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Sample records for 125i permanent implant

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

    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)

  2. Evaluation of prostate coverage and calculation of TCP in permanent prostatic implants with 125I rapid strands

    Localized prostate cancer can be treated by a permanent implant with 125I seeds. A major advantage of a permanent implant is the small planning target volume, which has to be significantly larger in external beam irradiation to accommodate for the less steep dose gradient, uncertainties in patient set up and for prostate movement. The aim of this work is to evaluate prostate coverage in permanent implants with 125I RAPID strands and to compare tumor control probability (TCP) achievable by external beam radiotherapy and by permanent implants

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

    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)

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

    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

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

    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)

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

    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

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

    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)

  8. Edema-induced increase in tumour cell survival for 125I and 103Pd prostate permanent seed implants - a bio-mathematical model

    Yue, Ning; Chen, Zhe; Nath, Ravinder

    2002-04-01

    Edema caused by the surgical procedure of prostate seed implantation expands the source-to-point distances within the prostate and hence decreases the dose coverage. The decrease of dose coverage results in an increase in tumour cell survival. To investigate the effects of edema on tumour cell survival, a bio-mathematical model of edema and the corresponding cell killing by continuous low dose rate irradiation (CLDRI) was developed so that tumour cell surviving fractions can be estimated in an edematous prostate for both 125I and 103Pd seed implants. The dynamic nature of edema and its resolution were modelled with an exponential function V(T) = Vp (1 + M exp(-0.693T/Te)) where Vp is the prostate volume before implantation, M is the edema magnitude and Te is edema half-life (EHL). The dose rate of a radioactive seed was calculated according to AAPM TG43, i.e. Λg(r) αBED), where α is the linear coefficient of the survival curve. The tumour cell survival was calculated for both 125I and 103Pd seed implants and for different tumour potential doubling time (TPDT) (from 5 days to 30 days) and for edemas of different magnitudes (from 0% to 95%) and edema half-lives (from 4 days to 30 days). Tumour cell survival increased with the increase of edema magnitude and EHL. For a typical edema of a half-life of 10 days and a magnitude of 50%, the edema increased tumour cell survival by about 1 and 2 orders of magnitude for 125I and 103Pd seed implants respectively. At the extreme (95% edema magnitude and an edema half-life of 30 days), the increase was more than 3 and 5 orders of magnitude for 125I and 103Pd seed implants respectively. The absolute increases were almost independent of TPDT and the prostate edema did not significantly change the effective treatment time. Tumour cell survival for prostate undergoing CLDRI using 125I or 103Pd seeds may be increased substantially due to the presence of edema caused by surgical trauma. This effect appears to be more pronounced for 103Pd than 125I because of the shorter half-life of 103Pd. If significant edema is observed post implantation, then a boost to the prostate using external beam radiotherapy may be considered as a part of the treatment strategy.

  9. Edema-induced increase in tumour cell survival for 125I and 103Pd prostate permanent seed implants - a bio-mathematical model

    Edema caused by the surgical procedure of prostate seed implantation expands the source-to-point distances within the prostate and hence decreases the dose coverage. The decrease of dose coverage results in an increase in tumour cell survival. To investigate the effects of edema on tumour cell survival, a bio-mathematical model of edema and the corresponding cell killing by continuous low dose rate irradiation (CLDRI) was developed so that tumour cell surviving fractions can be estimated in an edematous prostate for both 125I and 103Pd seed implants. The dynamic nature of edema and its resolution were modelled with an exponential function V(T)=Vp (1+M exp(-0.693T/Te)) where Vp is the prostate volume before implantation, M is the edema magnitude and Te is edema half-life (EHL). The dose rate of a radioactive seed was calculated according to AAPM TG43, i.e. D radical SkΔg(r) φ-baran/r2, where r is the distance between a seed and a given point. The distance r is now a function of time because of edema. The g(r) was approximated as 1/r0.4 and 1/r0.8 for 125I and 103Pd, respectively. By expanding the mathematical expression of the resultant dose rate in a Taylor series of exponential functions of time, the dose rate was made equivalent to that produced from multiple fictitious radionuclides of different decay constants and strengths. The biologically effective dose (BED) for an edematous prostate implant was then calculated using a generalized Dale equation. The cell surviving fraction was computed as exp(-αBED), where α is the linear coefficient of the survival curve. The tumour cell survival was calculated for both 125I and 103Pd seed implants and for different tumour potential doubling time (TPDT) (from 5 days to 30 days) and for edemas of different magnitudes (from 0% to 95%) and edema half-lives (from 4 days to 30 days). Tumour cell survival increased with the increase of edema magnitude and EHL. For a typical edema of a half-life of 10 days and a magnitude of 50%, the edema increased tumour cell survival by about 1 and 2 orders of magnitude for 125I and 103Pd seed implants respectively. At the extreme (95% edema magnitude and an edema half-life of 30 days), the increase was more than 3 and 5 orders of magnitude for 125I and 103Pd seed implants respectively. The absolute increases were almost independent of TPDT and the prostate edema did not significantly change the effective treatment time. Tumour cell survival for prostate undergoing CLDRI using 125I or 103Pd seeds may be increased substantially due to the presence of edema caused by surgical trauma. This effect appears to be more pronounced for 103Pd than 125I because of the shorter half-life of 103Pd. If significant edema is observed post implantation, then a boost to the prostate using external beam radiotherapy may be considered as a part of the treatment strategy. (author)

  10. Edema-induced increase in tumour cell survival for {sup 125}I and {sup 103}Pd prostate permanent seed implants - a bio-mathematical model

    Yue Ning; Chen Zhe; Nath, Ravinder [Department of Therapeutic Radiology, Yale University School of Medicine, New Haven, CT (United States)

    2002-04-01

    Edema caused by the surgical procedure of prostate seed implantation expands the source-to-point distances within the prostate and hence decreases the dose coverage. The decrease of dose coverage results in an increase in tumour cell survival. To investigate the effects of edema on tumour cell survival, a bio-mathematical model of edema and the corresponding cell killing by continuous low dose rate irradiation (CLDRI) was developed so that tumour cell surviving fractions can be estimated in an edematous prostate for both {sup 125}I and {sup 103}Pd seed implants. The dynamic nature of edema and its resolution were modelled with an exponential function V(T)=V{sub p} (1+M exp(-0.693T/T{sub e})) where V{sub p} is the prostate volume before implantation, M is the edema magnitude and T{sub e} is edema half-life (EHL). The dose rate of a radioactive seed was calculated according to AAPM TG43, i.e. D radical S{sub k}{delta}g(r) {phi}-bar{sub an}/r{sup 2}, where r is the distance between a seed and a given point. The distance r is now a function of time because of edema. The g(r) was approximated as 1/r{sup 0.4} and 1/r{sup 0.8} for {sup 125}I and {sup 103}Pd, respectively. By expanding the mathematical expression of the resultant dose rate in a Taylor series of exponential functions of time, the dose rate was made equivalent to that produced from multiple fictitious radionuclides of different decay constants and strengths. The biologically effective dose (BED) for an edematous prostate implant was then calculated using a generalized Dale equation. The cell surviving fraction was computed as exp(-{alpha}BED), where {alpha} is the linear coefficient of the survival curve. The tumour cell survival was calculated for both {sup 125}I and {sup 103}Pd seed implants and for different tumour potential doubling time (TPDT) (from 5 days to 30 days) and for edemas of different magnitudes (from 0% to 95%) and edema half-lives (from 4 days to 30 days). Tumour cell survival increased with the increase of edema magnitude and EHL. For a typical edema of a half-life of 10 days and a magnitude of 50%, the edema increased tumour cell survival by about 1 and 2 orders of magnitude for {sup 125}I and {sup 103}Pd seed implants respectively. At the extreme (95% edema magnitude and an edema half-life of 30 days), the increase was more than 3 and 5 orders of magnitude for {sup 125}I and {sup 103}Pd seed implants respectively. The absolute increases were almost independent of TPDT and the prostate edema did not significantly change the effective treatment time. Tumour cell survival for prostate undergoing CLDRI using {sup 125}I or {sup 103}Pd seeds may be increased substantially due to the presence of edema caused by surgical trauma. This effect appears to be more pronounced for {sup 103}Pd than {sup 125}I because of the shorter half-life of {sup 103}Pd. If significant edema is observed post implantation, then a boost to the prostate using external beam radiotherapy may be considered as a part of the treatment strategy. (author)

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

    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. 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

    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

  13. Customized planning for radioactive 125I seed implantation

    Objective: To customize the optimal plans for radioactive 125I seeds volumetric implants in selected regular target volumes. Methods: 125I seeds were symmetrically and uniformly implanted into 3 spherical targets with the diameters of 1, 2 and 3 cm and 7 ellipsoidal targets with the 3 dimensions of 1 cm×1 cm×2 cm, 1 cm×1 cm×3 cm, 1 cm×2 cm×2 cm, 1 cm×2 cm×3 cm, 1 cm ×3 cm ×3 cm, 2 cm×2 cm×3 cm and 2 cm×3 cm×3 cm. The activity and inter-space of seeds were adjusted to obtain the conformal and uniform dose distribution, with the prescribed D90 (the dose delivered to 90% of the targets) greater than 145 Gy. The inter-space of seeds was changed from 1 cm to 0.75 cm, to improve the conformity and uniformity of dose distribution. Plan quality was assessed using homogeneity index (HI), external index (EI) and conformal index (CI). The activity and number of seeds implanted were also recorded and compared. Results: For the spherical target with the diameter of 1 cm, when seeds were implanted with the inter-space of 1 cm and 0.75 cm, the HI were 40.0% and 55.9%, the EI were 98.3% and 95.1%, the CI were 0.44 and 0.44, respectively. For the spherical target with the diameter of 3 cm and the target with the 3 dimensions of 1 cm × 2 cm × 2 cm, the implant with the inter-space of 1 cm provided better indices of HI, EI and CI than those with the inter-space of 0.75 cm. For the other targets, the implants with the inter-space of 0.75 cm provided better indices of EI and CI than those with the inter-space of 1 cm, although they displayed a little worse homogeneity in terms of HI. The activity per seed was 17.0-27.8 MBq and 30.0-58.8 MBq in the implants with the inter-spaces of 0.75 cm and 1 cm, respectively. 2-10 more seeds were needed in the implants with the inter-space of 0.75 cm. Conclusions: For the studied targets except the spherical targets with the diameter of 1 cm and 3 cm and the ellipsoidal target with the dimension of 1 cm × 2 cm × 2 cm, 125I seeds implanted with the inter-space of 0.75 cm could provide more conformal dose distribution. It could be the better customized plans for uniformly spaced seed implantation. (authors)

  14. Ejaculatory Function After Permanent 125I Prostate Brachytherapy for Localized Prostate Cancer

    Purpose: Ejaculatory function is an underreported aspect of male sexuality in men treated for prostate cancer. We conducted the first detailed analysis of ejaculatory function in patients treated with permanent 125I prostate brachytherapy for localized prostate cancer. Patients and Methods: Of 270 sexually active men with localized prostate cancer treated with permanent 125I prostate brachytherapy, 241 (89%), with a mean age of 65 years (range, 43-80), responded to a mailed questionnaire derived from the Male Sexual Health Questionnaire regarding ejaculatory function. Five aspects of ejaculatory function were examined: frequency, volume, dry ejaculation, pleasure, and pain. Results: Of the 241 sexually active men, 81.3% had conserved ejaculatory function after prostate brachytherapy; however, the number of patients with rare/absent ejaculatory function was double the pretreatment number (p < .0001). The latter finding was correlated with age (p < .001) and the preimplant International Index of Erectile Function score (p < .001). However, 84.9% of patients with maintained ejaculatory function after implantation reported a reduced volume of ejaculate compared with 26.9% before (p < .001), with dry ejaculation accounting for 18.7% of these cases. After treatment, 30.3% of the patients experienced painful ejaculation compared with 12.9% before (p = .0001), and this was associated with a greater number of implanted needles (p = .021) and the existence of painful ejaculation before implantation (p < .0001). After implantation, 10% of patients who continued to be sexually active experienced no orgasm compared with only 1% before treatment. in addition, more patients experienced late/difficult or weak orgasms (p = .001). Conclusion: Most men treated with brachytherapy have conserved ejaculatory function after prostate brachytherapy. However, most of these men experience a reduction in volume and a deterioration in orgasm.

  15. Dosimetric effect of tissue heterogeneity for 125I prostate implants

    Oliveira, Susana Maria; Teixeira, Nuno José; Fernandes, Lisete; Teles, Pedro; Vaz, Pedro

    2014-01-01

    Aim To use Monte Carlo (MC) together with voxel phantoms to analyze the tissue heterogeneity effect in the dose distributions and equivalent uniform dose (EUD) for 125I prostate implants. Background Dose distribution calculations in low dose-rate brachytherapy are based on the dose deposition around a single source in a water phantom. This formalism does not take into account tissue heterogeneities, interseed attenuation, or finite patient dimensions effects. Tissue composition is especially important due to the photoelectric effect. Materials and methods The computed tomographies (CT) of two patients with prostate cancer were used to create voxel phantoms for the MC simulations. An elemental composition and density were assigned to each structure. Densities of the prostate, vesicles, rectum and bladder were determined through the CT electronic densities of 100 patients. The same simulations were performed considering the same phantom as pure water. Results were compared via dose–volume histograms and EUD for the prostate and rectum. Results The mean absorbed doses presented deviations of 3.3–4.0% for the prostate and of 2.3–4.9% for the rectum, when comparing calculations in water with calculations in the heterogeneous phantom. In the calculations in water, the prostate D90 was overestimated by 2.8–3.9% and the rectum D0.1cc resulted in dose differences of 6–8%. The EUD resulted in an overestimation of 3.5–3.7% for the prostate and of 7.7–8.3% for the rectum. Conclusions The deposited dose was consistently overestimated for the simulation in water. In order to increase the accuracy in the determination of dose distributions, especially around the rectum, the introduction of the model-based algorithms is recommended. PMID:25337412

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

    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

    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.

    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

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

    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

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

    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

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

    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)

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

    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 (χ2=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)

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

    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)

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

    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

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

    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)

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

    To evaluate predictive factors for PSA bounce after 125I permanent seed prostate brachytherapy and identify criteria that distinguish between benign bounces and biochemical relapses. 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. 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 < 0.0001). 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

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

    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.

  8. 125I seed implant brachytherapy for the treatment of parotid gland cancers in children and adolescents

    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.)

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

    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)

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

    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 4.5cm. 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 230 months, and median time was 16months. Symptoms of refractory pain were significantly resolved postimplantation (P<0.05), and Karnofsky score rose dramatically (P<0.05). Most patients reported pain relief 25days after treatment. Follow-up imaging studies were performed 2months 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 25.5months. Seven patients died of recurrent tumor; 16 patients died of multiorgan failure or other metastases. Two patients survived after 30months follow-up. Two patients reported localized skin erythema 1week 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.

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

    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.

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

    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)

  13. CT-guided 125I radioactive seed implantation for locally recurrent rectal cancer

    Objective: To evaluate the efficacy and adverse reactions of CT-guided 125I radioactive seed implantation in treatment of locally recurrent rectal cancer (LRRC). Methods: Thirty patients with LRRC who refused operation or were unable to endure pelvic radiotherapy received 125I seed implantation under CT guidance. Three-dimensional treatment planning system was used to calculate the number, activity, and dose of the seeds needed. The activity of seeds ranged from 14.8 to 29.6 MBq with a median of 25.9 MBq, the seed numbers ranged from 33 to 137 with a median of 74.5, the prescription doses ranged from 120-160 Gy,and the actual verification dose D90 ranged from 75.91 to 159.32 Gy with a median of 119.77 Gy. Dosimetric verification by CT scanning was conducted immediately after the treatment. Follow-up was conducted for 15.2 months(4.2-35.0 months). Results: The follow-up rate was 93.3%. The pain relief rate was 95.2%. The overall response rate was 50.0%, including a complete response rate of 13.3% and a partial response rate of 36.7%. The 1- and 2-year local control rates were 30.0% and 8.0% respectively. The median local control survival time was 7.8 month. The 1- and 2-year survival rates were 66.5% and 32.9% respectively. The median overall survival time was 21.5 months. Complications, mainly adverse effects of skin and urinary system (frequent urination, urgent urination, and dysuria) occurred in 6 patients with a rate of 20.0%. Conclusions: Minimally invasive and with satisfying efficacy and tolerable complications, CT-guided 125I radioactive seed implantation is a favorable option for treatment of LRRC, especially for the patients who have undergone previous pelvic radiation. (authors)

  14. The effectiveness and safety of 125I seed implantation for treatment of gastric cancer

    Objective: To explore the effectiveness of 125I seed implantation for gastric cancer and to determine whether the therapy could increase the survival rate. Methods: Seventy-six gastric cancer patients in stage Ⅱ or Ⅲ were involved and randomly divided into treatment group (n=42) and control group (n=34) by simple random sampling method. The patients in the control group underwent D2 or D3 surgery and the patients in treatment group underwent D2 or D3 surgery plus interstitial implantation of 125I seeds. All patients signed the informed consents. Treatment results were evaluated as CR, PR, NC and PD. CR and PR were considered as effective and the effective rate was calculated. All patients were followed up and the three-or five-year survival rate was calculated, the complications were examined. χ2 test was used to compare the significant difference between the two groups. Results: The total effective rate in control group was 50.00% (17/34), lower than that of treatment group (73.81%, 31/42; χ2=4.578, P<0.05). In the treatment group, the three-year and five-year survival rates were 61.90% (26/42) and 42.86% (18/42) respectively, and the corresponding rates in the control group were 11.76%(4/34) and 0(0/34) respectively (χ2=19.771, 19.094, both P<0.001). Both of the two groups had few severe side effects. Conclusion: Radical surgery plus 125I seed implantation is effective and safe for the treatment of stage Ⅱ or Ⅲ gastric cancer and can further improve long-term survival. (authors)

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

    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)

  16. Optimum timing for image-based dose evaluation of 125I and 103Pd prostate seed implants

    Purpose/Objective: Image-based dose evaluation of permanent brachytherapy implants for prostate cancer is important for optimal patient management after implantation. Because of edema caused by the surgical procedure in the implantation, if the dose evaluation is based on the images obtained too early after implantation, dose coverage will usually be underestimated. Conversely, if the images are obtained too late, the dose coverage will be overestimated. This study uses a biomathematical model to simulate edema and its resolution on 29 patients, so that the optimum time to obtain image scans and perform dose evaluation can be investigated and estimated. Methods and Materials: Edema of a prostate and its resolution has been shown to follow an exponential function V(t) = V(0)(1 + ΔV[e-0.693t/Te- 1]) where ΔV is the initial relative increase in the prostate volume due to edema (and is related to edema magnitude), and Te (edema half-life) is the time for the edema to decrease by half in volume. In this study, edema was simulated by increasing the volume of preimplant prostate (obtained from ultrasound volume study) to a given magnitude of edema. Similarly, the locations of planned seeds were changed to their corresponding locations in the edematous prostate proportionally. The edema was then allowed to resolve according to the exponential function. The correct dose distribution was calculated by taking into account the dynamic variations of the prostate volume, seed locations, and source strengths with respect to time. Dose volume histograms (DVHs) were then generated from this dose distribution. The conventional postimplant DVHs, which assume the prostate volume and seed locations are as in the image scans and constant in time, were also calculated based on the simulated image scans for various days postimplantation. The conventional DVHs of prostate on various days after implantation were compared to the DVH calculated assuming dynamic conditions. The optimum timing for conventional postimplant dose evaluation was identified as the time at which a minimum difference between the conventional DVH and the dynamic model DVH was achieved. The analysis was done on 29 prostate seed implant patients for both 125I and 103Pd. The edema magnitude was assumed to be 30%, 40%, 50%, 75%, and 100% of original prostate volume, and the half-life of edema was assumed to be 4, 7, 10, 15, 20, and 25 days. In this study, the original volume of prostate varied from 17 cm3 to 91 cm3, and number of seeds in the implants varied from 57 to 119. Results: The optimum timing was mainly dependent on the half-lives of edema and radionuclides, and varied slightly with edema magnitude, prostate volume, and number of seeds. It can be expressed as a function of edema half-life in the form of C0+ C1exp(-C2Te). However, if the dose evaluation was performed based on the image scans taken too early or too late, the error became larger, as the edema magnitude was larger. By averaging all 29 patients and various edemas, it was found that for 125I seed implants, if the postimplant dose evaluation is performed based on image scans taken between 5 and 9 weeks, the average error will be less than 5%, with a maximum possible error less than 10% in 80% coverage dose; for 103Pd seed implants, if the postimplant dose evaluation is performed based on image scans taken between 2 and 4 weeks, the average error will be less than 5%, with a maximum error less than 15% in 80% coverage dose. Because of edema, a conventional preimplant plan also overestimates dose coverage of prostate. On the average, a standard preimplant planning overestimates dose coverage by about 6% for 125I implants and 14% for 103Pd implants in our study. Conclusion: Based on the dynamic model, the optimum timing of image scans for postimplant dose evaluation of prostate seed implantation is 7 weeks postimplantation for 125I implants and about 3 weeks for 103Pd implants. The time-window for reasonable accuracy (± 5%) is ± 2 weeks for 125I a nd ± 1 week for 103Pd around the optimum timing. During preimplant procedure, the minimum prescribed coverage dose should be increased by an amount of about 6% for 125I implants and about 14% for 103Pd implants to compensate for the effect of edema

  17. Clinical application of CT-guided 125I seed interstitial implantation for local recurrent rectal carcinoma

    Chen Kemin

    2011-10-01

    Full Text Available Abstract Purpose The present study aimed to explore the safety profile and clinical efficacy of CT-guided radioactive seed implantation in treating local recurrent rectal carcinoma. Materials and methods CT-guided 125I seed implantation was carried out in 20 patients with locally recurrent rectal carcinoma. 14 of the 20 patient had prior adjuvant external-beam radiation therapy (EBRT. The treatment planning system (TPS was used preoperatively to reconstruct three dimensional images of the tumor and to calculate the estimated seed number and distribution. The median matched peripheral dose (MPD was 120 Gy (range, 100-160 Gy. Results Of the 20 patients, 12 were male, 8 were female, and ages ranged from 38 to 78, with a median age of 62. Duration of follow-up was 3-34 months. The response rate of pain relief was 85% (17/20. Repeat CT scan 2 months following the procedure revealed complete response (CR of the tumor in 2 patients, partial response (PR in 13 patients, stable disease (SD in 3 patients, and progressive disease (PD in 2 patients. 75% of patients had either CR or PR. Median survival time was 18.8 months (95% CI: 3.5-22.4 months. 1 and 2 year survival rates were 75% and 25%, respectively. 4 patients died of recurrent tumor; 4 patients died of distant metastases; 9 patients died of recurrent tumor and distant metastases. 3 patients survived after 2 year follow up. Two patients were found to have mild hematochezia, which was reversible with symptomatic management. Conclusion CT-guided 125I seed implantation appeared to be a safe, useful and less complicated interventional treatment option for local recurrent rectal carcinoma.

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

    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

    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

    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 (χ2=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; χ2=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

    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

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

    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)

  4. 125I implantation combined with chemotherapy for treatment of local recurrent stage Ⅲ non-small cell lung cancer

    Objective: To investigate the associated effect of 125I implantation plus chemotherapy in local recurrent stage Ⅲ NSCLC patients. Methods: From January 2006 to January 2009, 34 patients documented with local recurrent stage Ⅲ 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 (χ2=8.40,P<0.01), the median of PFS time (χ2=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 Ⅲ NSCLC patients is safe and effective, and its efficacy is superior to the second line chemotherapy alone. (authors)

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

    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,θ) 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)

  6. Implantation of 125I seeds for the treatment of non-small cell lung cancer: evaluation of short-term effect

    Objective: To assess the short-term effect, feasibility and safety of 125I seeds implantation in treating non-small cell lung cancer. Methods: During the period from June 2010 to December 2012 a total of 353 patients with lung cancer were admitted to authors' hospital, of whom 56 met the study standards. The 56 cases were divided into study group (n=24) and control group (n=32). Bronchial artery chemotherapy with subsequent 125I seeds implantation was carried out in the patients of study group, while only bronchial artery chemotherapy was performed in the patients of control group. The median survival time was compared between the two groups. Results: The median survival time of the study group and the control group was (22.8±1.9) months and (14.2±1.3) months respectively. The median survival time of the study group was significantly higher than that of the control group (P=0.006). Conclusion: Compared with simple bronchial artery chemotherapy, permanent implantation of 125I seeds combined with bronchial artery chemotherapy can significantly improve the quality of life and prolong the survival time as well. Therefore, this technique is an effective therapy for advanced lung cancer and should be recommended in clinical practice. (authors)

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

    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

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

    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)

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

    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.)

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

    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 γ-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 μ Gy and effective dose 0.06- 1.81 μSv outside lead aprons and the highest absorbed dose 2.35 μ Gy and effective 0.02 μSv 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 μGy and effective dose 0.88-4.07 μSv outside lead aprons and the highest absorbed dose 2.22 μ Gy and effective dose 0.09 μSv 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 μGy and effective dose 0.35 -7.59 μSv outside lead aprons and the highest absorbed dose 4.09 μGy and effective 0.22 μSv 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 μGy and effective dose 0.83-17.96 μSv outside lead aprons and the highest absorbed dose 10.29 μGy and effective 0.5 μSv 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 μGy and effective dose 2.40-4.50 μSv outside lead aprons and the highest absorbed dose 7.77 μGy and effective 0.12 μSv 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 μGy and effective dose 4.48-10.06 μSv outside aprons and the highest absorbed dose 5.19 μGy and effective 0.16 μSv 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)

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

    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)

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

    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.)

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

    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)

  14. Erectile function after permanent 125I prostate brachytherapy for localized prostate cancer

    Njomnang Soh, Patrice; Delaunay, Boris; Thoulouzan, Matthieu; Jonca, Frederic; Bachaud, Jean Marc; Delannes, Martine; Soulie, Michel; Huyghe, Eric

    2013-01-01

    Background and purpose To analyze erectile function in men treated by prostate brachytherapy (PB) for localized prostate cancer. Material and methods Of a series of 270 sexually active men treated by PB, 241 (89%), mean age 65 yr (range, 43–80 yr), participated in a study on erectile function that was evaluated using the International Index of Erectile Function 5-item (IIEF-5) questionnaire before implantation and by postal survey after a mean follow-up of 36 months (range, 6–70 months). Resu...

