidity associated with the interstitial 125I technique. Results: Nineteen tumors were located on the lateral pelvic wall and one in the para-aortic region. Eight patients, not previously irradiated, received external beam radiotherapy (EBRT) along with 125I interstitial implants placed at the time of celiotomy. Nineteen (95%) are dead of disease at 1-69 months of follow-up. The median survival was 7.7 months for patients treated with 125I alone and 25.4 months for those treated with both 125I and EBRT. One patient is alive without evidence of disease 69 months after 125I implantation. Fistulas, bowel obstructions, and fatal complications occurred only among patients previously irradiated. Conclusions: When used in a previously irradiated field, 125I interstitial radiotherapy has major morbidity and is unlikely to be associated with cure or long-term survival. In radiotherapy-naive patients with unresectable isolated recurrent gynecologic malignancies, 125I implants and EBRT are feasible and occasionally may contribute to long-term disease-free survival

  4. Combined interstitial 125I and external X-irradiation on a rat rhabdomyosarcoma

    International Nuclear Information System (INIS)

    The effect of graded external radiation doses and a dose administered by an implanted 125I seed on growth delay and cure rate of a rat rhabdomyosarcoma was investigated. One 125I seed (0.40 or 0.50 mCi) was implanted per tumour when the tumours had grown to a predetermined size. The irradiation by the 125I seed did not cause significant tumour growth delay. When implantation of an 125I seed was combined with graded external radiation doses, the growth delay observed after these combined regimens was significantly greater than that observed after treatment with external doses alone. The same was observed for tumour cure rates. The effectiveness of the 125I seed could be assessed as being equivalent to a single dose of external radiation of about 6-20 Gy, depending on the external dose applied. The application of 125I seeds combined with external irradiation to obtain local control might be recommended in those cases where the total dose of external radiation alone is limited by normal tissue reactions. 22 refs.; 6 figs

  5. Quality indicators for permanent I-125 prostate seed implants : seven years post implant dosimetry evaluation

    International Nuclear Information System (INIS)

    Full text: The aim of the current work is to assess the progress of prostate implant quality via post implant dosimetry over a 7-year time period. The roles of post implant dosimetry (PID) after permanent 1-125 implant are to: identify suboptimal implants; assess the dosimetric quality indicators and evaluate dose to organs at risk. The 7-years PID learning-curve shows clear changes in dosimetric trend. Beside the expected improvement in technique the following factors were investigated: the replacement of the computed tomography (CT)-delineation based PID with ultrasound (US)-CT fusion based, and the evolution and influence of parameters such as 090 and V I 00. The correlation between dosimetric parameters and clinical outcome was also evaluated. Results A study on 30 patients showed manual target contouring on CT tends to overestimate the prostate volume when compared to ultrasound data (mean difference 38.3%), translating to CT based D90 values being lower than US-CT D90 by an average of 6%. There was 4.7% patient relapse and urinary retention was reported in 2.7% of the patients. CT-based PID was found less reliable than US-CT fusion due to target overestimation. This result shows the biased interpretation of low D90 based on CT targeting and may not relate to patient relapse data. The low urinary retention statistics are in accordance with the PID data for the organ, as only 5.2% of patients had their PID D I 0 >218 Gy, i.e. above recommended GEC-ESTRO guidelines. Besides the 'learning' component, the 7-years PID D90 curve is influenced by PID technique.

  6. Reactions of 125I activated by 125Xe(EC)125I process with methane

    International Nuclear Information System (INIS)

    The reactions of 125I obtained from the 125Xe(EC)125I process with methane have been investigated. It was confirmed that electron scavengers, such as I2, SF6, and O2, play an important role. The main product is only CH3125I, the yield decreasing significantly with the concentration of Xe. By adding various additives, the yield of CH3125I in the presence of trace amount of I2 was assigned as follows: 8.7+-6.7% by the hot atom reaction, 35.8+-8.0% by 125I+ in the 1D2 state, and 31.5+-2.0% by 125I+ in the 3P states. The results are discussed in comparison with those reported on similar reactions utilizing different activation processes. Chemical sequences of the formation of CH3125I are proposed. (auth.)

  7. Preparation of 125I labelled compound

    International Nuclear Information System (INIS)

    Iodinated compounds with 131I, 125I and 123I have been widely used for biochemical function studies. In conjunction with SPECT, [123I] labelled proteins have various diagnostic and therapeutic applications in nuclear medicine. In this study, synthesis and quality control of [18F]radiofluorinated and radioiodinated of some proteins and peptides as well as their biological behaviors are considered to be investigated. (author)

  8. 125I and 125I-glucagon metabolism in rat liver

    International Nuclear Information System (INIS)

    This report suggests that the time course and enzymatic nature of 125I-insulin degradation in vivo correlates with major subcellular locations of autoradiographic grains during the course of endocytosis. 125I-insulin and hormone fragments were detected in liver extracts using reverse-phase high performance liquid chromatography (RP-HPLC). 125I-insulin was rapidly degraded in vivo. Comparison with autoradiographic studies suggests insulin degradation begins before substantial lysosomal localization is observed. Studies using an isolated perfused rat liver system suggest that the plasmalemma does not mediate rapid insulin degradation as observed in vivo. The author, therefore, sought to identify 125I-insulin fragments which typified the activities of the most-implicated intracellular degradative systems: acidic lysosomal proteolysis, a microsomal reductive system such as glutathione-insulin transhydrogenase (GIT), and a cytosolic neutral proteolytic system such as insulin protease. Significant GIT activity was not observed in vivo nor in vitro with liver homogenates. Purified liver insulin protease degraded 125I-insulin in a fashion similar to that observed in vivo. Lysosomal activity was observed only after a lag of approximately 10 minutes. Complete degradation of 125I-glucagon in vivo occurred within 1 minute of hormone injection

  9. Continuous and low-energy 125I seed irradiation changes DNA methyltransferases expression patterns and inhibits pancreatic cancer tumor growth

    Directory of Open Access Journals (Sweden)

    Gong Yan-fang

    2011-04-01

    Full Text Available Abstract Background Iodine 125 (125I seed irradiation is an effective treatment for unresectable pancreatic cancers. However, the radiobiological mechanisms underlying brachytherapy remain unclear. Therefore, we investigated the influence of continuous and low-energy 125I irradiation on apoptosis, expression of DNA methyltransferases (DNMTs and cell growth in pancreatic cancers. Materials and methods For in vitro 125I seed irradiation, SW-1990 cells were divided into three groups: control (0 Gy, 2 Gy, and 4 Gy. To create an animal model of pancreatic cancer, the SW 1990 cells were surgically implanted into the mouse pancreas. At 10 d post-implantation, the 30 mice with pancreatic cancer underwent 125I seed implantation and were separated into three groups: 0 Gy, 2 Gy, and 4 Gy group. At 48 or 72 h after irradiation, apoptosis was detected by flow cytometry; changes in DNMTs mRNA and protein expression were assessed by real-time PCR and western blotting analysis, respectively. At 28 d after 125I seed implantation, in vivo apoptosis was evaluated with TUNEL staining, while DNMTs protein expression was detected with immunohistochemical staining. The tumor volume was measured 0 and 28 d after 125I seed implantation. Results 125I seed irradiation induced significant apoptosis, especially at 4 Gy. DNMT1 and DNMT3b mRNA and protein expression were substantially higher in the 2 Gy group than in the control group. Conversely, the 4 Gy cell group exhibited significantly decreased DNMT3b mRNA and protein expression relative to the control group. There were substantially more TUNEL positive in the 125I seed implantation treatment group than in the control group, especially at 4 Gy. The 4 Gy seed implantation group showed weaker staining for DNMT1 and DNMT3b protein relative to the control group. Consequently, 125I seed implantation inhibited cancer growth and reduced cancer volume. Conclusion 125I seed implantation kills pancreatic cancer cells, especially at 4 Gy. 125I-induced apoptosis and changes in DNMT1 and DNMT3b expression suggest potential mechanisms underlying effective brachytherapy.

  10. Moving Toward Focal Therapy in Prostate Cancer: Dual-Isotope Permanent Seed Implants as a Possible Solution

    International Nuclear Information System (INIS)

    Purpose: To compare the ability of single- and dual-isotope prostate seed implants to escalate biologically effective dose (BED) to foci of disease while reducing prescription dose to the prostate. Methods and Materials: Nine plans, using 125I, 103Pd, and 131Cs alone and in combination were created retrospectively for 2 patients. Ultrasound and MRI/MRS datasets were used for treatment planning. Voxel-by-voxel BED was calculated for single- and dual-isotope plans. Equivalent uniform BED (EUBED) was used to compare plans. The MRS-positive planning target volumes (PTVi) were delineated along with PTV (prostate + 5 mm), rectum, and urethra. Single-isotope implants, prescribed to conventional doses, were generated to achieve good PTV coverage. The PTVi were prospectively used to generate implants using mixtures of isotopes. For mixed-radioisotope implants, we also explored the impact on EUBED of lowering prescription doses by 15%. Results: The EUBED of PTVi in the setting of primary 125I implant increased 20-66% when 103Pd and 131Cs were used compared with 125I boost. Decreasing prescription dose by 15% in mixed-isotope implants results in a potential 10% reduction in urethral EUBED with preservation of PTV coverage while still boosting PTVi (up to 80%). When radiobiologic parameters corresponding to more-aggressive disease are assigned to foci, faster-decaying isotopes used in mixed implants have the potential to preserve the equivalent biological effect of mono-isotope implants considering less-aggressive disease distributed in the entire prostate. Conclusions: This is a hypothesis-generating study proposing a treatment paradigm that could be the middle ground between whole-gland irradiation and focal-only treatment. The use of two isotopes concurrent with decreasing the minimal peripheral dose is shown to increase EUBED of selected subvolumes while preserving the therapeutic effect at the level of the gland.

  11. Studies on 125I contamination to various crops

    International Nuclear Information System (INIS)

    The contamination of 125I to various crops such as corn, wheat, barley, soybean, pea, and rice etc. was studied. The results showed that under the same conditions the degree of 125I contamination varied with different kind of crops and materials used. 125I absorbed by the leaves could be transferred into newly grown leaves, pods and roots. 125I on the surface of stems could be horizontally transferred into internal tissue. 125I on the soil surface was also able to transfer to the deep layer of soil

  12. Psychosocial aspects and mental health in children after permanent pacemaker implantation

    DEFF Research Database (Denmark)

    Andersen, C; Hørder, K; Kristensen, L; Mickley, H

    1994-01-01

    The present study was designed to evaluate the psychosocial status and the mental health of children receiving a permanent pacemaker during childhood. Nineteen children under the age of 19 years had a permanent pacemaker implanted. Contact was established to 15 of these patients, 7 girls and 8 boys, and they were given a child-psychiatric evaluation consisting of a semi-structured and a child-psychiatric interview. The psychological interview used intelligence tests and the Draw-A-Person test as...

  13. Interstitial implantation with radioisotopes

    International Nuclear Information System (INIS)

    This classic paper published in 1956, clearly demonstrated that higher doses could be delivered to the tumor by interstitial implant with better sparing of the surrounding normal tissues than with any other method of radiation therapy. The author discussed both temporary and permanent implant techniques, specifically using /sup 60/Co and /sup 198/Au. He discussed the superiority of /sup 60/Co with only two gamma photons of 1170 kev and 1330 kev and beta energy of 310 kev compared with a complex gamma spectrum as well as several beta spectra of various energies emitted by radium. This method is still used today in permanent implants for various sites. He initially used /sup 198/Au, /sup 222/Rn, and /sup 192/Ir but later recommended /sup 125/I seeds to be most suitable for permanent implants

  14. Local relapses after prostatic curie-therapy by permanent implants: radio-resistant prostate cancers or bad quality implant

    International Nuclear Information System (INIS)

    The assessment of the quality of a permanent implant of grains for a prostate cancer treatment is based on the dosimetric plan performed before the grain implantation or shortly after. The authors report a study of the correlation between 'under-dosed' areas assessed at the time of relapse, and intra-prostatic relapse sites. The study is based on 24 cases of proved intra-prostatic relapse. The prostatic volume has been divided into 12 areas, and three types of under-dosing have been defined. Parameters are the dose received by 90 per cent of the volume, and the volume receiving 100 per cent of the dose. A correlation appears between positive biopsies and 'under-dosing'. This corresponds to a bad quality implantation of grains for patients in a situation of prostatic relapse after implantation. Short communication

  15. Effectiveness of Permanent Implantable Catheter (Polysite in Children with Cancer

    Directory of Open Access Journals (Sweden)

    Hashemizadeh Hayede

    2012-03-01

    Full Text Available AbstractBackground Totally implantable central venous access devices (ports have been available for over 10 years, but have not been achieved widespread use in pediatric oncology patients. Ports facilitate the administration of chemotherapy in children with cancer. Materials and Methods In this study, we investigated early complications of implantable central venous access devices in children who suffered from different type of cancer. All of the complications were recorded by staff nurses by checklist for one week. This study included 68 patients with different cancer (lymphoma-leukemia-sarcoma and wilms’ tumor who were treated between April 2007 and November 2011 in oncology department of Dr Sheikh hospital, Mashhad University of medical science. ResultsVenous ports were placed in 26 (38.2% girls and 42 (61.8% boys aged between 2 and 12 years (mean: 6 years.We implanted all of the venous ports in patients for chemotherapy, and port implantation procedures were performed by one experienced Pediatric Surgery. 3 cases (4.4% have needle access site infections which were controlled with starting of antibiotics. Catheter leakage in 3 cases (4.4%, port-catheter disconnection in 4(5.8% cases, Occlusion of the system in 5 cases (7.4%. In this period, there were no major complications.Conclusion With proper placement technique and adequate nursing care, they represent a definite improvement in child cancer therapy. Ports can provide satisfactory for the majority of pediatric oncology patients, with a low risk of line-related complications and a high degree of acceptability to children and their parents.

  16. 78 FR 41125 - Interim Enforcement Policy for Permanent Implant Brachytherapy Medical Event Reporting

    Science.gov (United States)

    2013-07-09

    ... Register on August 6, 2008 (73 FR 45635). The vast majority of commenters offered no objection to... the interim policy that the NRC will use for medical event reporting violations under current 10 CFR... COMMISSION Interim Enforcement Policy for Permanent Implant Brachytherapy Medical Event Reporting...

  17. Absorption of 125I and 3H in aquatic plants

    International Nuclear Information System (INIS)

    The absorption of 125I and 3H in four aquatic plants was studied by solution cultivation. The results showed that arrowhead (Sagittaria pygmaea Miq.) was the fastest in absorbing 125I among the four tested aquatic plants and its concentration factor for 125I was the highest (85.79). The alligator alternanthera (Alternanthera philoxeroides) was the slowest in absorbing 125I and its concentration factor was the lowest. However, the absorption of 3H in alligator alternanthera was the fastest among the four aquatic plants. After being absorbed by aquatic plants, the 125I could be transferred to the shoot. In arrowhead, about 75% of 125I remained in the root, 25% being transferred to the shoot

  18. Metabolism in the isolated rat heart: comparison of 125I-BMIPP with 125I-IPPA

    International Nuclear Information System (INIS)

    Objective: The fatty acid metabolism in myocardium is recently one of the most interesting subjects in nuclear cardiology. The purpose of this study was to clarify the metabolic fate of 125I-labeled 15-(p-iodophenyl)-3-(R, S)-methyl-pentadecanoic acid (125I-BMIPP) and 15-(p-[125I] iodophenyl) pentadecanoic acid (125I-IPPA) by means of isolated rat hearts. Methods: Ten isolated rat hearts were prepared and perfused with 125I-BMIPP (5 rats) or 125I-IPPA (5 rats) for 3 h following a basic perfusion of 30 min. After perfusion, the radioactivity in the recirculated buffer was measured. The metabolites in the buffer were then extracted and analyzed using high performance liquid chromatography (HPLC) and thin-layer chromatography (TLC). Results: At the beginning (5 rain) of 125I-BMIPP perfusion, the main radioactive peak appeared on HPLC at 37 min, which remained after 3 h perfusion. Several small peaks eluting were found before the parent peak at 30, 26, 21, 16, 12 and 9 min, respectively. At the beginning (5 min) of 125I-IPPA perfusion, the main peak appeared on HPLC at 33 min, which disappeared after 3 h. Conclusions: 125I-BMIPP strongly inhibited beta-oxidation, therefore appeared suitable for myocardial metabolic imaging. 125I-IPPA was metabolized rapidly. (authors)

  19. Pharmacokinetics of 125I-hirudin in rats and dogs

    International Nuclear Information System (INIS)

    Hirudin was 125I-labelled using a modified chloramine-T method. 125I-hirudin proved to be a suitable marker in pharmacokinetic studies, if unchanged 125I-hirudin in body fluids was determined by means of a binding assay using immobilized thrombin. In rats and dogs a study was performed on the pharmacokinetic behaviour of hirudin following intravenous and subcutaneous injection, resp., or one-hour infusion and pharmacokinetic parameters were calculated. (author)

  20. The contamination on farm products from 125I

    International Nuclear Information System (INIS)

    The 125I contamination on 15 farm products have been investigated. The effects of 12 farm crops (wheat, bean, eggplants and other vegetables) contaminated by 125I during the growing stage on their fruits and seeds have been studied. The results show that the 125I radioactive substance is mainly concentrated on the fruit surface, and the radioactivity rapidly decreased towards its kernel. The fruits and seeds would not be contaminated when plants were contaminated in the seedling stage

  1. Computational Program of Isodose and TPS of 125I Seed for Brachytherapy

    International Nuclear Information System (INIS)

    Radioactive sources are widely used in several fields including for medical purposes. One use of radioactive sources in medical field is radiotherapy to cure the cancerous organs. Brachytherapy term is the radiotherapy where the radiation source is placed inside or as close as possible to the cancer needing treatment. In order to support the domestic application of 125I seeds in brachytherapy, a computational program for isodose and TPS (Treatment Planning System) calculation shall be available. The preparation of the such program has been successfully developed using Microsoft Visual Basic for Windows and its supporting tools. This program can display the two-dimensions-isodose contour of 1-20 125I seeds presented in direction of lateral, anterior (AP) and caodal. The dose rate at the distances of 1, 2, 3 and 4 cm from the center point assumed as (0,0) can also be calculated from 1 to 360 days after implantation of the 125I seeds. The entered data as well as the resulting calculation and the contour presentation can be saved and be quickly traced and redisplayed at any time necessarily. This computer program is hopefully able to assist physicians in the implementation of 125I seeds implantation for brachytherapy. (author)

  2. Calculation of the dose equivalent around a patient receiving treatment with {sup 125}I seeds

    Energy Technology Data Exchange (ETDEWEB)

    Sasaki, Toru; Dokiya, Takushi; Toya, Kazuhito; Kawase, Takatsugu [National Tokyo Medical Center Hospital (Japan); Hashimoto, Mitsuyasu

    2001-03-01

    Interstitial brachytherapy with {sup 125}I seeds for treatment of prostate cancer is being carried out successfully in Europe and U.S.A. However, its widespread use in Japan has been limited by regulations governing the exposure of individuals. Basic radiation protection data are required to promote the use of {sup 125}I seed sources. In preparation for implementing this new modality, we carried out a series of measurements to determine the 1 cm dose equivalent in a caregiver located 1 m from the implanted patient. These measurements were compared with published recommendations of acceptable doses, and may be used to develop guidelines for discharge of the patient. The 1 cm dose equivalent was measured 1 m from the source under clinically relevant conditions by placing 50 {sup 125}I seeds (437.5 MBq) into the portion of a humanoid phantom that corresponds to the prostate. The 1 cm dose equivalent was 0.0014 {mu}Sv{center_dot}m{sup 2}{center_dot}MBq{sup -1}{center_dot}h{sup -1} 1 m from the surface of the phantom. The calculated dose to a caregiver based on this figure is well below the 5 mSv value recommended by the IAEA as a constraint dose for the caregiver. These measurements and calculations suggest that {sup 125}I seed implants of outpatients should be permissible. (author)

  3. Calculation of the dose equivalent around a patient receiving treatment with 125I seeds

    International Nuclear Information System (INIS)

    Interstitial brachytherapy with 125I seeds for treatment of prostate cancer is being carried out successfully in Europe and U.S.A. However, its widespread use in Japan has been limited by regulations governing the exposure of individuals. Basic radiation protection data are required to promote the use of 125I seed sources. In preparation for implementing this new modality, we carried out a series of measurements to determine the 1 cm dose equivalent in a caregiver located 1 m from the implanted patient. These measurements were compared with published recommendations of acceptable doses, and may be used to develop guidelines for discharge of the patient. The 1 cm dose equivalent was measured 1 m from the source under clinically relevant conditions by placing 50 125I seeds (437.5 MBq) into the portion of a humanoid phantom that corresponds to the prostate. The 1 cm dose equivalent was 0.0014 ?Sv·m2·MBq-1·h-1 1 m from the surface of the phantom. The calculated dose to a caregiver based on this figure is well below the 5 mSv value recommended by the IAEA as a constraint dose for the caregiver. These measurements and calculations suggest that 125I seed implants of outpatients should be permissible. (author)

  4. Synthesis and binding of [125I2]philanthotoxin-343, [125I2]philanthotoxin-343-lysine, and [125I2]philanthotoxin-343-arginine to rat brain membranes

    International Nuclear Information System (INIS)

    125I2-iodinated philanthotoxin-343 (PhTX-343), [125I2]PhTX-343-arginine, and [125I2]PhTX-343-lysine were synthesized and evaluated as probes for glutamate receptors in rat brain synaptic membranes. It was found that these probes were not specific for the glutamate receptors but may be useful for investigating the polyamine binding site. Filtration assays with Whatman GF/B fiber glass filters were unsuitable because the iodinated PhTX-343 analogues exhibited high nonspecific binding to the filters, thus hindering detection of specific binding to membranes. When binding was measured by a centrifugal assay, [125I2]PhTX-343-lysine bound with low affinity (KD = 11.4 ± 2 microM) to a large number of sites (37.2 ± 9.1 nmol/mg of protein). The binding of [125I2]PhTX-343-lysine was sensitive only to the polyamines spermine and spermidine, which displaced [125I2]PhTX-343-lysine with Ki values of (3.77 ± 1.4) x 10(-5) M and (7.51 ± 0.77) x 10(-5) M, respectively. The binding was insensitive to glutamate receptor agonists and antagonists. Binding results with [125I2]PhTX-343-arginine were similar to those of [125I2]-PhTX-343-lysine. Considering the high number of toxin binding sites (10000-fold more than glutamate) in these membranes and the insensitivity of the binding to almost all drugs that bind to glutamate receptors, it is evident that most of the binding observed is not to glutamate receptors. On the other hand, PhTX analogues with photoaffinity labels may be useful in the isolation/purification of various glutamate and nicotinic acetylcholine receptors; they could also be useful in structural studies of receptors and their binding sites

  5. Impact of differences in ultrasound and computed tomography volumes on treatment planning of permanent prostate implants

    International Nuclear Information System (INIS)

    Purpose: Both ultrasound (US) and computerized tomography (CT) images have been used in the planning of prostate interstitial therapy. Ultrasound images more clearly define the apex and capsule of the prostate, while CT images define seed positions for postimplant dosimetry. Proper registration of the US volume with the CT volume is critical to the assessment of dosimetry. We therefore compared US and CT prostate volumes to determine if differences were significant. Methods and Materials: Ten consecutive patients entered in an interstitial implant program were studied by pretreatment US. In addition, pretreatment CT scans were obtained and three physicians independently outlined the dimensions of the prostate on these images. The patients subsequently underwent placement of radioactive 125I or 103Pd. Postimplant CT images were obtained the next day and the postimplant prostate volumes were outlined by the same three physicians. Seven of 10 patients underwent late CT scans 9-14 months postimplant for comparison of preimplant and immediate postimplant CT studies. Results: There were differences between US and CT volumes. Although the physician-to-physician variation was significant, the trends were consistent, with US prostate volume typically smaller (47%) than the preimplant CT volume and markedly smaller (120%) than the postimplant CT volume. Prostate volumes derived from late CT images did not consistently return to preimplant levels. Conclusions: Significant differences in volume of the prostate structure were found between US and CT images. The data suggests that: (a) Implants planned on CT tend to overestimate the size of the prostate and may lead to unnecessary implantation of the urogenital diaphragm and penile urethra. (b) Registration of initial US and postimplant CT prostate volumes required for accurate dosimetry is difficult due to the increased volume of prostate secondary to trauma. (c) Further study to determine the optimal time for the postimplant CT is necessary

  6. Poster — Thur Eve — 41: Considerations for Patients with Permanently Implant Radioactive Sources Requiring Unrelated Surgery

    Energy Technology Data Exchange (ETDEWEB)

    Basran, P. S; Beckham, WA [Dept. Medical Physics, BC Cancer Agency- Vancouver Island Centre and Dept. Physics and Astronomy, University of Victoria, BC (Canada); Baxter, P [Vancouver Island Health Authority, Victoria, BC (Canada)

    2014-08-15

    Permanent implant of sealed radioactive sources is an effective technique for treating cancer. Typically, the radioactive sources are implanted in and near the disease, depositing dose locally over several months. There may be instances where these patients must undergo unrelated surgical procedures when the radioactive material remains active enough to pose risks. This work explores these risks, discusses strategies to mitigate those risks, and describes a case study for a permanent I-125 prostate brachytherapy implant patient who developed colo-rectal cancer and required surgery 6 months after brachytherapy. The first consideration is identifying the risk from unwarranted radiation to the patient and staff before, during, and after the surgical procedure. The second is identifying the risk the surgical procedure may have on the efficacy of the brachytherapy implant. Finally, there are considerations for controlling for radioactive substances from a regulatory perspective. After these risks are defined, strategies to mitigate those risks are considered. These strategies may include applying the concepts of ALARA, the use of protective equipment and developing a best practice strategy with the operating room team. We summarize this experience with some guidelines: If the surgical procedure is near (ex: 5 cm) of the implant; and, the surgical intervention may dislodge radioisotopes enough to compromise treatment or introduces radiation safety risks; and, the radioisotope has not sufficiently decayed to background levels; and, the surgery cannot be postponed, then a detailed analysis of risk is advised.

  7. Poster — Thur Eve — 41: Considerations for Patients with Permanently Implant Radioactive Sources Requiring Unrelated Surgery

    International Nuclear Information System (INIS)

    Permanent implant of sealed radioactive sources is an effective technique for treating cancer. Typically, the radioactive sources are implanted in and near the disease, depositing dose locally over several months. There may be instances where these patients must undergo unrelated surgical procedures when the radioactive material remains active enough to pose risks. This work explores these risks, discusses strategies to mitigate those risks, and describes a case study for a permanent I-125 prostate brachytherapy implant patient who developed colo-rectal cancer and required surgery 6 months after brachytherapy. The first consideration is identifying the risk from unwarranted radiation to the patient and staff before, during, and after the surgical procedure. The second is identifying the risk the surgical procedure may have on the efficacy of the brachytherapy implant. Finally, there are considerations for controlling for radioactive substances from a regulatory perspective. After these risks are defined, strategies to mitigate those risks are considered. These strategies may include applying the concepts of ALARA, the use of protective equipment and developing a best practice strategy with the operating room team. We summarize this experience with some guidelines: If the surgical procedure is near (ex: 5 cm) of the implant; and, the surgical intervention may dislodge radioisotopes enough to compromise treatment or introduces radiation safety risks; and, the radioisotope has not sufficiently decayed to background levels; and, the surgery cannot be postponed, then a detailed analysis of risk is advised

  8. Quality asurance of iodinated (125 I) human fibrinogen

    International Nuclear Information System (INIS)

    The radiopharmaceutical iodinated (125 I) human fibrinogen is currently used for the detection of deep vein thrombosis in the legs, a fairly common post-surgical complication. A comprehensive quality assurance programme for (125 I) - human fibrinogen has been determined for routine use at the Australian Radiation Laboratory, with adaptions necessary for hospital quality control testing

  9. Preoperative CT analysis of the mandible and maxilla for permanent dental prosthetic implantation

    International Nuclear Information System (INIS)

    The Branemark technique for permanently implanting dental prostheses is becoming universally accepted. The surgeon requires detailed knowledge of the cross-sectional anatomy of the alveolar ridges and inferior alveolar nerve for safe placement of the titanium fixtures. Axial CT scans of the mandible and maxilla, with oblique and panoramic CT reformations, were obtained in more than 100 patients. This report describes the anatomic variations in the maxilla and mandible as they relate to dental implantation surgery. The authors demonstrate the utility of this technique in preoperative surgical planning and postoperative evaluation

  10. Monitoring of 125I in saliva of workers internally contaminated with 125I

    International Nuclear Information System (INIS)

    Monitoring of workers who did iodination of protein was performed for 5 months on 10 persons. The activity in saliva was evaluated following the sum peak method by using a NaI(Tl) detector and a 400-channel analyzer. The concentration of 125I in saliva ranged 4.65 +- 2.1cBq (1.26 +- 0.57 pCi)/ml to 135 +- 2.7 cBq (36.45 +- 0.73 pCi)/ml and the average was 20.8 +- 1.9cBq (5.62 +- 0.51pCi)/ml. The ratio of concentration in saliva to used activity ranged (2.2 +- 0.64) x 10-9 to (3.6 +- 0.073) x 10-8 and the average was (8.1 +- 1.1) x 10-9. The thyroidal uptake per iodination ranged 146 Bq (3.94nCi) to 2700 Bq (72.9nCi). The ratio of the uptake to the used activity ranged from 7.3 x 10-5 to 5.4 x 10-6. The thyroidal absorbed dose ranged from 378 ?Gy (37.8 mrad) to 4740 ?Gy (474mrad). Monitoring of 125I in saliva was proved to be a useful method to investigate the internal contamination of workers doing iodination. (author)

  11. Safety handling of 125I in animal experiments

    International Nuclear Information System (INIS)

    Isotope 125I in animal experiments is used for several purposes. One major problem with using 125I is to handle it extremely carefully. The careful handling is required when using 125I in animal experiments because of its higher evaporation and difficulty for sealing. When conducting animal experiments white using 125I, we have encountered several serious problems but have devised new techniques and methods for a long time. In this paper, we will describe the safety handling for requirements based on our experiments. The newly devised safety handling procedures are the following: a device for protecting isotope contamination during the preparation of the injectable solution, collection method of airborne radioactivity from the animals that were injected, enhancing the method for autoradiography of the whole body, finding of elusion of 125I from the tissues during fixative process, estimation of the exposed time for light microscopic autoradiography. (author)

  12. Cytotoxicity of 125I decay produced lesions in chromatin

    International Nuclear Information System (INIS)

    In the authors' model of DNA damage produced by 125I, the M-XY Auger electron energy range corresponds with the diameter of a solenoid fiber in chromatin structure. Cell survival studies confirm the cytotoxicity of 125I decay especially when 125I is randomly incorporated into the nuclear genome (D0=96 decays/cell) and not in other subcellular organelles (e.g. mitochondrial DNA). Within the nucleus, cytotoxicity is increased three fold when only 5% of the nuclear genome is labelled with 125I (D0=30 decays/cell). Incorporation of 125I into only 5% of the genome was achieved by labelling cells in the presence of aphidicolin. The mechanism of the increased radiosensitivity is not due to a predisposed state in the cells to altered DNA damage or repair as measured by alkaline filter elution nor to selective irradiation of replication forks. (author)

  13. Evaluation of permanent I-125 prostate implants using radiographs and MRI

    International Nuclear Information System (INIS)

    Introduction: Localized prostatic cancer is managed by radical prostatectomy, external beam irradiation or a permanent implant with I-125 seeds. Permanent implants are indicated for small tumours (T1-T2) with a well to moderate histological differentiation. The technique used is a transrectal ultrasound guided transperineal implantation technique, which aims for a seed and dose distribution such that the initial doserate line of 7.8 cGy/h encompasses the prostate resulting in an accumulated dose of 160 Gy. Up till now the seed and dose distribution is evaluated from isocentric radiographs, which do not show the relation with the prostate. Objectives: The aim of this study is the development of a technique to reconstruct and evaluate the seed and dose distribution within the prostate. Methods: Twenty patients underwent radiography on the simulator and scanning on a whole body NMR system within 3 days after implantation of the I-125 seeds. Isocentric radiographs were used for reconstruction of the seed distribution, after which registration with the MR images provided the seed positions in relation to the prostate. Volume dose histograms were used to evaluate the implants. Results: The I-125 seeds and the prostate anatomy were well depicted on T1-weighted spin echo images with minimal read out gradient strength. To date, ten implants were evaluated. According to our method, the prostate volumes receiving the prescribed dose of 160 Gy ranged from 30 to 70% of the total prostate volumes. Conclusion: The combination of isocentric radiographs and MRI enables reconstruction of the seed and dose distribution in relation to the prostate and the computation of dose volume histograms, which may be of value in the evaluation of implant quality

  14. Apical Ballooning Syndrome (Takotsubo Cardiomyopathy) after Permanent Dual-Chamber Pacemaker Implantation

    OpenAIRE

    Armando Gardini; Francesco Fracassi; Emiliano Boldi; Remo Albiero

    2012-01-01

    Apical ballooning syndrome, also called takotsubo cardiomyopathy, has been recently reported. It may mimic acute myocardial infarction and is typically observed in postmenopausal women after stressful events. A 75-year-old female after permanent dual chamber pacemaker implant complained of chest pain with repolarization alterations suggesting acute myocardial ischemia. Echocardiography showed a left ventricle with akinesia of the apical portions and reduced global systolic function. The patie...

  15. Metallic artifact mitigation and organ-constrained tissue assignment for Monte Carlo calculations of permanent implant lung brachytherapy

    Energy Technology Data Exchange (ETDEWEB)

    Sutherland, J. G. H.; Miksys, N.; Thomson, R. M., E-mail: rthomson@physics.carleton.ca [Carleton Laboratory for Radiotherapy Physics, Department of Physics, Carleton University, Ottawa, Ontario K1S 5B6 (Canada); Furutani, K. M. [Department of Radiation Oncology, Mayo Clinic College of Medicine, Rochester, Minnesota 55905 (United States)

    2014-01-15

    Purpose: To investigate methods of generating accurate patient-specific computational phantoms for the Monte Carlo calculation of lung brachytherapy patient dose distributions. Methods: Four metallic artifact mitigation methods are applied to six lung brachytherapy patient computed tomography (CT) images: simple threshold replacement (STR) identifies high CT values in the vicinity of the seeds and replaces them with estimated true values; fan beam virtual sinogram replaces artifact-affected values in a virtual sinogram and performs a filtered back-projection to generate a corrected image; 3D median filter replaces voxel values that differ from the median value in a region of interest surrounding the voxel and then applies a second filter to reduce noise; and a combination of fan beam virtual sinogram and STR. Computational phantoms are generated from artifact-corrected and uncorrected images using several tissue assignment schemes: both lung-contour constrained and unconstrained global schemes are considered. Voxel mass densities are assigned based on voxel CT number or using the nominal tissue mass densities. Dose distributions are calculated using the EGSnrc user-code BrachyDose for{sup 125}I, {sup 103}Pd, and {sup 131}Cs seeds and are compared directly as well as through dose volume histograms and dose metrics for target volumes surrounding surgical sutures. Results: Metallic artifact mitigation techniques vary in ability to reduce artifacts while preserving tissue detail. Notably, images corrected with the fan beam virtual sinogram have reduced artifacts but residual artifacts near sources remain requiring additional use of STR; the 3D median filter removes artifacts but simultaneously removes detail in lung and bone. Doses vary considerably between computational phantoms with the largest differences arising from artifact-affected voxels assigned to bone in the vicinity of the seeds. Consequently, when metallic artifact reduction and constrained tissue assignment within lung contours are employed in generated phantoms, this erroneous assignment is reduced, generally resulting in higher doses. Lung-constrained tissue assignment also results in increased doses in regions of interest due to a reduction in the erroneous assignment of adipose to voxels within lung contours. Differences in dose metrics calculated for different computational phantoms are sensitive to radionuclide photon spectra with the largest differences for{sup 103}Pd seeds and smallest but still considerable differences for {sup 131}Cs seeds. Conclusions: Despite producing differences in CT images, dose metrics calculated using the STR, fan beam + STR, and 3D median filter techniques produce similar dose metrics. Results suggest that the accuracy of dose distributions for permanent implant lung brachytherapy is improved by applying lung-constrained tissue assignment schemes to metallic artifact corrected images.

  16. Determination of prescription dose for Cs-131 permanent implants using the BED formalism including resensitization correction

    International Nuclear Information System (INIS)

    Purpose: The current widely used biological equivalent dose (BED) formalism for permanent implants is based on the linear-quadratic model that includes cell repair and repopulation but not resensitization (redistribution and reoxygenation). The authors propose a BED formalism that includes all the four biological effects (4Rs), and the authors propose how it can be used to calculate appropriate prescription doses for permanent implants with Cs-131. Methods: A resensitization correction was added to the BED calculation for permanent implants to account for 4Rs. Using the same BED, the prescription doses with Au-198, I-125, and Pd-103 were converted to the isoeffective Cs-131 prescription doses. The conversion factor F, ratio of the Cs-131 dose to the equivalent dose with the other reference isotope (Fr: with resensitization, Fn: without resensitization), was thus derived and used for actual prescription. Different values of biological parameters such as ?, ?, and relative biological effectiveness for different types of tumors were used for the calculation. Results: Prescription doses with I-125, Pd-103, and Au-198 ranging from 10 to 160 Gy were converted into prescription doses with Cs-131. The difference in dose conversion factors with (Fr) and without (Fn) resensitization was significant but varied with different isotopes and different types of tumors. The conversion factors also varied with different doses. For I-125, the average values of Fr/Fn were 0.51/0.46, for fast growing tumors, and 0.88/0.77 for slow growing tumors. For Pd-103, the average values of Fr/Fn were 1.25/1.15 for fast growing tumors, and 1.28/1.22 for slow growing tumors. For Au-198, the average values of Fr/Fn were 1.08/1.25 for fast growing tumors, and 1.00/1.06 for slow growing tumors. Using the biological parameters for the HeLa/C4-I cells, the averaged value of Fr was 1.07/1.11 (rounded to 1.1), and the averaged value of Fn was 1.75/1.18. Fr of 1.1 has been applied to gynecological cancer implants with expected acute reactions and outcomes as expected based on extensive experience with permanent implants. The calculation also gave the average Cs-131 dose of 126 Gy converted from the I-125 dose of 144 Gy for prostate implants. Conclusions: Inclusion of an allowance for resensitization led to significant dose corrections for Cs-131 permanent implants, and should be applied to prescription dose calculation. The adjustment of the Cs-131 prescription doses with resensitization correction for gynecological permanent implants was consistent with clinical experience and observations. However, the Cs-131 prescription doses converted from other implant doses can be further adjusted based on new experimental results, clinical observations, and clinical outcomes

  17. Adverse reactions after cosmetic lip augmentation with permanent biologically inert implant materials.

    Science.gov (United States)

    Hoffmann, C; Schuller-Petrovic, S; Soyer, H P; Kerl, H

    1999-01-01

    Augmentation of lips is a common aesthetic procedure that is mostly performed with alloplastic materials or autologous tissue. Various alloplastic injectable implants have been developed for soft tissue augmentation without surgery. Most biologic materials are resorbed within a few months, fluid silicone may migrate, and autologous fat is not ideal for fine contouring of the lips. The search for a biocompatible, permanent, nontoxic, and biologically inert filler material led to the development of some new materials for subdermal or intradermal implantation. Recently Bioplastique, Artecoll, and Gore-Tex have been well established and recommended by many authors. Although these materials meet most of the characteristics that constitute an ideal injectable prosthetic material, we describe 3 examples of adverse reactions after their implantation into lips. PMID:9922021

  18. Preparation and evaluation of serotonin labelled with 125I

    International Nuclear Information System (INIS)

    Radiolabelled serotonin is an important tool for studying serotonin receptors and estimating serotonin levels in plants and animals. In this paper we report the synthesis of serotonin - 125I. Tyrosine Methyl Ester (TME) was first labelled with 125I using chloramine-T method. 125I-TME was then conjugated with serotonin using carbodimide. The labelled conjugate was purified using gel filtration. Yield and radiochemical purity were estimated using electrophoresis and ITLC in different solvent systems. The binding of the purified tracer to serotonin receptors and serotonin antibodies was studied. (author)

  19. Histology study on the dorsal root ganglia of rats with 125I seed brachytherapy at intervertebral foramen

    International Nuclear Information System (INIS)

    Objective: To investigate the effect of the histological changes on rat dorsal root ganglia (DRG) after 125I seed brachytherapy.Methods Twelve adult male Sprague-Dawley rats (150-180 g each) were randomly divided into 6 groups,125I seeds with different activities of 0 (Titanium shell), 14.8, 18.5, 22.2, 25.9 and 29.6 MBq were implanted to 6 groups of rats respectively and the behavioral changes of rats were observed. The rats were killed in different periods after implantation,the morphological changes in DRG and surrounding muscle tissue were observed with an Olympus BX51 optical microscope and then the irradiation doses were estimated. Results: After 125I seed implantation, the movement function of rats was not affected and the weight of rats gained after 7 days. After the titanium shell implantation, very few mild swelling was induced in neuroganglion cells that still had clear nucleolus and normal cytoplasm. At 14 days after 18.5 MBq seed implantation, cell swelling was more serious and cell dehydrating, nuclear condensation and nuclear fragmentation appeared after 30 days. At 60 days after 29.6 MBq of seed implantation, nuclear dissolution and cytoplasmic shrinkage were induced in a large number of cells.In general, the severity of fibrosis was aggravated with the time post-irradiation and the dose in the muscles around the ganglion. Conclusions: After 125I seed implantation,the injury degree of DRG tissue is dose-dependent, and the 125I seed irradiation would have analgesic effect on releasing intractable pain. (authors)

  20. Radioactive 125I seeds inhibit cell growth and epithelial-mesenchymal transition in human glioblastoma multiforme via a ROS-mediated signaling pathway

    International Nuclear Information System (INIS)

    Glioblastoma multiforme (GBM) is the most common primary central nervous system neoplasm in adults. Radioactive 125I seed implantation has been widely applied in the treatment of cancers. Moreover, previous clinical trials have confirmed that 125I seeds treatment was an effective therapy in GBM. We sought to investigate the effect of 125I seed on GBM cell growth and Epithelial-mesenchymal transition (EMT). Cells were exposed to irradiation at different doses. Colony-formation assay, EdU assay, cell cycle analysis, and TUNEL assay were preformed to investigate the radiation sensitivity. The effects of 125I seeds irradiation on EMT were measured by transwell, Boyden and wound-healing assays. The levels of reactive oxygen species (ROS) were measured by DCF-DA assay. Moreover, the radiation sensitivity and EMT were investigated with or without pretreatment with glutathione. Additionally, nude mice with tumors were measured after treated with radiation. Radioactive 125I seeds are more effective than X-ray irradiation in inhibiting GBM cell growth. Moreover, EMT was effectively inhibited by 125I seed irradiation. A mechanism study indicated that GBM cell growth and EMT inhibition were induced by 125I seeds with the involvement of a ROS-mediated signaling pathway. Radioactive 125I seeds exhibit novel anticancer activity via a ROS-mediated signaling pathway. These findings have clinical implications for the treatment of patients with GBM by 125I seeds

  1. Systemic administration of kainic acid induces selective time dependent decrease in [125I]insulin-like growth factor I, [125I]insulin-like growth factor II and [125I]insulin receptor binding sites in adult rat hippocampal formation

    International Nuclear Information System (INIS)

    Administration of kainic acid evokes acute seizure in hippocampal pathways that results in a complex sequence of functional and structural alterations resembling human temporal lobe epilepsy. The structural alterations induced by kainic acid include selective loss of neurones in CA1-CA3 subfields and the hilar region of the dentate gyrus followed by sprouting and permanent reorganization of the synaptic connections of the mossy fibre pathways. Although the neuronal degeneration and process of reactive synaptogenesis have been extensively studied, at present little is known about means to prevent pathological conditions leading to kainate-induced cell death. In the present study, to address the role of insulin-like growth factors I and II, and insulin in neuronal survival as well as synaptic reorganization following kainate-induced seizure, the time course alterations of the corresponding receptors were evaluated. Additionally, using histological preparations, the temporal profile of neuronal degeneration and hypertrophy of resident astroglial cells were also studied. [125I]Insulin-like growth factor I binding was found to be decreased transiently in almost all regions of the hippocampal formation at 12 h following treatment with kainic acid. The dentate hilar region however, exhibited protracted decreases in [125I]insulin-like growth factor I receptor sites throughout (i.e. 30 days) the study. [125I]Insulin-like growth factor II receptor binding sites in the hippocampal formation were found to be differentially altered following systemic administration of kainic acid. A significant decrease in [125I]insulin-like growth factor II receptor sites was observed in CA1 subfield and the pyramidal cell layer of the Ammon's horn at all time points studied whereas the hilar region and the stratum radiatum did not exhibit alteration at any time. A kainate-induced decrease in [125I]insulin receptor binding was noted at all time points in the molecular layer of the dentate gyrus whereas binding in CA1-CA3 subfields and discrete layers of the Ammon's horn was found to be affected only after 12 h of treatment. These results, when analysed with reference to the observed histological changes and established neurotrophic/protective roles of insulin-like growth factors and insulin, suggest possible involvement of these growth factors in the cascade of neurotrophic events that is associated with the reorganization of the hippocampal formation observed following kainate-induced seizures. (Copyright (c) 1997 Elsevier Science B.V., Amsterdam. All rights reserved.)

  2. Effect of 125I interstitial radiotherapy on blood-brain barrier function in normal canine brain

    International Nuclear Information System (INIS)

    Blood-brain barrier (BBB) function was studied in 14 normal dogs at time periods from 7 to 717 days after permanent insertion of 5- to 7-mCi seeds of iodine-125 (125I) for interstitial radiation. The BBB function was measured with carbon-14-labeled alpha aminoisobutyric acid (AIB) and quantitative autoradiography, and expressed as a unidirectional blood-to-brain transfer constant, K. The 125I radiation lesions consisted of three concentric histologically and functionally distinct zones: 1) a central zone of calcified necrosis; 2) a spongy fluid-filled zone; and 3) a narrow rim (2.6 +/- 0.6 mm wide) of viable brain tissue with increased permeability. Within this rim, the mean value of the K of AIB was 5.8 times that of normal cortex. Over the 7- to 392-day time period the value of K remained rather constant, and by 716 days K values had returned to normal. There was moderate regional variation in the value of K; it was highest in the white matter and lowest in the gray matter surrounding the radiation lesion. The radiation lesion progressively increased in size from 7 to 80 days, after which there was little change. This study illustrates that the geographically circumscribed radiation from 125I seeds is accompanied by similarly well-defined changes in BBB function, which may persist for over 1 year following insertion of the 125I seed. This altered BBB function is probably responsible for the cerebral edema associated with 125I interstitial radiotherapy

  3. A study on recombinant human interleukin 2 radioiodinated with 125I (125I-rIL-2) for RIA

    International Nuclear Information System (INIS)

    RIL-2 was labelled with 125I by Iodogen method. The products were purified by HPLC. Analysis of each radiolabelled preparation showed that greater than 95% of the radioiodine was associated with a single protein peak. The specific activity of radioiodinated rIL-2 was approximately 2.2 x 1016-2.8 x 1016 Bq/mol. The 125I-rIL-2 was designed for quantitating human IL-2 with sensitive radioimmunoassay (RIA). The bioactivity of 125I-rIL-2 is good

  4. Preparation of carrier free [125I]iodoHoechst 33258

    International Nuclear Information System (INIS)

    The DNA ligand Hoechst 33258 has been iodinated with carrier-free [125I]iodide by the lactoperoxidase method. The product was separated from other iodination products and the uniodinated compound by preparative thin layer chromatography. 125-labelled Hoechst 33258 is useful as a probe with DNA molecules of defined sequence since the decay of the 125I atom results in the induction of a double-strand break, the location of which can be detected by DNA-sequencing techniques. (author)

  5. An automated, fast and accurate registration method to link stranded seeds in permanent prostate implants

    Science.gov (United States)

    Westendorp, Hendrik; Nuver, Tonnis T.; Moerland, Marinus A.; Minken, André W.

    2015-10-01

    The geometry of a permanent prostate implant varies over time. Seeds can migrate and edema of the prostate affects the position of seeds. Seed movements directly influence dosimetry which relates to treatment quality. We present a method that tracks all individual seeds over time allowing quantification of seed movements. This linking procedure was tested on transrectal ultrasound (TRUS) and cone-beam CT (CBCT) datasets of 699 patients. These datasets were acquired intraoperatively during a dynamic implantation procedure, that combines both imaging modalities. The procedure was subdivided in four automatic linking steps. (I) The Hungarian Algorithm was applied to initially link seeds in CBCT and the corresponding TRUS datasets. (II) Strands were identified and optimized based on curvature and linefits: non optimal links were removed. (III) The positions of unlinked seeds were reviewed and were linked to incomplete strands if within curvature- and distance-thresholds. (IV) Finally, seeds close to strands were linked, also if the curvature-threshold was violated. After linking the seeds an affine transformation was applied. The procedure was repeated until the results were stable or the 6th iteration ended. All results were visually reviewed for mismatches and uncertainties. Eleven implants showed a mismatch and in 12 cases an uncertainty was identified. On average the linking procedure took 42?ms per case. This accurate and fast method has the potential to be used for other time spans, like Day 30, and other imaging modalities. It can potentially be used during a dynamic implantation procedure to faster and better evaluate the quality of the permanent prostate implant.

