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Sample records for 125i permanent implant

  1. Three-dimensional verification of 125I seed stability after permanent implantation in the parotid gland and periparotid region

    To evaluate seed stability after permanent implantation in the parotid gland and periparotid region via a three-dimensional reconstruction of CT data. Fifteen patients treated from June 2008 to June 2012 at Peking University School and Hospital of Stomatology for parotid gland tumors with postoperative adjunctive 125I interstitial brachytherapy were retrospectively reviewed in this study. Serial CT data were obtained during follow-up. Mimics and Geomagic Studio software were used for seed reconstruction and stability analysis, respectively. Seed loss and/or migration outside of the treated area were absent in all patients during follow-up (23–71 months). Total seed cluster volume was maximized on day 1 post-implantation due to edema and decreased significantly by an average of 13.5 % (SD = 9.80 %; 95 % CI, 6.82–17.68 %) during the first two months and an average of 4.5 % (SD = 3.60 %; 95 % CI, 2.29–6.29 %) during the next four months. Volume stabilized over the subsequent six months. 125I seed number and location were stable with a general volumetric shrinkage tendency in the parotid gland and periparotid region. Three-dimensional seed reconstruction of CT images is feasible for visualization and verification of implanted seeds in parotid brachytherapy

  2. 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)

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

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

  4. 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

  5. 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

  6. 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

  7. 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

  8. 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

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

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

  10. Clinical application of transperineal 125I-seed implantation guided by ultrasonography in prostate cancer

    Objective: To establish an optimal technological protocol, and to observe the short-term efficacy and morbidity of transperineal 125I-seed implantation guided by transrectal ultrasonography in prostate cancer. Method: Thirty-two patients were treated with transperineal 125I-seed brachytherapy guided by transrectal ultrasound. Among them 6 patients were treated with the seed implantation plus preor post-external beam radiotherapy (EBRT). Biochemical failure was defined as consecutive elevations of PSA level for three times during follow-up period and the biochemical progression-free was defined as biochemical control. Results: The pre- and post-implantation median serum PSA values of 14 patients were (52.14 ± 54.61) ng/ml and (4.26 ± 7.11) ng/ml, respectively (t=3.253, P=0.003). The biochemical control rate was 100%. The pre- and post-treatment median PSA values of 12 recurrent prostate cancer patients were (15.14 ± 20.80) ng/ml and (18.94 ± 35.25) ng/ml, respectively (t=-0.307, P=0.764). Their biochemical control rate was 75%. The pre- and post-implantation median PSA values of 5 patients with bone metastases were (120.03 ± 145.96) ng/ml and (75.53 ± 84.84) ng/ml, respectively (t=0.527, P=0.621). In 34.62% patients treated only with 125I-seed implication urinary complications were not experience and the incidences of Grade I, II, III, IV and V urinary side effects were 38.46%, 11.54%, 11.54%, 0 and 3.85%, respectively. The incidences of Grade I, II, III and IV urinary morbidity were 16.67%, 0, 0 and 16.67%, respectively for patients treated with seed implantation plus EBRT. Grade 1 rectal toxicity was noted in 3.12% patients. In 3.12% patients, one seed migration occurred. Conclusion: Transperineal permanent brachytherapy is safe, convenient, minimally invasive, with low urinary and rectal side effects. (authors)

  11. 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

  12. 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)

  13. 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

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

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

  15. Clinical efficacy of CT-guided 125I seed implantation therapy for advanced pancreatic cancer

    Objective: To discuss the clinical efficacy of CT-guided radioactive 125I seed implantation treatment for unresectable pancreatic cancer. Methods: Forty patients with inoperable pancreatic cancer were enrolled in this study, including 25 males and 15 females with an median age of 69 years (38-89 years). Treatment planning system (TPS) was used to reconstruct 3-dimensional images of pancreatic tumor and to define the quantity and distribution of 125I seeds. The radioactivity of 125I seeds was 0.5 - 0.8 mCi / seed. The seeds were implanted into pancreatic tumor under CT guidance at intervals of 1 cm and were kept away from vessels, pancreatic duct and other adjacent important organs. The tumor matched peripheral dose (MPD) was 60-140 Gy. The median amount of implanted 125I seeds was 36 (18-68) in number. CT scan was performed immediately after the procedure to check the quality of the seeds. In addition, 10 patients received concurrent chemotherapy with arterial infusion of gemcitabin and 5-fluororacil (5-Fu) for 3 to 4 therapeutic courses. Results: The median diameter of the tumors was 4.9 cm. The follow-up period was 2 to 28 months. After the treatment the refractory pain was significantly relieved (P 125I seed implantation is a safe, effective and minimally-invasive brachytherapy for unresectable pancreatic cancer with reliable short-term efficacy. It has an excellent anti-pain effect. The curative results can be further improved when chemotherapy is employed together. However, its long-term efficacy needs to be observed. (authors)

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

    Liangrong Shi

    2013-09-01

    Full Text Available Objective: To evaluate the safety and short-term effect of CT-guided 125I radioactive seed implantation on regional lymph node metastasis after gastrectomy. Methods: Twenty-three patients with regional lymph node metastasis after gastrectomy received CT-guided 125I radioactive seed implantation from June, 2007 to July, 2011 in our hospital. The overall activity and amount of radioactive seeds were calculated by simulating source distribution of radioactive seed implantation plan system before operation. 125I seeds were implanted under the guidance of CT. Effective rate was evaluated according to RECIST criterion, 1, 2 and 3 years of survival rates were calculated by life table method, the effect of relative factors on survival was tested by univariate COX model, and the survival differences between subgroups were compared to draw survival curve by log-rank method. Additionally, systemic therapies were given to 20 patients based on fluorouracil drugs. Results: No severe complications was observed in all study subjects with 14 complete remission (60.9 % , 5 particle remission (21.7 % and 4 progressive diseases (17.4 % , while 1, 2 and 3 years of survival rates as well as median survival time being (87±7 %,(47±11 % , (13±9 % and (22.1±5.1 months, respectively. Univariate COX analysis showed that the maximum diameter of tumor could badly influence the prognosis (χ2 = 9.752, P = 0.002, and the subgroups analysis relieved the significant difference (χ2 = 5.828, P = 0.016, log-rank test with 3 cm being the cut-off value. Conclusion: CT-guided 125I radioactive seed implantation has high local control rate with small trauma and slight complications.

  17. 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.

  18. 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

  19. CT guided radioactive seed 125I implantation in treating hilar hepatic tumor and metastatic lymph nodes

    Objective: To investigate the clinical value of CT guided radioactive seed 125I implantation in treating hilar hepatic tumor and metastatic lymph nodes. Methods: 32 patients with pancreatic cancer accepted CT guided radioactive seeds 125I implantation were enrolled in this study. The average tumor dimension was 4.2 cm. In this series, there were 8 cases of hepatocellular carcinoma, 12 cases of hilar cholangio carcinoma, 6 cases of hepatic metastasis and 6 of hepatic hilar tumor and metastatic lymph nodes. Among these patients, 14 cases had cholangiectasis and 22 cases had cirrhosis. Under CT guidance, 125I seeds of 0.6-0.9 mCi were implanted into the pancreatic cancer at a distance of 1.0-1.5 cm according to TPS. Results: Two cases died on account of metastasis and three died through liver function failure. Among CT followed-up of 32 patients in 2 months, 2 obtained CR, 20 obtained PR, 5 NC and 5 PD. The responsive rate was 68.8%. The side effects occurred during the procedure including pneumothorax in 1 case with lung compression less than 30%; 7 seeds migration in liver and 3 seeds in lung. WBC decreased slightly in 1 cases during 2 months follow up. No massive bleeding, biliary fistula, intestinal fistula, intestinal hemorrhage, acute pancreatitis, enterorrhagia and intra-abdominal abscess were encountered. Conclusions: CT guided radioactive seed 125I implantation procedure is a safe and effective method in treating hilar hepatic tumor and metastatic lymph nodes with good clinical effects of minimal damage and few complications. (authors)

  20. 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.)

  1. 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)

  2. 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.

  3. 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)

  4. 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)

  5. 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)

  6. 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)

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

    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

  8. Radiochemotherapy with interstitial implantation of 125I seeds and 5-FU slow-release seeds for recurrent thyroid cancer

    Objective: To investigate the combined treatment technological feasibility, efficacy with interstitial implantation of 125I seeds and 5-FU slow-release seeds for recurrent thyroid cancer. Methods: From March 2002 to December 2003, 9 cases of recurrent thyroid cancer were treated with radiochemotherapy. They were all patients with recurrent thyroid cancer after operation and radiation. The authors implanted alternately 125I seeds and 5-FU slow-release seeds by guiding of treatment planning system. The MPD of 125I seed implantation were 60-90 Gy. The mean 8 granules of 125I seeds and 5-FU 200 mg were used in every patient. Results: Fully operating procedure was accomplished for all the patients. No operating complication occurred. No displacement of 125I seeds was found by cervical X-ray. CT scan showed that the reduced size of tumor changed in different degree. The CR was 11.11%(1/9). The PR was 66.66%(6/9). The NC was 22.22% (2/9). Following up 8-26 months, all patients survived. Conclusion: Using radiochemotherapy with interstitial implantation of 125I seeds and 5-Fu slow-release seeds is safe, minimally invasive and effective for treatment of recurrent thyroid cancer

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

    The present study aimed to explore the safety profile and clinical efficacy of CT-guided radioactive seed implantation in treating local recurrent rectal carcinoma. 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). 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. CT-guided 125I seed implantation appeared to be a safe, useful and less complicated interventional treatment option for local recurrent rectal carcinoma

  10. 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)

  11. Treatment of Central Type Lung Cancer by CT Guided Percutaneous Implants of 125I Radioisotopes

    Xiaokun Hu; Mingyou Wang; Zhiguo Yang; Chundong Qiu; Dongfang Lü; Xiaodong Li; Taiyang Zuo

    2005-01-01

    OBJECTIVE To discuss the method, safety and effectiveness of the treatment for central-type carcinoma of the lungs by CT guided percutaneous implants of 125I radioisotopes in tissues.METHODS Twenty-two cases of central-type lung cancer located by plain and /or enhanced CT scans were retrospectively analyzed, among which 18cases were verified pathologically using a CT guided percutaneous puncture and biopsy before treatment. The CT guided treatment was conducted immediately after the pathological results were obtained. The number of the radioisotopes used was seven to 16. The intensities of radioactivity for 125I radioisotopes were 22, 26, 30 and 33 MBq per particle.The total intensity of radioactivity was 181 to 355 MBq. The puncture point was only one. The frequency for adjustment of needling direction was two to five times. The punctures were conducted through the anterior chest wall in eight cases, through the lateral chest wall in eight cases and thruogh the posterior chest wall in six cases. Six of the 22 cases were given intravenous chemotherapy.RESULTS Of the 22 cases, 20 were followed-up for more than one month, 16over two months, ten over three months and three cases for six months. In the 20 cases which were followed-up for one month, the diameters of the tumors were reduced by 50% or more in 18 cases, showed no change in two cases with none showing enlargement. In the 16 cases followed-up for more than two months, the diameters of tumors were reduced by 50% or more in 15cases, one case showed no change and none enlarged. In the ten cases with three months of follow-up, the tumor diameters were diminished by 50%or more in eight cases, showed no change in one case and enlarged in one case. In the three cases followed-up for six months, the diameters of tumors were reduced by 50% or more in all the cases. Of the 22 cases, atelectasis occurred in 12 before therapy. The lungs expanded again in nine cases in the follow-up after treatment. Symptoms after

  12. 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)

  13. 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)

  14. 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

  15. 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)

  16. 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)

  17. Effects of TPS calculation grid on dose calculation accuracy for 125I seed implantation

    Objective: To study the influence of TPS calculation grid on the dose calculation accuracy for 125I seed implantation. Methods: Ten verification plans were selected randomly. Calculating grids were modulated into four groups: 128 × 128, 96 × 96, 64 × 64 and 32 × 32. Under the conditions of same seeds number, location, activity and target volume, the doses resulting from every plan were calculated using TPS to obtain D90, V90, V100 and V150. Data were grouped into A, B, C and D by means of the calculating grid of 128 × 128, 96 × 96, 64 × 64 and 32 × 32. The percentage errors of four groups were calculated. Results: The arithmetic mean D90 of group A, B, C and D were (7 178.8 ± 2 237.7), (7 072.7 ±2 240.8), (6 889.1 ±2 305.5) and (6 351.0 ±2 515.7) cGy, respectively. The arithmetic mean of percentage errors of the four groups were (0.74 ± 0.6)%, (-0.89 ± 2.2)%, (-3.85 ± 4.7)% and (-10.46 ±4.8)% (F=8.95, P <0.05). The V90 of group A, B, C and D were (93.12 ± 0.32)%, (92.75 ±0.29)%, (91.87±1.28)% and (88.06 ±5.06)% (F=7.85, P<0.05). The V100 of group A, B, C and D were (90.21 ±0.14)%, (89.67 ±0.64)%, (88.68 ± 1.80)% and (84.10±6.56)% (F=6.64, P<0.05). The V150 of group A, B, C and D were (73.48 ±3.49)%,(72.66±3.96)%,(71.33±4.83)% and (65.41 ±9.49)% (F=3.90, P<0.05). Conclusions: The dose calculating accuracy of 125I seeds implantation is influenced significantly by TPS calculating grid. The calculating grid of 128 × 128 should be used as long as the calculating speed is not reduced. (authors)

  18. Safety evaluation in vicinity during and after 125I seeds implantation in head and neck region

    Objective: To measure the radiation dose during and after 125I seeds implantation in head and neck region, and to evaluate the radiation safety in the vicinity. Methods: Forty patients who had 125I seeds implanted in head and neck region were divided into two groups as facial and neck group as well as intra-oral group. The radiation doses were measured at the distance of 30 cm in three different directions during operation and at the distances of 30, 50, and 100 cm after operation when the patients opened and closed their mouth, respectively. Results: The radiation dose rate on the treatment side [(2.60±0.37) μSv] was higher than that on the other two sides [(0.28±0.05) and (0.15±0.03 μSv)] during the operation, with the statistical difference (t=25.62, 29.51, P0.05). On the treated side at all the distances of 30, 50, and 100 cm, the radiation dose rates were higher in the facial and neck group [(66.28±3.31), (35.06±3.05) and (1.72±0.17) μSv/h] than those in the intra-oral group [(52.46±3.54), (20.78±2.01) and (1.55±0.13) μSv/h], with the statistical difference (t=12.74, 15.51, 3.69, P<0.05). At the distance of 100 cm, the radiation dose rates were (1.72±0.17) μSv/h in facial and neck group, (1.55±0.13) μSv/h when which was safe for the public. Conclusions: Radiation exposure to the medical workers and the public from the patients is very low. It is easy to achieve the radiation safety by reducing the exposure time, increasing the distance and changing the exposure direction. (authors)

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

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

  20. 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)

  1. 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

  2. Comparison of methods for calculating rectal dose after 125I prostate brachytherapy implants

    Purpose: To compare several different methods of calculating the rectal dose and examine how accurately they represent rectal dose surface area measurements and, also, their practicality for routine use. Methods and Materials: This study comprised 55 patients, randomly selected from 295 prostate brachytherapy patients implanted at the Vancouver Cancer Center between 1998 and 2000. All implants used a nonuniform loading of 0.33 mCi (NIST-99) 125I seeds and a prescribed dose of 144 Gy. Pelvic CT scans were obtained for each patient ∼30 days after implantation. For the purposes of calculating the rectal dose, several structures were contoured on the CT images: (1) a 1-mm-thick anterior rectal wall, (2) the anterior half rectum, and (3) the whole rectum. Point doses were also obtained along the anterior rectal surface. The thin wall contour provided a surrogate for a dose-surface histogram (DSH) and was our reference standard rectal dose measurement. Alternate rectal dose measurements (volume, surface area, and length of rectum receiving a dose of interest [DOI] of ≥144 Gy and 216 Gy, as well as point dose measures) were calculated using several methods (VariSeed software) and compared with the surrogate DSH measure (SADOI). Results: The best correlation with SA144Gy was the dose volumes (whole or anterior half rectum) (R = 0.949). The length of rectum receiving ≥144 Gy also correlated well with SA144Gy (R ≥0.898). Point dose measures, such as the average and maximal anterior dose, correlated poorly with SA144Gy (R ≤0.649). The 216-Gy measurements supported these results. In addition, dose-volume measurements were the most practical (∼6 min/patient), with our surrogate DSH the least practical (∼20 min/patient). Conclusion: Dose-volume measurements for the whole or anterior half rectum, because they were the most practical measures and best represented the DSH measurements, should be considered a standard method of reporting the rectal dose when

  3. {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.)

  4. 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

  5. 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

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

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

  7. 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)

  8. 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)

  9. 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

  10. 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)

  11. 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)

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

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

  13. 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)

  14. Effects of 125I-Labeled Peptide Nuclear Acid Targeting Ki67 on the Growth of Implanted Human Renal Cell Carcinoma in Nude Mice

    JiacunChen; JunnianZheng; SongWu; HaibiaoLai; XiaoqingSun; JunjieLiu

    2004-01-01

    OBJECTIVE To investigate the potential of 125I-labeled anti-sense peptide nucleic acids (125I-AS-PNAs) to inhibit the expression of the Ki-67 gene and growth of implanted human renal carcinoma cells in nude mice.METHODS Anti-sense peptide nucleic acids (AS-PNAs) targeting the Ki67 gene were synthesized and labeled with 125I by the Chloraseptine-T method. Drugs including PNAs and 125I-AS-PNAs capsulated by cationic lipid were directly injected into tumors in nude mice. The Ki67 expression in tumors was detected by an immunohistochemical technique and Western blot. The apoptosis of tumor cells was detected by a TUNEL assay. Tumor volumes were measured every 3 days and tumor suppression rates were calculated at 12 days after treatment. Control groups were treated with AS-PNA, MMPNAs (mismatch PNAs) and 125I-Na.RESULTS The Ki67 expression rate of tumors treated by 125I-AS-PNAs [(15.3±1.8)%] was lower than that treated by AS-PNAs [(23.0±2.4)%] (P<0.01). The Ki67 protein production rate of tumors treated by 125I-AS-PNAs [(43.6±3.5)%] was lower than that treated by AS-PNAs [(59.7±2.3)%] (P<0.01 ). The apoptosis rate of tumors treated by 125I-AS-PNAs [(40.3±2.4)%] was higher than that treated by AS-PNAs [(31.1 ±2.0)%] (P<0.01). The volume of tumors treated by 125I-AS-PNAs [(330.4±57.8) mm3 ]was smallerthan that treated by AS- PNAs [(513.2±64.2 ) mm3] (P<0.01 ).CONCLUSION 125I-AS-PNAs targeted against the Ki67 gene have a greater inhibitory effect on the expression of the Ki67 gene and a larger apoptotic action on human renal carcinoma cells and can more efficiently inhibit tumor growth than AS-PNAs. 125I-AS-PNAs targeting the Ki67 gene may be a promising anti-sense/anti-gene radiotherapy method for treating renal cell carcinoma.

  15. 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)

  16. 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.

  17. 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

  18. 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)

  19. 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)

  20. 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)

  1. CT-guided iodine-125 seed permanent implantation for recurrent head and neck cancers

    To investigate the feasibility, and safety of 125I seed permanent implantation for recurrent head and neck carcinoma under CT-guidance. A retrospective study on 14 patients with recurrent head and neck cancers undergone 125I seed implantation with different seed activities. The post-plan showed that the actuarial D90 of 125I seeds ranged from 90 to 218 Gy (median, 157.5 Gy). The follow-up was 3 to 60 months (median, 13 months). The median local control was 18 months (95% CI, 6.1-29.9 months), and the 1-, 2-, 3-, and 5- year local controls were 52%, 39%, 39%, and 39%, respectively. The 1-, 2-, 3-, and 5- survival rates were 65%, 39%, 39% and 39%, respectively, with a median survival time of 20 months (95% CI, 8.7-31.3 months). Of all patients, 28.6% (4/14) died of local recurrence, 7.1% (1/14) died of metastases, one patient died of hepatocirrhosis, and 8 patients are still alive to the date of data analysis. CT-guided 125I seed implantation is feasible and safe as a salvage or palliative treatment for patients with recurrent head and neck cancers

  2. 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...

  3. 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

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

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

    2007-07-01

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

  5. 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

  6. 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)

  7. 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

  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. 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

  10. Permanent Breast Seed Implant Dosimetry Quality Assurance

    Keller, Brian M., E-mail: Brian.Keller@sunnybrook.ca [Department of Medical Physics, Sunnybrook Health Sciences Center, Toronto, ON (Canada); Department of Radiation Oncology, University of Toronto, Sunnybrook Health Sciences Center, Toronto, ON (Canada); Ravi, Ananth [Department of Medical Physics, Sunnybrook Health Sciences Center, Toronto, ON (Canada); Sankreacha, Raxa [Carlo Fidani Regional Cancer Center, Mississauga, ON (Canada); Pignol, Jean-Philippe [Department of Radiation Oncology, University of Toronto, Sunnybrook Health Sciences Center, Toronto, ON (Canada)

    2012-05-01

    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 V{sub 90}, V{sub 100}, V{sub 150}, and V{sub 200} 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 V{sub 100} changed from 85.6% to 88.4% (p = 0.004) and the mean V{sub 200} changed from 36.2% to 48.3% (p < 0.001). Skin toxicity was associated with maximum skin dose (p = 0.014). Conclusions: Preplanning dosimetry should aim for a V{sub 90} of approximately 100%, a V{sub 100} between 95% and 100%, and a V{sub 200} 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 Multiplication-Sign 1-cm{sup 2} surface area, should be limited to 90% of the

  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 4π 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. Oblate band in 125I

    The iodine isotopes belonging to the transitional region with Z ≥ 50 and N ≤ 82, have been the subject of extensive theoretical and experimental research as they exhibit various coexisting structures. The levels of 125I were studied via 123Sb (α, 2nγ) 125I fusion-evaporation reaction at 30-MeV beam energy

  14. Iodine-125 Seed Implantation (Permanent Brachytherapy for Clinically Localized Prostate Cancer

    Saika,Takeshi

    2008-02-01

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

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

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

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

    Neha Mall; B Dhanasekar; I. N. Aparna

    2011-01-01

    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 r...

  17. 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.

  18. 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

  19. The effect of the radial function on I-125 seeds used for permanent prostate implantation

    The purpose of this study was to evaluate the integrity of eight commercially-available low-activity Iodine-125 (125I) seeds for their radial function g(r) and its effect on the dose delivered to the adjacent critical structures when used in permanent prostate implants (PPI). Ten previously treated patients were retrospectively used in this comparison. The Amersham Health Oncura seed was used to peripherally design an isodose distribution with urethral and anterior rectal wall sparing. Plan criteria included minimum coverage of 144 Gy to the planning target volume (PTV), ≤ 70% dose to 150% of the PTV volume (V150-PTV), and the quantity of needles ≤ 70% of the size of the PTV, in cc. Upon completion of the Oncura plan, the seed type was changed and the activity was adjusted until the V100-PTV for each of the other 7 seed types matched the V100-PTV defined by the Oncura seed. Computed tomography (CT)-based postimplant dosimetry was used to determine the dose to 40% (D40) of the bulb of the penis (in Gy). Dose-volume histograms (DVH) were used to evaluate the differences to V100 (in %) and D40 (in Gy) of the anterior rectal wall and bulb of the penis, and V100 (in %) of the urethra. The data was tabulated. Radioactive 125I sources included in this study were 125I Source 2301 (Best); I-Plant (MedTech), IoGold (Mentor), Oncura (Amersham Health), ProstaSeed (UroCor), SelectSeed (Nucletron), SourceTech (Bard), and Symmetra (UroMed). The sizes of the PTV for the 10 patients ranged from 18.82 cc to 48.99 cc. The Oncura seed was used as the reference seed and all other seed types were normalized to it for data comparison. It was determined that the dose rate constant (xwedge) and anisotropy factor (phi) contribute to the activity needed to achieve comparable V100-PTV doses, but a strong dependence on the radial function g(r) was found to effect the doses to the critical structures studied. Values of g(r) at 4 cm were calculated and the IoGold and SourceTech seeds were

  20. Nuclear lesions produced by 125I decay

    125I decay induced DNA damage was investigated in Chinese hamster ovary (CHO) cells which had incorporated 125I-iododeoxyuridine (125IUdR) into their DNA. 125I decays were accumulated in frozen cells. DNA strand breaks produced by low numbers (0--1,200 decays per cell) of 125I decays were assayed using the alkaline unwinding technique and the alkaline filter elution technique. Approximately 300 125I decays reduced the relative damage to 50%. DNA protein cross links were not detected after accumulation of 125I decay. The production of DNA double strand breaks by 125I decay was assayed by the neutral filter elution technique at pH 9.6 and 7.2 after accumulating 100--5,000 decays per cell. No alkali labile lesions were detected. Approximately 3,000 125I decays were required to reduce the mean value of the fractions to 50%. In all the assays, DNA damage induction data were fit to a straight line by regression analysis except at very low numbers of accumulated 125I decays where an initial drop in the fraction of DNA retained on the filter was observed. This drop suggests multiple chromatin fragmentation is produced by 125I decay

  1. 125I粒子植入对面神经超微结构影响的动物实验%Ultrastructural study on the facial nerve of rabbit after 125I seed implantation

    左健; 宋铁砾; 鞠向群; 郑磊; 蔡志刚; 张建国

    2011-01-01

    目的 探讨 125I放射性粒子不同处方剂量近距离照射对家兔面神经超微结构的影响,旨为临床提供参考.方法 将大耳白兔54只随机分为3个实验组:40 Gy组、80 Gy组、120 Gy组,每组18只动物;每只动物自身对照,将 125I粒子植入一侧腮腺区面神经周围,另一侧作为对照植入粒子空壳.每组分别于2、4、6个月时取面神经干做透射电镜观察.结果 对照组:术后2、4、6个月均可见面神经轴膜连续、轴膜下轻度水肿,髓鞘局部松散.实验组:术后2个月均可见面神经轴膜下水肿、髓鞘松散,其中80 Gy组可见巨噬细胞和新生神经纤维,120 Gy组可见板层分离及新生神经纤维;4个月均可见面神经板层分离、髓鞘松散,其中40、80 Gy组可见胶原增生及轴膜下水肿; 6个月均可见新生神经纤维、髓鞘松散,其中80、120 Gy组可见板层分离、轴膜下水肿.结论 家兔面神经在接受40、80及120 Gy 125I照射后,面神经超微结构存在一定的损伤,面神经受照射剂量越大损伤程度越重;但在120 Gy 125I照射6个月后,髓鞘与轴突的完整性和连续性仍基本保持.%Objective To investigate the ultrastructural variation of the facial nerve of rabbit with different dosage of 125I seed brachytherapy. Methods Fifty-four big ear rabbits were divided into 3 groups randomly and given 40 Gy, 80 Gy, 120 Gy respectively. Radioactive seeds were implanted in one side of parotid gland, the other side was implanted with vacant shell as a control group. The facial nerves were obtained 2, 4, 6 months respectively after operation and the histological ultrastructural changes observed by electromicroscope. Results In the control group,epineurium was continuous, there was slight pitting edema under the epineurium, and axonal myelin was loose. In the test groups, there was slight pitting edema under the epineurium, and axonal myelin sheath was loose at 4th month. Macrophage and regenerated fibers were

  2. 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. METHO...

  3. 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

  4. 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)

  5. 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

  6. 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)

  7. Dual-chamber implantable cardioverter-defibrillator. Is it useful in patient with permanent atrial fibrillation?

    Porres-Aracama, José M; Cerezuela, José Luis; García-Urra, Francisco; Luque-Lezcano, Oscar; Herrero, Vicente

    2016-08-01

    In patients with permanent atrial fibrillation (AF) and implantable cardioverter-defibrillator (ICD) implant indication, a single-chamber device is the choice because AF does not provide interesting information for the treatment. It is very unusual to find patients with permanent AF that coexist with atrial tachycardia with various degree of Atrioventricular block. PMID:27525075

  8. 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)

  9. 125I decay in synthetic oligodeoxynucleotides

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

  10. Current research and progress of radioactive 125I seed in the treatment of malignant tumor

    Radioactive 125I seed implantation has been paid more and more attention and studied by national and international scholars due to its minimal invasivity, high local tumor control rate and low complications. In the clinical treatment, to achieve the best treatment effect, the clinician should minimize the risk of possible 125I related complications. Making an accurate implantation plan by using the type -B ultrasonic and CT technique appropriately is essential. In this paper, we summarized that the application status of the 125I seed implantation technique in the treatment of malignant tumor. We also discussed the safety of its clinical applications. This review can provide a reliable basis for future standardized seed implantation treatment for malignant tumors. (authors)

  11. 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.

  12. Renal catabolism of 125I-glicentin

    The renal catabolism of 125I-glicentin has been studied in vivo by the disappearance of this peptide from the plasma of bilaterally nephrectomized, ureteral-ligated, or normal rats and by using tubular microinfusion techniques. In addition the catabolism of glicentin by the isolated, perfused kidney has been studied. Results from in vivo studies demonstrated that half-disappearance time was lower in control (59.5 +/- 1.8 min) than in bilaterally nephrectomized rats (97.2 +/- 2.6 min), and this value was significantly higher than that of ureteral-ligated animals (83.2 +/- 1.1 min, P less than 0.005). Microinfusion experiments revealed that when 125I-glicentin was injected into the proximal tubule, no trichloroacetic-precipitable radioactivity was recovered in the urine, whereas most of inulin injected was recovered. By contrast most of the 125I-glicentin injected into the distal tubule was recovered in the urine. In isolated kidney experiments, organ clearance rate of 125I-glicentin averaged 0.88 +/- 0.10 ml/min, a value significantly higher than that of glomerular filtration rate (0.72 +/- 0.06 ml/min, P less than 0.005, paired data), and both parameters showed a close linear relationship (r = 0.90). Urinary clearance of glicentin was negligible. These results demonstrate that the kidney plays a major role in the catabolism of glicentin, mainly by glomerular filtration and tubular catabolism. The site of tubular catabolism appears to be the proximal tubule. Peritubular uptake was minimal

  13. 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

  14. Current status and prospect of 125I production

    125I nuclide is widely applied in many fields such as medical and biological research, radioimmunoassay, brachytherapy of cancers, etc. The processes and current status of 125I production, domestic market demand, and the prospect of 125I nuclide production with the existing reactors in China were briefly introduced. (author)

  15. 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

  16. Implant-supported prostheses versus conventional permanent and removable dentures

    Koszuta Agnieszka

    2014-06-01

    Full Text Available Social, economic and technological progress results in an increasing range of treatment and rehabilitation methods for patients with partial or complete edentulism. The role of the dentist is to inform the patient about the full range of available missing teeth treatment options leading to complete rehabilitation of the masticatory organ in agreement with the patient’s aesthetic and functional expectations. The aim of the paper was to identify the type of prostheses used by patients before opting for implantsupported teeth replacements, according to the patients’ age, sex, marital status, place of residence and education. The study covered 464 patients, women and men, aged 20-74, treated with dental implants. The patients answered questions in an anonymous questionnaire. The influence of the prosthetic replacement type according to age and marital status was highly statistically significant, whereas it was statistically significant according to sex, place of residence and education. The female respondents who previously used tissue-borne complete or partial dentures opted for implant treatment more frequently. The respondents younger than 40 and between 40-60 years of age who did not previously used any prosthetic replacements opted for implant treatment more frequently. The respondents who did not use any prosthetic replacements decided to undergo implant treatment most frequently, regardless of their marital status, education and place of residence. The patients opted for implant treatment to improve their quality of life, despite the high cost of such therapy.

  17. 125I Measurements for Occupational Exposure Assessment

    Silva, L.; Pinhão, N. R.

    2008-08-01

    Whenever there is a risk of occupational exposure to dispersible radioactive material, it is necessary to have a monitoring program to assess the effective dose arising from the intake of radionuclides by workers. In this paper we present our experience in bioassay measurements of 125I in urine samples of workers using high resolution gamma spectrometry. For a 24-hour excretion period, we found activity values of the order of one Bq and estimated the committed effective doses to be less than one μSv. Although very small, these values led to a re-evaluation and improvement of the laboratory safety conditions. We discuss the calibration procedure followed for the activity measurements, the estimation of the uncertainty in the excreted activity, the calculation of detection and quantification limits and estimation of performance indicators. Aspects regarding the spectral analysis, true coincidence summing and matrix effects are also considered.

  18. CT-guided percutaneous perineal permanent implants with I-125

    The authors have combined the principles of CT-guided percutaneous biopsy and biplane fluoroscopy in performing outpatient percutaneous pelvic implantations of I-125 seeds for the treatment of unresectable or recurrent tumors of the pelvis, utilizing a transperineal approach. The technique allows implantations up to a depth of 16 cm from the perineum. No complications have been encountered. Twelve procedures have been performed. The types of tumor treated include five cases of recurrent carcinoma of the rectum, five cases of unresectable carcinoma of the prostate, one case of recurrent sarcoma of the rectum, and one case of adenocarcinoma of unknown origin involving the pelvic wall

  19. 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

  20. 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)

  1. 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)

  2. 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).