  15. Treatment of Metastatic Spinal Tumors by Percutaneous Vertebroplasty versus Percutaneous Vertebroplasty Combined with Interstitial Implantation of 125I Seeds

    Background: As the most frequent bone metastasis, spinal metastases cause severe pain and damage to vertebral bodies such as spinal osteolytic destruction and compression fractures. To avoid the trauma and complications of open surgery, a minimally invasive procedure, percutaneous vertebroplasty (PVP), has recently been developed to treat metastatic spinal tumors. Purpose: To analyze the treatment outcomes of metastatic spinal tumors by percutaneous vertebroplasty (PVP) alone or PVP combined with interstitial implantation of 125I seeds. Material and Methods: 80 patients with metastatic spinal tumors were randomized to receive PVP alone (40 cases) or PVP combined with 125I seed implantation (40 cases). Digital subtraction angiography (DSA)-guided vertebroplasty was performed under local anesthesia, and acrylic bone cement was injected into the vertebra through a bone trocar to the center of the lesion, with or without simultaneous interstitial implantation of 125I seeds. Results: At 6-month follow-up, PVP combined with 125I seed implantation resulted in zero cases with complete relief (CR), 36 with partial relief (PR), four with no changes (NC), and zero with progression of disease (PD), while PVP alone without seed implantation resulted in 0 CR, 31 PR, 7 NC, and 2 PD. While the combined-treatment group and the single-PVP group showed overall clinical benefit rates without significant difference (100% and 95.0%, respectively), their visual analogue pain scales (VAS; 2.26±1.05 and 5.41±0.94, respectively) and Karnofsky performance scores (KPS; 92.5±7.1 and 87.7±7.3, respectively) were significantly different after treatment (P = 0.028 and P = 0.009, respectively). Patients in both groups had 1-year follow-up, and the mean time to tumor progression (TTP) was 9.0 and 8.9 months, respectively (not significant). Conclusion: PVP is a minimally invasive procedure with small wounds and minor complications. It is effective in the alleviation of pain in metastatic spinal tumor patients, and its clinical outcomes can be enhanced by the combination of interstitial implantation of 125I seeds

  16. Treatment of Metastatic Spinal Tumors by Percutaneous Vertebroplasty versus Percutaneous Vertebroplasty Combined with Interstitial Implantation of 125I Seeds

    Zuozhang Yang; Lin Xie; Yunchao Huang; Hongpu Sun; Pengjie Liu; Zhongxiong Wu (Dept. of Orthopedics, Tumor Hospital of Yunnan Province, Third Affiliated Hospital of Kunming Medical College, Kunming, Yunnan (China)). e-mail. yangzuozhang@163.com; Dakuan Yang (Second Affiliated Hospital of Kunming Medical College, Kunming Yunnan (China)); Yuqing Sun (Dept. of Orthopedic Oncology, Beijing Jishuitan Hospital, Beijing (China))

    2009-12-15

    Background: As the most frequent bone metastasis, spinal metastases cause severe pain and damage to vertebral bodies such as spinal osteolytic destruction and compression fractures. To avoid the trauma and complications of open surgery, a minimally invasive procedure, percutaneous vertebroplasty (PVP), has recently been developed to treat metastatic spinal tumors. Purpose: To analyze the treatment outcomes of metastatic spinal tumors by percutaneous vertebroplasty (PVP) alone or PVP combined with interstitial implantation of 125I seeds. Material and Methods: 80 patients with metastatic spinal tumors were randomized to receive PVP alone (40 cases) or PVP combined with 125I seed implantation (40 cases). Digital subtraction angiography (DSA)-guided vertebroplasty was performed under local anesthesia, and acrylic bone cement was injected into the vertebra through a bone trocar to the center of the lesion, with or without simultaneous interstitial implantation of 125I seeds. Results: At 6-month follow-up, PVP combined with 125I seed implantation resulted in zero cases with complete relief (CR), 36 with partial relief (PR), four with no changes (NC), and zero with progression of disease (PD), while PVP alone without seed implantation resulted in 0 CR, 31 PR, 7 NC, and 2 PD. While the combined-treatment group and the single-PVP group showed overall clinical benefit rates without significant difference (100% and 95.0%, respectively), their visual analogue pain scales (VAS; 2.26+-1.05 and 5.41+-0.94, respectively) and Karnofsky performance scores (KPS; 92.5+-7.1 and 87.7+-7.3, respectively) were significantly different after treatment (P = 0.028 and P = 0.009, respectively). Patients in both groups had 1-year follow-up, and the mean time to tumor progression (TTP) was 9.0 and 8.9 months, respectively (not significant). Conclusion: PVP is a minimally invasive procedure with small wounds and minor complications. It is effective in the alleviation of pain in metastatic spinal tumor patients, and its clinical outcomes can be enhanced by the combination of interstitial implantation of 125I seeds

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

    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)

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

    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.

  19. Permanent and removable implants for the brachytherapy of brain tumors

    Thirty-seven patients harboring primary or metastatic brain tumors were treated with 40 implantations of radioactive sources (192Ir, 198Au, or 125I) using stereotactic neurosurgical techniques. Most tumors had recurred after surgery, whole brain irradiation, and treatment with all feasible chemotherapeutic agents. Sixteen of the 40 implants were pregnant; 24 were mounted in plastic catheters for removal after the desired dose had been delivered. One or more sources were placed in each tumor to deliver 3500-7350 rad to the tumor's periphery for 198Au, 4,000-12,000 rad for 192Ir, and 3,000-20,000 rad for 125I. Three of the six patients treated with 192Ir had objective responses for 2, 4, and 12 months, and two stabilized for 8 and 11 months. Seven of the 11 patients treated with 198Au were evaluable: three responded for 3, 5, and 37 + months, one deteriorating patient with a recurrent tumor stabilized for 6 months, and two deteriorated despite treatment. One patient received an interstitial ''boost'' dose with 198Au after whole brain irradiation and stabilized for 15 months before developing spinal metastases. Six patients received permanent implants with low activity 125I. Three of these patients had blioblastomas or anaplastic astrocytomas; all continued to deteriorate despite the interstitial irradiation, presumably because the dose rat was too low. One patient with a low-grade astrocytoma (optic chiasm) responded dramatically to permanent, low activity 125I implants (11 + months). Another (hypothalamic glioma) had a permanent 125I implant, responded, as was stable at 9 months when external irradiation was administered. One patient with a suprasellar ''teratoid'' tumor stabilized for 10 months

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

    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

    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. Percutaneous transcatheter implantation of 125I iodine seeds for the treatment of liver cancer associated with portal vein tumor thrombus: initial experience in 19 cases

    Objective: To evaluate the feasibility and therapeutic efficacy of percutaneous transcatheter implantation of 125I iodine seeds in treating liver cancer associated with portal vein tumor thrombus. Methods: Nineteen patients with primary hepatocellular carcinoma complicated by portal vein tumor thrombus received implantation of 125I iodine seeds via portal vein. The puncturing of portal vein was guided by ultrasound. Under fluoroscopic guidance the 125I iodine seeds were implanted within the portal vein tumor thrombus at 8 mm distance. The number of 125I iodine seeds used in one procedure was 8 to 30 in total. The technical success rate, the postoperative complications, the hepatic and renal functions as well as routine blood test, and the suppression of portal vein tumor thrombus were determined, and the results were analyzed. Results: The implantation of 125I seeds was successfully accomplished in all the patients. No serious procedure-related complications occurred. During the follow-up period lasting for 3-22 months, the portal vein tumor thrombus showed a significant shrinkage in all patients. Conclusion: For the treatment of portal vein tumor thrombus, percutaneous transcatheter implantation of 125I iodine seeds is clinically feasible and effective. (authors)

  3. 125I interstitial implants in the RIF-1 murine flank tumor: an animal model for brachytherapy

    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

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

    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)

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

    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)

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

    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

  7. CT-guide coaxial 125I seeds implantation for the treatment of retroperitoneal lymph node metastasis: analysis of 21 cases

    Objective: To investigate the method, safety and clinical value of CT-guided coaxial percutaneous 125I seed implantation in treating retroperitoneal metastatic lymph nodes. Methods: CT-guided coaxial percutaneous 125II seed implantation, as interstitial brachytherapy, was carried out in 21 patients with retroperitoneal lymph node metastasis. Before operation therapeutic plan system (TPS) was used in all patients to design the distribution of radioactive particles, and after the procedure CT scanning was performed to verify the distribution of radioactive particles. After the treatment, the abdominal pain, abdominal distension, serum tumor marker levels and local reaction of the target lymph nodes were evaluated. Results: The technical success rate was 100%, and after the operation no serious complications such as gastrointestinal perforation, radiation enteritis, vascular injury, bleeding, etc. occurred. Follow-up CT scanning was conducted once every 1-2 months. Six months after the treatment, complete remission (CR) was obtained in 13 cases, partial remission (PR) in 6 cases, stable disease (SD) in 2 cases, and progression disease (PD) in none. The overall response (CR + PR) rate was 90.5%. The abdominal pain and abdominal distension were relieved in different degrees in 16 patients, and the serum tumor marker levels were decreased in different degrees in 14 patients. Conclusion: For the treatment of retroperitoneal lymph node metastasis, CT-guided coaxial percutaneous l25I seed implantation is effective, safe and reliable. This technique provides a new minimally-invasive treatment for retroperitoneal lymph node metastasis. (authors)

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

    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)

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

    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)

  10. CT-guided percutaneous vertebroplasty combined with 125I-seed implantation for metastatic vertebral carcinoma involving the spinal canal: analysis of 23 cases

    Objective: To evaluate the safety and efficacy of CT-guided percutaneous vertebroplasty (PVP) combined with 125I-seed implantation for the treatment of metastatic vertebral carcinoma involving the spinal canal. Methods: A total of 28 involved vertebrae were detected in 23 patients with metastatic vertebral carcinoma. Each patient had 1-2 diseased vertebrae. The lesions included cervical vertebra (n=4), thoracic vertebra (n=13) and lumbar vertebra (n=11). Destroyed posterior vertebral wall was seen in all involved vertebrae. Thirteen vertebrae found in 12 patients showed involvement of the epidural space. According to treatment planning system (TPS) CT-guided implantation of 125I seeds was carried out first for cervical lesions, which was followed by PVP. For the thoracic and lumbar lesions, unilateral or bilateral puncturing with several particle needles was employed to implant the 125I seeds, then, PVP with bone cement injection was performed. The complications and the clinical efficacy were analyzed. Results: Successful operation was obtained in all patients. The number of implanted 125I seeds ranged from 4 to 30 per vertebra, and the volume of injected bone cement was 1-6 ml per vertebra. After the operation the pain relief rate was 86.9% (n=20). The incidence of bone cement leakage was 17.8% (5/28). One patient had radicular pain caused by neuropore leakage, which was relieved after medication. No serious complications, such as spinal cord injury or radiation myelitis, occurred. Conclusion: CT-guided PVP combined with 125I-seed implantation is effective and safe for the treatment of metastatic vertebral carcinoma involving the spinal canal. This therapy can effectively relieve the pain and control the deterioration of tumor, besides, the incidence of bone cement leakage is very low. (authors)

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

    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.

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

    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)

  13. Inverse automated treatment planning with and without individual optimization in interstitial permanent prostate brachytherapy with high- and low-activity 125I

    Purpose: To determine whether dose distribution achieved with treatment plans using high- and low-activity 125I implants differs. Patients and Methods: Based on intraoperative transrectal ultrasound scans of 71 patients, inverse automated treatment plans (IATP) were performed with 15.5-kBq (0.42-mCi) and 25.2-kBq (0.68-mCi) 125I implants using a commercial 3-D planning system (Variseed trademark). A prescription dose of 145 Gy in 98% of the prostate volume (V100), a maximum dose to the urethra of 250 Gy (D1), and a maximum dose to 10% of the anterior rectal wall of 145 Gy (D10) were required. The plans were manually corrected, if necessary. Results: In the IATP, a better dose coverage of the prostate was found for high-activity seeds (V100 of 98% vs 84%). The prostate dose values increased with the prostate volume. After manual optimization, the differences were only marginal with a prostate V100 of 99% for both activities, a urethra D1 of 247 Gy and 239 Gy, and a rectum D10 of 135 Gy and 124 Gy for high- and low-activity seeds. Low-activity seeds required more sources (66 vs 47) and needles (24 vs 17; all numbers are median values). Conclusions: Concerning the prostate dose coverage, high-activity seeds are superior in the IATP. After manual adjustment, the dose values for the prostate and the organs at risk are similar. Considering a supposedly decreased toxicity and a shorter implantation time for a lower number of seeds, we recommend high-activity seeds for experienced teams. (orig.)

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

    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 shipme......)I, resulting in a lower variation for each SK value for each source (because the variations become averaged out statistically speaking)....

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

    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)

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

    Objective: To evaluate the clinical effects of CT-guided 125I radioactive seed implantation in treatment of stage Ⅲ non-small cell lung cancer (NSCLC) and the influential factors of prognosis. Methods: 247 patients of stage Ⅲa/Ⅲb 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 Ⅲ, patients. And the 5- year overall survival rate was 11.2%, and the median survival time was 24.0 months at the stage Ⅲb. 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 Ⅲ 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)

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

    '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)

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

    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

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

    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)

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

    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...

  1. Radiation protection after interstitial permanent prostate brachytherapy implants

    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)

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

    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

  3. Salvage low-dose-rate 125I partial prostate brachytherapy after dose-escalated external beam radiotherapy

    Chang, Lynn; Mark K. Buyyounouski

    2014-01-01

    Purpose To report outcomes on 5 patients treated with salvage partial low-dose-rate (LDR) 125-iodine (125I) permanent prostate seed brachytherapy (BT) for biopsy-proven locally persistent prostate cancer, following failure of dose-escalated external beam radiotherapy (EBRT). Material and methods A retrospective review of the Fox Chase Cancer Center prostate cancer database identified five patients treated with salvage partial LDR 125I seed implant for locally persistent disease following dose...

  4. The effect of local control on metastatic dissemination in carcinoma of the prostate: Long-term results in patients treated with 125I implantation

    The study evaluates the effect of the locally recurring tumor on the incidence of metastatic disease in early stage carcinoma of the prostate. The probability of distant metastases was studied in 679 patients with Stage B-C/N0 carcinoma of the prostate treated at MSKCC between 1970 and 1985 (median follow-up of 97 months). Patients were staged with pelvic lymph node dissection and treated with retropubic 125I implantation. The actuarial distant metastases free survival (DMFS) for patients at risk at 15 years after initial therapy was 37%. Cox proportional hazard regression analysis of covariates affecting the metastatic outcome showed that local failure, used in the model as a time dependent variable, was the most significant covariate, although stage, grade, and implant volume were also found to be independent variables. The relative risk of metastatic spread subsequent to local failure was 4-fold increased compared to the risk without evidence of local relapse. The 15-year actuarial DMFS in 351 patients with local control was 77% compared to 24% in 328 patients who developed local relapses (p less than 0.00001). The relation of distant spread to the local outcome was observed regardless of stage, grade, or implant dose. Even stage B1/N0-Grade I patient with local control showed a 15-year actuarial DMFS of 82%, compared to 22% in patients with local relapse (p less than 0.00001). The median local relapse-free survival (LRFS) in the 268 patients with local recurrences who did not receive hormonal therapy before distant metastases were detected was 51 months, compared to a median of 71 months for DMFS in the same patients (p less than 0.001), consistent with the possibility that distant dissemination may develop secondary to local failure

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

    '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)

  6. Permanent transvenous pacemaker implantation in forty dogs

    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

  7. Permanent iodine-125 implants in malignant gliomas

    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

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

    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)

  9. [125I]Iodopride

    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

  10. Quality of life after permanent prostate implant

    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

  11. Permanent Breast Seed Implant Dosimetry Quality Assurance

    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.

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

    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

  13. Permanent implants in treatment of prostate cancer

    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)

  14. Sealed radiation sources of 125I in radiosurgery

    The reviews of the application of a new method of interstitial irradiation using sealed 125I radiation sources in radiosurgery as an efficient and organ-preserving method of boral effect on the tumor are consided. 125I is an artificial radionuclide whose half-life equals 60.2 dayes and average photor radiation energy 28-35 keV. 125I sources are used for treating cancers of various localipations and metastases to lymph nodes of the neck. 125I sources are classified as a group of nonrewverable sources, i.e. they remain in the body forever. The paper describes different techniques of 125I source implantation used independently and in combination with other irradiation methods and various surgical interventions. It is shown that the application of 125I sources in combination with other therapeutic techniques is an efficient method of suppressing malignant tumor growtn

  15. Image fusion techniques in permanent seed implantation

    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.

  16. Antibiotic prophylaxis in permanent pacemaker implantation: a prospective randomised trial.

    Mounsey, J P; Griffith, M J; Tynan, M; Gould, F K; MacDermott, A F; Gold, R. G.; Bexton, R. S.

    1994-01-01

    BACKGROUND--Pacemaker pocket infection is a potentially serious problem after permanent pacemaker implantation. Antibiotic prophylaxis is commonly prescribed to reduce the incidence of this complication, but current trial evidence of its efficacy is conflicting. A large prospective randomised trial was therefore performed of antibiotic prophylaxis in permanent pacemaker implantation. The intention was firstly to determine whether antibiotic prophylaxis is efficacious in these patients and sec...

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

    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

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

    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

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

    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

    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. Permanent and temporary pacemaker implantation after orthotopic heart transplantation

    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.

  2. 192Ir or 125I prostate brachytherapy as a boost to external beam radiotherapy in locally advanced prostatic cancer: A dosimetric point of view

    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 85.38% for 192Ir LDR and 962% 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

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

    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 χ2 (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 

  4. The initial experience of 125I seeds brachytherapy for patients with oral carcinoma

    Objective: To evaluate the efficacy of 125I radioactive seeds implantation and 125I plaque brachytherapy for oral carcinoma. Methods: Eighteen patients with oral carcinoma confirmed by cytology or histopathology were included in this study, Twelve patients with tongue cancer and six patients with gingival carcinoma, there were 20 ulcerative lesions and 10 metastatic cervical lymph nodes. The mean diameter is (2.3±0.7) cm and (2.8±1.7) cm respectively. The patients were treated with both interstitial implantation of 125I seeds and 125I plaque brachytherapy or with 125I plaque brachytherapy only according to patient's individual conditions. The metastatic cervical lymph nodes were treated with CT-guided interstitial implantation of 125I seeds. The sizes of ulcerative lesions and lymph nodes were observed at 1,3,6 months following treatment, and statistical analysis of the sizes of ulcerative lesions were evaluated by paired t-test. Results: After 1,3,6 months follow-up, The mean diameters of ulcerative lesions were (2.1 ± 0.6 )cm (t=3.559, P125I implantation again. Patients were followed for 7 to 28 months, all patients were still alive. Conclusion: Interstitial 125I radioactive seeds implantation and 125I plaque brachytherapy provide an effective, sale treatment for oral cancer. (authors)

  5. Permanent and temporary pacemaker implantation after orthotopic heart transplantation

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

    2000-01-01

    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...

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

    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. Reevaluation of the indications for permanent pacemaker implantation after transcatheter aortic valve implantation

    Bjerre Thygesen, Julie; Loh, Poay Huan; Cholteesupachai, Jiranut; Franzen, Olaf; Søndergaard, Lars

    2014-01-01

    AIMS: Conduction abnormalities (CA) requiring permanent pacemaker (PPM) are a well-known complication after transcatheter aortic valve implantation (TAVI). This study aimed to determine the incidence of TAVI-related PPM and reevaluate the indications for PPM after the periprocedural period. METHODS...

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

    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. Comparison of MRI pulse sequences in defining prostate volume after permanent implantation

    Purpose: To determine the relative value of three MRI pulse sequences in defining the prostate volume after permanent implantation. Methods and Materials: A total of 45 patients who received a permanent 125I implant were studied. Two weeks after implantation, an axial CT scan (2 mm thickness) and T1-weighted, T1-weighted fat saturation, and T2-weighted axial MRI (3-mm) studies were obtained. The prostate volumes were compared with the initial ultrasound planning volumes, and subsequently the CT, T1-weighted, and T1-weighted fat saturation MRI volumes were compared with the T2-weighted volumes. Discrepancies in volume were evaluated by visual inspection of the registered axial images and the registration of axial volumes on the sagittal T2-weighted volumes. In a limited set of patients, pre- and postimplant CT and T2-weighted MRI studies were available for comparison to determine whether prostate volume changes after implant were dependent on the imaging modality. Results: T1-weighted and T1-weighted fat saturation MRI and CT prostate volumes were consistently larger than the T2-weighted MRI prostate volumes, with a volume on average 1.33 (SD 0.24) times the T2-weighted volume. This discrepancy was due to the superiority of T2-weighted MRI for prostate definition at the following critical interfaces: membranous urethra, apex, and anterior base-bladder and posterior base-seminal vesicle interfaces. The differences in prostate definition in the anterior base region suggest that the commonly reported underdose may be due to overestimation of the prostate in this region by CT. The consistent difference in volumes suggests that the degree of swelling observed after implantation is in part a function of the imaging modality. In patients with pre- and postimplant CT and T2-weighted MRI images, swelling on the T2-weighted images was 1.1 times baseline and on CT was 1.3 times baseline, confirming the imaging modality dependence of prostate swelling. Conclusion: Postimplant T2-weighted MRI images provided superior prostate definition in all critical regions of the prostate compared with CT and the other MRI sequences tested. In addition to defining an optimal technique, these findings call two prior observations into question. Under dosing at the anterior base region may be overestimated because of poor definition of the prostate-bladder muscle interface. The swelling observed after implantation was lower on T2-weighted images as well, suggesting that a fraction of postimplant swelling is a function of the imaging modality. These findings have implications for preimplant planning and postimplant evaluation. As implant planning techniques become more conformal, and registration methods become more efficient, T2-weighted MRI after implantation will improve the accuracy of postimplant dosimetry

  10. Permanent LDR implants in treatment of prostate cancer

    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)

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

    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)

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

    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.)

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

    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. χ2 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 (χ2=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 (χ2=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)

  14. Reevaluation of the indications for permanent pacemaker implantation after transcatheter aortic valve implantation

    Bjerre Thygesen, Julie; Loh, Poay Huan; Cholteesupachai, Jiranut; Franzen, Olaf; Søndergård, Lars

    2014-01-01

    AIMS: Conduction abnormalities (CA) requiring permanent pacemaker (PPM) are a well-known complication after transcatheter aortic valve implantation (TAVI). This study aimed to determine the incidence of TAVI-related PPM and reevaluate the indications for PPM after the periprocedural period. METHODS...... the patients who did not have a TAVI-related PPM implantation showed that the PR and QRS intervals increased following TAVI, reaching a peak on days 4-6 and 7-9, respectively, before decreasing to near baseline levels. CONCLUSION: Although the incidence of periprocedural PPM implantation following...... TAVI was high, most CAs following TAVI tend to resolve after the periprocedural period. This suggests that delaying the decision for PPM implantation after TAVI may reduce the PPM rate....

  15. [Leakage of gaseous 125I from a Na125I solution through a plastic film].

    Tanaka, Y

    1984-09-01

    Leakage of gaseous 125I from the various kinds of plastic film bags packing Na125I solution was determined. The polyethylene bag was permeable to the gaseous 125I and active charcoal could not prevent the leakage. The laminated plastic bags composed of polyethylene terephthalate and polyethylene was slightly permeable, and the leakage decreased either in the presence of active charcoal or with the use of doubly packed bags. Leakage of 125I from the various kinds of container for the Na125I solution was also determined. PMID:6240078

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

    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 γ=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.

  17. Preparation of 125I FSH hormone

    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)

  18. CT guided 125I seed brachytherapy for recurrent rectum cancer

    Objective: To investigate the technological feasibility, efficacy and morbidity of CT guided 125I seed implantation for recurrent rectum cancer. Methods: Twenty-three patients with recurrent rectum cancer were treated with CT guided interstitial 125I seed brachytherapy. In 20 patients the procedure was performed under epidural anesthesia and 3 patients under local anesthesia. Treatment planning system was used to calculate the number of seeds, the space distribution and the introduction of the seeding needles. Matched peripheral dose (MPD) of 121I seed implantation ranged from 90-120 Gy for patients who had had external radiotherapy, and 140- 160 Gy for those who had not. The planning target volume(PTV) was clinical target volume(CTV) plus 1 cm margin. The range of radioactivity of the 125I seeds was 18.5-25.9 MBq. All these 23 patients had CT scan at 5 mm intervals after implantation for quality evaluation, together with routine chest, pelvic X-ray films within 24-48 hours after seed implantation. Three patients received three-dimensional conformal radiation therapy(3DCRT) to a total dose of 45-50 Gy, with 2-3 Gy/f. Follow-up time was from 3 to 28 months. Results: All patients was able to tolerate seed implantation well. Complete pain relief was observed in 12/15, and partial relief in 2/15 and no response in 1/15, with a response rate of 93%. The local control rate was 87%. The 1- and 2-year survival rate was 93% and 50% respectively. Two of four patients have died of dissemination to the lung after 8 and 12 months. One seed has migrated into the pelvis without causing any untoward morbidity. Conclusion: CT guided 125I seed implantation for recurrent rectum cancer is safe, minimally invasive, causing only mild morbidity. It possesses a high efficacy, yet it should be given in combination with extemal beam radiation and chemotherapy, should distant metastasis be observed. (authors)

  19. Early complications of permanent pacemaker implantation: no difference between dual and single chamber systems.

    Aggarwal, R. K.; Connelly, D T; Ray, S.G.; Ball, J; Charles, R G

    1995-01-01

    OBJECTIVE--To evaluate the incidence of intraoperative and early postoperative complications (up to two months after implant) of endocardial permanent pacemaker insertion in all patients under-going a first implant at a referral centre. METHODS--Prospective evaluation of all endocardial pacemaker implantation procedures performed from April 1992 to January 1994 carried out by completion of standard audit form at implant. Patients' demographic data, medical history, details of pacemaker hardwa...

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

    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.

  1. Combination of multi-disciplinary techniques with 125I seeds in treating malignant obstructive jaundice

    Objective: To explore the effectiveness and safety of the combined multi-disciplinary techniques with 125I seeds to treat the malignant obstructive jaundice. Methods: 18 cases:of malignant obstructive jaundice were divided into 2 groups. A group with ERBD technique followed by CT-guided interstitial 125I seeds implantation, B group with 125I seeds implantation during the operation and gallbladder-intestine anastomosis later on. After 2 months amelioration (CR, PR,SD, PD) of the obstructive jaundice was observed with inspection of liver functions. Results: All cases were ameliorated with 44% patients in group A and 56% patients in group B, showing no significant statistical difference (P>0.05); and the liver functions were also relieved in both groups with no statistical significance (P>0.05). Conclusion: Multi-disciplinary techniques combined with 125I seeds implantation is effective in the management of the malignant obstructive jaundice. No significant difference for relief and liver function were found between CT-guided and during operation interstitial 125I seeds implantations, but it seems more quickly relief or recovery was achieved in the latter. (authors)

  2. Permanent pacemaker implanted into patient’s left ventricle via subclavian artery by mistake: a case report

    Tang, Guanmin; Zhai, Changlin; Wang, Zhiyong; CHEN, Hao

    2015-01-01

    Background Although various iatrogenic complications could be observed in the process of permanent pacemaker implantation, pacemaker electrode mistakenly implanted into left ventricle via subclavian artery and aortic valve has not been reported. Case presentation Herein, we reported a 71-year-old woman with permanent pacemaker mistakenly implanted into the left ventricle. During the operation of permanent pacemaker implantation, puncture was performed on her subclavian artery by mistake, and ...

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

    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.)