  6. Error tolerance of Pd-103 Vs I-125 in permanent implants for prostate carcinoma

    International Nuclear Information System (INIS)

    Purpose: Permanent prostate implants use either Pd-103 and I-125 radioactive isotopes. Identical loading techniques are used to implant the prostate despite the difference in energy and half-life between the isotopes. While the differences in the initial dose rate of the isotopes are accounted for in the ideal pre-plans, their effect on placement errors and prostate swelling are not addressed. We have investigated four loading techniques and studied the impact of placement error and organ swelling on prostate volume coverage. Material and Methods: Four loading techniques were studied. a) Uniform loading on a 1 cm grid with 1 cm spacing between seeds in a needle. b) Differential loading on a 0.5 cm grid with variable spacing between seeds in a needle c) Peripheral loading and d) Spiked loading with greater activity in the lobes. Ideal plans were first developed to ensure that at least 99% of the prostate volume received a prescribed dose of 160 Gy and 120 Gy for I-125 and Pd-103 implants, respectively. Placement errors were introduced (1) into the ideal plan and the DVH for the prostate was calculated after enhancing the source activity by 15%. Finally, the ideal plan source strengths were enhanced by 30% to account for both placement error and prostate volume expansion that is associated with the implant procedure, and the plans evaluated for target (prostate volume + 0.5 cm margin) coverage and urethra dose. Results: Percentage of the prostate and target receiving the prescribed dose from various loading techniques. Conclusion: Peripheral loading best covers the target for both I-125 and Pd-103. Pd-103 implants are more sensitive to placement error due to sharp dose fall off. Arbitrarily enhancing the activity per source does not quite eliminate the effects of error and swelling for Pd-103 implants. Increasing the number of sources can reduce this effect, but raises the cost of the implant

  7. Radiolabeling FAU with 125I and its biodistribution in mice

    International Nuclear Information System (INIS)

    Objective: The aim of this study was to label 2'-fluoro-2'-deoxy-l-β-D-arabinofuranosyluracil (FAU) with 125I, and to investigate the characteristics of the labeled compound as well as its bio-distribution in mice. Methods: FAU was radiolabeled with Na125I using the Iodogen method. The Sep-Pak C18 reverse phase column was used to purify the labeled product. The labeling efficiency, radiochemical purity, the in vitro stability and its biodistribution in mice were observed. Results: FAU was successfully labeled with Na125I with the labeling efficiency of (63.12±5.01)%. The radiochemical purity was (98.60 ± 0.52)%. 125I-5-iodo-FAU (FIAU) was stable in PBS and fresh human serum under 37 degree C and the radio-chemical purity remained more than 95.04% after 24 h. Mouse experiment showed that the radiolabeled product was washed out from blood quickly. The uptake expressed as percentage activity of injected dose per gram of tissue (% ID/g) was (4.33±1.00)% ID/g at 0.5 h and (0.71±0.06)% ID/g at 2 h after injection. The 125I-FIAU was mainly excreted through kidney. Conclusions: 125I-FIAU could be obtained by labeling FAU with the Iodogen method with satisfactory labeling efficiency, radiochemical purity and stability. Mouse biodistribution experiment showed it was mainly excreted through kidney. (authors)

  8. Self-expandable medical memorial metallic stent with 125I seeds for the treatment of esophageal carcinoma: a retrospective analysis

    International Nuclear Information System (INIS)

    Objective: To discuss the curative effect and safety of the implantation of self-expandable medical memorial metallic stent with 125I seeds for the treatment of advanced esophageal carcinomas. Methods: Implantation of self-expandable medical memorial metallic stent with 125I seeds was performed in 32 patients with advanced esophageal canner. The clinical data were retrospectively analyzed. The technical success rate, the operation time, the immediate and mid-term effectiveness, the survival time, the complications, the body weight, the blood picture, the immune indexes, the average hospitalization days and hospitalization expenses were analyzed. Results: The average operation time was (18±5) minutes. Successful stent implantation was achieved in all 32 patients (100%). No 125I seeds fell off during the procedure. The remission rate of dysphagia was 100%. Esophageal restenosis occurred in four patients, and displacement of the stent was seed in one patient. One month after the treatment, 90% of patients had a Karnofsky performance score over 60. The mean survival time was (8.7±6.6) months. The average hospitalization time was (7.8±3.7) days and the mean hospitalization cost was (12±3) thousand Chinese Yuan. Conclusion: For the treatment of esophageal carcinomas, the implantation of self-expandable medical memorial metallic stent with 125I seeds is safe, effective and simple. This treatment can markedly improve the symptom of dysphagia and significantly prolong the patient's survival time. (authors)

  9. A comparative study of 19-iodocholesterol-''125I 3-acetate and Na''125I in liquid scintillation measurements

    International Nuclear Information System (INIS)

    A comparative study of performance of 19-iodocholesterol-''125I 3-acetate and sodium iodine samples labelled with ''125 I is presented for liquid scintillation counting measurements. Quench effect, count rate stability and spectral evolution of samples have been followed for several weeks in Toluene, Hisafe II, Instagel, Dioxane-naphthalene and Toluene-alcohol scintillators. Organic samples have negligible quench effect in the interval of I''-concentration of 0-90 ug and inorganic samples only show a very small variation, lower than 12%, for Dioxane-naphthalene, in the same range of concentration. Satisfactory stability is obtained in general for both, organic and inorganic samples, but small counting losses, 0.03% for 19-iodocholesterol-''125I 3-acetate samples in Toluene-alcohol and 0.04% for Na''125I samples in Dioxane-naphthalene and Toluene-alcohol, have been reported. (Author) 8 refs

  10. Synthesis and comparison of different 125I-estradiol analog for estrogen radio receptor assay

    International Nuclear Information System (INIS)

    Radio Receptor Assay (RRA) for the Estrogen Receptor (ER) is important in cancer diagnostic and drug designation. 7 kinds of 125I-Estradiol analogs: 125I-Estradiol-6-CMO-His, 125I-Estradiol-3-CME-His, 125I-Estradiol-17-HS-His, 2-125I-Estradiol, 4-I-Estradiol, 2, 4-2 125I-Estradiol, 16? 125I-Estradiol were synthesized and compared for Estrogen Radio Receptor Assay. It was found that 16? 125I-Estradiol was better than 3H-Estradiol and other 125I-Estradiol analogs mentioned above for the RRA of Estrogen Receptor. (authors)

  11. Permanent interstitial implantation of 125iodine in case of carcinomas of the oral and the oropharynx

    International Nuclear Information System (INIS)

    The authors present their first experiences gained during the last year with the permanent implantation of 125iodine seeds in thirty patients suffering from carcinomas of the oral cavity and the oropharynx. The properties and advantages of 125iodine, the method of implantation, the dosimetry and the problems of radioprotection are particularly underlined. In every case, we apply pre- or postoperative external radiotherapy, i. e. we expose the primary tumor to a dose of 50 Gy fractionated in the usual manner over four or five weeks. This combined treatment is intended to overcome the resistance to therapy of ORL malignomas and to obtain a high local rate of tumor control and a low rate of functional and cosmetic troubles. (orig.)

  12. Exclusive curietherapy by permanent iodine-125 implants: selection of patients and results after eight years

    International Nuclear Information System (INIS)

    The authors report a retrospective study which assesses the results obtained over eight years and the toxicity of an exclusive curietherapy by permanent iodine-125 implants performed at the Nancy centre of struggle against cancer. More than five hundred patients have been treated between December 1999 and December 2007, a first group comprising patients suffering from a low risk cancer and a second group suffering from a medium risk cancer. The authors discuss the survival rates, the existence of side effects, and rectal toxicity results. Short communication

  13. Evaluation of physician eye lens doses during permanent seed implant brachytherapy for prostate cancer

    International Nuclear Information System (INIS)

    Treatment of low grade prostate cancer with permanent implant of radioactive seeds has become one of the most common brachytherapy procedures in use today. The implant procedure is usually performed with fluoroscopy image guidance to ensure that the seeds are deployed in the planned locations. In this situation the physician performing the transperineal implant is required to be close to the fluoroscopy unit and dose to the eye lens may be of concern. In 1991 the International Commission on Radiological Protection (ICRP) provided a recommended dose limit of 150 mSv yr?1 for occupational exposures to the lens of the eye. With more long term follow-up data, this limit was revised in 2011 to 20 mSv yr?1. With this revised limit in mind, we have investigated the dose to the lens of the eye received by physicians during prostate brachytherapy seed implantation. By making an approximation of annual workload, we have related the dose received to the annual background dose. Through clinical and phantom measurements with thermoluminescent dosimeters, it was found that the excess dose to the physician’s eye lens received for a conservative estimate of annual workload was never greater than 100% of the annual background dose. (paper)

  14. Intraoperative modification method in the transperineal permanent implant of I-125 seed in prostate cancer

    International Nuclear Information System (INIS)

    In the Department of Radiation Therapy and Oncology, International Medical Center of JAPAN, transperineal permanent implant (TPI) of I-125 seeds have been performed since April 2004. In April the planning method was changed from the preplanning to the intraoperative modification method in April 2006. Various dose parameters were compared between the 106 patients treated by preplanning and the 42 patients undergoing the intraoperative modification. The mean operation time was 84 minutes in the preplanned method and 92 minutes in the intraoperative modification. The prostatic volume reduced at the postplanning, compared to the preplanning. Dosimetric parameters of prostate (V100, V150, and D90%) diminished at the time of postplanning with a statistical significance, while the degree of the reductions was greater in the patients treated by the preplanned method. The mean prostate V100 of the preplanning and the intraoperative modification was 89% and 93.3%, respectively, and the mean prostate D90% was 100% and 111%, respectively, both with a statistically significant difference. In contrast, urethral and rectal dose parameters were the same in both methods. The intraoperative modification method was useful to attain the high quality permanent implant of I-125 seeds. (author)

  15. Dosimetry of ophthalmic applications using 125I seed sources

    International Nuclear Information System (INIS)

    Intraocular melanoma is the most common primary malignancy of the eye and radiation therapy using ophthalmic plaque has proved successful for its management. The dose prescription point recommended for 125I eye plaque therapy is usually 5 mm from tumour base centre for tumours with 5 mm or less height and tumour apex, otherwise. A computational programme was written to generate data for the dosimetry of eye plaque therapy using 125I seeds. Variation of central axis depth dose and isodose distributions at reference depth have been studied for different diameter plaques. The reference dose rate chosen for a clinical application, based on treatment planning software, was compared with that derived from the data generated in the present study. The dosimetry data generated and presented in this paper will help pre-planning of ophthalmic applications, using 125I seeds. (author)

  16. Cytotoxicity of an 125I-labelled DNA ligand

    International Nuclear Information System (INIS)

    The subcellular distribution and cytotoxicity of a DNA-binding ligand [125I]-Hoechst 33258 following incubation of K562 cells with the drug was investigated. The ability of a radical scavenger, dimethyl sulphoxide, to protect cells from the 125I-decay induced cell death was also studied. Three different concentrations and specific activities of the drug were used to provide different ligand : DNA binding ratios. The results demonstrated a trend toward improved delivery of the ligand to the nucleus and to chromatin at higher ligand concentrations, with concomitant increased sensitivity to 125I-decay induced cytotoxicity and decreased protection by dimethyl sulphoxide. This correlation of radiobiological parameters with subcellular drug distribution is consistent with the classical dogma that attributes cytotoxicity to DNA double-stranded breakage in the vicinity of the site of decay, where the high LET nature of the damage confers minimal sensitivity to radical scavenging

  17. Cytotoxicity of an {sup 125}I-labelled DNA ligand

    Energy Technology Data Exchange (ETDEWEB)

    Karagiannis, T.C.; Lobachevsky, P.N.; Martin, R.F. [Peter MacCallum Cancer Inst., Melbourne (Australia). Trescowthick Research Laboratories

    2000-11-01

    The subcellular distribution and cytotoxicity of a DNA-binding ligand [{sup 125}I]-Hoechst 33258 following incubation of K562 cells with the drug was investigated. The ability of a radical scavenger, dimethyl sulphoxide, to protect cells from the {sup 125}I-decay induced cell death was also studied. Three different concentrations and specific activities of the drug were used to provide different ligand : DNA binding ratios. The results demonstrated a trend toward improved delivery of the ligand to the nucleus and to chromatin at higher ligand concentrations, with concomitant increased sensitivity to {sup 125}I-decay induced cytotoxicity and decreased protection by dimethyl sulphoxide. This correlation of radiobiological parameters with subcellular drug distribution is consistent with the classical dogma that attributes cytotoxicity to DNA double-stranded breakage in the vicinity of the site of decay, where the high LET nature of the damage confers minimal sensitivity to radical scavenging.

  18. Dose distribution of 125I seed sources in brachytherapy prostate cancer model

    International Nuclear Information System (INIS)

    Objective: To study the dose distribution of the radioactive 125I seeds sources in the treatment of prostate cancer and also to explore the more effective method for improving treatment planning system (TPS). Methods: Choose the designated TPS and use TLDs dosimeter based on a prostate cancer model. Finally stimulated measurement was focused on dose distribution in prostate cancer. The number of 125I seed sources implanted was 89, each with 1.37 × 107 ( ± 5% ) Bq. Results: Maximum dose of every layer ranged from 151 to 241 Gy, by 4.1% to 66.0% higher than the prescribed dose (145 Gy). The Minimum dose of every layer ranged from 101 to 128 Gy, by 12% to 30% higher than the prescribed dose. The maximum dose of normal tissue at 10 mm from the edge of model ranged from 46 to 91 Gy. The deviation was 44% -63% compared with the prescribed dose. Conclusions: The designated TPS shows that it could be used as a practical guide for treatment of prostate cancer with the radioactive 125I seed sources. The research methods offered by the study can provide evaluation of the TPS. (authors)

  19. The experimental study of 125I seed brachytherapy in human hepatocellular carcinoma bearing nude mice

    International Nuclear Information System (INIS)

    Objective: To explore the effect and influence of tumor growth, cell proliferation and apoptosis related protein of 125I seed brachytherapy in human hepatocellular carcinoma (HHC) bearing nude mice. Methods: Twelve HHC BEL-7402 cells bearing nude mice were equally divided into treated and control group. One 125I seed with 33.3 MBq was implanted into each mouse in treated group. Afterward the dimensions of tumor in both groups were measured every 3-4 d and also the tumor volume inhibition rates were calculated. Twenty-one days later, nude mice sacrificed and routine pathological examination proceeded. The expression of proliferating cell nuclear antigen (PCNA), bcl-2 and bax were detected by immunohistochemical methods. Results: The maximum tumor inhibition rate of treated group was 49.2%. Routine pathological examination found degenerative necrosis at the site was nearby the seed but the alive tumor cell still presented faraway from the seed. The expression of PCNA and the ratio of bcl-2/bax in treated group were lower than those in control group. Conclusion: The sustained irradiation of 125I seed brachytherapy can direct kill the HHC cell in nude mice or inhibit the proliferation of tumor cells. (authors)

  20. Realization of a permanent implantable pulsatile impeller heart with magnetically suspended motor.

    Science.gov (United States)

    Qian, K X; Zheng, M

    1997-07-01

    A permanent impeller heart that could work for years was once an idea. However, now this idea is turning into reality through the use of the magnetically suspended motor. Recently, with our implantable pulsatile impeller pump, 3 left ventricular assisted calves survived for about 2 months (62, 54, and 46 days, respectively). The termination of the experiments was related to wear of the mechanical bearing, which resulted in vibration of the rotor and pump failure. All the experimental animals were in good condition prior to pump failure. It seemed as if the experiments could have lasted indefinitely if the bearing had not failed. All the hematological and biochemical data of the calves remained in normal or acceptable ranges; neither blood damage nor organ dysfunction of any animal was detected. During autopsy, no severe thrombus formation was found in the pump or vessels although a low dose of heparin (0.5-0.8 g/h) was given to increase the activated coagulation time (ACT) to 1.5-2.0 times its normal value. To solve the problem of bearing wear, a magnetically suspended motor was investigated and applied to the impeller pump. On the opposite sides of a disc connected to the rotor, 2 permanent magnet rings were embedded, one for driving and the other for axial suspension. Because both the driving and suspending coils with iron cores attract the disc, no radial bearing was needed. This newly devised impeller heart promises to have long-term and permanent applications. PMID:9212937

  1. Chromosome aberrations induced by the Auger electron emitter (125)I.

    Science.gov (United States)

    Schmitz, Sabine; Oskamp, Dominik; Pomplun, Ekkehard; Kriehuber, Ralf

    2015-11-01

    DNA-associated Auger electron emitters (AEE) cause cellular damage leading to high-LET type cell survival curves indicating an enhanced relative biological effectiveness. Double strand breaks (DSBs) induced by Iodine-125-deoxyuridine ((125)I-UdR) decays are claimed to be very complex. To elucidate the assumed genotoxic potential of (125)I-UdR, chromatid aberrations were analysed in exposed human peripheral blood lymphocytes (PBL). PBL were stimulated with medium containing phytohaemagglutinin (PHA). After 24h, cultures were labelled with (125)I-UdR for 18h (activity concentration 1-45 kBq) during the S-phase. Following standard cytogenetic procedure, at least 100 metaphases were analysed microscopically for each activity concentration. Cell death was measured by apoptosis assay using flow cytometry. Radiation doses were determined by using point kernel calculations. After 18h labelling with (125)I-UdR the cell cycle distribution is severely disturbed. About 40% of PBL are fully labelled and 20% show a moderate labelling of (125)I-UdR, whereas 40% of cells remain un-labelled. The dose-response relationship fits to a polynomial curve in the low dose range, whereas a linear fit supplies a better estimation in the high dose range. Even the lowest dose of 0.2Gy leads to a 13-fold increase of aberrations compared to the controls. On average every fifth (125)I-decay produces a single chromatid aberration in PBL. Additionally, a dose-dependent increase of cell death is observed. (125)I-UdR has a very strong genotoxic capacity in human PBL, even at 0.2Gy. Efficiently labelled cells displaying a prolonged cell cycle compared to moderately labelled cells and cell death contribute substantially to the desynchronisation of the cell cycle. Our data, showing for the first time, that one (125)I-decay induces ∼ 0.2 chromatid aberrations, are in very good accordance to DSB data, stating that ∼0.26 DSB are induced per decay, indicating that approximately every DSB is converted into a chromatid aberration. PMID:26520374

  2. Measurement of 125I by liquid scintillation methods

    International Nuclear Information System (INIS)

    The decay scheme of 125I is examined for the explanation of the observed pulse height spectrum and counting efficiency measured by liquid scintillation methods. The pathways of energy release in the form of kinetic energy of electrons (conversion of Auger electrons) is explained. Two major energy groups are predicted at 12 and 40 keV. These two groups were observed in the liquid scintillation systems. The measured counting efficiency in an unquenched emulsifier scintillator solution and a coincidence type liquid counter was 76%. The effects of quenching on the counting efficiency and pulse height spectrum of 125I were measured. (Auth.)

  3. Implantation port-catheter permanent indwelling of pulmonary artery in treating lung metastasis from HCC

    International Nuclear Information System (INIS)

    Objective: To observe the efficacy of a percutaneous implantation port-catheter permanent indwelling pulmonary artery for regional chemotherapy of the metastatic lung cancer from HCC. Methods: Between 1995 and 1999, 62 patients (42 males, 20 females; mean age 46 years) suffering from the metastatic lung cancer from HCC underwent percutaneous implantation of port-catheter permanent indwelling pulmonary artery using the right subclavian vein. In 19 patients with metastatic tumor located on one side of the lung, an indwelling catheter was placed into the ipsilateral side pulmonary artery. With metastasis of both sides, the catheter was inserted into the main trunk of pulmonary artery. The regimens of the chemotherapy were 5-FU + CDDP + MMC(FDM) or 5-FU + CDDP + MMC(FDA). Results: The interventional procedure was successfully completed in all 62 cases (100%). The complications occurred in 8% cases, including infections (3.2%), unhealed wound (1.6%) and pneumothorax (3.2%). The treatment effects of 3-months after the procedure were as follows: the obvious decrease of lung tumor size was 35.5%; stable disease (SD) 32.3% and progressive disease (PD) 32.3%. 6 months follow-up: 12 patients were dead (12/62) and the others are still doing well. The response rates were 22.6%, partial response (PR) 32.3%; stable disease (SD) 25.8% and progressive disease (PD) 32.3%. Conclusions: The percutaneous implantation techniques of pulmonary arterial port-catheter could be a good method in the treatment of metastatic lung cancer from HCC because of it is simple, with few complications and positive effect

  4. Optimal needle arrangement for intraoperative planning in permanent I-125 prostate implants

    International Nuclear Information System (INIS)

    One limitation of intraoperative planning of permanent prostate implants is that needles must already be in the gland before planning images are acquired. Improperly placed needles often restrict the capability of generating optimal seed placement. We developed guiding principles for the proper layout of needles within the treatment volume. The Memorial Sloan-Kettering Cancer Center planning system employs a genetic algorithm to find the optimal seed implantation pattern consistent with pre-assigned constraints (needle geometry, uniformity, conformity and the avoidance of high doses to urethra and rectum). Ultrasound volumes for twelve patients with I-125 implants were used to generate six plans per patient (total 72 plans) with different needle arrangements. The plans were evaluated in terms of V100 (percentage prostate volume receiving at least the prescription dose), U135 (percentage urethra volume receiving at least 135% of prescription dose), and CI (conformity index, the ratio of treatment volume to prescription dose volume.) The method termed POSTCTR, in which needles were placed on the periphery of the largest ultrasound slice and posterior central needles were placed as needed, consistently gave superior results for all prostate sizes. Another arrangement, labelled POSTLAT, where the needles were placed peripherally with additional needles in the posterior lateral lobes, also gave satisfactory results. We advocate two needle arrangements, POSTCTR and POSTLAT, with the former giving better results. (author)

  5. A comparative study of 19-iodo cholesterol-125I 3-acetate and Na 125I in liquid scintillation measurements

    International Nuclear Information System (INIS)

    A comparative study of performance of 19-iodo cholesterol 125I 3-acetate and sodium iodide samples labeled with 125I is presented for liquid scintillation counting measurements. Quench effect, count rate stability and spectral evolution of samples have been followed for several weeks in Toluene, Hisafe II, Instagel, Dioxane-naphthalene and Toluene-alcohol scintillators. Organic samples have negligible quench effect in the interval of I concentration of 0-90 ?g and inorganic samples only show a very small variation, lower than 12%, for Dioxane-naphthalene, in the same range of concentration. Satisfactory stability is obtained in general for both, organic and inorganic samples, but small counting losses, 0.03% for 19-iodocholesterol 1 I 3-acetate samples in Tolue ne-alcohol and 0 .04% for Na 125I samples in Dioxane-naphthalene and Toluene-alcohol, have been reported. (Author) 8 refs

  6. Interaction of 125I-glucagon with isolated rat hepatocytes

    International Nuclear Information System (INIS)

    The accumulation of 125I-glucagon by isolated rat hepatocytes was investigated. Hormone receptor binding and other cellular events were integrated to provide a comprehensive description of glucagon-hepatocyte interactions. The goal of this study was to investigate mechanisms regulating glucagon-receptor binding and biologic response in intact cells

  7. R.I.S.-125 125I air monitor system

    International Nuclear Information System (INIS)

    We have developed at NRCN a prototype of a continuous K-Ray air monitoring (CAM) system called 'R.1.S.-125' (Radioactive Isotope Sampler for 125I). The system. was checked according to ANSI N42.17B -1989 (authors)

  8. Infections associated with permanent pacemakers and implanted cardioverter-defibrillator devices. A 10-year regional study in Denmark

    DEFF Research Database (Denmark)

    Smit, Jesper; Korup, Eva; Schønheyder, Henrik C

    2010-01-01

    Abstract Endocarditis and localized pocket infections are recognized as serious adverse events in patients with implanted cardiac impulse generators. We have undertaken a 10-y retrospective study in North Denmark Region (population 0.5 million) in order to elucidate the clinical spectrum, causative microorganisms, management and outcome. Infections associated with permanent pacemakers (PPM) and implanted cardioverter-defibrillator (ICD) devices were identified by searching hospital databases. Ni...

  9. Treatment of prostate adenocarcinoma permanent implants with I 125: first experience in Uruguay

    International Nuclear Information System (INIS)

    Full text: Objective: To report on the treatment done, toxicity and development of a group of adenocarcinoma patients with localized prostate brachytherapy implants permanent I125. Material and Methods. 37 patients were treated in the period 2001 to 2004 at the Military Hospital Central by this treatment modality. All of them were performed before implantation planning, which consisted of the volumetric calculation and calculation prostate dosimetry that included transrectal prostate ultrasound 3-5 weeks before the procedure. all patients had pathological confirmation of the lesion showed PSA values less than 11 ng / ml and Gleason score less than 7. 70% of patients received neo-adjuvant hormone therapy. In 5 patients an interactive planning system was performed computerized dosimetry, using sequential ultrasound imaging planes, allowed the dosimetric analysis before terminate the procedure and make necessary adjustments if the dose distribution did not conform. This additional dosimetric study we have not been described by other authors. Prescribed in the first 10 patients was dose 144 Gy and 160 Gy in subsequent. All patients underwent post implant CT waffle grid after 15 days of the procedure. analyzed the dose volume histogram (HDV) and D90 values??. Clinical follow-up was performed and PSA biochemical .. Preliminary Results: 33 patients were in local control without biochemical failure. Currently 4 patients presented biochemical recurrence with PSA values ??between 4 and 6 ng / ml. In neither disease was found at a distance and then raises confirmation tumor biopsy active presence will undergo surgical treatment protocols localized prostate cancer. HDV values ??D90 and are consistent with the informed by the international literature will be presented. No patient required hospitalization prolonged (greater than 24 hours) or use of higher analgesics. 2 patients had acute urinary retention (G II complication) between the tenth and twentieth day, the rest of the patients had minor complications (G I), hematuria spontaneously fell to fourth day of treatment (1), mild perineal hematoma (1). Most patients dysuria presented from the first week I was treated with alpha-blockers.Conclusions: Prostate brachytherapy with permanent implants is a procedure I125 well tolerated, minimally invasive, Given the short follow-up time of regard them as preliminary results in this selected patient population

  10. Bypassing the learning curve in permanent seed implants using state-of-the-art technology

    International Nuclear Information System (INIS)

    Purpose: The aim of this study was to demonstrate, based on clinical postplan dose distributions, that technology can be used efficiently to eliminate the learning curve associated with permanent seed implant planning and delivery. Methods and Materials: Dose distributions evaluated 30 days after the implant of the initial 22 consecutive patients treated with permanent seed implants at two institutions were studied. Institution 1 (I1) consisted of a new team, whereas institution 2 (I2) had performed more than 740 preplanned implantations over a 9-year period before the study. Both teams had adopted similar integrated systems based on three-dimensional (3D) transrectal ultrasonography, intraoperative dosimetry, and an automated seed delivery and needle retraction system (FIRST, Nucletron). Procedure time and dose volume histogram parameters such as D90, V100, V150, V200, and others were collected in the operating room and at 30 days postplan. Results: The average target coverage from the intraoperative plan (V100) was 99.4% for I1 and 99.9% for I2. D90, V150, and V200 were 191.4 Gy (196.3 Gy), 75.3% (73.0%), and 37.5% (34.1%) for I1 (I2) respectively. None of these parameters shows a significant difference between institutions. The postplan D90 was 151.2 Gy for I1 and 167.3 Gy for I2, well above the 140 Gy from the Stock et al. analysis, taking into account differences at planning, results in a p value of 0.0676. The procedure time required on average 174.4 min for I1 and 89 min for I2. The time was found to decrease with the increasing number of patients. Conclusion: State-of-the-art technology enables a new brachytherapy team to obtain excellent postplan dose distributions, similar to those achieved by an experienced team with proven long-term clinical results. The cost for bypassing the usual dosimetry learning curve is time, with increasing team experience resulting in shorter treatment times

  11. Preparation of 125I-labeled monoclonal antibody of bladder neoplasm using lactoperoxidase

    International Nuclear Information System (INIS)

    125I-labelled monoclonal antibody of bladder neoplasm (125I-L4B4) is prepared using lactoperoxidase. The in-vivo radioactive distribution of 125I-L4B4 in bare mice shows that 125I-L4B4 concentrates in the tumour

  12. Commercial production of 125I-fibrinogen injection

    International Nuclear Information System (INIS)

    In 1975 Health Protection Branch approval was received to distribute 125I-Fibrinogen Injection. Since that time over 30.000 vials of this drug have been prepared and used in the detection of venous thrombosis. Diagnosis of venous thrombosis with fibrinogen leg scanning depends on the incorporation of 125I-Fibrinogen into the thrombus, which is then detected by measuring the consequent increase of overlying surface radioactivity using a small Na(Tl) detector. The preparation of the drug relies on careful donor selection to minimize the chance of transmitting hepatitis. Careful separation of the fibrinogen is necessary to ensure that a high concentration of clottable protein is available for iodination. Fibrinogen having a clottable protein content in excess of 80% is iodinated usino. the ICl method. This product must have a consistent high quality. The control procedures used to examine the quality of each batch are described. (author)

  13. Preparation and evaluation of 125I-aflatoxin B1

    International Nuclear Information System (INIS)

    Aflatoxin B1 (AfB1), present in fungus infested crops is highly carcinogenic and is measured by immunoassays. 125I labeled aflatoxin B1 is a key reagent for development of radioimmunoassay (RIA) which exhibits less interference and better sensitivity than other immunoassays. Since AfB1 lacks suitable functional groups for radiolabeling, an oxime derivative of AfB1 was synthesised and evaluated by UV-spectrophotometry and 1H NMR spectroscopy. 125I-histamine was conjugated to AfB1 oxime by mixed anhydride method and purified by solvent extraction followed by TLC. The tracer obtained was immunoreactive, stable as ethanolic solution and could be used in RIA. (author)

  14. The metabolism of 125I-gelatin in rabbits

    International Nuclear Information System (INIS)

    125I-labeled gelatin sponge was made by special technique. Healthy adult rabbits were anesthetized by amytal. Then the thigh-bone was exposed and drilled a hole. The bone marrow and bone substance were taken out and the bone-cave was planted with 125I-gelatin sponge. At 14 or 30 days after planting, the radioactivities of the liver, lung, kidney, genitals as well as the blood (obtained from ear-vein every two days after planting) were measured. The results showed that the radioactivity remained high in all of these tissues and blood from the sixth day to the eighteenth day after planting. The biological half-life in abdominal cavity and bone were 8.5 days and 9.2 days respectively. At 14 days after planting, liver spleen and kidney exhibited high level of radioactivity, while low radioactivity was found in other organs

  15. Amino acid tolerance test using L-?-phenylalanine-125I

    International Nuclear Information System (INIS)

    An amino acid tolerance test is described. L-?-phenylalanine-125I was used as representative of L-amino acids. The change in radioactivity of the blood after giving a test dose of tagged L-?-phenylalanine was also investigated. L-?-phenylalanine-125I tolerance curves were found to be irreproducible when the test dose was given without a carrier. The addition of 2.5 g untagged phenylalanine as a carrier to the test dose allowed a reproducible and precise type of tolerance curves. Metformin in a dose of 0.5 g t.d.s. for three days induced an inhibitory effect on amino acid absorption in normal persons. (author)

  16. Detection of thrombocyte antibodies by 125I labeled protein A

    International Nuclear Information System (INIS)

    Protein A from Staphylococcus aureus interacts in a specific manner with most subclasses of human IgG. In the present study a method is described which utilizes Protein A labeled with 125I for the detection of antibody sensitization of platelets. The clinical applicability of the test for detection of in vivo or in vitro sensitization is demonstrated in three patients with platelet antibodies. (author)

  17. Preparation of 19-iodocholesterol labelled with 125 I

    International Nuclear Information System (INIS)

    In this paper a new method of synthesis of 19-iodo cholesterol labelled with ''125 I, from commercial cholesterol, is described. Its high chemical (96%) and radiochemical (99.9%) purities high yield and short time of preparation permit us to dispose or a more accessible labelled compound, which results appropriates for clinical investigations and in the diagnosis of disturbances of the suprarenal glands. (Author) 9 refs

  18. Production of 125I seed sources for brachytherapy uses

    International Nuclear Information System (INIS)

    The production of radioactive sources of 125I, used mainly for the brachytherapy of prostate and ocular cancer, is a work that is being carried out in the plant of production of radioisotopes (PPR) of the Nuclear Center Racso of the IPEN. The employed methodology is based on the 125I physical-chemistry adsorption at silver wires coated with palladium. In the realization of the tests, it has been considered the procedure used by India and Iran participants of this CRP. In the execution of this work, the 131I radioisotope is been used simulating the 125I, because in the PPR-IPEN we produce the 131I. In total 50 samples were used, they were divided in ten groups. In first place with nine working groups, the optimum conditions for work for the coating of the silver wires with palladium were obtained, these being the following: simple method, employing PdCl2 0.1 m, pH of 5.5 to 6.5 and a temperature of 100 deg. C. Later on, a series of tests were carried out to determine the appropriate parameters for the adsorption of 131I in the previously treated wires, these being the following: carrier concentration of Ki 0.03 m, time of adsorption of 6 hours, and temperature of 70 deg. C. Finally, the percentage of 131I adsorption was obtained in the silver wires tried previously with palladium chloride solution of 98.24%. The control of leachability was made, having very good results. To confirm these previously mentioned parameters, a test was made with ten pieces of silver wires, corresponding to the group 10, giving the confirmation as a result of these. Also, samples of the titanium tube have been sent for test with microplasma welding to a French company: air welding liquidates export. With these results obtained, subsequently the production of these radioactive sources will be carried out employing 125I as a radioisotope. (author)

  19. Absolute measurement of the 125I desintegration rate

    International Nuclear Information System (INIS)

    The procedure followed by the Laboratorio de Metrologia Nuclear at the IPEN (Instituto de Pesquisas Energeticas e Nucleares), Sao Paulo - Brazil, for the absolute determination of the 125I desintegration rate by means of the X-(X,Π) Coincidence and Sum-Peak methods is described. The results were submitted to the BIPM (Bureau International des Poids et Mesures), France, for an International Comparison of this radionuclide. (author)

  20. Labeling Lanreotide with 125I and 188Re

    International Nuclear Information System (INIS)

    Lanreotide is a new somatostatin analogue. It can bind to human somatostatin receptor (hSSTR) subtype 2 through 5 with high affinity and to hSSTR subtype I with low affinity. We investigate labeling condition, quality control and stability in vitro of 125I-Lanreotide and 188Re-lanreotide respectively. (A) Lanreotide is labeled with 125I using Chloramine T. The effect of reaction condition (such as reaction time, pH value, Lanreotide amount, quantity of Chloramine T and reaction volume) on labeling yield is investigated in detail. (B) The labeling yield and radiochemical purity (RP) is measured with paper chromatography (PC) and Sep-Pak C18 Cartridge. (C) The stability of 125I-Lanreotide in vitro is investigated by labeling compound incubating for 48 hours at 37 deg C in the 0.9% sodium chloride solution and RP is tested by PC at specific time intervals. (D) Lanreotide is labeled directly with 188Re via the mixture of citrate and tartate using stannous chloride as reduced agent. The influence of reaction conditions such as pH, temperature, amount of stannous chloride, amount of Lanreotide and reaction time on labeling yield is investigated in detail. At the time, the stability in vitro quality control and animal test are evaluated

  1. Comparison of [125I]somatomedin A and [125I]somatomedin C radioreceptor assays for somatomedin peptide content in whole and acid-chromatographed plasma

    International Nuclear Information System (INIS)

    The placental membrane radioreceptor assay was used to measure the levels of somatomedin (SM) peptides in plasma. Displacement of both [125I]somatomedin A ([125I]SM-A) and [125I]somatomedin C ([125I]SM-C) by normal whole plasma, the peptide fraction of acid-chromatographed plasma, and a partially purified, insulin-free SM preparation were compared. The peptide fraction of plasma was isolated by acid chromatography over Sephadex G-50 in 0.25 M formic acid with a yield of greater than or equal to 90%, as determined by bioassay and [125I]SM. In the case of [125I]SM-A, the dose-response curves for whole plasma, acid-chromatographed plasma, and the standard SM preparation were parallel (P > 0.2). In contrast, for [125I]SM-C, the dose-response curves for acid-chromatographed plasma and the purified SM preparation were parallel (P > 0.2), but both differed significantly from that of whole plasma (P 125I]SM-A is a valid measure of SM peptide concentration, while radioreceptor assay of unextracted normal plasma using [125I]SM-C, in our hands, is not. Acid chromatography of plasma before its assay is an uncomplicated procedure which allows valid and precise measurement of SM peptide content using either [125I]SM-A or [125I]SM-C

  2. The Anderson nomograms for permanent interstitial prostate implants: a briefing for practitioners

    International Nuclear Information System (INIS)

    Purpose: The objective of this report is to re-evaluate the role of the Anderson nomograms in treatment planning for permanent prostate implants. The incentive for revisiting this topic concerns three issues: (1) Although nomograms continue to be used in many centers for ordering seeds, few centers use them during treatment planning; (2) Whereas nomograms were designed to deliver a minimum peripheral dose for a uniform distribution of seeds in the gland, many practitioners use peripheral seed loading patterns to reduce urethral toxicity; and (3) As preoperative and intraoperative treatment planning is becoming standard, the apparent role of nomograms is diminished. The nomogram method is reviewed in terms of: (1) total activity predicted, (2) target coverage (as planned in the operating room and as calculated from postimplant computed tomography studies), and (3) reproducibility (i.e., patient-to-patient and planner-to-planner variability). In each case, the computer-optimization system for intraoperative planning currently in use at our institution was taken as the 'gold standard'. Methods and Materials: We compared for the same patient the results of nomogram planning to those yielded by genetic algorithm (GA) optimization in terms of total activity predicted (n=20 cases) and percent target coverage (n=5 cases). Furthermore, we examined retrospectively the dosimetry of 61 prostate implants planned with the GA (n=27) and the current implementation of Anderson nomograms (n=34). Results: Nomogram predictions of the total activity required are in good agreement (within 10%) with the GA-planned activity. However, computer-optimized plans consistently yield superior plans, as reflected in both pre- and postimplant analyses. We find also that user (specifically, treatment planner) implementation of the nomograms may be a major source of variability in nomogram planning - a difficulty to which robust computer optimization is less prone. Conclusions: Nomograms continue to be useful tools for predicting the total required activity for volume implants, and thus for performing an independent check of this quantity. Not unexpectedly, computer optimization remains the preferred planning method. Generally, nomogram-guided implants do not incorporate structures other than the treatment volume into the planning process. Further yet, they deliver a lower dose than that prescribed and result in greater variability among plans than computer-optimized treatments. In summary, nomograms (1) remain an efficient quality assurance tool for computer-generated plans, (2) serve as a good predictor of the number of seeds required for ordering purposes, and (3) provide a simple and dependable backup planning method in case the intraoperative planning system fails

  3. Labeling Lanreotide with 125I and 188Re. China

    International Nuclear Information System (INIS)

    Lanreotide (D-?-Nal-Cys-Try-D-Trp-Lys-Val-Cys-Thr-NH2) is a new somatostatin analogue. It can bind to human somatostatin receptor (hSSTR) subtype 2 through 5 with high affinity and to hSSTR subtype 1 with low affinity. We investigate labeling condition, quality control and stability in vitro of 125I-Lanreotide and 188Re-lanreotide respectively. (A) Lanreotide is labeled with 125I using Chloramine T. The effect of reaction condition (such as reaction time, pH value, Lanreotide amount, quantity of Chloramine T and reaction volume) on labeling yield is investigated in detail. (B) The labeling yield and radiochemical purity (RP) is measured with paper chromatography (PC) and Sep-Pak C18 Cartridge. For PC method, 125I-Lanreotide is spotted on the Whatman No.1 paper and developed in the mixture of CH3CH2CH2CH2OH and CH3CH2OH and NH4OH (v/v/v=5:2:1), the Rf value of every component in the mobile phase is given in table 1. For Sep-Pak C18 Cartridge methods each cartridge is washed with 10 ml of ethanol followed by 10 ml of iso-CH3CH2CH2OH solution. Aliquots of 0.1 mI sample is loaded onto the cartridge, unbound peptide (sodium iodine-125) is eluted with 5 ml of 0.5mol/L sodium acetate solution, 125I-Lanreotide is eluted with 5 mI of 95% aqueous ethanol solution. (C) The stability of 125I-Lanreotide in vitro is investigated by labeling compound incubating for 48 hours at 37 deg. C in the 0.9% sodium chloride solution and RP is tested by PC at specific time intervals. (D) Lanreotide is labeled directly with 188Re via the mixture of citrate and tartate using stannous chloride as reduced agent. The influence of reaction conditions such as pH, temperature, amount of stannous chloride, amount of Lanreotide and reaction time on labeling yield is investigated in detail. At the time, the stability in vitro quality control and animal test are evaluated

  4. Study on agroecology contamination from 125I gas and control measures in a simulated ecosystem

    International Nuclear Information System (INIS)

    The study was made in an air-tight space in which a simulated agricultural ecosystem was contaminated from 125I gas. The contents of the study were summarized as follows: The space and time distribution of 125I gas, contamination of foliage of the plants, accumulation and transfer of 125I fallen on the soil and entered into the plants from the roots of crops and vegetables, the time distribution of 125I in crops in water contaminated from 125I fallout, distribution, accumulation and transfer of 125I in chickens and rabbits which inhaled 125I gas or fed the fodder contaminated from 125I. The control measures of contamination in agroenvironment from 125I were discussed. (7 refs., 20 figs., 29 tabs.)

  5. Development of procedure using plasma welding process to produce 125I seeds

    International Nuclear Information System (INIS)

    The prostate cancer, which is the second cause of death by cancer in men, overcome only by lung cancer, is a problem of public health in Brazil. Brachytherapy is among the possible available treatments for prostate cancer, in which small seeds containing 125I radioisotope are implanted in the prostate. The seed consists of a titanium sealed capsule with 0.8 mm external diameter and 4.5 mm length, containing a central silver wire with adsorbed 125I. The plasma arc welding is one of the viable techniques for the sealing process. The equipment used in this technique is less costly than in other processes. The main objective of this work was the development and the validation of the welding procedure using plasma welding process and the elaboration of a sealing routine according to Good Manufacturing Practices. The development of this work has presented the following phases: cut and cleaning of the titanium material, determination of the welding parameters, development of a device for holding the titanium tube during the welding process, validation of sealed sources according to ISO 2919 Sealed Radioactive Sources - General Requirements and Classification, leakage test according to ISO 9978 Sealed Radioactive Sources - Leakage Test Methods and metallographic assays. The developed procedure, to seal 125I seeds using plasma welding process, has shown to be efficient, satisfying all the established requirements of ISO 2919. The results obtained in this work have given the possibility to establish a routine production process according to the orientations presented in resolution RDC number 59 - Good Manufacturing Practices do Medical Products of the ANVISA - Brazilian Nacional Agency of Sanitary Surveillance. (author)

  6. Evaluating the Phoenix Definition of Biochemical Failure After 125I Prostate Brachytherapy: Can PSA Kinetics Distinguish PSA Failures From PSA Bounces?

    International Nuclear Information System (INIS)

    Purpose: To evaluate the prostate-specific antigen (PSA) kinetics of PSA failure (PSAf) and PSA bounce (PSAb) after permanent 125I prostate brachytherapy (PB). Methods and Materials: The study included 1,006 consecutive low and 'low tier' intermediate-risk patients treated with 125I PB, with a potential minimum follow-up of 4 years. Patients who met the Phoenix definition of biochemical failure (nadir + 2 ng/mL-1) were identified. If the PSA subsequently fell to ?0.5 ng/mL-1without intervention, this was considered a PSAb. All others were scored as true PSAf. Patient, tumor and dosimetric characteristics were compared between groups using the chi-square test and analysis of variance to evaluate factors associated with PSAf or PSAb. Results: Median follow-up was 54 months. Of the 1,006 men, 57 patients triggered the Phoenix definition of PSA failure, 32 (56%) were true PSAf, and 25 PSAb (44%). The median time to trigger nadir + 2 was 20.6 months (range, 6-36) vs. 49 mo (range, 12-83) for PSAb vs. PSAf groups (p < 0.001). The PSAb patients were significantly younger (p < 0.0001), had shorter time to reach the nadir (median 6 vs. 11.5 months, p = 0.001) and had a shorter PSA doubling time (p = 0.05). Men younger than age 70 who trigger nadir +2 PSA failure within 38 months of implant have an 80% likelihood of having PSAb and 20% chance of PSAf. Conclusions: With adequate follow-up, 44% of PSA failures by the Phoenix definition in our cohort were found to be benign PSA bounces. Our study reinforces the need for adequate follow-up when reporting PB PSA outcomes, to ensure accurate estimates of treatment efficacy and to avoid unnecessary secondary interventions.

  7. Use of brachytherapy with permanent implants of iodine-125 in localized prostate cancer

    International Nuclear Information System (INIS)

    Approximately 15,000 cases of early stage prostate cancer T1 and T2 are diagnosed every year in France by testing for PSA and performing prostatic biopsies. The treatment of these localized forms is based in most cases on radical prostatectomy or nn external beam radiotherapy. Although the ontological results obtained by these two therapeutic methods are satisfactory and equivalent in the long term, the side effects can be important. For a number of years, trans-perineal brachytherapy using permanent implants of iodine -125 or palladium-103 has proved itself as an alternative therapy with equivalent medium to long-term results. The low urinary, digestive and sexual side effects of prostate brachytherapy are important reasons for the enthusiasm among patients and the medical community for this therapy and the growing number of applications and centres which practice it. In September 1998 we started the prostate brachytherapy programmes- in Marseilles with close collaboration between the department of urology of the Hopital Salvator, and the departments of radiotherapy, medical imaging and medical physics of the Institut Paoli-Calmettes. To date, around 250 patients with localized adenocarcinoma of the prostate have benefited from this alternative therapy in our centre. Preliminary results, with a 3 year-follow-up, are comparable to results published in the literature by pioneer teams. (authors)

  8. Intercomparison of ionisation chamber measurements from 125I seeds

    International Nuclear Information System (INIS)

    The reference air kerma rates of a set of individual 125I seeds were calculated from current measurements of a calibrated re-entrant ionisation chamber. Single seeds were distributed to seven Australian brachytherapy centres for the same measurement with the user's instrumentation. Results are expressed as the ratio of the reference air kerma rate measured by the Australian Nuclear Science and Technology Organisation (ANSTO) to the reference air kerma rate measured at the centre. The intercomparison ratios of all participants were within ±5% of unity

  9. Particle-rotor-model calculations in 125I

    Indian Academy of Sciences (India)

    Hariprakash Sharma; B Sethi; P Banerjee; Ranjana Goswami; R K Bhandari; Jahan Singh

    2001-07-01

    Recent experimental data on 125I has revealed several interesting structural features. These include the observation of a three quasiparticle band, prolate and oblate deformed bands, signature inversion in the yrast positive-parity band and identi?cation of the unfavoured $\\pi h_{11/2}$ band showing very large signature splitting. In the present work, particle-rotor-model calculations have been performed for the $\\pi h_{11/2}$ band, using an axially symmetric deformed Nilsson potential. The calculations reproduce the experimental results well and predict a moderate prolate quadrupole deformation of about 0.2 for the band.