  3. Optimization of 125I ophthalmic plaque brachytherapy

    Episcleral plaques containing 125I sources are often used in the treatment of ocular melanoma. Within four years post-treatment, however, the majority of patients experience some visual loss due to radiation retinopathy. The high incidence of late complications suggests that careful treatment optimization may lead to improved outcome. The goal of optimization would be to reduce the magnitude of vision-limiting complications without compromising tumor control. We have developed a three-dimensional computer model for ophthalmic plaque therapy which permits us to explore the potential of various optimization strategies. One simple strategy which shows promise is to maximize the ratio of dose to the tumor apex (T) compared to dose to the macula (M). By modifying the parameters of source location, activity distribution, source orientation, and shielding we find that the calculated T:M ratio can be varied by a factor of 2 for a common plaque design and posterior tumor location. Margins and dose to the tumor volume remain essentially unchanged

  4. 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

  5. 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)

  6. 组织间125I放射粒子植入治疗头颈部恶性肿瘤颈部淋巴结转移的临床应用%Clinical application of interstitial implantation of 125I radion in the treatment of cervical lymph node metastasis of head and neck malignancy

    李福生; 黄海; 徐绍年; 杜振广; 王亮

    2014-01-01

    目的:探讨组织间125I放射粒子植入治疗头颈部恶性肿瘤颈部淋巴结转移的价值。方法对21例头颈部恶性肿瘤颈部淋巴结转移患者进行125I放射粒子植入治疗,术前行TPS(computer-based treatment planning system)计划、根据计划在CT引导局部麻醉下行颈部淋巴结转移瘤125I放射粒子植入、术后复查CT进行质量验证。根据NRS评分对术前术后患者局部疼痛进行评估,按WHO标准对局部肿瘤控制疗效进行评价。结果随访7~29个月,21例患者均成功行手术治疗,术后3个月复查,完全缓解3例(14%)、部分缓解15例(71%)、病变稳定2例(10%)、病变进展1例(5%);6个月、1、2年的局部控制率(局部肿瘤无进展)分别为:84%、65%、39%;NRS疼痛评分术前、术后3个月、6个月分别为:(7.62±0.92)分,(2.81±0.68)分,(2.14±0.39)分(P<0.05)。3例患者术后出现发热,未超过38.5℃,3~5 d内恢复正常;3例皮肤黏膜1级急性放射性损伤,2例皮肤黏膜2级急性放射性损伤,无3~5级皮肤黏膜急性放射性损伤。所有患者未发生大出血、急性肺栓塞、窦道等严重并发症。结论组织间125I放射粒子植入治疗头颈部恶性肿瘤颈部淋巴结转移创伤小,并发症少,局部控制率较高,疼痛缓解明显,为不能手术的晚期头颈部恶性肿瘤颈部淋巴结转移的患者提供了一种新型治疗手段。%Objective To explore the value of interstitial implantation of 125I radion in the treatment of cervical lymph node metastasis of head and neck malignancy. Methods There were 21 patients with cervical lymph node metastasis of head and neck malignancy received 125I radion implantation. Computer-based treatment planning system (TPS) was operated before the surgery, and implantation of 125I radion was conducted under CT guidance and local anesthesia. Postoperative CT review was used for quality verification. Numerical rating scale (NRS) was used to assess patients

  7. 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

  8. 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

  9. 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)

  10. Online gamma-camera imaging of 103Pd seeds (OGIPS) for permanent breast seed implantation

    Permanent brachytherapy seed implantation is being investigated as a mode of accelerated partial breast irradiation for early stage breast cancer patients. Currently, the seeds are poorly visualized during the procedure making it difficult to perform a real-time correction of the implantation if required. The objective was to determine if a customized gamma-camera can accurately localize the seeds during implantation. Monte Carlo simulations of a CZT based gamma-camera were used to assess whether images of suitable quality could be derived by detecting the 21 keV photons emitted from 74 MBq 103Pd brachytherapy seeds. A hexagonal parallel hole collimator with a hole length of 38 mm, hole diameter of 1.2 mm and 0.2 mm septa, was modeled. The design of the gamma-camera was evaluated on a realistic model of the breast and three layers of the seed distribution (55 seeds) based on a pre-implantation CT treatment plan. The Monte Carlo simulations showed that the gamma-camera was able to localize the seeds with a maximum error of 2.0 mm, using only two views and 20 s of imaging. A gamma-camera can potentially be used as an intra-procedural image guidance system for quality assurance for permanent breast seed implantation

  11. 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

  12. 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)

  13. Defect in Lung Perfusion and Ventilation Scanning of Patients with Permanent Transvenous Implantable Pacemaker

    Matsuura, Yuichiro; Tamura, Mutsuo; Yamashina, Hideki; Higo, Masanori; Fujii, Takanori; Shimamoto, Hiroyuki; Kinoshita, Hirofumi

    1984-01-01

    Lung perfusion and ventilation scanning with 99mTc-MAA and 81mKr-Gass were studied in 138 patients with permanent transvenous implantable pacemaker. There were observed segmental or subsegmental defects in lung perfusion and ventilation scanning which were considered to be probably lung embolism of 47 cases. The incidence of lung embolism was high during the first postoperative 6 months, and it also increased progressively with aging. The patient with ischemic heart disease or va...

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

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

    2014-01-15

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

  15. 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

  16. Synthesis and application of PLGA labeled with 125I

    2006-01-01

    The weight loss in vivo degradation of poly (lactide-co-glycolide) (PLGA) radiolabeled with 125I was investigated. PLGA with molecular weight (Mw) of 84000(LA/GA=85/15) were labeled with 125I in the chloroform media by circularly heating and round films of about 15 mm in diameter were formed. The composition and Mw of the 125I-PLGA were characterized by 1H-NMR and viscosimeter. The weight loss of this copolymer in vitro and in vivo degradation was quantified by determining radioactivity of materials. The results indicated that PLGA exhibited significantly faster degradation in vivo than that of in vitro conditions.

  17. 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)

  18. 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

  19. 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

  20. Personal monitoring in the radiochemical production of 125I

    To estimate occupational exposure during the radiochemical production of 125I, measurements, of 125I deposited in the thyroids of personnel were carried out, beginning in 1986. Each measurement was designed to control later values, which were based on: the thyroid dose accumulated during the year prior to the measurement and during the monitoring period, the committed annual thyroid dose assessed during 240 days before the measurement, and the dose that would be received after complete decay of the measured activity of 125I in the thyroid. Due to the improvement in safety in the production process, quarterly thyroid doses to personnel decreased approximately three-fold during the first year of monitoring. Data on individual quarterly 125I thyroid content and doses over 1.5 years of control for 20 workers are presented. Average annual thyroid doses of personnel varied from 15 to 30 mSv.y-1 in 1987-1992. (Author)

  1. 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

  2. 125I-labelled cobalamin derivative compatible with intrinsic factor

    A 125I-labelled derivative of cobalamin (vitamin B12) is described which is compatible with intrinsic factor in binding assays. The derivative, [125I]cyanocobalamin-d-iodohistamide, can be readily prepared with a specific activity of 1400 Ci/g. Used as a substitute for [57Co]cyanocobalamin in binding assays, the new derivative can reduce counting times and decrease costs in such assays. (Auth.)

  3. 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...

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

    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. (note)

  6. Preparation of 5-Iodo-2'- deoxyuridine labelled with 125 I

    5-Iodo-2'-deoxyuridine (IUdR), an analogue of thymidine is taken up by the proliferating cells during DNA synthesis. When IUdR is labelled with 125 I, due to Auger electrons from 125 I, this analogue of thymidine is very effective in cell destruction when is internalized. Recently, radioiodinated (125 I and 123 I) IUdR is considered a potential therapeutic agent, for treatment of cancer.125 I-IUdR was prepared by direct radioiodination of 2'-deoxyuridine (UdR), using chloramine T method. The radioiodination reaction was studied by varying the reaction parameters such as temperature and reaction time. The yield was improved by heating the reaction mixture to 65 deg. C for 10 min. Purification of 125 I-IUdR was carried out by gel filtration over a Sephadex G 25 column using 0.05 M citrate buffer (pH = 6). The yield of the reaction as well as the radiochemical purity were determined by paper electrophoresis using Whatman chromatography paper No.1, 0.05 M phosphate buffer at 13 V/cm. The analyse time was 1 h. The yield of radioiodination reaction was ≅70% and the radiochemical purity of 125 I-IUdR prepared by this method was: 91-92%. (authors)

  7. The factor analysis of the incidence of pneumothorax after CT-guided 125I radioactive seed implantation for lung cancer%CT引导下125I粒子植入治疗肺癌术后气胸发生率的相关因素分析

    霍小东; 杨景魁; 闫卫亮; 郑广钧; 柴树德; 孟娜; 杨瑞杰; 王俊杰

    2014-01-01

    Objective To analyze the impact factors of incidence of pneumothorax after CT guided puncture with radioactive 125I seed implantation in lung cancer patients.Methods 821 cases with lung cancer were treated with CT-guided percutaneous with radioactive particles implantation.198 cases of pneumothorax patients were collected.The impact factors of incidence of pneumothorax were analyzed by parallel unconditioned logistic regression.Results 24.1% (198/821) of cases had pneumothorax after CT guided puncture.Single variate analysis showed that the incidence of pneumothorax was ralated with seven factors,such as patients with the average depth of implanted needle,whether patients with COPD(chronic obstructive pulmonary diseases),atelectasis,implantation pin number and operation time,puncture angle,and the diameter of the tumor(x2 =10.293,11.463,5.310,8.868,13.348,9.326,16.504,P <0.05).176 patients of intercurrent COPD with postoperative pneumothorax suffered from 65 cases.The cases of distance between the chest wall and needle less than 6 cm(205 cases),8-12 cm(378 cases)and greater than 12 cm (238 cases),the postoperative pneumothorax occurred in 29 (14.1%),98 (25.9%),71 (29.8%)cases,respectively.The number of needles were less than 5(183 cases),5-10 (408 cases),more than 10 (230 cases),the postoperative pneumothorax occurred in 31 (16.9%),92 (22.5 %),75 (32.6%),respectively.The surgery time was less than 10 min(198 cases),10-20 min(412 cases)and more than 30 min(211 cases),the postoperative pneumothorax occurred in 27(13.6%),101 (24.5%),70(33.2%) respectively.19 cases(14.4%) with COPD (132 case) suffered from pneumothorax.The multivariate logistic regression analysis showed that the prior four factor were risk factors of pneumothorax (OR =1.676,2.147,1.827,2.368,P <0.05),and the last one is protective factor(OR =0.367,P < 0.05).Conclusions COPD disease history,long distance between lesion and chest wall,plenty of needles surgery time can affect

  8. 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

  9. Dosimetric results in implant and post-implant and low rate in brachytherapy prostate cancer with loose seeds and attached; Resultados dosimetricos en el implante y post-impante en braquiterapia de baja tasa en cancer de prostata con semillas sueltas y unidas

    Juan-Senabre, X. J.; Albert Antequera, M.; Lopez-Tarjuelo, J.; Santos Serra, A.; Perez-Mestre, M.; Sanchez Iglesias, A. L.; Conde Moreno, A. J.; Gonzalez Vidal, V.; Beltran Persiva, J.; Muelas Soria, R.; Ferrer Albiach, C.

    2015-07-01

    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)

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

    Armando Gardini

    2012-01-01

    Full Text Available Apical ballooning syndrome, also called takotsubo cardiomyopathy, has been recently reported. It may mimic acute myocardial infarction and is typically observed in postmenopausal women after stressful events. A 75-year-old female after permanent dual chamber pacemaker implant complained of chest pain with repolarization alterations suggesting acute myocardial ischemia. Echocardiography showed a left ventricle with akinesia of the apical portions and reduced global systolic function. The patient was treated with antithrombotic agents and intravenous nitrates. No coronary lesions were found at angiography. At ventriculography, a typical takotsubo-like shape of the left ventricle was observed. The clinical and echocardiographic picture normalized at discharge.

  11. 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)

  12. Nursing care of patients with prostate cancer accepting permanent 125I radion implantation treatment%125I放射性粒子永久植入治疗前列腺癌的护理

    郭红霞; 郝海龙

    2010-01-01

    @@ 前列腺癌是中老年男性生殖泌尿系统常见的恶性肿瘤.我国前列腺癌的发病率与欧美比较相对较低,但呈逐渐上升趋势[1].1983年美国Charyulu发明经会阴超声引导治疗前列腺癌技术,奠定了近代放射性粒子治疗前列腺癌的基础[2].与传统的前列腺癌的治疗方法相比,它具有创伤小、出血少、疗效好等优点[3].我院2004年1月-2009年1月采用经直肠超声(TRUS)引导下125I粒子植入术治疗前列腺癌病人31例,疗效较好.现将护理总结如下.

  13. Dosimetry of ophthalmic applications using 125I seed sources

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

  14. Computer assisted treatment planning for 125I ophthalmic plaque radiotherapy

    This paper describes a computer program for planning the treatment of ocular tumors with 125I plaques. The program permits the input of the tumor configuration into a model eye and facilitates the viewing of the relative geometry of the tumor and various eye structures in different perspectives. Custom-designed 125I plaques can be localized onto the globe, and dose distributions can be calculated and superimposed on the eye structures in any plane or on the inner eye surface. The program allows efficient evaluation of the plaque design in terms of radiation dose distribution relative to the tumor and critical structures

  15. 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

  16. Stereotactic iodine-125 brachytherapy for brain tumors: temporary versus permanent implantation

    Stereotactic brachytherapy (SBT) has been described in several publications as an effective, minimal invasive and safe highly focal treatment option in selected patients with well circumscribed brain tumors <4 cm. However, a still ongoing discussion about indications and technique is hindering the definition of a clear legitimation of SBT in modern brain tumor treatment. These controversies encompass the question of how intense the irradiation should be delivered into the target volume (dose rate). For instance, reports about the use of high does rate (HDR) implantation schemes (>40 cGy/h) in combination with adjuvant external beam radiation and/or chemotherapy for the treatment of malignant gliomas and metastases resulted in increased rates of radiation induced adverse tissue changes requiring surgical intervention. Vice versa, such effects have been only minimally observed in numerous studies applying low dose rate (LDR) regiments (3–8 cGy/h) for low grade gliomas, metastases and other rare indications. Besides these observations, there are, however, no data available directly comparing the long term incidences of tissue changes after HDR and LDR and there is, furthermore, no evidence regarding a difference between temporary or permanent LDR implantation schemes. Thus, recommendations for effective and safe implantation schemes have to be investigated and compared in future studies

  17. 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

  18. Carbon cartridge standards for 125I and suggested applications.

    Tries, M A; Ring, J P; Chabot, G E

    1997-09-01

    Carbon cartridge standards were prepared to assess the activity of 125I incident on, and adsorbed in, cartridge samples during air sampling. Each cartridge standard consisted of an 125I-spiked filter paper at a known depth, ranging from 0 to 19 mm, embedded in approximately 34 g of 20-30 mesh activated carbon contained within a 6.35 cm diameter by 2.22 cm deep metal cartridge with screened openings. The total counting efficiency values range from 17.8 to 20.8% for cartridges counted at 3.2 mm from a thin-crystal NaI(Tl) detector. The standards were analyzed using a front/back counting technique, and fitting functions were developed relating the front/back net counts ratio and counting efficiency to the 125I depth of burial. A method for determining sample activity that accounts for exponential radioiodine loading in cartridge samples is compared to a less complicated technique that assumes all the radioiodine is located at an equivalent depth of burial that is based on the sample front/back net counts ratio. In addition, methods are presented for determining airborne 125I activity for constant and variable concentrations. Variable concentrations are assumed to occur in a fume hood duct by one or more bulk releases as a result of iodinations that are performed during a given sampling interval. The two methods are shown to have maximum relative deviations ranging from -16 to +16%. PMID:9287093

  19. Radiotoxicity of intracellular 67Ga, 125I and 3H

    L1210 leukaemia cells were labelled with various doses of 67Ga-citrate, 3H-thymidine, or 125I-iododeoxyuridine to evaluate the cytocidal effects of the intracellular decay of the three radionuclides. Based on radioisotope incorporation data, cellular dimensions, and intracellular radioisotope distributions (3H and 125I intranuclear, 67Ga cytoplasmic) the rates of deposition of cellular, nuclear, and cytoplasmic energy were calculated. In terms of energy absorption/cell, 67Ga (LD50: 2250 keV/hr; 69 rad/hr) was much less toxic than either 3H (LD50: 325 keV/hr; 10 rad/hr) or 125I (LD50: 50 keV/hr; 1.5 rad/hr). In terms of energy absorption/nucleus, 67Ga and 3H produced almost identical effects (LD50: 230 versus 255 keV/hr; 22.2 versus 24.6 rad/hr), but 125I remained much more toxic (LD50: 40 keV/hr; 3.9 rad/hr). (author)

  20. 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

  1. [Permanent endocardiac electrostimulation. Considerations on 511 implantations and reimplantations in 7 years of practice].

    Mangiameli, S; Circo, A; Vanaria, D; Lombardo, D; Scalisi, A; Genovese, G; Galassi, A

    1977-06-30

    Permanent pacemakers were implanted and reimplanted in a total of 511 patients (mostly men) during a period of about 7 yr. Mean age was 67.9 yr. The cephalic route was used in nearly every case, with subclavicular implantation of the generator. Mean hospital stay was 7.6 days. Ventricular inhibition pacemakers were used in over 84% and fixed-frequency models in 7%. Mean pacemaker life was 24.1 months, with longer periods in the last months of the period of observation. The evaluation of battery run-down and recent and long-term complications is discussed, together with a particular type of decubitus of electrolytic origin. Hospital mortality was 2%. Survival was 91% at 1 yr and 54% at 6 yr. Emphasis is placed on the fact that subjects continue to be heart patients. Their well-being depends on psychological and general medical care, together with help from their, families and society, quite apart from cardiological attention. PMID:876509

  2. Scintillation proximity radioimmunoassay utilizing 125I-labeled ligands

    A unique type of radioimmunoassay is described that does not require centrifugation or separation. Microbeads containing a fluorophor are covalently linked to antibody. When an 125I-labeled antigen is added it binds to the beads and, by its proximity, the emitted short-range electrons of the 125I excite the fluorophor in the beads. The light emitted can be measured in a standard scintillation counter. Addition of unlabeled antigen from tissue extracts displaces the labeled ligand and diminishes the fluorescent signal. Application of scintillation proximity immunoassay to tissue enkephalins, serum thyroxin, and urinary morphine is described. Applications of the principle to study the kinetics of interaction between receptors and ligands are discussed

  3. Preparation of 19 iodocholesterol labelled with 125I

    A new method of synthesis of 19-iodocholesterol labelled with 125I 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 appropriate for clinical investigations and in the diagnosis of disturbances of the suprarenal glands. (author). 2 figs., 9 refs

  4. 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

  5. Production of 125I seed sources for brachytherapy uses

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

  6. 125I-interleukin-8 radiolabelling and in vivo distribution

    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, the authors labelled IL-8 with 125I using Bolton-Hunter reagent, and the distributions in mice at 5 min, 30 min, 1h, 6h and 24h after injection of 125I-IL-8 were measured. The blood clearance curve was obtained and fitted with the two-compartment model. The results showed that 125I-IL-8 was obtained with a labeling efficiency of 12.2% ± 6.5% and a radiochemical purity of 91.4% ± 6.5%. Its specific activity was 14.8 kBq/μg IL-8. A fast phase half-life T1/2α of 0.32 h and a slow phase half-life T1/2β of 8.01 h were calculated from the blood clearance curve. The uptakes of radioactivities in kidneys and lung had 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 were 12.05%ID/g and 8.97%ID/g as the maximum at 5 min after injection. The clearance in blood and other organs was fast. Except for kidneys and lung, 125I-IL-8 was less than 1%ID/g 24 h after administration. It is concluded that 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 the subjects necessary to be further investigated. (authors)

  7. 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)

  8. 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)

  9. 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

  10. 125I Labelling of Protein Using Immobilized Enzyme

    For an effective solid-phase labelling of protein with 125I, studies on the immobilization of lactoperoxidase (LPO) on the inner wall of polystyrene tubes were carried out. Labelling of bovine serum albumin (BSA) and insulin was also practiced using the LPO immobilized tubes. The immobilized enzyme of about 2.5 μ g/tube was sufficient for small scale labelling since the results of radio-paper chromatography of the labelling mixture of insulin indicated that the yields were sufficiently high (80%) even in the reactions conducted at room temperature for 60 sec. The results of the Sephadex column chromatography indicated that the labelled products were not contaminated with LPO-125I, and the radiochemical purity of the products was more than 90%. In considering the general trend that the 125I labelled protein obtained by using LPO maintains its intactness better than those obtained by using chloramine-T, together with the tendency of yield enhancing with increase of reactants-concentration, the LPO immobilized tube method is estimated to be one of the simple methods of labelling. The product might be applicable without further purification.

  11. 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

  12. 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

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

    Purpose: The objective of this report is to re-evaluate the role of the Anderson nomograms in treatment planning for permanent prostate implants. The incentive for revisiting this topic concerns three issues: (1) Although nomograms continue to be used in many centers for ordering seeds, few centers use them during treatment planning; (2) Whereas nomograms were designed to deliver a minimum peripheral dose for a uniform distribution of seeds in the gland, many practitioners use peripheral seed loading patterns to reduce urethral toxicity; and (3) As preoperative and intraoperative treatment planning is becoming standard, the apparent role of nomograms is diminished. The nomogram method is reviewed in terms of: (1) total activity predicted, (2) target coverage (as planned in the operating room and as calculated from postimplant computed tomography studies), and (3) reproducibility (i.e., patient-to-patient and planner-to-planner variability). In each case, the computer-optimization system for intraoperative planning currently in use at our institution was taken as the 'gold standard'. Methods and Materials: We compared for the same patient the results of nomogram planning to those yielded by genetic algorithm (GA) optimization in terms of total activity predicted (n=20 cases) and percent target coverage (n=5 cases). Furthermore, we examined retrospectively the dosimetry of 61 prostate implants planned with the GA (n=27) and the current implementation of Anderson nomograms (n=34). Results: Nomogram predictions of the total activity required are in good agreement (within 10%) with the GA-planned activity. However, computer-optimized plans consistently yield superior plans, as reflected in both pre- and postimplant analyses. We find also that user (specifically, treatment planner) implementation of the nomograms may be a major source of variability in nomogram planning - a difficulty to which robust computer optimization is less prone. Conclusions: Nomograms continue to

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

    Lanreotide (D-β-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

  15. Autoradiographic comparison of [125I]epidepride and [125I]NCQ 298 binding to human brain extrastriated dopamine receptors

    Extrastriatal D2-dopamine receptors can be visualized in the monkey and human brain using the benzamides [11C]- and [76Br]FLB 457 in PET and [123I]epidepride in SPECT but not with the salicylamide analogues [76Br]FLB 463 and [123I]NCQ 298. To clarify the background for the differences in binding seen in vivo, we have compared the in vitro binding of [125I]epidepride and [125I]NCQ 298, using human whole hemisphere autoradiography. The images obtained with any radioligand showed detailed distribution with very dense binding in the putamen and the caudate nucleus and with the same detailed extrastriatal distribution. Thus, the divergent results obtained in vivo cannot be explained by different binding properties of the extrastriatal receptors

  16. 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.

  17. 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)

  18. Design and synthesis of [(125)I]Pyricoxib: A novel (125)I-labeled cyclooxygenase-2 (COX-2) inhibitors.

    Tietz, Ole; Dzandzi, James; Bhardwaj, Atul; Valliant, John F; Wuest, Frank

    2016-03-15

    Cyclooxygenase-2 (COX-2) is the key enzyme in the prostaglandin synthesis pathway which is involved in various pathophysiological conditions. The enzyme is membrane bound and located inside of the endoplasmic reticulum and nuclear membrane. Effective perfusion of inhibitors to the active site requires lipophilic drugs, which consequently display high unspecific background accumulation, for example, in fatty tissues. The objective of this work was the development of a small molecule radiolabeled with a long-lived iodine radioisotope to enable longer imaging times and better target-to-background ratios. A group of iodinated compounds (8-10) was synthesized and identified as selective COX-2 inhibitors (COX-2 IC50=0.85-13 μM). Molecular docking results provided the theoretical support for the experimental COX-2 inhibition data. Furthermore, a novel (125)I-containing trifluoro-pyrimidine compound ([(125)I]Pyricoxib) was prepared via radioiododestannylation reaction as potent and selective COX-2 inhibitor. Radiosynthesis of [(125)I]Pyricoxib was accomplished with innovative fluorous chemistry using fluorous chloroamine-T (F-CAT) as novel oxidizing agent in high radiochemical yields of 91 ± 4%. PMID:26898334

  19. 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

  20. 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)

  1. 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

  2. Intercomparison of ionisation chamber measurements from {sup 125}I seeds

    Davies, J.B. [Australian Nuclear Science and Technology Organisation, New Illawarra Road, Building 23, Lucas Heights, NSW 2234 (Australia); Institute of Medical Physics, University of Sydney, NSW 2006 (Australia); E-mail: jbd@ansto.gov.au; Enari, K.F. [Cancer Care Centre, St George Hospital, Kogarah, NSW 2217 (Australia); Baldock, C. [Institute of Medical Physics, University of Sydney, NSW 2006 (Australia)

    2007-05-15

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

  3. 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.

  4. 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)

  5. 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

  6. Studies on characteristics of dosimetry for 125I ophthalmic applicator

    Isodose curves for 125I ophthalmic application in different geometry and activity can be obtained using the empirical formula based on suitable geometric model. The results of surface dose rate determined with lithium fluoride (LiF) thermoluminescent dosimeter (TLD's) chips in water-organic glass phantom and air had no obvious difference and the surface dose rate and its uniformity, (3.46 +- 0.011) and (0.178 +- 0.15) nGy/h·107Bq were obtained. Count measurements and dose determinations for the front and back etc. of the ophthalmic applicator with BaF2 scintillation detector and LiF TLD's had revealed the space distribution of dose for 125I ophthalmic applicator in which dose on the back was less than 0.1% of that on the front. The distribution of the absorbed dose rate along the eye axis had been measured using LiF TLD's in water-organic glass phantom. The measured and calculated dose data indicated that when measuring distances were larger than about 5 mm the experimental results agreed with those from calculation within the range of error, otherwise the measured values were lower, still it could be explained by experimental conditions

  7. 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

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

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

    2011-01-15

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

  9. 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)

  10. 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)

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

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

    1987-10-01

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

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

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

  13. Autoradiographic comparison of [125I]epidepride and [125I]NCQ 298 binding to human brain extrastriated dopamine receptors.

    Hall, H; Halldin, C; Jerning, E; Osterlund, M; Farde, L; Sedvall, G

    1997-07-01

    Extrastriatal D2-dopamine receptors can be visualised in the monkey and human brain using the benzamides [11C]- and [76Br]FLB 457 in PET and [123I]epidepride in SPECT but not with the salicylamide analogues [76Br]FLB 463 and [123I]NCQ 298. To clarify the background for the differences in binding seen in vivo, we have compared the in vitro binding of [125I]epidepride and [123I]NCQ 298, using human whole hemisphere autoradiography. The images obtained with any radioligand showed detailed distribution with very dense binding in the putamen and the caudate nucleus and with the same detailed extrastriatal distribution. Thus, the divergent results obtained in vivo cannot be explained by different binding properties of the extrastriatal receptors. PMID:9290072

  14. 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)

  15. 125I-TOC和125I-F-PGA放射化学纯度的测定%Determination of Radiochemical Purity of 125 I-TOC and 125 I-F-PGA

    杨科亚; 范我; 张友九; 许玉杰; 朱然; 胡明江

    2006-01-01

    为比较3种测定125I标记的奥曲肽(TOC)和叶酸-青霉素酰化酶复合物(F-PGA)的放射化学纯度(RCP)的方法是否具有一致性,采用Iodogen法对TOC和F-PGA进行放射性碘标记,并用高效液相色谱法(HPLC)、三氯醋酸(TCA)沉淀法和纸层析法测定标记物的放射化学纯度(RCP),其中TCA沉淀法设4种蛋白浓度以观察其对RCP测定的影响.结果表明,HPLC和纸层析法均能有效分离标记物和游离碘,且HPLC测定这种标记物的RCP最为精确可信.在TCA沉淀法中,用0.2%的小牛血清白蛋白(BSA)测得的RCP最低,而用其它3个BSA浓度测得的RCP则无明显差异(P>0.05);当RCP<10%时,TCA沉淀法与纸层析法测得的RCP间无明显差异(P>0.05),而要高于HPLC(P<0.01);当RCP>10%时,对125I-TOC而言,TCA沉淀法要略低于HPLC和纸层析(P<0.05),但后2种方法无明显差异(P>0.05),且对125I-F-PGA而言,3种方法无明显差异(P>0.05).3种方法两两之间显著相关(r=0.996~0.999,P<0.001).

  16. Optimization of sup 125 I ophthalmic plaque brachytherapy

    Astrahan, M.A.; Luxton, G.; Jozsef, G.; Liggett, P.E.; Petrovich, Z. (Univ. of Southern California School of Medicine, Los Angeles (USA))

    1990-11-01

    Episcleral plaques containing {sup 125}I sources are often used in the treatment of ocular melanoma. Within four years post-treatment, however, the majority of patients experience some visual loss due to radiation retinopathy. The high incidence of late complications suggests that careful treatment optimization may lead to improved outcome. The goal of optimization would be to reduce the magnitude of vision-limiting complications without compromising tumor control. We have developed a three-dimensional computer model for ophthalmic plaque therapy which permits us to explore the potential of various optimization strategies. One simple strategy which shows promise is to maximize the ratio of dose to the tumor apex (T) compared to dose to the macula (M). By modifying the parameters of source location, activity distribution, source orientation, and shielding we find that the calculated T:M ratio can be varied by a factor of 2 for a common plaque design and posterior tumor location. Margins and dose to the tumor volume remain essentially unchanged.

  17. Simulation of strand break induction by DNA incorporated 125I

    Monte Carlo calculation of 125I Auger cascades has provided electron spectra for individual decays with kinetic energies determined by Dirac-Fock methods. For these Auger electrons, track structures in liquid water have been generated and superimposed on a straight DNA plasmid model with atomic coordinates taken from X ray diffraction studies. Due to its high geometrical resolution, this DNA model makes it possible to localize the energy deposition or/and radical production events relative to the submolecular units of the DNA strands (base, sugar, phosphate). Furthermore, it is possible to distinguish between events inside (direct) and outside (indirect, radical production) of the atomic volumes of the DNA. On the basis of different assumptions for the effectiveness of strand break induction by direct hits and by OH· and H· radicals, the yields for single- and double strand breaks, as well as the strand break distribution as a function of the distance from the decay site, has been evaluated and compared with experimental and theoretical results from the literature

  18. 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)

  19. 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)

  20. 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

  1. 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.)

  2. 125I disk source using charcoal activated polyurethane foam rubber mat

    Uniform 125I disk sources were prepared as a reference source to calibrate NaI(Tl) scintillation detector to measure 125I activity on a filter of air monitor in a laboratory. The base of the disk source was a charcoal activated polyurethane foam rubber mat of 75 mm in diameter, 2 mm in thickness. 125I disk sources of approximate 0.5 kBq, 1 kBq, and 10 kBq were obtained through immersing disks in ethanol solution containing Na125I of 0.5 kBq/ml, 1 kBq/ml and 10 kBq/ml, respectively, and then drying up them. The uniformity of the distribution of 125I on the disk source was estimated by analyzing the autoradiograph of the disk source using an imaging analyzer. The radioactivity of 125I was distributed uniformly on the surface of the disk source within an uncertainty of about 10%. (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. 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

  5. Binding and degradation of [125I]human growth hormone in rat adipocytes

    Iodinated human growth hormone [( 125I]hGH) binds to both specific and nonspecific sites on the surface of adipocytes isolated from the epididymal fat of normal rats. When adipocytes were incubated at 37 C with 1 nM [125I]hGH, specific binding increased for 30-60 min and thereafter remained approximately constant as long as the hormone was present in the medium. About 90% of the 125I released was soluble in 5% trichloroacetic acid and was in the form of iodotyrosine. The rate of 125I release from specific binding sites decreased by a factor of 4 when the temperature was lowered from 37 to 17 C. Replacement of some of the sodium chloride in the buffer with 25 mM ammonium chloride had little or no effect on the amount on 125I that bound to cells when [125I]hGH was present in the medium, but completely blocked the release of 125I from cells transferred to hormone-free medium. Ammonium chloride also significantly reduced both the release of 125I from nonspecific binding sites and the amount of 125I recovered in trichloroacetic acid-soluble form. Cloroquine, leupeptin, or colchicine nearly doubled the specific binding of [125I]hGH after 180 min and markedly slowed the release of 125I when cells were transferred to hormone-free medium. All of these agents also significantly reduced the rate of release of 125I from nonspecific binding sites. Incubation of adipose tissue from hypophysectomized rats with ammonium chloride, leupeptin, or colchicine failed to alter the ability of GH to increase glucose oxidation, induce refractoriness, or promote lipolysis in the presence of theophylline

  6. Binding and degradation of (/sup 125/I)human growth hormone in rat adipocytes

    Gorin, E.; Grichting, G.; Goodman, H.M.