  4. Preparation of 125I labelled compound

    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)

  5. 125I and 125I-glucagon metabolism in rat liver

    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

  6. Preparation of 125I-creatine phosphokinase-MM

    125I-creatine phosphokinase-MM (125I-CPK-MM) was prepared by 125I-labelled Bolton-Hunter reagent (HPNS). Iodinating conditions of HPNS and its conjugation to protein were studied. 125I-CPK-MM with immune activity was obtained and used to establish the 125I-CPK-MM radioimmunoassay method by the General Hospital of PLA. 125I-CPK-MM in PBS-G solution containing 0.015 mol/l ethyl mercaptan at 4-10 deg C can be used for one month

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

    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.

  8. [Intraoperative and post-implant dosimetry in patients treated with permanent prostate implant brachytherapy].

    Herein, András; Ágoston, Péter; Szabó, Zoltán; Jorgo, Kliton; Markgruber, Balázs; Pesznyák, Csilla; Polgár, Csaba; Major, Tibor

    2015-06-01

    The purpose of our work was to compare intraoperative and four-week post-implant dosimetry for loose and stranded seed implants for permanent prostate implant brachytherapy. In our institute low-dose-rate (LDR) prostate brachytherapy is performed with encapsulated I-125 isotopes (seeds) using transrectal ultrasound guidance and metal needles. The SPOT PRO 3.1 (Elekta, Sweden) system is used for treatment planning. In this study the first 79 patients were treated with loose seed (LS) technique, the consecutive patients were treated with stranded seed (SS) technique. During intraoperative planning the dose constraints were the same for both techniques. All LSs were placed inside the prostate capsule, while with SS a 2 mm margin around the prostate was allowed for seed positioning. The prescribed dose for the prostate was 145 Gy. This study investigated prostate dose coverage in 30-30 randomly selected patients with LS and SS. Four weeks after the implantation native CT and MRI were done and CT/MRI image fusion was performed. The target was contoured on MRI and the plan was prepared on CT data. To assess the treatment plan dose-volume histograms were used. For the target coverage V100, V90, D90, D100, for the dose inhomogeneity V150, V200, and the dose-homogeneity index (DHI), for dose conformality the conformal index (COIN) were calculated. Intraoperative and postimplant plans were compared. The mean V100 values decreased at four-week plan for SS (97% vs. 84%) and for LS (96% vs. 80%) technique, as well. Decrease was observed for all parameters except for the DHI value. The DHI increased for SS (0.38 vs. 0.41) and for LS (0.38 vs. 0.47) technique, as well. The COIN decreased for both techniques at four-week plan (SS: 0.63 vs. 0.57; LS: 0.67 vs. 0.50). All differences were significant except for the DHI value at SS technique. The percentage changes were not significant, except the COIN value. The dose coverage of the target decreased significantly at four-week plans for both techniques. The decrease was larger for LS technique, but the difference between techniques was not significant at this patient number. The dose distribution was more homogenous, but the conformality was worse at four-week plans. PMID:26035163

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

    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. Postenucleation orbits in retinoblastoma: treatment with 125I brachytherapy

    Purpose: Children with retinoblastoma that extends into or through the choroid, sclera, or optic nerve are at risk of developing orbital disease, as well as metastases. Previously, these enucleated orbits were treated with external beam radiotherapy in addition to chemotherapy. 125I brachytherapy for tumors in and around the eye was pioneered by Sealy in Cape Town, South Africa, in 1974. In 1983, he developed a technique to irradiate the contents of the orbit while limiting the dose to the bony orbit and eyelids. Methods and Materials: Six nylon tubes containing 125I seeds were implanted through the eyelids around the periphery of the orbit. Each contained a metal gutter that screens the outer part of the seeds from the bony orbit. A seventh unscreened tube was placed in the center, and a metal disc with 125I seeds on its posterior surface was secured beneath the eyelids. Between 1983 and 2000, 57 orbits were treated in 56 children with retinoblastoma. Thirty-six were treated prophylactically and 21, with tumor at the resection line of the nerve, extrascleral tumor, or metastases, were treated therapeutically. They received a median dose of 34 Gy in 70 h; 30 also received chemotherapy. Children with tumor at the resection line of the nerve also received treatment to the craniospinal axis. Results: The median follow-up of the 35 patients treated prophylactically was 35 months (range 0-187). Seven patients died, 6 of metastases, at a median of 10 months (range 4-29) after the implant. Eight of the 13 patients with microscopic extraocular tumor survived a median of 29 months (range 5-156). None of the 8 patients presenting with orbital tumor or metastases survived. No orbital recurrences developed in any of the patients. Cosmesis was considerably improved compared with previous forms of irradiation. Conclusion: Orbital brachytherapy is an effective method of irradiating the orbit to prevent recurrent tumor, the treatment time is short, and the cosmesis is much more acceptable than with other forms of irradiation. No facial atrophy or second nonocular tumors have occurred

  11. Relation of QRS Width in Healthy Persons to Risk of Future Permanent Pacemaker Implantation

    Cheng, Susan; Larson, Martin G.; Keyes, Michelle J.; McCabe, Elizabeth L; Newton-Cheh, Christopher; Levy, Daniel; Benjamin, Emelia J.; Vasan, Ramachandran S.; Wang, Thomas J

    2010-01-01

    In the setting of acute myocardial infarction, prolongation of the QRS interval on an electrocardiogram identifies patients at risk of needing permanent pacemaker implantation. However, the implications of a prolonged QRS in healthy individuals are unclear, especially since the QRS prolongation encountered in this setting is typically mild. We studied the relation between QRS duration and incident pacemaker implantation in a community-based cohort of 8,311 individuals (mean age 54 years, 55% ...

  12. Studies on 125I contamination to various crops

    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

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

    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.

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

    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. Dosimetric results in implant and post-implant and low rate in brachytherapy prostate cancer with loose seeds and attached

    The objective is determine differences dosimetry statistics on the dosimetry of the implant and post-implant in brachytherapy of low rate with implants permanent in prostate using seed of 125-I loose and attached Both in lives and in the post-prostatic plans dosimetric coverage is good and restrictions in urethra and rectum for both groups of patients are met. Not migrating with joined is evident, as well as better dosimetric homogeneity. (Author)

  16. Self-expandable stent loaded with 125I seeds: Feasibility and safety in a rabbit model

    Objective: To evaluate technical feasibility and acute and subacute radiotolerance of a self-expandable stent loaded with 125I seeds in the rabbit esophagus. Methods: A self-expandable stent designed for esophageal application was made of 0.16 mm nitinol wire and loaded with 125I seeds (CIAE-6711). Twenty-seven stents with three different radioactive dosages (n = 9 in each dosage group) were implanted in the esophagus of healthy rabbits, while nine stents alone were used as controls. The stents were perorally deployed into the esophagus under fluoroscopic guidance. Radiological follow-up included plain chest film, CT scan, and barium esophagography which were undertaken in all rabbits of each group at 2, 4, and 8 weeks, respectively, which were correlated to histopathological findings. The stented esophageal segments along with their adjacent tissues were harvested for histopathological examinations. Results: The stent was successfully deployed into the targeted esophageal segment in all rabbits. Neither 125I seeds dislodged from the stent during the deployment, nor they did during the follow-up period. The greatest (16.2 Gy) absorbed dose was found in the tissue 10 mm from 125I seeds at 8 weeks. Slight epithelial hyperplasia on the stent surface and submucosal inflammatory process developed at 2 weeks, which reached the peak at 8 weeks after the procedure. Significant thickness of the esophageal muscular layer was found at 8 weeks only in the groups with 125I seeds. On radiologic follow-up, moderate strictures on both ends of the stents developed at 4 weeks and became severe at 8 weeks after the procedure in all groups. Conclusion: Deployment of a self-expandable stent loaded with 125I seeds is technically feasible and safe within the first 8 weeks. Acute and subacute radiotolerance of the treated esophagus and its adjacent tissues by 125I seeds is well preserved in a healthy rabbit model

  17. I-123 metaiodobenzylguanidine cardiac scintigraphy in patients with an implanted permanent pacemaker

    Tl scintigraphic abnormalities have been reported in patients with an implanted permanent pacemaker, but little is known about the MIBG scintigraphic findings in such patients. This study was performed to assess the MIBG scintigraphic findings in patients with an implanted permanent pacemaker, and to test the hypothesis that imaging characteristics of MIBG scintigraphy differ according to its mode. Twelve patients (4 men and 8 women, mean age: 72.4±9.5 years), who had undergone the implantation of a permanent pacemaker for bradyarrhythmias, underwent MIBG scintigraphy. The patients were divided into VVI pacemaker and DDD pacemaker groups. The tomograms were divided into nine segments and the MIBG defect in each segment scored on a scale ranging from 0 (normal uptake) to 3 (no uptake). Total MIBG defect scores were generated by summing the scores for the nine segments in each patient. MIBG scintigraphic abnormalities were found in ten of the twelve patients. The six patients with the VVI pacemaker manifested MIBG scintigraphic abnormalities. These MIBG scintigraphic abnormalities were observed in all segments, particularly in the posterior segments. The mean total defect score of the VVI group was higher than that of the DDD group (14.8±9.8 vs 3.0±3.5, respectively p<0.05). Therefore, we conclude that despite several limitations of the study, MIBG scintigraphic abnormalities occur in patients with implanted permanent pacemakers, and that such abnormalities are more prominent with the VVI than DDD pacemaker. (author)

  18. 78 FR 41125 - Interim Enforcement Policy for Permanent Implant Brachytherapy Medical Event Reporting

    2013-07-09

    ... Register on August 6, 2008 (73 FR 45635). The vast majority of commenters offered no objection to... COMMISSION Interim Enforcement Policy for Permanent Implant Brachytherapy Medical Event Reporting AGENCY... discretion for certain violations of regulations for reporting medical events occurring under an NRC...

  19. Decontamination of 125I in Medical Laboratory

    A radiological laboratory for diagnoses was contaminated by 125I. A large-scale survey of gamma-radiation has been made in different locations of the floors and walls of the lab to determine the contaminated area and its activity. The activity level before decontamination for the wall and floor was 1400 and 2000 Bq/cm2 respectively. Decontamination was carried out by using ethyl alcohol, potassium permanganate, ethylene diamine tetracetic acid and tissue papers. Decontamination factor has been calculated and it was 175 and 200 for the wall and floor respectively. D and D computer code has been used to calculate Total Effective Dose Equivalent (TEDE). TEDE from the wall and floor before decontamination were 3.05 and 4.35 ( mSv/yr ) while after decontamination were 18 and 23μSv/yr respectively. These results are lower than the Egyptian and the international regulations (10 mSv/y for the public ) according to International Atomic Energy agency, IAEA, Safety Series, SS, no. 115 (1994).

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

    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

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

    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)

  2. The contamination on farm products from 125I

    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

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

    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 ?Svm2MBq-1h-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. Computational Program of Isodose and TPS of 125I Seed for Brachytherapy

    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)

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

    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)

  6. Dual functional polyelectrolyte multilayer coatings for implants: permanent microbicidal base with controlled release of therapeutic agents.

    Wong, Sze Yinn; Moskowitz, Joshua S; Veselinovic, Jovana; Rosario, Ryan A; Timachova, Ksenia; Blaisse, Michael R; Fuller, Renée C; Klibanov, Alexander M; Hammond, Paula T

    2010-12-22

    Here we present a new bifunctional layer-by-layer (LbL) construct made by combining a permanent microbicidal polyelectrolyte multilayered (PEM) base film with a hydrolytically degradable PEM top film that offers controlled and localized delivery of therapeutics. Two degradable film architectures are presented: (1) bolus release of an antibiotic (gentamicin) to eradicate initial infection at the implant site, or (2) sustained delivery of an anti-inflammatory drug (diclofenac) to cope with inflammation at the site of implantation due to tissue injury. Each degradable film was built on top of a permanent base film that imparts the implantable device surface with microbicidal functionality that prevents the formation of biofilms. Controlled-delivery of gentamicin was demonstrated over hours and that of diclofenac over days. Both drugs retained their efficacy upon release. The permanent microbicidal base film was biocompatible with A549 epithelial cancer cells and MC3T3-E1 osteoprogenitor cells, while also preventing bacteria attachment from turbid media for the entire duration of the two weeks studied. The microbicidal base film retains its functionality after the biodegradable films have completely degraded. The versatility of these PEM films and their ability to prevent biofilm formation make them attractive as coatings for implantable devices. PMID:21105659

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

    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

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

    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.

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

    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

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

    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

  11. Immunoreactivity of 125I-papain labelled by different methods

    Three different methods of papain iodination (with chloramine-T, lactoperoxidase and conjugation with Bolton-Hunter reagent) have been compared. The highest yield of 125I-papain could be obtained using lactoperoxidase which enabled to achieve the highest immunoreactivity. 125I-papain, labelled this way, is suitable for the radioimmunoassay of papain. (author)

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

    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

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

    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. Safety handling of 125I in animal experiments

    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)

  15. Preparation and metabolism of 125I-sulfobromophthalein

    Metabolism of 125I-sulfobromophthalein (BSP) prepared by the chloramine-T method was studied in rats. 125I-BSP is removed rapidly from the circulation. However, as compared to BSP, its plasma clearance and biliary excretion are delayed, and its accumulation in the liver is prolonged. Although BSP and 125I-BSP show similar binding to albumin in serum, their binding properties to liver cytosolic proteins and to the liver cell plasma membrane organic anion binding protein (OABP) differ. In contrast to the X-, Y- and Z-protein binding of BSP, 125I-BSP binds predominantly to a high molecular weight protein and only a small proportion of 125I-BSP binds to OABP. (Auth.)

  16. Dual Functional Polyelectrolyte Multilayer Coatings for Implants: Permanent Microbicidal Base with Controlled Release of Therapeutic Agents

    Wong, Sze Yinn; Moskowitz, Joshua S.; Veselinovic, Jovana; Rosario, Ryan A.; Timachova, Ksenia; Blaisse, Michael R.; Smith, Renée C.; KLIBANOV, ALEXANDER M.; HAMMOND, PAULA T.

    2010-01-01

    Here we present a new bifunctional layer-by-layer (LbL) construct made by combining a permanent microbicidal polyelectrolyte multilayered (PEM) base film with a hydrolytically degradable PEM top film that offers controlled and localized delivery of therapeutics. Two degradable film architectures are presented: 1) bolus release of an antibiotic (gentamicin) to eradicate initial infection at the implant site, or 2) sustained delivery of an anti-inflammatory drug (diclofenac) to cope with inflam...

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

    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

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

    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

  19. Experimental study on H22 hepatoma treated by 125I seeds interstitial brachytherapy

    Objective: To evaluate the effectiveness of 125I seeds interstitial brachytherapy in the treatment of H22 hepatoma in mice and to observe the influence on the surrounding tissues and organs. Methods: Twenty days after the establishment of H22 hepatoma in mice models (n=20), all mice were anesthetized by intraperitoneal injection of 10% chloral hydrate (0.4 g/kg), and the tumor mass measured after laparotomy was about 0.49 cm in average diameter. 125I seeds were implanted into the tumors and then irradiated the tumors for 10 d. Then mice were anesthetized again and the 125I seeds were removed. The size of tumors was re-measured. Whole blood counts, liver function tests, pathologic examinations and electronic microscope of tumor tissues, surrounding liver and intestine tissues were performed. The expression of proliferating cell nuclear antigen (PCNA) was evaluated by immunohistochemical method. Results: After irradiation all mice were alive, and the average diameter of tumors was about 0.23 cm [P0.05, as compared with normal group (n= 10)]; Hb, RBC and PLT had no distinct change, but WBC decreased obviously (P125I seed interstitial brachytherapy is a feasible and effective method for the treatment of H22 hepatoma in mice, but also has certain influence on the surrounding tissues and organs. (authors)

  20. Preparation and evaluation of serotonin labelled with 125I

    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)

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

    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)

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

    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

  3. 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

    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.)

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

    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.

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

    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

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

    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

  7. Synthetic heparinoids labelled with 125I and 35S

    Sederel, L.C.; Kolar, Z.; Does, van der, Leen; Bantjes, A.

    1982-01-01

    The labelling of a water-soluble synthetic polyelectrolyte, having anticoagulant activity, has been studied. The polyelectrolyte is derived from cis-1,4-polyisoprene and contains N-sulfate and carboxylate groups. [125I]-Iodination of the polyelectrolyte, using the Chloramine-T method and an electrolytic method, resulted in a [125I]-labelled polyelectrolyte from which release of the label occurred. Resulfation of a partially desulfated polyelectrolyte with a [35S]-sulfur trioxide trimethylamin...

  8. Preparative HPLC separation of glycocholic acid-(125I-histamine)

    A preparative HPLC separation method of glycocholic acid-(125I-histamine) is described. The separation was carried out on YWG-CH reverse phase column by using methanol:isopropanol:water (60:5:40,V/V) as mobile phase. THe separation was 30 min. The flow rate was 1ml/min. Using this method, glycocholic acid-(125I-histamine) was purified and satisfactorily used for RIA. The radiochemical purity was 98%. The recovery efficiency was 99.1%

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

    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)

  10. Preparation of 125I-oestradiol-6-oxime-iodohistamine

    Using oestradiol-17β as a starting material, oestradiol-6-oxime-histamine and 125I-oestradiol-6-oxime-iodohistamine are synthetized. Purified by thin layer chromatography (T.L.C) plate at a specific acivity about 74 MBq/μg determined by self-displacement method, 125I-oestradiol-6-oxime-iodohistamine shows a high stability and a fine immunoreactivity tested by excess antibody binding. Its suitability is suitable for the tracer of radioimmunoassay (RIA)

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

    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)

  12. Utility of the NavX® Electroanatomic Mapping System for Permanent Pacemaker Implantation in a Pregnant Patient with Chagas Disease.

    Velasco, Alejandro; Velasco, Victor Manuel; Rosas, Fernando; Cevik, Cihan; Morillo, Carlos A

    2013-01-01

    Chagas disease is a highly prevalent zoonosis in Mexico, Central, and South America. Early cardiac involvement is one of the most serious complications of this disease, and conduction disturbances may occur at an early age. We describe a young pregnant woman with Chagas disease and a high degree atrioventricular block, who required implantation of a permanent dual chamber pacemaker. Using an electroanatomic navigation EnSite NavX® system the pacemaker was successfully implanted with minimal fluoroscopic exposure. This case demonstrates the safety and feasibility of using an electroanatomic navigation system to guide permanent pacemaker implantation minimizing x-ray exposure in pregnant patients. PMID:23329872

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

    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)

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

    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

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

    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)

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

    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.)

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

    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

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

    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)

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

    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)

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

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

    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

  2. Cytotoxicity of an 125I-labelled DNA ligand

    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

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

    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.

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

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

    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)

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

    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

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

    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 μg 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

  8. Utility of the NavX® Electroanatomic Mapping System for Permanent Pacemaker Implantation in a Pregnant Patient with Chagas Disease

    Velasco, Alejandro; Velasco, Victor Manuel; Rosas, Fernando; Cevik, Cihan; Morillo, Carlos A

    2013-01-01

    Chagas disease is a highly prevalent zoonosis in Mexico, Central, and South America. Early cardiac involvement is one of the most serious complications of this disease, and conduction disturbances may occur at an early age. We describe a young pregnant woman with Chagas disease and a high degree atrioventricular block, who required implantation of a permanent dual chamber pacemaker. Using an electroanatomic navigation EnSite NavX® system the pacemaker was successfully implanted with minimal f...

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

    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

    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. Chemical influence on the decay constant of 125I

    The chemical influence on the electron capture decay of 125I has been studied. The decay constant difference between NaIO3 and Na2H3IO6 has been assessed and measured. The results obtained are discussed in terms of the isomer shift of Moessbauer iodine isotopes

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

    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

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

    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)

  14. Retrospective analysis of 1650 permanent pacemaker implantations experience over two different consecutive time periods in a single cardiology clinic

    Serdar Bayata

    2010-04-01

    Full Text Available Objective: Indications for pacing, pacing modes, and demographics of patients who underwent pacemaker implantation between two different time periods were compared in this study.Methods: Pacemaker registry of our cardiology department was used to evaluate these changes from 1986 to 2007 (First period: 1986-1996, second period: 1997-2007 retrospectively. Results: Registry revealed 776 implantations in the first and 874 implantations in the second period. The percentages of first implantation were 89% and 70.1% respectively. Nearly 50% of the patients in both periods were female. Main indications for pacing were atrioventricular (AV block, sick sinus syndrome (SSS and slow ventricular rate during atrial fibrillation in both periods. Implantation of VVI-AAI pacemakers have decreased (77.8%/1.5% to 51%/0.3%, p<0.05 and implantation of DDD-VDD pacemakers have increased (19.3%/1.3% to 42.3%/6.3%, p<0.05 during the second period compared to the first period. Permanent pacemaker implantation for SSS has decreased significantly from 31.1% in the first period to 12.0% (p<0.05 in the second period. Implantation for AV block has increased significantly from 63.3% to 79.7% (p<0.05 in the second period.Conclusion: Our data revealed temporal changes in pacemaker implantation practice during last twenty years in the cardiology department of a teaching hospital. Implantation of VVI-AAI pacemakers have decreased significantly during the second period. Permanent pacemaker implantation for AV block has also decreased during the last period.

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

    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

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

    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)

  17. Preparation and evaluation of 125I-aflatoxin B1

    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)

  18. Class solution for inversely planned permanent prostate implants to mimic an experienced dosimetrist

    The purpose of this paper is to present a method for the selection of inverse planning parameters and to establish a set of inverse planning parameters (class solution) for the inverse planning included in a commercial permanent prostate implant treatment planning system. The manual planning of more than 750 patients since 1996 led to the establishment of general treatment planning rules. A class solution is tuned to fulfill the treatment planning rules and generate equivalent implants. For ten patients, the inverse planning is compared with manual planning performed by our experienced physicist. The prostate volumes ranged from 17 to 51 cc and are implanted with low activity I-125 seeds. Dosimetric indices are calculated for comparison. The inverse planning needed about 15 s for each optimization (400 000 iterations on a 2.5 GHz PC). In comparison, the physicist needed about 20 min to perform each manual plan. A class solution is found that consistently produces dosimetric indices equivalent or better than the manual planning. Moreover, even with strict seed placement rules, the inverse planning can produce adequate prostate dose coverage and organ at risk protection. The inverse planning avoids implant with seeds outside of the prostate and too close to the urethra. It also avoids needles with only one seed and needles with three consecutive seeds. This reduces the risk of complication due to seed misplacement and edema. The inverse planning also uses a smaller number of needles, reducing the cause of trauma. The quality of the treatment plans is independent of the gland size and shape. A class solution is established that consistently and rapidly produces equivalent dosimetric indices as manual planning while respecting severe seed placement rules. The class solution can be used as a starting point for every patient, dramatically reducing the time needed to plan individual patient treatments. The class solution works with inverse preplanning, intraoperative inverse preplanning, and intraoperative real-time planning. This technology is not intended to replace the physicist but to accelerate the planning process, making intraoperative treatment planning more effective

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

    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)

  20. Absolute measurement of the 125I desintegration rate

    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)

  1. Preparation of 19-iodocholesterol labelled with 125 I

    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

  2. Preparation of [125I]thyroxine by isotopic exchange

    The method is described of [125I]thyroxine preparation by isotopic exchange. Using the method, preparations were obtained of a specific activity of around 4,000 MBq/mg. The preparations are more pure and stable than those prepared by other methods using iodination agents which can cause product degradation. In actual conditions, the reaction yield ranged around 85%; discussed are the effects of the individual reaction conditions. Data on the preparation stability are shown. (author)

  3. 125I-interleukin-8: radiolabeling and distribution in mice

    Purpose: To study the radioiodinating condition of interleukin-8 (IL-8) and observe its biodistribution in mice for understanding the possibility of its application in nuclear medicine. Methods: IL-8 is labeled by 125I with Bolton-hunter regent and the distribution in mice at 5 min, 30 min, 1h, 6h and 24h after injection of 125I -IL-8 are meseared. The blood clearance curve is obtained and fitted with two-compartment model. Results: 125I-IL-8 is obtained with a labeling efficiency of 12.2%±6.5% and radiochemical purity of 91.4%±6.5%. Its specific activity is 14.8 kBq/μg IL-8. A fast phase half-life Tl/2α of 0.32 h and slow phase half - life T1/2β of 8.01 h are calculated from blood clearance curve. The uptakes of radioactivities in kidneys and lung have the peaks of 85.87% ID /g and 16.17% ID/g at 30 min after intravenous injection, respectively. The uptakes in liver and spleen are 12.05% ID /g and 8.97% ID/g as the maximum at 5 min after injection. The clearance in blood and other organ is fast. Except for kidneys and lung, 125I -IL-8 is less than 1% ID/ g 24h after administration. Conclusion: Radioiodinated IL-8 is a promising radiopharmaceutical in nuclear medicine, especially for imaging infection. But to enhance the labeling efficiency of radioiodinated IL-8 and to decrease its in vivo deiodination are necessary. (authors)

  4. Labeling Lanreotide with 125I and 188Re

    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

  5. Long term results of 125I for treatment of hyperthyroidism

    125I emits very low energy conversion and Auger electrons. This radionuclide has been used in place of 131I with the hope of reducing the incidence of post treatment hypothyroidism. 303 of 360 patients treated have been reviewed. Originally very large doses of 125I were prescribed (751-1,600 μCi/g) but 9 out of 15 patients (60%) became hypothyroid, therefore 4 smaller therapeutic regimes were employed. (1) 55 patients received doses of 200 μCi or less/g thyroid, 69% are euthyroid and 24% hypothyroid after an average of 33 months from treatment. (2) 87 patients received doses of 201-350 μCi/g thyroid, 67% are euthyroid and 21% hypothyroid after an average follow up of 30 months. (3) 70 patients received doses of 351-500 μCi/g thyroid, 77% are euthyroid and 18% hypothyroid 36 months after treatment and (4) 76 patients received doses of 501-750 μCi/g, 41% are euthyroid and 56% hypothyroid 49 months after therapy. No long term complications such as thyroid cancer or leukaemia have occurred but because 125I does not eliminate or reduce the incidence of post treatment hypothyroidism it probably should not be used in preference to 131I for the routine treatment of hyperthyroidism

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

    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

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

    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

  8. The influence of repopulation kinetics on isoeffect doses for permanent implants

    To calculate the isoeffective doses a model is used which describes the number of clonogenic tumor cells as a function of time. The effective irradiation time for permanent inplants depends on the half-life T1/2 of the used isotope. During the irradiation tumor cells may repopulate, an effect which is well known in fractionated radiotherapy. The longer the radiation treatment lasts the more dose will be needed to kill these repopulating tumor cells. A differential equation has been constructed where cell kill is determined by an α-β term and cell proliferation by a constant tumor cell doubling time Tpot. The solution of the differential equation gives the number of clonogenic tumor cells as a function of time. For our model an analytic solution has been found. The number of repopulating tumor cells shows a minimum if the dose rate is sufficiently high. Otherwise cell kill be radiation is overcompensated by growing tumor cells. The minimum value Nmin of tumor cells depends on the initial cell number N0, the total dose Dtot, the half-life T1/2 of the implant, the half-life Tr for repair of the sublethal damage, the α and β values of the tumor cells, and the effective clonogen doubling time Tpot of the tumor. Assuming that the tumor is cured if no clonogenic cell survives, the tumor control probability (TCP) is determined by the Poisson statistics TCP=exp(-Nmin). Isoeffective doses are doses with constant TCP. Isoeffective doses Dtot have been calculated for different Tpot as a function of the half-life T1/2 of the isotope. The model allows the calculation of isoeffective doses for permanent impants. Care must be taken to use the results in clinical practice unless all of the radiobiological parameters are known for a specific tumor. (orig.)