  10. Radio synthesis and in vivo evaluation of two ?7 nAChRs radioligands. [125I]CAIPE and [125I]IPPU

    International Nuclear Information System (INIS)

    The radio synthesis and in vivo evaluation of two ?7 nAChRs radioligands [125I]CAIPE and [125I]IPPU were reported. They were obtained from their tributyltin precursors with high radio chemical yields ([90 %) and good radio chemical purities ([95 %). Biodistribution and blockade studies of [125I]CAIPE showed that the accumulation of radioactivity in the mouse brain was specific and selective. (author)

  11. Radioactive labelling with 125 I of infectious pancreatic necrosis virus

    International Nuclear Information System (INIS)

    In order to understand the interaction between a cellular receptor and a ligand the photochemical crosslinking method has been widely used. This method has been utilized as an approach to determine the presence or absence of virus receptors in susceptible cells. Successful detection of crosslinks is achieved if one of the components, in the crosslinked product, has been radioactively labeled. The incorporation of a radioactive isotope, in the virus-receptor complex, enables the identification of the receptor. To undertake this study in the future, in this communication the radioactive labeling of virus particles is presented. The infectious necrosis pancreatic virus (IPN virus) was the chosen moiety to be in vitro labeled with 125 I using a direct method. Three oxidizing agents were used in the iodination procedure for comparison: an enzyme, lactoperoxidase and two chemical reagents, N-Chloro-benceno-sulfonamide (Iodo-Beads) and 1,3,4,6-Tetra chloro-3a,6a-diphenyl glycouril (Iodo-Gen). The results are analysed to select the method which guarantee the incorporation of 125 I in the viral capsid protein, while preserving its full infectivity. (author)

  12. 125I iothalamate an ideal marker for glomerular filtration

    International Nuclear Information System (INIS)

    The triiodinated angiographic contrast medium, iothalamate (usually labelled 125I), has been used extensively as a marker for glomerular filtration. The authors have studied the renal handling of 125I iothalamate (IOT) in vivo and in vitro in several species. In renal cortical slices from chicken, rabbit, rat, and monkey, the tissue-to-medium ratio of IOT was twice that of 51Cr-EDTA (EDTA) at 37 degrees C; a difference that was abolished at 0 degree C and markedly reduced by added o-iodohippurate or iodipamide. In five chickens the steady-state renal clearance of IOT (CIOT) was twice that of EDTA (CEDTA) or 3H inulin (C1); a difference that was abolished by administration of 100 mg/kg/hr of novobiocin, an organic anion transport inhibitor. CEDTA was similar to C1 before as well as after transport inhibition. Utilizing the Sperber technique the mean apparent tubular excretion fraction (ATEF) of IOT was 8%, while that of EDTA was 1%. After novobiocin coinfusion (new steady-state) ATEFIOT was significantly reduced and not different from that of EDTA (-1%). In the same animals the total urinary recovery of IOT was 84 and 57% before and after novobiocin, respectively, while corresponding values for EDTA was unchanged by the inhibitor. In seven rats the renal extraction of IOT was reduced from 29 to 17% by coinfusion of probenecid (5 mg/kg/hr). Corresponding extractions were 82 to 34% and 22% (unchanged) for PAH and EDTA, respectively

  13. CT guided embedding of 125I by puncturing tissue through the cutis in patients with metastatic lung tumors

    International Nuclear Information System (INIS)

    Objective: To explore the clinical application and safety of treatment of percutaneous radioactive 125I seed implantation treatment in lung metastases under CT guidance. Methods: Twenty-seven lung metastatic malignancy cases (67 nodules) were studied. Eighteen cases (46 nodules) were hepatic cancer, 4 cases (9 nodules) were prostate cancer, and 5 cases (12 nodules) were breast carcinoma. Diameters of lung nodules ranged from 0.5 cm to 4.0 cm with an average diameter of 2.1 cm. 125I seeds were embedded under CT guidance, using 2 to 33 particles/nodule with an activity of 18.5 to 29.6 MBq/grain for each particle. Tumor matched peripheral dose was 90-120 Gy. Postoperative validation and quality evaluation followed. Results: Four months later, 24 nodules showed CR, 30 showed PR, 5 showed NC and 8 showed PD. The total effective rate was 80.6% (54/67). In the course of treatment, 11 patients had pneumothorax, 3 had heavy lung compression and 4 had hemoptysis. All conditions were improved by pleural puncture or under close follow-up observation. Conclusion: 125I seed implantation is an effective and safe technique in treatment of metastatic lung tumors under CT guidance. (authors)

  14. [B1-125I-desaminotyrosine]-insulin - A novel homogeneous insulin tracer

    International Nuclear Information System (INIS)

    [B1-125I-desaminotyrosine]-insulin (125I-MII) was prepared with high specific activities (420 Ci/mmole) by exchanging B1-phenylalanine for 125I-p-hydroxyphenyl-propionic acid N-hydroxysuccinimide ester (Bolton-Hunter reagent). Overall radiochemical yields were about 8%. Analytical quality control and purification were performed by means of radio high pressure liquid chromatography. The radiochemical purity of 125I-MII was >99%, and the immunoprecipitability was 97%. (author)

  15. Preliminary research of tissue heterogeneity correction for dose distribution of 125I brachytherapy source

    International Nuclear Information System (INIS)

    Tissue heterogeneity is commonly observed in clinical brachytherapy source implants. In some cases, an obvious variance in dose distribution will be caused by application of the AAPM recommended formulas, which are only valid for a homogeneous medium. By taking soft tissue as the base and considering adipose, air and bone as the separate interlayers, an evaluation model is established and dose correction formulas are derived for a single 125I source in this study. The applicability of correction formulas is validated at different interlayer thicknesses and angles by Monte Carlo (MCNP 4C) simulations. The results show fairly good agreement between correction formulas and MC simulations with overall maximum variances of 1.62±0.06, 5.93±0.23, and 8.41±0.33% for adipose, air, and bone, respectively. (author)

  16. Monte carlo simulation of dosimetric parameters for the model 6711 125I brachytherapy source

    International Nuclear Information System (INIS)

    The ?-radioactive seed brachytherapy source has been widely employed in the implantation therapy for the prostatic carcinoma and the ophthalmic lesions.In this study the dosimetric parameters for characterization of a low-energy interstitial brachytherapy source 125I were calculated according to dose calculation formalism recommended by AAPM TG-43U1. For data processing, a 0.28 cm active length was used for the geometry function. The dosimetry parameter air-Kerma strength, dose rate constant, radial dose function and anisotropy function were estimated by means of the EGS5 Monte Carlo code. The results obtained from this study are in good agreement with the corresponding values recommended by TG-43U1 and with the data reported by Dolan, et al. (authors)

  17. Dosimetric characterization of the GammaClip™169Yb low dose rate permanent implant brachytherapy source for the treatment of nonsmall cell lung cancer postwedge resection

    International Nuclear Information System (INIS)

    Purpose: A novel 169Yb low dose rate permanent implant brachytherapy source, the GammaClip™, was developed by Source Production and Equipment Co. (New Orleans, LA) which is designed similar to a surgical staple while delivering therapeutic radiation. In this report, the brachytherapy source was characterized in terms of “Dose calculation for photon-emitting brachytherapy sources with average energy higher than 50 keV: Report of the AAPM and ESTRO” by Perez-Calatayud et al. [Med. Phys. 39, 2904–2929 (2012)] using the updated AAPM Task Group Report No. 43 formalism.Methods: Monte Carlo calculations were performed using Monte Carlo N-Particle 5, version 1.6 in water and air, the in-air photon spectrum filtered to remove photon energies below 10 keV in accordance with TG-43U1 recommendations and previously reviewed 169Yb energy cutoff levels [D. C. Medich, M. A. Tries, and J. M. Munro, “Monte Carlo characterization of an Ytterbium-169 high dose rate brachytherapy source with analysis of statistical uncertainty,” Med. Phys. 33, 163–172 (2006)]. TG-43U1 dosimetric data, including SK, D-dot (r,?), ?, gL(r), F(r, ?), ?an(r), and ?an were calculated along with their statistical uncertainties. Since the source is not axially symmetric, an additional set of calculations were performed to assess the resulting axial anisotropy.Results: The brachytherapy source's dose rate constant was calculated to be (1.22 ± 0.03) cGy h?1 U?1. The uncertainty in the dose to water calculations, D-dot (r,?), was determined to be 2.5%, dominated by the uncertainties in the cross sections. The anisotropy constant, ?an, was calculated to be 0.960 ± 0.011 and was obtained by integrating the anisotropy factor between 1 and 10 cm using a weighting factor proportional to r?2. The radial dose function was calculated at distances between 0.5 and 12 cm, with a maximum value of 1.20 at 5.15 ± 0.03 cm. Radial dose values were fit to a fifth order polynomial and dual exponential regression. Since the source is not axially symmetric, angular Monte Carlo calculations were performed at 1 cm which determined that the maximum azimuthal anisotropy was less than 8%.Conclusions: With a higher photon energy, shorter half-life and higher initial dose rate 169Yb is an interesting alternative to 125I for the treatment of nonsmall cell lung cancer

  18. Brain necrosis after permanent low-activity iodine-125 implants. Case report and review of toxicity from focal radiation

    Energy Technology Data Exchange (ETDEWEB)

    Bampoe, J.; Nag, S.; Bernstein, M. [Toronto Western Hospital, ON (Canada); Leung, P.; Laperriere, N.

    2000-07-01

    Focal irradiation has emerged as a useful modality in the management of malignant brain tumors. Its main limitation is radiation necrosis. We report on the radiation dose distribution in the cerebellum of a patient who developed imaging and autopsy diagnosis of radiation necrosis after permanent iodine-125 implants for a solitary osseous plasmacytoma of her left occipital condyle. A 55-year-old woman initially presented with neck and occipital pain and a lytic lesion of her left occipital condyle. A cytological diagnosis of solitary osseous plasmacytoma was made by transpharyngeal needle biopsy. After an initial course of external beam radiation, the patient required further treatment with systemic chemotherapy 21 months later for clinical and radiographic progression of her disease. She ultimately required subtotal surgical resection of an ana-plastic plasmacytoma with intracranial extension. Permanent low-activity iodine-125 seeds were implanted in the tumor cavity. Satisfactory local control was achieved. However, clinical and imaging signs of radiation damage appeared 28 months after iodine-125 seed implantation. Progressive systemic myeloma led to her death 11 years after presentation and 9 years after seed implantation. Radiation dose distribution is described, with a discussion of toxicity from focal radiation dose escalation. (author)

  19. An algorithm for efficient metal artifact reductions in permanent seed implants

    International Nuclear Information System (INIS)

    Purpose: In permanent seed implants, 60 to more than 100 small metal capsules are inserted in the prostate, creating artifacts in x-ray computed tomography (CT) imaging. The goal of this work is to develop an automatic method for metal artifact reduction (MAR) from small objects such as brachytherapy seeds for clinical applications. Methods: The approach for MAR is based on the interpolation of missing projections by directly using raw helical CT data (sinogram). First, an initial image is reconstructed from the raw CT data. Then, the metal objects segmented from the reconstructed image are reprojected back into the sinogram space to produce a metal-only sinogram. The Steger method is used to determine precisely the position and edges of the seed traces in the raw CT data. By combining the use of Steger detection and reprojections, the missing projections are detected and replaced by interpolation of non-missing neighboring projections. Results: In both phantom experiments and patient studies, the missing projections have been detected successfully and the artifacts caused by metallic objects have been substantially reduced. The performance of the algorithm has been quantified by comparing the uniformity between the uncorrected and the corrected phantom images. The results of the artifact reduction algorithm are indistinguishable from the true background value. Conclusions: An efficient algorithm for MAR in seed brachytherapy was developed. The test results obtained using raw helical CT data for both phantom and clinical cases have demonstrated that the proposed MAR method is capable of accurately detecting and correcting artifacts caused by a large number of very small metal objects (seeds) in sinogram space. This should enable a more accurate use of advanced brachytherapy dose calculations, such as Monte Carlo simulations.

  20. An algorithm for efficient metal artifact reductions in permanent seed implants

    Energy Technology Data Exchange (ETDEWEB)

    Xu Chen; Verhaegen, Frank; Laurendeau, Denis; Enger, Shirin A.; Beaulieu, Luc [Departement de Radio-Oncologie et Centre de Recherche en Cancerologie, Universite Laval, Centre Hospitalier Universitaire de Quebec, 11 Cote du Palais, Quebec, Quebec G1R 2J6 (Canada) and Departement de Genie Electrique et Genie Informatique, Laboratoire de Vision et Systemes Numeriques, Universite Laval, Quebec, Quebec G1K 7P4 (Canada); Department of Radiation Oncology (MAASTRO), GROW-School for Oncology and Developmental Biology, Maastricht University Medical Center, Maastricht 6201 BN (Netherlands) and Oncology Department, Montreal General Hospital, McGill University, 1650 Cedar Avenue, Montreal, Quebec H3G 1A4 (Canada); Departement de Genie Electrique et Genie Informatique, Laboratoire de Vision et Systemes Numeriques, Universite Laval, Quebec, Quebec G1K 7P4 (Canada); Departement de Radio-Oncologie et Centre de Recherche en Cancerologie, Universite Laval, Centre Hospitalier Universitaire de Quebec, 11 Co circumflex te du Palais, Quebec, Quebec G1R 2J6 (Canada); Departement de Radio-Oncologie et Centre de Recherche en Cancerologie, Universite Laval, Centre Hospitalier Universitaire de Quebec, 11 Cote du Palais, Quebec, Quebec G1R 2J6 (Canada) and Departement de Physique, de Genie Physique et d' Optique, Universite Laval, Quebec, Quebec G1K 7P4 (Canada)

    2011-01-15

    Purpose: In permanent seed implants, 60 to more than 100 small metal capsules are inserted in the prostate, creating artifacts in x-ray computed tomography (CT) imaging. The goal of this work is to develop an automatic method for metal artifact reduction (MAR) from small objects such as brachytherapy seeds for clinical applications. Methods: The approach for MAR is based on the interpolation of missing projections by directly using raw helical CT data (sinogram). First, an initial image is reconstructed from the raw CT data. Then, the metal objects segmented from the reconstructed image are reprojected back into the sinogram space to produce a metal-only sinogram. The Steger method is used to determine precisely the position and edges of the seed traces in the raw CT data. By combining the use of Steger detection and reprojections, the missing projections are detected and replaced by interpolation of non-missing neighboring projections. Results: In both phantom experiments and patient studies, the missing projections have been detected successfully and the artifacts caused by metallic objects have been substantially reduced. The performance of the algorithm has been quantified by comparing the uniformity between the uncorrected and the corrected phantom images. The results of the artifact reduction algorithm are indistinguishable from the true background value. Conclusions: An efficient algorithm for MAR in seed brachytherapy was developed. The test results obtained using raw helical CT data for both phantom and clinical cases have demonstrated that the proposed MAR method is capable of accurately detecting and correcting artifacts caused by a large number of very small metal objects (seeds) in sinogram space. This should enable a more accurate use of advanced brachytherapy dose calculations, such as Monte Carlo simulations.

  1. Chemical Species and Content Analysis of 125I in Bok-choy and Ipomoea Aquatica Forsk

    International Nuclear Information System (INIS)

    Iodine has been long known as an indispensable element in the synthesis of thyroid hormones. Severe iodine deficiency in diet leads to iodine deficiency disorders in humans. An isotope tracer experiment was carried out to study the chemical species and content analysis of 125I absorbed by the Bok-choy and Ipomoea Aquatica Forsk. The results showed that inorganic 125I, organic 125I and residual 125I have been detected in Bok-choy and Ipomoea Aquatica Forsk. In Bok-choy,the inorganic 125I content is the most which up to 42.48%, and except for residual 125I the organic 125I content is taken up to 7.91%. But in Ipomoea Aquatica Forsk, the content of 125I ranks as residual 125I > the inorganic 125I > organic 125I followed by 64.97%, 28.36% and 6.66%. The consists of inorganic 125I is I-, IO3-and I2 in both Bok-choy and Ipomoea Aquatica Forsk, and I-is the main chemical species. The protein-125I was the main form of organic iodine which respectively amounts to 22.43% and 8.68% of total iodine, the content of amylose-125I was the least which was 0.78% and 0.40% in both Bok-choy and Ipomoea Aquatica Forsk, and the content of the nucleic acid-125I is between them. The results showed that Bok-choy and Ipomoea Aquatica Forsk can enriched Iodine in environment. so, they could be cultivated as iodine vegetable. (authors)

  2. Solid phase 125I labelled radioimmunoassay for spermidine

    International Nuclear Information System (INIS)

    Using 125I labelled monoclonal antibody against spermidine and solid phase antigen spermidine-bovine serum albumin conjugate, the radioimmunoassay for spermidine was developed. The sensitivity of this method was about 8 times higher than that of liquid phase 14C labelled spermidine radioimmunoassay, reaching detection limit of 10 ng/ml (0.5 ng/tube). The working range of standard curve was 0-105 ng/ml. The new method was suitable for spermidine measurements in saliva, stomach fluid, and cerebrospinal fluid. The coefficients of variation (CV) of within and between-assay were 4% and 13%, respectively. Preliminary clinical measurements showed that the spermidine levels in saliva of cancer patients and in cerebrospinal fluid of leukemia patients were significantly elevated

  3. IB intensities in EC decay of 125I

    International Nuclear Information System (INIS)

    The internal Bremsstrahlung (IB) spectrum from the allowed electron capture (e.c.) decay of 125I level of 125Te was studied using a 2x2 inch NaI (Tl) scintillation detector and a PC based multichannel analyser. The unfolding method was applied for deriving true IB spectrum; and a modified Jauch's plot was drawn in view of intense 2p- capture admixed with 1 s. Through an iteration technique, the 1s end-point energy was determined as 80± 1.6 keV. The intensities evaluated on the basis of Glauber and Martin (GM) and Intemann theories coincided with the experimental intensities for most part of the IB spectrum. (author). 15 refs., 2 figs., 1 tab

  4. Consumption of 125I labelled fibrinogen in normal subjects

    International Nuclear Information System (INIS)

    The metabolism of iodine-125 labeled human fibrinogen is studied by using three different sets of the radiopharmaceutical (0.9, 1.3 and 1.84 iodine atoms/fibrinogen molecule ratios) in 19 normal subjects. An aliquot of 40 ?Ci of fibrinogem-125I is injected in each subject, on normal dietary conditions and blood samples are withdrawn at 30, 60, 180, 36 and 720 minutes after the injection and, thereafter, one daily sample during 10 days. The compartmental distribution of the tracer is defined by plotting plasma and serum sample counts on a semilogarithmic graph paper. A rapid phase and 3 compartments are obtained. A 'rapid' consumption half-life and a 'real' consumption half-life are defined. The fibrinogen clottability is followed up to the last blood sample by checking the ratios of serum and plasma radioactivities

  5. Measurement of mucosal blood flow by assay of absorption of 125I from the intestinal lumen

    International Nuclear Information System (INIS)

    A method which utilized the absorption of 125I as a measure of intestinal mucosal blood flow was developed. In the pentobarbital anesthetized dog a segment of mid-jejunum was isolated from adjacent vasculature and perfused with 125I solution. Superior mesenteric artery flow, blood flow to the isolated segment of intestine and 125I absorption were measured. Changes in 125I absorption were found to correlated closely with changes in blood flow (r . 0.95). Using an autoradiographic technique 125I absorption was found to be localized to the intestinal mucosa

  6. Pharmacokinetics and organ distribution of 125I-aprindine

    International Nuclear Information System (INIS)

    An attempt was made to label aprindine hydrochloride with I-125 by means of an exchange reaction. Organ distribution was determined in 10 rats where radioactivity was measured in the lung, heart, liver, kidney, spleen, brain, transverse muscle tissue and bone sections 5, 10, 30 and 60 min following i.v. injection. The high organ concentration was found in the lung, and also the maximum ratio organ: blood radioactivity was found for this organ. Whole body activity measurements revealed a half-life of nearly 6 hr. Excretion occurred primarily via the faeces. The pharmacokinetic properties of 14C- and 125I-aprindine hydrochloride do not therefore differ significantly. A whole body scintiscanning was carried out on an additional 12 rats and 6 rabbits. This revealed a marked enrichment in the lung compared to other organs in the time period 5 to 10 min. An image of relatively good quality was obtained compared to that of conventional perfusion scintiscanning with 131I-HSA. It is assumed that 125I-aprindine hydrochloride is concentrated in the lung parenchyma and is therefore largely unaffected by the immediate perfusion conditions. This is also confirmed in preliminary studies with 131I-aprindine in the scintiscanning of rabbits where voids of pneumonia activity are shown in the aprindine scintigram whereas with the perfusion method these are not. As expected, the reverse was shown to be true following experimental pulmonary embolism where voids were seen in the perfusion scintigram whilst the 131I-aprindine scintigram revealed hardly any areas of drops in activity. These properties possibly offer an improved diagnostic procedure for differentiating between pneumonia and lung infarct by combination with perfusion scintiscanning. (orig./MG)

  7. Studies on the adsorption of 125I on bromide coated silver rods for the preparation of 125I-seeds for brachytherapy applications

    International Nuclear Information System (INIS)

    This paper describes a method for the preparation of 125I brachytherapy sources. The process consist of surface oxidation of a silver rods [0.5 mm (?) x 3 mm (1)], formation of a thin silver bromide over layer and finally replacement of bromide ions by 125I- ions. The effect of various parameters such as 125I feed activity, iodide carrier concentration and reaction time were examined and optimized for maximum impregnation of 125I activity on the substrate. Sources containing 74-111 MBq (2-3 mCi) 125I on a silver matrix could be prepared and encapsulated in titanium capsules [0.8 mm (?) x 4.75 mm (1)] using Nd: YAG laser. Quality assurance tests to ensure nonleachability, uniform distribution of activity and leak tightness that are necessary before application were evaluated. (author)

  8. Purification of 125I-vasoactive intestinal peptide by reverse-phase HPLC

    International Nuclear Information System (INIS)

    VIP was labeled with sodium [125I]iodide, and 125I-VIP was purified by reverse-phase high performance liquid chromatography. Optimal separations of 125I-VIP and unlabeled VIP were obtained using two C18- Novapak columns in series and a gradient of acetonitrile in triethylamine phosphate for elution. The specific activity of the 125I-VIP was 1.99 +/- 0.21 Ci/mumole, approaching the maximum specific activity of monoiodinated VIP (2.26 Ci/mumole). Radioimmunoassay and radioreceptorassay for VIP were more sensitive (2.6-fold, and 2.5-fold, respectively) using 125I-VIP purified by HPLC compared to 125I-VIP obtained from an open-end cellulose column. These results demonstrate the advantage of preparing purified 125I-VIP by HPLC for the accurate assay of VIP and VIP-receptors in tissues and biological fluids

  9. Metabolism and placental transfer of /sup 125/I-proinsulin and /sup 125/I-tyrosylated C-peptide in the pregnant rhesus monkey

    Energy Technology Data Exchange (ETDEWEB)

    Gruppuso, P.A.; Susa, J.B.; Sehgal, P.; Frank, B.; Schwartz, R.

    1987-10-01

    /sup 125/I-Proinsulin or /sup 125/I-tyrosylated-C-peptide (/sup 125/I-tyr-CP) was administered to pregnant Rhesus monkeys by bolus followed by constant infusion to examine placental transfer of these peptides. At the end of each infusion, fetuses were exsanguinated in situ via the umbilical vein. The bolus-constant infusion technique produced a steady state in maternal plasma of immunoprecipitable label, measured using excess insulin or C-peptide antiserum. In animals infused with /sup 125/I-proinsulin, analysis of umbilical venous plasma revealed no apparent transfer to the fetus of immunoprecipitable label. In animals infused with /sup 125/I-tyr-CP, 3-13% of the umbilical venous plasma radioactivity was immunoprecipitable, representing 1.4-5.8% of the immunoprecipitable radioactivity in maternal plasma at delivery. Gel filtration chromatography of umbilical venous plasma revealed that the immunoprecipitated moiety was a fragment of /sup 125/I-tyr-CP. Analysis of maternal plasma showed that the predominant peak of radioactivity represented intact C-peptide. A peak corresponding to the fetal immunoprecipitable peak was also present. Analysis of simultaneous maternal arterial and uterine vein plasma samples showed that degradation of /sup 125/I-tyr-CP occurred across the uterus. Studies in one nonpregnant and three postpartum animals indicated that pregnancy increased the rate of metabolism of /sup 125/I-tyr-CP. When /sup 125/I-tyr-CP was incubated with trophoblastic cells in culture, degradation to a species corresponding on gel filtration to the immunoprecipitable fetal metabolite was found. We conclude that proinsulin, like insulin, does not traverse the placenta. Immunoreactive fragments of C-peptide do cross, however, and pregnancy alters the metabolism of /sup 125/I-tyr-CP, probably owing to placental degradation.

  10. Metabolism of (125I)tyramine cellobiose-labeled low density lipoproteins in squirrel monkeys

    International Nuclear Information System (INIS)

    Low density lipoproteins labeled with (125I)tyramine cellobiose ((125I)TC-LDL) were removed from the circulation of squirrel monkeys at a similar but slightly slower rate than LDLs labeled with 125I, (125I)hydroxypenyl propionic acid, or (3H)leucine. After the simultaneous injection of ((125I)TC-LDL) and (131I)LDL labeled with 131ICI, the 125I was also removed at a slightly slower rate than 131I. Most of the radioactivity was retained in tissues and not excreted during the 24 h after injection of (125I)TC-LDL. This finding supports the claim of Pittman et al. (18) that (125I)TC-LDL can be used to determine the irreversible uptake of LDL by different tissues. The liver cleared more LDL than any other organ, but the adrenals and ovaries were more active per gram. Trichloroacetic acid (TCA) precipitated more than 80% of the radioactivity in the tissues that had low 125I uptake, but only about 50% of the 125I in more active tissues (liver, adrenals, ovaries and spleen). Only a small percentage of 125I in urine and bile was TCA-precipitable. In the dual label experiment with (125I)TC-LDL and (131I)LDL there was a selective retention of 125I in samples from liver, spleen, adrenals, and perhaps testes, and an almost complete selectivity for 125I in bile and feces. The aortic intima plus inner media (AIM) cleared much less LDL than other tissues, but the uptake by the entire AIM was proportional to the cholesterol concentration and weight of the total AIM. There was, however, no correlation between either of the latter two measurements and the uptake of LDL per pram of AIM. (author)

  11. Prostate dose calculations for permanent implants using the MCNPX code and the Voxels phantom MAX

    Energy Technology Data Exchange (ETDEWEB)

    Reis Junior, Juraci Passos dos; Silva, Ademir Xavier da, E-mail: jjunior@con.ufrj.b, E-mail: Ademir@con.ufrj.b [Coordenacao dos Programas de Pos-Graduacao de Engenharia (COPPE/UFRJ), RJ (Brazil). Programa de Engenharia Nuclear; Facure, Alessandro N.S., E-mail: facure@cnen.gov.b [Comissao Nacional de Energia Nuclear (CNEN), Rio de Janeiro, RJ (Brazil)

    2010-07-01

    This paper presents the modeling of 80, 88 and 100 of {sup 125}I seeds, punctual and volumetric inserted into the phantom spherical volume representing the prostate and prostate phantom voxels MAX. Starting values of minimum and maximum activity, 0.27 mCi and 0.38 mCi, respectively, were simulated in the Monte Carlo code MCNPX in order to determine whether the final dose, according to the integration of the equation of decay at time t = 0 to t = {infinity} corresponds to the default value set by the AAPM 64 which is 144 Gy. The results showed that consider sources results in doses exceeding the percentage discrepancy of the default value of 200%, while volumetric consider sources result in doses close to 144 Gy. (author)

  12. Computational program of isodose and treatment planning system (TPS) for brachytherapy using 125I-seed-sources

    International Nuclear Information System (INIS)

    To reach the goals of a brachytherapy treatment, a guaranteed dose rate calculation as well as a treatment planning system (TPS) are absolutely needed. Therefore, a local computational program for isodose and TPS calculations has been developed. The program has been performed using Microsoft Visual Basic for Windows and its supporting tools based on dosimetry calculation models developed and updated by the Association of American Physicist in Medicine. The program was started from the dose rate calculation of the of 125I-seed-source assumed as a line source with 0.3 cm of active length. This program can display two dimensions-isodose contour of the single or poly 125I-seeds presented in the directions of lateral, anterior and caudal by changing the polar coordinate system (r, ?) into a Cartesian coordinate system (x,y). The dose rate at the distances of 1, 2, 3 and 4 cm from the center point as well as the effect of single-seed-source rotation can also be calculated. The entered data as well as the resulting calculation and the isodose contour presentation can be saved, quickly traced and redisplayed at any time necessarily. It was found that this computer program is in agree with the referenced data so it is hopefully able to assist physicians in the domestic implementation of 125I seeds implants for brachytherapy. (author)

  13. Microbial contamination detection at low levels by [125]I radiolabeling

    Science.gov (United States)

    Summers, David; Karouia, Fathi

    Contamination of mission spacecraft is an ongoing issue. A broad diversity of microorganisms have been detected in clean rooms where spacecraft are assembled. Some of which, depicted as oligotroph, are of special regard, as they are capable of colonizing inorganic surfaces like metal, and have been shown to be a concern for forward contamination of pristine celestial bodies. Currently, the NASA standard assay is the only approved assay intended for the enumeration of spores and heterotrophic microbial populations. However, culture-based microbial detection methods underestimate the viable microbial population. More recently, adenosine triphosphate (ATP) bioluminescence and limulus amebocyte lysate (LAL) assays, which employ measure-ments of selected metabolic products as a proxy of biomass, have been used successfully to circumvent the necessity of the growth of microorganisms in order to estimate the biodurdens associated with spacecraft assembly facility. However, these methods have limitation in the amount of cells that can be detected, i.e., 103 cells, and the type of microorganisms respec-tively. This work seeks to develop a new highly sensitive method for the determination of bioburdens (and the detection of microorganisms and life) that is independant of the type of organism while preserving a good turn-around time for analysis for planetary protection purposes. The assay is based on the detection of the organism's protein by labeling them by radioiodination, 125 I, of aromatic rings on tyrosine amino acids residues. Radiolabeling techniques are inherently sensitive and 125 I, in particular, benefits from a 60 day half-life, providing greater activity and signal per unit number of labels. Furthermore, microorganisms can contain over 50% of protein by dry weight. Thus, just one label per protein increases the sensitivity, compared to the ATP and LAL assays, by one and three orders of magnitude by using standard detection methods and the use of multiphoton detection (MPD), respectively. Therefore this assay enables the detection to lower levels than previously possible, down to single cells. The method has also applicability for testing returned samples hardware and for the testing sterilization methods as well as other Astrobiological applications. Future work could extend to species such as viruses and prions.

  14. Clinical research on the treatment effects of radioactive (125)I seeds interstitial brachytherapy on children with primary orbital rhabdomyosarcoma.

    Science.gov (United States)

    Ge, Xin; Ma, Jianmin; Dai, Haojie; Ren, Ling; Li, Quan; Shi, Jitong

    2014-09-01

    Rhabdomyosarcoma (RMS) is one of the most common primary orbital malignancies. However, orbital RMS is a very rare disease, especially in childhood, and the tumor has a high degree of malignancy and rapid development. The objective of the present study was to investigate the clinical treatment effects of radioactive (125)I seeds interstitial brachytherapy on children with primary orbital RMS, which may provide a new method for treating RMS in clinical applications. Radioactive (125)I seeds were used in the present study. Primary lesions from ten children with orbital RMS, including three male and seven female patients, were selected as the targeted areas. The activity, number and spatial location of the seeds were optimized and simulated by applying computer three-dimensional treatment planning system (TPS) software. The interstitial implantation of the radioactive (125)I seeds was conducted on children under general anesthesia according to the TPS simulation results. Quality verifications of the operation were conducted by orbital computed tomography and X-ray plain film at the early stage after operation, and the children were followed up. The patients were followed up by October 2012 with an average follow-up time of 57 ± 17.43 months and a median follow-up time of 55 months. Nine cases achieved complete remission, and one case achieved partial remission, resulting in a total efficiency and survival rate of 100.0 % (10/10). Most patients recovered after treatment or had no radiotherapy side effect after the operations, though 20.0 % of the patients (2/10) experienced corneal opacity, eyeball movement disorder, or loss of sight. Radioactive (125)I seeds interstitial brachytherapy was an effective treatment for children with primary orbital RMS. Results from this study may provide a new clinical approach for the treatment of child patients with primary orbital RMS. PMID:25092038

  15. Synthesis of [125I]iodoDPA-713: A new probe for imaging inflammation

    International Nuclear Information System (INIS)

    [125I]IodoDPA-713 [125I]1, which targets the translocator protein (TSPO, 18 kDa), was synthesized in seven steps from methyl-4-methoxybenzoate as a tool for quantification of inflammation in preclinical models. Preliminary in vitro autoradiography and in vivo small animal imaging were performed using [125I]1 in a neurotoxicant-treated rat and in a murine model of lung inflammation, respectively. The radiochemical yield of [125I]1 was 44 ± 6% with a specific radioactivity of 51.8 GBq/?mol (1400 mCi/?mol) and >99% radiochemical purity. Preliminary studies showed that [125I]1 demonstrated increased specific binding to TSPO in a neurotoxicant-treated rat and increased radiopharmaceutical uptake in the lungs of an experimental inflammation model of lung inflammation. Compound [125I]1 is a new, convenient probe for preclinical studies of TSPO activity.

  16. 125I-LSD: a high sensitivity ligand for serotonin receptors

    International Nuclear Information System (INIS)

    125I-labeled receptor ligands offer unique advantages over their 3H-labeled counterparts. Carrier-free 125I-labeled ligands can be synthesized with specific activities of up to 2170 Ci/mmol while (mono) tritium labeled ligands are limited to 29 Ci/mmol. Therefore, 125I-labeled ligands can be approximately 70-fold more sensitive than 3H-labeled ligands in detecting receptor sites. In addition, 125I-labeled ligands emit relatively energetic X-rays and ?-rays which are readily detected by gamma counting equipment. The authors report here the serotonergic binding properties of 125I-LSD the first reported 125I-labeled ligand for serotonin receptors. (Auth.)

  17. Minimally invasive implantation of an extracorporeal membrane oxygenation circuit used as a temporary left ventricular assist device: a new concept for bridging to permanent cardiac support.

    Science.gov (United States)

    Saito, Shunsuke; Fleischer, Bernhard; Maeß, Christoph; Baraki, Hassina; Kutschka, Ingo

    2015-03-01

    The implantation of cardiac assist devices is associated with poor outcome in patients with multiple organ failure and unknown neurologic status. Therefore, temporary left ventricular assist devices (LVAD) using, for example, extracorporeal centrifugal pumps may provide the chance to further evaluate the patient's clinical course and a potential qualification for implantable LVAD therapy. On the other hand, a main disadvantage of the temporary LVAD implantation is the need for redo surgery, increasing the risk of the final LVAD Implantation. To minimize this drawback of the temporary LVAD implantation, we implanted the temporary LVAD using a minimally invasive technique. The operation was done without cardiopulmonary bypass support, and the temporary LVAD was implanted through upper hemisternotomy and left anterior mini-thoracotomy. The patient recovered from multiple organ failure and was successfully bridged to a permanent LVAD therapy. PMID:25370719

  18. Intraperitoneal (125I) insulin absorption during intermittent and continuous peritoneal dialysis

    International Nuclear Information System (INIS)

    The authors have measured intraperitoneal (125I) insulin absorption during intermittent and continuous peritoneal dialysis in order to study the following: insulin regulation of blood glucose when administered continuously via dialysate during continuous ambulatory peritoneal dialysis (CAPD) versus when given intermittently and subcutaneously before CAPD; the degree of (125I) insulin retention in plastic CAPD bags, after complete drainage of the dialysis fluid; absorption of (125I) insulin from the dialysate in the peritoneal cavity of diabetic and non-diabetic patients. (Auth.)

  19. Production of seed source 125 I for treatment of eye and prostate cancer

    International Nuclear Information System (INIS)

    Brachytherapy sources was studied. A method was optimized to obtain 125 I on the palladium treated silver wires. The adsorption of palladium coated silver showed quantitative and consistent uptake (83 % ) of 125 I and exhibited low leach ability ( 0.06 % ) 125 I adsorption on palladium coated silver wires could be used as matrix for the preparation of interstitial source in eye and prostate cancer and also tumors of the head, neck, lung and pancreas

  20. Binding of in vivo administrated 125-I-triiodothyronine by the rat liver mitochondria

    International Nuclear Information System (INIS)

    In vivo administrated 125I-triiodothyronine (125I-T3) was bound by the rat liver mitochondria. About 10 % of hormone was bound with external mitochondrial membrane while the remaining part with matrix and inner mitochondrial membrane. The highest accumulation of 125I-T3 in mitochondria was observed 30 min after injection while in the whole liver homogenate the highest hormone accumulation appeared 15 min post injection. Mitochondrial binding sites have a great capacity for T3 which makes impossible estimation of the kinetic parameters of triiodothyronine-mitochondrium interaction by means of saturation and displacement of 125I-T3. (author)

  1. First report of a permanent breast 103Pd seed implant as adjuvant radiation treatment for early-stage breast cancer

    International Nuclear Information System (INIS)

    Purpose: A new technique of adjuvant partial breast irradiation using 103Pd permanent breast seed implants (PBSI) is presented. The procedure is performed in a single 1-hour session under local anesthesia. Methods and Materials: Patients referred to a single institution for adjuvant radiotherapy after lumpectomy for an infiltrating ductal carcinoma ?3 cm in diameter, surgical margin ?2 mm, no extensive in situ carcinoma, no lymphovascular invasion, and minimal or negative lymph node involvement were offered a PBSI. Results: Between May and December 2004, 31 eligible patients underwent CT scan and ultrasound simulations assessing PBSI feasibility. Fifteen were excluded because of feasibility issues, and 16 received PBSI. A minimal peripheral dose of 90 Gy was prescribed to the planning target volume corresponding to the clinical target volume identified on the CT scan plus a margin of 1 cm. The procedure was well tolerated; 56% of the patients reported no pain during the procedure, and 46% of the patients developed National Cancer Institute Common Toxicity Criteria Grade 1 acute reaction. None experienced toxicity Grade 2 or 3. Conclusions: Permanent breast seed implantation seems feasible and well tolerated on these preliminary clinical data and represents an ultimate step in the reduction of treatment fraction for partial breast irradiation

  2. The value of preoperative tests in the selection of blind patients for a permanent microelectronic implant.

    OpenAIRE

    Yanai, Douglas; Lakhanpal, Rohit R; Weiland, James D.; Mahadevappa, Manjunatha; Van Boemel, Gretchen; Fujii, Gildo Y; Greenberg, Robert; Caffey, Sean; de Juan, Eugene; Humayun, Mark S

    2003-01-01

    PURPOSE: To determine the best candidates (ie, those requiring lowest current levels delivered to the retina to elicit visual perceptions) for long-term implantation of a microelectronic retinal implant through a series of preoperative visual, psychophysical, and electrophysiological tests. METHODS: This study protocol was granted an investigational device exemption by the Food and Drug Administration and was approved by the institutional review board at the University of Southern California....

  3. Effects of lysosomal inhibitors on 125I-insulin and 125I-asialofetuin degradation by the isolated, perfused rat liver and isolated rat hepatocytes

    International Nuclear Information System (INIS)

    To further evaluate the role of the lysosomal system in insulin degradation, the authors have compared the effects of inhibitors of lysosomal function on the degradation of 125I-insulin with 125I-asialofetuin, a lysosomally targeted molecule, by the intact, perfused rat liver and the isolated rat hepatocyte. The inhibitors employed were chloroquine (125 microM), NH4Cl (10 mM), and leupeptin (50 micrograms/ml). In the intact, perfused liver the observed inhibition of 125I-asialofetuin degradation at 30 min was as follows: chloroquine, 38%; NH4Cl, 32%; and leupeptin, 86%. Chloroquine also inhibited 125I-insulin degradation in the intact, perfused liver (29%), but NH4Cl and leupeptin had no effect. Using the isolated hepatocyte, the observed values for inhibition of 125I-asialofetuin at 60 min were: chloroquine, 85%; NH4Cl, 76%; and leupeptin, 81%. Chloroquine produced a 28% inhibition of 125I-insulin degradation, while NH4Cl and leupeptin had no effect. Chloroquine and NH4Cl decreased cell-associated radioactivity when isolated hepatocytes were incubated with 125I-asialofetuin (leupeptin had no effect), whereas chloroquine caused a 107% increase in cell-associated radioactivity when 125I-insulin was added to the incubation media (NH4Cl and leupeptin had no effect). These results indicate that the effects of chloroquine on insulin degradation are an extralysosomal action and that lysosomes appear not to be involved in the physiologic degradation of the insulin molecule

  4. Preparation of 1-phenyl 3-methyl 4-nitro 5-125I-pyrazole (5-125I-MNPP) as a possible cannabinoid receptor imaging agent

    International Nuclear Information System (INIS)

    A rapid method for labelling of 1-phenyl 3-methyl 4-nitro 5-chloro pyrazole (5-Cl-MNPP) with radioactive iodide Na125I via 125I-for-Cl exchange has been reported. This method has been done in dry state (without catalyst and in presence of acetamide), in dimethyl formamide (DMF) as a solvent (without catalyst and in presence of tetrabutyl ammonium bromide (TBAB) as phase transfer catalyst (PTC)). In dry state, a trial to reduce the reaction temperature from 170 to 120 deg C for the reaction between 5-Cl-MNPP and Na125I in presence of acetamide as a molten medium was tested. Using some organic solvents such as ethanol, dimethyl sulfoxide (DMSO), acetonitrile, and DMF, it was found that DMF gave low radiochemical yield of 5-125I-MNPP (25%) within 30 min. However, the addition of 1 mg of TBAB to DMF increased the radiochemical yield of 5-125I-MNPP from 25 to 95 within 30 minutes. The product 5-125I-MNPP was purified by reverse phase, high performance liquid chromatography (HPLC), with radiochemical purity of greater than 98.0%. The biodistribution of 5-125I-MNPP was demonstrated in normal mice through intravenous injection in the tail vein. High uptake in the target organs equal to 2.5±0.22, 10.5±0.21, 4.3±0.27, 3.2±0.18 and 48.5±0.26 for brain, intestines, heart, kidneys and liver respectively was shown. This indicates that, 5-125I-MNPP can be freely penetrate the blood brain barrier (B.B.B.) and can be expected its usefulness in the quantitative determination of cannabinoid receptor in the brain. (author)

  5. A comparative study of 19-iodo cholesterol-125I 3-acetate and Na 125I in liquid scintillation measurements; Estudio comparativo del acetato de 19-iodocolesterol- -125I con Nal25I en medidas por centelleo liquido

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez Barquero, L.; Grau Malonda, A.; Los Arcos Merino, J. M.; Grau Carles, A.

    1994-07-01

    A comparative study of performance of 19-iodo cholesterol {sup 1}25I 3-acetate and sodium iodide samples labeled with 125I is presented for liquid scintillation counting measurements. Quench effect, count rate stability and spectral evolution of samples have been followed for several weeks in Toluene, Hisafe II, Instagel, Dioxane-naphthalene and Toluene-alcohol scintillators. Organic samples have negligible quench effect in the interval of I concentration of 0-90 {mu}g and inorganic samples only show a very small variation, lower than 12%, for Dioxane-naphthalene, in the same range of concentration. Satisfactory stability is obtained in general for both, organic and inorganic samples, but small counting losses, 0.03% for 19-iodocholesterol 1 I 3-acetate samples in Tolue ne-alcohol and 0 .04% for Na 125I samples in Dioxane-naphthalene and Toluene-alcohol, have been reported. (Author) 8 refs.

  6. Systemic administration of kainic acid induces selective time dependent decrease in [{sup 125}I]insulin-like growth factor I, [{sup 125}I]insulin-like growth factor II and [{sup 125}I]insulin receptor binding sites in adult rat hippocampal formation

    Energy Technology Data Exchange (ETDEWEB)

    Quirion, R. [Department of Pharmacology and Therapeutics, McGill University, Montreal (Canada); Chabot, J.-G.; Dore, S. [Douglas Hospital Research Center, Department of Psychiatry, McGill University, Montreal (Canada); Seto, D. [Department of Pharmacology and Therapeutics, McGill University, Montreal (Canada); Kar, S. [Douglas Hospital Research Center, Department of Psychiatry, McGill University, Montreal (Canada)

    1997-08-11

    Administration of kainic acid evokes acute seizure in hippocampal pathways that results in a complex sequence of functional and structural alterations resembling human temporal lobe epilepsy. The structural alterations induced by kainic acid include selective loss of neurones in CA1-CA3 subfields and the hilar region of the dentate gyrus followed by sprouting and permanent reorganization of the synaptic connections of the mossy fibre pathways. Although the neuronal degeneration and process of reactive synaptogenesis have been extensively studied, at present little is known about means to prevent pathological conditions leading to kainate-induced cell death. In the present study, to address the role of insulin-like growth factors I and II, and insulin in neuronal survival as well as synaptic reorganization following kainate-induced seizure, the time course alterations of the corresponding receptors were evaluated. Additionally, using histological preparations, the temporal profile of neuronal degeneration and hypertrophy of resident astroglial cells were also studied. [{sup 125}I]Insulin-like growth factor I binding was found to be decreased transiently in almost all regions of the hippocampal formation at 12 h following treatment with kainic acid. The dentate hilar region however, exhibited protracted decreases in [{sup 125}I]insulin-like growth factor I receptor sites throughout (i.e. 30 days) the study. [{sup 125}I]Insulin-like growth factor II receptor binding sites in the hippocampal formation were found to be differentially altered following systemic administration of kainic acid. A significant decrease in [{sup 125}I]insulin-like growth factor II receptor sites was observed in CA1 subfield and the pyramidal cell layer of the Ammon's horn at all time points studied whereas the hilar region and the stratum radiatum did not exhibit alteration at any time. A kainate-induced decrease in [{sup 125}I]insulin receptor binding was noted at all time points in the molecular layer of the dentate gyrus whereas binding in CA1-CA3 subfields and discrete layers of the Ammon's horn was found to be affected only after 12 h of treatment. These results, when analysed with reference to the observed histological changes and established neurotrophic/protective roles of insulin-like growth factors and insulin, suggest possible involvement of these growth factors in the cascade of neurotrophic events that is associated with the reorganization of the hippocampal formation observed following kainate-induced seizures. (Copyright (c) 1997 Elsevier Science B.V., Amsterdam. All rights reserved.)

  7. Monte Carlo radiation dose simulations and dosimetric comparison of the model 6711 and 9011 125I brachytherapy sources

    International Nuclear Information System (INIS)

    Smaller diameter brachytherapy seeds for permanent interstitial implantation allow for use of smaller diameter implant needles. The use of smaller diameter needles may provide a lower incidence of healthy-tissue complications. This study determines the brachytherapy dosimetry parameters for the smaller diameter source (model 9011) and comments on the dosimetric comparison between this new source and the conventional brachytherapy seed (model 6711).

  8. Quality control of 125I-labelled fibrinogen of various species

    International Nuclear Information System (INIS)

    The modified chloramine-T method used for radioiodination of human, rat, and bovine fibrinogen guaranteed mild labelling conditions and a satisfactory labelling efficiency. The quality of the human, rat, and bovine 125I-fibrinogen preparations obtained met the requirements with respect to clottability, low content of 125I-labelled iodide as well as in vitro and in vivo stability. (author)

  9. Digital monitor of 125I in thyroid glands of human being

    International Nuclear Information System (INIS)

    A new digital monitor of 125I in thyroid glands is described. This instrument is used to measure the activity of 125I in thyroid glands of human being directly, rapidly, and accurately. Furthermore, it can calculate and display the intake, committed dose equivalent and committed effective dose equivalent

  10. Preparation, purification and characterization of 125I-glucagon used for radioimmunoassay

    International Nuclear Information System (INIS)

    A method for the radioactive labelling of glucagon with Na125I with the help of chloramine T for the use in radioimmunoassay is described. The purification of 125I-glucagon with polyacrylamide gel electrophoresis, the characterization of the tracer, its stability and the immunological properties are described. (author)

  11. The labeling of [Tyr3]-octreotide with 125I and its biodistribution and pharmacokinetic

    International Nuclear Information System (INIS)

    Objective: To investigate labeling method of [Tyr3]-octreotide with 125I and the biodistribution of 125I-[Tyr3]-octreotide in mice. Methods: [Tyr3]-octreotide was labeled with 125I using the method of Chloramine-T at room temperature. NH4HAc added to inhibit re-oxidation of 125I- [Tyr3]-octreotide. The radio-chemical purity was tested with XINHUA 1 chromatography paper. Its biodistribution in normal mice was analyzed. Results: The specific activity of the labeling product was 5.92TBq/mmol, The labeled yield was 76%, the radiochemical purity was 95%. At 1.0h after injection, radioactivity in blood decreased by 90%. Obvious accumulation of 125I in the intestinal-liver and kidney was observed. A great amount of radioactivity was detected within 24h. The pharmacokinetic characteristics of 125I-[Tyr3]-octreotide conformed to a two compartment open model, T1/2? was 5.28 min, T1/2? was 141.3 min. Conclusions: The method is simple and easy to perform. The radiochemical purity is high. Labeling of 125I-[Tyr3]-octreotide is stabile. Blood clearance of 125I-[Tyr3]-octreotide in normal mice is quiet fast. It is excreted through gastrointestinal-liver and kidney tract. (authors)

  12. American Brachytherapy Society (ABS) recommendations for transperineal permanent brachytherapy of prostate cancer

    International Nuclear Information System (INIS)

    Purpose/Objective: To develop and disseminate the American Brachytherapy Society (ABS) recommendations for the clinical quality assurance and guidelines of permanent transperineal prostate brachytherapy with 125I or 103Pd. Methods and Materials: The ABS formed a committee of experts in prostate brachytherapy to develop consensus guidelines through a critical analysis of published data supplemented by their clinical experience. The recommendations of the panels were reviewed and approved by the Board of Directors of the ABS. Results: Patients with high probability of organ-confined disease are appropriately treated with brachytherapy alone. Brachytherapy candidates with a significant risk of extraprostatic extension should be treated with supplemental external beam radiation therapy (EBRT). Patient selection guidelines were developed. Dosimetric planning of the implant should be carried out for all patients before seed insertion. A modified peripheral loading is preferred. The AAPM TG-43 recommendations requiring a change in prescription dose for 125I sources should be universally implemented. The recommended prescription doses for monotherapy are 145 Gy for 125I and 115-120 Gy for 103Pd. The corresponding boost doses (after 40-50 Gy EBRT) are 100-110 Gy and 80-90 Gy, respectively. Clinical evidence to guide selection of radionuclide (103Pd or 125I) is lacking. Post implant dosimetry and evaluation must be performed on all patients. It is suggested that the dose that covers 90% (D90) and 100% (D100) of the prostate volume and the percentage of the prostate volume receiving the prescribed dose (V100) be obtained from a dose-volume histogram (DVH) and reported. Conclusion: Guidelines for appropriate patient selection, dose reporting, and improved quality of permanent prostate brachytherapy are presented. These broad recommendations are intended to be technical and advisory in nature, but the ultimate responsibility for the medical decisions rests with the treating physician. This is a constantly evolving field, and the recommendations are subject to modifications as new data becomes available

  13. Internal contamination monitoring of personnel handling 125I in RIA laboratories

    International Nuclear Information System (INIS)

    A simple method for the monitoring of the content of 125I in the thyroid gland of workers employed in RIA laboratories who handle Na125I solutions during iodinations and other operations is described. A collimating scintillation detector with a thin NaI(Tl) crystal, 2 mm thickness, which was calibrated by means of a known activity of 125I contained in a suitable phantom was used. The thyroid gland dose was calculated on the surface measured below the curve of the time course of the 125I content in this organ. The detected dose in the thyroid gland of one worker reached one twelfth of the maximum annual permissible dose. The internal contamination with 125I of the workers in RIA laboratories must be monitored at regular intervals and evaluated in relation to the dose limits. (author)

  14. Method of separating (125I)-L-thyroxine from mixture obtained by radioiodination

    International Nuclear Information System (INIS)

    (125I)-L-thyroxine is separated by gel filtration on a column from the mixture of (125I)-L-thyroxine, (125I)-L-3,5,3'-triiodothyronine and (125I)-. The column is packed with a non-polar gel such as polydextran with particle size 25 to 100 ?m. The mixture 1,2-propanediol/distilled water/concentrated (26%) aqueous ammonia solution, or 1,2-propanediol/concentrated (26%) aqueous ammonia solution is used as eluent. The concentration of the eluate containing (125I)-L-thyroxine is adjusted with distilled water such as to establish a 50 vol.% concentration of 1,2-propanediol. (E.S.)