    1984-08-01

    Iodinated human growth hormone (( /sup 125/I)hGH) binds to both specific and nonspecific sites on the surface of adipocytes isolated from the epididymal fat of normal rats. When adipocytes were incubated at 37 C with 1 nM (/sup 125/I)hGH, specific binding increased for 30-60 min and thereafter remained approximately constant as long as the hormone was present in the medium. About 90% of the /sup 125/I released was soluble in 5% trichloroacetic acid and was in the form of iodotyrosine. The rate of /sup 125/I release from specific binding sites decreased by a factor of 4 when the temperature was lowered from 37 to 17 C. Replacement of some of the sodium chloride in the buffer with 25 mM ammonium chloride had little or no effect on the amount on /sup 125/I that bound to cells when (/sup 125/I)hGH was present in the medium, but completely blocked the release of /sup 125/I from cells transferred to hormone-free medium. Ammonium chloride also significantly reduced both the release of /sup 125/I from nonspecific binding sites and the amount of /sup 125/I recovered in trichloroacetic acid-soluble form. Cloroquine, leupeptin, or colchicine nearly doubled the specific binding of (/sup 125/I)hGH after 180 min and markedly slowed the release of /sup 125/I when cells were transferred to hormone-free medium. All of these agents also significantly reduced the rate of release of /sup 125/I from nonspecific binding sites. Incubation of adipose tissue from hypophysectomized rats with ammonium chloride, leupeptin, or colchicine failed to alter the ability of GH to increase glucose oxidation, induce refractoriness, or promote lipolysis in the presence of theophylline.

  7. Biodistribution of 125I labeled recombinant macrophage migration inhibitory factors in inflammatory model of mice

    To evaluate 125I labeled recombinant macrophage migration inhibitory factors (rMIF) for the scintigraphic imaging of inflammation, rMIF was labeled with 125I by Iodo- gen method. 125I-rMIF was isolated by Sephadex G25 column. The stability, immune specificity of 125I-rMIF and its biodistribution in inflammatory model of mice were studied. The labeling yield of 125I-rMIF was 96.5%. It was stable within 48 h at room temperature. The biodistribution results showed that the 125I-rMIF was metabolized by the liver, the radioactivity clearance mainly happened in the kidney and the speed of the blood clearance was rapid. After caudal vein iniection with 125I-rMIF, the ratio of radioactivity uptake between inflammatory limb (target) and contra lateral healthy limb (non target)(T/NT) were 1.42, 1.35, 2.18 and 2.05 at 0.5, 1, 6, 24 h respectively. 125I-rMIF had the capability of locating the inflammatory foci. The advance of it is more obviously at the late stage than that at the early stage. 125I-rMIF may be a potential agent for the diagnosis of concealed and subacute inflammatory disease. (authors)

  8. 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

  9. 125I brachytherapy in the palliation of painful bone metastases from lung cancer after failure or rejection of conventional treatments

    Gilani, Saba; Zhong, Zhihui; Zhang, Tao; Zhang, Fujun; Gao, Fei

    2016-01-01

    Purpose This study sought to assess the safety and effect of 125I seed implantation for palliation of painful bone metastases from lung cancer after failure or rejection of conventional treatments. Materials and Methods 89 patients with painful bone metastases secondary to lung cancer were consented and enrolled in this study from June 2013 to May 2015. All patients had failed or refused conventional treatments underwent percutaneous CT-guided 125I seed implantation. The Brief Pain Inventory (BPI) was used to measure pain intensity prior to treatment (T0), 2, 4, 6, 8 and 12 weeks (T2, T4, T6, T8 and T12) after treatment in a 24-hour period. Analgesic, quality of life (QOL) scores and complications were also recorded. Four patients were excluded as they were lost to follow-up or had incomplete data. Results 85 patients with 126 bone metastases from lung cancer were treated. There were significantly lower scores after treatment in the visual analog scale (VAS) and analgesic. The VAS scores for worst pain was 6.3±1.8 at T0. At T2, T4, T6, T8 and T12, the score in a 24-hour period decreased to 4.9±1.2 (Pmetastases from lung cancer after failure or rejection of conventional treatments. PMID:26919235

  10. 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...

  11. 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

  12. Evaluation of murine placental degradation and transfer of [125I]iodo-epidermal growth factor

    Since epidermal growth factor (EGF) has been postulated to play a role in embryonic and fetal growth, a study was undertaken to assess the placental degradation and transfer of maternally administered EGF. Approximately 5 ng of purified [125I]iodo-EGF were injected iv into day 10, day 13, or day 17 pregnant CD-1 mice; radioactivity in plasma, placentas, and conceptuses was measured up to 2 h after injection. The time course analysis revealed an initial rapid decline in total plasma radioactivity followed by an increase that was maximal by approximately 30 min. Gel filtration (G-15, G-50) chromatography of plasma revealed that by 5 min, radioactivity was associated with free 125I and with material much larger than EGF. No apparent degradation of [125I]iodo-EGF occurred after direct incubation with maternal plasma. Placental radioactivity had an initial phase of decay between 1 and 5 min followed by an increase that became maximal between 30 and 60 min. Extracts of placentas made with 4 M urea in 0.2 M Tris-HCl, pH 8.0, and taken 1-30 min after injection revealed radioactivity coeluting predominantly with [125I]iodo-EGF at 1 min but shifting to mostly free 125I by 30 min. Uptake of radioactivity by conceptuses was not evident until about 15 min, and only free 125I was detected in extracts; the same results were obtained when 5 micrograms unlabeled EGF were injected simultaneously with [125I]iodo-EGF. Incubation of placental mince with [125I]iodo-EGF yielded [125I]MIT as the apparent major radioactive degradation product. Formation of [125I]MIT in vitro was both time- and temperature-dependent. At 37 C, marked formation of [125I]MIT was observed; at 22 C, only a negligible amount was formed after incubation of mince with [125I]iodo-EGF for 60 min. Incubation of [125I]iodo-EGF with kidney mince yielded predominantly free 125I

  13. 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 μm. 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.)

  14. 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)

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

    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. 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. 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. 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. 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

  17. Postimplantation dosimetric analysis of permanent transperineal prostate implantation: improved dose distributions with an intraoperative computer-optimized conformal planning technique

    Purpose: To compare the target coverage and dose to normal tissues after I-125 transperineal permanent implantation (TPI) of the prostate in 90 patients treated with one of three different transperineal techniques. Methods and Materials: Detailed postimplant dosimetric evaluations of permanent I-125 implantation procedures were performed on 30 consecutive patients treated between 1995-1996 who underwent TPI using a preplanning CT-based technique, on 30 consecutive patients treated in 1997-1998 who underwent an ultrasound-guided approach with intraoperative determination of seed distribution based on an I-125 nomogram, and on 30 consecutive patients in 1998-1999 who underwent TPI with intraoperative computer-based 3-dimensional conformal optimization. For all three techniques, postimplant CT scans were obtained 4-6 hours after TPI. Dosimetric parameters included V100, V90, V150, D100, D90, D80, as well as maximal and average doses to the urethra and rectal wall. These parameter outcomes are reported as a percentage of the prescription dose. Results: The intraoperative 3D-optimized technique (I-3D) provided superior target coverage with the prescription dose for all dosimetric variables evaluated compared to the other treatment techniques. The median V100, V90, and D90 values for the I-3D technique were 96%, 98%, and 116%, respectively. In contrast, the V100, V90, and D90 values for the CT preplan and ultrasound manual optimization approaches were 86%, 89%, and 88%, respectively and 88%, 92%, and 94%, respectively (I-3D versus other techniques: p < 0.001). The superior target coverage with the I-3D technique was also associated with a higher cumulative implant activity required by the optimization program. A multivariate analysis determined that the treatment technique (I-3D versus other approaches) was an independent predictor of improved target coverage for each parameter analyzed (p < 0.001). In addition, higher cumulative implant activities and smaller prostate

  18. 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

  19. 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)

  20. 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 ...

  1. (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

  2. 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

  3. 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

  4. 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

  5. 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.)

  6. 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.)

  7. 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

  8. Effect of fentanyl on 125I-β-CIT uptake in mice brain

    Objective: To investigate the effect of fentanyl on 125I-2β-carbomethoxy-3β-(4-iodophenyl) tropane (125I-β-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-β-CIT. 2)Two groups of animals were killed at 2 h after injection of 125I-β-CIT. 3)One group of animals were killed at 1 h after injection of 125I-β-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-β-CIT was detected at the fentanyl doses ranging from 125 to 300 μg/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 μg/kg fentanyl and the control group; while at the doses from 12.5 to 100 μg/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 μg/kg groups; brain stem: except 62.5 μg/kg group) than that of the controls. 2)The uptakes of 125I-β-CIT in the striatum, frontal cortex, hippocampus, brain stem, cerebellum and whole brain in the groups injected with 125I-β-CIT 10 min after fentanyl treatment were higher than that in the groups injected with 125I-β-CIT 1 h after fentanyl treatment. 3)The binding of 125I-β-CIT in the striatum, frontal cortex, hippocampus, brain stem, cerebellum and whole brain in the groups killed at 1 h after injection of 125I-β-CIT was higher than that in the control group, but without significant difference. Conclusion: Fentanyl may have different effects on 125I-β-CIT at various time points and doses

  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. 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 ...

  11. 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)

  12. 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

  13. 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

  14. 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

  15. 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)

  16. Preparation and characterization of 125I-labelled proinsulin for radioimmunoassay (Preprint No. CT-62)

    Bovine proinsulin is iodinated with 125I. The labelled proinsulin was purified over sephadex. The preparation was characterized for stability and immunoreactivity. A radioimmunoassay was standardized using this labelled preparation. (author)

  17. In vitro cell-mediated immunity assay using 125I-iododeoxyuridine

    We investigated an in vitro cell-mediated immunity assay using incorporation of 125I-iododeoxyuridine as an indicator of lymphocyte responsiveness to mitogen stimulation. The system permits the use of whole-blood cultures in rats and dogs

  18. 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.)

  19. SU-E-J-166: Sensitivity of Clinically Relevant Dosimetric Parameters to Contouring Uncertainty During Post Implant Dosimetry of Prostate Permanent Seed Implants

    Mashouf, S [Sunnybrook Odette Cancer Centre, Toronto, ON (Canada); University of Toronto, Dept. of Radiation Oncology, Toronto, ON (Canada); Ravi, A; Morton, G; Song, W [Sunnybrook Odette Cancer Centre, Toronto, ON (Canada); University of Toronto, Dept. of Radiation Oncology, Toronto, ON (Canada); Sunnybrook Research Institute, Toronto, ON (Canada)

    2015-06-15

    Purpose: There is a strong evidence relating post-implant dosimetry for permanent seed prostate brachytherpy to local control rates. The delineation of the prostate on CT images, however, represents a challenge as it is difficult to confidently identify the prostate borders from soft tissue surrounding it. This study aims at quantifying the sensitivity of clinically relevant dosimetric parameters to prostate contouring uncertainty. Methods: The post-implant CT images and plans for a cohort of 43 patients, who have received I–125 permanent prostate seed implant in our centre, were exported to MIM Symphony LDR brachytherapy treatment planning system (MIM Software Inc., Cleveland, OH). The prostate contours in post-implant CT images were expanded/contracted uniformly for margins of ±1.00mm, ±2.00mm, ±3.00mm, ±4.00mm and ±5.00mm (±0.01mm). The values for V100 and D90 were extracted from Dose Volume Histograms for each contour and compared. Results: The mean value of V100 and D90 was obtained as 92.3±8.4% and 108.4±12.3% respectively (Rx=145Gy). V100 was reduced by −3.2±1.5%, −7.2±3.0%, −12.8±4.0%, −19.0±4.8%, − 25.5±5.4% for expanded contours of prostate with margins of +1mm, +2mm, +3mm, +4mm, and +5mm, respectively, while it was increased by 1.6±1.2%, 2.4±2.4%, 2.7±3.2%, 2.9±4.2%, 2.9±5.1% for the contracted contours. D90 was reduced by −6.9±3.5%, −14.5±6.1%, −23.8±7.1%, − 33.6±8.5%, −40.6±8.7% and increased by 4.1±2.6%, 6.1±5.0%, 7.2±5.7%, 8.1±7.3% and 8.1±7.3% for the same set of contours. Conclusion: Systematic expansion errors of more than 1mm may likely render a plan sub-optimal. Conversely contraction errors may Result in labeling a plan likely as optimal. The use of MRI images to contour the prostate should results in better delineation of prostate organ which increases the predictive value of post-op plans. Since observers tend to overestimate the prostate volume on CT, compared with MRI, the impact of the

  20. SU-E-J-166: Sensitivity of Clinically Relevant Dosimetric Parameters to Contouring Uncertainty During Post Implant Dosimetry of Prostate Permanent Seed Implants

    Purpose: There is a strong evidence relating post-implant dosimetry for permanent seed prostate brachytherpy to local control rates. The delineation of the prostate on CT images, however, represents a challenge as it is difficult to confidently identify the prostate borders from soft tissue surrounding it. This study aims at quantifying the sensitivity of clinically relevant dosimetric parameters to prostate contouring uncertainty. Methods: The post-implant CT images and plans for a cohort of 43 patients, who have received I–125 permanent prostate seed implant in our centre, were exported to MIM Symphony LDR brachytherapy treatment planning system (MIM Software Inc., Cleveland, OH). The prostate contours in post-implant CT images were expanded/contracted uniformly for margins of ±1.00mm, ±2.00mm, ±3.00mm, ±4.00mm and ±5.00mm (±0.01mm). The values for V100 and D90 were extracted from Dose Volume Histograms for each contour and compared. Results: The mean value of V100 and D90 was obtained as 92.3±8.4% and 108.4±12.3% respectively (Rx=145Gy). V100 was reduced by −3.2±1.5%, −7.2±3.0%, −12.8±4.0%, −19.0±4.8%, − 25.5±5.4% for expanded contours of prostate with margins of +1mm, +2mm, +3mm, +4mm, and +5mm, respectively, while it was increased by 1.6±1.2%, 2.4±2.4%, 2.7±3.2%, 2.9±4.2%, 2.9±5.1% for the contracted contours. D90 was reduced by −6.9±3.5%, −14.5±6.1%, −23.8±7.1%, − 33.6±8.5%, −40.6±8.7% and increased by 4.1±2.6%, 6.1±5.0%, 7.2±5.7%, 8.1±7.3% and 8.1±7.3% for the same set of contours. Conclusion: Systematic expansion errors of more than 1mm may likely render a plan sub-optimal. Conversely contraction errors may Result in labeling a plan likely as optimal. The use of MRI images to contour the prostate should results in better delineation of prostate organ which increases the predictive value of post-op plans. Since observers tend to overestimate the prostate volume on CT, compared with MRI, the impact of the

  1. (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

  2. Surface redistribution of 125I-insulin in cultured human lymphocytes

    1981-01-01

    The cultured human lymphocyte (IM-9) binds 125I-insulin by a receptor- mediated process; the receptor, in turn, is regulated by the ligand. In the present study we have examined quantitatively the morphologic events involved in 125I-insulin interaction with the surface of the lymphocyte. At 2 min of incubation of 15 degrees or 37 degrees C, the ligand localizes preferentially at the villous surface of the cell, whereas with longer periods of incubation, the ligand distributes indistinguishabl...

  3. Intracellular modification of 125I-labeled epidermal growth factor by normal human foreskin fibroblasts

    Intracellular processing of 125I-labeled epidermal growth factor (EGF) in normal human foreskin fibroblasts was examined after incubation with saturating concentrations of [125I]EGF. This report describes the column chromatographic separation of multiple processed forms of EGF generated by human foreskin fibroblasts and their structural characterization. More than 95% of the cell-bound [125I]EGF was converted into multiple forms, which were separated into four distinct peaks of radioactivity using columns of Bio-Gel P-150 equilibrated with 0.2% sodium dodecyl sulfate. These were designated peaks 1-4. Cellular generation of these four peaks was dependent on culture conditions. Differences in absolute and relative amounts of peaks 1-4 were observed as a function of time of incubation at 37 C. In addition, chromatographic profiles of cell-associated 125I varied in relation to cell density. The radioactivity in peak 1 comigrated with 125I-labeled native EGF on nondenaturing polyacrylamide gels (pH 9.5), whereas peaks 2 and 3 exhibited more rapid electrophoretic mobilities. Electrophoretic mobilities of the radioactivity in peaks 2 and 3 were indistinguishable from those of chemically prepared derivatives of [125I]EGF which were lacking either one or six amino acid residues from the carboxyterminus, respectively. The EGF receptor bound the radioactive material in peak 2 with an affinity equal to or greater than that of EGF; however, the radioactivity in peak 3 was bound to a much lesser extent. The radiolabel in both peaks 2 and 3 was greater than 95% precipitable by antiserum to native EGF. The labeled material in peak 4 was composed of [125I]monoiodotyrosine, 125I-, and an unidentified peptide. None of the radiolabeled compounds in peak 4 interacted with the EGF receptor or with antiserum to native EGF

  4. 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)

  5. 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

  6. 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)

  7. Tissue distribution and excretion of 125I-lidamycin in mice and rats

    You-Ping Liu; Quan-Sheng Li; Yu-Rong Huang; Chang-Xiao Liu

    2005-01-01

    AIM: To investigate the tissue distribution, urinary and fecal excretions of 125I-lidamycin (125I-C-1027) in mice and its biliary excretion in rats.METHODS: The total radioactivity assay (RA method) and the radioactivity assay after precipitation with 200 mL/L trichloroacetic acid (TCA-RA method) were used to dete-rmine the tissue distribution, and the urinary and fecal excretions of 125I-C-1027 in mice and its biliary excretion in rats.RESULTS: Tissue concentrations reached the peak at the fifth minute after administration of 125I-C-1027 to mice. The highest concentration was in kidney, and the lowest in brain at all test-time points. The organs of the concentrations of 125I-C-1027 from high to low were kidney, lung, liver, stomach, spleen, uterus, ovary, intestine, muscle, heart, testis, fat, and brain in mice. The accumulative excretionamounts of 0-24 h, and 0-96 h after administration of125I-C-1027 were 68.36 and 71.64% in urine, and 2.60 and 3.21% in feces of mice, respectively, and the accumulative excretion amount of 0-24 h was 3.57% in bile in rats.CONCLUSION: Our results reflect the characteristics of the tissue distribution, urinary and fecal excretions of 125IC-1027 in mice and the biliary excretion of 125I-C-1027and its metabolites in rats, and indicate that 125I-C-1027and its metabolites are mainly distributed in kidney, and excreted in urine.

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

    Meezan, E.; Elgavish, A.; Roden, L.; Wallace, R.W.

    1986-03-05

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

  9. 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

  10. 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)

  11. 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

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

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

  13. 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

  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 comparison of [{sup 125}I]epidepride and [{sup 125}I]NCQ 298 binding to human brain extrastriated dopamine receptors

    Hall, Haakan; Halldin, Christer; Jerning, Eva; Oesterlund, Marie; Farde, Lars; Sedvall, Goeran

    1997-07-01

    Extrastriatal D{sub 2}-dopamine receptors can be visualized in the monkey and human brain using the benzamides [{sup 11}C]- and [{sup 76}Br]FLB 457 in PET and [{sup 123}I]epidepride in SPECT but not with the salicylamide analogues [{sup 76}Br]FLB 463 and [{sup 123}I]NCQ 298. To clarify the background for the differences in binding seen in vivo, we have compared the in vitro binding of [{sup 125}I]epidepride and [{sup 125}I]NCQ 298, using human whole hemisphere autoradiography. The images obtained with any radioligand showed detailed distribution with very dense binding in the putamen and the caudate nucleus and with the same detailed extrastriatal distribution. Thus, the divergent results obtained in vivo cannot be explained by different binding properties of the extrastriatal receptors.

  16. 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)

  17. Targeted radiotherapy of multicell neuroblastoma spheroids with high specific activity [125I]meta-iodobenzylguanidine

    Purpose: Iodine-125 induces cell death by a mechanism similar to that of high linear energy transfer (high-LET) radiation. This study investigates the cytotoxicity of high-specific-activity [125I]meta-iodobenzylguanidine (125I-mIBG) in human SK-N-MC neuroblastoma cells grown as three-dimensional multicellular spheroids. Materials and Methods: Spheroids were incubated with high-specific-activity 125I-mIBG (6 mCi/μg, 1000 times that of the conventional specific activity used for autoradiography). Cytotoxicity was assessed by fluorescence viability markers and confocal microscopy for intact spheroids, fluorescence-activated cell sorting and clonogenic assay, and clonogenic assays for dispersed whole spheroids. Distribution of radioactive mIBG was determined by quantitative light-microscope autoradiography of spheroid cryostat sections. Dose estimation was based on temporal knowledge of the retained radioactivity inside spheroids, and of the radiolabel's emission characteristics. Findings were compared with those of spheroids treated under the same conditions with 131I-mIBG, cold mIBG, and free iodine-125. Results: 125I-mIBG exerted significant cell killing. Complete spheroids were eradicated when they were treated with 500 μCi of 125I-mIBG, while those treated with 500 μCi or 1000 μCi of 131I-mIBG were not. The observed difference in cytotoxicity between treatments with 125I- and 131I-mIBG could not be accounted for by the absorbed dose of spheroid alone. The peripheral, proliferating cell layer of the spheroids remained viable at the moderate radioactivity of 100 μCi for both isotopes. Cytotoxicity induced by 125I-mIBG was quantitatively comparable by the peripheral rim thickness to that of 131I-mIBG at the dose of 100 μCi. The peripheral rim thickness decreased most significantly in the first 17 hours after initial treatment. There was no statistical decrease in the rim thickness identified afterwards for the second, third, and fourth days of incubation

  18. 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

  19. Accumulation and metabolism of [125I] HIPDM in the rat pancreas

    Our previous studies have shown a high accumulaiton of [125I] N,N,N'- trimethyl-N'- (2-hydroxy-3-methyl-5-iodobenzyl)- 1,3-propanediamine (HIPDM) in the human pancreas. In this study, the pancreatic accumulation and metabolism of [125I]HIPDM were studied in rats to determine the factors influencing its uptake by this organ. In biodistribution studies, [125I]HIPDM showed a high uptake by the pancreas similar to that by the brain and lungs, both organs with a low tissue pH. TLC analysis of pancreatic homogenate after the injection of [125I]HIPDM showed that it was metabolically stable in this organ. Moreover, in the pancreatic homogenate, the bulk of the radioactivity was recovered from the microsomal fraction, and the radioactivity bound to microsomal particles showed release that was dependent on the Ca2+ or Mg2+ concentration in the incubation medium. These results suggest that the initial pancreatic uptake of [125I]HIPDM may be a function of blood flow and governed by the pH gradient hypothesis, while subsequent retention may occur secondary to ionic binding within the pancreas. (author)

  20. Monte Carlo dosimetry for 125I and 60Co in eye plaque therapy

    Monte Carlo calculations of radiation dosimetry using morse code are performed for 125I and 60Co point sources in a cylindrical head phantom that simulates the geometry of eye plaque therapy for choroidal melanoma. We obtain the dose variation in the eye at submillimeter intervals over distances as close as 1 mm and up to 2.5 cm from the source. The calculations for 125I are performed for the phantom media of water, protein, and a homogenized protein--water mixture simulating the composition of the eye. Relative dose functions for 125I for these phantom media are fitted to second-degree polynomials. Agreement is found with published results. The relative dose function for 60Co at eye position in the water head phantom is fitted to a third-degree polynomial and compared with that for 60Co at the center of a large water sphere. A boundary effect due to the head phantom--air interface on the dose distribution for 60Co is demonstrated. The dose falloff with distance is faster for the eye geometry compared with the bulk geometry. We also show that the relative dose distributions within the tumor are comparable for 125I and 60Co by comparing their relative dose functions. This result is consistent with the success of clinical trials of large melanoma treatments with 125I plaques

  1. Labeling and biodistribution of therapeutic radiopharmaceutical for brain cancer 125I-Nimotuzumab in normal mice

    Nimotuzumab is a monoclonal antibody which known giving contribution in anti proliferation, pro apoptosis and antiangionik effect on the therapy of brain cancer (glioma). The labeling of monoclonal antibody nimotuzumab with 125I which radiate auger electrons has been done with idogen method. The best result of radiochemical purity (97%) was shown in fraction 6 with the mol ratio of nimotuzumab towards potassium iodide and iodogen was 1 : 2 : 1200. Radiochemical purity was examined by paper chromatography with whatman paper no. 1 as the stationary phase and ethano!-butanol-ammonium hydroxide with a ratio of 3 : 2 : 1 as the mobile phase. Rf Values for 125I-nimotuzumab is 0.0, while Rf value of 125I .is 0.9. The biodistribution result on normal mice for 72 hours showed that 125I-nimotuzumab not only has a long half-life time but also has high accumulation in liver (1.97 + 1.18%), kidney (0.82 + 0.28%) and muscle (0.61+ 0.98%). The highest accumulation in brain on normal mice (0.128 + 0.06 %) occurred 24 hours after injection. Based on the therapeutic effects and organ accumulation on normal mice, 125I-nimotuzumab could be potentially used for brain cancer therapy. (author)

  2. /sup 125/I-spiperone: a novel ligand for D/sub 2/ dopamine receptors

    Gundlach, A.L.; Largent, B.L.; Synder, S.H.

    1984-11-05

    /sup 125/I-Spiperone binds with high affinity K/sub D/ 0.3 nM) to a single specific site (B/sub max/ 34 pmole/g wet weight) in homogenates of rat corpus striatum. Specific binding is about 40-60 percent of total binding and is displaced stereo-specifically by butaclamol and clopenthixol. Neuroleptic drugs of various classes are potent inhibitors of /sup 125/I-spiperone binding (/sub i/'s 1-10 nM). Selective dopamine antagonists such as sulpiride (K/sub i/ 50 nM) and dopamine agonists such as apomorphine (K/sub i/ 200 nM) are also potent inhibitors. The drugs specificity of /sup 125/I-spiperone binding correlates well with that of /sup 3/H-spiperone binding, providing good evidence that /sup 125/I-spiperone labels D/sub 2/ dopamine receptors in striatal membranes. /sup 125/I-Spiperone, with its high specific activity (2200 Ci/mmol) may prove to be a useful ligand in studies examining D/sub 2/ dopamine receptors in soluble preparations and by autoradiography. Furthermore iodinated spiperone may be useful in radioreceptor assays of neuroleptic drug levels and, in a /sup 123/I-labeled form for imaging of dopamine receptors, in vivo, using single photon tomography. 18 references, 4 figures, 1 table.

  3. 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)

  4. 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

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

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

  6. 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)

  7. 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

  8. 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

  9. Simulation of 125I induced DNA strand breaks in a CAP-DNA complex

    The E. coli catabolite gene activator protein (CAP)-DNA complex with 125I located at the position of the H5 atom of the cytosine near the centre was incorporated into the PARTRAC track structure code. DNA strand breaks due to irradiation were calculated by track structure and radical attack simulations: strand breaks due to neutralisation of the highly charged 125Te ion were derived from a semi-empirical distribution. According to the calculations, the neutralisation effect dominates the strand breakage frequency at 2 bases away from the 125I decay site on both strands. The first breakage distribution counted from a 32P labelled end on the strand with 125I agreed well with experimental data, but on the opposite strand, the calculated distribution is more concentrated around the decay site and its yield is about 20% larger than the measured data. (author)

  10. Nanodosimetry of 125I – Auger electrons – Experiment and modeling

    The experiment with 125I-Auger electrons, interacting with gaseous nitrogen with size equivalent to segment of DNA in mass per unit area scale, are described. The discrete ionization cluster-size distributions have been obtained. The shapes of which are definitely determined by the size of the interaction volumes. The volume sizes studied in the present work are comparable with a segment of DNA and of nucleosome. The experiments have been carried out with the set up, called Jet Counter, and are the first cluster-size distributions as yet measured for an Auger-electron emitter like 125I. The experimental results have been compared with those obtained by Monte Carlo simulation. The results for 125I have been compared with calculated cluster size distribution for 131I.

  11. 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

  12. 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.

  13. 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.)

  14. Development of thyroid monitoring system for the measurement of 125I

    Iodine-125 has gained wide acceptance in medical science for diagnosis and therapeutic applications. A considerable number of radiation workers of BARC and BRIT are involved in the production of 125I and preparation of radio immunoassay (RIA) kits to meet medical requirement of the country. A state of the art Thyroid Monitoring System incorporated with 51 mm diameter x 3 mm thick NaI(Tl) detector is developed for in-vivo monitoring of 125I in radiation workers handling this radioisotope. The developed system also has provision to accommodate variable body sizes (child to adult). This paper presents the different aspects of the system and its calibration using IAEA neck phantom for estimation of thyroidal content of 125I. (author)

  15. 99mTc-albumin can replace 125I-albumin to determine plasma volume repeatedly

    Bonfils, Peter K; Damgaard, Morten; Stokholm, Knud H;

    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...

  16. A novel 125I-labeled phenylpiperidine radiotracer for σ1 receptor imaging

    Objective: Development of radioligands with high affinity and selectivity for σ1 receptors provides sensitive molecular probes to the early diagnosis of central nervous system (CNS) diseases. Method: [125I]1-(4-iodobenzyl)-4-cyano-4-phenylpiperidine ([125I]Pp-CN-I) was designed and synthesized via an iododestannylation reaction. Its biological evaluations in vitro and in vivo were carried out. Results: The Ki values of Pp-CN-I for σ1 and σ2 receptors were 2.14±0.44nM and 1.71±0.65μM, respectively. The radio-chemical purity (RCP) of [125I]Pp-CN-I was higher than 99.9 % by HPLC analysis after purification. The biodistribution results in normal mice showed that [125I] Pp-CN-I exhibited high initial brain uptake and quick washout from blood. But the radioactivity accumulation was also washed out quickly from the brain. Administration of haloperidol 5 min prior to injection of [125I]Pp-CN-I significantly reduced the concentration of radioactivity in organs known to contain σ1 receptors. SPECT imaging in SD rat also demonstrated high initial brain uptake of the radiotracer and quick washout from the brain. The LC-MS results of Pp-CN-I and its metabolites in rat brain indicated that oxidation is the major metabolic pathway. Conclusion: [125I]Pp-CN-I possesses high affinity and selectivity to σ1 receptors and binds to σ1 receptors specifically in vivo. The fast metabolic degradation in brain limits its further applications in clinic. (authors)

  17. Binding and degradation of 125I-insulin by renal glomeruli and tubules isolated from rats

    Isolated rat renal glomeruli and tubules were shown to exhibit specific binding of 125I-insulin and enzymatic degradation of the hormone. Binding to both renal fractions reached a plateau by 1 h at 220C and increased linearly with increasing protein concentrations. Binding was inhibited in both preparations by insulin and its analogues in the order of relative potency: insulin > despentapeptide insulin > proinsulin, but insulin was ten times more potent in inhibiting 125I-insulin binding to glomeruli than that to tubules, indicating a different affinity of receptors for the hormone in the two renal fractions (about 17 versus 210 μg unlabelled insulin/1 inhibiting 50% of the 125I-insulin binding to glomeruli and tubules, respectively). Bound 125I-insulin dissociated at a faster rate from tubules than from glomeruli; this release was accelreated by unlabelled insulin in both renal fractions, but to a greater extent in glomeruli than in tubules. Two-thirds of the total bound material released from glomeruli was found to be intact insulin as measured by trichloroacetic acid precipitation, whereas only one-third of the material released from tubules was intact. No direct relationship beteen binding and degradation of 125I-insulin in these renal fractions could be demonstrated, however, because of the release of proteolytic enzymes into the incubation medium resulting in almost all degradation being extracellular. Although differing in their affinity for 125I-insulin the high affinity glomerular insulin receptor and the lower affinity tubular insulin receptor have characteristics similar to those of insulin receptors in insulin responsive tissues. (orig.)

  18. Effects of temperature and gamma radiation on the stability of 125I-19-iodocholesterol

    The effect of the temperature and the gamma radiations on the 125I-19-iodocholesterol synthesized in our laboratory, has been studied; the time of caducity (t90) have been fixed from the rate constants of decomposition (k-bar) (20,9; 32,1 y 144.10-3h-1) for different temperatures (35, 50 and 75oC), and the value of Go(-M) (1,52) by radiation of samples of 19-iodocholesterol-125I (0,94 mg/ml) with 60Co (0,177 Mrad/h). (author). 4 figs., 8 refs

  19. 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.

  20. 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

  1. Sequence-specific DNA double-strand breaks induced by triplex forming 125I labeled oligonucleotides.

    Panyutin, I G; Neumann, R D

    1994-01-01

    A triplex-forming oligonucleotide (TFO) complementary to the polypurine-polypyrimidine region of the nef gene of the Human Immunodeficiency Virus (HIV) was labeled with 125I at the C5 position of a single deoxycytosine residue. Labeled TFO was incubated with a plasmid containing a fragment of the nef gene. Decay of 125I was found to cause double-strand breaks (DSB) within the nef gene upon triplex formation in a sequence specific manner. No DSB were detected after incubation at ionic conditio...