  9. Ultracompact, completely implantable permanent use electromechanical ventricular assist device and total artificial heart.

    Honda, N; Inamoto, T; Nogawa, M; Takatani, S

    1999-03-01

    An ultracompact, completely implantable permanent use electromechanical ventricular assist device (VAD) and total artificial heart (TAH) intended for 50-60 kg size patients have been developed. The TAH and VAD share a miniature electromechanical actuator that comprises a DC brushless motor and a planetary roller screw. The rotational force of the motor is converted into the rectilinear force of the roller screw to actuate the blood pump. The TAH is a one piece design with left and right pusher plate type blood pumps sandwiching an electromechanical actuator. The VAD is one half of the TAH with the same actuator but a different pump housing and a backplate. The blood contacting surfaces, including those of the flexing diaphragm and pump housing, of both the VAD and TAH were made of biocompatible polyurethane. The diameter, thickness, volume, and weight of the VAD are 90 mm, 56 mm, 285 cc, and 380 g, respectively, while those of the TAH are 90 mm, 73 mm, 400 cc, and 440 g, respectively. The design stroke volume of both the VAD and TAH is 60 cc with the stroke length being 12 mm. The stroke length and motor speed are controlled solely based on the commutation signals of the motor. An in vitro study revealed that a maximum pump flow of 7.5 L/min can be obtained with a pump rate of 140 bpm against a mean afterload of 100 mm Hg. The power requirement ranged from 4 to 6 W to deliver a 4-5 L/min flow against a 100 mm Hg afterload with the electrical-to-hydraulic efficiency being 19-20%. Our VAD and TAH are the smallest of the currently available devices and suitable for bridge to transplant application as well as for permanent circulatory support of 50-60 kg size patients. PMID:10198717

  10. Preparation of 19-iodo cholesterol labelled with 125 I; Preparacion del 19-yodocolesterol marcado con 125 I

    Rodriguez, L.; Rebollo, D. V.; Ruiz, J. M.

    1986-07-01

    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.

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

    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.)

  12. Synthesis and radioimmunological characterization of testosterone-3-carboxymethyloxime-tyramine-125 I (T-3-Cmo-Ty-125 I)

    The paper presents the synthesis and radioimmunological characterization of testosterone-3-carboxymethyloxime-tyramine-15 I (T-3-CMO-Ty-125 I), a reagent used as marker in radioimmunoassay (RIA) of steroid hormones. Some of the most adequate techniques of analyzing the steroid hormones are RIA and ELISA (enzyme linked immunosorbent assay) due to their sensitivity and specificity. These techniques do not require advanced purification of the sample. In the view of developing a sensitive RIA technique for assaying the testosterone-3-carboxymethyloxime-tyramine-125 I it is necessary to obtain the reagents as anti-testosterone antibody and radioactive labeled testosterone. The carboxy derivative of the steroid hormone was activated with ethylchloroformiate and tributylamine in dioxan and coupled with tyramine-125 I. Tyramine was labelled by chloramine method. The marker was purified by thin layer chromatography and extracted in methylic alcohol. Radioimmunological characterization of the marker was carried out with the help of the anti testosterone antibody obtained in our laboratory. (authors)

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

    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.

  14. The selection criteria of temporary or permanent luting agents in implant-supported prostheses: in vitro study

    Gonzalez-Gonzalez, Ignacio; Brizuela-Velasco, Aritza; Ellacuria-Echebarria, Joseba

    2016-01-01

    PURPOSE The use of temporary or permanent cements in fixed implant-supported prostheses is under discussion. The objective was to compare the retentiveness of one temporary and two permanent cements after cyclic compressive loading. MATERIALS AND METHODS The working model was five solid abutments screwed to five implant analogs. Thirty Cr-Ni alloy copings were randomized and cemented to the abutments with one temporary (resin urethane-based) or two permanent (resin-modified glass ionomer, resin-composite) cements. The retention strength was measured twice: once after the copings were cemented and again after a compressive cyclic loading of 100 N at 0.72 Hz (100,000 cycles). RESULTS Before loading, the retention strength of resin composite was 75% higher than the resin-modified glass ionomer and 2.5 times higher than resin urethanebased cement. After loading, the retentiveness of the three cements decreased in a non-uniform manner. The greatest percentage of retention loss was shown by the temporary cement and the lowest by the permanent resin composite. However, the two permanent cements consistently show high retention values. CONCLUSION The higher the initial retention of each cement, the lower the percentage of retention loss after compressive cyclic loading. After loading, the resin urethane-based cement was the most favourable cement for retrieving the crowns and resin composite was the most favourable cement to keep them in place.

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

    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)

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

    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

  17. Particle-rotor-model calculations in 125I

    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 identification of the unfavoured ℎ11/2 band showing very large signature splitting. In the present work, particle-rotor-model calculations have been performed for the ℎ11/2 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.

  18. Use of transesophageal atrial pacing to provide temporary chronotropic support in a dog undergoing permanent pacemaker implantation.

    Sanders, Robert A; Green, Henry W; Hogan, Daniel F; Sederquist, Kim

    2011-09-01

    A 14.5-kg, 13-year-old female spayed Cocker spaniel was evaluated because of episodic hind limb weakness. Results of examination were consistent with sick sinus syndrome with intermittent second-degree atrioventricular block. Transesophageal atrial pacing was successful in providing chronotropic support during permanent pacemaker implantation. Transesophageal atrial pacing appears to be a viable option for temporary atrial pacing in dogs with hemodynamically marked bradycardia without significant atrioventricular blockade. PMID:21813344

  19. Analysis of a five year experience of permanent pacemaker implantation at a Nigerian Teaching Hospital: need for a national database

    Falase, Bode; Sanusi, Michael; Johnson, Adeyemi; Akinrinlola, Fola; Ajayi, Reina; Oke, David

    2013-01-01

    Introduction Permanent pacemaker implantation is available in Nigeria. There is however no national registry or framework for pacemaker data collection. A pacemaker database has been developed in our institution and the results are analyzed in this study. Methods The study period was between January 2008 and December 2012. Patient data was extracted from a prospectively maintained database which was designed to include the fields of the European pacemaker patient identification code. Results ...

  20. Radio synthesis and in vivo evaluation of two α7 nAChRs radioligands. [125I]CAIPE and [125I]IPPU

    The radio synthesis and in vivo evaluation of two α7 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)

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

    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)

  2. 125I iothalamate an ideal marker for glomerular filtration

    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

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

    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)

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

    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,θ), Λ, gL(r), F(r, θ), φan(r), and φan 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,θ), was determined to be 2.5%, dominated by the uncertainties in the cross sections. The anisotropy constant, φan, 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

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

    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)

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

    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 1.620.06, 5.930.23, and 8.410.33% for adipose, air, and bone, respectively. (author)

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

    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)

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

    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)

  9. Consumption of 125I labelled fibrinogen in normal subjects

    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 μCi 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

  10. Highly deformed high-spin band in 125I

    High-spin states in 125I have been investigated using the reaction 82Se(48Ca, p4n) at a beam energy of 200 MeV and γ-ray coincidence events were detected using the Gammasphere spectrometer. A deformed rotational band, extending up to Iπ=95/2-, was observed for the first time in a heavier odd-A iodine nucleus. The characteristics of the band are very similar to those of the highly deformed bands observed recently in neighboring nuclei and it is essentially identical to one of the previously known bands in 126Xe. The experimental results are compared to cranked Nilsson-Strutinsky calculations and possible configurations for the band are discussed.

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

    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

  12. Pharmacokinetics and organ distribution of 125I-aprindine

    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)

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

    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)

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

    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)

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

    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, θ) 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)

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

    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.

  17. Study on non-coplanar intensity modulated radiation therapy in esophageal carcinoma implanted with permanent cardiac pacemaker

    The aim is to evaluate the physical dose distributions in esophageal carcinoma implanted with permanent cardiac pacemaker treated with non-coplanar intensity modulated radiation therapy (no-co-IMRT). Eight patients with esophageal carcinoma implanted cardiac pacemaker proven by histology were treated by IMRT. For each patient, we designed two IMRT plans by Eclipse IMRT inverse plan system: non-coplanar IMRT plan (3 coplanar fields and 2 non-coplanar fields) and coplanar IMRT plan (5 coplanar fields). The same physical parameter was applied to the same patient in both plans. Plans were evaluated in terms of dose-volume histogram, conformity index, homogeneity index monitor unit and control points. The results showed that no-co-IMRT plan could significantly reduce the max dose of implantable cardiac pacemaker and the wires (p<0.05), but no significant difference was found between no-co-IMRT plan and co-IMRT plan in target volume and other normal tissues Compared with co-IMRT plan, the monitor unit (MU) and control points of no-co-IMRT plan were not increased significantly (p>0.05). These findings indicate that the technique of no-co-IMRT can obtain the fewer max dose of implantable cardiac pacemaker and the wires during intensity modulated radiation therapy of esophageal carcinoma. (authors)

  18. One-year cardiac morphological and functional evolution following permanent pacemaker implantation in right ventricular septal position in chagasic patients

    Otaviano da Silva Júnior

    2012-06-01

    Full Text Available INTRODUCTION: The septal position is an alternative site for cardiac pacing (CP that is potentially less harmful to cardiac function. METHODS: Patients with Chagas disease without heart failure submitted to permanent pacemaker (PP implantation at the Clinics Hospital of the Triângulo Mineiro Federal University (UFTM, were selected from February 2009 to February 2010. The parameters analyzed were ventricular remodeling, the degree of electromechanical dyssynchrony (DEM, exercise time and VO2 max during exercise testing (ET and functional class (NYHA. Echocardiography was performed 24 to 48h following implantation and after one year follow-up. The patients were submitted to ET one month postprocedure and at the end of one year. RESULTS: Thirty patients were included. Patient mean age was 59±13 years-old. Indication for PP implantation was complete atrioventricular (AV block in 22 (73.3% patients and 2nd degree AV block in the other eight (26.7%. All patients were in NYHA I and no changes occurred in the ET parameters. No variations were detected in echocardiographic remodeling measurements. Intraventricular dyssynchrony was observed in 46.6% of cases and interventricular dyssynchrony in 33.3% of patients after one year. CONCLUSIONS: The findings of this work suggest that there is not significant morphological and functional cardiac change following pacemaker implantation in septal position in chagasic patients with normal left ventricular function after one year follow-up. Thus, patients may remain asymptomatic, presenting maintenance of functional capacity and no left ventricular remodeling.

  19. A Radiation Badge Survey for Family Members Living With Patients Treated With a 103Pd Permanent Breast Seed Implant

    Purpose: Sixty-seven patients with early-stage breast cancer were treated in a Phase I/II clinical trial using a 103Pd permanent breast seed implant as adjuvant radiotherapy after breast-conserving surgery. We report the dose received by family members living with these patients and compare measured doses with theoretical worst-case scenario estimates. Methods and Materials: Exposure-rate measurements were taken at 1 m from the patient by using a calibrated low-energy survey meter. Landauer (Landauer Inc., Glenwood, IL) Luxel badges, with sensitivity of 0.01 mSv, were given to family members to wear after the implantation. Badge readings for 33 spouses and 28 other family members were used to estimate effective doses, and these were compared with theory. Results: Average preimplantation planning target volume from computed tomography was 50.3 ml (range, 18.0-96.7 ml), and average preimplantation distance between the skin and the most anterior planning target volume margin was 0.57 cm. The average maximum exposure rate was measured to be 2.4 ± 1.1 mR/h, and average measured dose to a spouse was 0.99 ± 1.0 mSv. The calculated exposure rates and spousal doses using preimplantation computed tomography scan data overestimated those measured. Average measured family member dose (excluding spouses) was 0.20 ± 0.58 mSv. Conclusions: Based on measured and calculated spousal doses, a permanent breast seed implant using 103Pd is safe for the public. However, it is recommended that extra precautions in the way of a breast patch be used when patients with an implant will be in the vicinity of toddlers or pregnant women

  20. Essure Permanent Birth Control

    ... Prosthetics Essure Permanent Birth Control Essure Permanent Birth Control Share Tweet Linkedin Pin it More sharing options ... the Essure System Essure is a permanent birth control method for women (female sterilization). Implantation of Essure ...

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

    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

  2. Binding cells of 125I-iodoamphetamine in rat liver

    We recently reported that transrectal or intestinal portal scintigraphy with 123I-iodoamphetamine (IMP) could be a useful method for the non-invasive and quantitative evaluation of the portosystemic shunt in portal hypertension, but what cells in the liver trap IMP has not been clarified. This study was aimed at elucidating whether IMP was extracted by parenchymal cells, sinusoidal endothelial cells, Kupffer cells or fat storing cells. Each type of liver cell was isolated from rats and cultured. The cells were incubated with 125I-IMP and the radioactivity of the lysate was determined. Nonspecific binding was assessed in the presence of an excess of unlabeled IMP, and specific binding was determined by subtracting the nonspecific from total binding. Specific binding observed in parenchymal cells, endothelial cells and Kupffer cells was 70.2±0.4, 4.2±1.4 and 2.3±0.8 pmol/well, respectively, but no specific binding was observed in fat storing cells. The binding in parenchymal cells was much higher than that in endothelial cells or Kupffer cells (p<0.005). In addition, the binding to parenchymal cells reached equilibrium within 20 min and was not saturable over the concentration range tested (0.5-10 μM). These findings indicate that IMP is mostly extracted by parenchymal cells in the liver. (author)

  3. Novel Injectable Interpenetrating Polymer Network as a Semi-Permanent Injectable Implant for Soft Tissue Augmentation

    Leung, Joanne C.

    2015-01-01

    Injectable fillers have been widely used for soft tissue augmentation in cosmetic procedures, as well as minimally invasive treatment for medical conditions such as urinary and fecal incontinence, vesicoureteral reflux and vocal cord repair. The market for injectable fillers is a multibillion dollar industry worldwide, and each FDA-approved injectable filler has its own drawbacks, namely, lack of durability for temporary fillers, and difficulty in injection for semi-permanent to permanent...

  4. 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.

    Saito, Shunsuke; Fleischer, Bernhard; Mae, 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

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

    [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.

  6. 125I-LSD: a high sensitivity ligand for serotonin receptors

    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 γ-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.)

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

    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

  8. Influence of glucose and urea on 125I transport across an anion exchange paper membrane

    In order to study the influence of glucose and urea on the 125I transport across an anion exchange paper membrane, the transmembrane potential, the fluxes, and the concentrations of 125I, glucose and urea within the membrane were measured in the Na125I concentration-cell system containing glucose or urea. Glucose and urea increased the membrane/solution distribution of the iodide ion, but scarcely affected the diffusion process of iodide ion within the membrane

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

    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)

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

    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)

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

    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

  12. Reutilization of 125I-UdR during growth of a solid mammary carcinoma: Implications for the 125I-UdR loss technique

    Reutilization of thymidine (TdR) and 5-iodo-2'-deoxyuridine (I-UdR) released by dying tumour cells as assayed in the syngeneic adenocarcinoma EO 771 by injecting heat killed, labelled tumour cells into tumours. 3H and 125I liberation from labelled breakdown products was measured in tumours of various sizes without or with separation of tumours into viable and necrotic portions. Internal reutilization of 3H-TdR was considerably greater than that of 125I-UdR. 125I-UdR released by dying tumour cells was reutilized at about 10%. There was no significant increase in 125I-UdR reutilization during tumour growth. It is concluded that measurements of radioactivity loss by the 125I-UdR technique can result in underestimating the real cell loss depending on the amount of internal reutilization by the tumours investigated. Compared with 3H-TdR 125I-UdR is the tracer of choice for long term studies of cell loss. (orig.)

  13. [Apixaban in the treatment of venous thrombosis associated with permanent pacemaker implantation].

    Carrizo, Sebastián; Figueroa, Jorge A; Vivero, Alejandro

    2015-01-01

    Venous thromboembolism is the third vascular disease in morbidity and mortality. The new oral anticoagulants are presented as an effective and safe alternative to conventional antithrombotic therapy. Apixaban has been recently approved to use for the treatment of deep vein thrombosis. A case of an elderly patient, with high risk of bleeding, a history of cancer, and recent pacemaker implant, who consulted for superficial venous thrombosis of the ipsilateral arm to the implant, which was successfully treated with apixaban is here presented. PMID:26707667

  14. 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

    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.

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

    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).

  16. Comparative study on biodistribution of domestic and imported 125I-β-CIT

    Objective: To characterize the kinetics and biodistribution of a domestically synthesized 125I-2β-carbomethoxy-3β-4-iodopheny1tropane (β-CIT ) and to compare it with that of 125I-β-CIT imported from RBI company. Methods: 1)The biodistribution of domestic and RBI company produced 125I-β-CIT in KM mice. Twenty groups of mice (group of 5) were injected into the tail vein with either one of 125I-β-CIT products. Each group of both products was killed at 5,15,30 and 45 min, and 1, 2, 4, 6, 8 and 24 h. 2)Autoradiography was performed on the brain of SD rats at 2 h after injection. Results: Domestic 125I-β-CIT was primarily uptaked in the striatum, also in areas rich in 5-HTT such as the brain stem, frontal cortex, parietal cortex, temporal cortex, occipital cortex and hippocampus. Striatal uptake peaked at 2 h postinjection of 125I-β-CIT. The ratio of specific to nonspecific binding in striatum peaked at 6 h. The highest radioactivity was in the lungs and the less radioactivity was in the liver, kidney, spleen and intestine. Autoradiography confirmed that 125I-β-CIT primarily bound to striatum and lower room temperature significantly reduced the binding of the agent. Conclusion: The domestic 125I-β-CIT binds primarily to dopamine transporters in the striatum in mice and rats and the maximum uptake is in the lungs

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

    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)

  18. Determination of the specific activity of carrier-free 125I preparations by neutron activation analysis

    Heydorn, Kaj

    Chemical methods are unsuitable for the determination of the specific activity of commerical125I preparations because of the unknown chemical state of the iodine in solutions more than a few weeks old.125I and127I were determined in samples from seven different manufacturers by instrumental neutron...

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

    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

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

    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)

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

    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

  2. Experimental and clinical treatment of bladder cancer with 125I-iododeoxyuridine

    Radionuclide can cause auger effect through disintegration low-energy electron (125I-iododeoxyuridine (125I-UdR) is an efficient carrier inducting 125I to cell nucleolus, it is incorporated into DNA specificity only in S-phase cells. A series of studies show that 125I can absorb more likely to tumor cells, instead of the normal cell division, thus effectively splitting radiotherapy of malignant lesions. As bladder is a natural lumen, it has a unique easy perfusion and observational. 125I-UdR can kill effiently and selectively the cells of bladder turnout, reducing markedly the ratio of its recurrence of surgical treatment of patients with bladder cancer, so as to improve the survival rate. It can be used as a surgical adjuvant treatment method, is expected to be a safe, efficient and less adverse reaction the new therapies for bladder cancer treatment. (authors)

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

    (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.)

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

    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)

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

    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...

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

    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

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

    Ana de Lourdes S de, Lira; Svio, Prado; Mnica Tirre, Arajo; Eduardo Franzotti, Sant' Anna; Antonio Carlos de Oliveira, Ruellas.

    2013-04-01

    Full Text Available OBJETIVO: verificar se o mini-implante no palato eficaz como ancoragem direta para distalizao dos molares superiores. MTODOS: foi utilizado um modelo em acrlico da arcada superior. Aps a confeco da canaleta na regio correspondente aos alvolos dentrios, os dentes em acrlico foram fixados [...] com cera #7, montado aparelho ortodntico com a tcnica Edgewise e inserido um mini-implante (SIN, So Paulo) no local correspondente rafe palatina. Foram colocados arco 0,19" x 0,25" e barra transpalatina, soldados na barra dois ganchos para reteno de dois elsticos em cadeia de dois elos, a uma carga de 150g/f de cada lado (Unitek), que se estenderam dos ganchos at o mini-implante. O modelo da maxila foi mergulhado 40 vezes em banheira e fotografado aps cada mergulho para observao da movimentao dentria. Os dados foram analisados pela anlise da varinia (ANOVA) e teste de Tukey. RESULTADOS: os molares deslocaram-se distalmente 3,1mm, em mdia, com inclinao distal entre 3 e 5mm. CONCLUES: a movimentao dos molares ocorreu pela inclinao distal, com leve rotao, 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, So 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.

  8. Sinus Node Dysfunction Requiring Permanent Pacemaker Implantation in a Young Adult with Klinefelter Syndrome

    Karagöz, Ahmet; Dikbaş, Oğuz; Teker, Erhan; Vural, Aslı; Günaydın, Zeki Yüksel; Bektaş, Osman

    2015-01-01

    Patient: Male, 22 Final Diagnosis: Sinus node dysfunction Symptoms: Bradycardia • lassitude Medication: — Clinical Procedure: Pacemaker implantation Specialty: Cardiology Objective: Unusual clinical course Background: Klinefelter syndrome is the most common genetic cause of male infertility and affects approximately 1 in 500 live births. Although accompanying cardiac disorder is not a specific feature of Klinefelter syndrome, rarely associated anomalies such as mitral valve prolapse, atrial s...

  9. Bone Marrow Derived Adult Stem Cell Implantation: A Possible Permanent Treatment Modality for Type 2 Diabetics

    R.S. KAHLON; M.K. Manchanda; P. KANWAL

    2011-01-01

    Introduction: Diabetes is one of the most prevalent chronic disease that exists in the world. Type 2Diabetes is the predominant type of diabetes. Management is basically limited to exercise, diet and oralhypoglycemic drugs before insulin therapy has to be instituted. But bone marrow derived stem cellimplantation into the islets has shown very encouraging results for diabetics.Methods: Bone marrow derived stem cells when implanted in the pancreas leads to regeneration ofinsulin producing Beta ...

  10. 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

    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)

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

    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.)

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

    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

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

    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.)

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

    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

  15. (125I)Iodoazidococaine, a photoaffinity label for the haloperidol-sensitive sigma receptor

    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 μM 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

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

    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-2β-carbomethoxy-3β-(4-iodophenyl) tropane (125I-β-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-β-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-β-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

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

    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)

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

    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. 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. 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. 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

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

    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.

  20. Efficient radiolabeling of rutin with 125I and biodistribution study of radiolabeled rutin

    The purpose of the current research is to synthesize radiolabeled rutin for biodistribution study and SPECT/CT image of rutin. The optimized radiolabeling condition provided 125I-labeled rutin with 53.5 % of radiochemical yield. Most of orally administered 125I-labeled rutin was initially found in the stomach and small intestine and a portion of the product was then distributed in internal organs. While intravenously injected 125I-labeled rutin was accumulated in liver and then a large part of it was transferred to small intestine. The present results provided an efficient radiolabeling method of flavonoid glycoside as well as quantitative organ distribution of rutin. (author)

  1. Dosimetric analysis of 123I, 125I and 131I in thyroid follicle models

    Josefsson, Anders; Forssell-Aronsson, Eva

    2014-01-01

    Background Radioiodine is routinely used or proposed for diagnostic and therapeutic purposes: 123I, 125I and 131I for diagnostics and 125I and 131I for therapy. When radioiodine-labelled pharmaceuticals are administered to the body, radioiodide might be released into the circulation and taken up by the thyroid gland, which may then be an organ at risk. The aim of this study was to compare dosimetric properties for 123I, 125I and 131I in previously developed thyroid models for man, rat and mou...

  2. Metabolism of 125I-labelled trypsin in man: evidence of recirculation.

    Lake-Bakaar, G; Rubio, C E; McKavanagh, S; Potter, B. J.; Summerfield, J A

    1980-01-01

    125I-labelled human trypsin metabolism has been investigated in man. Three subjects received 125I-trypsin and 131I-albumin intravenously. Against a background secretin infusion (1 U/kg/h), trypsin decayed biexponentially from the serum with half-lives of 17.5, 21, and 24 minutes for the rapid disappearance phase and 520, 540, and 560 minutes for the slow phase. Between 13% and 38% of the 125I injected was recovered from duodenal juice aspirated continously over 300 minutes. In contrast, less ...

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

    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.)

  4. Improvement Of The Absolute Activity Determination Technique Of '125I In The Thyroid

    A method for absolute determination of the activity of a 125I source based on the counting rate values of the 27 keV photons and the 54 keV coincidence photo-peak is given in the literature. We had shown in previous works, that this method, within certain limitations, diminishes the geometry dependence of the activity determination for 125I sources and for measuring the uptake of 125I in human thyroid. In the present work we present a farther improvement of the accuracy of the absolute determination method

  5. OER and RBE for 125I and 192Ir at low dose rate on mammalian cells

    The oxygen enhancement ratio (OER) for 125I and 192Ir as well as the relative biological effectiveness (RBE) at low dose rates (40-80 cGy h-1) were determined for B16 melanoma cells in culture. The OER was found to be 2.1±0.03 for 125I and 2.7±0.04 for 192Ir. The RBE for 125I relative to 192Ir was determined as 1.8±0.03 under aerated conditions and as 2.4±0.03 under hypoxia. 18 refs.; 5 figs.; 1 table

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

    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

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

    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.)

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

    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...

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

    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)

  10. 125I-labeled crosslinking reagent that is hydrophilic, photoactivatable, and cleavable through an azo linkage.

    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...

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

    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

  12. 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

    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.)

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

    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, 100μg of ibuprofen as substrate and 100μg 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)

  14. Report of a minor 125I exposure in a research laboratory

    In routine thyroid scanning of personnel whose work involved the use of 125I in biological research, it was discovered that an individual who had been iodinating proteins periodically for over 6 months showed a high thyroid count rate. It was decided to monitor the individual's thyroid weekly and to curtail his work in the laboratory until the cause of the thyroid uptake could be determined. Initially the 125I concentration in his thyroid decreased as expected but a subsequent scan on the 21st day showed an 125I concentration even greater than the initial level despite his absence from the laboratory. However on monitoring his office space, it was discovered that a felt pen was grossly contaminated and that the individual habitually put the pen in his mouth during moments of cogitation. It was concluded that a contaminated glove had transferred some 125I to the pen during the course of the experiment. (U.K.)

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

    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.

  16. Expanso rpida da maxila ancorada em implantes: uma nova proposta para expanso ortopdica na dentadura permanente Rapid maxillary expansion anchored by implants: a new proposal to orthopedic expansion in the permanent dentition

    Daniela Gamba Garib

    2007-06-01

    Full Text Available OBJETIVO: este trabalho apresenta um mtodo para expanso ortopdica da maxila, na dentadura permanente, utilizando implantes como ancoragem. METODOLOGIA: detalharam-se os procedimentos cirrgicos e laboratoriais da confeco de um expansor com ancoragem dento-ssea em crnio seco humano. Dois implantes de titnio foram colocados na regio anterior do palato, e o parafuso Hyrax adaptado de modo que a expanso ancorou-se nos implantes e nos primeiros molares permanentes. RESULTADOS: o experimento laboratorial em crnio seco mostrou que o procedimento apresenta-se anatmica e operacionalmente vivel. Os implantes suportaram a fora gerada pela ativao do parafuso expansor, redundando na separao transversal das hemimaxilas. CONCLUSES: vislumbra-se que a expanso rpida da maxila ancorada em implantes (ERMAI poder potencializar a eficincia da expanso ortopdica, assim como reduzir o custo periodontal dos procedimentos convencionais de expanso. Futuros estudos clnicos so necessrios para testar essas hipteses.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.