  15. Development of procedure using plasma welding process to produce {sup 125}I seeds; Desenvolvimento de procedimento utilizando processo de soldagem plasma para confeccao de sementes de {sup 125}I

    Energy Technology Data Exchange (ETDEWEB)

    Feher, Anselmo

    2006-07-01

    The prostate cancer, which is the second cause of death by cancer in men, overcome only by lung cancer, is a problem of public health in Brazil. Brachytherapy is among the possible available treatments for prostate cancer, in which small seeds containing {sup 125}I radioisotope are implanted in the prostate. The seed consists of a titanium sealed capsule with 0.8 mm external diameter and 4.5 mm length, containing a central silver wire with adsorbed {sup 125}I. The plasma arc welding is one of the viable techniques for the sealing process. The equipment used in this technique is less costly than in other processes. The main objective of this work was the development and the validation of the welding procedure using plasma welding process and the elaboration of a sealing routine according to Good Manufacturing Practices. The development of this work has presented the following phases: cut and cleaning of the titanium material, determination of the welding parameters, development of a device for holding the titanium tube during the welding process, validation of sealed sources according to ISO 2919 Sealed Radioactive Sources - General Requirements and Classification, leakage test according to ISO 9978 Sealed Radioactive Sources - Leakage Test Methods and metallographic assays. The developed procedure, to seal {sup 125}I seeds using plasma welding process, has shown to be efficient, satisfying all the established requirements of ISO 2919. The results obtained in this work have given the possibility to establish a routine production process according to the orientations presented in resolution RDC number 59 - Good Manufacturing Practices do Medical Products of the ANVISA - Brazilian Nacional Agency of Sanitary Surveillance. (author)

  16. Side effects of permanent I125 prostate seed implants in 667 patients treated in Leeds

    International Nuclear Information System (INIS)

    Purpose: To report the side effects and complications after I-125 seeds prostate implant after 8.5 years experience. Methods and materials: Six hundred and sixty seven (667) patients were treated between March 1995 and December 2001. The median follow up is 31 months with a maximum of 98.2 months. Morbidity data were collected from a review of patient case-notes. Patients also provided prospective data on urinary symptoms using the International Prostate Symptom Score (IPSS) scoring chart before treatment and at regular follow up. Patients were also sent a questionnaire detailing symptoms and side effects following their brachytherapy. This enabled them to record urinary, bowel and sexual function side effects independently. Logistic regression analysis was carried out to identify the risk of catheterisation in relation to the pre-implant prostate volume and potential implant factors such as the number of seeds and needles and implant dose. Result: The urinary symptom score rises in the first few months after implantation and returns to within one or two points of the pre-treatment score within one year. Nine patients reported incontinence prior to treatment and 15, 12 and 10 patients reported incontinence 6, 12 and 24 months after treatment, respectively. Catheterisation was reported in 97 (14.5%) patients. At six months 84.9% of patients reported no change in bowel function and 78.9% at 12 months. 6.4% of patients complained of some increased bowel frequency at 6 months and 5.7% at 12 months. 402 (77.2%) patients reported being fully potent before treatment and that this fell to 32.4% after treatment. Logistic regression showed that the most significant factors which correlate with the probability of catheterisation are the pre-treatment prostate volume and the number of seeds and needles implanted. Conclusion: The side effects and complications after prostate brachytherapy as reported here and elsewhere confirm that the treatment is not only convenient but also has a low risk of serious long term side effects

  17. Distal movement of upper permanent molars using midpalatal mini-implant

    Scientific Electronic Library Online (English)

    Ana de Lourdes Sá de, Lira; Sávio, Prado; Mônica Tirre, Araújo; Eduardo Franzotti, Sant' Anna; Antonio Carlos de Oliveira, Ruellas.

    2013-04-01

    Full Text Available OBJETIVO: verificar se o mini-implante no palato é eficaz como ancoragem direta para distalização dos molares superiores. MÉTODOS: foi utilizado um modelo em acrílico da arcada superior. Após a confecção da canaleta na região correspondente aos alvéolos dentários, os dentes em acrílico foram fixados [...] com cera #7, montado aparelho ortodôntico com a técnica Edgewise e inserido um mini-implante (SIN, São Paulo) no local correspondente à rafe palatina. Foram colocados arco 0,19" x 0,25" e barra transpalatina, soldados na barra dois ganchos para retenção de dois elásticos em cadeia de dois elos, a uma carga de 150g/f de cada lado (Unitek), que se estenderam dos ganchos até o mini-implante. O modelo da maxila foi mergulhado 40 vezes em banheira e fotografado após cada mergulho para observação da movimentação dentária. Os dados foram analisados pela análise da variânçia (ANOVA) e teste de Tukey. RESULTADOS: os molares deslocaram-se distalmente 3,1mm, em média, com inclinação distal entre 3 e 5mm. CONCLUÕES: a movimentação dos molares ocorreu pela inclinação distal, com leve rotação, mas sem efeito extrusivo. Abstract in english OBJECTIVE: To assess whether palatal mini-implants are effective as direct anchorage for distal movement of the upper molars. METHODS: It was used an acrylic model of the upper dental arch. After making a groove in the region corresponding to dental alveolus, acrylic teeth were fixed in groove with [...] #7 wax, with the roots being previously immersed in adhesive wax. The orthodontic appliance was placed according to the Edgewise technique and then a mini-implant (SIN, São Paulo, Brazil) was inserted at the site corresponding to the palatal raphe. A 0.019 x 0.025-in stainless steel archwire was made and attached to the upper arch with elastics. A transpalatal arch bar (0.019 x 0.025in) was mounted and two hooks were soldered to it in order to retain chain elastics (Unitek, Brazil) to be connected to the mini-implant under a force of 1.5 N on each side. The maxillary model was immersed in water 40 times and photographed after each immersion, for observation of dental movements. Analysis of variance (ANOVA) and Tukey's test were employed for analyzing the obtained data. RESULTS: Molars displaced distally 3.1 mm, in average, with distal inclination ranging from 3 to 5 mm. CONCLUSIONS: Molar movements occurred due to distal inclination, with a slight rotation and no extrusive effect.

  18. Permanent transvenous pacemaker implantation in a patient with Cor triatriatum dextrum

    OpenAIRE

    Kun XIANG; Moukarbel, George V; Grubb, Blair

    2015-01-01

    Cor triatriatum dextrum is an extremely rare congenital heart abnormality in which the right atrium is separated into two chambers by a persistent fibrous membrane. A transvenous approach to place a dual-chamber pacemaker in such patients is technically challenging. We report the first case of a transvenous permanent pacemaker placement in a patient with cor triatriatum dextrum. An 87-year-old woman was diagnosed with paroxysmal atrial fibrillation. She was accidentally found to have cor tria...

  19. Five-year outcome of intraoperative conformal permanent I-125 interstitial implantation for patients with clinically localized prostate cancer

    International Nuclear Information System (INIS)

    Purpose: To report the 5-year tumor control and toxicity outcomes for patients with localized prostate treated with I-125 permanent implantation using an intraoperative real-time conformal planning technique. Methods and Materials: Between January 1998 and June 2002, 367 patients with prostate cancer were treated with I-125 permanent interstitial implantation using a transrectal ultrasound-guided approach. Real-time intraoperative treatment planning which incorporated inverse planning optimization was used. The median follow-up time was 63 months. Results: The median V100 and D90 were 96% and 173 Gy, respectively. In 96% of cases a D90 of >140 Gy was achieved. The median urethral and rectal doses were 100% and 33% of the prescription doses, respectively. The 5-year PSA relapse-free survival outcomes for favorable and intermediate risk patients according to the ASTRO definition were 96% and 89%, respectively. In these patients no dosimetric parameter was identified which influenced the biochemical outcome. Of 38% who developed acute Grade 2 urinary symptoms, 63% had resolution of their symptoms within a median time of 6 months. The incidence of late rectal and urinary Grade 3 or higher toxicities were 1% and 4%, respectively. Seven percent (n = 27) developed late rectal bleeding (Grade 2) and 19% experienced late Grade 2 urinary symptoms. Conclusion: Real-time intraoperative planning consistently achieved optimal coverage of the prostate with the prescription dose with concomitant low doses delivered to the urethra and rectum. Biochemical control outcomes were excellent at 5 years and late toxicity was unusual. These data demonstrate that real-time planning methods can consistently and reliably deliver the intended dose distribution to achieve an optimal therapeutic ratio between the target and normal tissue structures

  20. Tolerance and Acceptance Results of a Palladium-103 Permanent Breast Seed Implant Phase I/II Study

    International Nuclear Information System (INIS)

    Purpose: To test, in a prospective Phase I/II trial, a partial breast irradiation technique using a 103Pd permanent breast seed implant (PBSI) realized in a single 1-h procedure under sedation and local freezing. Methods and Materials: Eligible patients had infiltrating ductal carcinoma ?3 cm in diameter, surgical margin ?2 mm, no extensive intraductal component, no lymphovascular invasion, and negative lymph nodes. Patients received a permanent seed implant, and a minimal peripheral dose of 90 Gy was prescribed to the clinical target volume, with a margin of 1.5 cm. Results: From May 2004 to April 2007, 67 patients received the PBSI treatment. The procedure was well tolerated, with 17% of patients having significant pain after the procedure. Only 1 patient (1.5%) had an acute skin reaction (Grade 3 according to the National Cancer Institute Common Toxicity Criteria). The rates of acute moist desquamation, erythema, and indurations were 10.4%, 42%, and 27%, respectively. At 1 year the rate of Grade 1 telangiectasia was 14%. The rate of skin reaction decreased from 65% to 28% when skin received less than the 85% isodose. According to a Radiation Therapy Oncology Group questionnaire, 80-90% of patients were very satisfied with their treatment, and the remainder were satisfied. One patient (1.5%) developed an abscess, which resolved after the use of antibiotics. There was no recurrence after a median follow-up of 32 months (range, 11-49 months). Conclusions: The feasibility, safety, and tolerability of PBSI compares favorably with that of external beam and other partial breast irradiation techniques.

  1. The distribution of 125I-metrizamide and 125I-diatrizoate between blood, brain and cerebrospinal fluid in the rabbit

    International Nuclear Information System (INIS)

    The entry of 125I-metrizamide and of 125I-diatrizoate from blood into brain has been studied in rabbits. The blood-brain barrier is very tight to both molecules, all cerebral regions having spaces between 0.5 and 2% after maintenance of constant blood levels for 4 h. In extraneural tissues both compounds appear to distribute in extracellular fluid except for accumulation of metrizamide by the liver and perhaps the small intestine. Profiles of radioactivity through cerebral gray matter have been obtained following ventriculocisternal perfusion of artificial cerebrospinal fluid containing 125I-metrizamide. The nature of these profiles and their behaviour with time suggest that metrizamide passes through gray matter by simple diffusion, that it is largely distributed in the extracellular fluid and that back movement across the blood-brain barrier is small. (orig.)

  2. In line assessment of pulmonary removal of 125I-histidyl prostaglandin E2 (125I-PGE2) by perfused rabbit lungs in situ

    International Nuclear Information System (INIS)

    The authors recently reported application of an in-line system to quantify single-pass binding of an iodinated inhibitor of angiotensin-converting enzyme. To provide additional information regarding pulmonary metabolic function, they compared the disposition of 125I-PGE2 with 3H-PGE2 in Krebs-albumin perfused rabbit lungs in situ. Apparent kinetics (V/sub max/ = maximal velocity; Km = [PGE2] at V/sub max//2) were measured from indicator dilution curves evaluated from discontinuous samples of pulmonary venous effluent after bolus injection of 3H-PGE2 with and without 50 nmol PGE2 (n=6) or 125I-PGE2 with and without histidyl-PGE2 (10-57 nmol; n=2). Pulmonary removal of 3H-PGE2 was 95 +/- 1%, and apparent kinetics were: Km = 0.9 +/- 0.1 ?M, V/sub max/ = 3.5 +/- 0.4 nmol/s. Pulmonary removal of 125I-PGE2 was 39% and Km and V/sub max/ were 3.5 ?M and 1.7 nmol/s, respectively. With two perfused lungs, injected with 125I-PGE2 and /sup 99m/Tc-sulfur colloid, effluent was diverted past a nuclear detection system interfaced with a computer. Pulmonary removal of 125I-PGE2 was reversibly depressed when perfusate temperature was lowered from 370 to 70C. These data suggest that 125I-PGE2 is removed by a saturable, temperature sensitive process with apparent kinetics similar to that of authentic PGE2

  3. ( sup 125 I)Iodoazidococaine, a photoaffinity label for the haloperidol-sensitive sigma receptor

    Energy Technology Data Exchange (ETDEWEB)

    Kahoun, J.R.; Ruoho, A.E. (Univ. of Wisconsin, Madison (United States))

    1992-02-15

    A carrier-free radioiodinated cocaine photoaffinity label, (-)-3-({sup 125}I)iodo-4-azidococaine (({sup 125}I)IACoc), has been synthesized and used as a probe for cocaine-binding proteins. Photoaffinity labeling with 0.5 nM ({sup 125}I)IACoc resulted in selective derivatization of a 26-kDa polypeptide with the pharmacology of a sigma receptor in membranes derived from whole rat brain, rat liver, and human placenta. ({sup 125}I)IACoc labeling of the 26-kDa polypeptide was also inhibited by 10 {mu}M imipramine, amitriptyline, fluoxetine, benztropine, and tetrabenazine. The size of the ({sup 125}I)I-ACoc-labeled proteins is consistent with the size of proteins photolabeled in guinea pig brain and liver membranes by using the sigma photolabel azido-({sup 3}H)DTG. Kinetic analysis of ({sup 125}I)IACoc binding to rat liver microsomes revealed two sites with K{sub d} values of 19 and 126 pM, respectively. The presence or absence of proteolytic inhibitors during membrane preparation did not alter the size of the photolabeled sigma receptor, indicating that the 26-kDa polypeptide was not derived from a larger protein. In summary, ({sup 125}I)IACoc is a potent and highly specific photoaffinity label for the haloperidol-sensitive sigma receptor and will be useful for its biochemical and molecular characterization.

  4. (125I)Iodoazidococaine, a photoaffinity label for the haloperidol-sensitive sigma receptor

    International Nuclear Information System (INIS)

    A carrier-free radioiodinated cocaine photoaffinity label, (-)-3-(125I)iodo-4-azidococaine [(125I)IACoc], has been synthesized and used as a probe for cocaine-binding proteins. Photoaffinity labeling with 0.5 nM (125I)IACoc resulted in selective derivatization of a 26-kDa polypeptide with the pharmacology of a sigma receptor in membranes derived from whole rat brain, rat liver, and human placenta. (125I)IACoc labeling of the 26-kDa polypeptide was also inhibited by 10 ?M imipramine, amitriptyline, fluoxetine, benztropine, and tetrabenazine. The size of the (125I)I-ACoc-labeled proteins is consistent with the size of proteins photolabeled in guinea pig brain and liver membranes by using the sigma photolabel azido-[3H]DTG. Kinetic analysis of (125I)IACoc binding to rat liver microsomes revealed two sites with Kd values of 19 and 126 pM, respectively. The presence or absence of proteolytic inhibitors during membrane preparation did not alter the size of the photolabeled sigma receptor, indicating that the 26-kDa polypeptide was not derived from a larger protein. In summary, (125I)IACoc is a potent and highly specific photoaffinity label for the haloperidol-sensitive sigma receptor and will be useful for its biochemical and molecular characterization

  5. Exploration of dopamine transporter and D2 receptors in morphine dependent rats through 125I-?-CTT, 125I-IBZM cerebral autoradiography and the biodistribution study

    International Nuclear Information System (INIS)

    Objective: To explore the variation of cerebral dopamine (DA) transmitting system in morphine dependent (MD) rats using dopamine transporter (DAT) and D2 receptors imaging agent. Methods: MD model rats were established by using a two-compartment (C1 and C2-morphine conditioned compartment) apparatus for assessing morphine conditioned place preferences in rats. 125I-2?-carbomethoxy-3?-(4-iodophenyl) tropane (125I-?-CIT) and 125I-3-iodo-2-hydroxy-6-methoxy-N[(1-ethyl-2-pyrrolidinyl) methyl] benzamide (125I-IBZM) cerebral DAT and D2 receptor autoradiography and biodistribution study were used to evaluate the variation of DAT and D2 receptors in morphine dependent rats. Results: The mean time of MD rats entering from C1 to C2 was (0.84 +- 0.50) min after 6 days' conditioned place preference training, shorter than that of the control group [(2.40 +- 1.10) min, P 125I-?-CIT uptake ratio of striatum (ST)/cerebellum (CB) and nucleus acumens (NAC)/CB in MD group were 4.76 +- 0.92 and 2.72 +- 0.96, significantly lower than that of control group (5.92 +- 0.67 and 4.16 +- 0.56, P 125I-IBZM uptake ratio in MD group were 4.11 +- 0.56 and 2.64 +- 0.25, lower than that in control group (5.43 +- 0.74 and 3.49 +- 0.65, P 125I-?-CIT, 125I-IBZM biodistribution study also showed that the DAT and D2 binding sites were reduced in ST of MD group by (21.68 +- 11.11)% and (18.69 +- 9.97)% comparing to the controls, respectively. Conclusions: The DAT and D2 receptors in both ST and NAC were all involved and reduced to some extent in morphine dependent model rats, the DAT and D2 receptor imaging agent could reflect the variation of DAT and D2receptors, this would afford the theoretical basis for D2 receptors and DAT imaging in study on preventing drug addiction and on its abstinence

  6. Permanent prostate implant using high activity seeds and inverse planning with fast simulated annealing algorithm: A 12-year Canadian experience

    International Nuclear Information System (INIS)

    Purpose: To report outcomes and toxicity of the first Canadian permanent prostate implant program. Methods and Materials: 396 consecutive patients (Gleason ≤6, initial prostate specific antigen (PSA) ≤10 and stage T1-T2a disease) were implanted between June 1994 and December 2001. The median follow-up is of 60 months (maximum, 136 months). All patients were planned with fast-simulated annealing inverse planning algorithm with high activity seeds ([gt] 0.76 U). Acute and late toxicity is reported for the first 213 patients using a modified RTOG toxicity scale. The Kaplan-Meier biochemical failure-free survival (bFFS) is reported according to the ASTRO and Houston definitions. Results: The bFFS at 60 months was of 88.5% (90.5%) according to the ASTRO (Houston) definition and, of 91.4% (94.6%) in the low risk group (initial PSA ≤10 and Gleason ≤6 and Stage ≤T2a). Risk factors statistically associated with bFFS were: initial PSA >10, a Gleason score of 7-8, and stage T2b-T3. The mean D90 was of 151 ± 36.1 Gy. The mean V100 was of 85.4 ± 8.5% with a mean V150 of 60.1 ± 12.3%. Overall, the implants were well tolerated. In the first 6 months, 31.5% of the patients were free of genitourinary symptoms (GUs), 12.7% had Grade 3 GUs; 91.6% were free of gastrointestinal symptoms (GIs). After 6 months, 54.0% were GUs free, 1.4% had Grade 3 GUs; 95.8% were GIs free. Conclusion: The inverse planning with fast simulated annealing and high activity seeds gives a 5-year bFFS, which is comparable with the best published series with a low toxicity profile

  7. Incidence of seed migration to the chest, abdomen, and pelvis after transperineal interstitial prostate brachytherapy with loose 125I seeds

    Directory of Open Access Journals (Sweden)

    Shiraishi Yutaka

    2011-10-01

    Full Text Available Abstract Background The aim was to determine the incidence of seed migration not only to the chest, but also to the abdomen and pelvis after transperineal interstitial prostate brachytherapy with loose 125I seeds. Methods We reviewed the records of 267 patients who underwent prostate brachytherapy with loose 125I seeds. After seed implantation, orthogonal chest radiographs, an abdominal radiograph, and a pelvic radiograph were undertaken routinely to document the occurrence and sites of seed migration. The incidence of seed migration to the chest, abdomen, and pelvis was calculated. All patients who had seed migration to the abdomen and pelvis subsequently underwent a computed tomography scan to identify the exact location of the migrated seeds. Postimplant dosimetric analysis was undertaken, and dosimetric results were compared between patients with and without seed migration. Results A total of 19,236 seeds were implanted in 267 patients. Overall, 91 of 19,236 (0.47% seeds migrated in 66 of 267 (24.7% patients. Sixty-nine (0.36% seeds migrated to the chest in 54 (20.2% patients. Seven (0.036% seeds migrated to the abdomen in six (2.2% patients. Fifteen (0.078% seeds migrated to the pelvis in 15 (5.6% patients. Seed migration occurred predominantly within two weeks after seed implantation. None of the 66 patients had symptoms related to the migrated seeds. Postimplant prostate D90 was not significantly different between patients with and without seed migration. Conclusion We showed the incidence of seed migration to the chest, abdomen and pelvis. Seed migration did not have a significant effect on postimplant prostate D90.

  8. Combination of bilateral pelvic lymphadenectomy, permanent iodine-125 implantation, and percutaneous irradiation of the locally confined prostatic cancer. Pt. 1

    International Nuclear Information System (INIS)

    Since the beginning of 1981, 32 patients at an age of 52 to 72 years who suffered from a locally confined adenocarcinoma of the prostate were treated by permanent implantation of I-125 seeds. 25 patients were evaluated after a median observation period of 30 months. The first group consisting of 19 patients was submitted to a combined percutaneous and interstitial treatment, the other 6 patients were initially treated only by interstitial therapy because of severe complications observed in the meantime. After bilateral pelvic staging lymphadenectomy, permanent I-125 seeds were implanted into the patients of stage T1, T2, early T3 and pN0-1, in case of microscopic lymph node manifestation without capsular perforation also into patients of stage pN2 and pN4. 8 weeks later the patients received a moving beam irradiation with 10 MV photons at the linear accelerator. The centre of the prostate was faded out by a specially constructed H absorber in such a way that the prescribed target dose of 36 Gy in 4 weeks to the 90%-isodose was only applied to a spherical surface around the implant. 1 patient died perioperatively from an embolism due to phlebothrombosis of the thigh. 22 out of the other 24 patients are in complete remission, 1 patient had a local recurrence in the right seminal vesicle which appeared 28 months after primary therapy, and 1 patient developed skeletal metastases. The objective side effects and late complications of our combined treatment are considerable with respect to their incidence as well as their severity: a slight or medium radioproctitis was found after a latent period of 1 to 2 years in 28% (5/18) of cases, after a latent time of about 1 1/2 to 2 years another 28% (5/18) developed subsequently to a proctitis an urethral stricture and an ulcer situated on the anterior rectum wall facing the prostate, and 4 patients presented finally a prostato-rectal fistula. (orig.)

  9. 125I-labeled crosslinking reagent that is hydrophilic, photoactivatable, and cleavable through an azo linkage.

    OpenAIRE

    Denny, J B; Blobel, G.

    1984-01-01

    A radioactive crosslinking reagent, N-[4-(p-azido-m-[125I]iodophenylazo)benzoyl]-3-aminopropyl-N' -oxysulfosuccinimide ester, has been synthesized. The reagent is photoactivatable, water-soluble, cleavable through an azo linkage, and labeled with 125I at the carrier-free specific activity of 2000 Ci/mmol. Any protein derivatized with the reagent is thus converted into an 125I-labeled photoaffinity probe. Crosslinks are formed following photolysis with 366-nm light, and cleavage by sodium dith...

  10. Accumulation of 125I-labelled thiouracil and propylthiouracil in murine melanotic melanomas.

    OpenAIRE

    Larsson, B.; Olander, K.; Dencker, L.; Holmqvist, L.

    1982-01-01

    We have shown that thioamides are incorporated as false precursors into melanin during its synthesis. To be clinically useful in the diagnosis or therapy of melanotic melanomas, they would have to be tagged with an appropriate isotope or possibly a cytotoxic moiety. 125I-Thiouracil (125I-TU) is here shown to be accumulated in the melanin of melanotic melanomas transplanted into mice in a similar way as is 14C-thiouracil (14C-TU). 125I-TU gives tumour/liver and tumour/muscle ratios up to 22 an...

  11. Labelling of ochratoxins with sup 3 H or sup 125 I

    Energy Technology Data Exchange (ETDEWEB)

    Schmiedova, D.; Veres, K.; Cerny, B. (Ceskoslovenska Akademie Ved, Prague (Czechoslovakia). Ustav Nuklearni Biologie a Radiochemie); Ruprich, J. (Institut Hygieny a Epidemiologie, Prague (Czechoslovakia)); Nemecek, J. (Slovak Academy of Sciences, Prague (Czechoslovakia). Inst. of Microbiology)

    1989-01-01

    Catalytic hydrogenation of ochratoxin A by carrier-free tritium was used to prepare {sup 3}H-ochratoxin B with a high specific activity. Iodination of ochratoxin B by carrier-free Na {sup 125}I using the chloramine method yielded {sup 125}I-ochratoxin with a high specific activity. Another {sup 125}I-derivative of ochratoxin A was prepared by iodination of an ochratoxin A - L-tyrosine-methylester conjugate. All three radioactive preparations were found to be useful for radioimmunoassay. (author).

  12. Effect of fentanyl on 125I-?-CIT uptake in mice brain

    International Nuclear Information System (INIS)

    Objective: To investigate the effect of fentanyl on 125I-2?-carbomethoxy-3?-(4-iodophenyl) tropane (125I-?-CIT) uptake in mice brain. Methods: 1) KM mice groups of five were given different doses of fentanyl, and 10 min or 1 h later were given a dose of 125I-?-CIT. 2)Two groups of animals were killed at 2 h after injection of 125I-?-CIT. 3)One group of animals were killed at 1 h after injection of 125I-?-CIT. Results: 1)In the striatum, frontal cortex, hippocampus, brain stem, cerebellum and whole brain, a dose-dependent increase in uptake (%ID/g or %ID) of 125I-?-CIT was detected at the fentanyl doses ranging from 125 to 300 ?g/kg, and the uptakes of hippocampus and cerebellum were higher than that of the controls. There was a great difference in the value of %ID/g or %ID between the group treated with 250 ?g/kg fentanyl and the control group; while at the doses from 12.5 to 100 ?g/kg, a dose-dependent decrease in uptake in the same regions was observed and all the uptake levels were lower (hippocampus: except 62.5 and 12.5 ?g/kg groups; brain stem: except 62.5 ?g/kg group) than that of the controls. 2)The uptakes of 125I-?-CIT in the striatum, frontal cortex, hippocampus, brain stem, cerebellum and whole brain in the groups injected with 125I-?-CIT 10 min after fentanyl treatment were higher than that in the groups injected with 125I-?-CIT 1 h after fentanyl treatment. 3)The binding of 125I-?-CIT in the striatum, frontal cortex, hippocampus, brain stem, cerebellum and whole brain in the groups killed at 1 h after injection of 125I-?-CIT was higher than that in the control group, but without significant difference. Conclusion: Fentanyl may have different effects on 125I-?-CIT at various time points and doses

  13. In vivo study about specific captation of 125 I-insulin by rat brain structures

    International Nuclear Information System (INIS)

    The specific captation of 125 I-insulin was evaluated by brain structures, as olfactory bulbous, hypothalamus and cerebellum in rats, from in vivo experiences that including two different aspects: captation measure of 125 I-insulin after the intravenous injection of the labelled hormone, in fed rats and in rats with 48 h of fast or convulsion, procedure by the pentylene tetrazole; captation measure of 125 I-insulin after intra-cerebral-ventricular injection of the labelled hormone in fed rats. (C.G.C.)

  14. m-[125I]iodoaniline: a useful reagent for radiolabeling biotin

    International Nuclear Information System (INIS)

    Biotinyl-m-[125I]iodoanilide (BIA) was synthesized by coupling biotin to m-[125I]iodoaniline via a mixed anhydride reaction. m-[125I]Iodoaniline was produced from the tin precursor, which was prepared using a palladium catalyzed reaction of hexabutylditin with m-bromoaniline. The radioiodinated BIA derivative is characterized by a stable amide and/or intact ureido group on the biotin molecule, it may thus be a useful carrier for targeting radionuclides to avidin-conjugated antibodies previously localized on tumors. (author)

  15. Characterization of propranolol-resistant (-)-[125I]-cyanopindolol binding sites in rat soleus muscle.

    OpenAIRE

    Roberts, S. J.; Molenaar, P.; Summers, R. J.

    1993-01-01

    1. The characteristics of a propranolol-resistant (-)-[125I]-cyanopindolol (CYP) binding site in rat soleus muscle were determined. 2. Saturation studies performed on homogenates of rat soleus muscle showed two phases of (-)-[125I]-CYP binding, a high affinity site (KD1 30.5 +/- 16.3 pM, Bmax 9.4 +/- 1.38 fmol mg-1 protein) and a lower affinity site (KD2 522.5 +/- 29.1 pM, Bmax 62.19 +/- 11.76 fmol mg-1 protein, n = 4). 3. In rat soleus muscle homogenates labelled with (-)-[125I]-CYP (500 pM)...

  16. Use of an 125I-labelled DNA ligand to probe DNA structure

    International Nuclear Information System (INIS)

    A simple way to endow a DNA-binding ligand with the ability to cleave DNA-labelling with 125I is described. The radiochemical damage associated with 125I decay induces a double-stranded DNA break. Using this technique it is shown that a sequence of four consecutive A.T base pairs is a necessary, but not sufficient, condition for strong binding to DNA of the bis-benzamide Hoechst 33258 and it is suggested that 125I-Hoechst 33258 may be a useful new probe of DNA structure. (U.K.)

  17. Impact of different dose distribution of 125I seeds interstitial brachytherapy on the effects in human gastric carcinoma bearing nude mice

    International Nuclear Information System (INIS)

    Objective: 125I seeds interstitial brachytherapy has been clinically used for years. How- ever, how the dose distribution affects the therapeutic response remains to be elucidated. The present study was undertaken to investigate the impact of different dose distribution on the effects of 125I seeds interstitial brachytherapy. Methods: Thirty-two human gastric carcinoma bearing nude mice were randomly divided in- to three treated groups and one control group with eight mice in each group. 125I seeds were implanted in the treated groups with the same total activity (33.30 MBq). Based on the dose distribution and activity of single seed, the treated groups were classified to high activity group (33.30 MBq x 1), moderate activity group (16.65 MBq x 2) and low activity group (11.10 MBq x 3). The control group was implanted radioactivity-free seeds. The evaluation parameters were obtained after 30 d, which included survival rate, body weight, volume inhibitory rate, histological tumor regression and regional skin reaction. Analysis of variance and Kruskal-Wallis H test were used for data statistical analysis. Results: All mice survived during the observation period. There was no significant difference of the body weight among the groups after 125I seeds implantation (F=2.23, P>0.05). The volume inhibitory rates in high, moderate and low activity groups were 92.47%, 97.15% and 89.01%, respectively. After treatment the average tumor volume was (138.85 ± 16.45) mm3 in high activity group, (52.52 ± 30.54) mm3 in moderate activity group, (202.72 ± 126.97) mm3 in low activity group and (1843.99 ± 447.63) mm3 in control group. In all treated groups, the average tumor volume was significantly smaller than that in control group (t=3.092, 3.376, 3.269, all P125I seed and the dose distribution may exert critical impact on the therapeutic effects and radiation injury in 125I seeds interstitial brachytherapy. (authors)

  18. Dose to fingertips of staff preparing stranded iodine-125 seeds for permanent prostate implants

    International Nuclear Information System (INIS)

    The aim of this study is to measure radiation dose to the fingertips of occupationally exposed workers handling stranded iodine-125 seeds during prostate implants. The doses were measured by thermoluminescence dosimetry at the nail of the index finger of both hands in three hospitals in the Netherlands. In all hospitals, measurements were carried out during the preparation of stranded IBt seeds, type IntersourceR 1251L. The fingertip doses per procedure (mean ± SD) to the fingertip for workers from the three hospitals were estimated to be 0.29 ± 0.15 mSv (n=6), <0.03 ± <0.02 mSv (n=8) and 0.31 ± 0.16 mSv (n=16), respectively. The lower doses found for the hospital 2 workers are presumably related to the heavier shielding and longer utensils used in that hospital. Even in the case of hundreds of implant procedures per year, dose to the fingertips for occupationally exposed workers preparing stranded seeds is expected to be well below the annual limit for extremities of 500 mSv. (authors)

  19. The brachytherapy by implants of iodine 125 in the localised prostate cancer; La curietherapie par implants permanents d'iode 125 dans le cancer de la prostate localise

    Energy Technology Data Exchange (ETDEWEB)

    Cecconi, A.; Guido, A.; Vicenzi, L.; Galuppi, A.; Barbieri, E. [U.O. Radioterapia, Policlinico S.-Orsola-Malpighi, Bologne (Italy)

    2007-11-15

    The brachytherapy by permanent iodine 125 implants is in the localised prostate cancer a clinical treatment well tolerated and characterized by a limited toxicity: the urinary flow before implantation is an important factor of evolution prediction of the acute urinary toxicity, especially with regard to acute urinary retention. The important number of gains implanted near urethra is responsible of the acute urinary toxicity. All patients were in a state of complete remission with a decrease in the concentration of serum P.S.A. to eight months. (N.C.)

  20. Isotope and Patient Age Predict for PSA Spikes After Permanent Prostate Brachytherapy

    International Nuclear Information System (INIS)

    Purpose: To evaluate prostate-specific antigen (PSA) spikes after permanent prostate brachytherapy in low-risk patients. Methods and Materials: The study population consisted of 164 prostate cancer patients who were part of a prospective randomized trial comparing 103Pd and 125I for low-risk disease. Of the 164 patients, 61 (37.2%) received short-course androgen deprivation therapy. The median follow-up was 5.4 years. On average, 11.1 post-treatment PSA measurements were obtained per patient. Biochemical disease-free survival was defined as a PSA level of ?0.40 ng/mL after nadir. A PSA spike was defined as an increase of ?0.2 ng/mL, followed by a durable decline to prespike levels. Multiple parameters were evaluated as predictors for a PSA spike. Results: Of the 164 patients, 44 (26.9%) developed a PSA spike. Of the 46 hormone-naive 125I patients and 57 hormone-naive 103Pd patients, 21 (45.7%) and 8 (14.0%) developed a PSA spike. In the hormone-naive patients, the mean time between implantation and the spike was 22.6 months and 18.7 months for 125I and 103Pd, respectively. In patients receiving neoadjuvant androgen deprivation therapy, the incidence of spikes was comparable between isotopes (125I 28.1% and 103Pd 20.7%). The incidence of spikes was substantially different in patients 125I and/or <65 years of age. Differences in isotope-related spikes are most pronounced in hormone-naive patients

  1. Distribution and levels of [125I]IGF-I, [125I]IGF-II and [125I]insulin receptor binding sites in the hippocampus of aged memory-unimpaired and -impaired rats

    International Nuclear Information System (INIS)

    The insulin-like growth factors (IGF-I and IGF-II) and insulin are localized within distinct brain regions and their respective functions are mediated by specific membrane receptors. High densities of binding sites for these growth factors are discretely and differentially distributed throughout the brain, with prominent levels localized to the hippocampal formation. IGFs and insulin, in addition to their growth promoting actions, are considered to play important roles in the development and maintenance of normal cell functions throughout life. We compared the anatomical distribution and levels of IGF and insulin receptors in young (five month) and aged (25 month) memory-impaired and memory-unimpaired male Long-Evans rats as determined in the Morris water maze task in order to determine if alterations in IGF and insulin activity may be related to the emergence of cognitive deficits in the aged memory-impaired rat. In the hippocampus, [125I]IGF-I receptors are concentrated primarily in the dentate gyrus (DG) and the CA3 sub-field while high amounts of [125I]IGF-II binding sites are localized to the pyramidal cell layer, and the granular cell layer of the DG. [125I]insulin binding sites are mostly found in the molecular layer of the DG and the CA1 sub-field. No significant differences were found in [125I]IGF-I, [125I]IGF-II or [125I]insulin binding levels in any regions or laminae of the hippocampus of young vs aged rats, and deficits in cognitive performance did not relate to altered levels of these receptors in aged memory-impaired vs aged memory-unimpaired rats. Other regions, including various cortical areas, were also examined and failed to reveal any significant differences between the three groups studied.It thus appears that IGF-I, IGF-II and insulin receptor sites are not markedly altered during the normal ageing process in the Long-Evans rat, in spite of significant learning deficits in a sub-group (memory-impaired) of aged animals. Hence, recently reported changes in IGF-I receptor messenger RNA levels in aged memory-impaired rats [42] are apparently not reflected at the level of the translated protein. (Copyright (c) 1997 Elsevier Science B.V., Amsterdam. All rights reserved.)

  2. External detection of ?-adrenoreceptors with 125I-hydroxybenzylpindolol in isolated perfused hearts

    International Nuclear Information System (INIS)

    To assess the feasibility of characterizing ?-adrenoreceptors externally with ligands labeled with ?-emitting radionuclides, we infused 125I-hydroxybenzylpindolol (125I-HYP) a potent, high affinity, ?-adrenoreceptor ligand into isolated perfused hearts and monitored uptake and release of the label externally with a gamma probe. Perfusion with specific ?-adrenergic displacing significantly increased the turnover rate constant of 125I-HYP in comparison to that obtained with non-specific displacing agents. After modifying ?-adrenoreceptor density by pretreatment of animals with thyroid hormone, an increase in 125I-HYP uptake was observed. Thus, ?-adrenoreceptor occupancy and increases in ?-adrenoreceptor density can be detected externally with an approach which may offer promise for their characterization in vivo with radiolabeled adrenergic ligands. (author)

  3. Radiosynthesis and in vivo evaluation of the pseudopeptide ?-opioid antagonist [125I]-ITIPP(?)

    International Nuclear Information System (INIS)

    The radioiodinated tetrapeptide ?-opioid antagonist [125I]ITIPP(?) [H-Tyr(3'I)-Tic?[CH2NH]Phe-Phe-OH] (Ki(?) 2.08 nM; Ki(?)/Ki(?) = 1280) has been synthesized and evaluated as a potential lung tumour imaging agent. [125I]ITIPP(?) was obtained, via electrophilic iodination, in 46% yield (>44,000 MBq/?mol) from the parent TIPP(?). The biodistribution of [125I]ITIPP(?) in nu/nu mice bearing SCLC-SW210.5 xenographs revealed good uptake and prolonged retention of radioactivity in organs known to possess ?-opioid receptors. Metabolite analysis showed that [125I]ITIPP(?) was largely unmetabolized at 25 min PI and blocking studies showed significant reduction of uptake of the tracer in the brain, liver, intestine and tumor indicating that the iodinated tetrapeptide binds to ? opioid receptors in vivo

  4. Accelerated Increase in the Decay of Radioactive 125I by X Ray Irradiation

    OpenAIRE

    Soloway, Sidney

    2001-01-01

    Expanded concepts of photonuclear reaction in Mossbauer type behavior were applied to radioactive nuclei. An enhanced reduction in radioactivity of 125I was achieved by X-Ray irradiation using the Brookhaven synchrotron.

  5. Radioiodination of ibuprofen with 125I and its biological behavior in mice

    International Nuclear Information System (INIS)

    A procedure for radioiodination of Ibuprofen with iodine-125 is carried out via an electrophilic substitution reaction. The reaction parameters were studied Ibuprofen concentration, pH of the reaction mixture, reaction time temperature, and different oxidizing agents to optimize the conditions for the labeling of Ibuprofen to abstain a high radiochemical yield of 125I-Ibuprofen (125I-Ib up). Using 3.7 MBq of of Na 125I, 100?g of ibuprofen as substrate and 100?g of iodogen as oxidizing agent in ethanol at 60 OC for 10 min, a maximum radiochemical yield of 125I-Ib up (78%) was obtained. The labeled compound was separated and purified from inactive Ibuprofen by means of high-pressure liquid chromatography (HPLC). The biological distribution in normal and inflamed mice indicates the suitability of radioiodinated Ibuprofen for imaging of inflammation only induced with turpentine oil. (Author)

  6. Proteolytic activity of beef liver determined by natural 125I-labelled substrates

    International Nuclear Information System (INIS)

    The method of determining the enzymatic activity of acid proteinases is described. The method is based on the use of 125I-labelled natural protein substrates. 125I-labelled albumin, 125I-globulin and 125I-insulin were tested for the determination of activities. All the substrates were hydrolyzed with the enzymes of the supernatant fraction (106,000 g) of beef liver homogenate in the acid pH zone. Optimum enzymatic reaction conditions were tested, the dependence of the reaction on the enzyme concentration, time and temperature was determined, pH optimum was ascertained for the individual substrates, and pH stability was determined. The results show that the method is suitable for determining the enzymatic activity of proteinases of cathepsin character. (author)

  7. (E)-[125I]-5-AOIBV: a SPECT radioligand for the vesicular acetylcholine transporter

    International Nuclear Information System (INIS)

    The premise that, over the course of Alzheimer's disease (AD), changes in the levels of the vesicular acetylcholine transporter (VAChT) occur in parallel with changes to other cholinergic marker proteins provides the basis for the applicability of benzovesamicol derivatives as radioligands for AD studies by single photon emission computed tomography or positron emission tomography. We report the synthesis of enantiopure benzovesamicol derivatives: (R,R) or (S,S)-(E)-2-hydroxy-5-(3-iodoprop-2-en-1-oxy)-3- (4-phenylpiperidino)tetralin [(R,R)-AOIBV: Kd=0.45 nM or (S,S)-5-AOIBV: Kd=4.3 nM] and their corresponding tributyltin precursors for radioiodination. (R,R or S,S)-5-AOIBV was labeled with iodine-125 from their corresponding n-tributyltin precursors. Both compounds were obtained with radiochemical and optical purity greater than 97% and in radiochemical yields ranging 34-36%. To determine if these compounds could provide an advantage when compared to [125I]-iodo benzovesamicol (IBVM), IBVM was also labeled and used as the reference compound in all ex vivo experiments. Ex vivo biodistribution experiments in rats revealed that [125I]-(R,R)-5-AOIBV displayed the most suitable pharmacological profile as the radioactivity distribution corresponded well with the known VAChT brain density. Moreover, pre-injection of vesamicol prevented the uptake of [125I]-(R,R)-5-AOIBV in striatum, cortex and hippocampus, demonstrating selectivity for the VAChT. However, even if time activity curves of [125I]-(R,R)-5-AOIBV confirmed that this compound could be used to visualize the VAChT in vivo, at each point of the kinetic study, [125I]-(R,R)-5-AOIBV showed a lower specific binding compared to [125I]-IBVM. These results made [125I]-( R,R)-5-AOIBV inferior to [125I]-IBVM for the VAChT exploration in vivo

  8. Relative biological effectiveness of 125I seeds for low-dose-rate irradiation of PANC-1

    International Nuclear Information System (INIS)

    Objective: To investigate the relative biological effectiveness(RBE) of National Model 6711 125I seeds and the response patterns of PANC-1 exposed to 125I seeds irradiation. Methods: PANC-1 cells in exponential growth were irradiated at initial dose rate of 2.59 cGy/h in vitro and exposed to 1, 2, 4, 6, 8 and 10 Gy. Meanwhile, the other part of cells were exposed to the same doses by 60Co at dose rate of 2.21 Gy/min. After irradiation, the cells were stained by trypan blue to measure the cellular mortality rate and to compare the changes along with plating times of 12, 24, 48 and 72 h after 4 Gy. The colonies were counted to obtain the plating efficiencies by colony-forming assay and the cell surviving faction was calculated to plot cell survival curves, and RBE of 125I seeds relative to 60Co was determined. Results: The cell death rate for continuous low- dose-rate (LDR) irradiation by 125I seeds was greater than 60Co at the same doses above or equal to 4 Gy. After 4 Gy irradiation, the cellular mortality rates were increased with times. The difference was significant between 125I seeds and 60Co. The survival fractions of 125I were lower than those of 60Co, and the RBE of 125I relative to 60Co was determined to be 1.45. Conclusion: The cell-killing effects for continuous low-dose-rate (LDR) irradiation by 125I seeds are greater than acute high-dose-rate of 60Co. (authors)

  9. Selective binding of 2-[125I]iodo-nisoxetine to norepinephrine transporters in the brain

    International Nuclear Information System (INIS)

    A radioiodinated ligand, (R)-N-methyl-(2-[125I]iodo-phenoxy)-3-phenylpropylamine, [125I]2-INXT, targeting norepinephrine transporters (NET), was successfully prepared. A no-carrier-added product, [125I]2-INXT, displayed a saturable binding with a high affinity (Kd=0.06 nM) in the homogenates prepared from rat cortical tissues as well as from LLC-PK1 cells expressing NET. A relatively low number of binding sties (Bmax=55 fmol/mg protein) measured with [125I]2-INXT in rat cortical homogenates is consistent with the value reported for a known NET ligand, [3H]nisoxetine. Competition studies with various compounds on [125I]2-INXT binding clearly confirmed the pharmacological specificity and selectivity for NET binding sites. Following a tail-vein injection of [125I]2-INXT in rats, a good initial brain uptake was observed (0.56% dose at 2 min) followed by a slow washout from the brain (0.2% remained at 3 hours post-injection). The hypothalamus (a NET-rich region) to striatum (a region devoid of NET) ratio was 1.5 at 3 hours post-i.v. injection. Pretreatment of rats with nisoxetine significantly inhibited the uptake of [125I]2-INXT (70-100% inhibition) in locus coeruleus, hypothalamus and raphe nuclei, regions known to have a high density of NET; whereas escitalopram, a serotonin transporter ligand, did not show a similar effect. Ex vivo autoradiography of rat brain sections of [125I]2-INXT (at 3 hours after an i.v. injection) displayed an excellent regional brain localization pattern corroborated to the specific NET distribution in the brain. The specific brain localization was significantly reduced by a dose of nisoxetine pretreatment. Taken together, the data suggest that [123I]2-INXT may be useful for mapping NET binding sites in the brain

  10. Microchemical synthesis of the serotonin receptor ligand, /sup 125/I-LSD

    Energy Technology Data Exchange (ETDEWEB)

    Hartig, P.R.; Krohn, A.M.; Hirschman, S.A.

    1985-02-01

    The synthesis and properties of 2-(/sup 125/I)-lysergic acid diethylamide, the first /sup 125/I-labeled serotonin receptor ligand, are described. A novel microsynthesis apparatus was developed for this synthesis. The apparatus employs a micromanipulator and glass micro tools to handle microliter to nanoliter volumes on a microscope stage. This apparatus should be generally useful for the synthesis of radioligands and other compounds when limited amounts of material must be handled in small volumes.