  2. 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

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

    Objective: To investigate the feasibility of developing the esophageal irradiating esophageal stent by placing 125I seed into it, the safety of the irradiative stent esophageal in animal experiments. Methods: (1) Development of esophageal 125I seed irradiated stent: a plastic 'bullet chamber' was moulded which held only one 125I seed. Its distribution and the spot where it was stitched on outside the stents. Thus esophageal intraluminal irradiating stents were developed. (2) Animal experiment: 36 rabbits were randomly assigned to 4 groups according to different irradiated dosage, 9 rabbits in each group. Intraluminal irradiated stents each with two 125I seeds totaling 22.2 MBq (group A), 44.4 MBq (group B) and 66.6 MBq (group C) respectively were placed in the rabbits esophagus and stents without 125I seeds were placed in group D rabbits esophagus which as control group. Three rabbits of each group were killed at the 2th, 4th, or 8th week after insertion of the stents, followed by esophageal contrast exam and CT scan to observe displacement of stents and transposition of 125I seed. The damage and its degree of esophagus and the lung, bronchus and large vessels around it caused by intraluminal irradiated stents were observed macroscopically or under optical and electric microscope. Results: (1) Development of esophageal intraluminal irradiated stents: 125I seed could be stitched on outside the stents firmly. Experiments of filling and releasing seeds in vitro were feasible. Irradiated steats could be easily placed in rabbits esophagus. It was safe for no losing of radioactive source has been found after they have been placed in esophagus for a long-term. (2) Animal experiments: the esophageal wall near 125I seed thickened most distinctly in mental groups during the 8th week[ group A(4.2 ± 0.3)mm,group B(4.3 ± 0.3)mm, group C(4.5 ± 0.3)mm]. There was a significant difference between the experimental group and control group [(3.1 ± 0.1) mm (P0.05). Four weeks

  4. 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

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

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

    2013-02-15

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

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

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

  7. 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

  8. 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

  9. Studies on the influence on the excretory kinetics of 125I-Adipiodon

    The possibility of influencing distribution and elimination of 125I-Adipiodon (125I-iodipamide meglumine) by a preceding administration of Falignost (iomeglamic acid) as well as by dose-time variants of the mechanic intravenous application of contrast medium was tested in 55 anicteric and 2 icteric patients within clinically indicated cholegraphic examination with the aim of methodical optimization. For the detection of principal regularities comparative studies with 125I-Adipiodon and Falignost in rats as well as examinations of protein binding of 125I-Adipiodon in the plasm of rats and in the plasm and in mixed serum (application in vitro) of patients by gel filtration with Epidex B 2 coarse and batch operation on more than 1,200 samples were additionally carried out. For combined cholecystography with intravenous infusion of Adipiodon in immediate temporal connection with the administration of Falignost a reduced visibility of the biliary tract in the X-ray picture is not to be expected as the consequence of the mutual influence of the contrast media. For intact excretory function of liver and kidneys the combined cholecystography can be recommended. The effects of a dose increase, of protracted infusion of Adipiodon and of the intravenous administration of 0.01 g metroclopramide on the demonstration of the biliary tract in the intravenous cholegram are outlined. (author)

  10. Studies on the influence on the excretory kinetics of /sup 125/I-Adipiodon

    Koenig, H. (Martin-Luther-Universitaet Halle-Wittenberg, Halle (German Democratic Republic). Radiologische Klinik)

    1982-07-01

    The possibility of influencing distribution and elimination of /sup 125/I-Adipiodon (/sup 125/I-iodipamide meglumine) by a preceding administration of Falignost (iomeglamic acid) as well as by dose-time variants of the mechanic intravenous application of contrast medium was tested in 55 anicteric and 2 icteric patients within clinically indicated cholegraphic examination with the aim of methodical optimization. For the detection of principal regularities comparative studies with /sup 125/I-Adipiodon and Falignost in rats as well as examinations of protein binding of /sup 125/I-Adipiodon in the plasma of rats and in the plasma and in mixed serum (application in vitro) of patients by gel filtration with Epidex B 2 coarse and batch operation on more than 1,200 samples were additionally carried out. For combined cholecystography with intravenous infusion of Adipiodon in immediate temporal connection with the administration of Falignost a reduced visibility of the biliary tract in the X-ray picture is not to be expected as the consequence of the mutual influence of the contrast media. For intact excretory function of liver and kidneys the combined cholecystography can be recommended. The effects of a dose increase, of protracted infusion of Adipiodon and of the intravenous administration of 0.01 g metroclopramide on the demonstration of the biliary tract in the intravenous cholegram are outlined.

  11. Binding of 125I-human growth hormone to specific receptors in human cultured lymphocytes

    The interaction of human growth hormone with human lymphocytes from an established culture (IM-9) was studied using 125I- human growth hormone. The binding of 125I-human growth hormone was rapid; with human growth hormone at 0.1 nM a steady state was observed in 90 min at 300. Bound labeled human growth hormone was dissociated rapidly by addition of excess unlabeled human growth hormone. Binding of 125I-human growth hormone to cultured lymphocytes was relatively insensitive to alterations in the pH and in the concentrations of Ca2+, Mg2+, EDTA. At 800 there was very little degradation of labeled human growth hormone or of the specific receptor sites. Tryptic digestion destroyed the capacity of cells to bind human growth hormone. The IM-9 cells bound all human growth hormone preparations but not unrelated hormones or nonprimate growth hormones. The binding of 125I-human growth hormone was inhibited 10 to 14 percent with 1 to 2 ng per ml of unlabeled human growth hormone and 50 percent with 30 to 40 ng per ml, well within the range of hormone concentrations in vivo. Analysis of steady state data revealed a single order of binding sites with an affinity constant of 1.3 x 109 M-1 and about 4000 binding sites per cell. Numerous human growth hormone preparations were assayed by use of this receptor system as well as by immunoassay and by bioassay in vivo. The po

  12. Labelling of human gastric inhibitory polypeptide with 125I using conjunction method

    Human gastric inhibitory polypeptide (GIP) was labelled with the conjunction method. The results showed that the conjunction method succeeds in protecting the immunoactivity of human GIP. The 125I-GIP was able to combine with its GIP antibody specifically. The binding rate was 50% at an antiserum dilution of 1.3 x 104

  13. A dot assay for the erythropoietin receptor using human recombinant sup 125 I-erythropoietin

    Vannucchi, A.M.; Grossi, A.; Rafanelli, D.; Vannucchi, L.; Ferrini, P.R. (Univ. and USL 10/D, Florence (Italy))

    1989-10-01

    A dot assay was developed for the detection of membrane receptor(s) for erythropoietin (Ep). A relatively homogeneous population of cells bearing the receptor for Ep was generated in the spleen of mice made anemic with phenylhydrazine and crude membrane extracts were prepared from spleen cell suspensions. Aliquots of the membrane extracts were applied to microdishes of nitrocellulose in a volume of 4 microliters. After free reactive sites were blocked, the microdishes were incubated for 2 h at 37 degrees C with {sup 125}I-labeled human recombinant Ep ({sup 125}I-rEp), and nitrocellulose bound radioactivity was determined thereafter. Reproducible curves were obtained, and a significant correlation between bound radioactivity and the amount of membrane proteins applied to the nitrocellulose dishes was found. Specific binding was saturable, reaching a plateau at 2.5 nM. Binding parameters of nitrocellulose-immobilized receptor were not significantly different from the values calculated using intact cells. No appreciable binding of {sup 125}I-rEp to control membranes at low Ep-receptor content was observed. Among a panel of growth factors, only unlabeled rEp was able to compete for the binding of {sup 125}I-rEp to nitrocellulose-immobilized membrane proteins in a dose-dependent fashion. The technique described herein may be of use in the study of the Ep receptor and as an assay for its purification. Moreover, it may also be of general application in the study of receptor-ligand interactions.

  14. 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

  15. 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)

  16. Differential elimination of radioiodine from single- and double-stranded 125I-DNA

    [125I]Iododeoxyuridyl residues in heat-denatured I-DNA underwent deiodination in solutions of sodium bisulfite. In 0.5 M bisulfite containing 1 M trimethylamine, 92% of the iodine was released from denatured DNA in 2.5 min at 60oC. By contrast iodine in native I-DNA remained stably bound under the same condition. The deiodination of [125I]I-deoxyuridine residues incorporated by enzymatic copying of oligomers 60 nucleotides in length was found to be pairing dependent. While 125I in iododeoxyuridine paired to deoxyadenosine in a complementary oligomer remained ≅ 90% covalently bound in the presence of 1 M bisulfate at 60oC, when the iodouridylate residue wa mismatched > 96% was eliminated in 4 min. The presence of mismatches in the two nucleotides adjacent to a [125I]iododeoxyuridine/deoxyadenosine pair increased the elimination of iodine. The results indicate that the deiodination reaction might be applied for the rapid detection of variations in natural DNA sequences. (author)

  17. 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.

  18. 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

  19. 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)

  20. Distribution of /sup 125/I-thyroxine in different organs and tissues of dietically obese rats

    Hartmann, K.; Voss, C.; Huebner, G. (Ernst-Moritz-Arndt-Universitaet, Greifswald (German Democratic Republic)); Weber, A. (Ernst-Moritz-Arndt-Universitaet, Greifswald (German Democratic Republic). Radiologische Klinik)

    1985-04-01

    The distribution of /sup 125/I-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 /sup 125/I-T/sub 4/ 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 /sup 125/I-T/sub 4/ distribution were found in the /sup 125/I-T/sub 4/ between HFD and LFD rats with relatively equal body weight and body composition. The reduced T/sub 4/ 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.

  1. 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)

  2. 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.)

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

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

  4. 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.

  5. 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

  6. Preparation of 125I labelled nerve growth factor and study of its pharmacokinetics

    125I-Nerve growth factor (125I-NGF) with more than 95% of radiochemical purity is prepared by chloramine-T method. After I.V. and I.M. injection of 125I-NGF, pharmacokinetics of NGF in mice is determined by SDS-PAGE method. The results show that concentration-time curves after I.V. injection are fitted to a 2-compartment model are those after I.M. injection are fitted to a 1-compartment model. After I.V. injection of 25 μg/kg, the elimination half life (t1/2(β)) is 3.65 h. After I.M. injection of 75, 25, 10, 3.3 μg/kg, t1/2(β) is 1.79, 2.25, 2.30, 3.24 h, respectively. The mean plasma clearance (CLs) is 0.37 L/(h·kg), the appearance volume of distribution (Vd) is 1.18 L/kg and the mean residence time (tr-bar) in mice is 2.78 h. The pharmacokinetics of 125I-NGF in mice is useful for clinical trial

  7. Labeling of polyamidoamine with 125I and its biodistribution in mice

    Objective: To investigate the biodistribution of 125I labeled dendrimer nanomaterial--polyamidoamine (PAMAM) in mice. Methods: Tyrosine was conjugated to four generation PAMAM by N-Hydroxysuccinimide,then 125I was labeled on PAMAM with chloramines-T method,and purified by dialysis. Labeling rate,radiochemical purity and stability of 125I-PAMAM were detected by radioactive thin layer chromatography scanning. The gamma imaging and biodistribution were detected by in vivo imaging system and gamma counter at one, four, eight, twenty-four and forty-eight hours after intravenous injection. Results: The 1H nuclear magnetic resonance results showed that about two tyrosines were conjugated to PAMAM. The 125I labeling rate was about 56% and radiochemical purity was more than 98%. The radiochemical purity of labeled compound remained more than 90% at 72 hours in vitro. In vivo imaging results showed that PAMAM was mainly accumulated in liver periphery. The gamma counter results showed that PAMAM mainly accumulated in liver, kidney and spleen, the excretion of PAMAM was slow and there has high dose of PAMAM in mice at 48 hours. Conclusion: PAMAM with no chemical modification was mainly accumulated in liver, kidney and spleen, and the excretion of PAMAM was slow, so PAMAM is not fit as drug carrier. PAMAM need to chemical modification to accelerate excretion and prevent the emergence of toxicity caused by accumulation in body. (authors)

  8. 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

  9. 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

  10. Retention and degradation of 125I-insulin by perfused livers from diabetic rats.

    Terris, S; Steiner, D F

    1976-04-01

    The retention of degradation of insulin by isolated perfused liver have been examined. Noncyclically perfused livers from streptozotocin-diabetic rats retained 25% and degraded 10% of 125I-insulin administered as a 1-min pulse. On gel filtration (Sephadex G50F), the degradation products released into the vascular effluent eluted in the salt peak. During the 45-min interval after the end of the 125I-insulin infusion, 0.19% of the total dose was excreted in the bile. 60-90% of this material consisted of iodinated, low-molecular-weight degradation products. Inclusion of native insulin with the 125I-insulin in the pulse depressed both the retention and degradation of iodinated material; however, this reflected increased retention and degradation of the total insulin dose (125I-insulin plus native hormone). The log of the total amounts of insulin retained and degraded were linearly related to the log of the total amount of insulin infused at concentrations between 12.7 nM and 2.84 muM. Increasing the amount of native insulin in the infused pulse also depressed the total amount of iodinated material found in the bile and led to the appearance in the bile of intermediate-sized degradation products that did not simultaneously appear in the vascular effluent. Addition of high concentrations of glucagon to the infused 125I-insulin had no effect on the retention or degradation of the labeled hormone, or on the apparent size and amount of iodinated degradation products found in the vascular effluent or in the bile. Preinfusion of concanavalin A inhibited both 125I-insulin retention and degradation. A greater depression by concanavalin A of degradation than binding was also observed with isolated hepatocytes. In contrast to 125I-insulin, the retention and degradation of two iodinated insulin analogues of relative low biological potency, proinsulin and desalanyl-desasparaginyl insulin, were small. The amount of radioactivity appearing in the bile after infusion of these

  11. [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.)

  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. 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

  14. Cytotoxic effects of 125I-labeled PBZr ligand PK 11195 in prostatic tumor cells: therapeutic implications

    The effect of [125I]PK 11195 was examined in human prostatic tumor cells (DU 145) in culture and compared with Na[125I] and non-radioactive PK 11195. [125I]PK 11195 was clearly cytocidal. The data for dose-related cell survival with [125I]PK 11195 showed a linear relationship. Na[125I] or non-labeled PK 11195 at similar concentrations did not lead to any cell killing. The uptake of [125I]PK 11195 and [3H]PK 11195 in cells was very similar. Fragmentation of DNA measured by agarose gel electrophoresis showed that exposure of DU 145 cells to [125I]PK 11195 for 1, 4 or 24 h caused no fragmentation. These results indicate that nuclear DNA is not the prime binding site for [125I]PK 11195, which is consistent with the presence of specific peripheral benzodiazepine receptors (PBZr) in the mitochondria. The cell killing effect of [125I]PK 11195 suggests the use of PBZr ligand for radiotherapy

  15. 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

  16. Human growth hormone radioiodination using different batches of 125I of various ages

    The reproducibility and the influence of the batch and decay level of Na125I on the radioiodination of human growth hormone (hGH) were examined by a polyacrylamide gel electrophoresis (PAGE) technique. The between-day coefficient of variation (CV) exhibited a value of 11.9% for labelling yields and 14.3% for antibody specific binding. The within-day variation for different shipments and isotope decay-levels was similar to that for the control experiment, carried out under the same conditions, using Na125I from a single lot. The results indicate that the decay-level and batch do not significantly influence either the yields or the immunological properties of the labelled product. The suitability of this PAGE technique as a control test for radioiodinated proteins is established by comparison with gel chromatography on Sephadex G-100. (Auth.)

  17. 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)

  18. 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)

  19. Preparation of [123I]- and [125I]epidepride: a dopamine D-2 receptor antagonist radioligand

    (S)-(-)-N-[(1-ethyl-2-pyrrolidinyl)methyl]-5-[123I] iodo-2,3-dimethoxybenzamide (TDP 517) (proposed generic name, [123I]epidepride) is the iodine-123 substituted analogue of isoremoxipride (FLB 457), both of which are very potent dopamine D-2 antagonists (epidepride KD 0.024 nM). [123I] Epidepride was radioiodinated in 60-70% radiochemical yields in 35 min from the corresponding 5-(tributyltin) derivative using Na123I with a specific radioactivity of 3000 Ci/mmol, and oxidized in situ with chloramine-T. The aryltin precursor was prepared from non-labelled epidepride by palladium-catalyzed stannylation using bis(tri-n-butyltin) in triethylamine. Alternatively, using no carrier-added Na125I as the radioisotope, [125I] epidepride at 2000 Ci/mmol specific radioactivity was prepared in 86% radiochemical yield and 99% radiochemical purity after purification by reverse phase HPLC in ethanolic phosphate buffer. (author)

  20. 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

  1. 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

  2. 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

  3. 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.)

  4. 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.)

  5. 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

  6. 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

  7. 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, ...

  8. 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

  9. Measurement of specific radioactivity of 125I, 139Ce, etc 7 kinds of nuclide solution

    The decay characteristic of 125I, 139Ce, 88Y, 57Co, 60Co, 137Cs and 134Cs radio-nuclide and the principle for measurement of specific activity of the seven kinds of nuclide with coincidence method, 4πγ ionization room method, spectroscopy method and summing peak method are simply is described. The results compare with the measurement result from National Institute of Metrology P.R. China, they are agreeable within uncertainty. (authors)

  10. 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

  11. 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)

  12. 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)

  13. 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)

  14. Autoradiographic localization of substance P receptors using 125I substance P

    This paper describes a method for localization of substance P receptors in the rat central nervous system using 125I labeled substance P in an autoradiographic procedure. Particularly high densities of substance P receptors were observed in the olfactory bulb, dentate gyrus, amygdala, superior colliculus, and locus coeruleus. Surprisingly low densities of substance P receptors were found in the substantia nigra pars reticulata, a region which contains high concentrations of substance P

  15. 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.)

  16. Brachytherapy of ocular melanoma : physical and dosimetric aspects of 125I ophthalmic plaques

    Off-axis absorbed dose distribution of ophthalmic plaques is a useful parameter for the explanation of some observed biological effects. From a specific dosimetric software, developed in our brachytherapy department, and from our measurements around 125I eye plaque, we studied the dose distribution effects on the spread of activities inside the plaques. After analysis of experimental data, we observed also that the dose distribution in the penumbra area may be described easily with decrement lines. (author). 17 refs., 9 figs

  17. 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 μg 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

  18. 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.

  19. 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

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

    Angelo, Kamilla; Korolkova, Yuliya V; Grunnet, Morten;

    2003-01-01

    The wild-type scorpion toxin BeKm-1, which selectively blocks human ether-a-go-go related (hERG) channels, was radiolabeled with iodine at tyrosine 11. Both the mono- and di-iodinated derivatives were found to be biologically active. In electrophysiological patch-clamp recordings mono-[127I]-BeKm-1...... 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...... [125I]-BeKm-1 to the hERG channel to an IC50 of 7 nM. In autoradiographic studies on rat hearts, binding of [125I]-BeKm-1 was dose-dependent and could partially be displaced by the addition of excess amounts of non-radioactive BeKm-1. The density of the radioactive signal was equally distributed in the...

  1. 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)

  2. Pharmacokinetics of 125-I-labelled meta-iodo-benzyl-guanidine : Preliminary results

    The study of some pharmacokinetics providing the mechanism of uptake amd metabolism parameters for the 125-I-mIBG is described. NMRI mice are used for plasma binding study, the animals are killed by decapitation after intravenously (IV) injection of 125-I-mIBG. Wistar rats are used in urinary excretion study. After IV injection, animals are placed in metabolic cages to collect urine. For biodistribution, the rats are killed at different time intervals. The considered organs are removed. The radioactivity of all parameters was performed by gamma counter. The results show that the blood clearance is very high after several hours post injection and very high after 72 hours. Furthermore, we note a rapid excretion of radioactivity 24 hours post injection. However, we observe that 72 hours after injection, the radioactivity per gram of different organs was normalized according to the adrenal glands. Also, we note, that the adrenal glands may be the only target organs 48 hours post injection. These results confirm that 125-I-mIBG a high affinity for the adrenergic innervation organs (Adrenal glands, salivary glands, heart and spleen)

  3. 10-year biochemical (prostate-specific antigen) control of prostate cancer with 125I brachytherapy

    Purpose: To report 10-year biochemical (prostate-specific antigen [PSA]) outcomes for patients treated with 125I brachytherapy as monotherapy for early-stage prostate cancer. Methods and Materials: One hundred and twenty-five consecutively treated patients, with clinical Stage T1-T2b prostate cancer were treated with 125I brachytherapy as monotherapy, and followed with PSA determinations. Kaplan-Meier estimates of PSA progression-free survival (PFS), on the basis of a two consecutive elevations of PSA, were calculated. Aggregate PSA response by time interval was assessed. Comparisons were made to an earlier-treated cohort. Results: The overall PSA PFS rate achieved at 10 years was 87% for low-risk patients (PSA125I achieves a high rate (87%) of biochemical and clinical control in patients with low-risk disease at 10 years. The decline of PSA following brachytherapy with low-dose-rate isotopes can be protracted. Absolute PSA and PFS curves merge, and are comparable at 10 years

  4. 125I brachytherapy combined with chemotherapy of advanced non-small cell lung cancer

    林元强; 孙昱; 王任婕; 高识; 陈滨; 孙步彤; 马庆杰; 纪铁凤; 张海山

    2015-01-01

    This study was to evaluate effect of 125I brachytherapy combined with chemotherapy on advanced non-small cell lung cancer (NSCLC). Patients with NSCLC in stages III to IV were divided into two groups: Group A (n = 27) received 125I brachytherapy combined with gemcitabine and cisplatin (GP) chemotherapy, and Group B (n = 27) received GP chemotherapy only. The results showed that the overall response rate and median progression-free survival time were 78%and 11.5 months in Group A, 41%and 8 months in Group B, respectively (P 0.05). The interventional complications in Group A included 5 patients with postoperative pneumothorax and 4 patients with hemoptysis. No patients had radiation pneumonia, radiation esophagitis or esophagotracheal fistula. Chemotherapy treatment-related toxicities were not significantly different between the two groups. The relief of tumor-associated symptoms including cough, hemoptysis, chest pain, and short breath was found in both groups, without statistical difference in remission rates between Groups A and B (P >0.05). In conclusion, 125I brachytherapy combined with chemotherapy proved to be safe and effective for treating advanced NSCLC with few complications. It improves local control rate and prolongs the progression-free survival time.

  5. 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

  6. Characterization of pancreatic somatostatin binding sites with a 125I-somatostatin 28 analog

    Somatostatin binding to guinea pig pancreatic acinar cell plasma membranes was characterized with an iodinated stable analog of somatostatin 28 (S28): 125I-[Leu8,DTrp22,Tyr25]S28. The binding was highly dependent on calcium ions. In 0.2 mM free Ca2+ medium, binding at 37 degrees C was saturable, slowly reversible and exhibited a single class of high affinity binding sites (KD = 0.05 +/- 0.01 nM, Bmax = 157 +/- 33 fmol/mg protein). Dissociation of bound radioactivity occurred with biphasic kinetics. Rate of dissociation increased when dissociation was measured at a time before equilibrium binding was reached. In 30 nM free Ca2+ medium, binding affinity and maximal binding capacity were decreased by about 4-fold. Decreasing calcium concentrations increased the amount of rapidly dissociating form of the receptor. Somatostatin 14 antagonist, Des AA1,2[AzaAla4-5,DTrp8, Phe12-13]-somatostatin was active at the membrane level in inhibiting the binding. We conclude that using 125I-[Leu8,DTrp22,Tyr25]S28 as radioligand allows us to characterize a population of specific somatostatin receptors which are not different from those we previously described with the radioligand 125I-[Tyr11]-somatostatin. Somatostatin receptors could exist in two interconvertible forms. Calcium ions are an essential component in the regulation of the conformational change of somatostatin receptors

  7. Backscatter measurements from a single seed of 125I for ophthalmic plaque dosimetry

    To determine the dosimetric effect of a gold plaque applicator used in 125I ophthalmic irradiation, relative dose rates at points 2--18 mm transverse to the axis of a single seed of 125I were measured in an acrylic phantom under three different measurement conditions. The detectors were 1-mm diameter x 3-mm length LiF thermoluminescent dosimeters (TLD's). Conditions corresponded to the following: (i) full scatter, (ii) the presence of an ophthalmic gold plaque, and (iii) no scatter material on the side of the seed opposite to the TLD's. The dose rate with the gold plaque is less than that with full scatter phantom. There is no significant decrease in dose rate at 2.2 mm from the seed. Dose rate is significantly reduced at greater distances. The does rate decrease ranges from 4% at 5 mm to 10% at 18 mm. The 125I seed in the gold plaque gives 3%--5% higher dose rate than in the absence of backscatter material

  8. 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

  9. Evaluation of two (125)I-radiolabeled acridine derivatives for Auger-electron radionuclide therapy of melanoma.

    Gardette, Maryline; Viallard, Claire; Paillas, Salomé; Guerquin-Kern, Jean-Luc; Papon, Janine; Moins, Nicole; Labarre, Pierre; Desbois, Nicolas; Wong-Wah-Chung, Pascal; Palle, Sabine; Wu, Ting-Di; Pouget, Jean-Pierre; Miot-Noirault, Elisabeth; Chezal, Jean-Michel; Degoul, Francoise

    2014-08-01

    We previously selected two melanin-targeting radioligands [(125)I]ICF01035 and [(125)I]ICF01040 for melanoma-targeted (125)I radionuclide therapy according to their pharmacological profile in mice bearing B16F0 tumors. Here we demonstrate in vitro that these compounds present different radiotoxicities in relation to melanin and acidic vesicle contents in B16F0, B16F0 PTU and A375 cell lines. ICF01035 is effectively observed in nuclei of achromic (A375) melanoma or in melanosomes of melanized melanoma (B16F0), while ICF01040 stays in cytoplasmic vesicles in both cells. [(125)I]ICF01035 induced a similar survival fraction (A50) in all cell lines and led to a significant decrease in S-phase cells in amelanotic cell lines. [(125)I]ICF01040 induced a higher A50 in B16 cell lines compared to [(125)I]ICF01035 ones. [(125)I]ICF01040 induced a G2/M blockade in both A375 and B16F0 PTU, associated with its presence in cytoplasmic acidic vesicles. These results suggest that the radiotoxicity of [(125)I]ICF01035 and [(125)I]ICF01040 are not exclusively reliant on DNA alterations compatible with γ rays but likely result from local dose deposition (Auger electrons) leading to toxic compound leaks from acidic vesicles. In vivo, [(125)I]ICF01035 significantly reduced the number of B16F0 lung colonies, enabling a significant increase in survival of the treated mice. Targeting melanosomes or acidic vesicles is thus an option for future melanoma therapy. PMID:24691673

  10. 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

  11. 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

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

    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

  13. 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)

  14. 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

  15. Bioactivity assays and application of 125I labeled human mouse chimeric anti-CD22 monoclonal antibody SM03

    To investigate the bioactivity and application of 125I labeled human mouse chimeric monoclonal SM03, SM03 was labeled with 125I using Indogen method. The labeled mixture was purified by Sephacryl S-300 HR separation chromospectry. The purity and concentration of separated fractions were determined by HPLC and Protein Assay Kit, respectively. Competitive binding method and ELISA method were used for bioactivity assays. 125I-SM03 was applied to screen cell lines which express the most abundant CD22 antigen. The purity and recovery of 125I-SM03 were >99% and >47%, respectively. The bioactivity of 125I- SM03 and SM03 hasn't significant difference in statistics. Ramos cell line had the strongest special radioactivity when 125I-SM03 bound with in Raji, Daudi and Ramos cell lines. Indogen method is a good way to label Human mouse chimeric anti-CD22 monoclonal antibody SM03 and the label will not affect the activity of SM03. The 125I-SM03 not only can be used for detect agent, but also may be put into market for NHL therapy. (authors)

  16. 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.)

  17. Radiofrequency ablation and percutaneous permanent iodine-125 implantation as salvage therapy for giant recurrent sclerosing epithelioid fibrosarcoma of the chest wall: A case report

    KE, SHAN; DING, XUE-MEI; GAO, JUN; WANG, SHAO-HONG; ZHANG, JUN; KONG, JIAN; SUN, WEN-BING

    2015-01-01

    Sclerosing epithelioid fibrosarcoma (SEF) is a rare soft-tissue sarcoma for which there is no standardized treatment regimen available. The current treatment options for SEF are resection, radiation and chemotherapy. Surgical resection remains the mainstay of therapy for SEF. However, SEF is an aggressive tumor that is prone to repeated local recurrence if not widely excised. Radiation and chemotherapy are less commonly used due to the insensitivity of SEF to these therapies. The treatment of recurrent SEF is even more challenging. The present study describes a patient who presented with a giant recurrent SEF arising from the chest wall that was accompanied by emergent bleeding. The patient was a 70-year-old male who had multiple comorbid diseases, including hypertension and chronic cardiac dysfunction. A computed tomography (CT) scan indicated the involvement of the sternum and anterior mediastinum. However, the patient refused any further surgery. Subsequent to careful discussion and consideration, radiofrequency (RF) ablation and percutaneous iodine-125 implantation was administered. The emergent bleeding was successfully stopped and the tumor was eliminated using RF ablation. Percutaneous iodine-125 implantation under CT guidance established effective control on the growth of the tumor involving the mediastinum. Despite this, the tumor recurred 6 months after treatment. The patient refused any further treatment and was discharged. In conclusion, RF ablation and percutaneous permanent iodine-125 implantation is a feasible and safe salvage therapy for patients with recurrent SEF of the chest wall. PMID:26137032

  18. 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

  19. 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

  20. 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.

  1. 50th Anniversary of the first successful permanent pacemaker implantation in the United States: historical review and future directions.

    Beck, Hiroko; Boden, William E; Patibandla, Sushmitha; Kireyev, Dmitriy; Gutpa, Vipul; Campagna, Franklin; Cain, Michael E; Marine, Joseph E

    2010-09-15

    June 2010 marks the 50th anniversary of the first successful human cardiac pacemaker implantation in the United States. On June 6, 1960, in Buffalo, New York, Dr. William Chardack implanted a pacemaker, designed and built by Wilson Greatbatch, an electrical engineer and inventor, in a 77-year old man with complete atrioventricular block, extending the patient's life by 18 months. This landmark event ushered in a new era of implantable cardiac pacemakers with batteries and leads of high reliability and increasing durability. Over the past half century, the field of electrophysiology and implantable devices for the management of cardiac conduction disturbances has evolved dramatically. Today's pacemakers include increasingly complex features such as telemetry monitoring, auto programmability, and hemodynamic sensors. New-generation leads present a sophisticated design with improved geometry and steroid-eluting tips to reduce chronic inflammation, maintaining a low pacing threshold and high sensing capability. The lithium iodide battery remains the mainstay of implantable pacemaker systems, exhibiting a multiple-year lifespan, slow terminal decay, and a reduced size and cost of production. Although Greatbatch's first successful pacemaker implantation remains a seminal scientific contribution to modern cardiovascular disease management, emerging developments in this field may challenge its preeminence. Important challenges such as imaging compatibility, lead durability, and infection prevention are being addressed. Novel concepts such as leadless and biologic pacing are under active investigation. In conclusion, Greatbatch's historic achievement 50 years ago reminds us that technologic progress is timeless, as efforts to enhance clinical outcomes and the quality of life continue unimpeded into the 21st century. PMID:21391322

  2. 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.)

  3. 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

  4. 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)

  5. 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 %

  6. 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

  7. 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.)

  8. Biological safety evaluation of 125I-filled carbon nanotubes covered with metallic esophageal stent

    Objective: To evaluate the biological safety of 125I-filled carbon nanotubes covered with metallic esophageal stent with regard to the normal esophagus before clinical application. Methods: 125I-filled carbon nanotubes covered with metallic esophageal stent was prepared.Eighteen of New Zealand rabbits were randomly divided into three groups with 6 rabbits in each group. Three groups of stents, non-radioactive, low radio-activity (3.7-5.6 MBq), and high activity (11.1-13.0 MBq) were placed in the midpiece of esophagus of rabbits. Esophagus opacification and three-dimensions DSA were performed at 0.5 h, 7, 14 and 30 d after insertion of the stents, respectively. The rabbits were killed at 30 d after insertion of the stents, and histologic examinations of the esophageal walls were performed. Results: In non-radioactive and low activity groups, 1 of 6 rabbits died of wound infection at 1 and 3 d after surgery due to pulmonary infection, respectively. All specimens were obtained from 16 rabbits. Microscopically, in all rabbits of low activity and high activity groups, there were membrana mucosa necrotic and swell and breakage of the muscle fiber in esophageal submucosa and muscularis, submucosal inflammation, which were more severe in high activity group.In low activity group, one esophagus ectal membrane was involved, however, esophageal perforation did not develop. In high activity group, 3 of 6 rabbits esophageal perforation had developed, in which one esophagus mediastinum fistula developed, without inflammation. In non-radioactive group, it was almost normal in mucosa layer, a small amount of inflammatory cells were found in submucosal layer, and part of muscle fibers was fractured and no pathological changes of necrosis was found. Conclusions: Radioactive 125I carbon nanotubes covered metallic stent with low activity (3.7 -5.6 MBq) can be used as intraluminal palliative brachytherapy, which is safe and effective. (authors)

  9. 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.

  10. Scintillation Studies of the Mouse Mammary Tumor Virus with ^125I

    Yazdi, Amir; Blue, Eric; Bradley, Eric; Majewski, Stan; Mohammed, Shira; Qian, Jianguo; Saha, Margaret; Schworer, Stephen; Sutton, Jonathan; Weisenberger, Andrew; Welsh, Robert

    2007-10-01

    We have applied the techniques of scintillation imaging to studies of the mouse mammary tumor virus (MMTV). In these studies, Sodium Iodide Symporter (NIS) transfers the radioactive ^125I to the mammary glands of lactating mice and in particular to those mammaries with visible tumors. These studies have principally been carried out using pixellated scintillators coupled to position sensitive photomultiplier tubes (PSPMTs). More recently, we have initiated such studies with a monolithic slab of LaBr3 scintillator coupled to an array of PSPMTs. Several techniques of mapping and measuring the development of such tumors have been employed. These will be discussed in detail and preliminary results will be reported.

  11. 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)

  12. 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

  13. 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)

  14. 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

  15. 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)

  16. 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.