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

    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

  18. Synthesis of 3-[125I]-iodo-phencyclidine for biological studies

    After verification of the biological activity of 3-iodo-phencyclidine (PCP) by binding studies to the N-methyl D-aspartate gated channel, 3-[125I]iodo-PCP was prepared by reaction of sodium iodide with a triazene precursor. The radiochemical yield was optimized and after HPLC purification, 3-[125I]iodo-PCP was obtained with a high radiochemical purity. (author)

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

    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.

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

    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

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

    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

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

    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

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

    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)

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

    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)

  5. Biodistribution analysis of 125I-albumin-IFN-alpha2b fusion protein in rats

    125I-albumin-IFN-alpha2b was prepared with the methods of Ch-T and purified with PD-10 column. The radiochemical purity was measured with TCA (trichloroacetic acid) precipitation. The antiviral activities of 125I-albumin-IFN-alpha2b and albumin-IFN-alpha2b were compared with WISH/VSV system in vitro. SD rats were injected with 125I-albumin-IFN-alpha2b subcutaneously and sacrificed at 0.5, 2, 6, 24, 48, 90, 180 and 300 h post-injection. Selected organs were dissected, weighed and their radioactivity was measured using γ-counter. The accumulated radioactivity in the tissues was calculated in terms of percentage of injected dose per gram organ (%ID·g-1). The labeling yield was 82.72%. The radiochemical purity of 125I-albumin-IFN-alpha2b was 95.53%, and its radioactivity was 0.26 MBq/μg. The antiviral bioactivities of albumin-IFN-alpha2b and 125I-albumin- IFN-alpha2b did not change. Biodistribution analysis of 125I-albumin-IFN-alpha2b in rats showed that concentrated 125I-albumin-IFN-alpha2b in blood reached maximum at 6 h post injection, and eliminated slowly. No specific accumulation was seen in other tissues. 125I-albumin-IFN-alpha2b could maintain in peripheral blood for a long time and it meant albumin-IFN-alpha2b would be an effective long-term interferon. (authors)

  6. 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

    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)

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

    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)

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

    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

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

    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.

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

    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)

  11. Apoptosis and p53 are not involved in the anti-tumor efficacy of (125)I-labeled monoclonal antibodies targeting the cell membrane. : Running title: 125I-RIT-induced cell death mechanisms

    Paillas, Salomé; Boudousq, Vincent; Piron, Bérengère; Kersual, Nathalie; Bardiès, Manuel; Chouin, Nicolas; Bascoul-Mollevi, Caroline; Arnaud, François-Xavier; PèLegrin, André; Navarro-Teulon, Isabelle; Pouget, Jean-Pierre

    2013-01-01

    INTRODUCTION: (125)I-labeled monoclonal antibodies ((125)I-mAbs) can efficiently treat small solid tumors. Here, we investigated the role of apoptosis, autophagy and mitotic catastrophe in (125)I-mAb toxicity in p53(-/-) and p53(+/+) cancer cells. METHODS: We exposed p53(-/-) and p53(+/+) HCT116 cells to increasing activities of internalizing (cytoplasmic location) anti-HER1 (125)I-mAbs, or non-internalizing (cell surface location) anti-CEA (125)I-mAbs. For each targeting model we established...

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

    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

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

    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

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

    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 γH2AX foci/cell and γH2AX 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 γH2AX foci per cell (t=8.0, P=0.05), and more γH2AX 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)

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

    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

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

    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

  17. Preparation of a 125I labelled [1,3H]imidazole: 2-n-butyl-4(5)-125I-iodo-5(4)-hydroxymethylene imidazole

    A method for the introduction of 125I in a substituted imidazole has been devised. 2-n-Butyl-4(5)-hydroxymethylene imidazole undergoes rapid and selective electrophilic substitution on the ring when treated with a halogenating agent such as, i.a., N-chlorosuccinimide. This reaction has been adapted to the preparation of 2-n-butyl-4(5)-125I-iodo-5(4)-hydroxymethylene imidazole by treatment of 2-n-butyl-4(5)-hydroxymethylene imidazole by chloramine-T in the presence of sodium iodide. The radiolabelled product purified and isolated by HPLC is obtained at a high specific activity (2200Ci/mmol) with good chemical and radiochemical yields (∼70%). (author)

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

    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

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

    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)

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

    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)

  1. Radioimmunoassay of salivary cyclosporine with use of 125I-labeled cyclosporine

    We prepared 125I-labeled cyclosporine (125I-CS) by modifying the procedure of Mahoney and Orf and characterized it with regards to maximal immunoreactivity (greater than 90%), trichloroacetic acid precipitability (greater than 90%), and stability (90% immunoreactive after five half-lives of 125I). For a particular preparation of 125I-CS, we estimated its immunoreaction concentration (50 pmol/L) and the equilibrium constant for its reaction with Sandoz polyclonal antiserum (K = 3.9 X 10(9) L/mol). By substituting 125I-CS as tracer in the Sandoz radioimmunoassay and by modifying other aspects of the assay, we developed a procedure that is sufficiently sensitive (0.34 micrograms/L) to allow measurement of trough (lowest inter-dose) cyclosporine concentrations in parotid saliva. Of 38 kidney-transplant patients, 35 had measurable concentrations in saliva (mean 8.3, SD 5.2 micrograms/L), and these correlated moderately with paired serum concentrations (r = 0.68, P less than 0.001). We believe that measurement of salivary cyclosporine may offer a simple way of estimating the free fraction of the drug in serum or plasma

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

    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

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

    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)

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

    ([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)

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

    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.

  6. Influence of acetylcholine on binding of 4-[125i]iododexetimide to muscarinic brain receptors

    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-[125I]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-[125I]iododexetimide in a dose-dependent manner. A concentration of 500 μM acetylcholine inhibited 50% of total specific 4-[125I]iododexetimide binding to synaptosomes when both substances were given simultaneously. An 800 μM acetylcholine solution reduced total specific 4-[125I]iododexetimide binding by about 35%, when acetylcholine was given 60 min after incubation of synaptosomes with 4-[125I]iododexetimide. Variations in the synaptic acetylcholine concentration might influence muscarinic cholinergic receptor imaging in vivo using 4-[123I]iododexetimide. Conversely, 4-[123I]iododexetimide might be an appropriate molecule to investigate alterations of acetylcholine release into the synaptic cleft in vivo using single photon emission computed tomography

  7. Preparation of 125I-cytarabine and its radiochemical evaluation. Model of radio-therapeutic agent

    Development of a new radiopharmaceutical for cancer imaging and therapy is described. The optimization of the labeling of thymidine analogous, cytarabine, with 125I is described. High radiochemical yield and purity ≥98% was obtained by reacting 50 μg cytarabine with 125I in the presence of iodogen as oxidizing agent and 0.5M phosphate buffer of pH 7 at 65 deg C for 30 minutes. Preliminary in-vivo study was done in non-tumor bearing mice. The results revealed that this new tracer, 125I-cytarabine, has a high affinity to be localized in tissues of high proliferation rate, e.g., bone marrow ≥10%, 60-minute post administration. Also, the labeled compound was cleared quickly from most of the body organs and concentrated in bladder ≥55%, 60-minute post administration. These findings suggest that 125I-cytarabine, allows imaging and treatment of cancer. 125I-cytarabine meets most of the requirements to be used as a successful diagnostic and therapeutic agent: it is a low molecular weight molecule that diffuses readily in tissues, it well not induce an antibody response, thereby leading itself to repeated injection or continuous infusion. (author)

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

    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

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

    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)

  10. 125I-iomazenil-benzodiazepine receptor binding during psychological stress in rats

    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)

  11. Radioimmunoassay for etorphine in horses with a 125I analog of etorphine

    To improve the sensitivity and specificity of screening for etorphine in horses, an 125I-labeled etorphine analog was synthesized and an antibody to etorphine was raised in rabbits. A radioimmunoassay (RIA) for etorphine was developed, using these reagents. Bound and free 125I-labeled etorphine was separated by a double-antibody method that reduced interference from materials associated with equine urine. The 125I-labeled etorphine binding was rarely greater than 250 pg of background etorphine equivalents/ml in raw urine and was 100 pg/ml in hydrolyzed urine. The 125I-RIA was capable of detecting etorphine equivalents in urine above these background values. Etorphine equivalents were detected in equine urine samples for about 7 days after 4 mares were dosed with 0.22 microgram of etorphine/kg of body weight, IV. The stability of etorphine in urine from these mares was evaluated. Urine from these dosed mares was held in constant -20 C storage, and aliquots were repeatedly frozen and thawed. When analyzed for etorphine equivalents using an 125I-RIA, etorphine and its metabolites in urine samples were stable for less than or equal to 38 days if continuously frozen and also were resistant to repeated freezing and thawing

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

    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

  13. Inulin-125I-tyramine, an improved residualizing label for studies on sites of catabolism of circulating proteins

    Residualizing labels for protein, such as dilactitol-125I-tyramine (125I-DLT) and cellobiitol-125I-tyramine, have been used to identify the tissue and cellular sites of catabolism of long-lived plasma proteins, such as albumin, immunoglobulins, and lipoproteins. The radioactive degradation products formed from labeled proteins are relatively large, hydrophilic, resistant to lysosomal hydrolases, and accumulate in lysosomes in the cells involved in degradation of the carrier protein. However, the gradual loss of the catabolites from cells (t1/2 approximately 2 days) has limited the usefulness of residualizing labels in studies on longer lived proteins. We describe here a higher molecular weight (Mr approximately 5000), more efficient residualizing glycoconjugate label, inulin-125I-tyramine (125I-InTn). Attachment of 125I-InTn had no effect on the plasma half-life or tissue sites of catabolism of asialofetuin, fetuin, or rat serum albumin in the rat. The half-life for hepatic retention of degradation products from 125I-InTn-labeled asialofetuin was 5 days, compared to 2.3 days for 125I-DLT-labeled asialofetuin. The whole body half-lives for radioactivity from 125I-InTn-, 125I-DLT-, and 125I-labeled rat serum albumin were 7.5, 4.3, and 2.2 days, respectively. The tissue distribution of degradation products from 125I-InTn-labeled proteins agreed with results of previous studies using 125I-DLT, except that a greater fraction of total degradation products was recovered in tissues. Kinetic analyses indicated that the average half-life for retention of 125I-InTn degradation products in tissues is approximately 5 days and suggested that in vivo there are both slow and rapid routes for release of degradation products from cells

  14. Polyclonal 111In-IgG, 125I-LDL and 125I-endothelin-1 accumulation in experimental arterial wall injury

    To test iodine-125 labelled low-density lipoprotein (125I-LDL), polyclonal indium-111 labelled immunoglobulin G(111In-IgG) and iodine-125 labelled endothelin-1 uptake in metabolically active atheromatous plaques after arterial wall injury, we performed balloon de-endothelialization of carotid arteries or abdominal aortas in 24 New Zealand male rabbits which were fed with a normal diet (n=14) or a hypercholesterolaemic diet (n=10) after surgery. Six weeks later the animals were injected with 200 μCi of 125I-LDL and/or with 100 μCi of 111In-IgG or with 9 μCi of 125I-endothelin-1. Forty-eight hours later the animals were sacrificed. Carotid arteries and aortas were removed, counted and fixed for autoradiography and light microscopic examination. Contralateral carotid arteries and thoracic aortas served as controls. Significant 111In-IgG uptake was observed in the injured arteries at autoradiography, with localization mainly in the healing edges, and at well counting. The percentage of the injected dose per gram (%D.inj/g) was 0.0188±0.06 versus 0.0059±0.003 in controls (P111In-IgG uptake between arteries with injury alone and those with active atheroma formation at the site of the injury. Significant 125I-LDL uptake was observed only when lipid deposition was present at light microscopy (%D.inj/g of 0.0024±0.0005 vs 0.0010±0.0003 in controls, P125I-endothelin-1 accumulation was observed in four of five injured aortas both at autoradiography, with diffuse localization, and at well couting (%D.inj/g of 0.0012±0.0004 in the abdominal aortas vs 0.0008±0.0003 in the thoracic aortas). Polyclonal IgG may accumulate in injured arteries without active atheroma formation. Inflammatory reaction at the site of the injury may cause 111In-IgG uptake independently of atheromatous plaque formation. LDL accumulation takes place only with active atheroma formation at the site of the injury. Use of labelled peptides such as endothelin-1 may provide further insight into the mechanisms of atheromatous plaque formation. (orig.)

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

    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.

  16. 99mTc-albumin can replace 125I-albumin to determine plasma volume repeatedly

    Bonfils, Peter K; Damgaard, Morten; Stokholm, Knud H; Nielsen, Steen L

    2012-01-01

    OBJECTIVE: Plasma volume assessment may be of importance in several disorders. The purpose of the present study was to compare the reliability of plasma volume measurements by technetium-labeled human serum albumin ((99m)Tc-HSA) with a simultaneously performed plasma volume determination with...... iodine-labeled human serum albumin ((125)I-HSA). MATERIALS AND METHODS: In 15 healthy volunteers, simultaneous plasma volume measurements with (99m)Tc-HSA and (125)I-HSA were performed after ½ hour in the supine position. Blood samples were obtained 10, 15, 20, and 30 minutes after the injection for...... accurate retropolation from the plasma counts to time zero to correct for leakage of the isotopes from the circulation. RESULTS: The mean difference (bias) between plasma volume measured with (125)I-albumin and (99m)Tc-albumin was 8 ml (0.1 ml/kg) with limits of agreement (bias ±1.96 SD) ranging from -181...

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

    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

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

    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 μCi/μg. 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.)

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

    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

  20. Double-strand breaks from 125I incorporated in the DNA and cell death

    Track structure calculations of the local energy deposition by electrons emitted during the decay of 125I are used to demonstrate that the range of high energy deposition is small (125I is incorporated into the DNA of synchronized CHO cells during a pulse and decays are allowed to accumulate a given time after the incorporation is described. Here it is shown that damage from 125I decays in newly replicated DNA (cells frozen for decay accumulation within 1 h after labelling) are relatively non-toxic whereas decays in mature DNA (cells frozen 5 h after labelling) are highly lethal. It is suggested that during DNA maturation the labelled DNA becomes associated with (or reorganized into) a radiosensitive nuclear structure and that damage to this structure is the primary cause of radiation-induced cell death. (Author)

  1. Distribution and disappearance of exogenous (/sup 125/I) big renin in the newborn puppy

    Siegel, S.R.; Parkhill, T.

    1983-05-01

    The distribution and metabolism of infused exogenous (/sup 125/I) inactive plasma big renin, molecular weight 56,000 was studied in five newborn puppies. The animals were sacrificed and the organs removed and studied by chromatography, along with periodic blood samples taken during the 120-min study, for evidence of conversion of high-molecular-weight renin to low-molecular-weight renin. The decay curve suggested an initial rapid distribution (alpha) phase followed by a slower elimination (beta) phase. The liver, kidneys, and lungs had the highest % of (/sup 125/I)-big renin at the termination of the study. There was no chromatographic evidence of a change in molecular weight of the (125I)-big renin. These data show that big renin has a two-compartment disappearance curve and that there is no evidence of conversion of high-molecular-weight renin to low-molecular-weight renin systemically or in the tissues of the newborn canine puppy.

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

    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: 40μg daunorubicin, 30μg 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.

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

    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

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

    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)

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

    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

  6. DNA strand breaks induced by 125I in cultured human kidney cells and their repair

    125I was incorporated into the DNA of cultured human kidney cells. In intact cells, 4 single-strand breaks per decay were measured. Two SSBs per decay were found in isolated DNA. The numbers of double-strand breaks per decay in two experiments ranged from 1.4 to 2.7 depending on two different constants used in the calculations. A detailed microdosimetric analysis will be necessary to establish relationships between eV absorbed in DNA after 125I-decay and numbers of induced strand breaks. By incubation of the cells after exposure repair of SSBs could be demonstrated. This was not the case for DSBs

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

    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

  8. Labeling of Annexin V with 125I and its biodistribution in mice

    Annexin V is labeled with 125I by using Iodogen method and the biodistribution of which in mice is investigated. The labeling yield of 125I-Annexin V is 94.9% and its radio-chemical purity is over 99% after purification. The radioactivity uptake is the highest in kidney, followed in order by blood, liver, heart, lung and spleen; no uptake in brain; the lower in muscle and bone; The uptake of the selected tissues is decreased rapidly at 1 hour after injection except blood. The results show that it is a excellent imaging agent for diagnoses. (authors)

  9. p-( sup 125 I)iodoclonidine is a partial agonist at the alpha 2-adrenergic receptor

    Gerhardt, M.A.; Wade, S.M.; Neubig, R.R. (Univ. of Michigan Medical School, Ann Arbor (USA))

    1990-08-01

    The binding properties of p-(125I)iodoclonidine (( 125I)PIC) to human platelet membranes and the functional characteristics of PIC are reported. (125I)PIC bound rapidly and reversibly to platelet membranes, with a first-order association rate constant (kon) at room temperature of 8.0 +/- 2.7 x 10(6) M-1 sec-1 and a dissociation rate constant (koff) of 2.0 +/- 0.8 x 10(-3) sec-1. Scatchard plots of specific (125I)PIC binding (0.1-5 nM) were linear, with a Kd of 1.2 +/- 0.1 nM. (125I)PIC bound to the same number of high affinity sites as the alpha 2-adrenergic receptor (alpha 2-AR) full agonist (3H) bromoxidine (UK14,304), which represented approximately 40% of the sites bound by the antagonist (3H)yohimbine. Guanosine 5'-(beta, gamma-imido)triphosphate greatly reduced the amount of (125I)PIC bound (greater than 80%), without changing the Kd of the residual binding. In competition experiments, the alpha 2-AR-selective ligands yohimbine, bromoxidine, oxymetazoline, clonidine, p-aminoclonidine, (-)-epinephrine, and idazoxan all had Ki values in the low nanomolar range, whereas prazosin, propranolol, and serotonin yielded Ki values in the micromolar range. Epinephrine competition for (125I)PIC binding was stereoselective. Competition for (3H)bromoxidine binding by PIC gave a Ki of 1.0 nM (nH = 1.0), whereas competition for (3H)yohimbine could be resolved into high and low affinity components, with Ki values of 3.7 and 84 nM, respectively. PIC had minimal agonist activity in inhibiting adenylate cyclase in platelet membranes, but it potentiated platelet aggregation induced by ADP with an EC50 of 1.5 microM. PIC also inhibited epinephrine-induced aggregation, with an IC50 of 5.1 microM. Thus, PIC behaves as a partial agonist in a human platelet aggregation assay. (125I)PIC binds to the alpha 2B-AR in NG-10815 cell membranes with a Kd of 0.5 +/- 0.1 nM.

  10. p-[125I]iodoclonidine is a partial agonist at the alpha 2-adrenergic receptor

    The binding properties of p-[125I]iodoclonidine [( 125I]PIC) to human platelet membranes and the functional characteristics of PIC are reported. [125I]PIC bound rapidly and reversibly to platelet membranes, with a first-order association rate constant (kon) at room temperature of 8.0 +/- 2.7 x 10(6) M-1 sec-1 and a dissociation rate constant (koff) of 2.0 +/- 0.8 x 10(-3) sec-1. Scatchard plots of specific [125I]PIC binding (0.1-5 nM) were linear, with a Kd of 1.2 +/- 0.1 nM. [125I]PIC bound to the same number of high affinity sites as the alpha 2-adrenergic receptor (alpha 2-AR) full agonist [3H] bromoxidine (UK14,304), which represented approximately 40% of the sites bound by the antagonist [3H]yohimbine. Guanosine 5'-(beta, gamma-imido)triphosphate greatly reduced the amount of [125I]PIC bound (greater than 80%), without changing the Kd of the residual binding. In competition experiments, the alpha 2-AR-selective ligands yohimbine, bromoxidine, oxymetazoline, clonidine, p-aminoclonidine, (-)-epinephrine, and idazoxan all had Ki values in the low nanomolar range, whereas prazosin, propranolol, and serotonin yielded Ki values in the micromolar range. Epinephrine competition for [125I]PIC binding was stereoselective. Competition for [3H]bromoxidine binding by PIC gave a Ki of 1.0 nM (nH = 1.0), whereas competition for [3H]yohimbine could be resolved into high and low affinity components, with Ki values of 3.7 and 84 nM, respectively. PIC had minimal agonist activity in inhibiting adenylate cyclase in platelet membranes, but it potentiated platelet aggregation induced by ADP with an EC50 of 1.5 microM. PIC also inhibited epinephrine-induced aggregation, with an IC50 of 5.1 microM. Thus, PIC behaves as a partial agonist in a human platelet aggregation assay. [125I]PIC binds to the alpha 2B-AR in NG-10815 cell membranes with a Kd of 0.5 +/- 0.1 nM

  11. The assay of Met-enkephalin aminopeptidase with [125I]Met-enkephalin

    Presented here are procedural modifications which permit the utilization of 125I-labeled Met-enkephalin as substrate in the assay of rat brain enkephalin aminopeptidase. The hydrolysis of enkephalin is monitored by the release of [125I]tyrosine separated on Porapak Q. The release of tyrosine is proportionate with both increasing time and tissue concentration. The estimated Ksub(m) is near 10-4M and the enzyme activity can be inhibited more than 95% with puromycin. The majority of the enzyme activity remains in the 100000xg supernatant following differential centrifugation. (Auth.)

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

    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.)

  13. Synthesis of 123I- and 125I-labelled 5-iodo-6-nitroquipazine

    The syntheses of the potent and selective serotonin reuptake complex radioligands [123I]- and 125I]5-iodo-6-nitroquipazine (5-iodo-6-nitro-2-piperazinylquinoline) are reported. A seven step synthetic sequence provided the BOC-protected 5-tributyltin-6-nitroquipazine precursor for radioiodination. End of sy nthesis radioiodination yields of ∼ 40% for 123I and ∼ 60% for 125I were achieved resulting in labelled products with high specific activities (> 4000 and > 2000 Ci/mmol, respectively) and radiochemical purities (> 98%). (author)

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

    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.

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

    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)

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

    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

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

    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

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

    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

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

    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

  20. Morbimortalidad de la endocarditis infecciosa asociada a dispositivos electrnicos implantables permanentes / Morbimortality of infective endocarditis associated with permanent cardiovascular implantable electronic devices

    Gabriel, Prez-Baztarrica; Flavio, Salvaggio; Norberto, Blanco; Hctor, Mazzetti; Ricardo, Levin; Alejandro, Botbol; Rafael, Porcile.

    2013-12-01

    Full Text Available La endocarditis infecciosa (EI) asociada a dispositivos electrnicos implantables permanentes (DEIP) es una complicacin de baja frecuencia pero alta mortalidad sin el tratamiento adecuado. El avance sobre el conocimiento de esta patologa y el desarrollo de estrategias teraputicas como el diagnst [...] ico precoz, manejo de antibiticos, tcnicas de extraccin, entre otras, han mejorado el pronstico 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 diagnstico de EI asociada a DEIP. Se analizaron caractersticas basales, diagnsticas, teraputicas, evolucin intrahospitalaria y alejada. Se incluyeron 26 casos atendidos en nuestro hospital, 23 de los cuales fueron remitidos desde otros centros para su diagnstico y tratamiento. La edad promedio fue de 67,5 aos. Todos los pacientes recibieron antibiticos durante seis semanas y se les retir el sistema en forma completa; en el 95% de los pacientes por va percutnea y en 2 pacientes se requiri estereotoma mediana, atriotoma y colocacin de marcapasos epicardaco. 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 complicacin. Como conclusin la EI es un cuadro grave que presenta una morbilidad elevada con estadas hospitalarias prolongadas, pero la mortalidad es baja. La explicacin podra estar en las tcnicas percutneas, experiencia, extraccin 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.

  1. Study on the thyroid function of thoroughbred horses by means of 'in vitro' 125I-T3 modified and 125I-T4 tests

    Sera of 71 animals, divided in groups of males and females, in repose and after activity were studied. The method to establish the percentage of the 125I-lyothyronine retention in resin (Test 125I-T3 or T3) was modified by the use of 0.2 ml of serum on the resin column, after addition of the marked hormone. This modification served to prove that thoroughbred equines show binding of the I-lyothyronine to the serum four times reduced, indicating, therefore, that these animals have four times more ligation sites of triidothyronin saturation in the serum, when compared with the results obtained from human beings. The variance analysis applied to the T3 Test showed no significant results at the 95% level as regards to activity. For the 71 animals, the author has found an average of 50.30% of the 125I-Lyothyronine in resin retention, being the confidence interval for this group between 48.75% and 51.85% to a 95% confidence coefficient. Evaluating the results of the T4 Test by means of the variance analysis, we noticed that the male and female groups in repose differed statistically from the groups after activity to a 95% confidence coefficient. The author has grouped the results of the T4 Test of 32 equines, 18 males and 14 females, in repose, obtaining an average of 0.61 mcg and 0.51 mcg and 0.71 mcg T4/100 ml as confidence interval to a 95% confidence coefficient. We have listed 39 results of T4 Test, being 23 males and 61 Females, after activity, obtaining an average of 2.01 mcg of thyroxin by 100 ml of serum and 1.72 mcg and 2.30 T4/100 ml as confidence interval to a 95% confidence coefficient

  2. 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

    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)

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

    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

  4. Research on apoptosis of MCF-7 cells induced by continuous irradiation by 125I seeds

    Objective: To detect the apoptotic rate and the changes of expressions of Bcl-2 and Bax in MCF-7 cells continuously irradiated with low dose rate γ-rays from 125I seeds. Methods: MCF-7 cells were exposed to the radiation for 72 hours from model 6711 125I seeds with an apparent activity of 27.75 MBq. Then, RT-PCR and Western blot were used to detect the expressions of Bcl-2 and Bax in MCF-7 cells. FCM and Annexin V assay were performed to detect the apoptotic rate of MCF-7 cells. Results: Higher expression of Bcl-2 and lower expression of Bax in irradiated MCF-7 cells compared to those in the control cells were detected. FCM and Annexin V assay showed a significant increase of apoptotic rate in MCF-7 cells after continuous irradiation by 125I seeds. Conclusion: Continuous irradiation with 125I increases the apoptotic rate of MCF-7 cells, and this increase may be induced by decreased ratio of Bcl-2/Bax. (authors)

  5. Effects of age and sex on 125I-β-CIT binding to DAT

    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

  6. Preparation and bio-distribution of 125I-fullerene pyrrolidine benzoyl nitrogen mustard

    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)

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

    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.)