  11. Microchemical synthesis of the serotonin receptor ligand, 125I-LSD

    International Nuclear Information System (INIS)

    The synthesis and properties of 2-[125I]-lysergic acid diethylamide, the first 125I-labeled serotonin receptor ligand, are described. A novel microsynthesis apparatus was developed for this synthesis. The apparatus employs a micromanipulator and glass micro tools to handle microliter to nanoliter volumes on a microscope stage. This apparatus should be generally useful for the synthesis of radioligands and other compounds when limited amounts of material must be handled in small volumes

  12. Preparation and isolation of a homogeneous 125I-cortisol derivative

    International Nuclear Information System (INIS)

    Tracer specificity plays an important role in the radioimmunoassay (RIA) of steroid hormones. In this paper, we describe the preparation and purification of 125I-labeled cortisol derivative with a carboxymethyloxime-histamine bridge. The investigation on the method of purification showed that HPLC could be adopted for the routine preparation of a pure, homogeneous tracer. The retention time observed in HPLC for 125I-histamine-CMO-cortisol conjugate could be used as an index for qualitative and quantitative assessments. (author)

  13. Inhibition effects of 125I-triplex forming oligonucleotide to hepatoma cells

    International Nuclear Information System (INIS)

    Objective: Triplex forming oligonucleotide (TFO) has been reported as a new antigene strategy. The purpose of this study was to observe the inhibition effects of 125I-TFO on hepatoma cells and to investigate the possibility of using 125I-TFO as an antigene radiotherapy technique for hepatocellular carcinoma (HCC) related to HBV. Methods: TFO complementary to the initiator of S gene of HBV was synthesized and labeled with 125I. HepG2.2.15 cells, in which HBV genome was integrated, were incubated with 125I-TFO, TFO and 125I respectively. After incubation, hepatitis B e antigen (HBeAg) and hepatitis B surface antigen (HBsAg) of each group were assayed with ELISA and the survival rate of cells in each group was determined with 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenylte-trazolium bromide (MTT) reduction assay. Results: 125I-TFO showed a high stability with a radiolabeling rate of >93%. The radiochemical purity of labeled compound was 90.8%, 81.1% and 73.2% respectively after 12, 48 and 72 h at 37 degree C. The peak inhibition effect of 125I-TFO on synthesizing HBsAg and HBeAg by HepG2.2.15 cells were found at 48 h after transfection, with significantly the highest inhibition rate of 45.2% for HBsAg and 74.5% for HBeAg expression among the three groups(P125I-TFO may inhibit the antigen expression of HBV and the growth of hepatocarcinoma cells, thus it may provide a new approach to develop gene-based radiotherapeutic pharmaceuticals for anti-HBV and HCC. (authors)

  14. Study on 125I labelling and blood-brain barrier counteracting of calcineurin B

    International Nuclear Information System (INIS)

    Calcineurin B(CNB) is labelled with 125I by iodogen method. The labelling yield is up 85%, the specific activity is 740 GBq·g-1 and the radiochemical purity is 95.7%. The blood-brain barrier counteracting of 125I-CNB is investigated in rats' brain. The results show that blood-brain barrier can counteract intact CNB into brain, but can not counteract its decomposed peptide into brain

  15. Expansão rápida da maxila ancorada em implantes: uma nova proposta para expansão ortopédica na dentadura permanente Rapid maxillary expansion anchored by implants: a new proposal to orthopedic expansion in the permanent dentition

    Directory of Open Access Journals (Sweden)

    Daniela Gamba Garib

    2007-06-01

    Full Text Available OBJETIVO: este trabalho apresenta um método para expansão ortopédica da maxila, na dentadura permanente, utilizando implantes como ancoragem. METODOLOGIA: detalharam-se os procedimentos cirúrgicos e laboratoriais da confecção de um expansor com ancoragem dento-óssea em crânio seco humano. Dois implantes de titânio foram colocados na região anterior do palato, e o parafuso Hyrax adaptado de modo que a expansão ancorou-se nos implantes e nos primeiros molares permanentes. RESULTADOS: o experimento laboratorial em crânio seco mostrou que o procedimento apresenta-se anatômica e operacionalmente viável. Os implantes suportaram a força gerada pela ativação do parafuso expansor, redundando na separação transversal das hemimaxilas. CONCLUSÕES: vislumbra-se que a expansão rápida da maxila ancorada em implantes (ERMAI poderá potencializar a eficiência da expansão ortopédica, assim como reduzir o custo periodontal dos procedimentos convencionais de expansão. Futuros estudos clínicos são necessários para testar essas hipóteses.AIM: This study presents a method for maxillary orthopedic expansion, in the permanent dentition, using implants as anchorage. METHODS: Surgical and laboratorial procedures for the construction of a tooth-bone-borne expansor was detailed in a human dry skull. Two titanium implants were placed in the anterior region of the palate and a Hyrax screw was adapted in a way that the expansion was anchored both on the palatal implants and on permanent first molars. RESULTS: The laboratorial experiment in dry skull showed that the procedure is operationally and anatomically possible. The implants supported the force generated by the expansion screw activation and the maxilla halves were transversally split. CONCLUSIONS: Rapid maxillary expansion anchored on implants can increase the efficiency of orthopedic expansion and decrease the periodontal sequela caused by conventional RME. Further clinical studies are necessary to verify these hypotheses.

  16. Estrogen receptor assay of mammary cancer by 16 alpha-125I-estradiol

    International Nuclear Information System (INIS)

    125I-labeled estradiol (16-?-125I-estradiol-17?) was synthesized from 16-?-Br-estradiol by halogen exchange reaction and purified by high-performance liquid chromatography. The comparative studies of estrogen receptor assays using 125I-E2 and 3H-E revealed that 125I-E2 had the high affinity to cytoplasmic estrogen receptors in rat uteri and human mammary tumor tissues (about 60% of estradiol-17?) and 8S and 4S of estrogen-receptor complexes determined by sucrose density gradient method were identical between 125I-E2 and 3H-E2. The strong coincided rate on the positivity and the negativity of estrogen receptors in human mammary tumor tissues was 97.9% (94/96) and the correlation coefficiency of the binding sites among estrogen receptor assays was r = 0.951 in 41 cases of receptor positive subjects. It made possible to assay estrogen receptor using relatively small amounts of tissues because of the higher radiospecific activity of 125I-E2 than that of 3H-E2. (author)

  17. Radiolabeling of EGCG with 125I and its biodistribution in mice

    International Nuclear Information System (INIS)

    The aim of the present study was to label EGCG with 125I and to determine its radiopharmaceutical potential in mice. EGCG was labeled with 125I using the iodogen method. The labeling yield and the radiochemical purity of 125I-EGCG were determined by radio thin-layer chromatography (RTLC). The Labeling yield was approximately 89.4 %. The radiochemical purity was approximately 96.4 %. The biodistribution studies of the labeled compound (specific activity; 0.47 TBq/?g) were performed in male Kunming mice. The uptakes of 125I-EGCG in some organs were determined at different time after injection to the mice. The radioactivity in each organ was counted and the percentage of injected activity per gram of tissue weight (%ID/g) for each organ and blood was calculated. Incorporation of radioactivity in the various tissue/organ was confirmed by microautoradiography. 125I-EGCG uptake in the stomach and salivary gland was higher than other organ/tissue. The black silver grains was concentrated in the nucleus, cytoplasm, intercellular substance and capillaries of that various organs, and its unevenly distributed. Thus, 125I-EGCG may be radiopharmaceutical for the imaging of the stomach and salivary gland. (author)

  18. Heparin blocks 125I-calmodulin internalization by isolated rat renal brush border membrane vesicles

    International Nuclear Information System (INIS)

    125I-Calmodulin is internalized by isolated rat renal brush border membrane vesicles (BBV) in a time, temperature and calcium dependent manner. Internalization of 125I-calmodulin into the osmotically sensitive space of BBV was distinguished from binding of the ligand to the outer BBV surface by examining the interaction of ligand and BBV at different medium osmolarities (300-1100 mosm), uptake was inversely proportional to medium osmolarity. Internalized 125I-calmodulin was intact and Western blots of solubilized BBV with 125I-calmodulin demonstrated the presence of several calmodulin-binding proteins of 143, 118, 50, 47.5, 46.5 and 35 kilodaltons which could represent potential intravesicular binding sites for the ligand. Heparin and the related glycosaminoglycan heparin sulfate both showed a dose-dependent inhibition (0.5-50 ?g/ml) of 125I-calmodulin uptake by BBV, but other sulfated and nonsulfated glycosaminoglycans including chondroitin sulfates, keratan sulfate and hyaluronic acid showed little or no inhibitory effect. Desulfation of heparin virtually abolished the inhibition of uptake while depolymerization reduced it. Heparin did not block the binding of 125I-calmodulin to BBV proteins as assessed by Western blotting technique suggesting its effect was on internalization of the ligand rather than on its association with internal membrane proteins

  19. Evidence for multiple pathways of 125I-insulin internalization in isolated rat hepatocytes

    International Nuclear Information System (INIS)

    Insulin internalization has been characterized frequently as occurring by the coated pit pathway of receptor-mediated endocytosis. The present study in rat hepatocytes demonstrates that insulin internalization is, in part, receptor-mediated, but also occurs by nonreceptor-mediated or fluid-phase endocytosis. Endocytosis was probed with four perturbations: depletion of metabolic energy with anoxia, inhibition of endocytosis with phenylarsine oxide, disruption of coated pits with hyperosmolar sucrose, and inhibition of receptor recycling or ligand-receptor dissociation with monensin. Internalization of 125I-epidermal growth factor and 125I-asialofetuin was compared to 125I-insulin internalization. Pretreatment of cells with anoxia or hyperosmolarity inhibited 125I-insulin internalization by 40%; pretreatment with phenylarsine oxide resulted in inhibition by 54%. Monensin has no effect on uptake or degradation of a high insulin concentration, but inhibited degradation of a low insulin concentration resulting in intracellular accumulation of insulin. In contract, all four perturbations inhibited 125I-asialofetuin internalization by greater than 90%. Phenylarsine oxide almost completely abolished 125I-epidermal growth factor uptake; the other perturbations caused partial inhibition. Competition studies demonstrated that insulin internalization was receptor-mediated over a wide concentration range

  20. The preparation of 125I-?-CIT and its biological distribution in animal

    International Nuclear Information System (INIS)

    Objective: To prepare and label the 125I-?-CIT and study its biological distribution in animal. Methods: 125I-?-CIT was prepared by the peracetic acid method and the chloramine-T method, and dopamine transporter (DAT) binding properties of 125I-?-CIT were examined by in vivo biodistribution and inhibition studies in mice and whole body autoradiography in rats. Results: The radiolabelling yields of the peracetic acid and the chloramine-T methods were (53.4 +- 7.9)% and (88.4 +- 3.49)%, respectively. Following intravenous injection in mice, 125I-?-CIT showed high accumulation in striatum, time to peak level uptake was 2 h after injection. GBR12909 significantly inhibited 125I-?-CIT binding in striatum, while clomipramine significantly inhibited 125I-?-CIT binding in hippocampus and cerebral cortex. The rat whole body autoradiography showed that the clearance of the tracer occurred through the hepatobiliary route. Conclusions: The results indicate ?-CIT is an agent suitable for DAT imaging and can be used for the study of Parkinson's disease

  1. Study of dose deposition of 125I brachytherapy seeds in a solid water phantom

    International Nuclear Information System (INIS)

    Currently, many kinds of radioactive sources are used in brachytherapy for cancer treatment. The 125I seed used in this work is the model Onco Seed 6711, produced by Oncura, which is ranked among the best options for treating prostate cancer. This source emits gamma photons with average energy of 28 keV and has a half-life of 59.4 days. After the implants, the natural movement of the organ can cause the seeds undergo slight displacements relative to the position originally planned, which can cause changes in dose distribution in the tumor volume. This work seeks to compare the dose distribution in a solid water phantom of two symmetrical, but different arrangements of four seeds. For this study, the phantom was machined to accommodate the seeds and TLD-100 LiF rod type dosimeters. The study, using TLD dosimeters, was conducted up to 4 cm of the settings. In addition, an Ebt Gafchromic radiochromic film was positioned over the two configurations during a period of time enough for 1 Gy deposition on it, to observe possible changes in the shape of the isodose curves. The TLD results showed a difference up to 35.8% of the dose deposited in the center of the configurations and different doses were deposited at distances corresponding to 1 and 2 cm radius from the symmetrical seeds arrangements. After 3 cm radius, the dose discrepancy is no longer significant. Another important point is that despite the configurations are symmetric, different dose values were deposited at symmetrical points. The isodose qualitative curves shown by the films showed a difference in the shape of that curves. Thus, the different positions of the seeds proved decisive in dose deposition and this fact should be taken into consideration in planning treatment

  2. Experimental study on differential diagnosis of tumor from inflammation by using /sup 125/I labeled Pisum sativum agglutinin

    Energy Technology Data Exchange (ETDEWEB)

    Kojima, Shuji; Jay, M.

    1987-12-01

    We have reported that Pisum sativum agglutinin (PSA), a plant lectin which recognizes mannosyl residues, accumulates markedly in Ehrlich solid tumor (EST) and suggested the possibility of applying PSA to tumor imaging radiopharmaceuticals. In the present work, an inflammation was induced by implantation of cotton thread in the left rear leg skeletal muscle of ddY mice and Ehrlich ascites tumor cells were inoculated into the right rear leg. /sup 67/Ga-citrate accumulated in the tumor tissue and the inflammatory lesion to almost equal extents. On the other hand, /sup 125/I-PSA preferentially accumulated in tumor tissues in mice bearing both tumor and inflammation. The results suggest that differential diagnosis of tumor from inflammation using radiolabeled PSA may be possible.

  3. Effect of 1.5 tesla nuclear magnetic resonance imaging scanner on implanted permanent pacemakers.

    Science.gov (United States)

    Hayes, D L; Holmes, D R; Gray, J E

    1987-10-01

    Patients with a permanent pacemaker are currently restricted from diagnostic nuclear magnetic resonance (NMR) imaging because of potential adverse effects on the pacemaker by the magnet. Previous work has shown that NMR imaging will result in asynchronous pacing of the pulse generator within a given distance of the magnet. The radiofrequency signal generated by the system may also result in rapid cardiac pacing, which may have deleterious effects. This study utilized a 1.5 tesla unit in an in vivo laboratory animal to evaluate the unit's effects on eight different pulse generators from two manufacturers. All pacemakers functioned in an asynchronous mode when placed within a certain distance of the magnet. In addition, transient reed switch inhibition was observed. Seven of the eight pulse generators paced rapidly when exposed to the radiofrequency signal and there was a dramatic decrease in arterial blood pressure. Whether effective rapid cardiac pacing would occur could not be predicted before exposure to the magnetic resonance unit. Nuclear magnetic resonance imaging with high magnetic fields in patients with a pacemaker should continue to be avoided until the mechanism of the rapid cardiac pacing can be further delineated and either predicted or prevented. PMID:3655146

  4. Use of brachytherapy with permanent implants of iodine-125 in localized prostate cancer; La curietherapie par implants permanents d'I-125 dans le cancer localise de la prostate

    Energy Technology Data Exchange (ETDEWEB)

    Bladou, F.; Serment, G. [Hopital Salvador, Service d' Urologie, 13 - Marseille (France); Salem, N.; Simonian, M. [Hopital Salvador, Dept. de Radiotherapie, 13 - Marseille (France); Rosello, R.; Ternier, F. [Institut Paoli-Calmettes, Dept. de Radiologie, 13 - Marseille (France)

    2002-07-01

    Approximately 15,000 cases of early stage prostate cancer T1 and T2 are diagnosed every year in France by testing for PSA and performing prostatic biopsies. The treatment of these localized forms is based in most cases on radical prostatectomy or nn external beam radiotherapy. Although the ontological results obtained by these two therapeutic methods are satisfactory and equivalent in the long term, the side effects can be important. For a number of years, trans-perineal brachytherapy using permanent implants of iodine -125 or palladium-103 has proved itself as an alternative therapy with equivalent medium to long-term results. The low urinary, digestive and sexual side effects of prostate brachytherapy are important reasons for the enthusiasm among patients and the medical community for this therapy and the growing number of applications and centres which practice it. In September 1998 we started the prostate brachytherapy programmes- in Marseilles with close collaboration between the department of urology of the Hopital Salvator, and the departments of radiotherapy, medical imaging and medical physics of the Institut Paoli-Calmettes. To date, around 250 patients with localized adenocarcinoma of the prostate have benefited from this alternative therapy in our centre. Preliminary results, with a 3 year-follow-up, are comparable to results published in the literature by pioneer teams. (authors)

  5. Dose rate distribution on cultured cell exposed to 125I seed in vitro irradiation

    International Nuclear Information System (INIS)

    Objective: To study the dose rate distribution on cultured cell plane and establish a reference dose rate table of in vitro cell line 125I seed irradiator. Methods: Thermoluminescence dosimetry (TLD) was used to measure the irradiation dose rate of a single 6711 model 125I seed with apparent activity of 10.323 MBq in water at point P. Meanwhile, the theoretic value of the irradiation dose rate at point P was calculated with theoretic formula. The difference between the calculated and observed values within 10% was set as standard to analyze the accuracy of the measurement. The irradiation dose rate ora single 6711 model 125I seed was measured in 1 mm- thick polystyrene + water medium at point P. The value was applied to differential m non-differential proof along with the value from water medium to study the effect of 1 mm thick polystyrene on distribution of irradiation dose in water. Finally, by simulating the 125I seed plane irradiator with nine 125I seeds, the distribution table of irradiation dose rate on the cultured cell plane was calculated with theoretical formula. Results: The observed value (n 10) of irradiation dose rate with one 125I seed in water at point P was(0.359 ± 0.023) eGy/h and the calculated value was 0.347 cGy/h, the difference was within 10%. The observed value (n=10) of irradiation dose of one 125I seed in 1 mm-thick polystyrene + water medium at point P was (0.350±0.027) cGy/h, which showed no statistical difference from the observed value in water under differential and non-differential proof. The reference table on dose rate distribution for cells exposed to 125I seed irradiation in vitro was developed. Conclusions: 1 mm-thick polystyrene gives no significant effect on irradiation dose rate distribution flora 125I seeds in water. A reference table on the dose rate distribution for cells exposed to 125I seed irradiation in vitro has been developed, which can be used to determine an optimal irradiating strategy for future work. (authors)

  6. DNA strand breakage by 125I-decay in oligoDNA

    International Nuclear Information System (INIS)

    Full text: A double-stranded oligodeoxynucleotide containing 125I-dC in a defined location, with 5'- or 3'-32P-end-labelling of either strand, was used to investigate DNA strand breakage resulting from 125I decay. Samples of the 32P-end-labelled and 125I-dC containing oligoDNA were incubated in 20 mM phosphate buffer (PB), or PB + 2 M dimethylsulphoxide (DMSO) at 4 deg during 18-20 days. The 32P-end-labelled DNA fragments produced by 125I decays were separated on denaturing polyacrylamide gels, and the 3P activity in each fragment was determined by scintillation counting after elution from the gel. The fragment size distribution was then converted to a distribution of single stranded break probabilities at each nucleotide position. The results indicate that each 125I decay event produces at least one break in the 125I-dC containing strand, and causes breakage of the opposite strand in 75-80% of events. Thus, the double stranded break is produced by 125I decay with probability ?0.8. Most of single stranded breaks (around 90%) occurred within 5-6 nucleotides of the 125I-dC, however DNA breaks were detected up to 18-20 nucleotides from the decay site. The average numbers of single stranded breaks per decay are 3.7 (PB) and 3.3 (PB+DMSO) in 125I-dC containing strand, and 1.5 (PB) and 1.3 (PB+DMSO) in the opposite strand. Deconvolution of strand break probabilities as a function of separation from the 125I, in terms of both distance (to target deoxyribosyl carbon atoms, in B-DNA) and nucleotide number, show that the latter is an important parameter for the shorter-range damage. This could indicate a role for attenuation/dissipation of damage through the stacked bases. In summary, the results represent a much more extensive set of data than available from earlier experiments on DNA breakage from l25I-decay, and may provide new mechanistic insights

  7. Plasmid DNA breakage by decay of DNA associated isotopes 123I and 125I

    International Nuclear Information System (INIS)

    The biological consequences of decay of DNA-associated 125I have been extensively investigated using a variety of systems. It is well established that decay of the isotope in close proximity to DNA produces a DSB with an efficiency close to 1. Much less information is available for another iodine isotope - 123I. It is a 'weaker' Auger emitter than 125I, and has much shorter half-life; 13.2 hours compared to 60 days for 125I. Cell culture studies indicate that decay of 123I is more than two times less efficient in killing V79 cells than decay of 125I, and produces from 0.45 to 0.74 DSB per decay in the cell nucleus. The Monte Carlo simulation of 123I decay and DSB induction has generated a value of 0.4 DSB per decay of incorporated isotope. We have adapted the plasmid DNA assay to compare strand breakage by decay of DNA-associated 125I and 125I, exploiting DNA minor groove binding ligand Hoechst 33258 labelled with either of these isotopes. Application of the plasmid assay to this study highlighted a range of important factors, which were taken into account to ensure a valid outcome. These factors involve the statistical implications of the nature of the breakage events (such as multiple breaks arising from a single decay event), two different sources of damage, namely internal (from DNA-associated decay events) and external (from decays occurring anywhere in solution), and consideration of the fraction of DNA-bound ligand. In our experiments, we incubated pBR322 plasmid with [125I]-iodoHoechst 33258 or with mixture of ligands labelled with 123I and 125I. The latter approach allows measurement of the ratio of probabilities of DSB formation per decay for the two isotopes, with much higher precision than determination of the individual breakage probabilities for each isotope. We obtained for the probability (per decay) of induction of DSB by the 125I-labeled ligand a value of 0.82 ± 0.05. Inclusion of DMSO as a radical scavenger, reduces this value to 0.65 ± 0.05 DSB per decay. The ratio of DSB probability per decay of 123I to that of 125I is 0.63 ± 0.03, with little change with inclusion of DMSO; namely to 0.65 ± 0.03

  8. Expansão rápida da maxila ancorada em implantes: uma nova proposta para expansão ortopédica na dentadura permanente / Rapid maxillary expansion anchored by implants: a new proposal to orthopedic expansion in the permanent dentition

    Scientific Electronic Library Online (English)

    Daniela Gamba, Garib; Ricardo de Lima, Navarro; Carlos Eduardo, Francischone; Paula Vanessa Pedron, Oltramari.

    2007-06-01

    Full Text Available OBJETIVO: este trabalho apresenta um método para expansão ortopédica da maxila, na dentadura permanente, utilizando implantes como ancoragem. METODOLOGIA: detalharam-se os procedimentos cirúrgicos e laboratoriais da confecção de um expansor com ancoragem dento-óssea em crânio seco humano. Dois impla [...] ntes de titânio foram colocados na região anterior do palato, e o parafuso Hyrax adaptado de modo que a expansão ancorou-se nos implantes e nos primeiros molares permanentes. RESULTADOS: o experimento laboratorial em crânio seco mostrou que o procedimento apresenta-se anatômica e operacionalmente viável. Os implantes suportaram a força gerada pela ativação do parafuso expansor, redundando na separação transversal das hemimaxilas. CONCLUSÕES: vislumbra-se que a expansão rápida da maxila ancorada em implantes (ERMAI) poderá potencializar a eficiência da expansão ortopédica, assim como reduzir o custo periodontal dos procedimentos convencionais de expansão. Futuros estudos clínicos são necessários para testar essas hipóteses. Abstract in english AIM: This study presents a method for maxillary orthopedic expansion, in the permanent dentition, using implants as anchorage. METHODS: Surgical and laboratorial procedures for the construction of a tooth-bone-borne expansor was detailed in a human dry skull. Two titanium implants were placed in the [...] anterior region of the palate and a Hyrax screw was adapted in a way that the expansion was anchored both on the palatal implants and on permanent first molars. RESULTS: The laboratorial experiment in dry skull showed that the procedure is operationally and anatomically possible. The implants supported the force generated by the expansion screw activation and the maxilla halves were transversally split. CONCLUSIONS: Rapid maxillary expansion anchored on implants can increase the efficiency of orthopedic expansion and decrease the periodontal sequela caused by conventional RME. Further clinical studies are necessary to verify these hypotheses.

  9. Effectiveness of the I-125 seed permanent implant for localized prostate cancer with the intraoperative planning technique. Comparison with pre-planning technique

    International Nuclear Information System (INIS)

    The purpose of this study was to report the effectiveness of the I-125 seed permanent implantation for localized prostate cancer with an intraoperative planning method. With one retrospectively compared the two techniques using post-implant CT-based evaluations: a pre-planning method and an intraoperative planning method. Two hundred forty four patients with T2b or less localized prostate cancer underwent the permanent seed implant between September 2003 and March 2006. One hundred twenty two patients were treated with a pre-planning method while the other half patients were treated with an intraoperative planning. Baseline parameters closely resemble in both groups. However, there were important differences in preoperative prostate volume, source activities, needles and operation time of both groups. Based on a month post-implant CT, patients treated with the pre-planning method marked 155.3 Gy in median prostate D90 (minimal dose covering 90% of the prostate volume) and 92.1% in V100 (percent prostate volume receiving 100% of the prescribed dose). While the intraoperative group marked 169.4 Gy and 97.1%, respectively (p<0.01). Prostate D90 and V100 in the intraoperative group was noted as meaningful improvement. Postoperative dosimetry of the urethra and the rectum followed and conducted as planned. Seed implantation with an intraoperative planning method was more effective than the one with a preoperative planning method. We plan to expand its use of the treatment in the future. (author)

  10. A novel 125I-labeled daunorubicin derivative for radionuclide-based cancer therapy

    International Nuclear Information System (INIS)

    Introduction: Auger electron emitters, such as 125I, are getting increasingly wider recognition as alternatives to current anticancer treatments. The effectiveness of Auger electrons is strongly dependent on their proximity to DNA and is therefore considered as harmless outside the nucleus. Methods: 125I or 127I was conjugated with Comp1, Comp2 or Comp3 - three derivatives of the chemotherapeutic drug daunorubicin. Their capacity factors, DNA-binding constants and exclusion parameters, and the degree of DNA fragmentation after incubating isolated DNA with our 127I- or 125I-conjugated daunorubicin derivatives were determined. Human breast adenocarcinoma (SK-BR-3) cells were incubated with the derivatives; fluorescent microscopy and autoradiography images were generated; and cell growth was monitored. Results and Discussion: The capacity factor of 127I-Comp1 was similar to those of daunorubicin and doxorubicin, whereas lower capacity factors of 127I-Comp2 and 127I-Comp3 suggested reduced interactions with lipid membranes. DNA exclusion parameters and binding constants of 127I-Comp1 and 127I-Comp2, but not of 127I-Comp3, were similar to those of doxorubicin. Fluorescent microscopy and autoradiography images of SK-BR-3 cells revealed that 127I-Comp1 and 125I-Comp1 accumulated in tumor cell nuclei, whereas 127I-Comp2 and 127I-Comp3 were present predominantly in other cell compartments. The binding of 125I-Comp1 to isolated chromosomal DNA led to major fragmentation. Incubation of SK-BR-3 cells with 125I-Comp1 inhibited cell growth, whereas doxorubicin or 127I-Comp1 administered at the same concentration had no effect on cell growth. Our results thus suggest that 125I-Comp1 has the potential to become a new tool for anticancer therapy

  11. Study on preparation and brain distribution of 125I-?-CIT

    International Nuclear Information System (INIS)

    Objective: To develop a relatively simpler and faster method for the routine preparation of 125I-?-CIT and animal brain distribution of 125I-?-CIT. Methods: Peracetic acid or Iodogen as an oxidant was used to prepare 125I-?-CIT and comparison was made between them. The HPLC purification technique was used to identify the labeled tracer. Stability and safety of the radioiodinated ?-CIT were also studied. Groups of mice (n=5) were injected i.v. into the tail vein with 125I-?-CIT . Animals were killed at 5, 15, 30 and 45 minutes, and 1, 2, 4, 6, 8 and 24 hours. Autoradiography was performed on brains of mice at 4 hours after injection. Results: Two kinds of labeling methods using Iodogen or peracetic acid produced 125I-?-CIT of radiochemical yields 91.10% ± 8.09%, 54.70 ± 9.81% respectively, with high radiochemical purity (RCP) 99.33% ± 0.15%, 18-25 degree C and pH 1 or 2 is the best for Iodogen preparation. The labeled product was stable for at least 23 days when kept in room temperature, and stable for at least 10 weeks when kept in -4 degree C refrigerator. The peak time of uptake of 125I-?-CIT in striatum was at four hours after injection and the highest value was 22.93% ± 3.11% ID/g. It's highest uptake rate is 20.09 ± 2.11. Conclusions: The Iodogen preparation method is simpler and has a higher labeling yield than peracetic acid labeling method and the labeling yield is higher than which ever reported abroad. The labeled radiopharmaceutical is stable. 125I-?-CIT showed the highest accumulation in striatum with high densities of dopamine transporters in brain

  12. Autoradiographic localization of putative nicotinic receptors in the rat brain using 125I-neuronal bungarotoxin

    International Nuclear Information System (INIS)

    Neuronal bungarotoxin (NBT), a snake venom neurotoxin, selectively blocks nicotinic receptors in many peripheral and central neuronal preparations. alpha-Bungarotoxin (alpha BT), on the other hand, a second toxin isolated from the venom of the same snake, is an ineffective nicotinic antagonist in most vertebrate neuronal preparations studied thus far. To examine central nicotinic receptors recognized by NBT, we have characterized the binding of 125I-labeled NBT (125I-NBT) to rat brain membranes and have mapped the distribution of 125I-NBT binding in brain sections using quantitative light microscopic autoradiography. The binding of 125I-NBT was found to be saturable, of high affinity, and heterogeneously distributed in the brain. Pharmacological studies suggested that more than one population of sites is labeled by 125I-NBT. For example, one component of 125I-NBT binding was also recognized by alpha BT, while a second component, not recognized by alpha BT, was recognized by the nicotinic agonist nicotine. The highest densities of these alpha BT-insensitive, nicotine-sensitive sites were found in the fasciculus retroflexus, the lateral geniculate nucleus, the medial terminal nucleus of the accessory optic tract, and the olivary pretectal nucleus. alpha BT-sensitive NBT binding sites were found in highest density in the lateral geniculate nucleus, the subthalamic nucleus, the dorsal tegmental nucleus, and the medial mammillary nucleus (lateral part). The number of brain regions with a high density of 125I-NBT binding sites, blocked either by alpha BT or by nicotine, is low when compared with results obtained using other approaches to studying the central distribution of nicotinic receptors, such as labeling with 3H-nicotine or labeling with cDNA probes to mRNAs coding for putative receptor subunits

  13. Cetuximab affects the capacity of DNA repair in colorectal cancer cells after 125I seeds irradiation

    International Nuclear Information System (INIS)

    Objective: To investigate the effect of C225 on DNA repair and molecular pathways in CL187 colorectal cancer cells after irradiated by 125I radioactive seeds. Methods: In the experiment involved were four groups:control group, 100 nmol/L C225 treatment group,125I radioactive seeds continuous low-dose rate irradiation group and C225 combined with 125I radioactive seeds continuous low dose rate irradiation group. Cells were collected at 48 h after 4 Gy irradiation, and ?H2AX foci/cell and ?H2AX foci positive cells were counted with immunofluorescence. At the same time, DNA repair proteins were detected by Western blot. Cells were analyzed immediately after 4 Gy irradiation,and changes in EGFR downstream signaling molecules were detected by Western blot. Results: Compared with 125I seeds irradiated cells,cells treated with C225 and 125I seeds irradiation showed more ?H2AX foci per cell (t=8.0, P=0.05), and more ?H2AX foci positive cells (t=6.8, P<0.05) and less expression of Ku70 (t=6.6, P<0.05) and DNA-PKcs (t=5.6, P<0.05). Combined with 125I-CLDR irradiation, C225 reduced cellular EGFR level (t=4.9, P<0.05) and inhibited the activation of Akt (t=5.5, P<0.05). Conclusions: In the condition of 125I seeds irradiation, C225 reduced the expression of Ku70 and DNA-PKcs, inhibited the activation of Akt and attenuated the DNA damage repair capacity in CL187 colorectal cancer cells. (authors)

  14. Analysis of prostate-specific antigen bounce after I125 permanent seed implant for localised prostate cancer

    International Nuclear Information System (INIS)

    Background and purpose: To report on the incidence of benign prostate-specific antigen bounce following permanent I125 prostate brachytherapy, to describe the associations in our population and review the relationship of bounce to subsequent biochemical failure. Materials and methods: From February 2000 to May 2005, 374 patients with localised prostate cancer were treated with I125 permanent prostate brachytherapy at a single institution. A prospectively collected database was used to identify cases of prostate-specific antigen (PSA) bounce, defined as a rise of ?0.2 ng/ml above an initial PSA nadir with subsequent decline to or below that nadir without treatment. The patients who received neo-adjuvant or adjuvant hormone manipulation were excluded. Biochemical failure was determined using the both the ASTRO consensus definition and Phoenix (nadir +2 ng/mL) definition. Results: Two hundred and five patients were identified with a median follow-up of 45 months (24-85). PSA bounce was noted in 79 (37%) men, occurring at a median of 14.8 months (1.7-40.6) following implant. The median peak PSA was 1.8 ng/ml (0.4-7.4) with a bounce magnitude of 0.91 ng/ml (0.2-5.8). When pre- and post-implant factors were assessed for association to bounce, only younger age was statistically significant (p = 0.002). The threshold for biochemical failure as defined by the ASTRO consensus definition (1997) was met in 4 (5%) patients after experiencing bounce as opposed to 19 (15%) non-bounce patients (p = 0.01). The threshold for Phoenix (nadir +2 ng/mL) was met in 6 (7.5%) patients following bounce versus 22 (17%) of non-bounce patients (p = 0.003). Both definitions are prone to false positive calls during bounce. Median PSA velocity during the bounce was 0.08 ng/mL/month (0.02-0.98) and was statistically significantly lower than the median velocity prior to the Phoenix biochemical failure at 0.28 ng/mL/month (0.07-2.04) (p = 0.0005). Conclusion: PSA bounce is a common finding in our population and is associated with a lower rate of subsequent biochemical failure. The noted differences in PSA velocity will require verification in a future analysis to reduce the influence of median follow-up on this finding. Patients should be advised of the potential of bounce in PSA follow-up after permanent I125 prostate brachytherapy and physicians involved in follow-up of prostate brachytherapy patients should be aware of this phenomenon, allowing them to commit to appropriate PSA surveillance, avoiding the premature and inappropriate initiation of salvage therapy during PSA bounce

  15. In vitro characterization of the influx of 3-[125I]iodo-L-?-methyltyrosine and 2-[125I]iodo-L-tyrosine into U266 human myeloma cells: Evidence for System T transport

    International Nuclear Information System (INIS)

    The aim of this study was to investigate the cellular uptake mechanisms responsible for the accumulation of 3-[125I]iodo-L-?-methyltyrosine (125I-3-IMT) and 2-[125I]iodo-L-tyrosine (125I-2-IT), two radiotracers for metabolic tumor imaging, using single-photon emission tomography, into U266 human myeloma cancer cells. Time course and concentration dependency of 125I-3-IMT uptake was assessed. Kinetic parameters were calculated using an Eadie Hofstee plot. A set of competitive inhibitors of the main amino acid transport systems was used for the discrimination of the transporters responsible for the uptake of 125I-3-IMT and 125I-2-IT. Protein incorporation of both tracers was determined using acid precipitation. The measured maximum velocity for 125I-3-IMT transport was 4.199 nmol per mg protein 20 s-1, and the Michaelis constant was 107.9 ?M. Addition of 2-aminobicyclo[2,2,1]heptane-2-carboxylic acid (BCH), a competitive inhibitor of System L, reduced the influx by 39.0±3.3% for 125I-3-IMT and 66.3±0.9% for 125I-2-IT. The BCH-insensitive influx was further reduced by Tryptophan (Trp) by 43.8±3.5% for 125I-3-IMT and 15.3±1.3% for 125I-2-IT. This suggests involvement of System T transport. We measured 125I-3-IMT and 125I-2-IT into U266 human myeloma cells is mediated by both System L and System T amino acid transporters. The kinetic parameters suggest that elevated plasma levels of aromatic amino acids will reduce 123I-3-IMT uptake in myeloma patients. Both tracers do not enter protein synthesis significantly

  16. Clinical and physical determinants for toxicity of 125-I seed prostate brachytherapy

    International Nuclear Information System (INIS)

    Background and purpose: To assess acute as well as long-term toxicity after permanent prostate seed implantation. To find predictive clinical or dosimetric factors for side effects in order to work out strategies for improvement. Patients and methods: A group of 174 patients with localised prostate cancer was treated with permanent seed implantation between 1999 and 2001, either alone (140 patients) or in combination with external radiotherapy (34 patients). For the majority (114/174, i.e. 66%) a CT was performed four weeks after implantation and analysed in the planning system VariSeed. In the postimplant analysis, dosimetric descriptors (doses, volumes) were determined for the prostate and rectum and compared with the intraoperative values. In addition, a questionnaire was sent to all patients to assess and quantify acute and chronic toxicity (urinary, rectal, sexual) and the impact on subjective acceptance and quality of life (return rate of questionnaires 83%). The derived score changes were correlated with clinical and dosimetric factors. Results: In the mono-brachytherapy group 14% (16/140) required a bladder catheter, of them 8% (9/140) with a manifest urinary obstruction. Long-term rectal toxicity (50>240 Gy), which appears to be attributed to unnecessarily high numbers of seeds (for a fixed activity per seed) and needles. The rectal toxicity is correlated with the high dose regions in the rectum (?145 Gy). Urinary toxicity is lower for combined-brachytherapy, while rectal toxicity and impairment of potency are slightly higher. Conclusions: Toxicity spectrum and quality of life after permanent seed implantation for early prostate cancer are acceptable for nearly all patients (98%). To further improve tolerance we should attempt to achieve a better dose homogeneity, i.e. by reducing D50. Therefore, special attention should be given to D50 during the real-time planning process. The necessity of more homogeneous dose distributions might imply a reduction of the activity per seed, e.g. from 0.7 mCi down to 0.6 mCi

  17. Development of miniature 125I sources for the treatment of eye and prostate cancers

    International Nuclear Information System (INIS)

    The aim of the present work was to develop a technology for the fabrication of 125I brachytherapy sources for their potential application in the treatment of eye and prostrate cancers. Several methods of incorporating the 125I activity in solid core were investigated and the best among them, in terms of low leachability, ease of preparation and encapsulation in titanium capsules and reproducibility was chosen. Two kinds of cores, namely rod/cylinder shaped wires and spherical balls, were envisaged for introduction into the titanium capsule. Two procedures for depositing the 125I activity on rod shaped core were explored; namely anodic deposition of 125I on silver wire and physicochemical adsorption of 125I on palladium chloride coated silver wire. Similarly, two methods for depositing 125I on spherical source cores were studied. In the first case, alumina microspheres were used as the core on which 125I was impregnated as iodate (IO-3) using a solid-solution interface technique. In the second, 125I was adsorbed on palladium coated silver beads of 0.5 mm. Various physical and chemical parameters were optimized to obtain quantitative uptake of 125I and firm adsorption that would result in negligible iodine leachability (? 0.01%). The source cores prepared by various methods were encapsulated in indigenously fabricated titanium capsules [4.5mm (l) 0.8mm (OD) and 0.05mm (thickness)]. These capsules were in accordance with the ISO specifications for use as low energy brachytherapy sources. The welding of the capsules was optimized by changing welding parameters such as energy, frequency and pulse duration to obtain neat and leak-proof welded capsules. Integrity of the welding was ascertained by metallographic examination and leak testing. Quality assurance tests such as leak testing and dosimetry that are essential before clinical use were conducted. All the above methods were compared and the one which was easy to prepare in large scale was adopted for preparation of the sources for clinical trials. (author)

  18. Synthesis and biodistribution of [125I]iodo- and [75Se]seleno-ergoline derivatives

    International Nuclear Information System (INIS)

    ([125]Iodomethyl)-6-propylergoline (125I-3) was prepared by refluxing the mesyl analog with Na125I in methyl-ethyl-ketone, followed by HPLC, in a radiochemical yield greater than 70%. [75Se]Selenopergolide (75Se-2) was prepared in 74% yield starting with H275 SeO3. The biodistribution studies of the two compounds in male rats show good uptake by the adrenals and the brain. Compound 75Se-2 had higher adrenal uptake and adrenal-to-blood ratios (4.2% dose/g and 70:1) than 125I-3 (3.6% dose/g and 23.8:1) at 15 min post injection. The two compounds had almost equal brain uptake (0.91% dose/g for 75Se-2 and 1.14% dose/g for 125I-3), but 75Se-2 showed higher brain-to-blood ratios (15.2:1 vs 7.3:1) at 15 min post injection. This study indicates that 75Se-2 and 125I-3 may be useful agents for imaging the adrenal and the brain. (author)

  19. Synthesis of 125 I - Salicyl Hydroxamic Acid for Urinary Bladder Imaging

    International Nuclear Information System (INIS)

    Salicylhydroxamic acid is a salicylate derivative. Radiolabeling of Salicyl hydroxamic acid ( SHA ) with iodine-125 may have considerable interest for imaging of urinary bladder. This study is aimed to optimize the radiolabeling yield of Salicyl hydroxamic with radio iodine (125-123) using chloramine - T (CAT) as an oxidizing agent with respect to factors that affect the reaction conditions such as SHA amount, CAT amount, reaction time and ph of the reaction mixture. In - vitro stability of the radiolabeled complex was checked and it was found to be stable for up to 24 h. 125 I-SHA was injected via intravenous administration routes into normal male Sprague – Dawley rats. Bio - distribution studies have revealed that 125I-SHA was excreted in urine with extent that it could give a clear image for urinary bladder especially if the bladder it tightly closed. The amount of 125 I - Salicyl hydroxamic excreted was increased in case of giving potassium bicarbonate to rat before injection of 125 I-SHA. The result of biodistribution study of 125 I - SHA in experimental animal suggest ed the possibility of using 123 I-SHA to image the urinary bladder

  20. {sup 125}I-iomazenil-benzodiazepine receptor binding during psychological stress in rats

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    Fukumitsu, Nobuyoshi; Tsuchida, Daisuke; Ogi, Shigeyuki; Uchiyama, Mayuki; Mori, Yutaka [Jikei Univ., Tokyo (Japan). School of Medicine

    2002-05-01

    We investigated the changes in {sup 125}I-iomazenil ({sup 125}I-IMZ) benzodiazepine receptor (BZR) binding with psychological stress in a rat model. Six male Wistar rats were placed under psychological stress for 1 hour by using a communication box. No physical stress was not received. 1.85 MBq of {sup 125}I-IMZ was injected into the lateral tail vein and the rat was killed 3 hours later. Twenty-micormeter-thick sections of the brain were collected and % injected dose per body weight (% ID/BW) of eleven regions (frontal, parietal, temporal, occipital cortices, caudate putamen, accumubens nuclei, globus pallidus, amygdala, thalamus, hippocampus and hypothalamus) were calculated by autoradiography. The %ID/BW of rats which were placed under psychological stress was compared with that of 6 control rats. The %ID/BW of rats which were placed under psychological stress diffusely tended to show a reduction in {sup 125}I-IMZ-BZR binding. A significant decrease in BZR binding was observed in the hippocampus of the rats which were placed under psychological stress. {sup 125}I-IMZ-BZR binding tended to decrease throughout the brain. (author)

  1. Uptake and binding of 125I-calmodulin by isolated rat renal brush border membrane vesicles

    International Nuclear Information System (INIS)

    The authors have investigated the interaction of 125I-calmodulin with isolated rat renal brush border membrane vesicles (BBV) using an experimental protocol which allows us to distinguish between ligand binding to the outside of the vesicles vs. uptake and possible binding to the vesicle interior. By examining the association of 125I-calmodulin with BBV as a function of medium osmolarity (300-1100 mosm) to alter intravesicular space, virtually all ligand interaction with BBV was found to represent uptake of intact 125I-calmodulin into the intravesicular space. Uptake appeared specific by the following criteria: (1) it was largely calcium dependent (2) it was inhibited in a dose dependent fashion by calmodulin and the homologous protein troponin C, but not by unrelated proteins (lysozyme, cytochrome C, insulin) (3) it was inhibited by known calmodulin antagonists (calmidazolium, mellitin, trifluoperazine). Calmodulin uptake may be followed by binding of 125I-calmodulin to intravesicular BBV proteins; calmodulin-binding proteins in BBV with molecular weights of 143K, 118K, 50K, 47.5K, 46.5K and 35K were identified by Western blotting techniques. The specific association of 125I-calmodulin with isolated BBV is of interest in regard to the possible role of this calcium regulatory protein in the protein reabsorptive and ion transport functions of this renal tubular membrane fraction

  2. Separation of 134Cs and 137Cs from 125I solution for medical applications

    International Nuclear Information System (INIS)

    While neutron irradiation of natural Xe gas followed by wet chemical dissolution of activation products constitutes a successful paradigm for the small scale production 125I, the concomitant production of 134Cs and 137Cs emerged as the primary impediment which necessitates purification of 125I solution. This paper describes an ion-exchange chromatographic technique using Resorcinol Formaldehyde (RF) resin to purify 125I solution from 134Cs and 137Cs impurities. A thorough investigation of the adsorption parameters of RF resin was carried out to arrive at the experimental conditions resulting optimum retention of 134Cs and 137Cs impurities. Based on the experimental findings, an optimized separation procedure was developed in which the neutron irradiated dissolved products at pH ? 13 was passed through a chromatography column containing RF resin where in 134Cs and 137Cs impurities gets adsorbed leaving behind 125I to appear in the effluent. The overall recovery of 125I was >90% with acceptable purity amenable for clinical applications.

  3. 125I-iomazenil-benzodiazepine receptor binding during psychological stress in rats

    International Nuclear Information System (INIS)

    We investigated the changes in 125I-iomazenil (125I-IMZ) benzodiazepine receptor (BZR) binding with psychological stress in a rat model. Six male Wistar rats were placed under psychological stress for 1 hour by using a communication box. No physical stress was not received. 1.85 MBq of 125I-IMZ was injected into the lateral tail vein and the rat was killed 3 hours later. Twenty-micormeter-thick sections of the brain were collected and % injected dose per body weight (% ID/BW) of eleven regions (frontal, parietal, temporal, occipital cortices, caudate putamen, accumubens nuclei, globus pallidus, amygdala, thalamus, hippocampus and hypothalamus) were calculated by autoradiography. The %ID/BW of rats which were placed under psychological stress was compared with that of 6 control rats. The %ID/BW of rats which were placed under psychological stress diffusely tended to show a reduction in 125I-IMZ-BZR binding. A significant decrease in BZR binding was observed in the hippocampus of the rats which were placed under psychological stress. 125I-IMZ-BZR binding tended to decrease throughout the brain. (author)

  4. N-iodoacetyltyramine: Preparation and use in 125I labeling by alkylation of sulfhydryl groups

    International Nuclear Information System (INIS)

    Preparation and use of N-iodoacetyltyramine in generation of 125I-labeled compounds is described. The kinetics of alkylation of N-acetylcysteine by N-iodoacetyltyramine (k2 = 3.0 M-1 s-1) and N-chloroacetyltyramine (k2 = 0.12 M-1 s-1) indicate that N-iodoacetyltyramine is more useful for labeling sulfhydryl-containing compounds to high specific activity with 125I. Conditions for preparation of carrier-free 125I-labeled N-iodoacetyl-3-monoiodotyramine in 50% yield based on starting iodide are described. The high degree of group specificity of N-iodoacetyl-3-monoiodotyramine reaction with sulfhydryl groups is demonstrated by the high reactivity toward sulfhydryl-containing bovine serum albumin and low reactivity toward N-ethylmaleimide-blocked bovine serum albumin and IgG. 125I-labeled N-iodoacetyl-3-monoiodotyramine was also used to prepare an 125I-labeled ACTH derivative that retains full biological activity, further demonstrating the selectivity toward reactions with sulfhydryl groups

  5. Studies with encapsulated 125I sources. I. Apparatus and dosimetry for determination of relative biological effectiveness

    International Nuclear Information System (INIS)

    Apparatus and dosimetry techniques have been developed which make possible studies of the biological effects of radiation from encapsulated 125I sources at clinically relevant dose rates using mammalian cells attached to culture dishes. The variation of dose rate from 125I photons as a function of distance from the interface between different materials was investigated. A polystyrene substrate changes the mean dose rate in attached cells by about 21%, depending on cell thickness. To reduce dosimetry uncertainty caused by this effect, special petri dishes were made from polyvinylidene fluoride, which changes the mean dose in attached cells by only 10%. Chinese hamster ovary cells attached to these dishes were cultured in incubators which contained 125I and 137Cs sources, allowing the effects of various dose rates (.005 to 0.80 Gy/hr) of radiation from the two isotopes to be compared. The relative dose rates from these low- and high-energy photons were measured with an accuracy of +/- 7% or better using an air-equivalent ionization chamber designed to resemble one of our special petri dishes. Calculations of dose rates from 125I give values within 4% of the measured dose rates used to determine the relative biological effectiveness of 125I photons

  6. Study on 125I-vascular endothelial growth factor receptor-3 polyclonal antibody biodistribution in rat

    International Nuclear Information System (INIS)

    Objective: To study the biodistribution of 125I-Flt4 PcAb in rat and to establish the foundation of sentinel lymph node (SLN) exceptional orientation. Methods Fh4 PcAb was labeled with 125I via chloramine T method, 125I-Flt4 PcAb was subcutaneous injected in dorsum of foot in rats. The rats were killed at different stages after injection and the popliteal lymph nodes and major organs were taken out, then the radioactivity count of those organs and lymph nodes were measured. Results: The labeling efficiency was 46.5%. The specific activity and the radiochemical purity of 125I-Flt4 PcAb were 1.72 x 1012Bq/g and 96.7% respectively. It showed higher distribution in popliteal lymph nodes and blood than the other organs. The radioactivity ratio of popliteal lymph node to blood was more than 2.5 in 16 hours after injection. Conclusions: (1) It was successful to label Flt4 PcAb with 125I via chloramine T method. (2) Flt4 PcAb would concentrate in lymph node after subcutaneous injection. (3) This study provided experimental basis for SLN exceptional orientation with Fh4 PcAb. (authors)

  7. In vivo autoradiographic benzodiazepine receptor imaging with 125I-Iomazenil (Ro 16-0154)

    International Nuclear Information System (INIS)

    The biodistribution of 125I-Iomazenil (Ro 16-0154), a benzodiazepine receptor antagonist, was examined using in vivo autoradiography of gerbil brain. 125I-Iomazenil was administrated i.v. into male gerbils, and autoradiography was prepared from coronary sections of the animals decapitated at 5, 60, 120 and 180 min after injection. Initial uptake images (5 min) of 125I-Iomazenil were thought to show blood flow distribution. On the images obtained 120-180 min after administration, high activity of 125I-Iomazenil was observed in the cerebral cortex, amygdala, hippocampus, globus pallidus, thalamus, hypothalamus, superior colliculus, substantia nigra and cerebellar cortex in the areas of which benzodiazepine receptor concentration was reported to be high. However, low activity was observed in the caudate-putamen. Accumulation of 125I-Iomazenil was blocked by pre-administration of flumazenil. 123I-Ro 16-0154 has a high potentiality for benzodiazepine receptor mapping by SPECT. (author)

  8. Studies of the distribution of intrathecally injected 125I-tetanus antitoxin-F(ab')2

    International Nuclear Information System (INIS)

    Overall F(ab')2 and antitetanus-f(ab')2 - fragments were labelled with 125I and injected i.th. into normal juvenile cats and adult rats. One group of rats was normal; in the other, unilateral local tetanus had been induced by injection of tetanus toxin into a M. gastrocnemius. The animals were sacrificed 24 h after the i.th. injection, and tissue samples were taken for histoautoradiography. 125I-antitetanus-F(ab')2 permeated into the extracellular space of the spinal cord, roots, and ganglia but not into the neuronal intracellular space. 125I-overall-F(ab') showed identical permeation behaviour. 125I-antitetanus-F(ab')2 reacted with tetanus toxin issuing from the motoneurons after i.th. injection, forming an immunocomplex around the motorneurons. The immunocomplex was not formed around pseudo-unipolar ganglian cells in the spinal ganglia even though some of the ganglian cells contained tetanus toxin, and 125I-antitetanus-F(ab')2 was present in the extracellular space. As an explanation, it was suggested that tetanus toxin does not permeate into the extracellular space through the membrane of the pseudo-unipolar ganglian cells so that immune reactions will not occur. These findings help to explain the widely divergent results of tetanus therapy by means of i.th. injection of tetanus antitoxin. Recommendations for future therapy measures are derived from the findings. (orig./MG)

  9. Influence of acetylcholine on binding of 4-[{sup 125}i]iododexetimide to muscarinic brain receptors

    Energy Technology Data Exchange (ETDEWEB)

    Weckesser, Matthias E-mail: m.weckesser@fz-juelich.de; Fixmann, Anton; Holschbach, Marcus; Mueller-Gaertner, Hans-W

    1998-11-01

    The distribution of nicotinic and muscarinic cholinergic receptors in the human brain in vivo has been successfully characterized using radiolabeled tracers and emission tomography. The effect of acetylcholine release into the synaptic cleft on receptor binding of these tracers has not yet been investigated. The present study examined the influence of acetylcholine on binding of 4-[{sup 125}I]iododexetimide to muscarinic cholinergic receptors of porcine brain synaptosomes in vitro. 4-Iododexetimide is a subtype-unspecific muscarinic receptor antagonist with high affinity. Acetylcholine competed with 4-[{sup 125}I]iododexetimide in a dose-dependent manner. A concentration of 500 {mu}M acetylcholine inhibited 50% of total specific 4-[{sup 125}I]iododexetimide binding to synaptosomes when both substances were given simultaneously. An 800 {mu}M acetylcholine solution reduced total specific 4-[{sup 125}I]iododexetimide binding by about 35%, when acetylcholine was given 60 min after incubation of synaptosomes with 4-[{sup 125}I]iododexetimide. Variations in the synaptic acetylcholine concentration might influence muscarinic cholinergic receptor imaging in vivo using 4-[{sup 123}I]iododexetimide. Conversely, 4-[{sup 123}I]iododexetimide might be an appropriate molecule to investigate alterations of acetylcholine release into the synaptic cleft in vivo using single photon emission computed tomography.