  17. 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

  18. 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

  19. Optimal implantation depth and adherence to guidelines on permanent pacing to improve the results of transcatheter aortic valve replacement with the medtronic corevalve system: The CoreValve prospective, international, post-market ADVANCE-II study

    Petronio, Anna S; Sinning, Jan-Malte; Van Mieghem, Nicolas; Zucchelli, Giulio; Nickenig, Georg; Bekeredjian, Raffi; Bosmans, B.; Bedogni, Francesco; Branny, Marian; Stangl, Karl; Kovac, Jan; Schiltgen, Molly; Kraus, Stacia; De Jaegere, Peter

    2015-01-01

    textabstractObjectives The aim of the CoreValve prospective, international, post-market ADVANCE-II study was to define the rates of conduction disturbances and permanent pacemaker implantation (PPI) after transcatheter aortic valve replacement with the Medtronic CoreValve System (Minneapolis, Minnesota) using optimized implantation techniques and application of international guidelines on cardiac pacing. Background Conduction disturbances are a frequent complication of transcatheter aortic va...

  20. Enhancement of lethal effect of 5-125I-Iodo-2'-deoxyuridine by a balanced deoxyribonucleoside mixture

    Objective: A potential anti-tumor agent, 5-125I-Iodo-2'-deoxyuridine (UdR), was cellular cycle dependent. The experiment was thus designed trying to enhance the lethal effect of UdR by a balance deoxyribonucleoside mixture (AUCG). Methods: After adding into medium of rat C6 cells with the mixture of 125I-UdR (74 kBq/ml) and AUCG at different concentrations, the survival fractions (SF) were determined using plating efficiency assay. The enhancement, meanwhile, was observed through transmission electron microscope (TEM) and DNA agarose gel electrophoresis. Results: Compared to control, the SF decreased in cells treated with AUCG (P125I-UdR (74 kBq/ml) and AUCG (30 μmol/L). Conclusion: AUCG might enhance the lethal effect of 125I-UdR through apoptosis of C6 cells. (authors)

  1. Pharmacokinetics of 125I-labelled recombinant epidermal growth factor after intravenous injection of the drug in rabbits

    125I-rhEGF was prepared by Iodogen method. Purity was (97.1 +- 0.45)% as determined by SDS-PAGE. The results revealed that plasma radioactivities remained at high level within 8 hours, while fraction of 125I-rhEGF determined by RHPLC decreased rapidly and 125I labelled hydrophilic fraction increased simultaneously. Concentration-time curve of 125I-rhEGF was best fitted with two-compartment model. Disintegration half-lives were 9 min and 11.6 h, respectively. Levels in tissues were urine>thyroid gland>contents in jejunum>kidneys>plasma>bile>submaxillary glands>lungs. A total of (20.3 +- 5.1)% of injected radioactivity was excreted through urine within 8 h

  2. Repair of the double-strand breaks produced by 125I disintegrations in the DNA of micrococcus radiodurans

    Wild-type M. radiodurans and two radiosensitive mutants were used to study the lethal effects of 125I disintegrations in their DNA. The relative sensitivities of these three strains to inactivation by γ-radiation were reflected in their relative sensitivities to inactivation by 125I decay. The number of double-strand (ds) breaks in the DNA appeared to be similar at levels of γ-radiation and of 125I decay that reduced survival to 10%. All three strains of M. radiodurans rapidly repaired ds breaks produced in their DNA by either γ-radiation or 125I disintegrations. If one ds break per cell is a lethal event [Krisch. et al., 1975], cells of the three strains tested would die when they had left unrepaired one ds break out of an initial 45, 600 or 1800 ds breaks per single cell. (Auth.)

  3. Inhibition of human prostate cancer xenograft growth by 125I labeled triple-helin forming oligonucleotide directed against androgen receptor

    ZHANG Yong; MA Yi; LU Han-ping; GAO Jin-hui; LIANG Chang-sheng; LIU Chang-zheng; ZOU Jun-tao; WANG Hua-qiao

    2008-01-01

    Background The failure of hormone treatment for advanced prostate cancer might be related to aberrant activation of the androgen receptor.We have shown that 125I labeled triple-helix forming oligonucleotide (TFO) against the androgen receptor gene inhibits androgen receptor expression and cell proliferation of LNCaP prostate cancer cells in vitro.This study aimed at exploring the effects of the 125I-TFO on prostate tumor growth in vivo using a nude mouse xenograft model.Methods TFO was labeled with 125I by the iodogen method.Thirty-two nude mice bearing LNCaP xenograft tumors were randomized into 4 groups and were intratumorally injected with 125I-TFO,unlabeled TFO,Na125I and normal saline.Tumor size was measured weekly.The tumor growth inhibition rate (RI) was calculated by measurement of tumor weight.The expression of the androgen receptor gene was performed by RT-PCR and immunohistochemical study.The prostate specific antigen (PSA) serum levels were measured by enzyme linked immunosorbent assay.The tumor cell apoptosis index (Al) was detected by TUNEL assay.Results Tumor measurements showed that tumor development was significantly inhibited by either 125I-TFO or TFO,with tumor RIs of 50.79% and 32.80% respectively.125I-TFO caused greater inhibition of androgen receptor expression and higher Als in tumor tissue than TFO.Both the tumor weight and the PSA serum levels in 125I-TFO treated mice ((0.93±0.15) g and (17.43±1.85) ng/ml,respectively) were significantly lower than those ((1.27±0.21) g and (28.25±3.41)ng/ml,respectively) in TFO treated mice (all P<0.05).Na125I did not significantly affect tumor growth and androgen receptor expression in tumor tissue.Conclusions The 125I-TFO can effectively inhibit androgen receptor expression and tumor growth of human prostate cancer xenografts in vivo.The inhibitory efficacy of 125I-TFO is more potent than that of TFO,providing a reference for future studies of antigen radiotherapy.

  4. Autoradiographic localization of (/sup 125/I)-angiotensin II binding sites in the rat adrenal gland

    Healy, D.P.; Maciejewski, A.R.; Printz, M.P.

    1985-03-01

    To gain greater insight into sites of action of circulating angiotensin II (Ang II) within the adrenal, we have localized the (/sup 125/I)-Ang II binding site using in vitro autoradiography. Autoradiograms were generated either by apposition of isotope-sensitive film or with emulsion-coated coverslips to slide-mounted adrenal sections labeled in vitro with 1.0 nM (/sup 125/I)-Ang II. Analysis of the autoradiograms showed that Ang II binding sites were concentrated in a thin band in the outer cortex (over the cells of the zona glomerulosa) and in the adrenal medulla, which at higher power was seen as dense patches. Few sites were evident in the inner cortex. The existence of Ang II binding sites in the adrenal medulla was confirmed by conventional homogenate binding techniques which revealed a single class of high affinity Ang II binding site (K/sub d/ . 0.7nM, B/sub max/ . 168.7 fmol/mg). These results suggest that the adrenal medulla may be a target for direct receptor-mediated actions of Ang II.

  5. Composition of cross-linked 125I-follitropin-receptor complexes

    Both of the alpha and beta subunits of intact human follitropin (FSH) were radioiodinated with 125I-sodium iodide and chloramine-T and could be resolved on sodium dodecyl sulfate-polyacrylamide gels. Radioiodinated FSH was affinity-cross-linked with a cleavable (nondisulfide) homobifunctional reagent to its membrane receptor on the porcine granulosa cell surface as well as to a Triton X-100-solubilized form of the receptor. Cross-linked samples revealed three additional bands of slower electrophoretic mobility, corresponding to 65, 83, and 117 kDa, in addition to the hormone bands. The hormone alpha beta dimer band corresponded to 43 kDa. Formation of the three bands requires the 125I-hormone to bind specifically to the receptor with subsequent cross-linking. Binding was prevented by an excess of the native hormone but not by other hormones. A monofunctional analog of the cross-linking reagent failed to produce the three bands. Reagent concentration-dependent cross-linking revealed that their formation was sequential; smaller complexes formed first and then larger ones. When gels of cross-linked complexes were treated to cleave covalent cross-links and then electrophoresed in a second dimension, 18-, 22-, and 34-kDa components were released, in addition to the alpha and beta subunits of the hormone

  6. DNA strand breakage by 125I decay: Plasmid DNA in dilute aqueous solution

    The question of the extent of damage to DNA, in particular double strand breaks, that can be caused by the decay of the Auger emitter 125I when it is covalently incorporated into the DNA requires resolution. In particular, experiments with plasmid DNA reported by Linz and Stoecklin would seem to indicate that the range of effect extends over the whole length of the molecule (a few 1,000's base pairs (bp)) in contrast to the generally accepted view that the decay is very localized (i.e. effect over a few 10's bp). This raises the question of whether a long range energy migration process is operative in DNA or whether the fragmentation can be accounted for by free radical diffusion. The authors report here experiments to help resolve this issue by investigating and trying to eliminate the possible effects of free radicals. The results which are broadly consistent with the findings of Linz and Stoecklin indicate that long-range damage in labeled DNA in aqueous solution is due to effects of free radicals. The authors confirm the high-LET nature of the 125I decay

  7. Radiation complications and tumor control after 125I plaque brachytherapy for ocular melanoma

    Purpose: To determine the outcome of 125I plaque brachytherapy at our institution and identify the risk factors associated with the development of radiation complications, tumor recurrence, and metastasis. Patients and Methods: From 1986 to 2000, 156 patients underwent 125I episcleral plaque (COMS design) application for the treatment of ocular melanoma. Chart analysis of follow-up ophthalmologic appointments assessed the incidence of ocular side effects after therapy. Statistical analysis assessed outcomes and significant influencing factors. Results: With a median follow-up of 6.2 years, the 5-year overall survival was 83%. The 5-year disease-specific survival was 91%. Initial local control at 5 years was 92%, with 100% ultimate local control after secondary therapy that included 9 enucleations. The risk of metastasis was 10% at 5 years and 27% at 10 years. Vision stayed the same or improved in 25% of patients, and 44% of patients maintained visual acuity better than 20/200. Thirteen percent of patients experienced chronic pain or discomfort in the treated eye. Dose rates to the tumor apex greater than 90 to 100 cGy/h were associated with increased systemic control but worse radiation toxicity. Conclusion: Patients in our series experienced excellent local tumor control. Higher dose rates to the tumor apex were associated with reduced rates of distant metastases but worse ocular function

  8. Enhancement of cetuximab on radiosensitivity of colorectal cancer cells exposed to 125I seeds

    Objective: To investigate the effect of cetuximab (C225) on the radiosensitivity of colorectal cancer cells CL187 and underlying mechanism. Methods: Cell survival was detected by colony forming assay. The levels of apoptosis and cell cycle distribution were determined by flow cytometer. The mitotic ratio was measured by Wright's-Giemsa mixed coloring method. The protein levels of Bax and Bcl2 were detected by Western blot. Results: The sensitizing enhancement ratio of C225 was approximately 1.4. C225 treatment and 125I seed radiation induced G1 cell cycle arrest individually. C225 increased the radiation-induced apoptosis (t =6.6, P<0.05) and cellular Bax/Bcl-2 ratio (t =9.4, P<0.05), but did not increase radiation-induced G1 arrest. In addition, there was no difference in mitotic index among different groups. Conclusions: C225 sensitizes CL187 to 125I seed irradiation,which might be related with increase of radiation-induced apoptosis. (authors)

  9. A 125I-protein A-binding assay detecting antibodies to cell surface antigens

    A 125I-protein A-binding assay detecting antibodies to cell surface antigens on human blood cells was developed and evaluated using sera from multitransfused nonleukemic patients sensitized against HLA antigens. The binding assay was found to be reproducible and more sensitive than conventional HLA testing. Seven patients with acute myelogenous leukemia and two patients with acute lymphoblastic leukemia successfully treated by chemotherapy were than investigated. Sera from seven of the patients studied in partial or complete remission demonstrated significant binding to autochthonous leukemic cells obtained from bone marrow or peripheral blood. In two cases sera taken during the leukemic stage demonstrated the most pronounced binding to the patients' own leukemic cells. Sera from four patients with demonstrable significant binding to autochthonous leukemic cells failed to bind to autochthonous remission cells when both types of target cells were tested in parallel. Differences in serum concentrations of IgG, IgA, and IgM were not the cause of the demonstrated increased binding of leukemic sera to autochthonous target cells. We propose that the 125I-protein A-binding assay presented in this paper detects antibodies reacting selectively with acute leukemia cells. (orig.)

  10. Immunoassay using 125I- or enzyme-labeled protein A and antigen-coated tubes

    Antigen-coated plastic tubes were used with 125I- or enzyme-labeled stapylococcal protein A in a general immunoassay method for antigens and haptens. Protein A reacts with immunoglobulin G(IgG) regardless of antibody specificity at sites distal to the antigen combining site and does not inhibit the immune reaction. It therefore serves as a general tracer and its use eliminates the need to purify and to label individual components for each assay. Macromolecular antigens were bound to polystyrene or polypropylene tubes by direct passive absorption. Haptens with free carboxyl groups were bound covalently to poly-L-lysine and these conjugates passively absorbed to the tube surface. Optimal assay conditions were established for the quantitative determination of immunoglobulins and the folate derivatives, methotrexate and 5-methyltetrahydrofolate, using 125I-labeled protein A or protein A labeled with alkaline phosphatase. The method has been used to estimate levels of IgG, IgA, Igm, and IgE in serum in volumes up to 1 ml

  11. New technique of investigating the kidney function in infants using 125I-hippuran

    A scanner is described with an optimized profilographic detection system which allows to examine the relative position of the kidneys, their function and the filling of the bladder in infants and toddlers using 125I-hippuran or radiopharmaceuticals labelled with 99mTc. The chosen design of the apparatus eliminates the shortcomings of existing renographic examinations and considerably increases the validity of investigations. The scanned field is sufficiently large to take the entire abdominal cavity of infants and toddlers. There is thus no need to know the position of the kidneys and the bladder and there is no need to adjust collimated detectors above the kidneys. The high sensitivity of the scanner allows to evaluate the results from the screen of a multi-channel analyzer during applications of 125I-hippuran with an activity level of over 100 kBq without adjustment data and of under 74 kBq with data smoothing. The radiation burden of the examined child is thereby reduced to approximately one quarter. (Z.M.). 6 figs., 3 tabs., 7 refs

  12. Plasma kinetics of 125I beta endorphin turnover in lean and obese Zucker rats

    Plasma clearance kinetics for Beta Endorphin (BEP) are not well-defined and no definitive data exist for lean versus obese animals. To determine such kinetic parameters, a bolus of 125I BEP (1μCi/kg) was infused into awake lean(L) and obese(O) Zucker rats. Arterial blood samples were withdrawn initially at 20 seconds intervals and less frequently as a 3-hour experimental period progressed. Donor rat blood was infused (venous catheter) to replace withdrawn blood. At 180 minutes approximately 10% of the initial dose remained in the plasma. Clearance kinetics for 125I BEP were analyzed by compartmental analysis. A 3-component equation (i.e., 3 compartment model) provided the best fit for both L and O groups. Plasma transit times were very rapid; however, plasma fractional catabolic rate was low. Plasma mean residence time was similar for both groups (50 minutes) as was recycle time. These data suggest that BEP kinetics are similar in L and O rats, and that this peptide may undergo extensive recycling into and out of the plasma compartment. The identity of the other two compartments requires further investigation

  13. On-line I-/Te- separation for the AMS analysis of 125I

    Charles, C. R. J.; Cornett, R. J.; Zhao, X.-L.; Litherland, A. E.; Kieser, W. E.

    2015-10-01

    The isobar separator for anions (ISA) was used together with a 3 MV tandem accelerator mass spectrometer (AMS) to demonstrate the real time (on-line) separation of Te- from I-. Following the ion source mass spectrometry and major retardation to tens of eV, the ISA uses a radiofrequency quadrupole (RFQ) ion guide to confine and direct I- and associated Te- isobar anions through a gas-reaction cell, where chemical reactions occur at eV energies with the electronegative gas NO2. Anions are subsequently reaccelerated out of the ISA to near original ion source extraction energies for AMS analysis. At 5 mTorr NO2 in the ISA gas-reaction cell, 125Te- was observed to be attenuated by a factor of ∼107 as compared to 127I- that did not experience significant (107 relative to 37Cl- under the same ISA-AMS conditions. The preferential destruction of Te- (and S-) at eV energies in the ISA is likely due to a larger favorable destruction cross-section with NO2. This study is the first demonstration of I-Te anion separation for AMS, and makes possible the use of 125I, free of the contaminant 125Te isobar after suitable sample purification, for future 129I/125I carrier-free analyses of natural samples at ultra-low trace levels.

  14. Autoradiographic distribution of 125I-galanin binding sites in the rat central nervous system

    Galanin (GAL) binding sites in coronal sections of the rat brain were demonstrated using autoradiographic methods. Scatchard analysis of 125I-GAL binding to slide-mounted tissue sections revealed saturable binding to a single class of receptors with a Kd of approximately 0.2 nM. 125I-GAL binding sites were demonstrated throughout the rat central nervous system. Dense binding was observed in the following areas: prefrontal cortex, the anterior nuclei of the olfactory bulb, several nuclei of the amygdaloid complex, the dorsal septal area, dorsal bed nucleus of the stria terminalis, the ventral pallidum, the internal medullary laminae of the thalamus, medial pretectal nucleus, nucleus of the medial optic tract, borderline area of the caudal spinal trigeminal nucleus adjacent to the spinal trigeminal tract, the substantia gelatinosa and the superficial layers of the dorsal spinal cord. Moderate binding was observed in the piriform, periamygdaloid, entorhinal, insular cortex and the subiculum, the nucleus accumbens, medial forebrain bundle, anterior hypothalamic, ventromedial, dorsal premamillary, lateral and periventricular thalamic nuclei, the subzona incerta, Forel's field H1 and H2, periventricular gray matter, medial and superficial gray strata of the superior colliculus, dorsal parts of the central gray, peripeduncular area, the interpeduncular nucleus, substantia nigra zona compacta, ventral tegmental area, the dorsal and ventral parabrachial and parvocellular reticular nuclei. The preponderance of GAL-binding in somatosensory as well as in limbic areas suggests a possible involvement of GAL in a variety of brain functions

  15. Search for 17-keV neutrinos in the internal bremsstrahlung spectrum of 125I

    We have conducted an experiment to search for the signature of a 17-keV neutrino in the internal bremsstrahlung (IB) spectrum of 125I. Gamma rays from a ∼ 100 mCi 125I point source were counted in a planar HPGe detector which is 16 mm in diameter and 10 mm in depth and which has a resolution of 560 eV at 122 keV. The source was counted for 61 d and the background for 17 d. At the start of the counting period the count rate was 650 s-1; the number of counts 17 keV below the 2p endpoint is 106 per keV. Data in the energy interval 120-150.5 keV were fitted with a theoretical spectrum calculated using nonrelativistic Hartree-Fock atomic wavefunctions. The preliminary fits reject the hypothesis of a 0.8% 17-keV neutrino at a confidence level of ≥ 98%. We are in the process of reanalyzing the data using recent relativistic theoretical shapes

  16. DNA strand breakage by 125I-decay in a synthetic oligodeoxynucleotide. Fragment distribution and evaluation of DMSO protection effect

    A double stranded oligodeoxynucleotide containing a single 125I-dC in a defined location was used to investigate DNA strand breakage resulting from 125I decay. Samples of a 41 bp oligodeoxynucleotide were incubated in 20 mM phosphate buffer (PB), or PB plus 2 M dimethylsulphoxide (DMSO), at 4 C during 18-20 days. The 32P-5'-end labelled DNA fragments produced by 125I decays were separated on denaturing polyacrylamide gels, and the 32P activity in each fragment was determined by scintillation counting after elution of fragments from gel. Most of the breaks, around 90%, occurred within 4-5 nucleotides of the 125I-dC, but DNA breaks were detected up to 16 nucleotides from the decay site. The 125I-dC was located at the 21st nucleotide from the 32P-5'-end label, and since 32P was not detected in fragments longer than 20 nucleotides, it was assumed that all 125I decay events produce at least one break in the 125I-labelled DNA strand. The results show a considerable protection effect of DMSO on DNA breaks at sites >5-6 nucleotides from the 125I location. The probability of breaks in this region was decreased with DMSO by a factor of 2 to 8-fold, suggesting significant role for radical-mediated DNA breaks at the more distant sites. However, the total protection effect of DMSO is rather small: 1.1, because of the small contribution of breakage at distant sites to the total yield. (orig.)

  17. Heterogeneity in mouse seminal vesicle epithelial cells responding to androgen as evaluated by incorporation of [125I]iododeoxyuridine

    When the uptake of 5-[125I]iodo-2'-deoxyuridine ([125I]IdUrd) into the seminal vesicle of castrated mice was measured 3 days after starting injections of various doses of testosterone propionate (TP), logarithmic values of [125I]IdUrd uptake were proportional to the logarithmic doses of TP in the range of 0.04-2 micrograms/g BW. The [125I]IdUrd uptake values correlated well with the labeling and mitotic indices of epithelial cells. Since daily injections of 0.4 microgram TP/g BW did not increase significantly the weight or DNA content or protein content of the seminal vesicle, the [125I]IdUrd uptake is a sensitive index of androgen action. Moreover, this suggests that low doses of androgen induce division of epithelial cells without resulting in the increase in cell number. The [125I]IdUrd radioactivity in the seminal vesicle was measured 2-15 days after the injection of [125I]IdUrd, since the value represented the fraction of surviving cells synthesizing DNA at the time of [125I]IdUrd injection. When injections of 4 micrograms TP/g BW were continued, the incorporated radioactivity was retained. In contrast, continuous injections of 0.2 microgram TP/g BW did not maintain the radioactivity, of which incorporation was induced by the same dose of TP. Thus, the present result suggests the presence of heterogeneity in androgen-responsive epithelial cells of the seminal vesicle

  18. The effect of 125I labeled anti-androgen receptor agent on the proliferation of prostate cancer cells

    Objective: Based on the previous experience of using anti-androgen receptor triple helix forming oligonucleotide (TFO) to inhibit proliferation of prostate cancer cells, a 125I labeled TFO was prepared and tested in this experiment as an androgen receptor targeted antigene radiotherapy. Methods: 125I-TFO was labeled through Iodogen and then transfected LNCaP prostate cancer cells via liposome. The unlabeled TFO, 125I, and naturally cultured cells served as controls. The cellular proliferation was detected by methyl thiazolium tetrazolium (MTT) method, the expression of androgen receptor gene was carried out by RT-PCR and immunohistochemical study. Results: The radiolabeling efficiency, radiochemical purity and specific activity of 125I-TFO were 63.7%, 95.6% and 80.1 kBq/μg, respectively. At the same TFO concentration, the androgen receptor expression level in 125I-TFO treated cells was markedly lower than that of TFO group (P125I-TFO on cellular proliferation was significantly higher (P< 0.01). Conclusion: The inhibitory effect on androgen receptor expression and cell proliferation of prostate cancer cells of antigene therapy with radio-labeled TFO were significantly more obvious than that of classical antigene therapy. (authors)

  19. Effects of 125I seed on apoptosis and cell cycle of esophageal carcinoma Eca-109 cell line

    To determine the effects of 125I seed on apoptosis and cell cycle of esophageal carcinoma Eca-109 cell line in vitro, cells were divided randomly into four groups: untreated cell (group A), treated cell with 0.2mCi 125I seed (group B), treated cell with 0.4mCi 125I seed (group C) and treated cell with 0.8mCi 125I seed (group D). After 7 days, the apoptosis and cell cycle of Eca-109 cells were detected by flow cytometry. The results showed that the apoptosis index (AI) in group B, C and D were statistically higher than that of control group A (P 0.05). G2/M phase cells increased with the dose enhancing of the 125I seed(P125I seed could induce apoptosis of esophageal carcinoma cells Eca-109 in vitro, and it may work through cell cycle G2/M phase block. (authors)

  20. Radiosynthesis, in vitro cellular uptake and in vivo biodistribution of 3'-O-(3-benzenesulfonylfuroxan-4-yl)-5-[{sup 125}I]iodo-2'-deoxyuridine, a nucleoside-based nitric oxide donor

    Moharram, Sameh [Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, Alberta, T6G 2N8 (Canada); Zhou, Aihua [Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, Alberta, T6G 2N8 (Canada); Kumar, Piyush [Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, Alberta, T6G 2N8 (Canada); Knaus, Edward E. [Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, Alberta, T6G 2N8 (Canada); Wiebe, Leonard I. [Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, Alberta, T6G 2N8 (Canada)]. E-mail: leonard.wiebe@ualberta.ca

    2005-08-01

    Introduction: 3'-O-(3-Benzenesulfonylfuroxan-4-yl)-5-iodo-2'-deoxyuridine (1) is a cytotoxic nitric oxide (NO) donor-nucleoside dual action prodrug designed to exploit both NO and an antimetabolite nucleoside for cancer therapy. Methods: 1 was radiolabeled by radioiodide exchange and purified by HPLC in 16% overall radiochemical yield. The specific activity of [{sup 125}I]1 was 31.8 {mu}Ci/{mu}g (680 MBq/{mu}M). Protein binding, deiodination, cellular uptake and incorporation of 1 into cellular nucleic acids were measured by standard methods, and its in vivo biodistribution was determined in Balb/c mice bearing implanted EMT-6 tumors following intravenous injection. Results: [{sup 125}I]1 degraded rapidly during the in vitro tests, thus impeding unequivocal assessment but indicating that it was only weakly protein bound and that it was resistant to deiodination under test conditions. Uptake of [{sup 125}I]1 by murine tumor cells (KBALB and KBALB-STK) in vitro was low ({approx}17 fmol/{mu}g protein over 2 h) with only {approx}0.3% (0.04-0.06 fmol/{mu}g protein) of total uptake present in the DNA fraction. In the murine tumor model, liver, kidney, intestine and tumor showed the greatest uptake, with liver, intestine and blood all containing >5 injected dose per gram of tissue (%ID/g) during the 15-min to 2-h postinjection period. Maximum tissue/blood level ratios were 3.6 (2 h) for tumor and 6.4 (24 h) for liver. Low uptake in thyroid and stomach was indicative of minimal in vivo deiodination. Conclusions: [{sup 125}I]1 undergoes only minimal deoiodination under both in vitro and in vivo conditions. Under conditions of the in vitro NO release assay, 1 reacts to produce a single, major, unstable adduct that decomposes upon workup. Protein binding of [{sup 125}I]1 could not be assessed because of similar chemical reaction with albumin. Incorporation of radioactivity into the cellular nucleic acid fraction was low, and in vivo distribution of [{sup 125}I]1 was

  1. 125I-UdR瘤内注射治疗Lewis肺癌荷瘤小鼠效果观察%Therapeutic effect of intratumoral injection using 125I-UdR on Lewis lung cancer

    李智勇; 刘增礼; 吴锦昌; 周俊东; 申咏梅; 劳勤华

    2013-01-01

    目的 研究125I标记脱氧尿嘧啶核苷(125I-UdR)在Lewis肺癌荷瘤小鼠模型治疗中的药物分布、用药安全性和治疗效果.方法 在Lewis肺癌荷瘤小鼠模型瘤内注射125I-UdR(3.7 MBq/10 μL),通过γ-计数器测量各脏器放射性活度和SPECT显像来观察125I-UdR的药物分布;分析用药后外周血象、肝肾功能等指标及骨髓象来评价125I-UdR的安全性;观察用药后瘤体的组织细胞学变化并作生存分析.结果 125I-UdR局部注射后可在瘤内持续浓聚并致肿瘤细胞坏死;其外周血象、肝肾功能和骨髓象无明显变化,接受治疗的荷瘤鼠生存期明显延长.结论 荷瘤鼠瘤内注射125I-UdR治疗Lewis肺癌安全有效.%Objective To investigate the distribution,safety and therapeutic effect of 125I-UdR (5-[125I] Iodo-2-deoxyuridine) (3.7 MBq/10 ul) in C57 BL/6 mice bearing Lewis lung cancer.Methods After 125I-UdR intratumoral injection,the radioactivity of various organs was determined by γ-well counter and the distribution of 125 I-UdR was observed by SPECT scintigraphy; the safety of 125 I-UdR was analyzed by observing peripheral hemogram,marrow cell and blood biochemistry indexes; the changes of histology and cytology of the tumor were observed and the survival rate was analyzed.Results 125I-UdR was persistently stayed in the tumor,and led to tumor necrosis after partly intratumoral injection.Mice hemogram,marrow cell,hepatic and renal function had no obvious changes,and the survival time of tumor-bearing mice treated by 125 I-UdR distinctly was extended.Conclusion It is safe and effective to inject 125I-UdR (3.7 MBq/10 ul) into the transplanting tumor of tumor-bearing mice with Lewis lung cancer.

  2. Autoradiographic characterization of (+-)-1-(2,5-dimethoxy-4-[125I] iodophenyl)-2-aminopropane ([125I]DOI) binding to 5-HT2 and 5-HT1c receptors in rat brain

    The 5-HT2 (serotonin) receptor has traditionally been labeled with antagonist radioligands such as [3H]ketanserin and [3H]spiperone, which label both agonist high-affinity (guanyl nucleotide-sensitive) and agonist low-affinity (guanyl nucleotide-insensitive) states of this receptor. The hallucinogen 1-(2,5-dimethoxy-4-iodophenyl)-2-aminopropane (DOI) is an agonist which labels the high-affinity guanyl nucleotide-sensitive state of brain 5-HT2 receptors selectively. In the present study, conditions for autoradiographic visualization of (+/-)-[125I]DOI-labeled 5-HT2 receptors were optimized and binding to slide-mounted sections was characterized with respect to pharmacology, guanyl nucleotide sensitivity and anatomical distribution. In slide-mounted rat brain sections (+/-)-[125I]DOI binding was saturable, of high affinity (KD approximately 4 nM) and displayed a pharmacologic profile typical of 5-HT2 receptors. Consistent with coupling of 5-HT2 receptors in the high-affinity state to a guanyl nucleotide regulatory protein, [125I]DOI binding was inhibited by guanyl nucleotides but not by adenosine triphosphate. Patterns of autoradiographic distribution of [125I]DOI binding to 5-HT2 receptors were similar to those seen with [3H]ketanserin- and [125I]-lysergic acid diethylamide-labeled 5-HT2 receptors. However, the density of 5-HT2 receptors labeled by the agonist [125I]DOI was markedly lower (30-50%) than that labeled by the antagonist [3H]ketanserin. High densities of [125I]DOI labeling were present in olfactory bulb, anterior regions of cerebral cortex (layer IV), claustrum, caudate putamen, globus pallidus, ventral pallidum, islands of Calleja, mammillary nuclei and inferior olive. Binding in hippocampus, thalamus and hypothalamus was generally sparse

  3. Optimal implantation depth and adherence to guidelines on permanent pacing to improve the results of transcatheter aortic valve replacement with the medtronic corevalve system: The CoreValve prospective, international, post-market ADVANCE-II study

    A.S. Petronio (Anna S.); J.-M. Sinning (Jan-Malte); N.M. van Mieghem (Nicolas); G. Zucchelli (Giulio); G. Nickenig (Georg); R. Bekeredjian (Raffi); B. Bosmans; F. Bedogni (Francesco); M. Branny (Marian); K. Stangl (Karl); J. Kovac (Jan); M. Schiltgen (Molly); S. Kraus (Stacia); P.P.T. de Jaegere (Peter)

    2015-01-01

    textabstractObjectives The aim of the CoreValve prospective, international, post-market ADVANCE-II study was to define the rates of conduction disturbances and permanent pacemaker implantation (PPI) after transcatheter aortic valve replacement with the Medtronic CoreValve System (Minneapolis, Minnes

  4. Preliminary radiochemical and biological studies on the liposome encapsulated platinum-[125I]iodohistamine complex

    The platinum-iodohistamine complex with in vitro cytostatic activity toward colon and mammary cancer cells has been synthesised recently in our laboratory. The pharmacokinetics of radioactive complex analogues, labelled with I-131 and I-125, has been examined in murine model of spontaneous mammary adenocarcinoma. The present work is devoted to the examination of the potential use of liposomes as a carrier system for the radioactive platinum-[*I]iodohistamine complex in vivo. Encapsulations of the Pt-125I]iodohistamine were studied using a different molar ratio of the complex and liposomes with positive surface charge, as well as various incubation procedures. Biodistribution of the initial and the liposomal form of the complex were studied in C3H tumour-bearing mice with spontaneously developed and transplantable (16C) mammary adenocarcinoma. Comparative biodistribution studies in C3H/16C mice and in mice with spontaneously developed mammary tumour have shown that in the former model pharmacokinetics of the Pt-[125 I]iodohistamine complex is more predictable and more similar to that observed for cisplatin. Therefore, the transplantable tumour model is more advantageous for the complex and its liposomal form evaluation. In C3H/16C mice, significant differences in the biodistribution between the radioactive platinum complex and its liposomal form were observed. The concentration of the activity in blood after 2 h p.i.v. was two times lower for the encapsulated complex, and the uptake of the radioactivity by liver, spleen, and lungs was twice as high as that obtained for the free Pt-[125I]iodohistamine preparation. The radioactivity in tumour was almost constant for liposomal platinum complex (ca. 2% ID/g), although it was two times lower compared to the initial platinum complex. The results of the present study indicate that platinum-[*I]iodohistamine can be efficiently incorporated into cationic liposomes (c. 40%). However, the uptake of the encapsulated complex by

  5. Ganglioside inhibition of 125I-plasmin binding to colorectal carcinoma cells

    The pre-incubation of human colorectal carcinoma cells SW 1116 with 25 to 100 uM purified gangliosides resulted in 35-60% inhibition of specific 125I-plasmin binding to the cell surface. After 5 to 6 days in culture, tumor cells were pre-incubated at 4 degrees for 1 to 4 h followed by post-incubation with 125I-plasmin by techniques previously described. At 25 uM the capacity for inhibition of plasmin binding was GT1b greater than GQ1b greater than or equal to GD1a greater than GM1 less than or equal to GgOse 4Cer. Thus a terminal sialyl moiety appears to be necessary (p less than 0.05) although exogenous N-acetyl neuraminic acid was ineffective (p greater than 0.05), indicating a role for the lipid portion of the ganglioside. Other (glyco)lipids such as sphingosine, fucolipid H-1 and sulfatide were without significant effect. The inhibition could not be reversed by the presence of 10 mM Ca+2, EDTA, pre-treatment of the cell with carboxypeptidase or pretreatment of plasmin with neuraminidases. The inhibition was however reversed by post-incubation in control medium without exogenous ganglioside. Cell counts determined prior to, and after ganglioside incubation showed that the effect was not due to cell death or detachment from the culture surface. The dissociation constant for 125I-plasmin binding was 5.6 x 10(-8) M (700,000 sites/cell), but in the presence of trisialoganglioside (GT1b), Scatchard plots suggested diversification of binding sites with 280,000 sites/cell at Kd 2.6 x 10(-8) M and 820,000 sites/cell at Kd 2.1 x 10(-7) M. Another interpretation of the Scatchard plot in the presence of ganglioside was that the glycolipid imposed negative cooperativity on plasmin binding to the cell surface. These results suggest that certain gangliosides can affect tumor cell invasiveness by altering protease binding to the cell surface

  6. Dexamethasone effects on [125I]albumin distribution in experimental RG-2 gliomas and adjacent brain

    A total of 72 RG-2 transplanted gliomas were studied in 58 rats at three time points (1, 30, 240 min) after intravenous injection of [125I]radioiodinated serum albumin ([125I]RISA). The animals were divided into two groups: a control group that received no treatment and a second group that was treated with five doses of 1.5 mg/kg of dexamethasone over 2.5 days. Local tissue concentrations of [125I]RISA were measured with quantitative autoradiography based on morphological features of the tumors and used to calculate the tissue distribution space. Two models were used to analyze the data. A two compartment model yielded estimates of local blood-to-tissue influx constants (K1), lower limit extracellular volumes (Ve), and plasma vascular volumes (Vp) in different tumor regions. Treatment with dexamethasone consistently reduced the RISA distribution space in the RG-2 tumors; the reduction in Ve was statistically significant in almost all tumor regions: whole tumor Ve (mean +/- SE) was reduced from 0.14 +/- 0.02 ml g-1 in control animals to 0.08 +/- 0.01 ml g-1 in dexamethasone treated animals. K1 and Vp were also decreased in all tumor regions after treatment with dexamethasone (whole tumor K1 decreased from 2.36 +/- 0.89 to 0.83 +/- 0.29 microliter g-1 min-1 and Vp decreased slightly from 0.016 +/- 0.013 to 0.010 +/- 0.005 ml g-1 after dexamethasone treatment), but these changes were not statistically significant. A comparison of the tumor influx constants in control animals and the aqueous diffusion constants of two different size molecules (RISA and aminoisobutyric acid) suggests that the ''pores'' across RG-2 capillaries are large and may not restrict the free diffusion of RISA (estimated minimum pore diameter greater than 36 nm) and that the total pore area is approximately 6.2 X 10(-5) cm2 g-1 in RG-2 tumor tissue

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

    Hofmann, G.E.; Siddiqi, T.A.; Rao, Ch. V.; Carman, F.R.