  8. Absolute intensity of internal bremsstrahlung from the electron capture decay of 125I

    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

  9. Development of in vivo Thyroid 123I, 125I, 131I monitoring method with imaging plate

    123I, 125I and 131I, which accumulate in the thyroid, are used unsealed in medical practice as the useful nuclide but internal contamination by these radioiodines can therefore occur in radiation workers, medical workers and patients' family. Moreover, the radioiodines can also induce the thyroid dysfunction of the public due to the nuclear accident like Chernobyl one. This report describes authors' investigation of the development of in vivo thyroid 123I-, 125I-, and 131I-monitoring method with the imaging plate (IP). A sheet of 20 cm x 10 cm IP was wound around the neck-thyroid phantom where the thyroid phantom was filled with the 123I, 125I or 131I solution and effects of the neck diameter, thyroid volume and tissue thickness were examined on the counting efficiency, error and detection limit using the Bio-image Analyzer System (BAS 2500) for measurement. As an example, the detection limit of 125I was 20 Bq, which was as low as 7/100,000 of its annual limit of intake (300 kBq), suggesting that this method can be practically useful. More precise image analysis and its technology are under investigation. (N.I.)

  10. Variation in 125I-insulin absorption and blood glucose concentration

    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...

  11. Labeling of peptides by Na125I-IODO-GENtm system

    Veselá, Iva; Elbert, Tomáš

    Praha : Institut of organic Chemistry and Biochemistry ASCR, 2009 - (Slaninová, J.), s. 136-138 ISBN 978-80-86241-31-9. - (Collection Symposium Series. 11). [Biologically Active Peptides. Conference /11./. Praha (CZ), 22.04.2009-24.04.2009] Institutional research plan: CEZ:AV0Z40550506 Keywords : radioiodination * 125-I * peptides * IODO-GEN Subject RIV: CC - Organic Chemistry

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

    Almqvist, H.; Wefel, J.S.; Lagerloef, F.E.; Ekstrand, J.; Henrikson, C.O.

    1988-09-01

    Radiation from a /sup 125/I 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 /sup 125/I 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 /sup 125/I 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 /sup 125/I absorptiometry can be used for continuous non-destructive measurements of root hard-tissue demineralization in vitro.

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

    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

  14. Apparent volumes of distribution of 125I-lothalamate and inulin in chickens (38781)

    The suitability of utilizing 125I-iothalamate to estimate the volume of extracellular fluid was assessed in ureterally ligated chickens. Subsequent to intravenous administration the movement of labeled iothalamate from the plasma compartment follows closed two-compartment kinetics and equilibration between vascular and extravascular phases is attained in about 20 minutes. The volume of distribution of 125I-iothalamate prior to and following the infusion of 0.15 M NaCl (equal to 15 percent of the estimated ECFV) averaged 23.6 +- 0.61 and 28.4 +- 0.22 percent of the body weight, respectively. The observed postsaline labeled iothalamate space did not differ statistically from the expected value. When administered simultaneously inulin penetrates into an apparent volume that is 75 percent of the labeled iothalamate space after 60 minutes. The content of 125I-iothalamate is relatively high in liver and kidney tissue and suggests that these are major sites where removal of the indicator from plasma occur. It is suggested that 125I-iothalamate, under appropriate conditions, could be used to measure the plasma volume and the extravascular fluid with which plasma is in rapid diffusion equilibrium. (U.S.)

  15. Dopamine transport sites selectively labeled by a novel photoaffinity probe: 125I-DEEP

    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

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

    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

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

    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 μm; coatings were 0.01 to 0.02 μm. 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

  18. Biological activity of [127I] and [125I] estradiol analogs in vitro and in vivo

    In order to develop a means by which the receptor status of breast cancers could be studied in vivo, 127I and 125I analogs of estrogens were synthesized and their abilities to bind to uterine receptors, to translocate these receptors to the nucleus, and to bind in vivo to mammary tumors in rats were studied. 6-[127I]-Iodoestra-1,3,5(10),6-tetraene-3,17 β-diol (2a), 16 β-[127I]-iodoestra-1,3,5(10)-triene-3,17 β-diol (1) and 16 chi-[127I]-iodoestra-1,3,5(10)-triene-3,17 β-diol (3a) were capable of binding to the 8S cytosol receptor, translocating the cytosol receptor to the nucleus, in vitro, and increasing uterine weight in vivo. 16chi[125I]-Iodoestradiol (3b) was found to bind to high affinity 8S cytosol receptors but 6-[125I]-iodoestratetraene (2b) appeared to bind only non-specifically to macromolecules sedimenting in the 4S region. When these compounds (2b) and (3b) labeled with 125I, were administered to rats with DMBA-induced mammary tumors, the radioactivity as determined by imaging techniques was noted primarily in the liver and intestines. However, some rat tumors appeared to concentrate compound (2b). In at least one such tumor, the iodinated estrogen (2b) was bound non-specifically to 4S proteins. (author)

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

    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)

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

    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.

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

    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 lkg-1 dry weight (dw) for suspended sediment, 1362 2.9 lkg-1 dw for particles in sediment traps and 132/x6 lkg-1 dw for bottom sediment. Concentrations in fish ranged from = 8 to 184 Bqg-1 dw, whereas concentration factors from water to fish ranged from 20 to 390 lkg-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

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

    Poon, A.M.S.; Liu, Z.M.; Tang, F.; Pang, S.F. (Univ. of Hong Kong (China))

    1994-03-01

    The immunosuppressive effect of chronic glucocorticoid treatment on 2[[sup 125]I] 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[[sup 125]I] 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[[sup 125]I] iodomelatonin binding sites was decreased while the affinity was not affected. The modulation of the thymic 2[[sup 125]I] 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.

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

    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)

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

    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

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

    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

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

    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

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

    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.

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

    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

  9. Dosimetric analysis of 123I, 125I and 131I in thyroid follicle models

    2014-01-01

    Background Radioiodine is routinely used or proposed for diagnostic and therapeutic purposes: 123I, 125I and 131I for diagnostics and 125I and 131I for therapy. When radioiodine-labelled pharmaceuticals are administered to the body, radioiodide might be released into the circulation and taken up by the thyroid gland, which may then be an organ at risk. The aim of this study was to compare dosimetric properties for 123I, 125I and 131I in previously developed thyroid models for man, rat and mouse. Methods Dosimetric calculations were performed using the Monte Carlo code MCNPX 2.6.0 and nuclear decay data from ICRP 107. Only the non-radiative transitions in the decays were considered. The S value was determined for the cell nuclei in species-specific thyroid follicle models for mouse, rat and man for different spatial distributions of radioiodine. Results For the species-specific single follicle models with radioiodine homogeneously within the follicle lumen, the highest S value came from 131I, with the largest contribution from the β particles. When radioiodine was homogeneously distributed within the follicle cells or the follicle cell nucleus, the highest contribution originated from 125I, about two times higher than 123I, with the largest contribution from the Auger electrons. The mean absorbed dose calculated for our human thyroid multiple follicle model, assuming homogenous distribution of for 123I, 125I, or 131I within the follicle lumens and follicle cells, was 9%, 18% and 4% higher, respectively, compared with the mean absorbed dose according to Medical Internal Radiation Dose (MIRD) formalism and nuclear decay data. When radioiodine was homogeneously distributed in the follicle lumens, our calculations gave up to 90% lower mean absorbed dose for 125I compared to MIRD (20% lower for 123I, and 2% lower for 131I). Conclusions This study clearly demonstrates the importance of using more detailed dosimetric methods and models than MIRD formalism for radioiodine, especially 123I and 125I, in the thyroid. For radioiodine homogeneously distributed in the follicle lumens our calculations for the human multiple follicle models gave up to 90% lower mean absorbed dose compared with MIRD formalism. PMID:25006543

  10. Improved separation of 3H and 125I spectra in liquid scintillation counting by doping with thallium and lead

    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)

  11. Long-Term Efficacy and Toxicity of Low-Dose-Rate 125I Prostate Brachytherapy as Monotherapy in Low-, Intermediate-, and High-Risk Prostate Cancer

    Purpose/Objectives: To report long-term efficacy and toxicity for a single-institution cohort of patients treated with low-dose-rate prostate brachytherapy permanent implant (PI) monotherapy. Methods and Materials: From 1996 to 2007, 1989 patients with low-risk (61.3%), intermediate-risk (29.8%), high-intermediate-risk (4.5%), and high-risk prostate cancer (4.4%) were treated with PI and followed up prospectively in a registry. All patients were treated with 125I monotherapy to 144 Gy. Late toxicity was coded retrospectively according to a modified Common Terminology Criteria for Adverse Events 4.0 scale. The rates of biochemical relapse-free survival (bRFS), distant metastasis-free survival (DMFS), overall survival (OS), and prostate cancer–specific mortality (PCSM) were calculated. We identified factors associated with late grade ≥3 genitourinary (GU) and gastrointestinal (GI) toxicity, bRFS, DMFS, OS, PCSM, and incontinence. Results: The median age of the patients was 67 years, and the median overall and prostate-specific antigen follow-up times were 6.8 years and 5.8 years, respectively. The overall 5-year rates for bRFS, DMFS, OS, and PCSM were 91.9%, 97.8%, 93.7%, and 0.71%, respectively. The 10-year rates were 81.5%, 91.5%, 76.1%, and 2.5%, respectively. The overall rates of late grade ≥3 GU and GI toxicity were 7.6% and 0.8%, respectively. On multivariable analysis, age and prostate length were significantly associated with increased risk of late grade ≥3 GU toxicity. The risk of incontinence was highly correlated with both pre-PI and post-PI transurethral resection of the prostate. Conclusions: Prostate brachytherapy as monotherapy is an effective treatment for low-risk and low-intermediate-risk prostate cancer and appears promising as a treatment for high-intermediate-risk and high-risk prostate cancer. Significant long-term toxicities are rare when brachytherapy is performed as monotherapy

  12. Long-Term Efficacy and Toxicity of Low-Dose-Rate {sup 125}I Prostate Brachytherapy as Monotherapy in Low-, Intermediate-, and High-Risk Prostate Cancer

    Kittel, Jeffrey A.; Reddy, Chandana A.; Smith, Kristin L.; Stephans, Kevin L.; Tendulkar, Rahul D. [Department of Radiation Oncology, Cleveland Clinic Taussig Cancer Institute, Cleveland, Ohio (United States); Ulchaker, James; Angermeier, Kenneth; Campbell, Steven; Stephenson, Andrew; Klein, Eric A. [Department of Urology, Cleveland Clinic Glickman Urological and Kidney Institute, Cleveland, Ohio (United States); Wilkinson, D. Allan [Department of Radiation Oncology, Cleveland Clinic Taussig Cancer Institute, Cleveland, Ohio (United States); Ciezki, Jay P., E-mail: ciezkij@ccf.org [Department of Radiation Oncology, Cleveland Clinic Taussig Cancer Institute, Cleveland, Ohio (United States)

    2015-07-15

    Purpose/Objectives: To report long-term efficacy and toxicity for a single-institution cohort of patients treated with low-dose-rate prostate brachytherapy permanent implant (PI) monotherapy. Methods and Materials: From 1996 to 2007, 1989 patients with low-risk (61.3%), intermediate-risk (29.8%), high-intermediate-risk (4.5%), and high-risk prostate cancer (4.4%) were treated with PI and followed up prospectively in a registry. All patients were treated with {sup 125}I monotherapy to 144 Gy. Late toxicity was coded retrospectively according to a modified Common Terminology Criteria for Adverse Events 4.0 scale. The rates of biochemical relapse-free survival (bRFS), distant metastasis-free survival (DMFS), overall survival (OS), and prostate cancer–specific mortality (PCSM) were calculated. We identified factors associated with late grade ≥3 genitourinary (GU) and gastrointestinal (GI) toxicity, bRFS, DMFS, OS, PCSM, and incontinence. Results: The median age of the patients was 67 years, and the median overall and prostate-specific antigen follow-up times were 6.8 years and 5.8 years, respectively. The overall 5-year rates for bRFS, DMFS, OS, and PCSM were 91.9%, 97.8%, 93.7%, and 0.71%, respectively. The 10-year rates were 81.5%, 91.5%, 76.1%, and 2.5%, respectively. The overall rates of late grade ≥3 GU and GI toxicity were 7.6% and 0.8%, respectively. On multivariable analysis, age and prostate length were significantly associated with increased risk of late grade ≥3 GU toxicity. The risk of incontinence was highly correlated with both pre-PI and post-PI transurethral resection of the prostate. Conclusions: Prostate brachytherapy as monotherapy is an effective treatment for low-risk and low-intermediate-risk prostate cancer and appears promising as a treatment for high-intermediate-risk and high-risk prostate cancer. Significant long-term toxicities are rare when brachytherapy is performed as monotherapy.

  13. (/sup 125/I) radioiodinated metaraminol: A new platelet-specific labeling agent

    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.

  14. [125I]protein A: a tracer for general use in immunoassay

    An immunoassay method was developed in which 125I-labeled Protein A ([125I]PA) of high specific activity (100 Ci/mmole) and functional activity >= 85%) served as a general tracer. Antigen (or hapten) was immobilized by covalent binding to a solid bead support. Aliquots of the appropriate beads were incubated with antibody (either purified IgG fraction or whole antiserum), washed with buffer, then incubated with [125I]PA. The amount of [125I]PA bound to the antibody-coated beads was a measure of antibody binding. The ability of antigen (or hapten) in the fluid phase to inhibit the binding of antibody under optimal conditions, measured as inhibition of [125I]PA binding, served as the basis for quantification in the assay. The method was applied to 3 antigens (human chorionic gonadotropin (HCG), human immunoglobulin M (IgM) and goat immunoglobulin G (IgG)) and to methotrexate as an example of a hapten. Optimal assay conditions were developed and, in each case, picomole levels or less of the homologous ligand could be detected. Antibody specificity was determined by measuring the ability of compounds related to the antigen or hapten to act as inhibitors. Levels of HCG in urine from pregnant women and levels of IgM in normal human sera were determined by this method. The assay required only approximately 3 h to perform, gave accurate reproducible results, and was at least as sensitive as other available immunoassay methods (e.g. radioimmunoassay). (Auth.)

  15. Tyrosine A14[125I]monoiodoinsulin: preparation, biologic properties, and long-term stability

    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

  16. Anti-tumor effects of Egr-IFN ? gene therapy combined with 125I-UdR radionuclide therapy

    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)

  17. Studies on the distribution of 125I-labelled Hemorrhagic toxin from agkistrodon acutus (125I-AaT) in rabbits and its pharmacokinetic characters

    125I-AaT, prepared by oxidant-chloroamine T from the related venom of Agkistrodon Acutus, is given to a rabbit by intravenous injection, and then, the distribution of the toxin in the rabbit and its pharmacokinetic characters have been studied.The rabbit is killed five hours after the injection, and the radioactivity in each tissue calculated. The result indicates that the blood-brain barrier exist in the body, and large quantity of by-products of 125I-AaT metabolism is eliminated from urine by the kidney. For pharmacokinetics, the computer simulated curve demonstrates that the result conforms to the Two Compartment Model. The fast component half-life T1/2α is 3.15 mins. , the slow component half-life T1/2β is 165 mins. , and the biological half-life T1/2 is 75.2 mins.Vd33, Vt and Ve have been analyzed, and the author thinks preliminarily that there must have been a corresponding receptor to the toxin in the body

  18. Comparison of (/sup 125/I)HIPDm and (/sup 125/I)iodoantipyrine in quantifying regional cerebral blood flow in rats

    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.

  19. 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

    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)

  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

    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.)

  1. The tumor control probability model for transperineal permanent prostate brachytherapy and prostate-specific antigen failure free survival

    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.

  2. 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

    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.

  3. PSA bounce after {sup 125}I-brachytherapy for prostate cancer as a favorable prognosticator

    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.)

  4. Measured human thyroid 125I activities deriving from waste discharges in the Thames Valley area, UK

    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)

  5. Application of different 125I tracers in radioimmunoassays of estradiol-17?

    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)

  6. Determination of dosimetric characteristics of 125I-103Pd brachytherapy source with Monte-Carlo method

    According to dose parameters calculation formula of seed source recommended by AAPM TG43U1, 125I-103Pd seed source dose parameters calculation formula and a variety of radionuclides composite seed source of dose parameters calculation formula can be obtain. Dose rate constant, radial dose function and anisotropy function of 125I-103Pd composite seed source are calculated by Monte-Carlo method, Empiric equations are obtained for radial dose function and anisotropy function by curve fitting. Comparisons with the relative data recommend by AAPM are performed. For the single source, the deviation of dose rate constant is 0.959 (cGy·h-1·U-1), and with 0.6093% from the AAPM. (authors)

  7. Quantitative determination of islet cell surface antibodies using 125I-protein A

    A quantitative method to measure islet cell surface antibodies in human patients has been developed using 125I-protein A. Isolated, dispersed, viable rat islet cells prepared by collagenase digestion were fixed in 4% paraformaldehyde to allow storage for up to 7 wk at 4 degrees C. Human sera, heat inactivated and adsorbed with rat liver and kidney powder (100 mg/ml), were incubated with the fixed cells (50 x 10(3)) for 60 min at 37 degrees C. Thereafter the cells were washed and exposed to 5 x 10(5) cpm 125I-protein A, which binds to IgG attached to the cell surface. Assay precision (14%) and reproducibility (16%) were established by repeated analysis of pooled sera from healthy individuals and IDDM patients using pooled batches of islet cells. Using this method, islet cell surface antibodies were detected in 35% of insulin-dependent diabetic patients

  8. Immobilization of viral antigens on filter paper for a [125I] staphylococcal protein A immunoassay

    A new technique is described for the rapid detection and quantitation of herpes simplex virus (HSV) antigens and antiviral antibodies. It involves immobilization of HSV antigens on filter paper discs and subsequent analysis by 125I-labelled staphylococcal protein A (SPA) radioimmunoassay. A specially designed 96-well filtration device is employed which serves both as an incubation chamber and as a filtration manifold. It is rapid, simple, sensitive and specific, and requires only small volumes of antiserum and few target cells. The results may be readily and objectively quantitated. This technique permits the simultaneous assay of a large number of specimens in less than 1h. Its sensitivity is considerably greater than that of other currently used immunologic techniques, and it is amenable to automation. These characteristics suggest that this [125 I]SPA immunofiltration technique may be applicable to the rapid diagnosis of viral infections. (Auth.)

  9. Activity concentration of a solution of 125I: results of an international comparison

    Nineteen laboratories have taken part in an international comparison of activity measurement of a solution of 125I organized by the Bureau International des Poids et Mesures (BIPM). Eight methods have been used by the participants. The total range of the results is 6.4% (2.5% if an outlier is excluded). The unweighted mean value of the 19 results, evaluated from the experimental data communicated by the laboratories, is (1 427.6±4.4) Bq mg-1 at reference date. The uncertainty of the unweighted mean is 0.3% (1σ), and 1.3% for a single laboratory. Two of the values reported are rather distant from the other results, but no convincing reason has been found to exclude them. Six laboratories, two of them during the trial comparison, determined the half life of 125I and reported values between 59.3 d and 59.9 d. (orig.)

  10. Enzymatic iodination of salivary proteins by the 125I-lactoperoxidase system

    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)

  11. Synthesis and biological evaluation of 125I-erythropoietin as a potential radiopharmaceutical agent for tumours

    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 (125I-EPO. In mice with induced melanoma, only a residual fixation in the tumour was evident. Further studies are warranted on other tumoral cell lines to better understand the binding process and internalization into cells. Studies on EPO labeled with carbon-11 could be valuable, since there is a greater chance of preserving the biological activity of the protein using this method. (author)

  12. Histoautoradiography of central nervous system in rats with generalized tetanus due to 125I-toxin

    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.)

  13. Tissue localization of [125I]triiodothyronine in the periorbital area of mice: a microautoradiographic study

    A significant retention of [125I]triiodothyronine ([125I]T3] in the retrobulbar orbital area of mice has been previously shown. The present study was initiated to determine tissue and intracellular localization of the thyroid hormone in the above area which is concerned in human Graves' disease of the thyroid. In conclusion, after in vivo injection, the thyroid hormone rapidly penetrates the cells of fat glandular and muscular tissues in the orbital area. Intracellularly, the affinity of the hormone for the secretory vesicles, rough endoplasmic reticulum, mitochondria and nucleus suggest that T3 could play a role in secretory and metabolic functions of the tissues in the retrobulbar orbital area. (Author)

  14. Specific activity determination of 125I labelled prolactin by receptor and radioinmunological self-displacement methods

    It was studied the specific activity of 125i labelled prolactin by mean of self-displacement of the hormone in binding experiments, using radioimmunoassay or receptor technique. The results obtained immediately after the labelling were compared to those calculated from yield measurement through radiochromatography. The specific activity was determined by self-displacement in order to study its modification with the time elapsed after labelling. The change of specific activity with different labelling conditions and using RIA or receptor techniques for its determination was also studied. The S.A. of 125I labelled prolactin as a function of time depends also on the method used for the labelling and even on every particular labelling process. Therefore we may conclude that, whenever S.A. or parameters derived from its value, such as the mass of the labelled protein, have to be used, the greatest caution must be used in order to avoid misleading results. (M.E.L.)

  15. Increased [125I]trypsin-binding in serum from cystic fibrosis patients

    The capacities of normal and cystic fibrosis (CF) sera to bind to exogenous human [125I]trypsin were compared. Sera from eight older CF patients bound significantly more exogenous human [125I]trypsin than did sera from eight normal subjects (p less than 0.001). Disregarding the increased trypsin-binding (TB) of CF sera, serum immunoreactive trypsinogen (SIRT) levels were not detectable in these eight older CF patients. However, when SIRT levels were corrected for TB, four CF patients had normal SIRT concentrations and four had low but detectable SIRT levels. As compared to five normal newborns' sera, serum from a newborn with CF had normal TB and the SIRT levels were very high. In conclusion, increased TB in CF serum lowers results of SIRT assays. Therefore, unless SIRT levels are corrected for TB, results obtained from currently available SIRT kits may be invalid

  16. Labeling of platelet surface proteins with 125I by the iodogen method

    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

  17. Study on permeability of β-NGF through blood brain barrier by 125I tracing

    β-NGF is extracted from fetus brain by centrifugation, dialysing and ion-exchange chromatography. The molecular weight of β-NGF is 13 kD detected by SDS-PAGE electrophoresis; the isoelectric point of β-NGF are 9.0, 9.2 and 9.3 respectively detected by isoelectric focusing electrophoresis; the β-NGF shows the effect of stimulating neurite growth by PC12 cells culture. Using the 125I tracing technique, the animal experiments indicate (2.41 +- 0.12)% of injected 125I-β-NGF could go through the blood brain barrier at 15 min, and increase to (4.20 +- 0.07)% at 30 min. The results provides scientific basis for research of β-NGF in clinical therapeutic application

  18. Pitfalls of radioisotope diagnosis of deep venous thromboses with 125I-fibrinogen in traumatology

    Experience is described with the examination of deep venous thromboses of the lower extremities using 125I-fibrinogen. Intravenously administered labelled fibrinogen is taken up into the forming thrombus which may then be detected. Experience is presented with preparations of various makes. It was proved that in injured patients the biological half-life of 125I-fibrinogen is reduced to 50 hrs and less as against the standard half-life of 96.2 hrs. This is caused by fibrinogen losses owing to the injury, increased intensity of metabolic processes and the quality of the preparation being used. Injured patients should be examined using a highest quality preparation without denaturation damage to the labelled protein. (Ha)

  19. 7-amino-8-[125I-ketanserin ([125I]AMIK), a highly sensitive, serotonin-S2 receptor ligand

    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)

  20. Cytocidal effect of rifamycin derivatives on ascites tumor cells: studies with (/sup 125/I) iododeoxyuridine

    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.

  1. Effects of hypothyroidism on vascular 125I-albumin permeation and blood flow in rats

    Effects of hypothyroidism on vascular 125I-albumin permeation and on blood flow were assessed in multiple tissues of male Sprague-Dawley rats rendered hypothyroid by dietary supplementation with 0.5% (wt/wt) 2-thiouracil or by thyroidectomy. In both thiouracil-treated and thyroidectomized rats, body weights, kidney weight, arterial blood pressure, and pulse rate were decreased significantly v age-matched controls. After 10 to 12 weeks of thiouracil treatment, 125I-albumin permeation was increased significantly in the kidney, aorta, eye (anterior uvea, choroid, retina), skin, and new granulation tissue, remained unchanged in brain, sciatic nerve, and heart, and was decreased in forelimb skeletal muscle. A similar pattern was observed in thyroidectomized rats, except that increases in 125I-albumin permeation for all tissues were smaller than those observed in thiouracil-treated rats, and 125I-albumin permeation in retina did not differ from controls. In both thiouracil-treated and thyroidectomized rats, changes in blood flow (assessed with 15-microns, 85Sr-labeled microspheres) relative to the decrease in arterial blood pressure were indicative of a decrease in regional vascular resistance except in the choroid and in the kidney, in which vascular resistance was increased significantly. Glomerular filtration rate was decreased, but filtration fraction and urinary excretion of albumin remained unchanged by thiouracil treatment and thyroidectomy. These results indicate that vascular hemodynamics and endothelial cell barrier functional integrity are modulated in many different tissues by the thyroid. In view of the correspondence of hypothyroid- and diabetes-induced vascular permeability changes, these results raise the possibility that altered thyroid function in diabetes may play a role in the pathogenesis of diabetic vascular disease

  2. Differential dose contributions on total dose distribution of 125I brachytherapy source

    Camgz, 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 ...

  3. Specific absorption in vivo of the [125 I] insulin by the Chrysemys dorbigni turtle thyroid

    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

  4. Detection of IgG antibodies against Bordetella pertussis with 125I-protein A

    A method for the detection of IgG antibodies against Bordetella pertussis is described, based on the principle of 'sandwich' radioimmunoassay. 125I protein A is used as radioactive tracer. The influence of amounts of antigen, antibody, radioactive tracer, incubation time and temperature were tested and the optimal conditions for the assay are described. The procedure offers a simple, quick, and sensitive method for detecting antibodies against B. pertussis. Application and limitation of the test are discussed. (orig.)

  5. A one-pot radiosynthesis of [125I]iodoazido photoaffinity labels

    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/μmol) 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)

  6. Localization of 125I-insulin binding sites in the rat hypothalamus by quantitative autoradiography

    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)

  7. Synthesis and biological evaluation of 125I-erythropoietin as a potential radiopharmaceutical agent for tumours

    Gonalo 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 um hormnio glicoprotico responsvel pela regulao da eritropoese. Recentemente foi demonstrado que os receptores de EPO (EPOr esto expressos em algumas linhas celulares neoplsicas, o que sugere a sua potencialidade como um novo alvo teraputico. Neste trabalho a EPO foi radiomarcada com iodo-125 atravs do mtodo da lactoperoxidase, menos agressivo para a viabilidade biolgica das protenas. A 125I-EPO revelou ser radioquimicamente estvel durante 20 dias aps a sntese. Um estudo biolgico in vitro em linhas celulares tumorais demonstrou que a 125I-EPO apresenta uma ligao muito fraca (<2%, tanto em clulas normais como nas linhagens tumorais testadas. A biodistribuio em camundongos saudveis apresentou taxas de fixao relativamente maiores nos rgos excretores e a tireide revelou ser o rgo crtico, o que pode indicar a dissociao in vivo da 125I-EPO. No estudo em camundongos com melanoma induzido a fixao no tumor foi residual. Sero, no entanto, necessrios novos estudos em outras linhagens tumorais para entender o seu processo de internalizao e ligao nas clulas. Estudos da EPO radiomarcada com carbono-11 podero tambm revelar-se interessantes, j que neste mtodo h maior probabilidade da atividade biolgica ser preservada.