  10. Study on apoptosis of prostate cancer cell induced by 125I seed irradiation

    International Nuclear Information System (INIS)

    Objective: To explore the mechanism of apoptosis induced by 125I seed irradiation on PC3 cells. Methods: Human prostate cancer cell line PC3 was treated by irradiation of 125I (2.77 cGy/h) with various dose. Agarose gel electrophoresis of DNA and flows cytometry were used to detect the apoptosis of PC3 cells and indirect immunofluorescence assay was used to detect the expression of Bcl-2. The activity of Caspase-3 was measured by Caspase Colorimetric Assay Kits. Results: Apoptosis of PC3 cells could be efficiently induced by 125I seed irradiation. The apoptotic peaks were found by flow cytometry and DNA ladder appeared on 1.8% agarose gel. The activity of Caspase-3 on PC3 cells treated by 125I seed irradiation was not changed significantly. Bcl-2 gene expression was down-regulated with the sample concentration increased. Conclusion: 125I irradiation can induce the apoptosis of PC3 cells and the mechanism of apoptosis is related with down regulation of Bcl-2 gene expression and is not related with Caspase-3 activity. (authors)

  11. Preimplant factors affecting postimplant CT-determined prostate volume and the CT/TRUS volume ratio after transperineal interstitial prostate brachytherapy with 125I free seeds

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    Asakura Hirotaka

    2010-09-01

    Full Text Available Abstract Background The aim was to identify preimplant factors affecting postimplant prostate volume and the increase in prostate volume after transperineal interstitial prostate brachytherapy with 125I free seeds. Methods We reviewed the records of 180 patients who underwent prostate brachytherapy with 125I free seeds for clinical T1/T2 prostate cancer. Eighty-one (45% of the 180 patients underwent neoadjuvant hormonal therapy. No patient received supplemental external beam radiotherapy. Postimplant computed tomography was undertaken, and postimplant dosimetric analysis was performed. Univariate and multivariate analyses were performed to identify preimplant factors affecting postimplant prostate volume by computed tomography and the increase in prostate volume after implantation. Results Preimplant prostate volume by transrectal ultrasound, serum prostate-specific antigen, number of needles, and number of seeds implanted were significantly correlated with postimplant prostate volume by computed tomography. The increase in prostate volume after implantation was significantly higher in patients with neoadjuvant hormonal therapy than in those without. Preimplant prostate volume by transrectal ultrasound, number of needles, and number of seeds implanted were significantly correlated with the increase in prostate volume after implantation. Stepwise multiple linear regression analysis showed that preimplant prostate volume by transrectal ultrasound and neoadjuvant hormonal therapy were significant independent factors affecting both postimplant prostate volume by computed tomography and the increase in prostate volume after implantation. Conclusions The results of the present study show that preimplant prostate volume by transrectal ultrasound and neoadjuvant hormonal therapy are significant preimplant factors affecting both postimplant prostate volume by computed tomography and the increase in prostate volume after implantation.

  12. Preparation of 125I-protein A usable for up to 10 months in immunoassays

    International Nuclear Information System (INIS)

    Chloramine-T iodination of protein A from Staphylococcus aureus and gel electrophoretic purification of the iodination mixture results in a stable tracer of high specific and functional activity. Following repeated gel electrophoresis of the tracer only a single component was observed. The specific activity of the 125I-protein A was between 30 and 55 ?Ci/?g. The binding of 125I-protein A to rabbit immunoglobulin exceeded 90% and the tracer competed effectively with unlabelled protein A in binding to cells incubated with sera containing surface antibodies. Storage of the tracer for up to 46 weeks resulted in a moderate decrease in maximal binding to immunoglobulin (from 91% to 64%), in TCA precipitable radioactivity (from 97% to 80%) and an approx. 30% decrease in the ability to detect cell bound immunoglobulin. It is concluded that gel electrophoretic purification of 125I-protein A produces a tracer with a very long shelf life. (Auth.)

  13. Two-dimensional dose distribution around a commercial 125I seed

    International Nuclear Information System (INIS)

    The Monte Carlo method was used to investigate the dose distribution around a 3M Company model 6711 125I seed immersed in a water phantom. Dose rate per unit activity data are presented as a matrix of 63 points surrounding the seed. Relative dose data are presented graphically for two mutually perpendicular directions and compared with the corresponding data for the only other 125I seed currently available, the 3M Company model 6702 125I seed. The 6711 relative dose distribution decreases more rapidly with distance from the seed than does the 6702 relative dose distribution. Uncertainties in the 6711 seed dose distribution produced by end-weld thickness variations were investigated and found to be substantial at certain points

  14. Analysis of 125I-[Tyr3] octreotide receptors of NCI-H466 cell line

    International Nuclear Information System (INIS)

    Objective: To study the affinity of small cell lung carcinoma to [Tyr3] octreotide (TOC). Methods: Taking 125I-[Tyr3] octreotide (labeled by chloramine-T method), as the ligand, small cell lung carcinoma NCI-H466 cell line was inspected for the receptor-binding points and affinity constant. Results: The radio-chemical purity of 125I-TOC purified through sephadex G-10 was higher than 95%. Receptor analysis study showed that the expression of somatostatin receptors on NCI-H446 cells was numerous (Bmax = 1.17 x 105/cell) with strong affinity to 125I-TOC (Kd = 0.56 nM). Conclusion: Labeled TOC could be used for small cell lung carcinoma receptor imaging and radio-pharmaceutical therapy

  15. Dose to the basal layer of the skin from 125I skin contamination

    International Nuclear Information System (INIS)

    The dose rate to the basal layer of the skin from 125I contamination can be significantly underestimated if the contamination is assumed to remain on the skin, and not penetrate into the skin. The dose to basal cells has been calculated for two assumed distributions of 125I with depth in skin and for four basal cell layer depths between 40 and 300 ?m. These results give a maximum cell basal cell dose when the 125I penetration is about twice the basal cell layer depth. This dose may be the limiting dose (as opposed to thyroid dose) in situations where skin contamination can occur. A limit on skin contamination that will ensure the basal cell dose will not exceed 500 mSv.y-1 is recommended. (author)

  16. Radiolabelling and assay of Chinese agkistrodon acutus venom with carrier-free Na 125I

    International Nuclear Information System (INIS)

    Chinese agkistrodon acutus venom (CAAV) was radiolabelled with carrier-free Na125I by the method of Iodogen. The specific activity and radiochemical purity for radiolabelled products were 4236.5 x 1010 Bq/mmol and 98%, respectively. Each CAAV molecule carried 0.52 125I atom. Physical and chemical characterization of radiolabelled CAAV was similar to unradiolabelled CAAV. Binding analysis showed that 125I-CAAV was bound to platelet in a saturable manner. Binding sites per platelet were 13255 +-6292/platelet. The dissociation constant (Kd) was 3.2 +- 0.69 x 10-10 mol/L. These results are similar to binding sites of other snake venom on platelet. The investigation showed that radiolabelled CAAV made by our laboratory was useful for radioligand binding assay

  17. Preparation and Evaluation of (125I) Daunorubicin as a Potential Agent for Tumor Detection and radiotherapy

    International Nuclear Information System (INIS)

    In this study, the optimization of daunorubicin labeling with iodine-125 and its biological evaluation were described. Daunorubicin was labeled via direct electrophilic substitution using chloramine-T as oxidizing agent. The optimum amounts of reactants were: 40?g daunorubicin, 30?g Chloramine-T and ? 19 KBq carrier free Na125I. The labeled daunorubicin was stable for more than 24 hours. Results of the in-vivo evaluation revealed that the tracer, [125I] daunorubicin, tends to localize in tissues with high proliferation rate with preferential accumulation in cancerous tissues. Imaging should be carried at 3 hours post injection. The in-vitro cell growth inhibition assay showed that the effect of [125I] Daunorubicin was stronger than the effect of cold daunorubicin which strongly suggested that its cytotoxicity was mainly due to radiotoxicity rather than chemotherapeutic activity.

  18. Preparation and purification of 125I-labelled PEGylated thymosin ?1

    International Nuclear Information System (INIS)

    Objective: To prepare a highly purified 125I-PEGylated thymosin ?1 (PEG-TA1) with satisfied bioactivity for using in the distribution and excretion study in animals. Methods: Tyr-PEG-TA1 was iodinated by means of Iodogen method. The ZipTip pipette tips were utilized to monitor the reaction process for the optimization of reaction conditions. A two-step gel filtration chromatography with Sephadex G50 followed by Sephadex G10 was applied to purify the labelled products. The bioactivity assay of PEG-TA1, Tyr-PEG-TA1 and 125I-Tyr-PEG-TA1 were performed by an enzyme immunoassay (EIA) method. Results: The optimum condition of labelling reaction was: shaking for 20 min at 25 degree C in 0.1 mol/L phosphate buffer (0.1 mol/L NaCl) with the pH value of 7.0. Slight but no significant difference of bioactivity among the PEG-TA1, Tyr-PEG-TA1 and the 125I-Tyr-PEG-TA1 was observed. After the two-step purification process, a product of 125I-Tyr-PEG-TA1 with radiochemical purity of 95% and specific activity of 39.4 Bq/ng was obtained. Conclusion: A successful preparation of 125I-Tyr-PEG-TA1 was achieved, and the radiochemical purity and the specific activity of the 125I labeled molecules satisfied the requirements of non-clinical pharmacokinetic study. (authors)

  19. Simple detection of hepatitis C virus using 125I-2'-deoxyuridine triphosphate and gamma counter

    International Nuclear Information System (INIS)

    Hepatitis C Virus (HCV) is the major cause of post transfusion and sporadic non A, non B hepatitis. Current infection of HCV can be detected by PCR method. Using PCR, it has been possible to detect HCV viremia prior to immunological sero-conversion and to detect fluctuation of viremia in antibody-positive chronic HCV patients undergoing therapy with interferon. In this study, we established the simple method to detect HCV DNA by incorporation of 125I-deoxyuridine triphosphate(dUTP) into DNA during the PCR, and counted the radioactivity of PCR product by gamma counter. 125I-2'-deoxyuridine 5'-triphosphate was prepared, and incorporated into DNA during PCR. dUTP was radiolabeled by the iododemercuration of 5-mercuri intermediate. Iododemercuration labeling was completed with 98% yield and the obtained product was incorporated into DNA without further purification. After incorporation, covalently bonded radioiodine substituent was remained stable during PCR procedure HCV positive standard and positive patient sera in immunological assay were centrifuged. HCV RNA is isolated from by GTC(Guanidine Thiocyanate) and phenol/chloroform extraction method and synthesized complementary DNA by using reverse transcriptase. The '125I-dUTP was incorporated into HCV C DNA during PCR. PCR product purified by fiber matrix column and counted by gamma counter. PCR products were electrophoresized, and autoradiography image obtained. Amplified HCV DNA by 125I-dUTP PCR obtained the band on the gel by electrophoresis and autoradiography at the same position. In patient sera, radioactivity of HCV positive sample was 8 times higher than HCV negative viremia sample. We established HCV detection method using 125I-dUTP. 125I-dUTP PCR detection of HCV is convenient and reporducible

  20. Comparison of carcinogenicity of 131I and 125I in tyroid gland of the rat

    International Nuclear Information System (INIS)

    To determine whether there was a difference in the carcinogenicity of 131I and 125I for the thyroid gland, groups of 40 rats on a low-iodine diet were injected with various doses of one of the nuclides. The doses of 131I injected were 125, 50, 20, 8 and 3.2 ?Ci; doses of 125I were four times higher. The surviving rats were killed two years after injection and autopsies with complete histopathological examinations were performed. The results of survival and thyroid function studies revealed that the dose ranges in ?Ci for the two nuclides could not be directly compared and that each dose of 125I could best be compared with a 10- to 25-fold lower dose of 131I. The morphological findings in the follicular epithelium of the thyroid gland showed that the peak of induction of hyperplasia, cysts and tumours by 125I occurred in the group injected with 80 ?Ci, whereas comparable changes after 131I administration were observed in the group injected with the lowest dose (3.2 ?Ci). The peak of tumour induction by 125I in the parafollicular epithelium was found in the group injected with 32 ?Ci; the peak with 131I was probably missed, since the comparable dose for this nuclide was below the range of doses injected. The highest incidence of tumours of these parafollicular cells was 2.5 times the spontaneous incidence in control rats. However, extrapolation of these results to man seems unreliable, since the spontaneous incidence of tumours of the parafollicular cells is much higher in rats than in man. It may be concluded that 125I does not induce more tumours of the follicular cells than does 131I as has been suggested by others. (author)

  1. An instrument for measurement of 125I with automatic efficiency correction

    International Nuclear Information System (INIS)

    Counting efficiencies for 125I are often uncertain because of self-absorption of the low-energy radiation. A special purpose instrument, AEP-5285, has been designed to simplify the measurement of 125I activities using a known technique in which the observed counting rate is compensated for self-absorption and any other uncertainties in the counting efficiency by making use of the coicidence properties of the radiation. The instrument contains pulse amplifiers, discriminators to define the energy regions of interest, and operational amplifier circuits to perform the necessary calculations automatically, and it displays an estimate of the source activity in becquerels. (auth)

  2. Selective binding of 2-[{sup 125}I]iodo-nisoxetine to norepinephrine transporters in the brain

    Energy Technology Data Exchange (ETDEWEB)

    Kung, M.-P.; Choi, Seok-Rye; Hou, Catherine; Zhuang, Z.-P.; Foulon, Catherine; Kung, Hank F. E-mail: kunghf@sunmac.spect.upenn.edu

    2004-07-01

    A radioiodinated ligand, (R)-N-methyl-(2-[{sup 125}I]iodo-phenoxy)-3-phenylpropylamine, [{sup 125}I]2-INXT, targeting norepinephrine transporters (NET), was successfully prepared. A no-carrier-added product, [{sup 125}I]2-INXT, displayed a saturable binding with a high affinity (K{sub d}=0.06 nM) in the homogenates prepared from rat cortical tissues as well as from LLC-PK{sub 1} cells expressing NET. A relatively low number of binding sties (B{sub max}=55 fmol/mg protein) measured with [{sup 125}I]2-INXT in rat cortical homogenates is consistent with the value reported for a known NET ligand, [{sup 3}H]nisoxetine. Competition studies with various compounds on [{sup 125}I]2-INXT binding clearly confirmed the pharmacological specificity and selectivity for NET binding sites. Following a tail-vein injection of [{sup 125}I]2-INXT in rats, a good initial brain uptake was observed (0.56% dose at 2 min) followed by a slow washout from the brain (0.2% remained at 3 hours post-injection). The hypothalamus (a NET-rich region) to striatum (a region devoid of NET) ratio was 1.5 at 3 hours post-i.v. injection. Pretreatment of rats with nisoxetine significantly inhibited the uptake of [{sup 125}I]2-INXT (70-100% inhibition) in locus coeruleus, hypothalamus and raphe nuclei, regions known to have a high density of NET; whereas escitalopram, a serotonin transporter ligand, did not show a similar effect. Ex vivo autoradiography of rat brain sections of [{sup 125}I]2-INXT (at 3 hours after an i.v. injection) displayed an excellent regional brain localization pattern corroborated to the specific NET distribution in the brain. The specific brain localization was significantly reduced by a dose of nisoxetine pretreatment. Taken together, the data suggest that [{sup 123}I]2-INXT may be useful for mapping NET binding sites in the brain.

  3. Investigation of properties of KG4?125I and NNQ601 chambers

    International Nuclear Information System (INIS)

    Experience has been stated in the paper gained during exploitation of ionization chambers KG4?125I of Poli sh fabrication and of chambers NNQ of Czechoslovakian fabrication. Special attention has been paid to determination of energy sensitivity to the energy range near to 30 keV. In the NNQ instrument there is it's own digitel system for estimation. Dynamic electrometer TAKEDA-RIKEN 840M (Japan) is used in the KG4?125 I chamber. Specifications are compared of both types of chambers and their fitness fo measurement of come nuclides

  4. Differences in the hepatic metabolism of 99mTc and 125I labelled galactosyl neoglycoalbumin

    International Nuclear Information System (INIS)

    Galactosyl neoglycoalbumin (NGA) is a synthetic ligand for the asialoglycoprotein receptor (hepatic binding protein) which resides exclusively on hepatocytes. Uptake of 99mTc allows assessment of liver function based on receptor concentration as well as dynamic liver imaging. However, most biochemical studies on the uptake and hepatic mechanism of asiaglycoproteins have used 125I labelled ligands. The authors have undertaken, therefore, a comparative study of NGA uptake and hepatic metabolism in the isolated perfused rat liver using both 99mTc and 125I radiolabelled NGA

  5. Protection of 125I-glucagon from damage during the purification procedure in presence of gelatine

    International Nuclear Information System (INIS)

    To produce a suitable radioiodinated glucagon for radioimmunoassay, the influence of various kinds of albumins and gelatine on the stability of iodoglucagon during the purification procedure was studied. The destruction of 125I-glucagon during the purification in presence of commercial albumin could not be prevented either after Trasylol treating, whereas gelatine did not cause any damage of 125I-glucagon which had the immunoreactivity suitable for radioiummunoassay. The sensitivity for RIA calculated as the standard deviation derived values of radioactivity corresponding to zero concentration of hormone was +-12 pg per ml. (T.I.)

  6. Optimization of the synthesis of a high specific activity 125 I-labelled hapten for radioimmunoassays

    International Nuclear Information System (INIS)

    In this first report it is described the synthesis, separation and purification of the 2-radioiodinated histamine ''125 I-labelled histamine by a mixed anhydride reaction. About 75% incorporation of I''1125, from Na''125, I, was achieved with a molecular ratio of 1:1 mixed anhydride:histamine. The radiochemical purity of the conjugate by TLC was >99% and its theoretical specific activity, 3850 mu Ci/mug. Dissolved in ethanol and held at -20 degree centigree under darkness decomposition on storage did not exceed 1% per month

  7. CT-guided 125I brachytherapy for mediastinal metastatic lymph nodes recurrence from esophageal carcinoma: Effectiveness and safety in 16 patients

    International Nuclear Information System (INIS)

    Objectives: To retrospectively evaluate effectiveness and safety of CT-guided 125I brachytherapy in 16 patients with mediastinal metastatic lymph nodes recurrence from esophageal carcinoma. Materials and methods: Sixteen metastatic lymph nodes in 16 patients were percutaneously treated in 19 125I brachytherapy sessions. Each metastatic lymph node was treated with computed tomographic (CT) guidance. Follow-up contrast material-enhanced CT or positron emission tomographic (PET) scans were reviewed and the treatment's effectiveness was evaluated. Results: Months are counted from the first time of 125I brachytherapy and the median duration of follow-up was 11 months (range, 5–16 months). The local control rates after 3, 6, 10 and 15 months were 75.0, 50.0, 42.9 and 33.3% respectively. At the time of writing, four patients are alive without evidence of recurrence at 16, 9, 16 and 9 months. The 4 patients presented good control of local tumor and no systemic recurrence, and survived throughout the follow-up period. The other 12 patients died of multiple hematogenous metastases 5–15 months after brachytherapy. A small amount of local hematoma occurred in 2 patients that involved applicator insertion through the lung. Two patients presented pneumothorax with pulmonary compression of 30 and 40% after the procedure and recovered after drainage. One patient had minor displacement of radioactive seeds. Severe complications such as massive bleeding and radiation pneumonitis did not occur. Conclusion: 125I radioactive seed implantation is effective and may be safely applied to mediastinal metastatic lymph nodes recurrence from esophageal carcinoma

  8. CT-guided {sup 125}I brachytherapy for mediastinal metastatic lymph nodes recurrence from esophageal carcinoma: Effectiveness and safety in 16 patients

    Energy Technology Data Exchange (ETDEWEB)

    Gao, Fei, E-mail: gaof@sysucc.org.cn [State Key Laboratory of Oncology in South China, Guangzhou 510060 (China); Department of Interventional Radiology, Sun Yat-sen University Cancer Center, 651 Dongfeng Road East, Guangzhou 510060 (China); Li, Chuanxing, E-mail: licx@sysucc.org.cn [State Key Laboratory of Oncology in South China, Guangzhou 510060 (China); Department of Interventional Radiology, Sun Yat-sen University Cancer Center, 651 Dongfeng Road East, Guangzhou 510060 (China); Gu, Yangkui, E-mail: guyk@sysucc.org.cn [State Key Laboratory of Oncology in South China, Guangzhou 510060 (China); Department of Interventional Radiology, Sun Yat-sen University Cancer Center, 651 Dongfeng Road East, Guangzhou 510060 (China); Huang, Jinhua, E-mail: huangjh@sysucc.org.cn [State Key Laboratory of Oncology in South China, Guangzhou 510060 (China); Department of Interventional Radiology, Sun Yat-sen University Cancer Center, 651 Dongfeng Road East, Guangzhou 510060 (China); Wu, Peihong, E-mail: vivian-link@163.com [State Key Laboratory of Oncology in South China, Guangzhou 510060 (China); Department of Interventional Radiology, Sun Yat-sen University Cancer Center, 651 Dongfeng Road East, Guangzhou 510060 (China)

    2013-02-15

    Objectives: To retrospectively evaluate effectiveness and safety of CT-guided {sup 125}I brachytherapy in 16 patients with mediastinal metastatic lymph nodes recurrence from esophageal carcinoma. Materials and methods: Sixteen metastatic lymph nodes in 16 patients were percutaneously treated in 19 {sup 125}I brachytherapy sessions. Each metastatic lymph node was treated with computed tomographic (CT) guidance. Follow-up contrast material-enhanced CT or positron emission tomographic (PET) scans were reviewed and the treatment's effectiveness was evaluated. Results: Months are counted from the first time of {sup 125}I brachytherapy and the median duration of follow-up was 11 months (range, 5–16 months). The local control rates after 3, 6, 10 and 15 months were 75.0, 50.0, 42.9 and 33.3% respectively. At the time of writing, four patients are alive without evidence of recurrence at 16, 9, 16 and 9 months. The 4 patients presented good control of local tumor and no systemic recurrence, and survived throughout the follow-up period. The other 12 patients died of multiple hematogenous metastases 5–15 months after brachytherapy. A small amount of local hematoma occurred in 2 patients that involved applicator insertion through the lung. Two patients presented pneumothorax with pulmonary compression of 30 and 40% after the procedure and recovered after drainage. One patient had minor displacement of radioactive seeds. Severe complications such as massive bleeding and radiation pneumonitis did not occur. Conclusion: {sup 125}I radioactive seed implantation is effective and may be safely applied to mediastinal metastatic lymph nodes recurrence from esophageal carcinoma.

  9. Development of esophageal 125I seed irradiated stent and its experiment

    International Nuclear Information System (INIS)

    Objective: To investigate the feasibility of developing the esophageal irradiating esophageal stent by placing 125I seed into it, the safety of the irradiative stent esophageal in animal experiments. Methods: (1) Development of esophageal 125I seed irradiated stent: a plastic 'bullet chamber' was moulded which held only one 125I seed. Its distribution and the spot where it was stitched on outside the stents. Thus esophageal intraluminal irradiating stents were developed. (2) Animal experiment: 36 rabbits were randomly assigned to 4 groups according to different irradiated dosage, 9 rabbits in each group. Intraluminal irradiated stents each with two 125I seeds totaling 22.2 MBq (group A), 44.4 MBq (group B) and 66.6 MBq (group C) respectively were placed in the rabbits esophagus and stents without 125I seeds were placed in group D rabbits esophagus which as control group. Three rabbits of each group were killed at the 2th, 4th, or 8th week after insertion of the stents, followed by esophageal contrast exam and CT scan to observe displacement of stents and transposition of 125I seed. The damage and its degree of esophagus and the lung, bronchus and large vessels around it caused by intraluminal irradiated stents were observed macroscopically or under optical and electric microscope. Results: (1) Development of esophageal intraluminal irradiated stents: 125I seed could be stitched on outside the stents firmly. Experiments of filling and releasing seeds in vitro were feasible. Irradiated steats could be easily placed in rabbits esophagus. It was safe for no losing of radioactive source has been found after they have been placed in esophagus for a long-term. (2) Animal experiments: the esophageal wall near 125I seed thickened most distinctly in mental groups during the 8th week[ group A(4.2 ± 0.3)mm,group B(4.3 ± 0.3)mm, group C(4.5 ± 0.3)mm]. There was a significant difference between the experimental group and control group [(3.1 ± 0.1) mm (P0.05). Four weeks after the produce, no other noticeable changes of thickness occurred among the 4 groups except esophageal bore size narrowed progressively along with time, there was no significant difference between the esophageal bore size of experimental groups during the 8th [group A (5.7 ± 0.2) mm, group B (5.6 ± 0.3) mm, group C (5.6 ± 0.3) mm ] and control group (5.6 ± 0.2) mm (P>0.05). The macroscopical observation of lung, trachea and thoracic aortal wall around the stents were consistent with those under optical microscope, however the ultrastructure had mild impairment observed under electric microscope. Conclusion: The design and fabrication of binding esophageal intraluminal irradiated stents have been proven to be feasible. The radioactivity of 125I radioactive seeds commonly used in clinics only causes slight injury to the lung, trachea, large vessels around esophagus in animal experiment, 125I radioactive seed has no obvious effect of inhibition or stimulation on the hyperplastic esophageal mucosa due to the placement of stent. It is possible that 125I radioactive seeds placed in vivo for a long time stimulate esophageal smooth muscle to proliferate. (authors)

  10. Improved radial dose function estimation using current version MCNP Monte-Carlo simulation: Model 6711 and ISC3500 125I brachytherapy sources

    International Nuclear Information System (INIS)

    Improved cross-sections in a new version of the Monte-Carlo N-particle (MCNP) code may eliminate discrepancies between radial dose functions (as defined by American Association of Physicists in Medicine Task Group 43) derived from Monte-Carlo simulations of low-energy photon-emitting brachytherapy sources and those from measurements on the same sources with thermoluminescent dosimeters. This is demonstrated for two 125I brachytherapy seed models, the Implant Sciences Model ISC3500 (I-Plant) and the Amersham Health Model 6711, by simulating their radial dose functions with two versions of MCNP, 4c2 and 5

  11. The effectiveness of 125I seed interstitial brachytherapy for transplantation tumor of human pancreatic carcinoma in nude mice: an experiment in vivo

    International Nuclear Information System (INIS)

    Objective: To discuss the effectiveness and therapeutic mechanism of 125I interstitial brachytherapy for transplantation tumor of human pancreatic carcinoma in nude mice. Methods: The human pancreatic cell line Sw1990 was subcutaneously injected into the right lower limb partially dorsal area next to the groin of the immunodeficient BABL /c nude mice. The tumor was removed and cut into small pieces after it was formed,then the tumor pieces were inoculated in nude mice. The tumor developed to 8-10 mm in size after six weeks. A total of 16 nude mice with the suitable tumor size were used in this study. The 16 experimental mice were randomly and equally divided into two groups. The mice in study group (n = 8) were implanted with 125I seeds, while the mice in control group (n = 8) were implanted with ghost seeds. After the implantation both the long and short diameter of the tumors as well as the mouse body weight were measured every 4 days. The tumor weight was measured when the mouse was sacrificed. The paraffin-embedded samples were sent for histopathological examination. Apoptotic cells were checked with terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) method. Expression of proliferating cell nuclear antigen (PCNA) was detected with immuno-histochemical staining. Results: The tumor grew slowly in the study group, but rapidly in the control group. The tumor weight in the study group and the control group was (2.68 ± 0.70)g and (4.68 ± 1.45)g, respectively, the difference between two groups was statistically significant (P = 0.021). The tumor inhibition rate was about 42.66%. No significant difference in body weight of nude mice existed between two groups both before and after the treatment (P > 0.05). Marked tumor necrosis was seen in study group, but no obvious, or only a little, tumor necrosis could be observed in the control group. The apoptotic index checked with the TUENL method in the study group and control group was (23.2 ± 1.9)% and (8.1 ± 1.5)%, respectively, and the difference between two groups was statistically significant (P 125I interstitial brachytherapy is an effective treatment for transplantation tumor of human pancreatic carcinoma in nude mice. Its mechanisms include directly killing the tumor cells, inducing tumor cell apoptosis and reducing cell proliferation. Additionally, 125I seeds implantation in vivo tumor is safe for the surrounding organs. (authors)

  12. Impact of target volume coverage with Radiation Therapy Oncology Group (RTOG) 98-05 guidelines for transrectal ultrasound guided permanent Iodine-125 prostate implants

    International Nuclear Information System (INIS)

    Purpose: Despite the wide use of permanent prostate implants for the treatment of early stage prostate cancer, there is no consensus for optimal pre-implant planning guidelines that results in maximal post-implant target coverage. The purpose of this study was to compare post-implant target volume coverage and dosimetry between patients treated before and after Radiation Therapy Oncology Group (RTOG) 98-05 guidelines were adopted using several dosimetric endpoints. Materials and methods: Ten consecutively treated patients before the adoption of the RTOG 98-05 planning guidelines were compared with ten consecutively treated patients after implementation of the guidelines. Pre-implant planning for patients treated pre-RTOG was based on the clinical target volume (CTV) defined by the pre-implant TRUS definition of the prostate. The CTV was expanded in each dimension according to RTOG 98-05 and defined as the planning target volume. The evaluation target volume was defined as the post-implant computed tomography definition of the prostate based on RTOG 98-05 protocol recommendations. Implant quality indicators included V100, V90, V100, and Coverage Index (CI). Results: The pre-RTOG median V100, V90, D90, and CI values were 82.8, 88.9%, 126.5 Gy, and 17.1, respectively. The median post-RTOG V100, V90, D90, and CI values were 96.0, 97.8%, 169.2 Gy, and 4.0, respectively. These differences were all statistically significant. Conclusions: Implementation of the RTOG 98-05 implant planning guidelines has increased coverage of the prostate by the prescription isodose lines compared with our previous technique, as indicated by post-implant dosimetry indices such as V100, V90, D90. The CI was also improved significantly with the protocol guidelines. Our data confirms the validity of the RTOG 98-05 implant guidelines for pre-implant planning as it relates to enlargement of the CTV to ensure adequate margin between the CTV and the prescription isodose lines

  13. Synthesis of 4-[2-(4-azidophenyl)-5-(3-iodo-125I-phenyl)-1H-imidazol-4-yl]py ridine (SB 20678-[125I]), a pyridinyl imidazole cytokine inhibitor

    International Nuclear Information System (INIS)

    The pyridinyl imidazole cytokine-suppressing anti-inflammatory drug (CSAID), SB 206718 (1) was required in 125I-labeled form for photoaffinity ligand studies. The target compound (SB 206718-[125I], [125I)1) was obtained via conversion of the highly functionalized 1 to a tributylstannyl derivative. Radioiododestannylation using Na125I in the presence of chloramine-T gave good radiochemical yields of the title compound (42-69%, four radiosyntheses) at high radiochemical purity (> 98%) after HPLC purification at specific activities of 1670-1736 Ci/mmol. (author)

  14. Validation of 125I-hCG as a marker for elimination of hCG and stability of 125I-hCG after in vivo injection in humans

    DEFF Research Database (Denmark)

    Christensen, T B; Marqversen, J; Engbaek, F; Berger, P; Bacher, T; von der Maase, H

    1999-01-01

    We have recently introduced 125I-hCG as an elimination marker in patients with human chorionic gonadotrophin (hCG) producing testicular cancer. 125I-hCG is a well-known reagent in clinical biochemistry and is used extensively in hCG assays. Previous studies have shown that the iodination process leaves the hCG molecule mainly intact. The iodination, purification and stability of 125I-hCG tracer are described. The aim of the present study was to determine whether or not 125I is associated with hC...

  15. Comparison of cyclosporine determinations in whole blood by three different methods. HPLC, 125I RIA and 3H RIA

    International Nuclear Information System (INIS)

    The authors have analyzed and compared the cyclosporine concentrations in whole blood specimens from pediatric renal transplant patients using three different methods: high-performance liquid chromatography (HPLC) (5u C18 reverse-phase column), 3H radioimmunoassay (RIA), and 125I RIA (substituted 3H-tracer in Sandoz Kit with 125I tracer. Results obtained by the 125I RIA correlated well with results obtained by the 3H RIA. Both RIA methods had similar correlation with the HPLC method. The 125I RIA method showed higher sensitivity and greater precision than the 3H RIA method. The authors conclude that the 125I RIA method can be used for cyclosporine determination in whole blood specimens. The use of the 125I RIA provides a simple and rapid method with higher counting efficiency and less background quenching than the 3H RIA method, which requires cumbersome liquid scintillation counting procedures

  16. Development of a high specific activity radioligand, 125I-LSD, and its application to the study of serotonin receptors

    International Nuclear Information System (INIS)

    125I-Labeled receptor ligands can be synthesized with specific activities exceeding 2000 Ci/mmol, making them nearly 70-fold more sensitive in receptor site assays than (mono) tritiated ligands. We have synthesized and characterized 125I-lysergic acid diethylamide (125I-LSD), the first radioiodinated ligand for serotonin receptor studies. The introduction of 125I at the 2 position of LSD increased both the affinity and selectivity of this compound for serotonin 5-HT2 receptors in rat cortex. The high specific activity of 125I-LSD and its high ratio of specific to nonspecific binding make this ligand especially useful for autoradiographic studies of serotonin receptor distribution. We have found that 125I-LSD binds with high affinity to a class of serotonin receptors in the CNS of the marine mollusk Aplysia californica

  17. Determination of bone density via /sup 125/I-densitometry in idiophathic scoliosis

    Energy Technology Data Exchange (ETDEWEB)

    Matzen, K.A.; Milachowski, K.A.; Weinberger, N.; Rohloff, R.

    1984-12-01

    The aim of the present study was to find out whether idiopathic scoliosis is associated with a general reduction of the calcium salt content of the bones. The study was conducted in a scoliosis patient group of 48 individuals, using /sup 125/I densitometry.

  18. Determination of bone density via 125I-densitometry in idiophathic scoliosis

    International Nuclear Information System (INIS)

    The aim of the present study was to find out whether idiopathic scoliosis is associated with a general reduction of the calcium salt content of the bones. The study was conducted in a scoliosis patient group of 48 individuals, using 125I densitometry. (orig.)

  19. Use of immunoaffinity chromatography for purification of 125I-labeled human prolactin

    International Nuclear Information System (INIS)

    Researchers assessed a simple method for purifying 125I-labeled human prolactin, taking advantage of the abundant supplies of monoclonal antibodies available. 125I-labeled human prolactin purified by immunoaffinity chromatography is compared with that purified by gel filtration on Sephadex G-100. Researchers used monoclonal antibodies to prolactin to prepare the affinity chromatography columns. Prolactin was radiolabeled by the Chloramine T method, purified by each of the above procedures, and the binding and displacement characteristics were studied in radioimmunoassays in which either monoclonal antibodies or a rabbit anti-prolactin serum was the first antibody. A nonimmune fraction of 125I-labeled prolactin that co-eluted with the immunoreactive hormone from Sephadex G-100 was removed by affinity chromatography, which increased the antibody binding of 125I-labeled prolactin in the radioimmunoassay in the absence of unlabeled antigen (B/T0, in percent) twofold or more, increased the assay sensitivity, and increased the slope of antigen displacement measured by the 50% intercept. Several advantages make this the purification method of choice

  20. Use of immunoaffinity chromatography for purification of /sup 125/I-labeled human prolactin

    Energy Technology Data Exchange (ETDEWEB)

    Stuart, M.C.; Boscato, L.M.; Underwood, P.A.

    1983-02-01

    Researchers assessed a simple method for purifying /sup 125/I-labeled human prolactin, taking advantage of the abundant supplies of monoclonal antibodies available. /sup 125/I-labeled human prolactin purified by immunoaffinity chromatography is compared with that purified by gel filtration on Sephadex G-100. Researchers used monoclonal antibodies to prolactin to prepare the affinity chromatography columns. Prolactin was radiolabeled by the Chloramine T method, purified by each of the above procedures, and the binding and displacement characteristics were studied in radioimmunoassays in which either monoclonal antibodies or a rabbit anti-prolactin serum was the first antibody. A nonimmune fraction of /sup 125/I-labeled prolactin that co-eluted with the immunoreactive hormone from Sephadex G-100 was removed by affinity chromatography, which increased the antibody binding of /sup 125/I-labeled prolactin in the radioimmunoassay in the absence of unlabeled antigen (B/T0, in percent) twofold or more, increased the assay sensitivity, and increased the slope of antigen displacement measured by the 50% intercept. Several advantages make this the purification method of choice.

  1. Use of immunoaffinity chromatography for purification of 125I-labeled human prolactin.

    Science.gov (United States)

    Stuart, M C; Boscato, L M; Underwood, P A

    1983-02-01

    We assessed a simple method for purifying 125I-labeled human prolactin, taking advantage of the abundant supplies of monoclonal antibodies available. 125I-Labeled human prolactin purified by immunoaffinity chromatography is compared with that purified by gel filtration on Sephadex G-100. We used monoclonal antibodies to prolactin to prepare the affinity chromatography columns. Prolactin was radiolabeled by the Chloramine T method, purified by each of the above procedures, and the binding and displacement characteristics were studied in radioimmunoassays in which either monoclonal antibodies or a rabbit anti-prolactin serum was the first antibody. A nonimmune fraction of 125I-labeled prolactin that co-eluted with the immunoreactive hormone from Sephadex G-100 was removed by affinity chromatography, which increased the antibody binding of 125I-labeled prolactin in the radioimmunoassay in the absence of unlabeled antigen (B/T0, in percent) twofold or more, increased the assay sensitivity, and increased the slope of antigen displacement measured by the 50% intercept. Several advantages make this the purification method of choice. PMID:6821925

  2. Stability of 125I label after intragastric or intravenous administration of radioiodinated latexes to mice

    International Nuclear Information System (INIS)

    The stability of 125I tracer bound to styrene-butadiene copolymer latexes was determined by administering the latexes intragastrically or i.v. to mice. Some of the latexes had been given an additional coating of polystyrene after iodination. Latex particle sizes were 0.17 to 0.25 ?m; coatings were 0.01 to 0.02 ?m. 125I found in the urine after latex administration was not bound to latex particles and was used as a measure of deiodination. Styrene: butadiene ratios used for latex preparation and percent of administered radioactivity recovered in the urine one day after intragastric administration were as follows: (a) 95:5 uncoated latex, 32.8%; (b) 84:16 uncoated latex, 56.3%; (c) 84:16 coated latex, 27.0%; (d) 60:40 uncoated latex, 14.0%; (e) 60:40 coated latex, 8.9%. Following i.v. administration of latexes, similar amounts of 125I were excreted in the urine during the first day. The remainder of i.v. administered radioactivity was retained in the liver with only slight loss in 5 days. Because of the instability of the label, radioiodinated latexes could not be used to quantitate latex absorption by the intestine; however, the data indicate that a small fraction (125I loss from radioiodinated styrene-butadiene copolymer latexes is inevitable because of the lability of the C-I chemical bond

  3. Behaviour of 125I added to limnocorrals in two Canadian Shield lakes of differing trophic states

    International Nuclear Information System (INIS)

    The main objectives of our investigation were to determine the loss rate of iodine from water to sediment and to gain a better understanding of the behaviour of iodine in Shield lakes. Iodine-125 and tritium (3HHO) were added to the epilimnion of limnocorrals (enclosures) in mesotrophic Lake 226 and eutrophic Lake 227, Experimental Lakes Area, northwestern Ontario. The change in the 125I/3H ratio was used to measure the loss of 125I from the epilimnion. Loss rate coefficients, (k), ranged from -0.0017 to -0.0074 day-1. The 125I was found primarily in the d) had geometric means (/xgeometric standard deviations) of 2526/x62.1 l·kg-1 dry weight (dw) for suspended sediment, 1362 ± 2.9 l·kg-1 dw for particles in sediment traps and 132/x6 l·kg-1 dw for bottom sediment. Concentrations in fish ranged from = 8 to 184 Bq·g-1 dw, whereas concentration factors from water to fish ranged from 20 to 390 l·kg-1 dw. Iodine behaves as a conservative element in Shield lakes, although it is available for uptake by biota. The persistence of 125I in water and its accumulation by fish emphasizes the potential importance of these pathways in the radiological dose to humans

  4. Preparation of a 125I labeled derivative of penicillin to be used for radioimmunoassay

    International Nuclear Information System (INIS)

    A 125I-BSA Penicilloyl conjugate was prepared by coupling penicillin G to Bovine Serum Albumine previously labeled with iodine-125. The reaction of fixation by covalent binding was made in alkaline solution without the use of carbodiimide. Immunoreactivity and specific activity of this labeled conjugate enable radioimmunoassay of penicilloyl groups

  5. Dosimetry and treatment planning of Occu-Prosta 125I seeds for intraocular lesions

    International Nuclear Information System (INIS)

    Intraocular malignant lesions are frequently encountered in clinical practice. Plaque brachytherapy represents an effective means of treatment for intraocular lesions. Recently Radiopharmaceutical Division, BARC, Mumbai, has indigenously fabricated reasonable-cost 125I sources. Here we are presenting the preliminary experience of dosimetry of sources, configuration of treatment planning system (TPS) and quality assurance (QA) for eye plaque therapy with Occu-Prosta 125I seeds, treated in our hospital, for a patient with ocular lesions. 125I seeds were calibrated using well-type chamber. BrachyVision TPS was configured with Monte Carlo computed radial dose functions and anisotropy functions for 125I sources. Dose calculated by TPS at different points in central axis and off axis was compared with manually calculated dose. Eye plaque was fabricated of 17 karat pure gold, locally. The seeds were arranged in an outer ring near the edge of the plaque and in concentric rings throughout the plaque. The sources were manually digitized on the TPS, and dose distribution was calculated in three dimensions. Measured activity using cross-calibrated well-type chamber was within ± 10% of the activity specified by the supplier. Difference in TPS-calculated dose and manually calculated dose was within 5%. Treatment time calculated by TPS was in concordance with published data for similar plaque arrangement. (author)

  6. Preparation and animal testing of 125-I-IMP as a scintigraphic agent for brain

    International Nuclear Information System (INIS)

    RS-N-isopropyl-p-iodoamphetamine (IMP) is radio-iodinated by isotopic exchange using Cu (I) as catalyst in presence of an excess of Sn (II) as reductor. The metod is simple and fast. A quantitative (99%) labelling yield of 125I-IMP can be obtained within 30 minutes. Free ionic 125I is less than 3%. After ether extraction, radiochemical purity is greater than 98%, free ionic 125I 125I-IMP in Spragne-Dawlay rat, the brain uptake is prompt, with 1.32%/g of the injected dose reaching the brain by 5 min and peak uptake (1.49%/g) at 1h. There is a slight fall in brain activity after 3h. At all times the brain-to-blood ratio is more than 12. After the administration the highest radioactivity ratios of brain/blood, brain/skeletal muscle and brain/bone are 17.5, 5 and 9 at 30-60 min respectively

  7. Synthesis of the 123I- and 125I-labeled cholinergic nerve marker (-)-5-iodobenzovesamicol

    International Nuclear Information System (INIS)

    The highly toxic curaremimetic and cholinergic neuron marker (-)-5-iodobenzovesamicol (IBVM) has been labeled with iodine-125 and iodine-123. [125I]IBVM, suitable for animal distribution and ex vivo autoradiographic studies, was synthesized by solid-state exchanger; isolated yields were 65-89% with specific activities in the range of 130-200 Ci/mmol. The synthesis of no-carrier-added (-)-5-[125I]IBVM from the corresponding chiral (-)-5-(tri-n-butyltin) derivative using Na125I was evaluated using the oxidants H2O2, peracetic acid and chloramine-T. Both peracetic acid and chloramine-T gave good yields (70-95%). However, when Na123I was utilized, acceptable yields of [123I]IBVM were obtained only with chloramine-T. Distribution analyses of [125I]IBVM and [123I]IBVM in mice 4 h following intravenous administration show essentially equivalent concentrations of the two tracers in the four brain regions sampled. The exceptionally high specific activity of [123I]IBVM has made possible the evaluation of this radiotracer in humans. (Author)

  8. Staff dose of hospitalization in the treatment of patients in ophthalmic brachytherapy with 125 I

    International Nuclear Information System (INIS)

    The objective of this work, therefore, has been the evaluation of the dose levels which nursing staff can receive in care for ophthalmic brachytherapy patients treated with 125 I from measurements made on the same, evaluating, in an experimental way, job security following the PR rules laid down for these treatments. (Author)

  9. Preparation of 125I labelled progesterone-11α-hemisuccinate tyrosine methyl esther

    International Nuclear Information System (INIS)

    Progesterone assay in serum samples is best carried out by radioimmunoassay due to its high sensitivity, specificity and simplicity. An essential reagent for the assay is 125I-labelled progesterone. Labeling of progesterone-11α-hemisuccinate-TME is carried out using the lactoperoxidase method by reacting progesteron 11 alpha hemisuccinate TME and Na125I with LPO in the presence of trace amount of hydrogen peroxide as the catalyst. The labelling efficiency obtained was (88.8%±4.7)% with a specific activity of about 400 μCi/μg. Purification by thin layer chromatography yielded a radiochemical purity of more than 90%. Determination of immunonoreactivity showed that the bound fraction was (56.3±3.9)%. The 125I labelled compound in ethanolic solution was shown to be stable for 3 months when stored at -20oC based on evaluation of its immunoreactivity and the non specific binding value. 125I labeled progesterone solution is phosphate buffer ready-for-use in radioimmunoassay were stable for 14 days when stored at 0oC. (author). 4 refs., 3 tabs., 3 figs

  10. In vitro root caries progression measured by 125I absorptiometry: comparison with chemical analysis

    International Nuclear Information System (INIS)

    Radiation from a 125I source and a non-image-forming detector was used for non-destructive measurements of root caries progression. Blocks were cut parallel to the cementum surface of unexposed human roots. These blocks were then individually demineralized in under-saturated calcium phosphate solutions over an 84-hour period. In order for the in vitro root surface demineralization to be followed, the changes in transmission (delta T) through the blocks were measured, by 125I absorptiometry, eight times during the course of the experiment. Chemical analyses of the calcium output (delta Ca) from the blocks into the demineralizing solutions were also performed, and the rate of demineralization (Vdem) was calculated from these values. The precision of 125I absorptiometry was calculated from 176 duplicate transmission measurements, and the coefficient of variation was found to be 0.20%. The correlation coefficient between delta T and total delta Ca for each of 22 cementum/dentin blocks ranged between r = 0.934 and r = 0.998. The progression of root hard-tissue lesions observed by these two methods and by the calculated Vdem was found to be proportional to the square and cubic roots of time. The study shows that 125I absorptiometry can be used for continuous non-destructive measurements of root hard-tissue demineralization in vitro

  11. Distribution of 125I-thyroxine in different organs and tissues of dietically obese rats

    International Nuclear Information System (INIS)

    The distribution of 125I-thyroxine (% dose/g tissue; tissue/plasma radioactivity ratio) was investigated in different tissues of 28-week-old obese Wistar rats. Obesity was induced by high-fat diet (HFD) and confirmed by carcass analysis; in heavy obese animals the relative and absolute fat content is increased twofold and threefold, respectively, compared to control rats fed on a low-fat diet (LFD). Heavy HFD rats exhibit diminished 125I-T4 distribution in the 'slow pool' (fat tissue, muscle) and unchanged values in the 'fast pool' (liver, kidneys) in comparison with LFD rats with low body weight. The differences in distribution presented here are not caused by the diet per se, but they are the consequence of the obesity of the animal, because no differences in the 125I-T4 distribution were found in the 125I-T4 between HFD and LFD rats with relatively equal body weight and body composition. The reduced T4 distribution in the fat tissue of obese rats is discussed in connection with possibly decreased lipolysis in this tissue and possible causal participation in the beginning of obesity. (author)

  12. Examination of the method for measuring plasma cortisol by 125I-cortisol radioimmunoassay

    International Nuclear Information System (INIS)

    The radioimmunoassay kit using 125I-cortisol for plasma cortisol was basically examined and was confirmed to have an excellent sensitivity, specificity, and reproducibility and to be very convenient. The present method was compared with the conventional flourescent method (Clark's method) and competitive protein binding analysis (CPBA), and a satisfactory correlation was obtained with both of them. (Chiba, N.)