    1988-01-01

    Specific binding of /sup 125/I-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 AB diabetic (N = 12), and large for gestational age (N = 13) pregnancies was measured. In all pregnancy states, placentas bound approximately four times more /sup 125/I-hEGF than did fetal membranes (P<0.0001). There was no significant differnce in /sup 125/I-hEGF binding to fetal membranes from the various pregnancy states (P<0.05). /sup 125/I-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 (P<0.05). The binding to placentas from pregnancies complicated by White class AB diabetes or large for gestational age infants, on the other hand, was not significantly different from that to placentas from normal and appropriate for gestational age pregnancies. /sup 125/I-hEGF specific binding did not differ between placentas from intrauterine growth retarded or twin pregnancies (P<0.05). Placental and fetal membrane /sup 125/I-hEGF binding did not vary with fetal sex, maternal race, placental weight, or gestational age between 37 to 42 weeks (P<0.05). Placental but not fetal membrane /sup 125/I-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.

  8. /sup 125/I-peptide mapping of protein III isolated from four strains of Neisseria gonorrhoeae

    Judd, R.C.

    1982-08-01

    Gonococcal outer-membrane protein I (PI) and PIII were isolated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis from reduced and unreduced whole-cell and outer-membrane lysates of four strains of nonpiliated (P-), transparent (O-) Neisseria gonorrhoeae. These proteins were radioiodinated and digested with alpha-chymotrypsin. The resultant /sup 125/I-peptides were then resolved by high-voltage thin-layer electrophoresis, followed by ascending thin-layer chromatography, and visualized by autoradiography. Results corroborated previous observations regarding the structural relationships of PIs having different apparent subunit molecular weights. All PIIIs had very similar apparent primary structures, regardless of the strain from which they were isolated, the source (i.e., whole cells or outer membranes), or the reduction state of the sodium dodecyl sulfate lysates. By the techniques used, it appeared that PIII is structurally similar in all of the gonococcal strains studied, even though each strain had structurally unique PIs.

  9. Radioiodination and 125I-labeled peptide mapping of proteins on nitrocellulose membranes

    A rapid procedure for generating dozens of 125I-labeled peptide maps from a protein band excised from a single lane of a sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) gel has been developed. Proteins, which can be rapidly purified by 2 X SDS-PAGE separation, are electroblotted onto nitrocellulose paper (NCP) and located by aqueous naphthol blue-black staining. All subsequent steps of radioiodination, and enzyme or chemical cleavage, are carried out on the NCP making it possible to test a variety of cleavage reagents on the same protein sample. The resultant peptidic residues, which can be separated by thin-layer electrophoresis-thin-layer chromatography (2D TLE-TLC), SDS-PAGE, or HPLC, can be used in comparative studies or they can be recovered for further structural and immunological analyses

  10. 3H- and 125I-labelled imipramine derivatives for radioimmunoassay of tricyclic antidepressants

    3H-desmethyl imipramine was prepared by catalyzed reaction of a solution of the non-active substance with tritium gas. The radiochemical purity of the product was 97% and molar activity was 2.4 TBq/mol. Reduction methylation by formaldehyde in the presence of tritium gas was used to prepare 3H-imipramine from labelled desmethyl imipramine. The radiochemical purity of the product was 96% and molar activity 2.9 TBq/mol. A detailed description is presented of the preparation of desimipraminyl derivatives as is their iodination with 125I. The degree of inhibition in iodinated derivatives was found to be lower than in tritium labelled imipramine. (E.S.). 2 figs., 4 refs

  11. A radioimmunoassay for virus antibody using binding of 125I-labelled protein A

    An assay for virus antibodies using protein A from Staphylococcus aureus is described. Type B and type C RNA tumour viruses adsorbed on to polystyrene microtitre plate wells were incubated with antiserum and then with 125I-labelled protein A (I-pA) and bound radioactivity was determined. Technical details such as labelling, antigen concentration, storage of I-pA are reported. The specificity of the reaction was investigated in detail by competition experiments with purified unbound homologous viruses. This assay also proved to be sensitive for demonstration of autogenous immunity to both type B and type C RNA tumour viruses. A study using antisera against purified core and envelope virus proteins of mammary tumour and leukaemia viruses suggested that the reaction mainly involves surface antigens of the intact virions. (author)

  12. Indirect 125I-labeled protein A assay for monoclonal antibodies to cell surface antigens

    An assay for detection of monoclonal hybridoma antibodies against cell surface antigens is described. Samples of spent medium from the hybridoma cultures are incubated in microtest wells with cells, either as adherent monolayers or in suspension. Antibodies bound to surface antigens are detected by successive incubations with rabbit anti-immunoglobulin serum and 125I-labeled protein A from Staphylococcus aureus, followed by autoradiography of the microtest plate or scintillation counting of the individual wells. Particular advantages of this assay for screening hybridomas are: (1) commercially available reagents are used, (2) antibodies of any species and of any immunoglobulin class or subclass can be detected, and (3) large numbers of samples can be screened rapidly and inexpensively. The assay has been used to select hybridomas producing monoclonal antibodies to surface antigens of human melanomas and mouse sarcomas. (Auth.)

  13. Search for a 17 keV neutrino in the internal bremsstrahlung spectrum of 125I

    We have searched for evidence of the emission of a 17 keV neutrino in the internal bremsstrahlung (IB) spectrum accompanying the electron capture decay of 125I. The IB spectrum, recorded in a planar Ge detector, has 1.2x106 counts per keV at 17 keV below the 2p end point. We set an upper limit of 0.4% for the admixture of a 17 keV neutrino, at the 90% confidence level, and exclude a 0.8% admixture at the 99.6% confidence level. The QEC value is found to be 185.77±0.06 keV. We also find that the recent calculations of Suric et al., which employ relativistic self-consistent-field atomic wave functions, reproduce the shape and relative intensity of IB partial spectra within a few percent

  14. Binding studies of the antitumoral radiopharmaceutical 125I-Crotoxin to Ehrlich ascites tumor cells

    Silveira, Marina B.; Santos, Raquel G. dos [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil); Dias, Consuelo L. Fortes [Fundacao Ezequiel Dias (FUNED), Belo Horizonte, MG (Brazil)], e-mail: consuelo@pq.cnpq.br; Cassali, Geovanni D. [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Lab. de Patologia Comparada], e-mail: cassalig@icb.ufmg.br

    2009-07-01

    The development of tools for functional diagnostic imaging is mainly based on radiopharmaceuticals that specifically target membrane receptors. Crotoxin (Crtx), a polypeptide isolated from Crotalus durissus terrificus venom, has been shown to have an antitumoral activity and is a promising bioactive tracer for tumor detection. More specific radiopharmaceuticals are being studied to complement the techniques applied in the conventional medicine against breast cancer, the most frequent cause of death from malignant disease in women. Crtx's effect has been shown to be related with the overexpression of epidermal growth factor receptor (EGFR), present in high levels in 30 to 60% of breast tumor cells. Our objective was to evaluate Crtx as a tracer for cancer diagnosis, investigating its properties as an EGFR-targeting agent. Ehrlich ascites tumor cells (EAT cells) were used due to its origin and similar characteristics to breast tumor cells, specially the presence of EGFR. Crtx was labeled with 125I and binding experiments were performed. To evaluate the specific binding in vitro of Crtx, competition binding assay was carried out in the presence of increasing concentrations of non-labelled crotoxin and epidermal growth factor (EGF). Specific binding of 125I-Crtx to EAT cells was determined and the binding was considered saturable, with approximately 70% of specificity, high affinity (Kd = 19.7 nM) and IC50 = 1.6 x 10-11 M. Our results indicate that Crtx's interaction with EAT cells is partially related with EGFR and increases the biotechnological potential of Crtx as a template for radiopharmaceutical design for cancer diagnosis. (author)

  15. IRD/WBC Calibration Factor for 123I, 125I e 131I in vivo measurements

    Azeredo, A.; Dantas, A.; Dantas, B.; Lucena, E.; Hunt, J.

    2004-07-01

    The production of iodine isotopes in nuclear reactors and cyclotrons as well as the use and handling of non-sealed liquid sources of iodine in nuclear medicine services for diagnosis and treatment represent a significant risk of internal contamination for the professional staff. Iodine is metabolized after ingestion or inhalation and tends to deposit preferentially in the thyroid tissue. Individual monitoring in these cases can be carried out through in vivo bioassay techniques. To calibrate the detection systems for the iodine isotopes, anthropomorphic phantoms of neck and thyroid containing known amounts of 123I, 125I and 131I were developed. The IRD-CNEN Whole Body Counter uses a NaI(Tl)3X3 detector for 131I measurements and a HPGe module with two crystals, for the measurement of the isotopes 123 and 125. The NaI(Tl) detector operates in the energy range from 30 to 3000 keV and the HPGe system from 10 to 200 keV. The choice of the detection system to be used in the measurement is based on the photon energy emitted by each radionuclide. The thyroid phantom for the calibration of 123I uses 139Ce, which emits photons with energies very close to 123I but with a longer half-life (137 days). For the calibration of 125I, the same isotope was used since it presents a suitable half-life to perform the measurements (60 days). For the development of the 131I thyroid phantom, the same isotope 131 was used as the standard. All the calculated calibration factors obtained by this technique were compared with the factors obtained using the Visual Monte Carlo in vivo program that simulates mathematically the contamination and counting conditions and geometry. The results obtained by these two methods are in good agreement. (Author)

  16. IRD/WBC Calibration Factor for 123I, 125I e 131I in vivo measurements

    The production of iodine isotopes in nuclear reactors and cyclotrons as well as the use and handling of non-sealed liquid sources of iodine in nuclear medicine services for diagnosis and treatment represent a significant risk of internal contamination for the professional staff. Iodine is metabolized after ingestion or inhalation and tends to deposit preferentially in the thyroid tissue. Individual monitoring in these cases can be carried out through in vivo bioassay techniques. To calibrate the detection systems for the iodine isotopes, anthropomorphic phantoms of neck and thyroid containing known amounts of 123I, 125I and 131I were developed. The IRD-CNEN Whole Body Counter uses a NaI(Tl)3X3 detector for 131I measurements and a HPGe module with two crystals, for the measurement of the isotopes 123 and 125. The NaI(Tl) detector operates in the energy range from 30 to 3000 keV and the HPGe system from 10 to 200 keV. The choice of the detection system to be used in the measurement is based on the photon energy emitted by each radionuclide. The thyroid phantom for the calibration of 123I uses 139Ce, which emits photons with energies very close to 123I but with a longer half-life (137 days). For the calibration of 125I, the same isotope was used since it presents a suitable half-life to perform the measurements (60 days). For the development of the 131I thyroid phantom, the same isotope 131 was used as the standard. All the calculated calibration factors obtained by this technique were compared with the factors obtained using the Visual Monte Carlo in vivo program that simulates mathematically the contamination and counting conditions and geometry. The results obtained by these two methods are in good agreement. (Author)

  17. Binding studies of the antitumoral radiopharmaceutical 125I-Crotoxin to Ehrlich ascites tumor cells

    The development of tools for functional diagnostic imaging is mainly based on radiopharmaceuticals that specifically target membrane receptors. Crotoxin (Crtx), a polypeptide isolated from Crotalus durissus terrificus venom, has been shown to have an antitumoral activity and is a promising bioactive tracer for tumor detection. More specific radiopharmaceuticals are being studied to complement the techniques applied in the conventional medicine against breast cancer, the most frequent cause of death from malignant disease in women. Crtx's effect has been shown to be related with the overexpression of epidermal growth factor receptor (EGFR), present in high levels in 30 to 60% of breast tumor cells. Our objective was to evaluate Crtx as a tracer for cancer diagnosis, investigating its properties as an EGFR-targeting agent. Ehrlich ascites tumor cells (EAT cells) were used due to its origin and similar characteristics to breast tumor cells, specially the presence of EGFR. Crtx was labeled with 125I and binding experiments were performed. To evaluate the specific binding in vitro of Crtx, competition binding assay was carried out in the presence of increasing concentrations of non-labelled crotoxin and epidermal growth factor (EGF). Specific binding of 125I-Crtx to EAT cells was determined and the binding was considered saturable, with approximately 70% of specificity, high affinity (Kd = 19.7 nM) and IC50 = 1.6 x 10-11 M. Our results indicate that Crtx's interaction with EAT cells is partially related with EGFR and increases the biotechnological potential of Crtx as a template for radiopharmaceutical design for cancer diagnosis. (author)

  18. Localized whole eye radiotherapy for retinoblastoma using a 125I applicator, 'claws'

    Purpose: To treat children with retinoblastoma, who require whole eye radiotherapy, with a specially designed 125I applicator that irradiates the eye while sparing the surrounding tissues. Methods and Materials: Under general anesthesia, a pericorneal ring is attached to the 4 extraocular muscles, and 4 appendages, each loaded with 125I seeds, are inserted beneath the conjunctiva in-between each pair of muscles and attached anteriorly to the ring. Twenty-nine eyes were treated. Eighteen received a median dose of 28 Gy during 91 hours and 11 received 40 Gy during 122 hours, when the relative biologic effectiveness was taken as 1 instead of 1.5. Six had received prior chemotherapy. Results: Twenty-four eyes were followed up for 2-157 months (median 29). Although 22 eyes responded, local control was achieved in 13 patients, 3 of whom required additional treatment for new tumors; a further 3 required additional treatment for tumor recurrence as well as new tumors. One of these eyes was enucleated for neovascular glaucoma. All 6 Group I-III eyes and 6 of 18 Group V eyes were retained for 2-157 months (median 39), with good vision in 10 eyes. Three developed cataracts 7, 8, and 12 years later, 1 of which has been removed. Conclusions: This is a new way of irradiating the whole eye with a minimal dose to the surrounding tissues. The treatment time is only 5 days. It is effective in Groups I-III, but only 33% of Group V eyes retained vision. No late cosmetic defects occurred

  19. Separation of {sup 134}Cs and {sup 137}Cs from {sup 125}I solution for medical applications

    Ram, Ramu; Dash, Ashutosh [Bhabha Atomic Research Centre, Trombay, Mumbai (India). Isotope Production and Applications Div.; Banerjee, Dayamoy [Bhabha Atomic Research Centre, Trombay, Mumbai (India). Process Development Div.

    2015-06-01

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

  20. Disparate uptake of 99mTcO4- and 125I- in thyroid cells in culture

    Pertechnetate (99mTcO4-) is a large anion that is thought to be trapped but not organified by the thyroid. In order to determine its usefulness in discriminating trapping from organification in thyroid cell culture the uptake of 99mTcO4- has been compared to that of 125I- both in sheep thyroid cells and in FRTL5 cells, a functional rat thyroid cell line. We found that uptake of both isotopes was dependent on TSH or agents that raised intracellular cAMP levels and was displaceable with iodide in both cell types. However in the rat cell line 99mTcO4- uptake was up to eight-fold higher than 125I- uptake, and 99mTcO4- but not 125I uptake was doubled by methimazole treatment. A considerable proportion of 99mTcO4- but not 125I- taken up by the FRTL5 cell but not the sheep cells was precipitable with TCA. This proportion was increased by methimazole treatment. We also found marked differences in sensitivity to ouabain between the two cell types. These results illustrate the differences between species in 125I- and 99mTcO4- transport and support the concerns expressed by Socolow and Ingbar (1967) in using 99mTcO4- as a direct and precise indicator of iodide transport activity. (orig.)

  1. Autoradiographic localization of extrastriatal D2-dopamine receptors in the human brain using [125I]epidepride.

    Hall, H; Farde, L; Halldin, C; Hurd, Y L; Pauli, S; Sedvall, G

    1996-06-01

    Epidepride is a benzamide with high affinity for central D2- and D3-dopamine receptors. The anatomical distribution of [125I]epidepride binding was examined by autoradiography, using postmortem human whole-hemisphere cryosections. The density of [125I]epidepride binding sites was high in caudate nucleus and putamen. [125I]epidepride also labeled receptors in extrastriatal region such as in the pallidum, some thalamic nuclei, the neocortex, and the substantia nigra. The neocortical binding was heterogeneously distributed. In most cortical regions, binding sites were located in superficial layers (I-II). However, in basal levels of the occipital cortex, [125I]epidepride binding was located in a deeper layer, probably corresponding to layer V. Competition studies indicated that most of the [125I]epidepride binding represented predominantly D2-dopamine receptors, in striatal as well as in extrastriatal regions. The presence of extrastriatal D2-dopamine receptor populations is of particular interest for research on schizophrenia and antipsychotic drug action. PMID:8723716

  2. Distribution of 125I-neurotensin binding sites in human forebrain: Comparison with the localization of acetylcholinesterase

    The distribution of 125I-neurotensin binding sites was compared with that of acetylcholinesterase reactivity in the human basal forebrain by using combined light microscopic radioautography/histochemistry. High 125I-neurotensin binding densities were observed in the bed nucleus of the stria terminalis, islands of Calleja, claustrum, olfactory tubercle, and central nucleus of the amygdala; lower levels were seen in the caudate, putamen, medial septum, diagonal band nucleus, and nucleus basalis of Meynert. Adjacent sections processed for cholinesterase histochemistry demonstrated a regional overlap between the distribution of labeled neurotensin binding sites and that of intense acetylcholinesterase staining in all of the above regions, except in the bed nucleus of the stria terminalis, claustrum, and central amygdaloid nucleus, where dense 125I-neurotensin labeling was detected over areas containing only weak to moderate cholinesterase staining. At higher magnification, 125I-neurotensin-labeled binding sites in the islands of Calleja, supraoptic nucleus of the hypothalamus, medial septum, diagonal band nucleus, and nucleus basalis of Meynert were selectively associated with neuronal perikarya found to be cholinesterase-positive in adjacent sections. Moderate 125I-neurotensin binding was also apparent over the cholinesterase-reactive neuropil of these latter three regions. These data suggest that neurotensin (NT) may directly influence the activity of magnocellular cholinergic neurons in the human basal forebrain, and may be involved in the physiopathology of dementing disorders such as Alzheimer's disease, in which these neurons have been shown to be affected

  3. Benzodiazepine effect of {sup 125}I-iomazenil-benzodiazepine receptor binding and serum corticosterone level in a rat model

    Fukumitsu, Nobuyoshi [Proton Medical Research Center, University of Tsukuba, Ibaragi, 305-8575 (Japan)]. E-mail: gzl13162@nifty.ne.jp; Ogi, Shigeyuki [Department of Radiology, Jikei University School of Medicine, Tokyo, 105-8461 (Japan); Uchiyama, Mayuki [Department of Radiology, Jikei University School of Medicine, Tokyo, 105-8461 (Japan); Mori, Yutaka [Department of Radiology, Jikei University School of Medicine, Tokyo, 105-8461 (Japan)

    2005-01-01

    To test the change in free or unoccupied benzodiazepine receptor (BZR) density in response to diazepam, we investigated {sup 125}I-iomazenil ({sup 125}I-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 {sup 125}I-IMZ of the D (10) group were significantly lower (P<.05) than those of the D (0) group in the frontal, parietal and temporal cortices, globus pallidus, hippocampus, amygdala and hypothalamus. The serum corticosterone level ratio in the D (10) group was significantly lower than that in the D (0) group (P<.05). From the change in serum corticosterone levels, diazepam attenuated the psychological stress produced by the physical stress to animals in adjacent compartments. From the reduced binding of {sup 125}I-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 {sup 125}I-IMZ binding is strongly affected by administration of diazepam.

  4. {sup 125}I-iomazenil - benzodiazepine receptor binding and serum corticosterone level during psychological stress in a rat model

    Fukumitsu, Nobuyoshi E-mail: GZL13162@nifty.ne.jp; Ogi, Shigeyuki; Uchiyama, Mayuki; Mori, Yutaka

    2004-02-01

    To test the hypothesis that benzodiazepine receptor density decreases in response to stress, we correlated {sup 125}I-iomazenil ({sup 125}I-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 {sup 125}I-iomazenil of the 3-DAY and 5-DAY showed that {sup 125}I-iomazenil - benzodiazepine receptor binding was significantly reduced in the cortices, accumbens nuclei, amygdala and caudate putamen (p<0.05). Serum corticosterone level ratio appeared to be slightly elevated in 3-DAY and 5-DAY, although this elevation was not significant. These data suggest that {sup 125}I-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.

  5. Health-Related Quality of Life up to Six Years After 125I Brachytherapy for Early-Stage Prostate Cancer

    Purpose: Health-related quality of life (HRQOL) after prostate brachytherapy has been extensively described in published reports but hardly any long-term data are available. The aim of the present study was to prospectively assess long-term HRQOL 6 years after 125I prostate brachytherapy. Methods and Materials: A total of 127 patients treated with 125I brachytherapy for early-stage prostate cancer between December 2000 and June 2003 completed a HRQOL questionnaire at five time-points: before treatment and 1 month, 6 months, 1 year, and 6 years after treatment. The questionnaire included the RAND-36 generic health survey, the cancer-specific European Organization for Research and Treatment of Cancer core questionnaire (EORTCQLQ-C30), and the tumor-specific EORTC prostate cancer module (EORTC-PR25). A change in a score of ≥10 points was considered clinically relevant. Results: Overall, the HRQOL at 6 years after 125I prostate brachytherapy did not significantly differ from baseline. Although a statistically significant deterioration in HRQOL at 6 years was seen for urinary symptoms, bowel symptoms, pain, physical functioning, and sexual activity (p 125I prostate brachytherapy. HRQOL scores returned to approximately baseline values at 1 year and remained stable up to 6 years after treatment. 125I prostate brachytherapy did not adversely affect patients' long-term HRQOL.

  6. Effects of whole-body irradiation on the degradation of 125I insulin and Na131I insulin in rabbits

    The degradation of simultaneously (i.v.) injected Na131I- and 125I-bovine insuline by rabbit blood and the urinary excretion of Na131I- and 125I-containing insulin degradation products have been investigated before and 24 h after 700 R X-ray irradiation. Also, the distribution of the two substances in the livers, kidneys, spleens, and KI-blocked thyroids was observed after irradiation. Radiation effects on the distribution of Na131I- and 125I-insulin on the livers, kidneys, and spleens of rabbits were not observed. On irradiation, there was a significant reduction of diuresis and also of the urinary excretion of 131I and 125I radioactivity. Irradiation had no influence on the distribution of Na131I-and 125I-insulin between plasma and extravascular space. The renal excretion function for water, iodide, and insulin degradation products was clearly impaired after irradiation. The same applies to the insulincatabolism by the degrading organs. The leukocyte count was reduced to about 17% during the first 4 days after irradiation. (orig./MG)

  7. 5-[125I]iodo-2'-deoxyuridine in the radiotherapy of solid CNS tumors in rats

    We have been investigating the therapeutic efficacy of the thymidine analog 5-iodo-2'-deoxyuridine (IUdR) when radiolabeled with the Auger electron emitter 125I in rats bearing intrathecal (i.t.) or intracerebral (i.c.) 9L gliosarcoma solid tumors. [125I]IUdR was infused i.t. (via subarachnoid catheters) or intracerebrally over a 5- or 2-day period; equimolar concentrations of [127I]IUdR were infused into control animals. High-leg paralysis and/or survival were followed over time. The results indicate that compared with [127I]IUdR, rats bearing intrathecal tumors and infused i.t. with [125I]IUdR showed significant prolongation of the onset of medium paralysis (15.2 versus 9 days). Similarly, the median survival of rats bearing intracerebral tumors and infused i.c. with [125I]IUdR was significantly increased (24 versus 17 days). The data substantiate the antineoplastic potential of [125I]IUdR and indicate a promising role for this radiopharmaceutical in the treatment of CNS cancers. (orig.)

  8. Detection of immune complexes in sera of dogs with rheumatic and neoplastic diseases by 125I-Clq binding test

    Some canine rheumatic and neoplastic diseases bear a striking clinical and serological resemblance to their counterparts in man. In the present study, human 125I-Clq was employed in a radioimmunoassay for detection of immune complexes in sera of normal dogs and those with rheumatic and neoplastic diseases. Human 125I-Clq showed binding of 16.7 +- 5.73% in a group of normal dog sera with binding of 32.5 +- 17.3% and 43.0 +- 16.0% in sera of dogs with rheumatic and neoplastic diseases. respectively. Human 125I-Clq bound similar quantities of heat-aggregated canine and human gamma-globulin over a broad range of concentrations and human 125I-Clq binding in canine sera was effectively inhibited by similar quantities of heat aggregated canine and human gamma-globulin. Seven of 12 dogs with elevated levels of Clq binding had active clinical and serological rheumatic disease (SLE or rheumatoid arthritis), while none of 7 dogs with values within the normal range had active clinical disease. All 5 dogs with widespread osteogenic sarcoma and all 4 dogs with high grade adenocarcinoma of the mammary gland had elevated Clq binding values while 2 animals with low grade malignancies without evident metastases did not. Thus, it appears that human 125I-Clq may be employed to assay immune complexes in canine sera and may be a valuable technique for the study of dogs with various rheumatic and neoplastic diseases. (author)

  9. Changes in 125I-insulin binding antibodies in diabetic pregnant women on insulin therapy and hypoglycemia in newborns

    To elucidate whether insulin antibodies in pregnant diabetics are related to changes in insulin requirement during pregnancy, and whether hypoglycemia in newborns of diabetic mothers is influenced by insulin antibodies transferred through the placenta, changes in 125I-insulin percent binding to insulin antibodies were measured at the first, second and third trimesters of pregnancy and at delivery, in 20 deliveries by 17 diabetics treated with insulin. The free insulin levels in the same serum were also measured for each patient in whom the 125I-insulin binding was decreased more than 5% in the third trimester. The mean percent of 125I-insulin binding in the 20 diabetic pregnancies was unchanged in the first (21.2%) and second trimester (21.1%), but tended to decrease to 17.6% in the third trimester and to increase to 24.6% after delivery. The 125I-insulin percent binding of 5 patients with neonatal hypoglycemia was significantly higher than that of the other patients without hypoglycemia (p125I-insulin percent binding was decreased in the third trimester in contrast with an increased insulin dosage. The finding that hypoglycemia tended to occur in the newborns of diabetic mothers with high insulin percent binding to insulin antibody during the third trimester, suggests that maternal insulin antibodies may affect the fetal pancreas. (author)

  10. Complications after cardiac implantable electronic device implantations

    Kirkfeldt, Rikke Esberg; Johansen, Jens Brock; Nohr, Ellen Aagaard;

    2013-01-01

    Complications after cardiac implantable electronic device (CIED) treatment, including permanent pacemakers (PMs), cardiac resynchronization therapy devices with defibrillators (CRT-Ds) or without (CRT-Ps), and implantable cardioverter defibrillators (ICDs), are associated with increased patient...

  11. Radioautographic identification of lactogen binding sites in rat median eminence using 125I-human growth hormone

    The binding characteristics of human growth hormone were exploited to identify radioautographically lactogen binding sites in the rat median eminence following systemic injection 125I-human growth hormone bound preferentially to the lateral palisade zone, a region of median eminence rich in dopamine and LHRH. Coinjection of 125I-human growth hormone with an excess of unlabeled human growth hormone or ovine prolactin, but not bovine growth hormone, competitively blocked 125I-human growth hormone binding to the external median eminence. These observations provide direct evidence of recognition sites for lactogenic hormones in a discrete region of the median eminence associated with hypothalamic regulation of hypophyseal prolactin and luteinizing hormone secretion. Median eminence lactogen binding sites may mediate presumed direct effects of lactogenic hormones on the reproductive functions of the hypophysiotropic hypothalamus. (orig.)

  12. Can we compare the effect of incorporated 125I with that of a high LET track segment?

    The radioactive isotope 125I decays with a half-life of 60 days via electron capture followed by internal conversion. Both of these processes originate by producing an inner shell vacancy and the atom de-excites by the emission of Auger electrons. After a brief review of the dosimetry of 125I incorporated into the DNA, the probability of depositing an energy E per unit dose in two targets is derived. The result is compared with the same calculation for several alpha particles. It is shown that for small targets the iodine decay electrons are more effective but for the larger targets alpha particles can deposit greater amounts of energy. While high linear energy transfer (LET) like effects have been extensively described for incorporated 125I, a low LET effect reported by previous authors must also be considered. (author)

  13. 111In-platelet and 125I-fibrinogen deposition in the lungs in experimental acute pancreatitis

    An experimental model of acute pancreatitis in rats has been used to study intrapulmonary 125I-fibrinogen and 111In-platelet deposition. Pancreatitis caused a significant increase in wet lung weight compared to normal, and this could be abolished by heparin or aspirin pretreatment. 125I-fibrinogen was deposited in the lungs of animals to a significantly greater degree than in controls (P less than 0.01). 125I-fibrinogen deposition was reduced to control levels by pretreatment with aspirin or heparin (P less than 0.05). The uptake of radiolabeled platelets was greater in pancreatitis than in controls (P less than 0.001). Pancreatitis appears to be responsible for platelet entrapment in the lungs. Platelet uptake was reduced by heparin treatment but unaffected by aspirin therapy

  14. 125I Protein A: applications to the quantitative determination of fluid phase and cell-bound IgG

    An improved method for the preparation of 125I-labelled Protein A (125I PA) of high specific and functional activity is described. α25I PA has been used in combination with purified rabbit IgG bound to a solid support to develop a competitive binding assay capable of detecting Protein A or human, rabbit and guinea pig IgG at the nanogram level. An optimal set of assay conditions was established and levels of IgG measured in normal human, rabbit and strain-2 guinea pig serum. 125I PA has also been used to detect IgG anti-Forssman antibody bound to sheep erythrocytes and to line-1 and line-10 tumor cells and as an indirect assay for tumor associated antigen in the ascitic fluid of tumor-bearing guinea pigs

  15. Binding and degradation of /sup 125/I-insulin by renal glomeruli and tubules isolated from rats

    Meezan, E.; Freychet, P.