  8. A new 125I-anti-DNA-radioimmunoassay for the diagnosis of systematic Lupus erythematosus

    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)

  9. Synthesis and biological evaluation of 125I-erythropoietin as a potential radiopharmaceutical agent for tumours

    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...

  10. 103Pd versus 125I ophthalmic plaque brachytherapy: preoperative comparative radiation dosimetry for 319 uveal melanomas

    Finger, Paul T; Zhou, Di; Kalach, Nina; Semenova, Ekaterina; Choi, Walter

    2014-01-01

    Objective This study was conducted to compare the relative, clinical intraocular dose distribution for palladium-103 (103Pd) versus iodine-125 (125I) ophthalmic plaque radiation therapy. Methods Preoperative comparative radiation dosimetry was performed to evaluate 319 consecutive uveal melanomas treated between 2006 and 2012. Results There were 68 (21.3 %) anterior (iris and/or ciliary body) and 251 (78.7 %) choroidal melanomas examined in this study. According to AJCC staging, 7th edition, ...

  11. Laboratory of radioisotopes of IOCB ASCR - recent results of labeling by 3H and 125I

    Elbert, Tomáš; Veselá, Iva

    2009-01-01

    Roč. 52, 7/8 (2009), s. 253-254. ISSN 0362-4803. [15th Workshop of the International Isotope Society - Central European Division: The synthesis and applications of isotopes and isotopically labelled compounds. 12.06.2009-13.06.2008, Bad Soden] Institutional research plan: CEZ:AV0Z40550506 Keywords : tritium * 125-I labeled peptides Subject RIV: CC - Organic Chemistry

  12. An indirect antibody assay using haptenated antigen and 125I-labelled anti-hapten antibody

    Hapten (trinitrophenyl) was coupled to antigen (ovalbumin). The haptenated antigen was bound by anti-ovalbumin antibody and binding was quantitated with 125I-labelled anti-hapten antibodies. Thus, with a single radioactive reagent, antibodies against a variety of antigens can be detected while the problems inherent in a labelled antiglobulin binding test are avoided. In the ovalbumin system, the haptenated antigen binding test proved to be approximately 20 times as sensitive as the iodinated ovalbumin binding test

  13. 125I-labeled crosslinking reagent that is hydrophilic, photoactivatable, and cleavable through an azo linkage

    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

  14. Effect of body size on accumulation and distribution of 125I in the green mussel (Perna Viridis)

    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.)

  15. 125I-iomazenil - benzodiazepine receptor binding and serum corticosterone level during psychological stress in a rat model

    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

  16. Benzodiazepine effect of 125I-iomazenil-benzodiazepine receptor binding and serum corticosterone level in a rat model

    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

  17. Protein radioiodination in a radioassay laboratory: evaluation of commercial Na125I reagents and related biohazards

    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

  18. Role of mitochondrial DNA in cell death induced by 125I decay

    The role of mitochondrial DNA in radiation-induced cell death was determined by selective [125I]iododeoxyuridine (125IUdR) incorporation into exclusively nuclear sites compared to labelling in both nuclear and mitochondrial DNA of Chinese hamster cells. Such selectivity was achieved by using berenil (25 μg/ml for 24 h), a drug which inhibits mitochondrial DNA synthesis without affecting incorporation of 125IUdR into nuclear DNA but does not result in reduced clonogenicity or cell cycle perturbations or alteration in the X-ray response of cells. There was no difference in cell killing between cells with nuclear labelling alone compared with nuclear plus mitochondrial labelling. The absence of decays in mitochondrial DNA does not affect the ability of 125I to induce lethal cell damage. The two treatment groups have superimposable curves with a D0 of 96 decays/cell. These findings indicate that mitochondrial DNA is not the most sensitive target for radiation-induced cell death from 125I decay. (author)

  19. Portable detectors for 125I-insulin absorption measurement during subcutaneous infusion with portable pumps

    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)

  20. 2[125I]Iodomelatonin binding sites in spleens of guinea pigs

    2-[125I]Iodomelatonin was found to bind specifically to the membrane preparations of the spleens of guinea pigs with high affinity. The binding was rapid, stable, saturable and reversible. Scatchard analysis of the binding assays revealed an equilibrium dissociation constant (Kd) of 49.8±4.12 pmol/l and binding site density (Bmax) of 0.69±0.082 fmol/mg protein at mid-light. There was no significant change in the Kd or the Bmax at mid-dark. Kinetic analysis showed a Kd of 23.13±4.81 pmol/l, in agreement to that derived from the saturation studies. The 2-[125I]iodomelatonin binding sites have the following order of potency: 2-iodomelatonin > melatonin > 6-chloromelatonin much-gt N-acetylserotonin, 6-hydroxymelatonin > 5-methoxytryptamine, 5-methoxytryptophol > serotonin, 5-methoxyindole-3-acetic acid > 5-hydroxytryptophol, 3-acetylindole, 1-acetylindole-3-carboxyaldehyde, L-tryptophan > tryptamine, 5-hydroxyindole-3-acetic acid. Differential centrifugation studies showed that the binding sites are localized mainly in the nuclear fraction, the rest are distributed in the microsomal fraction, mitochondrial fraction and cytosolic fraction. The demonstration of 2-[125I]iodomelatonin binding sites in the spleen suggests the presence of melatonin receptors and a direct mechanism of action of melatonin on the immune system

  1. Correlation of 125I-LSD autoradiographic labeling with serotonin voltage clamp responses in Aplysia neurons

    Evans, M.L.; Kadan, M.J.; Hartig, P.R.; Carpenter, D.O. (New York State Department of Health, State University of New York, Albany (USA))

    1991-05-01

    Autoradiographic receptor binding studies using 125I-LSD (2-(125I)lysergic acid diethyamide) revealed intense labelling on the soma of a symmetrically located pair of cells in the abdominal ganglion of Aplysia californica. This binding was blocked by micromolar concentrations of serotonin and lower concentrations of the serotonergic antagonists, cyproheptadine and mianserin. Electrophysiological investigation of responses to serotonin of neurons in the left upper quadrant, where one of the labeled neurons is located, revealed a range of serotonin responses. Cells L3 and L6 have a K+ conductance increase in response to serotonin that is not blocked by cyproheptadine or mianserin. Cells L2 and L4 have a biphasic response to serotonin: a Na+ conductance increase, which can be blocked by cyproheptadine and mianserin, followed by a voltage dependent Ca2+ conductance which is blocked by Co2+ but not the serotonergic antagonists. Cell L1, and its symmetrical pair, R1, have in addition to the Na+ and Ca2+ responses observed in L2 and L4, a Cl- conductance increase blocked by LSD, cyproheptadine and mianserin. LSD had little effect on the other responses. The authors conclude that the symmetrically located cells L1 and R1 have a Cl- channel linked to a cyproheptadine- and mianserin-sensitive serotonin receptor that is selectively labelled by 125I-LSD. This receptor has many properties in common with the mammalian serotonin 1C receptor.

  2. Pharmacokinetics and tumor retention of 125I-labeled RGD peptide are improved by PEGylation

    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

  3. Influence of 125I seed interstitial brachytherapy on recovery of facial nerve function

    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)

  4. 125I therapy in Graves' disease. Long-term results in 355 patients

    Because of the physical and radiobiologic differences between 125I and 131I, a trial using 125I to treat hyperthyroidism was undertaken in the hope of controlling hyperthyroidism without causing subsequent hypothyroidism. Three hundred fifty-five patients with diffuse toxic goitres were treated and have been under review for an average of 49.4 months: 63.4 percent are euthyroid, 33.5 percent are hypothyroid, and 3.1 percent remain hyperthyroid. Different groups of patients received a wide range of doses of 125I (4.0 to 56.0 mCi), and the lowest incidence of hypothyroidism (23 percent) was in the group that received between 6.0 and 10.5 mCi. Sixty-three percent of the patients whose initial dose was greater than 20.0 mCi are hypothyroid. Persistent hyperthyroidism was common in patients who received small doses. Because of the high incidence of posttreatment hypothyroidism in this series and because 131I has stood the test of time, we believe that 131I is the radionuclide of choice for the routine treatment of hyperthyroidism

  5. A radiolabeled peptide ligand of the hERG channel, [125I]-BeKm-1

    Angelo, Kamilla; Korolkova, Yuliya V; Grunnet, Morten; Grishin, Eugene V; Pluzhnikov, Kirill A; Klaerke, Dan A; Knaus, Hans-Günther; Møller, Morten; Olesen, Søren-Peter

    2003-01-01

    disrupted, resulted in a drop in affinity by more than 300-fold as compared to the wild-type toxin. Iberiotoxin and apamin, peptide inhibitors of Ca2+-activated K+-channels, had no effect on [125I]-BeKm-1 binding. Adding the classical rapid delayed rectifier current (IKr) blocker E-4031 reduced binding of...... had a concentration of half-maximal inhibition (IC50 value) of 27 nM, while wild-type BeKm-1 inhibited hERG channels with an IC50 value of 7 nM. Mono-[125I]-BeKm-1 was found to bind in a concentration-dependent manner and with picomolar affinity to hERG channel protein in purified membrane vesicles...... from transfected human embryonic kidney cells (HEK-293). Under optimized conditions the equilibrium dissociation constant ( Kd) values from saturation and kinetic binding analysis were 13 and 14 pM, respectively. Both the association and dissociation of [(125)I]-BeKm-1 were fast (association rate...

  6. Plasma clearance of human 125I-low density lipoproteins (LDL) in copper-deficient rats

    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

  7. Synthesis and 125I labelling of a precursor for imaging nicotinic acetylcholine receptors

    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)

  8. Characterization of [125I]endothelin-1 binding sites in rat cardiac membrane fragments

    Standard binding and displacement techniques were used to identify high-affinity binding sites for [125I]-labeled endothelin-1 (ET-1) in membranes harvested from the hearts of adult female Sprague-Dawley rats. A single population of binding sites was identified, with a KD of 0.20 +/- 0.03 nM at 37 degrees C, and a Bmax of 93.5 +/- 6.4 fmol/mg protein. Bound [125I]ET-1 was displaced by ET-1 (10(-13)-10(-8) M), with a Ki of 0.08 nM. Neither (-)Bay K 8644 (10(-11)-10(-5) M), prenylamine (10(-11)-10(-5) M), (+)-cis-diltiazem (10(-10)-10(-5) M), (-)D888 (10(-10)-10(-5) M), nicardipine (10(-10)-10(-5) M), lidoflazine (10(-11)-10(-5) M), flunarizine (10(-11)-10(-5) M), omega-conotoxin (10(-13)-10(-7) M), nor prazosin (10(-10)-10(-5) M) displaced the bound ligand. Binding occurred in the absence of Ca2+ and was absent in heat-denatured membranes. These results are interpreted to mean that [125I]ET-1 binds to a single class of high-affinity binding sites that differ from those occupied by known regulators of voltage activated L- and N-type Ca2+ channels

  9. Characterization of (/sup 125/I)endothelin-1 binding sites in rat cardiac membrane fragments

    Gu, X.H.; Casley, D.J.; Nayler, W.G.

    1989-01-01

    Standard binding and displacement techniques were used to identify high-affinity binding sites for (/sup 125/I)-labeled endothelin-1 (ET-1) in membranes harvested from the hearts of adult female Sprague-Dawley rats. A single population of binding sites was identified, with a KD of 0.20 +/- 0.03 nM at 37 degrees C, and a Bmax of 93.5 +/- 6.4 fmol/mg protein. Bound (/sup 125/I)ET-1 was displaced by ET-1 (10(-13)-10(-8) M), with a Ki of 0.08 nM. Neither (-)Bay K 8644 (10(-11)-10(-5) M), prenylamine (10(-11)-10(-5) M), (+)-cis-diltiazem (10(-10)-10(-5) M), (-)D888 (10(-10)-10(-5) M), nicardipine (10(-10)-10(-5) M), lidoflazine (10(-11)-10(-5) M), flunarizine (10(-11)-10(-5) M), omega-conotoxin (10(-13)-10(-7) M), nor prazosin (10(-10)-10(-5) M) displaced the bound ligand. Binding occurred in the absence of Ca2+ and was absent in heat-denatured membranes. These results are interpreted to mean that (/sup 125/I)ET-1 binds to a single class of high-affinity binding sites that differ from those occupied by known regulators of voltage activated L- and N-type Ca2+ channels.

  10. Antibody-recognized [125I]estradiol-receptor complex in ovarian epithelial carcinoma

    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

  11. In vivo binding of /sup 125/I-LSD to serotonin 5-HT/sub 2/ receptors in mouse brain

    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.

  12. In vivo binding of 125I-LSD to serotonin 5-HT2 receptors in mouse brain

    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

  13. Direct linkage of 125I-EGF to cell surface receptors: a useful artifact of chloramine-T treatment

    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

  14. Evaluation of iodogen-coated tubes for 125I-iodination of monoclonal antibodies

    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)

  15. The biological effect of 125I seed continuous low dose rate irradiation in CL187 cells

    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.

  16. 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

    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.)

  17. Development of virtual patient models for permanent implant brachytherapy Monte Carlo dose calculations: interdependence of CT image artifact mitigation and tissue assignment

    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.

  18. 125I-labeled protein A as a general tracer in immunoassay: suitability of goat and sheep antibodies

    The immunoassay method in which 125I-labeled staphylococcal Protein A ([125I]PA) serves as a general tracer has been extended to include goat and sheep IgG antibodies. Goat and sheep IgG normally do not react significantly with PA. However, once IgG antibody is bound to immobilized antigen or hapten, binding of [125I]PA is enhanced markedly. Binding efficiencies of [125I]PA to immune complexed goat anti-human IgM, human IgE, methotrexate and sheep anti-IgE were determined and compared quantitatively to rabbit IgG with the corresponding specificity. Immunoassays were developed based on the inhibition of [125I]PA binding as a measure of antibody inhibition by fluid-phase homologous ligand. Goat antibody to the monovalent hapten methotrexate behaved anomalously: for each concentration of IgG tested, there was an optimal amount of methotrexate beads that gave maximum binding of [125I]PA. In the other immune systems, for each antibody concentration maximum binding of tracer was a function only of the amount of immobilized anitgen added. In contrast to the results obtained with solid-phase antigen, solutions containing antibody and amounts of antigen ranging from large antigen excess to antibody excess failed to react significantly with PA or [125I]PA. (Auth.)

  19. Comparison of 3H-TdR and 125I-UdR incorporation on the proliferation effect of lymphocytes

    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)

  20. 125I-human epidermal growth factor specific binding to placentas and fetal membranes from varoius pregnancy states

    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)

  1. Metabolic and kinetic considerations in the use of [125I]HIPDM for quantitative measurement of regional cerebral blood flow

    The metabolic degradation and the kinetics of the cerebral uptake of N,N,N'-trimethyl-N'-(2-hydroxy-3-methyl-5-[125I]iodobenzyl)-1, 3-propanediamine ([125I]HIPDM) have been studied in conscious, adult male Sprague-Dawley rats to determine its suitability as a tracer for the quantitative measurement of regional CBF (rCBF). rCBF was calculated by the indicator fractionation and the tissue equilibration methods in experiments of different durations up to 1 h. The values of rCBF obtained with [125I]HIPDM were compared with those obtained in concurrent measurements with [14C]iodoantipyrine in the same animals. Results of the experiments demonstrate that [125I]HIPDM is an inadequate tracer for use with the indicator fractionation method and that any method that employs [125I]HIPDM for the determination of rCBF must take into account its metabolic degradation, diffusion limitations, and bidirectional flux across the blood-brain barrier. With the tissue equilibration method, consistent determinations of rCBF may be possible with [125I]HIPDM by measurement of the time course of its concentration in arterial blood, corrected for the presence of 125I-labeled metabolic products, and its concentration in the brain at any time up to 1 h after its administration. The method may be adapted to measure rCBF in humans by means of single-photon emission tomography with [123I]HIPDM

  2. Retrograde axonal transport of 125I-nerve growth factor in rat ileal mesenteric nerves. Effect of streptozocin diabetes

    The retrograde axonal transport of intravenously (i.v.) administered 125I-nerve growth factor (125I-NGF) was examined in mesenteric nerves innervating the small bowel of rats with streptozocin (STZ) diabetes using methods described in detail in the companion article. The accumulation of 125I-NGF distal to a ligature on the ileal mesenteric nerves of diabetic animals was 30-40% less than in control animals. The inhibition of accumulation of 125I-NGF in diabetic animals was greater at a ligature tied 2 h after i.v. administration than at a ligature tied after 14 h, which suggests that the diabetic animals may have a lag in initiation of NGF transport in the terminal axon or retardation of transport at some site along the axon. The 125I-NGF transport defect was observed as early as 3 days after the induction of diabetes, a time before the development of structural axonal lesions, and did not worsen at later times when dystrophic axonopathy is present. Both the ileal mesenteric nerves, which eventually develop dystrophic axonopathy in experimental diabetes, and the jejunal mesenteric nerves, which never develop comparable structural alterations, showed similar 125I-NGF transport deficits, suggesting that the existence of the transport abnormality does not predict the eventual development of dystrophic axonal lesions. Autoradiographic localization of 125I-NGF in the ileal mesenteric nerves of animals that had been diabetic for 11-13 mo demonstrated decreased amounts of 125I-NGF in transit in unligated paravascular nerve fascicles. There was, however, no evidence for focal retardation of transported 125I-NGF at the sites of dystrophic axonal lesions

  3. Specific uptake, dissociation, and degradation of 125I-labeled insulin in isolated turtle (Chrysemys dorbigni) thyroid glands

    Thyroid glands from turtles (Chrysemys dorbigni) pretreated with potassium iodide were incubated with 125I-insulin in the presence or absence of unlabeled insulin, in order to study its specific uptake. At 24 degrees, the specific uptake reached a plateau at 180 min of incubation. The dose of bovine insulin that inhibited 50% of the 125I-insulin uptake was 2 micrograms/ml of incubation medium. Most of the radioactive material (71%) extracted from the gland, after 30 min incubation with 125I-insulin, eluted in the same position as labeled insulin on Sephadex G-50. Only 24% eluted in the salt position. After 240 min incubation, increased amount of radioactivity appeared in the Na125I position. When bovine insulin was added together with the labeled hormone, a substantial reduction of radioactivity was observed in the insulin and Na125I elution positions. Dissociation studies were performed at 6 degrees in glands preincubated with 125I-insulin either at 24 or 6 degrees. The percentage of trichloroacetic acid (TCA)-soluble radioactive material in the dissociation medium increased with incubation time at both temperatures. However, the degradation activity was lower at 6 than at 24 degrees. The addition of bovine insulin to the incubation buffer containing 125I-insulin reduced the radioactive degradation products in the dissociated medium. Chloroquine or bacitracin inhibited the degradation activity. Incubation of thyroid glands with 125I-hGH or 125I-BSA showed values of uptake, dissociation, and degradation similar to those experiments in which an excess of bovine insulin was added together with the labeled hormone. Thus, by multiple criteria, such as specific uptake, dissociation, and degradation, the presence of insulin-binding sites in the turtle thyroid gland may be suggested

  4. DNA strand breakage by 125I-decay in a synthetic oligodeoxynucleotide. Quantitative analysis of fragment distribution

    The DNA breakage produced by decay of 125I in a double-stranded 41 bp oligodeoxynucleotide was investigated by DNA sequencing gel analysis. Use of both 5'- and 3'-end 32P labelling of the 125I containing strand provided the single-stranded breakage pattern at either side of the 125I-dC. The asymmetric pattern of breakage relative to the 125I-labelled nucleotide enabled deconvolution of two components of breakage. One of them declines very quickly with nucleotide number from 125I-dC and dominates within 4-5 nucleotides. We assume this component to be associated with neutralisation of charged Te atom resulted from decay, or/and with radiation damage to an initial target other than the deoxyribosyl moiety - probably the bases. The second component depends on the geometrical distance between the 125I atom and deoxyribosyl atoms. These two components are responsible for breakage under conditions limiting radical mediated damage, namely in the presence of 2 M dimethylsulphoxide. The third component, associated with radical-mediated damage, contributes to the total breakage during incubation in 20 mM phosphate buffer alone, and under these incubation conditions dominates the breakage beyond 8-9 nucleotides from 125I-dC. The estimated average numbers of single-stranded breaks produced in the 125I-containing strand by each mechanism in 41-mer oligodeoxynucleotide with 125I-dC at 21st position are respectively 2.33, 0.98 and 0.63. (orig.)

  5. A Dose–Response Analysis of Biochemical Control Outcomes After 125I Monotherapy for Patients With Favorable-Risk Prostate Cancer

    Purpose: To define the optimal dose for 125I prostate implants by correlating postimplantation dosimetry findings with biochemical failure and toxicity. Methods and Materials: Between 2003 and 2009, 683 patients with prostate cancer were treated with 125I prostate brachytherapy without supplemental external beam radiation therapy and were followed up for a median time of 80 months. Implant dose was defined as the D90 (the minimal dose received by 90% of the prostate) on postoperative day 1 and 1 month after implantation. Therefore, 2 dosimetric variables (day 1 D90 and day 30 D90) were analyzed for each patient. We investigated the dose effects on biochemical control and toxicity. Results: The 7-year biochemical failure-free survival (BFFS) rate for the group overall was 96.4% according to the Phoenix definition. A multivariate analysis found day 1 D90 and day 30 D90 to be the most significant factors affecting BFFS. The cutoff points for day 1 D90 and day 30 D90, calculated from ROC curves, were 163 Gy and 175 Gy, respectively. By use of univariate analysis, various dosimetric cutoff points for day 30 D90 were tested. We found that day 30 D90 cutoff points from 130 to 180 Gy appeared to be good for the entire cohort. Greater D90s were associated with an increase in late genitourinary or gastrointestinal toxicity ≥ grade 2, but the increase was not statistically significant. Conclusions: Improvements in BFFS rates were seen with increasing D90 levels. Day 30 D90 doses of 130 to 180 Gy were found to serve as cutoff levels. For low-risk and low-tier intermediate-risk prostate cancer patients, high prostate D90s, even with doses exceeding 180 Gy, achieve better treatment results and are feasible

  6. A Dose–Response Analysis of Biochemical Control Outcomes After {sup 125}I Monotherapy for Patients With Favorable-Risk Prostate Cancer

    Shiraishi, Yutaka, E-mail: shiraishi@rad.med.keio.ac.jp [Department of Radiology, Keio University School of Medicine, Tokyo (Japan); Department of Radiology, National Hospital Organization Tokyo Medical Center, Tokyo (Japan); Yorozu, Atsunori [Department of Radiology, National Hospital Organization Tokyo Medical Center, Tokyo (Japan); Ohashi, Toshio [Department of Radiology, Keio University School of Medicine, Tokyo (Japan); Toya, Kazuhito [Department of Radiology, National Hospital Organization Tokyo Medical Center, Tokyo (Japan); Saito, Shiro; Nishiyama, Toru; Yagi, Yasuto [Department of Urology, National Hospital Organization Tokyo Medical Center, Tokyo (Japan); Shigematsu, Naoyuki [Department of Radiology, Keio University School of Medicine, Tokyo (Japan)

    2014-12-01

    Purpose: To define the optimal dose for {sup 125}I prostate implants by correlating postimplantation dosimetry findings with biochemical failure and toxicity. Methods and Materials: Between 2003 and 2009, 683 patients with prostate cancer were treated with {sup 125}I prostate brachytherapy without supplemental external beam radiation therapy and were followed up for a median time of 80 months. Implant dose was defined as the D90 (the minimal dose received by 90% of the prostate) on postoperative day 1 and 1 month after implantation. Therefore, 2 dosimetric variables (day 1 D90 and day 30 D90) were analyzed for each patient. We investigated the dose effects on biochemical control and toxicity. Results: The 7-year biochemical failure-free survival (BFFS) rate for the group overall was 96.4% according to the Phoenix definition. A multivariate analysis found day 1 D90 and day 30 D90 to be the most significant factors affecting BFFS. The cutoff points for day 1 D90 and day 30 D90, calculated from ROC curves, were 163 Gy and 175 Gy, respectively. By use of univariate analysis, various dosimetric cutoff points for day 30 D90 were tested. We found that day 30 D90 cutoff points from 130 to 180 Gy appeared to be good for the entire cohort. Greater D90s were associated with an increase in late genitourinary or gastrointestinal toxicity ≥ grade 2, but the increase was not statistically significant. Conclusions: Improvements in BFFS rates were seen with increasing D90 levels. Day 30 D90 doses of 130 to 180 Gy were found to serve as cutoff levels. For low-risk and low-tier intermediate-risk prostate cancer patients, high prostate D90s, even with doses exceeding 180 Gy, achieve better treatment results and are feasible.

  7. Role of hormonal therapy in the management of intermediate- to high-risk prostate cancer treated with permanent radioactive seed implantation

    Purpose: To study the impact of hormonal therapy (HTx) on intermediate- to high-risk prostate cancer treated with permanent radioactive seed implantation. Methods and Materials: Patients with Stage T1b-T3bN0 prostate cancer, and Gleason score ≥7 or prostate-specific antigen (PSA) level >10 ng/mL were treated with seed implantation with or without HTx. Their disease was defined as intermediate risk (PSA 10-20, Gleason score 7, or Stage T2b) or high risk (two or more intermediate criteria, or PSA >20 ng/mL, Gleason score 8-10, or Stage T2c-T3). The median follow-up for 201 eligible patients was 42 months (range 18-110). Biochemical failure was defined as a rising PSA >1.0 ng/mL. Pretreatment disease characteristics, implant dose, and HTx were evaluated using univariate and multivariate analyses. Results: HTx significantly improved 5-year actuarial freedom from biochemical failure rate, 79% vs. 54% without HTx. In addition, high-dose, PSA ≤15 ng/mL, intermediate risk, and Stage T2a or lower significantly improved outcome in the univariate analyses. HTx was the most significant predictor of 5-year actuarial freedom from biochemical failure (p <0.0001) in a multivariate analysis. The best outcome was in the intermediate-risk patients treated with a high implant dose and HTx, resulting in a 4-year actuarial freedom from biochemical failure rate of 94%. Conclusion: In this retrospective review, HTx improved outcome in intermediate- to high-risk prostate cancer patients treated with brachytherapy. HTx was the most important prognostic factor in the univariate and multivariate analyses

  8. Molecular suicide studies of 125I and 3H disintegration in the DNA of Chinese hamster cells

    Several recent experiments are discussed which yield some new data to help further understand the dramatic sensitivity of mammalian cells to 125I induced reproductive death. The authors discuss the effects of halogenated pyrimidines on removing the shoulder of the survival curve after tritium thymidine suicide; the effect of oxygen on 125I decay effects as a functions of the localization of the decays within the nucleus; and recent data on the induction of chromosome aberrations by 125I DNA decays in CHO cells stored in the G1-stage of the cell cycle. (B.R.H.)