  13. Cortisol decreases 2[125I] iodomelatonin binding sites in the duck thymus

    International Nuclear Information System (INIS)

    The immunosuppressive effect of chronic glucocorticoid treatment on 2[125I] iodomelatonin binding in the duck thymus was studied. Two-week-old ducks were injected intraperitoneally with either 1 mg of cortisol per day (experimental group) or an equivalent volume of vehicle (control group) in the middle of the light period for seven days. 2[125I] iodomelatonin binding assays were performed on thymic membranes. Cortisol injection reduced the body weight gain, size of the bursa of Fabricius and absolute weights of the primary lymphoid organs but had no effect on the spleen weights. The relative weights of the spleen were increased while those of the primary lymphoid organs were unchanged. The density of the thymus 2[125I] iodomelatonin binding sites was decreased while the affinity was not affected. The modulation of the thymic 2[125I] iodomelatonin binding sites by changes in the immune status of the duck suggests that these binding sites represent physiologically relevant melatonin receptors and that melatonin exerts its action on the lymphoid tissues directly. The authors findings support the hypothesis that the thymus is the target site for the immunomodulatory interactions between the pineal melatonin and the adrenal steroids. A possible inhibitory influence of adrenal steroids on the immuno-enhancing effect of melatonin is also suggested. 34 refs., 3 tabs

  14. Dopamine transport sites selectively labeled by a novel photoaffinity probe: 125I-DEEP

    International Nuclear Information System (INIS)

    The dopamine transporter was labeled using a photosensitive compound related to GBR-12909, 125I-1-[2-(diphenylmethoxy)ethyl]-4-[2- (4-azido-3-iodophenyl)ethyl]piperazine (125I-DEEP). 125I-DEEP bound reversibly and with high affinity to the dopamine transport protein in the absence of light and could be covalently attached to the protein following exposure to UV light. In rat striatal homogenates, 125I-DEEP was found to incorporate covalently into a protein with apparent molecular weight of 58,000 Da. The properties of this binding protein were characteristic of the dopamine transporter since covalent attachment could be inhibited by dopamine-uptake blockers with the proper pharmacological rank order of potencies. Covalent binding was also inhibited in a stereospecific manner by (+) and (-) cocaine, as well as other cocaine analogs. The protein was not found in the cerebellum. The dopamine transporter appears to exist in a glycosylated form since photoaffinity-labeled transport sites could adsorb to wheat germ-agglutinin and could be specifically eluted from the column by beta-N-acetylglucosamine

  15. Absolute intensity of internal bremsstrahlung from the electron capture decay of 125I

    International Nuclear Information System (INIS)

    The absolute intensity of the internal bremsstrahlung spectrum accompanying the electron capture decay of 125I has been measured and compared to the recent calculation of Suric et al. The measured intensity above the 1s end point is found to be (86±10)% of the calculated intensity

  16. Myocardial uptake of 125I-BMIPP in rats treated with adriamycin

    International Nuclear Information System (INIS)

    The ability of 125I-BMIPP in assessing myocardial mitochondrial function was investigated in rats treated with adriamycin (ADR). Intraperitoneal administration of ADR (4 mg/kg) for 6 days significantly decreased a ratio of heart/body weight as compared with the control rats. The light and electron microscopic analysis showed that ADR produced histological damages mainly in the mitochondria with minimal changes in the myofibril and nucleus. In the study of mitochondrial respiratory function, oxygen consumption with adding ADP, respiratory control ratio and ADP/O ratio were significantly lower in ADR rats than control rats. While myocardial uptake of 201TlCl was not different between the two groups, the uptake of 125I-BMIPP corrected by blood counts was significantly reduced in ADR rats (3.1±0.4 vs. 2.3±0.8, p125I-BMIPP. The observation suggests that 125I-BMIPP myocardial scintigraphy could be a useful method for determining mitochondrial function in patients with myocardial diseases. (author)

  17. Variation in 125I-insulin absorption and blood glucose concentration

    DEFF Research Database (Denmark)

    Lauritzen, Torsten; Faber, O K; Binder, C

    1979-01-01

    20 to 48 IU between patients. The insulin absorbed varied considerably within and between patients. The range of individual daily absorbed insulin varied from 19 to 104 per cent of the 125I-insulin dose. A significant correlation (p less than 0.05) was found between insulin absorption and blood...

  18. Effects of age and sex on 125I-β-CIT binding to DAT

    International Nuclear Information System (INIS)

    Objective: To investigate effects of age and sex on 125I-β-CIT binding to dopamine transporter (DAT). Methods: Detection of the differences in 125I-β-CIT binding kinetics in vivo between 6 week and 6 month old KM mice, and the differences of in vivo binding between female and male, and between 3 month and 12 month old SD rats.The animals were sacrificed 2 h after injection. Results: Uptake of 125I-β-CIT in the striatum, frontal cortex, parietal cortex, temporal cortex, occipital cortex, hippocampus, brain stem and whole brain in 6 week old mice was higher than that in 6 month old mice, and similar uptake pattern happened in between 3 month old and in 12 month old SD rats. In 12 months old SD rats, female rats had higher uptake in the striatum than male rats did. Conclusions: Young mice and rats have a higher uptake of 125I-β-CIT in the striatum than aged ones and female rats have a higher uptake than male ones do. This result indicates that the density of DAT in rat or mouse striatum may be reduced with aging

  19. Solid-phase receptor binding assay for 125I-hCG

    International Nuclear Information System (INIS)

    A solid-phase radioligand-receptor assay (RRA) to measure the binding of 125I-labelled human chorionic gonadotropin (125I-hCG) to target cell membranes has been developed. The binding of 125I-hCG to membranes immobilized on the wells of microtitration plates reached a maximum at about 3 hours at 37 degrees C, was saturable, displayed a high affinity (Ka = 2.4 X 10(9) M-1) and was specifically inhibited by unlabelled hCG. In comparison with RRAs carried out with membranes in suspension, the solid-phase RRA is significantly simpler and much faster to perform as it avoids centrifugation or filtration procedures. The solid-phase RRA was adapted profitably to process large numbers of samples at the same time. It proved particularly useful as a screening assay to detect anti-hCG monoclonal antibodies with high inhibitory activity for binding of 125I-hCG to its receptors

  20. Preparation and bio-distribution of 125I-fullerene pyrrolidine benzoyl nitrogen mustard

    International Nuclear Information System (INIS)

    The synthesized C60NM, after connecting with the stable iodine, was radiolabeled with iodine-125 through isotope exchanging. The bio-distribution of the radioiodinated compound in rats was studied. The results indicated that 125I-C60NM can target in lymphatic node and it has a good lympha targeting effect. (authors)

  1. Morbimortalidad de la endocarditis infecciosa asociada a dispositivos electrónicos implantables permanentes / Morbimortality of infective endocarditis associated with permanent cardiovascular implantable electronic devices

    Scientific Electronic Library Online (English)

    Gabriel, Pérez-Baztarrica; Flavio, Salvaggio; Norberto, Blanco; Héctor, Mazzetti; Ricardo, Levin; Alejandro, Botbol; Rafael, Porcile.

    2013-12-01

    Full Text Available La endocarditis infecciosa (EI) asociada a dispositivos electrónicos implantables permanentes (DEIP) es una complicación de baja frecuencia pero alta mortalidad sin el tratamiento adecuado. El avance sobre el conocimiento de esta patología y el desarrollo de estrategias terapéuticas como el diagnóst [...] ico precoz, manejo de antibióticos, técnicas de extracción, entre otras, han mejorado el pronóstico de estos pacientes. Los objetivos de este estudio fueron evaluar la morbimortalidad intrahospitalaria y alejada y analizar algunos factores que justifican las diferencias con los datos de la mortalidad publicada. Se estudiaron en forma retrospectiva pacientes entre marzo/2002 y marzo/2011 con diagnóstico de EI asociada a DEIP. Se analizaron características basales, diagnósticas, terapéuticas, evolución intrahospitalaria y alejada. Se incluyeron 26 casos atendidos en nuestro hospital, 23 de los cuales fueron remitidos desde otros centros para su diagnóstico y tratamiento. La edad promedio fue de 67,5 años. Todos los pacientes recibieron antibióticos durante seis semanas y se les retiró el sistema en forma completa; en el 95% de los pacientes por vía percutánea y en 2 pacientes se requirió estereotomía mediana, atriotomía y colocación de marcapasos epicardíaco. La mortalidad fue del 4% y en el seguimiento fue nula. La morbilidad intrahospitalaria fue del 31%. En el seguimiento alejado no hubo reinfecciones u otra complicación. Como conclusión la EI es un cuadro grave que presenta una morbilidad elevada con estadías hospitalarias prolongadas, pero la mortalidad es baja. La explicación podría estar en las técnicas percutáneas, experiencia, extracción completa, el tiempo del reimplante del nuevo dispositivo y el tratamiento precoz, entre otros factores. Abstract in english Infective endocarditis (IE) associated with permanent cardiovascular implantable electronic devices (CIEDs) is a complication of low frequency, but high mortality without adequate treatment. Progress on the knowledge of this disease and the development of therapeutic strategies such as early diagnos [...] is, antibiotic management and better extraction techniques, among others, have improved the prognosis of these patients. The objectives of this study were to evaluate the in-hospital and out-of-hospital morbidity, and analyze some factors that explain the differences among the published mortality data. Patients diagnosed with IE associated with CIEDs were studied, retrospectively, between March/2002 and March/2011. We analyzed baseline, diagnostic and therapeutic characteristics, and in-hospital and out-of-hospital courses of the disease. We included 26 cases treated in our hospital, 23 of whom were referred from other centers for diagnosis and treatment. The average age of the patients was 67.5 years. All patients received antibiotics for six weeks and underwent complete removal of the device system, in 95% of patients by percutaneous extraction and 2 patients required a median sternotomy, atriotomy and epicardial pacemaker placement. Mortality was 4% and the follow up mortality was zero. The in-hospital morbidity was 31%. In the follow-ups there were no reinfections or other complications. In conclusion, IE is a serious condition that has a high morbidity with prolonged hospital stays, but with a low mortality. The explanation may lie in the use percutaneous extraction techniques, experience, complete extraction of the device system, the time of reimplantation of the new device and early treatment, among other factors.

  2. Improved separation of 3H and 125I spectra in liquid scintillation counting by doping with thallium and lead

    International Nuclear Information System (INIS)

    Changes in the pulse height spectra of 3H and 125I in liquid scintillation counting have been studied when scintillator solutions were doped with heavy elements such as Tl and Pb. The possibility to use this method to improve the spectra separation of 3H and 125I in double labelling experiments has been investigated. This technique with doped scintillation solutions could also be used for efficient external counting of 125I. (author)

  3. Tyrosine A14[125I]monoiodoinsulin: preparation, biologic properties, and long-term stability

    International Nuclear Information System (INIS)

    125I-insulin was prepared by reacting 17.4 nmol porcine insulin (100 micrograms) with 5 mCi 125I (about 2.4 nmol) using the lactoperoxidase method. The reaction product was subjected to gel electrophoresis and the band containing A14 [125I]monoiodoinsulin was eluted. This preparation showed a specific activity of about 1.5 Ci/mumol as evaluated by radioimmunoassay and bioassay, i.e., about 75% of the theoretical maximum. The content of radioactive derivatives other than A14 monoiodoinsulin was less than 2%. The binding affinity of tracer A14 monoiodoinsulin to adipocytes, hepatocytes, and cultured human lymphocytes was twice as high as that of A19 monoiodoinsulin. Binding to antibodies was examined to 10 guinea pig anti-insulin sera. Three sera did not distinguish between the two tracers, whereas seven exhibited higher binding of the A14 tracer. A detailed analysis of one of the discriminating sera showed that the average affinity constant was about 2.5 times lower for the A19 tracer than for the A14 tracer. The A14 monoiodoinsulin tracer is remarkably stable. After 200 days the specific activity had declined to about half of its original value which is consistent with the hypothesis that the physical decay of [125I]monoiodoinsulin (T 1/2 equals 60 days) extinguishes the activity of the molecule without causing major damage of other molecules. By this time 96% of the radioactivity migrated with insulin when subjected to gel filtration on Sephadex G-50, 4% was in the void volume, and nothing in the total column volume or later. Binding to receptors was indistinguishable from that obtained at time zero. It is concluded that Tyr A14[125I]monoiodoinsulin represents an advance in biologic work as compared with previous tracers for insulin

  4. (/sup 125/I) radioiodinated metaraminol: A new platelet-specific labeling agent

    Energy Technology Data Exchange (ETDEWEB)

    Ohmomo, Y.; Yokoyama, A.; Kawai, K.; Arano, Y.; Horiuchi, K.; Tanaka, C.; Saji, H.; Torizuka, K.

    1985-03-01

    In our search for a platelet-specific labeling agent, metaraminol (MA), a low-toxic pharmaceutical for the treatment of hypotension and cardiogenic shock, attracted our attention. Its active incorporation and accumulation by platelets have been recognized. At first, the preparation of /sup 125/I radioiodinated metaraminol (/sup 125/I-MA) was carried out using the chloramine-T method. Then, upon the harvest of platelets as platelet-rich plasma (PRP), their labeling with this new radiopharmaceutical was easily performed by incubation for 10 min at 37/sup 0/C. The cell-labeling efficiency was dependent on cell density, reaching 63.0%+-3.1% at 2.4x10/sup 9/ cells/ml. The specific incorporation of /sup 125/I-MA by an active transport system similar to that of 5-hydroxytryptamine (5-HT) as well as by passive diffusion was demonstrated. In vitro studies, the unaltered state of /sup 125/I-MA-labeled platelets with their cellular functions fully retained was estimated. In vivo studies carried out in rabbits with induced thrombi in the femoral artery showed a rather rapid disappearance of the radioactivity from circulating blood, reaching a high thrombus-to-blood activity ratio of 19.8+-4.3 within 30 min of the administration of /sup 125/I-MA-labeled autologous platelets. Thus, with the potential availability of /sup 123/I, /sup 123/I-MA-labeled platelets appear to be a promising agent for thrombus imaging using single-emission computed tomography (CT) studies.

  5. Anti-tumor effects of Egr-IFN ? gene therapy combined with 125I-UdR radionuclide therapy

    International Nuclear Information System (INIS)

    Objective: To explore the anti-tumor effects of Egr-IFN? gene therapy combined with 125I-UdR radionuclide therapy in mice bearing H22 hepatocarcinoma and its mechanism. Methods: The recombinant plasmid pcDNAEgr-IFN? mixed with liposome was injected into tumor. 48 h later, 370 kBq 125I-UdR was injected into tumor. The tumor growth rates at different times were observed. After 3 d gene-radionuclide therapy, the concentration of IFN? in cytoplasm of H22 cells and cytotoxic activities of splenic CTL of the mice in different groups were examined. Results: The tumor growth rates of pcDNAEgr-IFN? + 125I-UdR group were obviously lower than those of control group, 125I-UdR group and pcDNAEgr-1 + 125I-UdR group 6-15 d after gene-radionuclide therapy. IFN? protein was found in cytoplasm of H22 cells in pcDNAEgr-IFN? + 125I-UdR group after 3 d gene-radionuclide therapy. Cytotoxic activity of splenic CTL in pcDNAEgr-IFN? + 125I-UdR group was significantly higher than that in the other groups (P125I-UdR radionuclide therapy are better than those of 125I-UdR therapy. (authors)

  6. Comparison of (/sup 125/I)HIPDm and (/sup 125/I)iodoantipyrine in quantifying regional cerebral blood flow in rats

    Energy Technology Data Exchange (ETDEWEB)

    Albright, R.E. Jr.; Friedman, A.H.; Fram, E.K.; Harbury, O.L.; Molter, B.A.; Skatoff, J.H.; Harris, C.C.; Coleman, R.E.; Drayer, B.P.

    1988-11-01

    We determined regional cerebral blood flow (rCBF) using (/sup 125/I)HIPDm (N,N,N'-trimethyl-N'-(2-hydroxy-3-methyl-5-iodobenzyl)-1,3-propanediamin e) and (/sup 125/I)iodoantipyrine autoradiography under control and pathologic conditions (hypercapnia (acidosis), hypocapnia (alkalosis), and disrupted blood-brain barrier) conditions in 35 rats. In control rats, HIPDm rCBF (indicator fractionation method, n = 5) was lower than the corresponding IAP rCBF (diffusible indicator method, n = 4), most notably in the infratentorial regions and subcortical nuclei. In hypercapnia, rCBF increased by 100% and 37% in the HIPDm (n = 5) and IAP (n = 5) groups, respectively. In hypocapnia, IAP rCBF (n = 4) decreased 34% but HIPDm rCBF (n = 4) did not change. Following disruption of the blood-brain barrier by intracarotid infusion of mannitol in eight rats, both radiotracers (HIPDm n = 4, IAP n = 4) showed decreased rCBF to regions of disruption as defined by trypan blue extravasation. Our work indicates that modeling HIPDm uptake to quantify rCBF using the indicator fractionation method will underestimate blood flow and that HIPDm kinetics are influenced by compartmental pH dynamics that will limit the accuracy of this method in quantifying rCBF in pathologic conditions.

  7. Fragmentation of Nimotuzumab for Preparation of 125I-F(ab’)2-Nimotuzumab as a Precursor for Preparing 125I-F(ab’)2-Nimotuzumab-NLS Radiopharmaceutical for Cancer Therapy

    International Nuclear Information System (INIS)

    Nimotuzumab is an anticancer agent which belongs to the inhibitor group of Epidermal Growth Factor Receptor (EGFR). This monoclonal antibody has a relatively high molecular weight which slows penetration on tumor cells, making it less attractive in imaging kinetics and potentially elicits antibodies responses. Therefore, in this study nimotuzumab was fragmented to form a bivalent antibody [F(ab’)2] and then labeled with 125I to form 125I-F(ab’)2-nimotuzumab which can be used further as a precursor for preparing 125I-F(ab’)2-nimotuzumab-NLS (NLS = nuclear localization sequence) radiopharmaceutical for radioimmunotherapy. The aims of this study was to obtain characteristics of 125I-F(ab’)2-nimotuzumab by comparing with the 125I labeled-intact nimotuzumab (125I-nimotuzumab). This study was initiated by purifying nimotuzumab by mean of dialysis. The purified nimotuzumab was then fragmented by using pepsin. The F(ab')2-nimotuzumab formed was then purified from its by-products which formed in fragmentation process by using a PD-10 column (consisted Sephadex G25). The intact nimotuzumab and its F(ab’)2 fragment were then labeled with the 125I to form 125I-nimotuzumab and 125I-F(ab’)2-nimotuzumab. The radiochemical purity are 98.27 % and 93.24 %, respectively. Stability test results show that, both 125I-nimotuzumab and 125I-F(ab’)2-nimotuzumab are more stable at 4 °C than at room temperature storage and 37 °C. (author)

  8. Fragmentation of Nimotuzumab for Preparation of 125I-F(ab’2-Nimotuzumab as a Precursor for Preparing 125I-F(ab’2-Nimotuzumab-NLS Radiopharmaceutical for Cancer Therapy

    Directory of Open Access Journals (Sweden)

    R.D. Haryuni

    2014-04-01

    Full Text Available Nimotuzumab is an anticancer agent which belongs to the inhibitor group of Epidermal Growth Factor Receptor (EGFR. This monoclonal antibody has a relatively high molecular weight which makes slow penetration on tumor cell, as concequence, it is less attractive in imaging kinetics, and potentially elicits antibodies respons. Therefore in this study nimotuzumab was fragmented to form bivalent antibody [F(ab’2] and then labeled with 125I to form 125I-F(ab’2-nimotuzumab which can be used further as a precursor for preparing 125I-F(ab’2-nimotuzumab-NLS (NLS = nuclear localizing sequences radiopharmaceutical for radioimmunotherapy. The aims of this study were to obtain characteristics of 125I-F(ab’2-nimotuzumab by comparing with the 125I labeled-intact nimotuzumab (125I-nimotuzumab. This study was initiated by purifying nimotuzumab by mean of dialysis. The purified nimotuzumab was then fragmented by using pepsin. The F(ab'2-nimotuzumab formed was then purified from its by-products which formed in fragmentation process by using a PD-10 column (consisted Sephadex G25. The intact nimotuzumab and its F(ab’2 fragment were then labeled with the 125I to form 125I-nimotuzumab and 125I-F(ab’2-nimotuzumab. The radiochemical purity are 98.27 % and 93.24 % ,respectively. Stability test results show that, both of 125I-nimotuzumab and 125I-F(ab’2-nimotuzumab more stable at 4 °C than at room temperature storage and 37 °C

  9. The incidence of radioepidermitis and the dose-response relationship in parotid gland cancer patients treated with 125I seed brachytherapy. Incidence of radioepidermitis and the dose-response relationship

    International Nuclear Information System (INIS)

    We studied the incidence and dose-response relationship of radioepidermitis in parotid gland carcinoma patients treated with [125I] seed brachytherapy in the hopes of designing an optimized pre-implant treatment plan that would reduce the incidence and severity of radioepidermitis in patients receiving this therapy. Between January 2007 and May 2010, 100 parotid gland cancer patients were treated postoperatively with [125I] seed brachytherapy. The matched peripheral dose (MPD) was 80-140 Gy, and [125I] seed activity was 0.7-0.8 mCi. The mean dose delivered to the skin was calculated in the post-implant CT on day 0 following implantation. Grades of acute and late dermatitis were evaluated at 2, 6, 12, and 18 months post-implantation. Most patients experienced grade 0-2 acute and late skin side effects (86 and 97 %, respectively), though a small subset developed severe complications. Most grade 1-3 effects resolved within 6 months of implantation, though some grade 1-3 effects and all grade 4 effects remained unchanged throughout the 18-month follow-up period. Grade 3 and 4 effects were most prominent (75 and 25 %, respectively) with doses of 110-140 Gy; doses higher than 140 Gy produced only grade 4 effects. [125I] seed brachytherapy produced acceptable levels of acute and late radioepidermitis with a good clinical outcome. A mean dose under 100 Gy delivered to the skin was safe, though doses of 110-140 Gy should be given with caution and extra monitoring; doses greater than 140 Gy are dangerous and likely to produce grade 4-5 effects. (orig.)

  10. In vitro characterization of the influx of 3-[{sup 125}I]iodo-L-{alpha}-methyltyrosine and 2-[{sup 125}I]iodo-L-tyrosine into U266 human myeloma cells: Evidence for System T transport

    Energy Technology Data Exchange (ETDEWEB)

    Lahoutte, T. E-mail: nucglet@az.vub.ac.be; Caveliers, V.; Dierickx, L.; Vekeman, M.; Everaert, H.; Mertens, J.; Bossuyt, A

    2001-02-01

    The aim of this study was to investigate the cellular uptake mechanisms responsible for the accumulation of 3-[{sup 125}I]iodo-L-{alpha}-methyltyrosine ({sup 125}I-3-IMT) and 2-[{sup 125}I]iodo-L-tyrosine ({sup 125}I-2-IT), two radiotracers for metabolic tumor imaging, using single-photon emission tomography, into U266 human myeloma cancer cells. Time course and concentration dependency of {sup 125}I-3-IMT uptake was assessed. Kinetic parameters were calculated using an Eadie Hofstee plot. A set of competitive inhibitors of the main amino acid transport systems was used for the discrimination of the transporters responsible for the uptake of {sup 125}I-3-IMT and {sup 125}I-2-IT. Protein incorporation of both tracers was determined using acid precipitation. The measured maximum velocity for {sup 125}I-3-IMT transport was 4.199 nmol per mg protein 20 s{sup -1}, and the Michaelis constant was 107.9 {mu}M. Addition of 2-aminobicyclo[2,2,1]heptane-2-carboxylic acid (BCH), a competitive inhibitor of System L, reduced the influx by 39.0{+-}3.3% for {sup 125}I-3-IMT and 66.3{+-}0.9% for {sup 125}I-2-IT. The BCH-insensitive influx was further reduced by Tryptophan (Trp) by 43.8{+-}3.5% for {sup 125}I-3-IMT and 15.3{+-}1.3% for {sup 125}I-2-IT. This suggests involvement of System T transport. We measured <2% of radioactivity in the acid precipitable fractions of both tracers with no increase in time. We conclude that the influx of {sup 125}I-3-IMT and {sup 125}I-2-IT into U266 human myeloma cells is mediated by both System L and System T amino acid transporters. The kinetic parameters suggest that elevated plasma levels of aromatic amino acids will reduce {sup 123}I-3-IMT uptake in myeloma patients. Both tracers do not enter protein synthesis significantly.

  11. The tumor control probability model for transperineal permanent prostate brachytherapy and prostate-specific antigen failure free survival

    Science.gov (United States)

    Prete, James John

    1999-12-01

    The studies proposed were designed to investigate the relationship between transperineal permanent prostate implant quality, as modeled by the radiobiologicalquantifier of implant quality, tumor control probability (TCP), and treatment efficacy, as measured by prostatespecific antigen (PSA) failure free survival. It was hypothesized that TCP could be useful in identifying which patients, or group of patients, might be at an increased risk for treatment failure among patients receiving 125I transperineal permanent prostate brachytherapy (TPPB) as the sole modality of treatment for early or intermediate stage prostatic carcinoma. The formal statement of hypothesis was that the linear- quadratic tumor control probability model for monotherapeutic 125I transperineal permanent prostate brahytherapy correlates with prostate- specific antigen failure free survival. The specific aims were: [i]to implement the TCP model in a computerized treatment planning system for TPPB, using the recently recommended dose calculation formalism and benchmark data presented in AAPM TG43 and validate it, [ii]to compute and examine the relationship between TCP and PSA failure free survival for patients receiving monotherapeutic 125I TPPB, [iii]to investigate the influence of the definition of PSA failure on the relationship between TCP and PSA failure free survival rates, and [iv]to develop a method for improving the TCP model. The conclusions were: [i]the model as implemented using AAPM TG43 formalism, produced results which were similar to that calculated by the original model. TCP was demonstrated to correlate strongly and similarly with underdosed prostate volume in comparison to data published from the original model, [ii]an analysis of 125I implants demonstrated that patients stratified into the high TCP group had PSA failure free survival rates which were superior to the rates for patients in the low TCP group, regardless of which of the five definitions of PSA failure was applied to the study group, however, [iii]when different definitions of PSA failure were used to assess treatment efficacy, significantly different rates of PSA failure free survival were observed. Additionally, [iv]a method for calibrating the TCP model to produce a distribution of TCP's which more closely matched the calculated PSA failure free survival rates was derived.

  12. Synthesis and binding characteristics of N-(1-naphthyl)-N'-(3-[125I]-iodophenyl)-N'-methylguanidine ([125I]-CNS 1261): a potential SPECT agent for imaging NMDA receptor activation

    International Nuclear Information System (INIS)

    N-(1-Naphthyl)-N'-(3-[125I]-iodophenyl)-N'-methylguanidine ([125I]-CNS 1261) was synthesized as a potential radioligand to image N-methyl-D-aspartate (NMDA) receptor activation. [125I]-CNS 1261 was prepared by radioiodination of N-(1-naphthyl)-N'-(3-tributylstannylphenyl)-N'-methylguanidine using Na125I and peracetic acid. [125I]-CNS 1261 uptake in vivo reflected NMDA receptor distribution in normal rat brain, whereas in ischemic rat brain, uptake was markedly increased in areas of NMDA receptor activation. Radiolabeled CNS 1261 appears to be a good candidate for further development as a single photon emission computed tomography tracer in the investigation of NMDA receptor activation in cerebral ischemia

  13. PSA bounce after {sup 125}I-brachytherapy for prostate cancer as a favorable prognosticator

    Energy Technology Data Exchange (ETDEWEB)

    Engeler, Daniel S.; Schwab, Christoph; Schmid, Hans-Peter [Cantonal Hospital St. Gallen, Department of Urology, St. Gallen (Switzerland); Thoeni, Armin F. [Lindenhofspital Berne, Department of Radiation Oncology, Berne (Switzerland); Hochreiter, Werner [Hirslanden Klinik Aarau, Department of Urology, Aarau (Switzerland); Prikler, Ladislav [Klinik Uroviva Buelach, Department of Urology, Buelach (Switzerland); Suter, Stefan [Cantonal Hospital Zug, Department of Urology, Zug (Switzerland); Stucki, Patrick [Cantonal Hospital Lucerne, Department of Urology, Lucerne (Switzerland); Schiefer, Johann; Plasswilm, Ludwig; Putora, Paul Martin [Cantonal Hospital St. Gallen, Department of Radiation Oncology, St. Gallen (Switzerland)

    2015-10-15

    Permanent low-dose-rate brachytherapy (BT) with iodine 125 is an established curative treatment for localized prostate cancer. After treatment, prostate-specific antigen (PSA) kinetics may show a transient rise (PSA bounce). Our aim was to investigate the association of PSA bounce with biochemical control. Patients treated with BT in Switzerland were registered in a prospective database. Only patients with a follow-up of at least 2 years were included in our analysis. Clinical follow-up and PSA measurements were assessed after 1.5, 3, 6, and 12 months, and annually thereafter. If PSA increased, additional follow-up visits were scheduled. Cases of PSA bounce were defined as a rise of at least 0.2 ng/ml above the initial PSA nadir with a subsequent decline to or below the initial nadir without treatment. Biochemical failure was defined as a rise to nadir + 2 ng/ml. Between March 2001 and November 2010, 713 patients with prostate cancer undergoing BT with at least 2 years of follow-up were registered. Median follow-up time was 41 months. Biochemical failure occurred in 28 patients (3.9 %). PSA bounce occurred in 173 (24.3 %) patients; only three (1.7 %) patients with PSA bounce developed biochemical failure, in contrast to 25 (4.6 %) patients without previous bounce (p < 0.05). The median time to bounce was 12 months, the median time to biochemical failure was 30 months. The median bounce increase was 0.78 ng/ml. Twenty-eight patients with bounce (16.5 %) had a transient PSA rise of + 2 ng/ml above the nadir. In most cases, an early increase in PSA after BT indicates PSA bounce and is associated with a lower risk of biochemical failure. (orig.) [German] Die permanente Low-dose-rate-Brachytherapie (BT) mit {sup 125}I ist ein etabliertes kuratives Verfahren bei lokalisiertem Prostatakarzinom. Posttherapeutisch koennen die PSA-Konzentrationen einen voruebergehenden Anstieg zeigen (Bounce-Phaenomen). Untersucht werden sollte ein moeglicher Zusammenhang mit der biochemischen Kontrolle. Patienten, die eine BT in der Schweiz bekommen hatten, wurden in einer prospektiven Datenbank erfasst. Nur Patienten mit mindestens 2 Jahren Nachsorge wurden in die Studie eingeschlossen. Klinische Verlaufskontrollen mit PSA-Messungen erfolgten nach 1, 5, 3, 6 und 12 Monaten sowie anschliessend jaehrlich. Bei einer PSA-Erhoehung wurden weitere Termine vereinbart. Der PSA-Bounce wurde definiert als ein Anstieg des PSA-Wertes um mindestens 0,2 ng/ml ueber den initialen PSA-Nadir mit anschliessendem Absinken auf diesen Wert oder tiefer ohne Therapie. Biochemisches Versagen wurde definiert als Nadir+2ng/ml. Eingeschlossen wurden 713 Patienten, die zwischen 03/2001 und 11/2010 eine BT und mindestens 2 Jahre (mediane Nachsorgedauer 41 Monate) Nachsorge erhalten hatten. Ein biochemisches Versagen zeigte sich bei 28 Patienten (3,9 %). Bei 173 (24,3 %) Patienten konnte ein Bounce beobachtet werden, nur 3 (1,7 %) entwickelten anschliessend ein biochemisches Versagen. Dagegen entwickelten 25 (4,6 %) Patienten ohne Bounce ein biochemisches Rezidiv (p < 0,05). Die mediane Zeit bis zum Bounce betrug 12 Monate, die mediane Zeit bis zum biochemischen Versagen 30. Der mediane PSA-Anstieg beim Bounce war 0,78 ng/ml. Achtundzwanzig Patienten (16,5%) mit einem Bounce hatten einen temporaeren PSA-Anstieg von + 2 ng/ml ueber den Nadir. In den meisten Faellen war ein frueher PSA-Anstieg nach BT mit einem Bounce verbunden; dieser ist mit einem niedrigeren Risiko fuer ein biochemisches Rezidiv assoziiert. (orig.)

  14. Application of different 125I tracers in radioimmunoassays of estradiol-17?

    International Nuclear Information System (INIS)

    Some different 125I-labelled estradiol tracers were produced by direct radioiodizing of estradiol and also of the histamine and tyramine conjugates of estradiol-3-carboxymethylether (E2-3-CM) by means of the chloramine-T method. The linkage properties of these tracers were investigated in relation to the 3H-labelled estradiol opposite to the antisera, which were produced against the cow serum albumin (RSA) conjugates of E2-3-CM and estradiol-6-carboxymethyloxime (E2-6-CMO). As suitable system for the radioimmunological estradiol determination could be revealed 4-125I-iodine estradiol in connection with one antiserum in each case of the radioligand antiserum combinations against E2-3-CM-RSA- and E2-6-CMO-RSA-conjugate. The double antibody method is used for separation in optimized RIA systems. The first and the second antibody reaction take place simultaneously. (author)

  15. Enzymatic iodination of salivary proteins by the 125I-lactoperoxidase system

    International Nuclear Information System (INIS)

    Purified milk lactoperoxidase and endogenous human salivary peroxidase were used to label the proteins of whole mouth saliva with [125I]iodide. The proteins were then analyzed by isoelectric focusing or they were subjected to one-dimensional polyacrylamide gel electrophoresis at pH 8.4. The radioactivity of the resolved protein fractions was determined. There were three to four major and four to five minor areas of radioactivity which were carried together with more or less distinctive fractions. Amylase and albumin were shown to be the most effective in binding [125I]iodide. No significant differences were observed in the iodination patterns of salivary proteins iodinated in the presence of endogenous saliva peroxidase and those iodinated in the presence of added milk lactoperoxidase. Hydrogen peroxide was necessary for iodination to take place. The significance of iodoproteins and the role of salivary peroxidases in the nonthyroidal metabolism of iodine are discussed. (author)

  16. Histoautoradiography of central nervous system in rats with generalized tetanus due to 125I-toxin

    International Nuclear Information System (INIS)

    Rats were injected i.v. with 125I-tetanus toxin. In autoradiographs of the spinal cord radioactivity was found over the pericarya and in the surroundings of the motoneurones whereas grain density was less over their nuclear region. In addition, pericarya in the lateral horn of the thoracic region and also the bipolar cells of the spinal ganglia contained radioactivity. The central part and the dorsal horns of spinal cord, and the white substance did not show any appreciable radioactivity. Within the medulla oblongata, clusters of large cells representing motor nuclei, as well as some fibre tracts close to them, contained 125I. Forebrain and cerebellum remained free. According to its histoautoradiographic appearance, generalized tetanus can be described best as a combination of multiple local tetani. (orig.)

  17. Preparation of 125I-Ochratoxin and its biodistribution in rats

    International Nuclear Information System (INIS)

    Ochratoxin was successfully labelled with 125I in presence of chloramine-T (Ch-T) as an oxidizing agent. The effects of different reaction parameters such as reaction time, oxidizing agent concentration, ph and concentration of ochratoxin have been investigated. Separation and identification of the labelled products were achieved by means of thin layer chromatography (TLC) and gel chromatography using sephadex G-25 column. The labelled product was orally administrated to rats and the accumulation of radioactivity in the body at definite time intervals was examined. The accumulation of the radioactivity was pronounced at the kidney, the liver, the blood and digestive intestinal tract. The produced 125I-ochratoxin was found stable in-vivo against biological decomposition

  18. Measured human thyroid 125I activities deriving from waste discharges in the Thames Valley area, UK

    International Nuclear Information System (INIS)

    Over the period 1984-9, 260 excised human thyroids from five areas along the Thames Valley were measured for 125I. The radioiodine derives from waste discharges via the drinking water. Activity concentration increased 4-fold during this period in those areas deriving drinking water from the River Thames. The maximum recorded thyroid activity was 203 mBq g-1 (dry wt) giving a calculated thyroid dose-equivalent of 7.2 μSv y-1 assuming a steady, chronic situation. The total collective annual dose-equivalent to the thyroids of the population in the Thames Valley during 1989 from the uptake of 125I arising from waste disposal was about 6 man-Sv. This cannot be expected to produce any detectable increase in the incidence of thyroid cancer. (Author)

  19. Behaviour of homologous 125I fibrinogen after thrombin and ancrod infusion in rabbits

    International Nuclear Information System (INIS)

    The behaviour of radioactively labelled fibrinogen after infusion of thrombin or ancrod is investigated. Common factors and differences in the behaviour of fibrinogen after infusion of these two enzymes, which act proteolytically on the fibrinogen, are dealt with. Rabbits received an i.v. injection of homologous 125I-fibrinogen 3 days before ancrod or thrombin infusion. On the day of the experiments, one group of animals received an ancrod infusion (1.5 U/kg body weight for 30 minutes), the other a thrombin infusion (600 U/kg body weight for 60 minutes). Intravenous ancrod and thrombin infusions lowered the fibrinogen level to 30% or 50% of the initial value due to intravascular coagulation. About 50% of the 125I fibrinogen was transformed after ancrod exposure into a non-coagulating fraction of fibrinogen derivatives which produces no fibrinolytic decomposition products. (orig./AJ)

  20. Myocardial fatty acid metabolism in diabetic mice with 125I-BMIPP.

    Science.gov (United States)

    Oshima, M; Higashi, S; Kikuchi, Y; Shirai, T; Yokokawa, T; Kaminaga, T; Yasukochi, H; Furui, S

    1998-06-01

    In patients with diabetes mellitus, the existence of diabetic cardiomyopathy was substantiated. This study was undertaken to evaluate the myocardiac fatty acid metabolism of diabetic mice (n = 21) and controls (n = 21) in 125I-BMIPP in fasted and unfasted states. 125I-BMIPP of 370 kBq was given and thirty minutes later, animals from both groups were killed. Samples of hearts, liver and other organs were removed, weighed and then counted in a scintillation counter. The percent injected dose/g of hearts of diabetic mice was significantly reduced compared to controls in unfasted (p < 0.05) and fasted (p < 0.01) groups. These findings may reflect impaired fatty acid utilization of the hearts in diabetic mice compared to controls. PMID:9673713

  1. /sup 125/I-. beta. -iodo-D-alanine synthesis, biodistribution and antimicrobial activity

    Energy Technology Data Exchange (ETDEWEB)

    Shiue, C.Y.; Gallagher, B.M.; Wolf, A.P.

    1981-06-01

    Methyl N-carbobenzoxy-..beta..-iodo-D-alaninate (1) served as an intermediate to synthesize methyl ..beta..-iodo-D-alaninate (2) and ..beta..-iodo-D-alanine (3). The /sup 125/I-labeled compound 1 was synthesized by the melt method and used to synthesize /sup 125/I-labeled compounds 2 and 3. Compound 3 was shown to be substrate for D-amino acid oxidase. It was also shown that compounds 2 and 3 were rapidly eliminated from normal mammalian tissues and that compound 3 inhibited the Escherichia coli growth in a dose-dependent manner at 100-500 ..mu../ml while compound 2 showed no effect at 500 ..mu..g/ml level. Therefore, it was suggested that compound 3 may serve as an abcess localizing agent.

  2. Myocardial fatty acid metabolism in diabetic mice with {sup 125}I-BMIPP

    Energy Technology Data Exchange (ETDEWEB)

    Oshima, Motoo; Higashi, Shizuka; Kikuchi, Yoshirou; Shirai, Tatsuo; Yokokawa, Tokuzou; Kaminaga, Tatsuro; Yasukochi, Hiroshi; Furui, Shigeru [Teikyo Univ., Tokyo (Japan). Faculty of Medicine

    1998-06-01

    In patients with diabetes mellitus, the existence of diabetic cardiomyopathy was substantiated. This study was undertaken to evaluate the myocardiac fatty acid metabolism of diabetic mice (n=21) and controls (n=21) in {sup 125}I-BMIPP in fasted and unfasted states. {sup 125}I-BMIPP of 370 kBq was given and thirty minutes later, animals from both groups were killed. Samples of hearts, liver and other organs were removed, weighed and then counted in a scintillation counter. The percent injected dose/g of hearts of diabetic mice was significantly reduced compared to controls in unfasted (p<0.05) and fasted (p<0.01) groups. These findings may reflect impaired fatty acid utilization of the hearts in diabetic mice compared to controls. (author)

  3. Labeling of platelet surface proteins with 125I by the iodogen method

    International Nuclear Information System (INIS)

    A procedure for the 125I-iodination of platelet suspensions is described. The procedure utilizes Iodogen, a solid-phase oxidizing agent similar to chlorimine-T. Platelets were labeled under a variety of conditions, including in the presence of 0.1% albumin, and showed between 7 and 28% incorporation of 125I. Best labeling results were obtained at low platelet concentration (3-5 x 108 platelets/ml), short reaction times (15 min), and wit 2-ml glass vials coated with 100 ?g of Iodogen. Analysis of the labeled platelet proteins by sodium dodecyl sulfate-polyacrylamide gel electrophoresis followed by autoradiography revealed that the same major protein bands were labeled by this procedure as were labeled by the lactoperoxidase procedure. At low platelet concentrations, the Iodogen procedure gives twice the amount of iodine incorporation

  4. Myocardial fatty acid metabolism in diabetic mice with 125I-BMIPP

    International Nuclear Information System (INIS)

    In patients with diabetes mellitus, the existence of diabetic cardiomyopathy was substantiated. This study was undertaken to evaluate the myocardiac fatty acid metabolism of diabetic mice (n=21) and controls (n=21) in 125I-BMIPP in fasted and unfasted states. 125I-BMIPP of 370 kBq was given and thirty minutes later, animals from both groups were killed. Samples of hearts, liver and other organs were removed, weighed and then counted in a scintillation counter. The percent injected dose/g of hearts of diabetic mice was significantly reduced compared to controls in unfasted (p<0.05) and fasted (p<0.01) groups. These findings may reflect impaired fatty acid utilization of the hearts in diabetic mice compared to controls. (author)

  5. Clinical application of esophageal stent loaded with 125I seeds: recent progress in research

    International Nuclear Information System (INIS)

    Esophageal cancer is a common malignant tumor. Most patients have already in the late stage of the disease when the diagnosis is confirmed and have lost the surgery chance. In recent years, esophageal stent has been widely applied in the treatment of esophageal stenosis caused by esophageal cancer. The clinical experience shows that the esophageal stent can effectively solve the problem of dysphagia. However, the ordinary esophageal stent has no therapeutic effect on the esophagus tumor. The esophageal stent loaded with 125I seeds can not only solve the dysphagia problem but also can treat the primary esophagus cancer with its brachytherapy effect. This article aims to review the clinical application and the up-to-date research progress of the esophageal stent loaded with 125I seeds. (authors)

  6. 7-amino-8-[125I-ketanserin ([125I]AMIK), a highly sensitive, serotonin-S2 receptor ligand

    International Nuclear Information System (INIS)

    The results demonstrate that :125I:AMIK is a very potent, specific serotonin-S2 receptor ligand with a very good ratio of specific to non-specific binding. This makes it the ligand of choice to study serotonin-S2 receptors in those tissues having a low receptor content. Apart from its high affinity for serotonin-S2 receptors, the compound also shows nanomolar affinity for histamine-H1 receptors. This dual affinity is not a disadvantage if selective displacers (such as methysergide) are used to define specific serotonin-S2 receptor binding. Eventually, the new compound may also be useful to study histamine-H1 receptors. (author)

  7. A study of relative regional cerebral blood flow using N-isopropyl-p-[125I]-iodoamphetamine (125I-IMP) in carbon monoxide exposed rats

    International Nuclear Information System (INIS)

    The influence of carbon monoxide (CO) exposure on regional cerebral blood flow (r-CBF) in rat brain was studied using autoradiography and 125I-IMP. Fuji computed radiography (FCR) was used to obtain improved autoradiograms in this study. R-CBF was determined in a relative measure by calculating hippocampus/cortex and putamen/cortex ratios of RI accumulation from the autoradiogram using a densitometer. Comparison of autoradiograms with pathological findings in the area of the hippocampus and putamen yield the following results. In the animals that were exposed to 6400 ppm or 10000 ppm of CO for 30 minutes, and then were followed up for 2 weeks without further exposure, r-CBF was decreased but no pathological changes occurred. In the animals that were exposed to 6400 ppm or 10000 ppm of CO, and then were followed up for 4 weeks without further exposure, pathological changes appeared. In animals exposed to 3200 ppm of CO, the r-CBF tended to recover after 4 weeks. Furthermore, following exposure to 6400 ppm of CO, the r-CBF tended to recover after 2 weeks but went down again after 4 weeks. A turning point of at which r-CBF recovers or dose not recover, and whether neural cell's pathological changes appear or do not appear was thought to lie somewhere between 3200 ppm and 6400 ppm. The nuclear medicine techniques and autoradiography with 125I-IMP were very useful in the detection of disorders of r-CBF before the appearance of pathological changes. (author)

  8. 125I-labeled crosslinking reagent that is hydrophilic, photoactivatable, and cleavable through an azo linkage

    International Nuclear Information System (INIS)

    A radioactive crosslinking reagent, N-[4-(p-azido-m-[125I]iodophenylazo)benzoyl]-3-aminopropyl-N'-oxysulfosuccinimide ester, has been synthesized. The reagent is photoactivatable, water-soluble, cleavable through an azo linkage, and labeled with 125I at the carrier-free specific activity of 2000 Ci/mmol. Any protein derivatized with the reagent is thus converted into an 125I-labeled photoaffinity probe. Crosslinks are formed following photolysis with 366-nm light, and cleavage by sodium dithionite results in the donation of radioactivity to the distal partner in crosslinked complexes. The newly labeled proteins are then analyzed by gel electrophoresis and autoradiography. The compound was prepared by iodination of N-[4-(p-aminophenylazo)benzoyl]-3-aminopropionic acid using carrier-free Na125I and chloramine-T, followed by azide formation and conversion to the water-soluble sulfosuccinimide ester. As a model system, protein A-Sepharose was derivatized with the reagent under subdued light. Each derivatized protein A molecule contained only one crosslinker. The derivatized protein A-Sepharose was then photolyzed in the presence of human serum and subsequently treated with sodium dithionite. Analysis of the serum by gel electrophoresis revealed that 1.1% of the radioactive label originally present on the protein A-Sepharose was transferred to the heavy chain of IgG, which was the most intensely labeled protein in the gel. The next most intensely labeled protein was IgG light chain, which incorporated radioactivity that was lower by a factor of 3.6 than that of the heavy chain. 36 references, 3 figures

  9. Preclinical pharmacological study on 125I-ADAM as a serotonin transporter ligand

    International Nuclear Information System (INIS)

    Purpose: To evaluate the new ligand: 2-((2-((Dimethylamino)methyl)phenyl)thio) -5-iodophenylamine (125I-ADAM) as a serotonin imaging agent. Methods: Biological evaluations were performed in rats and mice. Results: Biodistribution studies in rats showed that the initial uptake of 125I-ADAM in the brain was high (1.265ID/organ at 2 min postinjection), and consistently displayed the highest binding (between 60-240 min post injection) in hypothalamus, a region with the highest density of SERT. The specific binding((T/CB)-l) of 125I-ADAM in hypothalamus were 3.38, 3.62 and 4.36 at 60 min, 120 min and 240 min postinjection, respectively. The (T/CB)-I was significantly blocked by pretreatment with paroxetine, which is known as a serotonin site reuptake inhibitor, while other nonselective competing drug Ketanserin, showed no block effect. The rat brain autoradiography and analysis showed that there was high 131I-ADAM uptake in hypothalamus, the ratio of hypothalamus/cerebellum was significantly reduced from 7.94±0.39 to 1.30±0.56 by pretreatment with paroxetine at 60 min postinjection. Blood clearance kinetics was performed in rats, and the initial half-life of 13.79 min and late half-life of 357.14 min were obtained. The kinetic equation is: C=3.614e-0.0725t + 1.0413e-0.0028t. The thyroid uptake was 0.129%ID and 1.541%ID at 2 min and 120 min postinjection , respectively, suggesting that in vivo deiodination maybe the major route of metabolism. Toxicity trial showed that the dose per kilogram administered to mice was 1000 times greater than that to humans, assuming a weight of 50 kg. Conclusion: These data suggest that 125I-ADAM may be useful for SPECT imaging of SERT binding sits in the brain. (authors)

  10. Synthesis and biological evaluation of 125I-erythropoietin as a potential radiopharmaceutical agent for tumours

    Directory of Open Access Journals (Sweden)

    Gonçalo dos Santos Clemente

    2011-03-01

    Full Text Available Erythropoietin (EPO is a glycoprotein hormone responsible for regulating erythropoiesis. Expression of EPO and EPO receptors (EPOr has recently been demonstrated in some neoplastic cell lines and tumours, suggesting a potential new target for therapy. In this work, EPO was labeled with iodine-125 using the lactoperoxidase method, known to prevent damage to protein during radioiodination, and labeling conditions were optimized. In vitro stability studies have shown that 125I-EPO is radiochemically stable for 20 days after radiolabeling. In vitro cell binding studies have demonstrated very low binding (A eritropoetina (EPO é um hormônio glicoprotéico responsável pela regulação da eritropoese. Recentemente foi demonstrado que os receptores de EPO (EPOr estão expressos em algumas linhas celulares neoplásicas, o que sugere a sua potencialidade como um novo alvo terapêutico. Neste trabalho a EPO foi radiomarcada com iodo-125 através do método da lactoperoxidase, menos agressivo para a viabilidade biológica das proteínas. A 125I-EPO revelou ser radioquimicamente estável durante 20 dias após a síntese. Um estudo biológico in vitro em linhas celulares tumorais demonstrou que a 125I-EPO apresenta uma ligação muito fraca (<2%, tanto em células normais como nas linhagens tumorais testadas. A biodistribuição em camundongos saudáveis apresentou taxas de fixação relativamente maiores nos órgãos excretores e a tireóide revelou ser o órgão crítico, o que pode indicar a dissociação in vivo da 125I-EPO. No estudo em camundongos com melanoma induzido a fixação no tumor foi residual. Serão, no entanto, necessários novos estudos em outras linhagens tumorais para entender o seu processo de internalização e ligação nas células. Estudos da EPO radiomarcada com carbono-11 poderão também revelar-se interessantes, já que neste método há maior probabilidade da atividade biológica ser preservada.