    1982-04-01

    Isolated rat renal glomeruli and tubules were shown to exhibit specific binding of /sup 125/I-insulin and enzymatic degradation of the hormone. Binding to both renal fractions reached a plateau by 1 h at 22/sup 0/C and increased linearly with increasing protein concentrations. Binding was inhibited in both preparations by insulin and its analogues in the order of relative potency: insulin > despentapeptide insulin > proinsulin, but insulin was ten times more potent in inhibiting /sup 125/I-insulin binding to glomeruli than that to tubules, indicating a different affinity of receptors for the hormone in the two renal fractions (about 17 versus 210 ..mu..g unlabelled insulin/1 inhibiting 50% of the /sup 125/I-insulin binding to glomeruli and tubules, respectively). Bound /sup 125/I-insulin dissociated at a faster rate from tubules than from glomeruli; this release was accelerated by unlabelled insulin in both renal fractions, but to a greater extent in glomeruli than in tubules. Two-thirds of the total bound material released from glomeruli was found to be intact insulin as measured by trichloroacetic acid precipitation, whereas only one-third of the material released from tubules was intact. No direct relationship between binding and degradation of /sup 125/I-insulin in these renal fractions could be demonstrated, however, because of the release of proteolytic enzymes into the incubation medium resulting in almost all degradation being extracellular. Although differing in their affinity for /sup 125/I-insulin the high affinity glomerular insulin receptor and the lower affinity tubular insulin receptor have characteristics similar to those of insulin receptors in insulin responsive tissues.

  16. [125I](S)-trans-7-OH-PIPAT: A potential SPECT imaging agent for sigma binding sites

    [125I](S)-trans-7-hydroxy-2-[N-n-propyl-N-(3'-iodo-2'-propenyl)]aminotetralin ([125I](s)-trans-7-OH-PIPAT) has been prepared as an iodinated radioligand for studying the sigma binding site. [125I](s)-trans-7-OH-PIPAT binds to rat cerebellar membranes with a Kd=1.67 ± 0.07 nM and Bmax =240 ± 72 fmol/mg of protein (determined in the presence of 15 nM spiperone). This new ligand appears to bind to only one site with Hill coefficients close to unity. Inhibition constants for competing ligands determined in the cerebellar tissue homogenates (in the presence of 15 nM spiperone) are closely comparable to inhibition constants determined in the whole brain tissue homogenates (in the absence of spiperone). Furthermore, these inhibition constants are consistent with the values reported for typical sigma ligands. In vivo uptake of [125I](S)-trans-7-OH-PIPAT in the rat brain is initially high (2.52% dose/organ at 2 min post i.v. injection) and displays a rapid washout from the brain (0.8% dose/organ at 30 min post i.v. injection). Uptake of [125I](S)-trans-7-OH-PIPAT shows moderate target to non-target ratios of 30 minutes (1.54, 1.66 and 1.92 for cerebellar, hypothalamic and hindbrain uptake over striatal uptake, respectively). Pre-injection with haloperidol reduced these ratios to unity suggesting that the ligand binds specifically to haloperidol-sensitive sites in vivo. The selectivity and affinity of [125I](S)-trans-7-OH-PIPAT suggest that this new iodinated ligand may be useful for in vitro studies of the sigma sites and can be used in vivo as a potential SPECT imaging agent

  17. Dosimetric studies, spectrometric, radiographic, metallographic of a new argentinean seed of 125 I used in brachytherapy

    A new source of 125 I model BraquibacTM has been developed in Argentina for applications in interstitial brachytherapy. The AAPM Task Group 43 (TG-43) recommends that dosimetric characteristics of new sources of brachytherapy of Iodine-125 have been theoretically and experimentally determined before its clinical use. The objectives outlined in this work were the study of the design of the new seed, the calculation of dosimetric parameters and the photons spectra analysis. Its were carried out radiographic and metallographic studies to determine the physical characteristics of the source. For the realization of the dosimetric calculations it was used the Monte Carlo code MCNP5. Values of the radial dose function, g(r), of the constant of dose rate, Λ, of the function of anisotropy of two dimensions, F(r, θ), of the factor and constant of anisotropy its were obtained simulating the source in water according to the recommended methodology in TG-43. The constant of dose rate is similar to 0,880 ± 0,080 c Gy h-1 U-1. The kerma in air rate of reference, SK, was calculated as 1,036 c Gy cm2h-1 mCi-1 simulating the seed in dry air. Its were carried out spectrometric studies using a semiconductor planar detector of HPGe (high purity germanium). Photons spectra showed characteristic x-rays of 125 I with energies of 27,20 keV, 27,47 keV, 31 keV and 31,70 keV gamma photons of 35,5 keV, and x-ray fluorescent coming from the silver nucleus of 22,10 keV, 24,94 keV and 25,45 keV. The angular dependence of the intensity of photons around the seed and in air it was analyzed with the planar detector. This was carried out to study the anisotropy in the photons flow due to variation in the thickness of the titanium wall and of the welding, movements of the silver tube inside the source and deposition of the radioactive material on the silver tube. (Author)

  18. Influence of heparin and thromboplastin in half-life of 125I-protein C in rat blood

    The influence of heparin and thromboplastin on the halflife of 125I-protein C in rat blood was under investigation. The intravenous administration of heparin resulted in the prolongation of t1/2 to 6.5 h, that could be explained by inhibition of thrombin generation. Upon the 40-min infusion of thromboplastin the rate of 125I-protein C decay in blood enhanced. That could be explained by the generation of the endogenous thrombin and participation of thrombomodulin in the protein C activation as well as in the removal of the endogenous thrombin from blood

  19. Interaction of paracetamol and 125I-paracetamol with surface groups of activated carbon. Theoretical and experimental study

    The selection of activated carbon (AC) filters for water decontamination is currently carried out empirically. The low concentrations of drugs in the environment make the radioisotope labeling a valuable tool for physical and chemical studies of the adsorption process. A theoretical study of paracetamol and 125I-paracetamol adsorption onto AC was performed to evaluate the interactions between pollutants and surface groups (SG) of AC. Paracetamol was labeled with 125I and adsorption isotherms were obtained using radioanalytical and spectrophotometric techniques. The radioanalytical method overestimates the paracetamol adsorption. The validity of the chosen approach for qualitative assessment of SG influence over the adsorption process was demonstrated. (author)

  20. Transport of 125I in compacted GMZ bentonite containing Fe-oxides, Fe-minerals or Cu2O

    A systematic investigation of the transport of 125I in compacted GMZ bentonite containing Fe-Oxides, Fe-minerals or Cu2O additive was carried out by through diffusion method. The obtained results indicate that all of the additives have positive effects on retarding the 125I diffusion in compacted GMZ bentonite. Especially for the Cu2O additive, the corresponding effective diffusion coefficient is greatly reduced. It is mainly attributed to the particular interactions between the metal ions introduced by additives and iodide ions. (author)

  1. Apoptosis and p53 are not involved in the anti-tumor efficacy of 125I-labeled monoclonal antibodies targeting the cell membrane

    Introduction: 125I-labeled monoclonal antibodies (125I-mAbs) can efficiently treat small solid tumors. Here, we investigated the role of apoptosis, autophagy and mitotic catastrophe in 125I-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 125I-mAbs, or non-internalizing (cell surface location) anti-CEA 125I-mAbs. For each targeting model we established the relationship between survival and mean nucleus absorbed dose using the MIRD formalism. Results: In both p53−/− and p53+/+ HCT116 cells, anti-CEA 125I-mAbs were more cytotoxic per Gy than anti-HER1 125I-mAbs. Sensitivity to anti-CEA 125I-mAbs was p53-independent, while sensitivity to anti-HER1 125I-mAbs was higher in p53−/− HCT 116 cells, suggesting that they act through different signaling pathways. Apoptosis was only induced in p53+/+ HCT116 cells and could not explain cell membrane radiation sensitivity. Inhibition of autophagy did not modify the cell response to 125I-mAbs. By contrast, mitotic death was similarly induced in both p53−/− and p53+/+ HCT116 cells by the two types of 125I-mAbs. We also showed using medium transfer experiments that γ-H2AX foci were produced in bystander cells. Conclusion: Cell membrane sensitivity to 125I-mAbs is not mediated by apoptosis and is p53-independent. Bystander effects-mediated mitotic death could be involved in the efficacy of 125I-mAbs binding cell surface receptors

  2. Synthesis and in vivo studies of a selective ligand for the dopamine transporter: 3β-(4-[125I]iodophenyl) tropan-2β-carboxylic acid isopropyl ester ([125I]RTI-121)

    A selective ligand for the dopamine transporter 3β-(4-iodophenyl)tropan-2β-carboxylic acid isopropyl ester (RTI-121) has been labeled with iodine-125 by electrophilic radioiododestannylation. The [125I]RTI-121 was obtained in good yield (86 ± 7%, n = 3) with high radiochemical purity (>99%) and specific radioactivity (1210-1950 mCi/μmol). After i.v. administration of [125I]RTI-121 to mice, the rank order of regional brain tissue radioactivity (striatum > olfactory tubercles >> cortex, hippocampus, thalamus, hypothalamus, cerebellum) was consistent with dopamine transporter labeling. Specific in vivo binding in striatum and olfactory tubercles was saturable, and was blocked by the dopamine transporter ligands GBR 12,909 and (±)-nomifensine. By contrast, binding was not reduced by paroxetine, a serotonin transporter inhibitor, or desipramine, a norepinephrine transporter inhibitor. A variety of additional drugs having high affinities for recognition sites other than the neuronal dopamine transporter also had no effect. The [125I]RTI-121 binding in striatum and olfactory tubercles was inhibited by d-amphetamine in dose-dependent fashion. Nonmetabolized radioligand represents 85% of the signal observed in extracts of whole mouse brain. Thus, [125I]RTI-121 is readily prepared, and is a useful tracer for dopamine transporter studies in vivo

  3. Synthesis and in vivo studies of a selective ligand for the dopamine transporter: 3{beta}-(4-[{sup 125}I]iodophenyl) tropan-2{beta}-carboxylic acid isopropyl ester ([{sup 125}I]RTI-121)

    Lever, John R.; Scheffel, Ursula; Stathis, Marigo; Seltzman, Herbert H.; Wyrick, Christopher D.; Abraham, Philip; Parham, Karol; Thomas, Brian F.; Boja, John W.; Kuhar, Michael J.; Carroll, F. Ivy

    1996-04-01

    A selective ligand for the dopamine transporter 3{beta}-(4-iodophenyl)tropan-2{beta}-carboxylic acid isopropyl ester (RTI-121) has been labeled with iodine-125 by electrophilic radioiododestannylation. The [{sup 125}I]RTI-121 was obtained in good yield (86 {+-} 7%, n = 3) with high radiochemical purity (>99%) and specific radioactivity (1210-1950 mCi/{mu}mol). After i.v. administration of [{sup 125}I]RTI-121 to mice, the rank order of regional brain tissue radioactivity (striatum > olfactory tubercles >> cortex, hippocampus, thalamus, hypothalamus, cerebellum) was consistent with dopamine transporter labeling. Specific in vivo binding in striatum and olfactory tubercles was saturable, and was blocked by the dopamine transporter ligands GBR 12,909 and ({+-})-nomifensine. By contrast, binding was not reduced by paroxetine, a serotonin transporter inhibitor, or desipramine, a norepinephrine transporter inhibitor. A variety of additional drugs having high affinities for recognition sites other than the neuronal dopamine transporter also had no effect. The [{sup 125}I]RTI-121 binding in striatum and olfactory tubercles was inhibited by d-amphetamine in dose-dependent fashion. Nonmetabolized radioligand represents 85% of the signal observed in extracts of whole mouse brain. Thus, [{sup 125}I]RTI-121 is readily prepared, and is a useful tracer for dopamine transporter studies in vivo.

  4. Proteins labelling with 125I and experimental determination of their specific activity

    A standardization of the labelling technique of proteins with 125I and the control of the obtained products, principally their specific activities was performed, in order to utilize them correctly in radioimmunoassays. The quantities of chloramine-T and sodium metabisulphite were lowered, with regard to the original method, to 3.6 and 9.6 μg respectively. Under these conditions, optimal yields and radioiodinated proteins with good immunological activities were obtained. It was found that the specific activity calculated, as usual, from the yield obtained by electrophoresis, is higher than the real value. For these reasons the yields and the corresponding specific activities were determined from ascending chromatographies performed with 70 per cent methanol as solvent, during two hours in darkness. The radioimmunoassay displacement curves obtained with proteins labelled which the proposed method and the specific activities of which were calculated from their radiochromatographic patterns, were reproducible and gave a percentage of bound radioiodinated protein in the absence of cold protein of 50 +- 4. (author)

  5. Detection of antibodies to bacterial cell wall peptidoglycan in human sera. [/sup 125/I tracer technique

    Heymer, B.; Schleifer, K.H.; Read, S.; Zabriskie, J.B.; Krause, R.M.

    1976-07-01

    A radioimmunoassay has been developed for the measurement of antibodies to peptidoglycan in human sera including patients with rheumatic feaver and juvenile rheumatoid arthritis. The assay is based on the percentage of binding of the hapten /sup 125/I-L-Ala-..gamma..-D-Glu-L-Lys-D-Ala-D-Ala, the major peptide determinant of peptidoglycan. Because of differences in the avidity of the antibodies in different sera, the amount of antibody was expressed as pentapeptide hapten-binding capacity (pentapeptide-HBC in ng/ml of serum). Fourteen out of 105 normal blood donors had a pentapeptide-HBC value greater than or equal to 75 ng/ml serum. Values in healthy children 5 to 18 years of age were less than or equal to 50 ng/ml. Sixty-eight percent of the individuals with rheumatic fever had values greater than or equal to 75 ng/ml, an indication that streptococcal infections can stimulate an immune response to peptidoglycan. Thirty-five percent of the patients with juvenile rheumatoid arthritis had values greater than or equal to 75 ng/ml. Such a finding points to a possible association between bacterial infections and juvenile rheumatoid arthritis.

  6. A proteomics analysis for certain signature proteins of rabbit lacrimal passages after 125I seeds brachytherapy

    To search for certain signature proteins and the expression profiles in lacrimal passage stenosis, rabbit models of lacrimal passage stenosis were treated by 125I seed brachytherapy. All the signature proteins were separated by two-dimensional electrophoresis, and identified by mass spectrometry. The results show that the up-regulated proteins are peptidyl-prolyl cis-trans isomerase A (PPIase A), and epidermal fatty acid-binding protein (E-FABP), while the down-regulated proteins are myosin light chain 1 (isomer of skeletal muscle), myosin light polypeptide 6 (isomer 1 of smooth muscle and non-muscle), myosin light chain 1 (isomer of slow-twitch muscle A), isomer 2 of ERC protein 2, and α-crystalline family protein. The proteins may play a role in healing the wound and regulating synaptic active zone of neurons due to correlation to cell apoptosis, proliferation and migration of smooth muscle cell. These provide molecular mechanism for preventing stenosis and restenosis of lacrimal passage. (authors)

  7. Simultaneous detection of morphine and barbiturates in urine by radioimmunoassay. [/sup 125/I

    Usategui-Gomez, M.; Heveran, J.E.; Cleeland, R.; McGhee, B.; Telischak, Z.; Awdziej, T.; Grunberg, E.

    1975-09-01

    This report describes a radioimmunoassay for the simultaneous detection of morphine and barbiturates. Morphine and barbiturate antibodies, obtained from goats, were mixed with /sup 125/I-labeled antigens. By adjusting concentrations of the morphine and barbiturate antibodies and radiolabeled antigens, closely superimposed standard curves for the two drugs would be obtained. As a consequence, similar response curves were obtained for urine specimens containing morphine or barbiturates. Although concentrations as low as 25 ..mu..g/liter could be measured, to ensure against false positive reactions the test should be performed at the 100 ..mu..g/liter concentration. Unknown samples positive by the dual assay were confirmed by separately testing the specimens with the individual radioimmunoassay specific for morphine or barbiturate. Equivalency tests of urines positive for morphine, positive for barbiturates, or negative for both demonstrated complete correlation between the single and dual assays. The mixed reagent retained its sensitivity and specificity for at least three months when stored at 4 or 25/sup 0/C. The dual radioimmunoassay is a rapid, simple procedure that can be adapted to automated processes and that is suitable for large- and small-scale screening. (auth)

  8. Altered [125I]epidermal growth factor binding and receptor distribution in psoriasis

    Stimulation of growth and differentiation of human epidermis by epidermal growth factor (EGF) is mediated by its binding to specific receptors. Whether EGF receptors primarily mediate cell division or differentiation in hyperproliferative disease such as psoriasis vulgaris is unclear. To study the pathogenesis of psoriasis, 4-mm2 punch biopsy specimens of normal, uninvolved, and involved psoriatic skin were assayed for EGF receptors by autoradiographic, immunohistochemical, and biochemical methods. Using autoradiographic and immunohistochemical methods, basal keratinocytes were found to contain the greatest number of EGF binding sites and immunoreactive receptors as compared to the upper layers of the epidermis in both normal epidermis and psoriatic skin. No EGF receptor differences between normal and psoriatic epidermis were observed in this layer. In the upper layers of the epidermis, a 2-fold increase in EGF binding capacity was observed in psoriatic skin as compared with normal thin or thick skin. Biochemical methods indicated that [125I]EGF binding was increased in psoriatic epidermis as compared with similar thickness normal epidermis when measured on a protein basis. Epidermal growth factor was shown to increase phosphorylation of the EGF receptor in skin. EGF receptors retained in the nonmitotic stratum spinosum and parakeratotic stratum corneum may reflect the incomplete, abnormal differentiation that occurs in active psoriatic lesions. Alternatively, retained EGF receptors may play a direct role in inhibiting cellular differentiation in the suprabasal layers

  9. Absence of preferential uptake of [125I]iododihydrorhodamine 123 by four human tumor xenografts

    The biodistribution of [125I]iododihydrorhodamine 123 has been studied over a 96-h period in four human tumor xenograft models: HT-29 colon adenocarcinoma, PC-3 prostate carcinoma, HT-1080 fibrosarcoma, and PaCa-2 pancreatic carcinoma. Elimination of radioactivity in the tumor-bearing nude mice was rapid during the first 24 h and slow thereafter. The lack of uptake in the thyroid indicated there was little, if any, deiodination of the molecule. Activity was found mainly in the liver and spleen. Accumulation of radioactivity was low in all four tumors examined. At 4 h postinjection, as well as at 24 and 48 h, however, the total radioactive content in each of the four tumors was directly proportional to the weight of the tumor sample. This correlation was independent of tumor type, route of injection (i.v./i.p.) or dose (1.2-6 microCi/mouse). This was not true for any of the normal tissues, suggesting that this accumulation may be governed by certain intrinsic characteristics of the cancers tested

  10. ( sup 125 I)(+)FISCH: A new CNS D-1 dopamine receptor imaging ligand

    Billings, J.; Kung, M.P.; Chumpradit, S.; Pan, S.; Kung, H.F. (Univ. of Pennsylvania, Philadelphia (USA))

    1989-01-01

    Radiolabeling and in vitro and in vivo evaluation of an iodinated benzazepine: ({sup 125}I)FISCH 7-Chloro-8-hydroxy-1-(4{prime}-iodophenyl)-3-methyl-2,3,4,5-tetrahydro-1H-3-benzazepine, as a potential imaging agent for CNS D-1 dopamine receptors in animals, were investigated. After an iv injection, this benzazepine derivative showed good brain uptake in rats. The striatum/cerebellum ratio was 2.50 at 60 min after the injection. The regional distribution in rat brain, as measured by ex vivo autoradiography, displayed highest uptake in the regions of the striatal complex and the substantia nigra, regions known to have a high concentration of D-1 dopamine receptors. Furthermore, this localized regional cerebral distribution was blocked by pretreatment with SCH-23390, a selective D-1 dopamine receptor antagonist. The in vitro binding affinity of this agent in rat striatum tissue preparation displayed a Kd of 1.43 {plus minus} 0.15 nM. Competition data (in vitro) showed the following rank order of potency: SCH-23390 > ({plus minus})IBZP >> apomorphine > WB 4101 > ketanserin {approximately} spiperone. The preliminary data suggest that this analog of SCH-23390 shows similar selectivity for the CNS D-1 receptor.

  11. Determination of dosimetric parameters for 125I seed source using MCNP5 and EGSnrc MC codes

    Background: Seed source has become a popular treatment option in the management of various tumors, particularly in the prostate. Purpose: The aim is to develop accurate and reliable dosimetric parameters that could be used to measure the dose delivered to organs at risk. Methods: Dosimetric parameters (dose rate constant, radial dose function and anisotropy function) of model 6711 125I seed source were calculated with MCNP5 and EGSnrc MC codes following AAPM TG43U1 recommendations. Results: The two results were compared with the relative data recommend by AAPM TG43U1, and the data were as follows: dose rate constant with MCNP5 was in agreement with 0.62%, while that with EGSnrc was 2.07%; radial dose function with MCNP5 was within 0.15%-5.12%, while that with EGSnrc was within 0%-2.48%. Conclusion: The results of two MC codes are in accordance with the recommendations. But that with EGSnrc MC code is better. (authors)

  12. /sup 125/I-radioimmunoassay for unconjugated estroil in serum of pregnant women

    Liedtke, R.J.; Greaves, J.P. Jr.; Batjer, J.D.; Busby, B.

    1978-07-01

    An /sup 125/I-radioimmunoassay is described which measures unconjugated estriol in the serum of pregnant women. Estriol is extracted into ethyl acetate/hexane, an aliquot is evaporated, and the residue is redissolved in phosphate buffer. The sample is incubated with tracer and antibody at 37/sup 0/C for 15 min and then at 4/sup 0/C for 1 h and 45 min. The antibody-bound fraction is then precipitated with polyethylene glycol and isolated by centrifugation. Because the antigen-antibody complex is stable in the presence of polyethylene glycol, the separation steps are not influenced by timing. Extraction recovery of /sup 3/H-labeled estriol added to a pool of sera from pregnant women averaged 96.7% (SD = 1.3, n = 10). Estriol-supplemented (5, 10, and 20 ..mu..g/liter) serum from men, carried through the entire procedure, showed analytical recovery ranging from 94 to 106%. Structurally analogous steroids normally present in serum of pregnant women exhibit negligible cross reactivity. Day-to-day precision (CV) is 13.3% (3.1 ..mu..g/liter), 6.4% (7.6 ..mu..g/liter), and 5.6% (21.4 ..mu..g/liter) for n = 21. The current reagent cost (about 17 cents per tube), and a total procedural time, including counting, of 5.5 h make this an acceptable assay for routine use.

  13. 125I-radioimmunoassay for unconjugated estroil in serum of pregnant women

    An 125I-radioimmunoassay is described which measures unconjugated estriol in the serum of pregnant women. Estriol is extracted into ethyl acetate/hexane, an aliquot is evaporated, and the residue is redissolved in phosphate buffer. The sample is incubated with tracer and antibody at 370C for 15 min and then at 40C for 1 h and 45 min. The antibody-bound fraction is then precipitated with polyethylene glycol and isolated by centrifugation. Because the antigen-antibody complex is stable in the presence of polyethylene glycol, the separation steps are not influenced by timing. Extraction recovery of 3H-labeled estriol added to a pool of sera from pregnant women averaged 96.7% (SD = 1.3, n = 10). Estriol-supplemented (5, 10, and 20 μg/liter) serum from men, carried through the entire procedure, showed analytical recovery ranging from 94 to 106%. Structurally analogous steroids normally present in serum of pregnant women exhibit negligible cross reactivity. Day-to-day precision (CV) is 13.3% (3.1 μg/liter), 6.4% (7.6 μg/liter), and 5.6% (21.4 μg/liter) for n = 21. The current reagent cost (about 17 cents per tube), and a total procedural time, including counting, of 5.5 h make this an acceptable assay for routine use

  14. Monitoring intervals for measurement of the radionuclides 125 I and 129I in thyroid glands

    This work shows the monitoring interval, which can be implemented in the Laboratorio de Contaminacion Interna del Centro de Proteccion e Higiene de las Radiaciones, for direct measurement in the thyroid gland of radionuclides 125I and 129I . Were used two measuring systems, one employing a scintillating detector and the other detector Phoswich. Both detectors were placed inside a depth camera, 2.5 x 2.5 x 2.5m of dimension covered with 15 cm of steel, 3 mm lead, 1.8 mm tin and 1.5 mm of copper. Was calculated for each system, the minimum detectable activity, and based on this, the monitoring interval is determined. Was obtained, for 125, all tested intervals, 120, 90,60,30 , 14, and 7 days may be implemented with both systems. In the case of the radionuclide 129 I, with the installation of scintillating detector can only be implemented the intervals 120, 90, and 60 days , and for installation with Phoswich, all evaluated

  15. Synthesis, in vitro pharmacologic characterization, and preclinical evaluation of N-[2-(1'-piperidinyl)ethyl]-3-[{sup 125}I]iodo-4-methoxybenzamide (P[{sup 125}I]MBA) for imaging breast cancer

    John, Christy S. E-mail: radcsj@gwumc.edu; Bowen, Wayne D.; Fisher, Susan J.; Lim, Benjamin B.; Geyer, Brian C.; Vilner, Bertold J.; Wahl, Richard L

    1999-05-01

    The goal of this study was to investigate the potential use of a radioiodinated benzamide, N-[2-(1'-piperidinyl)ethyl]-3-iodo[{sup 125}I]-4-methoxybenzamide (P[{sup 125}I]MBA), a sigma receptor binding radioligand for imaging breast cancer. The chemical and radiochemical syntheses of PIMBA are described. The pharmacological evaluation of PIMBA was carried out for sigma-1 and sigma-2 receptor sites. The in vivo pharmacokinetics of the radioiodinated benzamide were determined in rats and comparison of P[{sup 125}I]MBA with Tc-99m sestamibi were made in a rat mammary tumor model. Sigma-1 affinity (K{sub i}) for PIMBA in guinea pig brain membranes using [{sup 3}H](+)pentazocine was found to be 11.82{+-}0.68 nM, whereas sigma-2 affinity in rat liver using [{sup 3}H]DTG (1,3-o-di-tolylguanidine) was 206{+-}11 nM. Sites in guinea pig brain membranes labeled by P[{sup 125}I]MBA showed high affinity for haloperidol, (+)-pentazocine, BD1008, and PIMBA (K{sub i}=4.87{+-}1.49,8.81{+-}1.97,0.057{+-}0.005,46.9{+-}1.8 nM), respectively). Competition binding studies were carried out in human ductal breast carcinoma cells (T47D). A dose-dependent inhibition of specific binding was observed with several sigma ligands. K{sub i} values for the inhibition of P[{sup 125}I]MBA binding in T47D cells for haloperidol, N-[2-(1'-piperidinyl)]ethyl]4-iodobenzamide (IPAB), N-(N-benzylpiperidin-4-yl)-4-iodobenzamide (4-IBP), and PIMBA were found to be 1.30{+-}0.07, 13{+-}1.5, 5.19{+-}2.3, 1.06{+-}0.5 nM, respectively. The in vitro binding data in guinea pig brain membranes and breast cancer cells confirmed binding to sigma sites. The saturation binding of P[{sup 125}I]MBA in T47D cells as studied by Scatchard analysis showed saturable binding, with a K{sub d}=94{+-}7 nM and a B{sub max}=2035{+-}305 fmol/mg of proteins. Biodistribution studies in Sprague-Dawley rats showed a rapid clearance of P[{sup 125}I]MBA from the normal organs. The potential of PIMBA in imaging breast cancer was

  16. Iodine-125 thin seeds decrease prostate swelling during transperineal interstitial permanent prostate brachytherapy

    Prostate swelling following seed implantation is a well-recognised phenomenon. The purpose of this intervention was to assess whether using thinner seeds reduces post-implant swelling with permanent prostate brachytherapy. Eighteen consecutive patients eligible for prostate seed brachytherapy underwent seed implantation using iodine-125 (I-125) thin seeds. Operative time, dosimetry, prostate swelling and toxicity were assessed and compared with standard I-125 stranded seed controls, sourced from the department's brachytherapy database. A learning curve was noted with the thin seeds in terms of greater bending and deviation of needles from their intended path. This translated into significantly longer total operative time (88 vs 103 minutes; P=0.009, 95% confidence interval (CI) 4.1-24.3) and time per needle insertion (2.6 vs 3.7 minutes; P<0.001, 95% CI 0.5-1.3) for the thin seeds. Day 30 prostate volumes were significantly smaller in the thin seed group compared with standard seeds (40.9cc vs 46.8cc; P=0.001, 95% CI 1.5-5.6). The ratio of preoperative transrectal ultrasound to day 30 post-implant CT volume was also smaller in the thin seed group (1.2±0.1 for standard seeds vs 1.1±0.1 for thin seeds). Post-implant dosimetric parameters were comparable for both groups. No significant differences were seen in acute urinary morbidity or quality of life between the two groups. I-125 thin seeds are associated with an initial learning curve, with longer operative time, even for experienced brachytherapists. The significant reduction in day 30 prostate volumes with the thin seeds has useful implications in terms of optimising dose coverage to the prostate in the early period post-implantation, as well as improving the accuracy of post-implant dosimetric assessments.

  17. Radiosynthesis and in vivo evaluation of [125I]2-(4-iodophenethyl)-2-methylmalonic acid as a potential radiotracer for detection of apoptosis

    The aim of this study is to synthesize 125I-labeled 2-(4-iodophenethyl)-2-methylmalonic acid ([125I]IMA) for the development of new apoptosis imaging tracer. The optimized radiolabeling procedure provided [125I]IMA with high radiochemical yield (75.5 ± 5.2 %) and radiochemical purity ([99 %) within 100 min. Specific radioactivity of [125I]IMA was 31.0 MBq/lmol. Biodistribution study of [125I]IMA was carried out using ICR mouse and the result showed the uptake values in apoptotic cells of the testes of the male mice were 1.7-3.2 fold higher than those of leg muscle. Therefore, [125I]IMA will be a promising radiotracer for in vivo SPECT imaging of apoptotic cells. (author)

  18. Characterization of [125I]omega-conotoxin binding to brain N calcium channels and (-)[3H] desmethoxyverapamil binding to novel calcium channels in osteoblast-like osteosarcoma cells

    This dissertation provides molecular evidence for a diversity of Ca2+ channels in neuronal and non-neuronal tissues. First, I demonstrated specific, reversible, saturable binding sites for omega [125I]conotoxin GVIA (omega[125I]CTX) in rat brain and rabbit sympathetic ganglion. Omega [125I]CTX binding has a unique pharmacology, ion selectivity, and anatomical distribution in rat brain. Omega [125I]CTX binding was solubilized, retaining an appropriate pharmacology and ion selectivity. Omega[125I]CTX binding may be associated with a Ca2+ channel because the K/sub D/ of omega [125I]CTX is similar to the IC50 of inhibition of depolarization-induced 45Ca2+ flux into rat brain synaptosomes. Specific (-)[3H]desmethoxyverapamil ((-)[3H]DMV) binding sites were demonstrated on osteoblast-like osteosarcoma cell membranes

  19. The characters of 125I-VIP binding to the receptors derived from human gastrointestinal adenocarcinoma and their adjacent tissues

    To investigate the characteristics of 125I-VIP binding to human gastrointestinal adenocarcinoma and their adjacent tissue. VIP was labelled with Na 125I using chloramine -T method, separated by Sephadex G-50 column chromatography and examined by silica 60F254 thin layer chromatography. The effects of time and temperature on the specific binding were examined, saturable binding and competitive binding between 125I-VIP and VIP receptors in membranes from gastrointestinal adenocarcinoma and their adjacent tissue were carried out. The results showed that labelling rate was 70%, the specific activity of 125I-VIP was 18TBq/mmol, the radiochemical purity was better than 98%. A single specific binding sites of high affinity were present in gastric adenocarcinoma and its adjacent tissue as well as in colon adenocarcinoma and its adjacent tissue. The Kd and Bmax values were 1.19 nmol/L and 339 fmol/mg protein, 1.26 nmol/L and 156 fmol/mg protein, 0.97 nmol/L and 304 fmol/mg protein, 1.53 nmol/L and 151 fmol/mg protein respectively. The present study demonstrated that the binding sites of VIP on human gastrointestinal adenocarcinoma were more abundant than their adjacent tissue membrane, which provide valuable experimental evidence for VIP receptor imaging

  20. Radiosynthesis and in vivo evaluation of the pseudopeptide {delta}-opioid antagonist [{sup 125}I]-ITIPP({psi})

    Collier, T.L. E-mail: TC311@columbia.edu; Schiller, P.W.; Waterhouse, R.N

    2001-05-01

    The radioiodinated tetrapeptide {delta}-opioid antagonist [{sup 125}I]ITIPP({psi}) [H-Tyr(3'I)-Tic{psi}[CH{sub 2}NH]Phe-Phe-OH] (Ki({delta}) 2.08 nM; Ki({mu})/Ki({delta}) = 1280) has been synthesized and evaluated as a potential lung tumour imaging agent. [{sup 125}I]ITIPP({psi}) was obtained, via electrophilic iodination, in 46% yield (>44,000 MBq/{mu}mol) from the parent TIPP({psi}). The biodistribution of [{sup 125}I]ITIPP({psi}) in nu/nu mice bearing SCLC-SW210.5 xenographs revealed good uptake and prolonged retention of radioactivity in organs known to possess {delta}-opioid receptors. Metabolite analysis showed that [{sup 125}I]ITIPP({psi}) was largely unmetabolized at 25 min PI and blocking studies showed significant reduction of uptake of the tracer in the brain, liver, intestine and tumor indicating that the iodinated tetrapeptide binds to {delta} opioid receptors in vivo.