  9. A rapid means of separating A14-125I-insulin from heterogeneously labeled insulin molecules for biologic studies

    We have used two methods for the preparation of a highly homogeneous insulin with high specific activity. After iodination with chloramine T, the labeled peptides were retained on a disposable Sep Pak cartridge and subsequently eluted. The eluted labeled insulins were further purified by either DEAE cellulose or high performance liquid chromatography (HPLC) to separate A14-125I- from A19-125I-insulin. Both methods of chromatography were effective, but HPLC offered the advantage of better resolution in less time and higher yields of A14-125I-insulin, which is suitable for biologic studies in various target tissues

  10. First permanent human implant of the Stimulus Router System, a novel neuroprosthesis: preliminary testing of a polarity reversing stimulation technique.

    Gan, Liu Shi; Ravid, Einat N; Kowalczewski, Jan; Gauthier, Michel; Olson, Jaret; Morhart, Michael; Prochazka, Arthur

    2011-01-01

    Neuroprostheses (NPs) are electrical stimulators that help to restore sensory or motor functions lost as a result of neural damage. The Stimulus Router System (SRS) is a new type of NP developed in our laboratory. The system uses fully implanted, passive leads to "capture" and "route" some of the current flowing between pairs of surface electrodes to the vicinity of the target nerves, hence eliminating the need for an implanted stimulator. In June 2008, 3 SRS leads were implanted in a tetraplegic man for restoration of grasp and release. To reduce the size of the external wristlet and thereby optimize usability, we recently implemented a polarity reversing stimulation technique that allowed us to eliminate a reference electrode. Selective activation of three target muscles was achieved by switching the polarities of the stimulus current delivered between pairs of surface electrodes located over the pick-up terminals of the implanted leads and reducing the amplitude of the secondary phases of the stimulus pulses. PMID:22254983

  11. A study of thyroid contaminations with 125I and of their blocking

    A sensitive method for the detection of 125I contaminations of the thyroid was set up, the uptakes being determined by comparison with a standard curve, obtained by placing various calibrated sources of in a neck phantom. The detector efficiency was of the order of 0.25% with a stability of +- 0.011% (CV=4.4%) over a six month period. Accuracy was also confirmed, while precision studies showed an inter measurement coefficient of variation of 2 - 6 % when the measured activities were above 1 kBq. Sensitivity determined according to two different definitions ranged between 30 and 80 Bq. Thirty workers, performing routine 125I labeling in several laboratories of the city of Sao Paulo (Brazil), were monitored, 25 of which (83%) presented significant thyroid contaminations, the maximum being 24 kBq (650 nCi) at the moment of first detection. In five individuals the effective half-life of life of 125I could also be calculated, with enough precision, resulting in a value of 39.4 +- 6.1 d. With basis on these findings and methodology a study was carried out in an animal model (dog) in order to find an useful correlation between maximum thyroid uptake and radioiodine urinalysis at a certain time after contamination, that still could allow the intervention with an adequate blocking agent. The best correlation was found considering 125I thyroid uptake 48 hours (T-48) and urine radioactivity 4 to 6 hours (U-4, U-5, U-6) after contamination (r = 0.974 with a level of significance pT-48 = 0.790 XU-4 + 2.973. could also be calculated, with enough precision, resulting in a value of 39.4 +- 6.1 d. With basis on these findings and methodology a study was carried out in an animal model (dog) in order to find an useful correlation between maximum thyroid uptake and radioiodine urinalysis at a certain time after contamination, that still could allow the intervention with an adequate blocking agent. The best correlation was found considering 125I thyroid uptake 48 hours (T-48) and urine radioactivity 4 to 6 hours (U-4, U-5, U-6) after contamination (r = 0.974 with a level of significance pT-48 = 0.790 XU-4 + 2.973. An analogous study, carried out in humans to which was administered, presented a similar correlation and level of significance : YT-24 = 1.162 XU-4 + 3.263 (r = 0.9265; p125I or 131I, showing a good agreement between measured and extrapolated thyroid uptake, with a mean difference of less than 10%. Three different blocking agents were tested : potassium iodide and perchlorate and tapazol. The first two compounds presented a blocking action of about 90% while the third of 24% only. Potassium iodide was chosen due to its limited side effects and a final study, carried out with different doses, indicated that 25 mg of KI should be the ideal amount to be administered to the dog. This corresponds to an extrapolated amount of approximately 100 mg for a 70 kg human, the same being recommended by various authors. (author)

  12. Stability of 125I and 14C labelled boom clay organic matter

    The candidate host formation for the disposal of radioactive waste in Belgium is boom clay which may contain up to 4% organic matter (OM). A limited fraction (less than 0.05%) of this OM is mobile. OM can complex radionuclides and so influence their migration. The migration behaviour of the OM itself has been extensively studied but to date such studies have used absorbancy measurements to quantify the OM. Unfortunately various problems accompany the use of absorbancy measurements. The particular problems may be overcome by using radiolabelled OM. Accordingly as a precursor to planned in situ migration experiments in boom clay (BC) using radiolabelled OM, stability studies on 125I and 14C labelled materials have been conducted. The 125I containing solutions were analysed using gel permeation chromatography (GPC) and the 14C solutions using high performance size exclusion chromatography (HPSEC). Dissappointingly at the relevant pH of 8.5, even in the absence of the clay, the 125I label was found to be unstable. However the 14C labelled OM (14C-BC-OM) was stable under the mild conditions employed in the test, so its stability was investigated in the presence of boom clay. The results were compared with that of 14C labelled humic acids (14C-HA), treated similarly. Unexpectedly the 14C labelled material was found to be partially unstable in the presence of boom clay. However the instability has not hampered the laboratory column experiments and should not hamper the proposed in situ experiments with this material. (orig.)

  13. Autoradiographic study on the distribution of 125I-inhibin in rat pituitary and hypothalamus

    Objective: It is not yet clear about the location and exact mechanism of inhibin (INH) acting in brain. Our previous study in vitro reported that INH could cross blood-brain barrier (BBB). The aim of the current study was to investigate whether INH was able to cross BBB in vivo and its distribution in pituitary or hypothalamus. Methods: Twenty SD rats were divided into 4 groups with 50 μl of 125I-INH injected through jugular vein in groups 1, 2 and 3 and with the same volume of saline in group 4 (control). The rats of group 1,2 and 3 were sacrificed at 30, 60 and 120 min after 125I-INH administration. The radioactivity of the pituitaries and hypothalami were immediately counted. The pituitaries and hypothalami of the highest radioactivity and of control group were selected for autoradiographic analysis. Results: The highest radioactivity of pituitary was found in group 1[(1008.00±5.78)Bq], higher than groups 2 and 3 [(723.00±4.95) and (491.00±4.90) Bq, respectively]. It was suggested that the radioactivity of pituitary declined with time. The radioactivity of hypothalami in the three groups were (20.00±1.01), (22.00±0.95) and (19.00±0.73) Bq, respectively. The radioactivity of the pituitary and hypothalami in controls were (16.00±1.40) and (15.00±0.98) Bq, respectively. A significant difference existed in the pituitary radioactivity between the experimental (groups 1, 2 and 3) and control (P125I-INH may pass through BBB in rat. The binding site or receptor for INH might exist in the pituitary rather than in hypothalamus. (authors)

  14. Labelling and validation of progesterone-11-α-hydroxy hemisuccinate (125I)

    Progesteron is a steroid hormone secreted by the corpus luteum and the adrenal cortex in the hypophise gland. The hormone can be used for monitoring pregnancy and even more for the assessment of the corpus luteum in fertile woman (4). The labelling of progesterone with 125I was carried out for tracer production in the preparation of Progesterone Kit used in the determination of the progesterone derivate has been done. The labelling was carried out in two steps reaction. First the progesterone derivate was activated using N-methyl morpholine and isobutylchloroformate. The second step was performed by conjugating the labelled 125I Histamin to the activated progesterone derivate. The labelled compound was purified with HPLC followed with the determination of the chemical purity using electrophorosis, the immunoreactivity controlled with the maximum binding of the zerro standard and the non specific binding using the Progesterone Kit. Experimental results showed that the iodination of Progesterone -11-α-hidroxy hemisuccinate (125I) yield 22.15%, chemical purity 92.30%, the radioimmunoreactivity 51% as maximum binding (for zero standard), with NSB 0.67%, and the spesific activity obtained 7.72 Ci/ g. Validation of the tracer using control (low, medium and high) shows the results as follows : (2.72 ± 0.49)nmol/L for low standard and control (1.2 - 2.5 nmol/L), (11.3 ± 1.15) nmol/L for medium standard and control (6-15 n/mol) and (15.95 5.32 ) nmol/L for high standard and control (10-23 nmol/L). The sensitivity of the assay was (0.70 ± 0.024 nmol/L) for zero standard

  15. An improved synthesis of an 125I and 211At labelled benzamide for melanoma imaging

    Recent studies have indicated that benzamides can exhibit affinity for malignant melanoma and may be exploited diagnostically in the treatment of this cancer. Radioiodinated N-(2-diethylaminoethyl)-3-[123I/131I]iodo-4-methoxybenzamide (*I-IMBA) is a benzamide with promising diagnostic properties. A new synthesis procedure was developed to obtain 125I-IMBA suitable for use in vivo. The assets of the procedure include the use of less toxic reagents and better reproducible results when radiolabelling the precursor. The procedure also facilitates the synthesis of the astatinated N-(2-diethylaminoethyl)-3-[211At]astatine-4-methoxybenzamide (211At-AMBA), a new benzamide with a therapeutic potential. The regiospecific no-carrier-added 125I- and 211At-labeling of the benzamide is performed by demetalation of an organotin precursor. Using tributylstannyl as a leaving group, the radiochemical yield obtained after 15 minutes of reaction was 70 %-90 % for both 125I-IMBA and 211At-AMBA. The labelling was performed in a solution of MeOH:AcOH with NCS as the oxidising agent. The organotin precursor N-(2-diethylaminoethyl)-3-(tri-n-butylstannyl)-4-methoxy-benzamide was synthesized from 3-bromo-4-methoxybenzoic acid, with n-BuLi (2 eq) and Bu3SnCl (1 eq) in THF, giving 3-(tri-n-butylstannyl)-4-methoxybenzoic acid. The amide function was introduced by converting the acid group into an active N-succinimidyl-ester, a good leaving group in the reaction with 2-(diethylamino)ethylamine. The overall yield of the organotin precursor was 65 %

  16. Novel high resolution 125I brachytherapy source dosimetry using Ge-doped optical fibres

    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

  17. Preclinical pharmacological study on 125I-ADAM as a serotonin transporter ligand

    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)

  18. Correlation between the estimated molecular weight and the immunological properties of 125I-TSH

    Thyrotropic Stimulating Hormone (TSH) was radioiodinated by the Chloramine T method in order to be used in radioimmu-noassay procedures. It was purified by gel filtration and each fraction of the eluate was analyzed in order to determine which one had the most suitable behaviour for that use. The molecular weight of each fraction was estimated, as well as its immunological reactivity and its non-specific binding. The 125I-TSH fraction with better properties was the closest to the molecular weight of the native hormone, which is found at the posterior shoulder of the main proteic peak of the elution pattern. (author)

  19. Ocular penetration of (125I)IVDU, a radiolabeled analogue of bromovinyldeoxyuridine

    Following topical application of (125)IVDU, the radiolabeled analogue of bromovinyldeoxyuridine ([E]-5-[2-bromovinyl]-2'-deoxyuridine), as 0.5% or 0.3% eyedrops, to rabbits, (125I)IVDU appeared in the anterior chamber fluid at drug levels well above the minimum concentration (0.01 microgram/mL) required for inhibition of herpes simplex virus type 1 replication. These findings are consistent with the efficacy of 0.5% bromovinyldeoxyuridine eyedrops in the topical treatment of herpes simplex uveitis

  20. Labelling of human follicle stimulant hormone with 125I, for radioimmunoassay

    An efficient labeling of human Follicle Stimulant Harmone is essential to development of sensitive radioimmunoassays. Iodination by Chloramine T method frequently is subject to severe iodination damage and some preparations are unaccetable for radioimmunoassays. Modifications to the Hunter method, changing incubation time, reaction temperature and reducing Chloramine T amount used in the reaction, were performed in obtaining a more effective labeling. FSH-125 I fraction obtained from Sephadex G-75 column purification presented excellent immunoreactivity and quality control of the steps of the reaction demonstrated a high percentage (90%) of intact Follicle Stimulant Hormone

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

    In this first report it is described the synthesis, separation and purification of the 2-radioiodinated histamine- I-labelled histamine by a mixed anhydride reaction. About 75% incorporation of I-125, from Na125I, 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 μCi/μg. Dissolved in ethanol and held at -20 degree centigree under darkness decomposition on storage didn't exceed 1% per month. (Author) 13 refs

  2. A method for the determination of 125I in air by collecting on a polyurethane foam

    A resilient polyurethane foam cylinder was used for collecting airborne radioiodine in the exhaust of a plant producing 125I-labelled compounds. The cylinder was used unimpregnated or impregnated with technical long-chain tri-n-alkylamine type Alamine 336 with or without dissolved inactive elemental iodine. After compressing the foam cylinder into the smallest possible volume, the activity of the collected radioiodine was measured using a conventional well-type NaI(Tl) detector with a very favourable counting efficiency. (author). 1 fig., 1 tab., 11 refs

  3. 125I-labeling and purification of peptide hormones and bovine serum albumin

    The iodination and separation of various diagnostically and/or experimentally important peptides including (Tyr1)-somatostatin-14, rat Tyr-α-calcitonin gene-related peptide (23-37), motilin and vasoactive intestinal peptide, furthermore bovine serum albumin are described. All species were iodinated by the iodogen method. The 125I-labeled peptide products were separated by reversed-phase HPLC, the specific activities of mono-iodinated forms are near identical with the theoretical value. The labeled bovine serum albumin was separated by Sephadex G-100 gel filtration. (author)

  4. Synthesis and biological activity of 125I/127I-phenylboronic acid derivatives

    Three iodinated phenylboronic acids have been synthesized: 4-iodophenylboronic acid (2a), 3-(4-iodobenzenesulfonamido) phenylboronic acid (5a) and 3-(5-dimethylamino-6-iodo-1-naphthalene-sulfonamido)-phenylboronic acid (6a). The corresponding no-carrier-added 125I derivatives 2b, 5b and 6b have been prepared in good yield by selective displacement of the tributylstannyl group. Compound 6b was concentrated in vitro preferentially in HT-29 human colon carcinoma cells compared to V79 Chinese hamster lung fibroblasts and showed selective retention in PaCa-2 human pancreatic cancer cells grown as solid tumor xenografts in the nude mouse. (author)

  5. Preparation Of Labeled Prolactin By 125I Using Lactoperoxidase And Iodogen

    The present study was carried out to prepare 125I-prolactin (PRL) tracer, using different oxidizing agents such as iodogen and lactoperoxidase, which was purified by column sephadex G-100 and used to measure the prolactin in human serum by radioimmunoassay (RIA) technique. The conditions of radioiodination such as concentration of oxidizing agent, reaction time, concentration of prolactin and effect of ph were studied to get maximum yield. Stability study of prolactin tracers was carried out. The prolactin standards were prepared using highly purified PRL antigen with phosphate buffer (ph 7.4, 0.05 M). Optimization of the assay was carried out.

  6. Penicillin-binding proteins of Escherichia coli identified with a 125I-derivative of ampicillin

    Evaluation of the binding of ?-lactam antibiotics to penicillin-binding proteins (PBPs) in the bacterial cell wall by the established method using 14C-labelled penicillin G has some disadvantages. Due to the small number of PBP molecules and the relatively low specific activity of [14C]penicillin G available, very long exposure times for autoradiography are required. Furthermore, additional radiolabelled derivatives of penicillin with modified binding patterns might reveal PBPs not known so far. The authors describe the synthesis of a 125I-labelled derivative of ampicillin and the labelling of PBPs with this compound. (Auth.)

  7. 125I-?-sec-butyl-p-hydroxybenzyl alcohol receptor competitive binding assays in animal body

    Based on the receptor competitive binding assays in the mice and rat body, it has been proved that both diazepam and ?-sec-butyl-p-hydroxybenzyl alcohol (G-018) can inhibit 125I-G-018 binding with brain benzodiazepine receptor. Inhibiting effects were obvious in the cortex, cerebellum, hippocampus and midbrain. But in the medulla blongata and hypothalamus no inhibiting effect was observed. Experimental results have demonstrated that the inhibiting effect is consistent with distribution of benzodiazepine receptor in the brain. Also, experimental results have shown no difference between in vitro and in vivo. The G-018 binding with benzodiazepine receptor has been clarified under physiologic conditions

  8. Portable multiwire proportional chamber imaging system for high resolution 125I imaging

    A dedicated multiwire proportional chamber system designed to image 125I labeled venous thrombi is described. The chamber is filled with a Kr-Co2 gas mixture at one atmosphere pressure and utilizes an externally mounted delay line readout. A pair of crossed x-ray grids form a collimator which yields an optimum system efficiency of 3.1 x 10-4 for a fixed spatial resolution of 0.74 cm. The chamber is further designed to be lightweight and portable for in-hospital use

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

    Dyrberg, T; Billestrup, Nils

    1984-01-01

    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...... 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...

  10. Ocular penetration of (/sup 125/I)IVDU, a radiolabeled analogue of bromovinyldeoxyuridine

    Maudgal, P.C.; Verbruggen, A.M.; De Clercq, E.; Busson, R.; Bernaerts, R.; de Roo, M.; Ameye, C.; Missotten, L.

    1985-01-01

    Following topical application of (/sup 125/)IVDU, the radiolabeled analogue of bromovinyldeoxyuridine ((E)-5-(2-bromovinyl)-2'-deoxyuridine), as 0.5% or 0.3% eyedrops, to rabbits, (/sup 125/I)IVDU appeared in the anterior chamber fluid at drug levels well above the minimum concentration (0.01 microgram/mL) required for inhibition of herpes simplex virus type 1 replication. These findings are consistent with the efficacy of 0.5% bromovinyldeoxyuridine eyedrops in the topical treatment of herpes simplex uveitis.

  11. Quantitative autoradiography of [125I] apamin binding sites in the central nervous system.

    Janicki, P K; Horvath, E; Seibold, G; Habermann, E

    1984-01-01

    The binding sites for [125I] apamin in the central nervous system of rat, guinea-pig, chicken and frog were assessed by quantitative autoradiography on X-ray film. In rat and guinea-pig brain apamin labels preferentially the limbic-olfactory system, i.e. nucleus olfactorius, nuclei septi, habenula and hippocampus. In the rat spinal cord the peptide binds preferentially to the substantia gelatinosa. Tectum opticum and nuclei isthmi are labelled in chicken brain. In frog brain no preferentially "apamin-stained" area was found. The role of the cerebral binding sites is still unknown, whereas the spinal sites may be involved in apamin poisoning. PMID:6335967

  12. Quantitative autoradiography of [125I] apamin binding sites in the central nervous system

    The binding sites for [125I] apamin in the central nervous system of rat, guinea-pig, chicken and frog were assessed by quantitative autoradiography on X-ray film. In rat and guinea-pig brain apamin labels preferentially the limbic-olfactory system, i.e. nucleus olfactorius, nuclei septi, habenula and hippocampus. In the rat spinal cord the peptide binds preferentially to the substantia gelatinosa. Tectum opticum and nuclei isthmi are labelled in chicken brain. In frog brain no preferentially 'apamin-stained' area was found. The role of the cerebral binding sites is still unknown, whereas the spinal sites may be involved in apamin poisoning. (author)

  13. Quantitative autoradiography of (/sup 125/I) apamin binding sites in the central nervous system

    Janicki, P.K.; Horvath, E.; Habermann, E. (Giessen Univ. (Germany, F.R.). Rudolf-Buchheim-Institut fuer Pharmakologie); Seibold, G. (Giessen Univ. (Germany, F.R.). Strahlenzentrum)

    1984-12-01

    The binding sites for (/sup 125/I) apamin in the central nervous system of rat, guinea-pig, chicken and frog were assessed by quantitative autoradiography on X-ray film. In rat and guinea-pig brain apamin labels preferentially the limbic-olfactory system, i.e. nucleus olfactorius, nuclei septi, habenula and hippocampus. In the rat spinal cord the peptide binds preferentially to the substantia gelatinosa. Tectum opticum and nuclei isthmi are labelled in chicken brain. In frog brain no preferentially 'apamin-stained' area was found. The role of the cerebral binding sites is still unknown, whereas the spinal sites may be involved in apamin poisoning.

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

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

  15. ( sup 125 I)-2-(2,5-dimethoxy-4-iodophenyl)aminoethane (( sup 125 I)-2C-I) as a label for the 5-HT2 receptor in rat frontal cortex

    Johnson, M.P.; Mathis, C.A.; Shulgin, A.T.; Hoffman, A.J.; Nichols, D.E. (Purdue Univ., West Lafayette, IN (USA))

    1990-01-01

    Recent studies of 5-HT2 receptor binding have involved the use of radiolabeled agonists. This report describes the use of ({sup 125}I)-2-(2,5-dimethoxy-4-iodophenyl)aminoethane (({sup 125}I)-2C-I) as a label for low-density 5-HT2 agonist binding sites. A nonhydrolyzable analog of GTP, GppNHp, was found to inhibit the high affinity binding of ({sup 125}I)-2C-I. 5-HT and several 5-HT2 agonists and antagonists displayed high affinity for this site. In addition, a significant decrease in the Bmax value, but not the KD for ({sup 125}I)-2C-I was observed at 37 degrees C as compared to that observed at 24 degrees C. Several structure-activity relationships were investigated for displacement of ({sup 125}I)-2C-I, and the results are consistent with the importance of this receptor in the mechanism of action of hallucinogens. This study demonstrates the utility of ({sup 125}I)-2C-I as a novel radioligand and provides further data that the 5-HT2 receptor is significantly linked to hallucinogenic activity for several compounds.

  16. [125I]-2-(2,5-dimethoxy-4-iodophenyl)aminoethane ([125I]-2C-I) as a label for the 5-HT2 receptor in rat frontal cortex

    Recent studies of 5-HT2 receptor binding have involved the use of radiolabeled agonists. This report describes the use of [125I]-2-(2,5-dimethoxy-4-iodophenyl)aminoethane ([125I]-2C-I) as a label for low-density 5-HT2 agonist binding sites. A nonhydrolyzable analog of GTP, GppNHp, was found to inhibit the high affinity binding of [125I]-2C-I. 5-HT and several 5-HT2 agonists and antagonists displayed high affinity for this site. In addition, a significant decrease in the Bmax value, but not the KD for [125I]-2C-I was observed at 37 degrees C as compared to that observed at 24 degrees C. Several structure-activity relationships were investigated for displacement of [125I]-2C-I, and the results are consistent with the importance of this receptor in the mechanism of action of hallucinogens. This study demonstrates the utility of [125I]-2C-I as a novel radioligand and provides further data that the 5-HT2 receptor is significantly linked to hallucinogenic activity for several compounds

  17. The recommendations of the international commission on radiological protection (ICRP) for high-dose-rate brachytherapy and for permanent prostatic implants

    ICRP (International Commission for Radiological Protection) Committee 3 ('Radioprotection in medicine') is currently finalizing two recommendations about Brachytherapy. The first text, from Task Group (TG) 53, is focussing on the prevention of high-dose-rate brachytherapy accidents. It reminds the reader of the 500 accidents/incidents which have been reported so far in the literature, and reports in details on some representative accidents. Building on those data, the text gives general and specific recommendations, aiming at reducing both the frequency and the severity of those accidents. The second text, from Task Group 57, considers the radiation safety aspects of brachytherapy for prostate cancer using permanently implanted sources. For this topic, no severe accident has never been reported so far. However, some radioprotection problems arose, due to the dose received from the patients, to migrating seeds and to cremation. The text presents recommendations specifically addressing those issues. (authors)

  18. Successful implantation of a permanent pacemaker through a persistent left superior vena cava by using a right subclavian approach

    Jovi? Zoran

    2011-01-01

    Full Text Available Introduction. Persistent left superior vena cava, a rare congenital abnormality, can complicate placement of pacemaker leads through the subclavian vein. A left-sided approach is usually preferable in such cases. Case report. We reported a case in which we began a single-chamber pacemaker implantation procedure via a right subclavian approach (because of scarring beneath the left clavicle and then discovered intraoperatively that the patient had a persistent left superior vena cava. After a few attempts, we succeeded in placing the head of the electrode in the septum, near the top of the right ventricle, and the rest of the procedure was completed without complication. Conclusion. To our knowledge, this is the first reported case of pacemaker implantation, with passive electrode, through a persistent left superior vena cava via the right subclavian vein. This case demonstrates that such an approach, when necessary, can be used successfully.

  19. Comparison of (/sup 125/I)iodolysergic acid diethylamide binding in human frontal cortex and platelet tissue

    Elliott, J.M.; Kent, A.

    1989-07-01

    The human platelet contains a functional 5-hydroxytryptamine (5-HT) receptor that appears to resemble the 5-HT2 subtype. In this study, we have used the iodinated derivative (125I)iodolysergic acid diethylamide ((125I)iodoLSD) in an attempt to label 5-HT receptors in human platelet and frontal cortex membranes under identical assay conditions to compare the sites labelled in these two tissues. In human frontal cortex, (125I)iodoLSD labelled a single high-affinity site (KD = 0.35 +/- 0.02 nM). Displacement of specific (125I)iodoLSD binding indicated a typical 5-HT2 receptor inhibition profile, which demonstrated a significant linear correlation (r = 0.97, p less than 0.001, n = 17) with that observed using (3H)ketanserin. However, (125I)iodoLSD (Bmax = 136 +/- 7 fmol/mg of protein) labelled significantly fewer sites than (3H)ketanserin (Bmax = 258 +/- 19 fmol/mg of protein) (p less than 0.001, n = 6). In human platelet membranes, (125I)iodoLSD labelled a single site with affinity (KD = 0.37 +/- 0.03 nM) similar to that in frontal cortex. The inhibition profile in the platelet showed significant correlation with that in frontal cortex (r = 0.96, p less than 0.001, n = 16). We conclude that the site labelled by (125I)iodoLSD in human platelet membranes is biochemically similar to that in frontal cortex and most closely resembles the 5-HT2 receptor subtype, although the discrepancy in binding capacities of (125I)iodoLSD and (3H)ketanserin raises a question about the absolute nature of this receptor.

  20. Dosimetric parameters estimation using PENELOPE Monte-Carlo simulation code: Model 6711 a 125I brachytherapy seed

    The dosimetric parameters for characterization of a low-energy interstitial brachytherapy source 125I are examined. In this work, the radial dose function, g(r), anisotropy function F(r,?), and the absolute dose rate, ?, around 125I seed model 6711 have been estimated by means of the PENELOPE Monte-Carlo (MC) simulation code. The results obtained are in good agreement with the corresponding values recommended by TG-43 that are based in experimental and MC published results