  11. Differential dose contributions on total dose distribution of 125I brachytherapy source

    OpenAIRE

    Camgöz, B.; Ye?in, G.; Kumru, M.N.

    2010-01-01

    This work provides an improvement of the approach using Monte Carlo simulation for the Amersham Model 6711 125I brachytherapy seed source, which is well known by many theoretical and experimental studies. The source which has simple geometry was researched with respect to criteria of AAPM Tg-43 Report. The approach offered by this study involves determination of differential dose contributions that come from virtual partitions of a massive radioactive element of the studied source to a total ...

  12. Synthesis and biological evaluation of 125I-erythropoietin as a potential radiopharmaceutical agent for tumours

    OpenAIRE

    Gonçalo dos Santos Clemente; Vera Lúcia Serra Duarte

    2011-01-01

    Erythropoietin (EPO) is a glycoprotein hormone responsible for regulating erythropoiesis. Expression of EPO and EPO receptors (EPOr) has recently been demonstrated in some neoplastic cell lines and tumours, suggesting a potential new target for therapy. In this work, EPO was labeled with iodine-125 using the lactoperoxidase method, known to prevent damage to protein during radioiodination, and labeling conditions were optimized. In vitro stability studies have shown that 125I-EPO is radiochem...

  13. Localization of 125I-insulin binding sites in the rat hypothalamus by quantitative autoradiography

    International Nuclear Information System (INIS)

    In vitro autoradiography and computer video densitometry were used to localize and quantify binding of 125I-insulin in the hypothalamus of the rat brain. Highest specific binding was found in the arculate, dorsomedial, suprachiasmatic, paraventricular and periventricular regions. Significantly lower binding was present in the ventromedial nucleus and median eminence. The results are consistent with the hypothesis that insulin modulates the neural regulation of feeding by acting at sites in the hypothalamus. (author)

  14. Specific absorption in vivo of the [125 I] insulin by the Chrysemys dorbigni turtle thyroid

    International Nuclear Information System (INIS)

    Based on researches that demonstrate the presence of insulin receptor sites in hypophysis and supra renal, we investigate this hormone specific absorption by the thyroid gland. We used adult males and females Chrysemys dorbigni turtles. It was used a in vivo method consisting of [125 I] (2 x 106 cpm/Kg) insulin intra-aorta administration, and counting of the radioactivity in the gland and blood. 101 refs., 10 figs., 2 tabs

  15. Cytocidal effect of rifamycin derivatives on ascites tumor cells: studies with (/sup 125/I) iododeoxyuridine

    Energy Technology Data Exchange (ETDEWEB)

    Hughes, A.M.; Calvin, M.

    1979-01-01

    The cytotoxicity of 2 rifamycin derivatives, rifazone-8/sub 2/ and rifampicin, on mouse ascites cells was studied, using the (/sup 125/I)iododeoxyuridine (IUDR) method of labeling the tumor cells. This technique allows a distinction to be made between a cytocidal and cytostatic effect. The 2 drugs exerted a cytocidal effect against 2 non-leukemic cell lines, but had no effect against 3 leukemic lines.

  16. A one-pot radiosynthesis of [125I]iodoazido photoaffinity labels

    International Nuclear Information System (INIS)

    A useful method for preparing radioiodinated photoaffinity labels from alkyl anilines which offer significant advantages over present methods is described. The one-pot synthesis gives good radiochemical yields (40-64%) of pure, high specific activity (350-1500 mCi/?mol) 124I labelled iodaryl azides while minimising manipulation of radioactive materials. Purification of the [125I]iodoazido photoaffinity labels is achieved by high performance liquid chromatography. (author)

  17. A new 125I-anti-DNA-radioimmunoassay for the diagnosis of systematic Lupus erythematosus

    International Nuclear Information System (INIS)

    For a differential diagnosis distinguishing between systematic lupus erythematosus and progressive and chronic polyarthritis, a special RIA method has been developed and tested. The anti-DNA activity was determined as follows: the antigen was a high-molecular double strand DNA from a human tumour cell strain biologically labelled with 125I-desoxyuridine. Free and bound antigen was separated by precipitation using saturated ammonium sulfate solution. Recovery and interassay variance of this RIA are comparable with that of other RIAs. (GSE)

  18. Compartment analysis of 125I-labelled albumin washout from coronary vessels of isolated perfused hearts

    International Nuclear Information System (INIS)

    Albumin labelled with 125I was used as a tracer to investigate the washout kinetics of plasma from the coronary circulation of isolated perfused feline hearts. Compartmentalization with experimental results showed at least two compartments. The model was compared with a three-compartment model found previously for red blood cells. The results indicate that there is a separation of plasma and RBC in the coronary microcirculation. (author)

  19. Autoradiographic localization of beta-adrenoceptors in pig lung using [125I]-iodocyanopindolol.

    OpenAIRE

    Goldie, R G; Papadimitriou, J M; Paterson, J.W.; Rigby, P. J.; Spina, D.

    1986-01-01

    The binding of the beta-adrenoceptor radioligand [125I]-iodocyanopindolol (I-CYP) has been studied in pig lung parenchyma and the distribution of binding sites visualised by light microscopic autoradiography. I-CYP binding was saturable (maximum binding capacity Bmax = 51 +/- 3 fmol mg-1 protein), involving sites with high affinity (dissociation constant KD = 73 +/- 10 pM). Specific I-CYP binding was displaceable both by beta-adrenoceptor agonists ((-)-isoprenaline greater than (-)-adrenaline...

  20. Benzodiazepine effect of 125I-iomazenil-benzodiazepine receptor binding and serum corticosterone level in a rat model

    International Nuclear Information System (INIS)

    To test the change in free or unoccupied benzodiazepine receptor (BZR) density in response to diazepam, we investigated 125I-iomazenil (125I-IMZ) binding and serum corticosterone levels in a rat model. Wistar male rats, which received psychological stress using a communication box for 5 days, were divided into two groups according to the amount of administered diazepam: no diazepam [D (0)] group and 10 mg/kg per day [D (10)] group of 12 rats each. The standardized uptake value (SUV) of 125I-IMZ of the D (10) group were significantly lower (P125I-IMZ, it is clear that diazepam competed with endogenous ligand for the free BZR sites, and the frontal, parietal and temporal cortices, globus pallidus, hippocampus, amygdala and hypothalamus are important areas in which 125I-IMZ binding is strongly affected by administration of diazepam

  1. 125I-iomazenil - benzodiazepine receptor binding and serum corticosterone level during psychological stress in a rat model

    International Nuclear Information System (INIS)

    To test the hypothesis that benzodiazepine receptor density decreases in response to stress, we correlated 125I-iomazenil (125I-IMZ) binding with serum corticosterone levels in a rat model. Wistar male rats were divided into four groups; control group (CON, 10 rats), no physical or psychological stress; and one-, three-, and five-day stress groups of 12 rats each (1-DAY, 3-DAY, and 5-DAY, respectively), receiving psychological stress for the given number of days. Psychological stress were given to rats with a communication box. The standardized uptake value (SUV) of 125I-iomazenil of the 3-DAY and 5-DAY showed that 125I-iomazenil - benzodiazepine receptor binding was significantly reduced in the cortices, accumbens nuclei, amygdala and caudate putamen (p125I-IMZ is a useful radioligand to reflect received stress and its binding in the cortices, accumbens nuclei, amygdala and caudate putamen is strongly affected by psychological stress

  2. Effect of body size on accumulation and distribution of 125I in the green mussel (Perna Viridis)

    International Nuclear Information System (INIS)

    Effect of body size on accumulation and distribution of 125I in the green mussel (Perna Viridis), has been studied. The results showed that concentration capacity of every part in smaller mussels was higher than that in larger ones. Concentration factors of 125I in byssus (about 0.5 x 103?1.5 x 103), the highest in all parts of the mussels, were 30?200 times as that in soft tissues, 200?600 times as that in feet, 600?1000 times as that in shells. Although wet weight of byssus was no more than 1% of whole body's wet weight, the content of 125I accumulated in it accounted for as high as 75% of total 125I content. The relationship between concentration factor of 125I in byssus and whole body's wet weight (or shell length) can be described as a negative power function. (16 refs., 2 figs., 3 tabs.)

  3. Antibody-recognized [125I]estradiol-receptor complex in ovarian epithelial carcinoma

    International Nuclear Information System (INIS)

    Monoclonal antibody against human breast cancer estrogen receptor was used to demonstrate binding of a gamma- and Auger electron-emitting estrogen to the estrogen receptor in ovarian epithelial carcinomas. When cytosols of estrogen receptor-rich ovarian adenocarcinomas were analyzed on sucrose gradients containing 0.4 M KCl, the presence of monoclonal antibody against breast cancer estrogen receptor caused a binding peak for [125I]- and [3H]estradiol to shift from the 4S to the 8-9S region, indicating antibody complex formation with ovarian adenocarcinoma estrogen receptor. The antibody-shifted peak of 8-9S [125I]- and [3H]estradiol binding was totally inhibited by a 100-fold molar excess of diethylstilbestrol (DES), but not by testosterone or progesterone, indicating a preference for estrogen binding by the antibody-shifted estrogen receptor. When estrogen receptor from the nuclear fraction of ovarian adenocarcinomas was incubated with [125I]estradiol at 1C, in the presence of 0.4 M NaSCN to facilitate exchange with endogenous ligand, binding occurred that was inhibitable by DES and restricted to the 4S region. Under these conditions the nuclear estrogen receptor was also shifted to the 8-9S region by the presence of the monoclonal antibody against estrogen receptor

  4. Influence of 125I seed interstitial brachytherapy on recovery of facial nerve function

    International Nuclear Information System (INIS)

    Objective: To study the influence of 125I seed interstitial brachytherapy in parotid region on the recovery of facial nerve function. Methods: A total of the data of 21 patients with primary parotid carcinoma were treated with resection and 125I interstitial brachytherapy. All the patients had no facial palsy before operation and the prescribed dose was 60 Gy. During 4 years of follow-up, the House-Brackmann grading scales and ENoG were used to evaluate the function of facial nerve. According to the modified regional House-Brackmann grading scales, the facial nerve branches of patients in affected side were divided into normal and abnormal groups, and were compared with those in contra-lateral side. Results: Post-operation facial palsy occurred in all the patients, but the facial palsy recovered within 6 months. The latency time differences between affected side and contralateral side were statistically significant in abnormal group from 1 week to 6 months after treatment (t=2.362, P=0.028), and were also different in normal group 1 week after treatment (t=2.522, P=0.027). Conclusions: 125I interstitital brachytherapy has no influence on recovery of facial nerve function after tumor resection and no delayed facial nerve damage. (authors)

  5. Spectroscopic output of {sup 125}I and {sup 103}Pd low dose rate brachytherapy sources

    Energy Technology Data Exchange (ETDEWEB)

    Usher-Moga, Jacqueline; Beach, Stephen M.; DeWerd, Larry A. [Department of Medical Physics, University of Wisconsin--Madison, Madison, Wisconsin 53705 (United States); Global Physics Solutions, St. Joseph, Michigan 49085 (United States); Department of Medical Physics, University of Wisconsin-Madison, Madison, Wisconsin 53705 (United States)

    2009-01-15

    The spectroscopic output of low dose rate (LDR) brachytherapy sources is dependent on the physical design and construction of the source. Characterization of the emitted photons from 12 {sup 125}I and 3 {sup 103}Pd LDR brachytherapy source models is presented. Photon spectra, both along the transverse bisector and at several polar angles, were measured in air with a high-purity reverse electrode germanium (REGe) detector. Measured spectra were corrected to in vacuo conditions via Monte Carlo and analytical methods. The tabulated and plotted spectroscopic data provide a more complete understanding of each source model's output characteristics than can be obtained with other measurement techniques. The variation in fluorescence yield of the {sup 125}I sources containing silver caused greater differences in the emitted spectra and average energies among these seed models than was observed for the {sup 103}Pd sources or the {sup 125}I sources that do not contain silver. Angular spectroscopic data further highlighted the effects of source construction unique to each model, as well as the asymmetric output of many seeds. These data demonstrate the need for the incorporation of such physically measured output characteristics in the Monte Carlo modeling process.

  6. Radioimmunoassay of progesterone in saliva: a simplified technique using 125I-radioligand

    International Nuclear Information System (INIS)

    The value of serial salivary progesterone (P) determinations for evaluation of corpus luteum function compared with sporadic serum samplings is recognized. Salivary P concentrations have previously been determined by a relatively difficult assay which utilizes a tritiated radioligand. The present study was designed to compare this conventional method with a simpler assay utilizing an iodinated radioligand. The values obtained with two different radioimmunoassay (RIA) systems were compared for samples collected throughout the luteal phase of seven normal menstrual cycles and three conception cycles. In the seven nonconception luteal phases as well as in the three conception luteal phases, daily salivary P determinations by the two techniques correlated significantly with each other (r = 0.56; P less than 0.001). For the seven nonconception luteal phases, the salivary P determinations obtained by 125I RIA (Saliva 125I) correlated significantly with the matched serum values (r = 0.54; P less than 0.001). However, the correlation was poor between the salivary P determinations obtained by the 3H RIA (Saliva 3H) and the matched serum values. The simplicity and accuracy of the 125I RIA and the convenience of saliva sampling provide a practical approach to monitor human luteal function

  7. Novel high resolution 125I brachytherapy source dosimetry using Ge-doped optical fibres

    International Nuclear Information System (INIS)

    The steep dose gradients close to brachytherapy sources limit the ability to obtain accurate measurements of dose. Here we use a novel high spatial resolution dosimeter to measure dose around a 125I source and compare against simulations. Ge-doped optical fibres, used as thermoluminescent dosimeters, offer sub-mm spatial resolution, linear response from 10 cGy to >1 kGy and dose-rate independence. For a 125I brachytherapy seed in a PMMA phantom, doses were obtained for source-dosimeter separations from 0.1 cm up to several cm, supported by EGSnrc/DOSRZznrc Monte Carlo simulations and treatment planning system data. The measurements agree with simulations to within 2.3%±0.3% along the transverse and perpendicular axes and within 3.0%±0.5% for measurements investigating anisotropy in angular dose distribution. Measured and Veriseed™ brachytherapy treatment planning system (TPS) values agreed to within 2.7%±0.5%. Ge-doped optical fibre dosimeters allow detailed dose mapping around brachytherapy sources, not least in situations of high dose gradient. - Highlights: • We evaluate fall-off in dose for distances from an 125I source of 1 mm to 60 mm. • The TL of optical fibres accommodate high dose gradients and doses that reduce by a factor of 103 across the range of separations. • We verify measured values using DOSRZnrc Monte Carlo code simulations and the Variseed™ Treatment Planning System. • Measured radial and angular dose are obtained with ?3% uncertainty

  8. Plasma clearance of human 125I-low density lipoproteins (LDL) in copper-deficient rats

    International Nuclear Information System (INIS)

    The rate of plasma removal of human LDL was measured in copper-deficient (CuD), as compared with copper-adequate (CuA) rats. Purified human LDL (d 1.02-1.063) were labeled with 125I. Faster recipient rats were injected via the jugular vein with a dose of 20.6 ?g LDL protein. The 125I radioactivity in 0.2 ml plasma was determined at 1, 2, 4 and 6 hr after dose injection. Percent clearance was calculated based on the plasma volume determined by radioisotope dilution. Mean plasma volumes of CuD and CuA rats were 4.2 and 3.5 ml/100 g bw, respectively. Data showed that LDL were removed at a faster rate in CuD rats. The half-times (t1/2) of LDL in CuD and CuA groups were 4.90 ± 0.20 and 5.80 ± 0.3 hr, respectively. The plasma TCA-soluble 125I radioactivity was significantly and steadily increased in CuD rats at each interval, reflecting the faster removal and degradation of LDL. The findings suggest that the LDL receptor may be up-regulated in CuD rats and that a defective uptake via the receptor is not a cause of the hypercholesterolemia observed in copper deficiency

  9. Synthesis and biological evaluation of 125I-erythropoietin as a potential radiopharmaceutical agent for tumours

    Scientific Electronic Library Online (English)

    Gonçalo dos Santos, Clemente; Vera Lúcia Serra, Duarte.

    2011-03-01

    Full Text Available A eritropoetina (EPO) é um hormônio glicoprotéico responsável pela regulação da eritropoese. Recentemente foi demonstrado que os receptores de EPO (EPOr) estão expressos em algumas linhas celulares neoplásicas, o que sugere a sua potencialidade como um novo alvo terapêutico. Neste trabalho a EPO foi [...] radiomarcada com iodo-125 através do método da lactoperoxidase, menos agressivo para a viabilidade biológica das proteínas. A 125I-EPO revelou ser radioquimicamente estável durante 20 dias após a síntese. Um estudo biológico in vitro em linhas celulares tumorais demonstrou que a 125I-EPO apresenta uma ligação muito fraca ( Abstract in english Erythropoietin (EPO) is a glycoprotein hormone responsible for regulating erythropoiesis. Expression of EPO and EPO receptors (EPOr) has recently been demonstrated in some neoplastic cell lines and tumours, suggesting a potential new target for therapy. In this work, EPO was labeled with iodine-125 [...] using the lactoperoxidase method, known to prevent damage to protein during radioiodination, and labeling conditions were optimized. In vitro stability studies have shown that 125I-EPO is radiochemically stable for 20 days after radiolabeling. In vitro cell binding studies have demonstrated very low binding (

  10. Synthesis and 125I labelling of a precursor for imaging nicotinic acetylcholine receptors

    International Nuclear Information System (INIS)

    Nicotinic Acetylcholine Receptors (nAChRs) are involved in various pharmacological effects or diseases, such as Alzheimer's Disease, Parkinson's Disease and tobacco addiction. It will be very appealing to image nAChRs in vivo, diagnose and treat the above diseases, and probe the mechanism of nAChRs in tobacco addiction if the suitable radioactive labeled compound can be synthesized. In this study, (s)-5-(tri-butylstannyl)-3{[1-(tert-butoxycarbonyl)-2-azetidinyl]methoxy} pyridine, a precursor for imaging nAChRs, was synthesized with commercial 2-furfurylamine and (s)-2-azetidinecarboxylic acid as starting materials, and was further labeled with 125/123I. The whole procedure for radiosynthesis needs 50-55 min and more than 30% of the 125I are found in the purified 5-[125I]-A-85380. Even staying for 3 days at room temperature in vitro, the purified 5-[125I]-I-85380 can maintain its stability, with a radiochemical purity of more than 95%. (authors)

  11. Standardization and decay data determinations of 125I, 54Mn and 203Hg

    International Nuclear Information System (INIS)

    The absolute 4?-?? coincidence counting has been used to measure the activity concentrations of 54Mn and 203Hg, and the Sum-Peak method was used for 125I. 54Mn and 125I radionuclides have been part of international key-comparisons coordinated by the Bureau International des Poids et Measures (BIPM) in 2003/2004, while 203Hg is part of the traceability programme of the National Laboratory for Ionizing Radiation Metrology (LNMRI)/Brazil. Three different detectors were used for the Sum-Peak method: 3''x3'' NaI(Tl) and 5''x5'' well NaI(Tl) scintillation detectors and a planar germanium detector. Direct measurements were made of the photon emission probabilities of the 35.5-, 834.8- and 279.2-keV ?-rays of 125I, 54Mn and 203Hg to give values of (0.0667±0.0014) (0.9997±0.0055) and (0.8161±0.0005), respectively. The half-lives of 203Hg and 54Mn were also determined by means of a 4?? ionization chamber (203Hg) and by the reference source method using a HPGe detector (54Mn) to give values of (46.639±0.023) days and (312.1±0.9) days, respectively

  12. Portable detectors for 125I-insulin absorption measurement during subcutaneous infusion with portable pumps

    International Nuclear Information System (INIS)

    Programmed subcutaneous insulin infusion is a promising method for normalisation of the blood glucose concentration in insulin-dependent diabetics. The absorption rate from the depot is usually measured intermittently by radioactively-labelled insulin and stationary scintillation detectors. Small portable detectors are an alternative, however, and continuous absorption measurements could be made during normal life conditions. Contrary to conventional single injection therapy, the insulin depot initially expands during infusion treatment, changing the geometry during measurements. In the present study the methodological aspects and geometrical dependences were investigated. Simulated studies were made with various plane disc 125I sources in Perspex phantoms as well as 125I-insulin absorption studies in short-term subcutaneous infusion experiments with anaesthetised rabbits. Results from portable, end-window Geiger-Mueller (GM) detectors fixed above the depots and close to the surfaces of phantom or skin were compared with results obtained by a conventional stationary NaI(Tl) detector 15 cm from the phantom or skin surface. With a 125I-insulin infusion site at 5 mm depth in the subcutaneous tissue of rabbits, an overall linear proportionality was found between the results obtained with a NaI(Tl) detector and a GM detector raised 15 mm above the skin surface inside the detector housing. (author)

  13. Pharmacokinetics and tumor retention of 125I-labeled RGD peptide are improved by PEGylation

    International Nuclear Information System (INIS)

    Tumor growth and metastasis are angiogenesis dependent. Overexpression of integrin ?v?3 in angiogenic vessels as well as various malignant human tumors suggests the potential of suitably labeled antagonists of this adhesion receptor for radionuclide imaging and therapy of tumors. Small head-to-tail cyclic peptides including the Arg-Gly-Asp (RGD) amino acid sequence have been radiolabeled and studied in preclinical animal models. However, the fast blood clearance, high kidney and liver uptake, and rapid washout from tumors make this type of tracer ineffective for clinical applications. In this study we modified the cyclic pentapeptide c(RGDyK) with monofunctional methoxy-PEG (mPEG, M.W. = 2,000) and labeled the RGD-mPEG conjugate with 125I. We studied the tumor targeting efficacy and in vivo pharmacokinetic properties of 125I-RGD-mPEG by means of direct tissue sampling and autoradiography in mice xenografted subcutaneously with U87MG glioblastoma. Compared to the 125I-RGD analog, this PEGylated RGD peptide revealed faster blood clearance, lower kidney uptake, and prolonged tumor uptake without compromising the receptor targeting ability

  14. Protein radioiodination in a radioassay laboratory: evaluation of commercial Na125I reagents and related biohazards

    International Nuclear Information System (INIS)

    Three commercial Na125I solutions (Amersham, New England Nuclear, and Union Carbide) have been examined with respect to multiple parameters affecting their use in the radioiodination of three representative peptides (insulin, growth hormone, and gastrin): % of radioiodine incorporation in protein; immunoreactivity and non-specific binding properties of the radiolabeled proteins; pH, volatility, and radionuclidic purity of radioiodine solutions; and vial construction with respect to multidose use. All three commercial Na125I produced radioiodinated proteins of good quality for use in radioligand assays. The radioiodines differed with respect to the amount of iodine released during initial vial opening as a consequence of different pH levels. Two of the three products were shipped in vials with poor construction with respect to multidose use. Selection of a radioiodine was therefore reduced to the secondary considerations of iodine volatility and vial construction. The volatilized radioiodine observed during the spill of millicuries quantities of unbuffered pH 7.5 Na125I was 14 microcuries per millicurie within the first 30 minutes. One thickness of rubber gloves reduced potential skin contamination from an accidental spill to insignificant levels: 20-30 picocuries per microcurie. Common good housekeeping procedures: i.e. rubber gloves, laboratory coat and a fume hood were found to be sufficient protection to eliminate most radioiodine volatility and contamination hazards associated with protein radiolabeling procedures

  15. Direct linkage of 125I-EGF to cell surface receptors: a useful artifact of chloramine-T treatment

    International Nuclear Information System (INIS)

    A study is presented which shows that 125I-EGF that was iodinated by lactoperoxidase treatment bound to cells but did not become linked to EGF receptors. 125I-EGF that was iodinated by chloramine-T treatment or 125I-EGF that was iodinated by lactoperoxidase treatment and then exposed to chloramine-T, formed linked 125I-EGF-receptor complexes. Chloramine-T-treated 125I-EGF remained able to couple to EGF receptors many hours after chloramine-T was removed. These results indicate that chloramine-T ''activates'' 125I-EGF to a new stable form that couples specifically to EGF receptors. This activation did not occur when Tris middle dot Cl was present during the chloramine-T incubation. Because Tris middle dot Cl is nucleophilic and could moderate the oxidizing effects of chloramine-T, this finding suggests that chloramine-T activates EGF as a result of its ability to oxidize certain amino acid residues in proteins. The specific linkage of chloramine-T-treated 125I-EGF to EGF receptors provides a convenient, effective method for radiolabeling EGF receptors. The percentage of human fibroblast EGF receptors cross-linked by 125I-EGF increased to 60% when turnover of EGF receptors at the cell surface was blocked by inhibiting endocytosis with phenylarsine oxide. The linkage of 125I-thrombin to protease-nexin, a cell-released factor that mediates the binding of 125I-thrombin to human fibroblasts, is not a chloramine-T artifact

  16. In vivo binding of /sup 125/I-LSD to serotonin 5-HT/sub 2/ receptors in mouse brain

    Energy Technology Data Exchange (ETDEWEB)

    Hartig, P.R.; Scheffel, U., Frost, J.J.; Wagner, H.N. Jr.

    1985-08-19

    The binding of /sup 125/I-LSD (2-(/sup 125/I)-lysergic acid diethylamide) was studied in various mouse brain regions following intravenous injection of the radioligand. The high specific activity of /sup 125/I-LSD enabled the injection of low mass doses (14ng/kg), which are well below the threshold for induction of any known physiological effect of the probe. The highest levels of /sup 125/I-LSD binding were found in the frontal cortex, olfactory tubercles, extra-frontal cortex and striatum while the lowest level was found in the cerebellum. Binding was saturable in the frontal cortex but increased linearly in the cerebellum with increasing doses of /sup 125/I-LSD. Serotonergic compounds potently inhibited /sup 125/I-LSD binding in cortical regions, olfactory tubercles, and hypothalamus but had no effect in the cerebellum. Dopaminergic compounds caused partial inhibition of binding in the striatum while adrenergic compounds were inactive. From these studies the authors conclude that /sup 125/I-LSD labels serotonin 5-HT/sub 2/ receptor sites in cortical regions with no indication that other receptor sites are labeled. In the olfactory tubercles and hypothalamus, /sup 125/I-LSD labeling occurs predominantly or entirely at serotonic 5-HT/sub 2/ sites. In the striatum, /sup 125/I-LSD labels approximately equal proportions of serotonergic and dopaminergic sites. These data indicate that /sup 125/I-LSD labels serotonin receptors in vivo and suggests that appropriate derivatives of 2I-LSD may prove useful for tomographic imaging of serotonin 5-HT/sub 2/ receptors in the mammalian cortex.

  17. In vivo binding of 125I-LSD to serotonin 5-HT2 receptors in mouse brain

    International Nuclear Information System (INIS)

    The binding of 125I-LSD (2-[125I]-lysergic acid diethylamide) was studied in various mouse brain regions following intravenous injection of the radioligand. The high specific activity of 125I-LSD enabled the injection of low mass doses (14ng/kg), which are well below the threshold for induction of any known physiological effect of the probe. The highest levels of 125I-LSD binding were found in the frontal cortex, olfactory tubercles, extra-frontal cortex and striatum while the lowest level was found in the cerebellum. Binding was saturable in the frontal cortex but increased linearly in the cerebellum with increasing doses of 125I-LSD. Serotonergic compounds potently inhibited 125I-LSD binding in cortical regions, olfactory tubercles, and hypothalamus but had no effect in the cerebellum. Dopaminergic compounds caused partial inhibition of binding in the striatum while adrenergic compounds were inactive. From these studies the authors conclude that 125I-LSD labels serotonin 5-HT2 receptor sites in cortical regions with no indication that other receptor sites are labeled. In the olfactory tubercles and hypothalamus, 125I-LSD labeling occurs predominantly or entirely at serotonic 5-HT2 sites. In the striatum, 125I-LSD labels approximately equal proportions of serotonergic and dopaminergic sites. These data indicate that 125I-LSD labels serotonin receptors in vivo and suggests that appropriate derivatives of 2I-LSD may prove useful for tomographic imaging of serotonin 5-HT2 receptors in the mammalian cortex

  18. Evaluation of iodogen-coated tubes for 125I-iodination of monoclonal antibodies

    International Nuclear Information System (INIS)

    Full text: 125I-iodine labelled antibodies such as anti-CD-20, Rituximab, Mabthera(r): are required for various initial immunoreactivity experiments. For this purpose a progressive method is the usage of IODOGEN precoated iodination tubes. Iodogen has become a wide spread mild and effective solid phase oxidation agent in radiochemistry for the past years. There are different techniques to coat either the reaction vial or the antibody itself, yet for getting acquainted with radioiodination ready to use coated tubes are feasible. Iodogen is a 1,3,4,6-tetrachloro-3?,6?-diphenylglycouril, insoluble in aqueous solutions. Per tube 50?g of this agent are coated inside onto the glass wall of the bottom of the vessel. The labelling procedure is as follows: 0.1 ml antibody - solution (containing l mg MoAb) and 40 to 60 MBq of 125I - NaI in PBS (0.6 m1) are injected through the septum of the tube. After an incubation time of 15 min at room temperature (gently shaking) the reaction is stopped by adding 0.1 ml of a solution of l mg potassium iodide in l ml saline, and simultaneously BioRad AG1-X8, 100-200 mesh, anion exchange resin (20 % in saline). After l min of ion exchange the reaction mixture is passed through a 0.22 ?m membrane filter. Further purification can be obtained by gel filtration through PD-10 columns with PBS as eluent. Radiochernical purity is surveyed by ITLC (0.9 % saline); the 0.5 m1-fractions of the eluate of the gelfiltration are analyzed by ?-scintillation-counting. Overall yields are between 30 and 40 %, yet both yield and reaction velocity are declining with enlarging the reaction volume. The anion exchange resin traps any possible 125I-iodide very well yet the following 0.22 ?m-filtration is consecuted by a retention of up to 23 % of total activity. In the PD-10 purification step the first 2 ml must be discarded whereas the antibody elutes with the next 3 to 4 ml. 125I-Iodide would elute afterwards. The labelling reaction can be performed in the described way very easily yet attention has to be payed to keep the reaction volume as small as possible since otherwise the Na 125I would not get into contact with the iodogen reaction zone at the bottom of the tube. (author)

  19. The biological effect of 125I seed continuous low dose rate irradiation in CL187 cells

    Directory of Open Access Journals (Sweden)

    Zhuang Hong-Qing

    2009-01-01

    Full Text Available Abstract Background To investigate the effectiveness and mechanism of 125I seed continuous low-dose-rate irradiation on colonic cell line CL187 in vitro. Methods The CL187 cell line was exposed to radiation of 60Co? ray at high dose rate of 2 Gy/min and 125I seed at low dose rate of 2.77 cGy/h. Radiation responses to different doses and dose rates were evaluated by colony-forming assay. Under 125I seed low dose rate irradiation, a total of 12 culture dishes were randomly divided into 4 groups: Control group, and 2, 5, and 10 Gy irradiation groups. At 48 h after irradiation, apoptosis was detected by Annexin and Propidium iodide (PI staining. Cell cycle arrests were detected by PI staining. In order to investigate the influence of low dose rate irradiation on the MAPK signal transduction, the expression changes of epidermal growth factor receptor (EGFR and Raf under continuous low dose rate irradiation (CLDR and/or EGFR monoclonal antibodies were determined by indirect immunofluorescence. Results The relative biological effect (RBE for 125I seeds compared with 60Co ? ray was 1.41. Apoptosis rates of CL187 cancer cells were 13.74% ± 1.63%, 32.58% ± 3.61%, and 46.27% ± 3.82% after 2 Gy, 5 Gy, and 10 Gy irradiation, respectively; however, the control group apoptosis rate was 1.67% ± 0.19%. G2/M cell cycle arrests of CL187 cancer cells were 42.59% ± 3.21%, 59.84% ± 4.96%, and 34.61% ± 2.79% after 2 Gy, 5 Gy, and 10 Gy irradiation, respectively; however, the control group apoptosis rate was 26.44% ± 2.53%. P 2/M cell cycle arrest. After low dose rate irradiation, EGFR and Raf expression increased, but when EGFR was blocked by a monoclonal antibody, EGFR and Raf expression did not change. Conclusion 125I seeds resulted in more effective inhibition than 60Co ? ray high dose rate irradiation in CL187 cells. Apoptosis following G2/M cell cycle arrest was the main mechanism of cell-killing effects under low dose rate irradiation. CLDR could influence the proliferation of cells via MAPK signal transduction.

  20. The incidence of radioepidermitis and the dose-response relationship in parotid gland cancer patients treated with 125I seed brachytherapy. Incidence of radioepidermitis and the dose-response relationship

    Energy Technology Data Exchange (ETDEWEB)

    Mao, Ming-Hui; Zheng, Lei; Gao, Hong; Zhang, Jie; Liu, Shu-ming; Huang, Ming-wei; Shi, Yan [Peking University School and Hospital of Stomatology, Department of Oral and Maxillofacial Surgery, Beijing (China); Zhang, Jian-Guo [Peking University School and Hospital of Stomatology, Department of Oral and Maxillofacial Surgery, Beijing (China); Fujian Provincial Hospital, Fujian (China)

    2014-09-09

    We studied the incidence and dose-response relationship of radioepidermitis in parotid gland carcinoma patients treated with [{sup 125}I] seed brachytherapy in the hopes of designing an optimized pre-implant treatment plan that would reduce the incidence and severity of radioepidermitis in patients receiving this therapy. Between January 2007 and May 2010, 100 parotid gland cancer patients were treated postoperatively with [{sup 125}I] seed brachytherapy. The matched peripheral dose (MPD) was 80-140 Gy, and [{sup 125}I] seed activity was 0.7-0.8 mCi. The mean dose delivered to the skin was calculated in the post-implant CT on day 0 following implantation. Grades of acute and late dermatitis were evaluated at 2, 6, 12, and 18 months post-implantation. Most patients experienced grade 0-2 acute and late skin side effects (86 and 97 %, respectively), though a small subset developed severe complications. Most grade 1-3 effects resolved within 6 months of implantation, though some grade 1-3 effects and all grade 4 effects remained unchanged throughout the 18-month follow-up period. Grade 3 and 4 effects were most prominent (75 and 25 %, respectively) with doses of 110-140 Gy; doses higher than 140 Gy produced only grade 4 effects. [{sup 125}I] seed brachytherapy produced acceptable levels of acute and late radioepidermitis with a good clinical outcome. A mean dose under 100 Gy delivered to the skin was safe, though doses of 110-140 Gy should be given with caution and extra monitoring; doses greater than 140 Gy are dangerous and likely to produce grade 4-5 effects. (orig.) [German] Wir untersuchten die Inzidenz und die Dosis-Wirkung-Beziehung bei Patienten mit Ohrspeicheldruesenkrebs, die mit [{sup 125}I]-Seed-Brachytherapie behandelt wurden, in der Hoffnung, eine optimierte praeimplantologische Behandlung zu entwickeln, welche die Inzidenz und Schwere der Radioepidermitis bei Patienten, die diese Therapie erhalten haben, reduziert. Zwischen Januar 2007 und Mai 2010 wurden 100 Patienten mit Ohrspeicheldruesenkrebs postoperativ mit [{sup 125}I]-Seed-Brachytherapie behandelt. Die angeglichene periphere Dosis (MPD) betrug 80-140 Gy und die Aktivitaet der [{sup 125}I]-Seed war 0,7-0,8 mCi. Die durchschnittliche Dosis, die auf die Haut gebracht wurde, wurde beim postimplantologischen CT am Tag 0 nach der Implantation kalkuliert. Die Grade von akuter und verspaeteter Dermatitis wurden nach 2, 6, 12 und 18 Monaten postimplantologisch ausgewertet. Die meisten Patienten erlebten akute und verspaetete Nebenwirkungen (86 % bzw. 97 %) auf der Haut vom Grad 0-2, obwohl eine kleine Untergruppe schwere Komplikationen entwickelte. Die meisten Grad-1- bis Grad-3-Wirkungen hatten sich innerhalb von 6 Monaten nach der Implantation aufgeloest, obwohl einige der Grad-3- bis Grad-4-Wirkungen und alle Grad-4-Wirkungen waehrend des 18-monatigen Nachfolgezeitraums unveraendert geblieben sind. Die Grad-3- bis Grad-4-Wirkungen waren am bedeutendsten (75 % bzw. 25 %) mit der Dosis von 110-140 Gy; eine Dosis hoeher als 140 Gy erzeugte nur Grad-4-Wirkungen. Die [{sup 125}I]-Seed-Brachytherapie erzeugt akzeptable Ebenen von akuter und verspaeteter Radioepidermitis mit einem guten klinischen Ergebnis. Eine durchschnittliche Dosis unter 100 Gy, die auf die Haut aufgebracht wurde, war sicher, obwohl Dosen von 110-140 Gy mit Vorsicht und zusaetzlicher Ueberwachung gegeben werden sollten; Dosen hoeher als 140 Gy sind gefaehrlich und werden wahrscheinlich Grad-4-Wirkungen erzeugen. (orig.)

  1. N-(3-(p-azido-m-[125I]iodophenyl)propionyl)-succinimide--a heterobifunctional reagent for the synthesis of radioactive photoaffinity ligands: synthesis of a carrier-free 125I-labeled cardiac glycoside photoaffinity label

    International Nuclear Information System (INIS)

    A new heterobifunctional reagent, N-(3-(p-azido-m-iodophenyl)propionyl)-succinimide (AIPPS), was synthesized and chemically characterized. The radiochemical form of the reagent, [125I]AIPPS, should be of general use as a photoactive reagent for the derivatization of free amino groups on a large variety of biologically active compounds, including many hormones. Amino-containing ligands can be derivatized with [125I]AIPPS in a method which is similar to that used for the 125I-labeled Bolton-Hunter reagent (N-(3-(p-hydroxyphenyl)propionyl)-succinimide). The added advantage with [125I]AIPPS, however, is that the ligand derivative is made both photoactive and radioactive in a single step. As an example of how this reagent can be used, we have prepared carrier-free [125I]AIPPS and reacted it with the amino-containing cardiac glycoside, 4-amino-4,6-dideoxyglucosyl digitoxigenin (GluD). The radioiodinated cardiac glycoside, [125I]AIPP-GluD, was purified by thin-layer chromatography and was carrier-free with a specific radioactivity of 2175 Ci/mmol. [125I]AIPP-GluD was an effective photoaffinity label for Na,K-ATPase as shown by specific photoaffinity labeling of purified canine kidney enzyme and human erythrocyte enzyme

  2. Dosimetry for 131Cs and 125I seeds in solid water phantom using radiochromic EBT film

    International Nuclear Information System (INIS)

    Purpose: To measure the 2D dose distributions with submillimeter resolution for 131Cs (model CS-1 Rev2) and 125I (model 6711) seeds in a Solid Water phantom using radiochromic EBT film for radial distances from 0.06 cm to 5 cm. To determine the TG-43 dosimetry parameters in water by applying Solid Water to liquid water correction factors generated from Monte Carlo simulations. Methods: Each film piece was positioned horizontally above and in close contact with a 131Cs or 125I seed oriented horizontally in a machined groove at the center of a Solid Water phantom, one film at a time. A total of 74 and 50 films were exposed to the 131Cs and 125I seeds, respectively. Different film sizes were utilized to gather data in different distance ranges. The exposure time varied according to the seed air-kerma strength and film size in order to deliver doses in the range covered by the film calibration curve. Small films were exposed for shorter times to assess the near field, while larger films were exposed for longer times in order to assess the far field. For calibration, films were exposed to either 40 kV (M40) or 50 kV (M50) x-rays in air at 100.0 cm SSD with doses ranging from 0.2 Gy to 40 Gy. All experimental, calibration and background films were scanned at a 0.02 cm pixel resolution using a CCD camera-based microdensitometer with a green light source. Data acquisition and scanner uniformity correction were achieved with Microd3 software. Data analysis was performed using ImageJ, FV, IDL and Excel software packages. 2D dose distributions were based on the calibration curve established for 50 kV x-rays. The Solid Water to liquid water medium correction was calculated using the MCNP5 Monte Carlo code. Subsequently, the TG-43 dosimetry parameters in liquid water medium were determined. Results: Values for the dose-rate constants using EBT film were 1.069±0.036 and 0.923±0.031 cGy U?1 h?1 for 131Cs and 125I seed, respectively. The corresponding values determined using the Monte Carlo method were 1.053±0.014 and 0.924±0.016 cGy U?1 h?1 for 131Cs and 125I seed, respectively. The radial dose functions obtained with EBT film measurements and Monte Carlo simulations were plotted for radial distances up to 5 cm, and agreed within the uncertainty of the two methods. The 2D anisotropy functions obtained with both methods also agreed within their uncertainties. Conclusion: EBT film dosimetry in a Solid Water phantom is a viable method for measuring 131Cs (model CS-1 Rev2) and 125I (model 6711) brachytherapy seed dose distributions with submillimeter resolution. With the Solid Water to liquid water correction factors generated from Monte Carlo simulations, the measured TG-43 dosimetry parameters in liquid water for these two seed models were found to be in good agreement with those in the literature. - Highlights: • Measure the 2D dose distributions for 131Cs and 125I seeds using radiochromic film. • For distances (0.06–5 cm) with submillimeter resolution in a Solid Water phantom. • Generate Solid Water to liquid water correction factors from Monte Carlo simulations. • Determine the TG-43 dosimetry parameters in water by applying the correction factors

  3. Development of virtual patient models for permanent implant brachytherapy Monte Carlo dose calculations: interdependence of CT image artifact mitigation and tissue assignment

    Science.gov (United States)

    Miksys, N.; Xu, C.; Beaulieu, L.; Thomson, R. M.

    2015-08-01

    This work investigates and compares CT image metallic artifact reduction (MAR) methods and tissue assignment schemes (TAS) for the development of virtual patient models for permanent implant brachytherapy Monte Carlo (MC) dose calculations. Four MAR techniques are investigated to mitigate seed artifacts from post-implant CT images of a homogeneous phantom and eight prostate patients: a raw sinogram approach using the original CT scanner data and three methods (simple threshold replacement (STR), 3D median filter, and virtual sinogram) requiring only the reconstructed CT image. Virtual patient models are developed using six TAS ranging from the AAPM-ESTRO-ABG TG-186 basic approach of assigning uniform density tissues (resulting in a model not dependent on MAR) to more complex models assigning prostate, calcification, and mixtures of prostate and calcification using CT-derived densities. The EGSnrc user-code BrachyDose is employed to calculate dose distributions. All four MAR methods eliminate bright seed spot artifacts, and the image-based methods provide comparable mitigation of artifacts compared with the raw sinogram approach. However, each MAR technique has limitations: STR is unable to mitigate low CT number artifacts, the median filter blurs the image which challenges the preservation of tissue heterogeneities, and both sinogram approaches introduce new streaks. Large local dose differences are generally due to differences in voxel tissue-type rather than mass density. The largest differences in target dose metrics (D90, V100, V150), over 50% lower compared to the other models, are when uncorrected CT images are used with TAS that consider calcifications. Metrics found using models which include calcifications are generally a few percent lower than prostate-only models. Generally, metrics from any MAR method and any TAS which considers calcifications agree within 6%. Overall, the studied MAR methods and TAS show promise for further retrospective MC dose calculation studies for various permanent implant brachytherapy treatments.

  4. Comparison of 3H-TdR and 125I-UdR incorporation on the proliferation effect of lymphocytes

    International Nuclear Information System (INIS)

    Objective: To compare the incorporation method of 3H-TdR and 125I-UdR on determining the proliferation effect of lymphocytes. Methods: The proliferation effects of lymphocyte and Daudi lymphoma cells were estimated by 3H-TdR and 125I-UdR incorporation. Results: The incorporating fraction of 3H-TdR and 125I-UdR into lymphocyte was 20.95% ± 1.06% and 1.00% ±0.04%,respectively, and the incorporating fraction for the lymphoma cells was 29. 94% ± 4. 10% and 6. 02% ±0. 73% ,respectively. The incorporation fractions of 3H-TdR into lymphocyte and lymphoma cells were much higher than those of 125I-UdR, but the incorporating fractions of 3H-TdR or 125I-UdR into the lymphoma cells were much higher than those of lymphocytes. Conclusions: For lymphocytes, 125I-UdR cannot substitute 3H-TdR as a tracer agent. But for lymphoma cells, whether 125I-UdR could be replace 3H-TdR or not needs further research. (authors)

  5. The preliminary biocharacteristic study of a potential dopamine D3 receptor imaging agent, 125I-7-OH-PIPAT

    International Nuclear Information System (INIS)

    Objective: To study the biocharacteristics of a potential dopamine D3 receptor imaging agent, 125I-7-hydroxy-2-[N-propyl-N-(3'-iodo-2'-propenyl)-amino]tetralin (7-OH-PIPAT) which was synthesized in this lab. Methods: 125I-7-OH-PIPAT was used as a radioactive tracer to study the biodistribution of 125I-7-OH-PIPAT in rats and in particular, in the brain regions, and autoradiography was used to study the binding sites of 125I-7-OH-PIPAT in rat brain slices. Results: The uptake of 125I-7-OH-PIPAT in the whole brain reached to 1%, and autoradiography showed that 125I-7-OH-PIPAT was accumulated at olfactory tubercle and limbic regions of rat brain. Conclusions: 125I-7-OH-PIPAT is able to penetrate the brain blood barrier, and has the affinity to dopamine D3 receptors. It has the potential activity to be a dopamine D3 receptor imaging agent

  6. 125I-human epidermal growth factor specific binding to placentas and fetal membranes from varoius pregnancy states

    International Nuclear Information System (INIS)

    Specific binding of 125I-human epidermal growth factor (hEGF) to homogenates of term human placentas and fetal membranes from normal and appropriate for gestational age (N = 20), intrauterine growth retarded (N = 9), twin (N = 11), White class A/B diabetic (N = 12), and large for gestational age (N = 13) pregnancies was measured. In all pregnancy states, placentas bound approximately four times more 125I-hEGF than did fetal membranes (P125I-hEGF binding to fetal membranes from the various pregnancy states (P125I-hEGF specific binding to placentas from intrauterine growth retarded or twin pregnancies was significantly greater compared with placentas from normal and appropriate for gestational age pregnancies (P125I-hEGF specific binding did not differ between placentas from intrauterine growth retarded or twin pregnancies (P125I-hEGF binding did not vary with fetal sex, maternal race, placental weight, or gestational age between 37 to 42 weeks (P125I-hEGF binding increased with increasing infant weight when appropriate for gestational age and large for gestational age infants were included (P<0.05, r = 0.38, N = 32) but not for intrauterine growth retarded, appropriate for gestational age, or large for gestational age infants alone. (author)

  7. Specific cytotoxicity of 16 alpha-[125I]iodoestradiol for estrogen receptor-containing breast cancer cells

    International Nuclear Information System (INIS)

    We attempted to induce specific killing of estrogen receptor-containing breast cancer cells using estradiol coupled to a high specific activity gamma emitting isotope of iodine. MCF-7 human breast cancer cells were incubated with 16 alpha-[125I]iodoestradiol alone ([125I]E2), or with 16 alpha-[125I]iodoestradiol plus 100-fold excess 17 beta-estradiol (E2), and then viably frozen. After 8 weeks, the [125I]E2 exposed cells and the [125I]E2 plus E2 exposed cells were 10% and 77% of controls, respectively. When the breast cancer cell line MDA-MB-231 which does not contain estrogen receptors was used, the rate of cell death was similar to the competed MCF-7 cells. When specific cytotoxicity was compared using a cloning technique, nearly a 5 log reduction in surviving cell fraction was seen with [125I]E2, as compared to identical cells treated with [125I]E2 plus competitor. This technique shows promise for selecting a population of cells with defects in their estrogen receptor and in studying subcellular hormone interactions

  8. 125I-labeled protein A as a general tracer in immunoassay: suitability of goat and sheep antibodies

    International Nuclear Information System (INIS)

    The immunoassay method in which 125<