  1. Cellular receptor for 125I-labeled tumor necrosis factor: specific binding, affinity labeling, and relationship to sensitivity

    Tumor necrosis factor (TNF) is a proteinaceous toxin shed by stimulated myeloid cells. Murine TNF was radioiodinated to a specific activity of 1 mCi/nmol (1 Ci = 37 GBq) of monomer. 125I-labeled TNF (125-TNF) retained complete cytotoxic activity and it was immunochemically identical to the native toxin in a quantitative immunoprecipitation assay. It could be shown by competition binding that 125I-TNF bound to intact L929 cells with a specificity equal to that of native toxin. The conditions of time, temperature, and concentration involved in equilibrium specific binding to intact cells were studied in detail. J774.1 cells, the source of the toxin, demonstrated similar binding but were not sensitive to 125I-TNF cytotoxicity. Normal lymphoid organ cell suspensions and two human tumorigenic cell lines were not sensitive and failed to demonstrate specific binding. 125I-TNF, covalently cross-linked to its receptor on sensitive L-M cells with disuccinimidyl suberate, was isolated and analyzed by sodium dodecyl sulfate/polyacrylamide gel electrophoresis and autoradiography. Two specific bands were identified. The presence of the binding site appears to be necessary but not sufficient to explain the sensitivity of cells to the cytotoxic action of TNF

  2. Experimental study of triplex-forming oligonucleotide targeted to the initiator of S gene of HBV labeled with 125I

    This study is used to investigate the feasibility of employing the Iodogen method to label triplex-forming oligonucleofide (TFO) targeted to the initiator of the S gene of HBV with 125I. A 17-mer oligonucleotides sequence was synthesized and grafted at the 5' terminal with a tyramine group. Radioiodination of the tyramine-TFO with 125I was then performed using the Iodogen method. After TFO was labeled with 125I using the Iodogen method, the labeling rate, the radiochemical purity, stability and bioactivity were determined, respectively. The results show that the radiolabeling rate and the radiochemical purity were 93% and 99%, respectively; and the radiochemical purity is more than 90% in vitro at -20 degree C on the 5th day after labeling; and the rate of 125I-tyramine-TFO binding to HepG2.2.15 cells was (37.2 ± 1.4)% and statistically different from the rate of HepG2 (p<0.5). Hence, it is concluded that the labeling of oligonucleotides conjugated with tyramine using the Iodogen method is successful and is characterized with a high labeling rate, high stability, and a low loss of bioactivity of the labeled agent. (authors)

  3. 125I-albumin may not be used as a tracer of absorption across the human nasal airway bassiers

    This study set out to examine the effects of histamine on airway absorption of macromolecules. By employment of a novel 'nasal pool' technique instillates containing 125I-albumin with or without histamine, were kept for 15 min on human nasal mucosa. Unaffected by the presence of histamine, this instillations produced significant levels of plasma radioactivity, increasing for 60 min. However, gel-filtration data showed that only 30% of the plasma radioactivity was still bound to albumin. Incubation experiments indicated that radioiodine did not dissociate from albumin in nasal liquids nor in the blood. Further experiments involved oral ingestion of the entire nasal instillate. Prompts gastrointestinal absorption of radioactivity occurred, giving rise to plasma levels about two orders of magnitude higher than those recorded after the nasal applications. Moreover, only 25% of the plasma radioactivity was now bound to albumin. It must be considered unavoidable that a small portion (125I-albumin and subsequent absorption of radioiodine. We conclude that 125I-albumin may not be employed in studies addressing macromolecular absorption across the human nasal mucosa and that previous work and conclusions based on nasal absorption of 125I-albumin are invalid. (au)

  4. Acute changes in intra-alveolar tooth position and local clearance of 125I from the periodontal ligament

    Changes in intra-alveolar tooth position and local 125I clearance from the periodontal ligament (PDL) were monitored simultaneously in cats. Axial tooth movements, reflecting periodontal ligament volume changes, were measured with an ultrasonic transit time technique. Local blood flow changes in the PDL were studied indirectly by measuring the local clearance of 125I. Stimulation of the cervical sympathetic trunk caused an intrusive movement of the tooth with a concomitant reduction of the 125I-clearance. Infusion of noradrenaline induced a similar respone. Stimulation of the inferior alveolar nerve during systemic treatment with phentolamine caused an extrusive movement of the tooth with a concomitant increase in the clearance of the tracer from the PDL. Intra-arterial infusion of the vasodilator substance P mimicked that response. Fization of the tooth to the jaw bone, thus preventing an intrusive movement, did not change the reductions in clearance seen on sympathetic stimulation, indicating that this blood flow reduction was not dependent on tooth movement. A qualitative relation between PDL blood flow (as measured by local 125I clearance) and PDL volume (as measured by tooth position) in shown. The two variables measured are suggested to reflect two aspects of blood flow in the PDL

  5. Culture conditions affecting the incorporation of 125I-labelled iododeoxyuridine into DNA of mitogen-stimulated canine lymphocytes

    A series of experiments have been conducted to define and describe the response of canine lymphocytes in the mitogen stimulation assay systems. These studies include the effects of serum, mitogen, and FUDR concentrations on the incorporation of 125I-IUDR by canine lymphocytes

  6. Solid-phase immunoassay for human immunoglobulin E: use of 125I-labeled protein A as a tracer

    A solid-phase immunoassay has been developed for human immunoglobulin (Ig) E. The specific binding of 125I-labeled protein A (125I-PA) to the Fc region of rabbit IgG anti-IgE served as a quantitative measure of specific anti-IgE antibody bound to the IgE beads under optimal assay conditions. Inhibition of antibody binding by known amounts of standard IgE was reflected in a decreased binding of 125I-PA. The degree of inhibition of 125I-PA binding was related to the amount of fluid-phase IgE present and gave a standard curve which was used to determine the concentration of IgE in test samples. The sensitivity of this method and a double antibody radioimmunoassay (RIA), which was developed using the same IgE preparation and anti-IgE antibody, was approximately the same. These assays gave similar results when used to determine levels of IgE in normal human sera that had been absorbed with protein A-Sepharose to remove components responsible for specific and nonspecific interference in the assays

  7. 125I-labelled tetanus toxin as a neuronal marker in tissue cultures derived from embryonic CNS

    Primary cultures derived from embryonic mouse brain and spinal cord were exposed to 125I-labelled tetanus toxin and subjected to autoradioraphy. Cells with neuronal, bur not glial, morphology selectively accumulated the toxin. The distribution of the grains over these cells and their processes was not uniform, discrete processes showing heavier labelling. (orig.)

  8. Pharmacokinetics, tissue distribution and excretion of a recombinant fusion protein 125I-rhTNT-IL2

    This study examined the tissues distribution and pharmacokinetics of rhTNT-IL2, a fusion protein, in rats and macaques after iv. injection. The rhTNTIL2 was labeled with 125I. The 125I-rhTNT-IL2 was administered into rats and macaques at a dose of 250 μg x kg-1 and 125 μg x kg-1, respectively. Upon administration, rhTNT-IL2 declined in tri-exponentially with the half-lives of 1.78 h (T1/2α), 25.06 h (T1/2β), 114.19 h (T1/2γ) for rats and 1.87 h (T1/2α), 9.82 h (T1/2β), 43.17 h (T1/2γ) for macaques. The fraction of 125I-rhTNT-IL2 excreted in feces was low (about 1%), while the majority of 125I-rhTN-IL2 was excreted in urine. The tissue distributions showed that the liver, spleen and heart were major organs for deposition of the fusion protein in rats and macaques in 48-hour post-injection, and the fusion protein could not penetrate through blood brain barrier. (author)

  9. Microdosimetric spread for cell-sized targets exposed to 60Co, 192Ir and 125I sources

    The magnitude of the spread in specific energy deposition per cell may be a confounding factor in dose- response analysis motivating derivation of explicit data for the most common brachytherapy isotopes 125I and 192Ir, and for 60Co radiation frequently used as reference in RBE studies. The aim of this study is to analyse the microdosimetric spread as given by the frequency distribution of specific energy for a range of doses imparted by 125I, 192Ir and 60Co sources. An upgraded version of the Monte Carlo code PENELOPE was used for scoring energy deposition distributions in liquid water for each of the radiation qualities. Frequency distributions of specific energy were calculated according to the formalism of Kellerer and Chmelevsky. Results indicate that the magnitude of the microdosimetric spread increases with decreasing target size and decreasing energy of the radiation quality. Within the clinical relevant dose range (1 to 100 Gy), the spread does not exceed 4 % for 60Co, 5 % for 192Ir and 6 % for 125I. The frequency distributions can be accurately approximated with symmetrical normal distributions at doses down to 0.2 Gy for 60Co, 0.1 Gy for 192Ir and 0.08 Gy for 125I. (authors)

  10. Extraction of 129I and 127I via combustion from organic rich samples using 125I as a quantitative tracer

    Iodine-129 (129I) is a biophilic, naturally occurring radioisotope (half-life: 1.57 × 107 years) that has been released in large quantities by nuclear fuel reprocessing. This iodine has cycled throughout the globe and chiefly the northern hemisphere and can be found in a wide variety of environmental materials, particularly organic rich soil and organic matter. Extracting iodine reliably from solid samples has been done by a variety of methods, however, pyrohydrolysis has been the most widely used. There is a wide variation between existing pyrohydrolysis techniques and this raises questions about the quantitative recovery of iodine from method to method. In order to quantify iodine recovery from pyrohydrolysis we have spiked samples with an iodine-125 radiotracer prior to combustion and trapping in an alkaline solution. Inorganic 125I tracer was used as well as humic acid labeled with 125I to simulate the behavior of 129I and 127I in complex organic substances and extract iodine regardless of how it is partitioned. Using these tracers we explored the effect on recovery of 125I under a variety of combustion parameters. These include carrier gas flow rate and iodine volatilization temperature. We observed that the best recoveries of 125I were at flow rates between 400 and 800 mL/min and most 125I recoveries were above 85%. The experiment to determine the temperature at which iodine volatilizes from the sample showed two distinct trends for the release of iodine. One trend showed that most iodine is released at approximately 525 °C, while the other trend showed that the samples needed to reach 800 °C and remain there for at least an hour. These findings illustrate the usefulness and importance of using a quantitative recovery tracer for every iodine extraction. We then combusted and precipitated several Atlantic Ocean seaweed and standard reference materials for AMS analysis as AgI. The 129I concentration of the seaweed ranged between 4.4–5.5 × 109 atoms/g and

  11. Quantitative autoradiography of 125I-[Sar1, Ile8]-angiotensin II binding in the brain of spontaneously hypertensive rats

    The brain contains its own angiotensin II (AII) system. To better understand the role of central AII in cardiovascular regulation, we used 125I-[Sar1, Ile8]-AII (125I-SI-AII), radioactive AII antagonist, to autoradiographically localize putative AII receptor binding in many parts of the central nervous system of the spontaneously hypertensive (SHR) and normotensive Wistar-Kyoto (WKY) rats. With 125I-SI-AII binding on brain membrane preparations. Scatchard analysis indicated that Kd values were from 0.10 +/- 0.04 nM to 0.13 +/- 0.05 nM, whereas Bmax values (femtomol/mg protein) were found to be from 6.95 +/- 1.60 to 15.52 +/- 4.99 among brain regions studied. Various SI-AII receptor binding activities among brain regions revealed in this study were therefore most likely due to differences in AII receptor density with high affinity binding of 125I-AII. Using 125I-SI-AII, specific binding for SI-AII was found in the nucleus tractus solitarius (NTS), paraventricular hypothalamic nucleus (PVN), subfornical organ (SFO), suprachiasmatic nucleus (SCN), area postrema, the dorsal motor nucleus of the vagus (DMX), and the nucleus of spinal tract of the trigeminal system (NSV). With quantitative receptor autoradiography in conjunction with radioactive standards, we have observed that the NTS possesses the highest SI-AII binding, followed by the PVN, SFO, NTS, DMX, and NSV. No significant differences were observed between the SHR and WKY rats in the SI-AII binding within the SFO, PVN and NTS. However, SHR at early hypertensive (7 weeks) and established hypertensive (16 weeks) stages contained significantly higher SI-AII bindings in the NSV, as compared to age-matched WKY rats

  12. 2-(/sup 125/I)iodomelatonin binding sites in hamster brain membranes: pharmacological characteristics and regional distribution

    Duncan, M.J.; Takahashi, J.S.; Dubocovich, M.L.

    1988-05-01

    Studies in a variety of seasonally breeding mammals have shown that melatonin mediates photoperiodic effects on reproduction. Relatively little is known, however, about the site(s) or mechanisms of action of this hormone for inducing reproductive effects. Although binding sites for (3H)melatonin have been reported previously in bovine, rat, and hamster brain, the pharmacological selectivity of these sites was never demonstrated. In the present study, we have characterized binding sites for a new radioligand, 2-(125I)iodomelatonin, in brains from a photoperiodic species, the Syrian hamster. 2-(125I)Iodomelatonin labels a high affinity binding site in hamster brain membranes. Specific binding of 2-(125I)iodomelatonin is rapid, stable, saturable, and reversible. Saturation studies demonstrated that 2-(125I)iodomelatonin binds to a single class of sites with an affinity constant (Kd) of 3.3 +/- 0.5 nM and a total binding capacity (Bmax) of 110.2 +/- 13.4 fmol/mg protein (n = 4). The Kd value determined from kinetic analysis (3.1 +/- 0.9 nM; n = 5) was very similar to that obtained from saturation experiments. Competition experiments showed that the relative order of potency of a variety of indoles for inhibition of 2-(125I)iodomelatonin binding site to hamster brain membranes was as follows: 6-chloromelatonin greater than or equal to 2-iodomelatonin greater than N-acetylserotonin greater than or equal to 6-methoxymelatonin greater than or equal to melatonin greater than 6-hydroxymelatonin greater than or equal to 6,7-dichloro-2-methylmelatonin greater than 5-methoxytryptophol greater than 5-methoxytryptamine greater than or equal to 5-methoxy-N,N-dimethyltryptamine greater than N-acetyltryptamine greater than serotonin greater than 5-methoxyindole (inactive).

  13. 2-[125I]iodomelatonin binding sites in hamster brain membranes: pharmacological characteristics and regional distribution

    Studies in a variety of seasonally breeding mammals have shown that melatonin mediates photoperiodic effects on reproduction. Relatively little is known, however, about the site(s) or mechanisms of action of this hormone for inducing reproductive effects. Although binding sites for [3H]melatonin have been reported previously in bovine, rat, and hamster brain, the pharmacological selectivity of these sites was never demonstrated. In the present study, we have characterized binding sites for a new radioligand, 2-[125I]iodomelatonin, in brains from a photoperiodic species, the Syrian hamster. 2-[125I]Iodomelatonin labels a high affinity binding site in hamster brain membranes. Specific binding of 2-[125I]iodomelatonin is rapid, stable, saturable, and reversible. Saturation studies demonstrated that 2-[125I]iodomelatonin binds to a single class of sites with an affinity constant (Kd) of 3.3 +/- 0.5 nM and a total binding capacity (Bmax) of 110.2 +/- 13.4 fmol/mg protein (n = 4). The Kd value determined from kinetic analysis (3.1 +/- 0.9 nM; n = 5) was very similar to that obtained from saturation experiments. Competition experiments showed that the relative order of potency of a variety of indoles for inhibition of 2-[125I]iodomelatonin binding site to hamster brain membranes was as follows: 6-chloromelatonin greater than or equal to 2-iodomelatonin greater than N-acetylserotonin greater than or equal to 6-methoxymelatonin greater than or equal to melatonin greater than 6-hydroxymelatonin greater than or equal to 6,7-dichloro-2-methylmelatonin greater than 5-methoxytryptophol greater than 5-methoxytryptamine greater than or equal to 5-methoxy-N,N-dimethyltryptamine greater than N-acetyltryptamine greater than serotonin greater than 5-methoxyindole (inactive)

  14. Ocular brachytherapy dosimetry for 103Pd and 125I in the presence of gold nanoparticles: a Monte Carlo study.

    Asadi, Somayeh; Vaez-Zadeh, Mehdi; Vahidian, Mohammad; Marghchouei, Mahdieh; Masoudi, S Farhad

    2016-01-01

    The aim of the present Monte Carlo study is to evaluate the variation of energy deposition in healthy tissues in the human eye which is irradiated by brachytherapy sources in comparison with the resultant dose increase in the gold nanoparticle (GNP)-loaded choroidal melanoma. The effects of these nanoparticles on normal tissues are compared between 103Pd and 125I as two ophthalmic brachytherapy sources. Dose distribution in the tumor and healthy tissues has been taken into account for both brachytherapy sources. Also, in certain points of the eye, the ratio of the absorbed dose by the normal tissue in the presence of GNPs to the absorbed dose by the same point in the absence of GNPs has been calculated. In addition, differences of the absorbed dose in the tumor observed in the comparison of simple water phantom and actual simulated human eye in presence of GNPs are also a matter of interest that have been considered in the present work. The difference between the eye globe and the water phantom is more obvious for 125I than that of the 103Pd when the ophthalmic dosimetry is done in the presence of GNPs. Whenever these nanoparticles are utilized in enhancing the absorbed dose by the tumor, the use of 125I brachytherapy source will greatly amplify the amount of dose enhancement factor (DEF) in the tumor site without inflicting much dam-age to healthy organs, when compared to the 103Pd source. For instance, in the concentration of 30 mg GNPs, the difference amongst the calculated DEF for 125I between these phantoms is 5.3%, while it is 2.45% for 103Pd. Furthermore, in Monte Carlo studies of eye brachytherapy, more precise definition of the eye phantom instead of a water phantom will become increasingly important when we use 125I as opposed to 103Pd. PMID:27167265

  15. Minocycline treatment attenuates non-Ang II[125I] CGP42112 binding in brainstem following nodose ganglionectomy

    Full text: Non-Ang II [125I]CGP42112 binding was revealed in rat dorsal motor nucleus (DMX), ambiguus nucleus (n.amb), and nucleus of the solitary tract (NTS), following unilateral nodose ganglionectomy (NGX). This upregulated binding may be due to activated microglia. Given that tetracyclines inhibit microglia activation, we examined the effect of minocycline treatment on [125I]CGP42112 and [3H] PK11195 binding (a know marker for activated microglia), following NGX using autoradiography. Male Wistar Kyoto (WKY)rats underwent NGX or sham operation (mexohexitione anaesthesia, 60mg/kg ip). Animals were given saline or minocycline (50 mg/kg ip)12 hours before surgery and twice daily after NGX (each 100mg/kg ip)for 3 days. Slide-mounted brainstem sections (14 μm) were prepared and incubated in the presence of either [125I]CGP42112 (0.3nM) or [3H]PK11195 (3nM) and apposed to film for 10 days. Specific binding was determined in adjacent sections co- incubated with unlabelled displacers. Non-Ang II [125I]CGP42112 binding in DMX and n.amb was revealed on the denervated side in saline-treated rats (n=4), whereas this effect was reduced by ∼41 % and ∼ 54%, respectively, in minocycline-treated rats (n=4). Analogous experiments using [3H] PK11195 showed upregulated binding on the denervated side in DMX (44 ± 4 %) and in n.amb (68 ± 3 %) of saline-treated rats (n=4), which was reduced by ∼ 45% with minocyline treatment in both nuclei (n=4). Minocycline also attenuated NGX-induced upregulated binding to both ligands in the NTS. Thus, these data suggest that non-Ang II[125I]CGP42112 binds to activated microglia, indicated by reduced binding densities following treatment with minocycline. Copyright (2001) Australian Neuroscience Society

  16. Quantitative pharmacological analysis of 2-125I-iodomelatonin binding sites in discrete areas of the chicken brain

    The authors have localized and characterized 2-125I-iodomelatonin binding sites in the chicken brain using in vitro quantitative autoradiography. Binding sites were widely distributed throughout the chicken brain, predominantly in regions associated with the visual system. The specific binding of 2-125I-iodomelatonin to discrete chicken brain areas was found to be saturable, reversible, and of high affinity. The specific binding of 2-125I-iodomelatonin (75 pm) was quantitated for 40 identifiable brain regions. Eight brain regions were chosen for binding characterization and pharmacological analysis: optic tectum, Edinger-Westphal nucleus, oculomotor nucleus, nucleus rotundus, ventral supraoptic decussation, ventrolateral geniculate nucleus, neostriatum, and ectostriatum. These regions showed no rostral-caudal gradient in 2-125I-iodomelatonin specific binding, and saturation analysis revealed a single class of high-affinity sites with KD values in the range of 33-48 pM and receptor site density (Bmax) ranging from 31 to 58 fmol/mg protein. Competition experiments carried out with various indoles revealed a similar order of pharmacological affinities in these areas: melatonin greater than 6-chloromelatonin greater than methoxyluzindole greater than N-acetylserotonin greater than luzindole much greater than 5-HT greater than 5-methoxytryptamine. The affinity constants determined by quantitative autoradiography for these compounds to compete for 2-125I-iodomelatonin binding in the optic tectum correlated well with the affinities in chicken brain membranes at 25 degrees C (r = 0.966; slope = 0.845; n = 7) and 0 degree C (r = 0.946; slope = 0.379; n = 7), chicken retinal membranes (r = 0.973; slope = 0.759; n = 7), and the potency or affinity of these compounds to affect the calcium-dependent release of 3H-dopamine from the rabbit retina (r = 0.902; slope = 0.506; n = 6)

  17. Alternative labelling of the cocaine analogue isomers α-CIT and β-CIT by direct iodination with no-carrier-added Na125I

    An alternative labelling of the cocaine analogue isomers α-CIT and β-CIT with no-carrier-added 125I by direct iodination of 2α- and 2β-carbomethoxy-3β-phenyltropane with Na125I/sulfuric acid/nitric acid/acetic acid and peracetic acid under different reaction conditions, is described. The maximum radiolabelling yield obtained with the two isomers was 48% for [125I]α-CIT and 28% for [125I]β-CIT. (author)

  18. Suppression of 125I-uptake in mouse thyroid by seaweed feeding

    We conducted an animal experiment to determine how dietary seaweeds rich in iodine and dietary fibers suppress radioactive iodine uptake by the thyroid, using mice and four kinds of experimental diets, three with 1% or 2% powdered fronds of the kelp Laminaria religiosa and 2% powdered laver Porphyra yezoensis, and one with cellulose. Iodine content of a hot-water extract of the kelp was 0.530±0.001%, and its dietary fiber (DF) values were 52.8±1.2%. Iodine in an extract of the laver was 0.008±0.001%, and its DF values were 41.4%±0.7%. A statistically significant reduction of 125I uptake by the thyroid, 3 hours after intragastric administration of the radionuclide at a dosage of 18.5 kBq or 185 kBq in 0.3 ml aqueous solution per mouse, was observed in mice previously fed the experimental diets containing 1% and 2% kelp during periods varying from 24 hours to 7 days. The degree of the suppression was observed to depend on the amount of iodine in the diet or in the injected sample, no matter whether organic or inorganic, judging from the results of an additional experiment. Thus, we conclude that previously fed iodine-rich material, especially dietary seaweeds rich in iodine and other minerals, vitamins, and β-carotene, such as kelps or laver supplemented with inorganic iodine, may be effective in prevention of internal radiation injury of the thyroid. (author)

  19. Synthesis, in vitro binding, and tissue distribution of radioiodinated 2-[{sup 125}I]N-(N-benzylpiperidin-4-yl)-2-iodo benzamide, 2-[{sup 125}I]BP: a potential {sigma} receptor marker for human prostate tumors

    John, Christy S.; Gulden, Mary E.; Li, Jinghua; Bowen, Wayne D.; McAfee, John G.; Thakur, Mathew L

    1998-04-01

    The preclinical evaluation of a {sigma} receptor-specific radiopharmaceutical that binds to human prostate tumor cells with a high affinity is described. We have synthesized and radioiodinated 2-[{sup 125}I]-N-(N-benzylpiperidin-4-yl)-2-iodobenzamide (2-[{sup 125}I]BP) that possesses high affinity for both {sigma}-1 and {sigma}-2 receptor subtypes that are expressed on a variety of tumor cells. 2-IBP was synthesized, purified and characterized by routine spectroscopic and analytical methods. Radioiodination was accomplished using an oxidative iododestannylation reaction in the presence of chloramine T in high yields (76%-93%) with a very high-specific activity (1700-1900 Ci/mmol). The in vitro competition binding studies of 2-[{sup 125}I]BP with various {sigma} receptor ligands in LnCAP human prostate tumor cells showed a dose-dependent saturable binding. The inhibition constants (K{sub i}, nM) for binding of 2-[{sup 125}I]BP to human prostate tumor cells for 4-IBP, haloperidol and 2-IBP were 4.09, 6.34 and 1.6 nM, respectively. The clearance of 2-[{sup 125}I]BP, in Sprague-Dawley rats, was rapid from the blood pool, other normal tissues and the total body. Tissue distribution studies in nude mice bearing human prostate tumor (DU-145) also showed a fast clearance from normal organs. The tumor had the highest percentage of injected dose per gram (%ID/g) of all tissues at 4 h as well as 24 h (2.0 {+-} 0.05 and 0.147 {+-} 0.038 ID/g, respectively) postinjection. The in vivo receptor binding specificity was demonstrated using haloperidol (a known high-affinity {sigma} receptor ligand). A significant decrease (>50%, p = 0.001) was observed in tumor concentration when haloperidol was used as a blocking agent. The high affinity of 2-[{sup 125}I]BP for {sigma} receptor-binding sites, its fast in vivo clearance from normal organs and its high uptake and retention in tumor implies that 2-[{sup 123}I]BP or 2-[{sup 131}I]BP may be a promising tracer for noninvasive imaging of

  20. Synthesis, in vitro binding, and tissue distribution of radioiodinated 2-[125I]N-(N-benzylpiperidin-4-yl)-2-iodo benzamide, 2-[125I]BP: a potential σ receptor marker for human prostate tumors

    The preclinical evaluation of a σ receptor-specific radiopharmaceutical that binds to human prostate tumor cells with a high affinity is described. We have synthesized and radioiodinated 2-[125I]-N-(N-benzylpiperidin-4-yl)-2-iodobenzamide (2-[125I]BP) that possesses high affinity for both σ-1 and σ-2 receptor subtypes that are expressed on a variety of tumor cells. 2-IBP was synthesized, purified and characterized by routine spectroscopic and analytical methods. Radioiodination was accomplished using an oxidative iododestannylation reaction in the presence of chloramine T in high yields (76%-93%) with a very high-specific activity (1700-1900 Ci/mmol). The in vitro competition binding studies of 2-[125I]BP with various σ receptor ligands in LnCAP human prostate tumor cells showed a dose-dependent saturable binding. The inhibition constants (Ki, nM) for binding of 2-[125I]BP to human prostate tumor cells for 4-IBP, haloperidol and 2-IBP were 4.09, 6.34 and 1.6 nM, respectively. The clearance of 2-[125I]BP, in Sprague-Dawley rats, was rapid from the blood pool, other normal tissues and the total body. Tissue distribution studies in nude mice bearing human prostate tumor (DU-145) also showed a fast clearance from normal organs. The tumor had the highest percentage of injected dose per gram (%ID/g) of all tissues at 4 h as well as 24 h (2.0 ± 0.05 and 0.147 ± 0.038 ID/g, respectively) postinjection. The in vivo receptor binding specificity was demonstrated using haloperidol (a known high-affinity σ receptor ligand). A significant decrease (>50%, p = 0.001) was observed in tumor concentration when haloperidol was used as a blocking agent. The high affinity of 2-[125I]BP for σ receptor-binding sites, its fast in vivo clearance from normal organs and its high uptake and retention in tumor implies that 2-[123I]BP or 2-[131I]BP may be a promising tracer for noninvasive imaging of human prostate tumors

  1. Low elastic modulus Ti–Ta alloys for load-bearing permanent implants: Enhancing the biodegradation resistance by electrochemical surface engineering

    Kesteven, Jazmin [Biomaterials and Engineering Materials (BEM) Laboratory, School of Engineering and Physical Sciences, James Cook University, Townsville, Queensland 4811 (Australia); Kannan, M. Bobby, E-mail: bobby.mathan@jcu.edu.au [Biomaterials and Engineering Materials (BEM) Laboratory, School of Engineering and Physical Sciences, James Cook University, Townsville, Queensland 4811 (Australia); Walter, Rhys; Khakbaz, Hadis [Biomaterials and Engineering Materials (BEM) Laboratory, School of Engineering and Physical Sciences, James Cook University, Townsville, Queensland 4811 (Australia); Choe, Han-Choel [Department of Dental Materials, Chosun University, Gwangju 501-759 (Korea, Republic of)

    2015-01-01

    In this study, the in vitro degradation behaviour of titanium–tantalum (Ti–Ta) alloys (10–30 wt.% Ta) was investigated and compared with conventional implant materials, i.e., commercially pure titanium (Cp-Ti) and titanium–aluminium–vanadium (Ti6Al4V) alloy. Among the three Ti–Ta alloys studied, the Ti20Ta (6.3 × 10{sup −4} mm/y) exhibited the lowest degradation rate, followed by Ti30Ta (1.2 × 10{sup −3} mm/y) and Ti10Ta (1.4 × 10{sup −3} mm/y). All the Ti–Ta alloys exhibited lower degradation rate than that of Cp-Ti (1.8 × 10{sup −3} mm/y), which suggests that Ta addition to Ti is beneficial. As compared to Ti6Al4V alloy (8.1 × 10{sup −4} mm/y), the degradation rate of Ti20Ta alloy was lower by ∼ 22%. However, the Ti30Ta alloy, which has closer elastic modulus to that of natural bone, showed ∼ 48% higher degradation rate than that of Ti6Al4V alloy. Hence, to improve the degradation performance of Ti30Ta alloy, an intermediate thin porous layer was formed electrochemically on the alloy followed by calcium phosphate (CaP) electrodeposition. The coated Ti30Ta alloy (3.8 × 10{sup −3} mm/y) showed ∼ 53% lower degradation rate than that of Ti6Al4V alloy. Thus, the study suggests that CaP coated Ti30Ta alloy can be a viable material for load-bearing permanent implants. - Highlights: • In vitro degradation of titanium–tantalum (Ti–Ta) alloys was studied. • Ta addition to Ti is beneficial for better degradation resistance. • Ti–Ta alloys perform better than commercially pure Ti. • Calcium phosphate coated Ti–Ta alloy is superior to Ti6Al4V alloy.

  2. Low elastic modulus Ti–Ta alloys for load-bearing permanent implants: Enhancing the biodegradation resistance by electrochemical surface engineering

    In this study, the in vitro degradation behaviour of titanium–tantalum (Ti–Ta) alloys (10–30 wt.% Ta) was investigated and compared with conventional implant materials, i.e., commercially pure titanium (Cp-Ti) and titanium–aluminium–vanadium (Ti6Al4V) alloy. Among the three Ti–Ta alloys studied, the Ti20Ta (6.3 × 10−4 mm/y) exhibited the lowest degradation rate, followed by Ti30Ta (1.2 × 10−3 mm/y) and Ti10Ta (1.4 × 10−3 mm/y). All the Ti–Ta alloys exhibited lower degradation rate than that of Cp-Ti (1.8 × 10−3 mm/y), which suggests that Ta addition to Ti is beneficial. As compared to Ti6Al4V alloy (8.1 × 10−4 mm/y), the degradation rate of Ti20Ta alloy was lower by ∼ 22%. However, the Ti30Ta alloy, which has closer elastic modulus to that of natural bone, showed ∼ 48% higher degradation rate than that of Ti6Al4V alloy. Hence, to improve the degradation performance of Ti30Ta alloy, an intermediate thin porous layer was formed electrochemically on the alloy followed by calcium phosphate (CaP) electrodeposition. The coated Ti30Ta alloy (3.8 × 10−3 mm/y) showed ∼ 53% lower degradation rate than that of Ti6Al4V alloy. Thus, the study suggests that CaP coated Ti30Ta alloy can be a viable material for load-bearing permanent implants. - Highlights: • In vitro degradation of titanium–tantalum (Ti–Ta) alloys was studied. • Ta addition to Ti is beneficial for better degradation resistance. • Ti–Ta alloys perform better than commercially pure Ti. • Calcium phosphate coated Ti–Ta alloy is superior to Ti6Al4V alloy

  3. Dose Escalation to the Dominant Intraprostatic Lesion Defined by Sextant Biopsy in a Permanent Prostate I-125 Implant: A Prospective Comparative Toxicity Analysis

    Purpose: Using real-time intraoperative inverse-planned permanent seed prostate implant (RTIOP/PSI), multiple core biopsy maps, and three-dimensional ultrasound guidance, we planned a boost volume (BV) within the prostate to which hyperdosage was delivered selectively. The aim of this study was to investigate the potential negative effects of such a procedure. Methods and Materials: Patients treated with RTIOP/PSI for localized prostate cancer with topographic biopsy results received an intraprostatic boost (boost group [BG]). They were compared with patients treated with a standard plan (reference group [RG]). Plans were generated using a simulated annealing inverse planning algorithm. Prospectively recorded urinary, rectal, and sexual toxicities and dosimetric parameters were compared between groups. Results: The study included 120 patients treated with boost technique who were compared with 70 patients treated with a standard plan. Boost technique did not significantly change the number of seeds (55.1/RG vs. 53.6/BG). The intraoperative prostate V150 was slightly higher in BG (75.2/RG vs. 77.2/BG, p = 0.039). Urethra V100, urethra D90, and rectal D50 were significantly lower in the BG. No significant differences were seen in acute or late urinary, rectal, or sexual toxicities. Conclusions: Because there were no differences between the groups in acute and late toxicities, we believe that BV can be planned and delivered to the dominant intraprostatic lesion without increasing toxicity. It is too soon to say whether a boost technique will ultimately increase local control.

  4. Clinical outcome of intermediate risk prostate cancer treated with iodine 125 mono-therapy: The Hotel-Dieu of Quebec experience;Evolution clinique des patients atteints d'un cancer prostatique de risque intermediaire traites par implants permanents d'iode-125: l'experience de l'Hotel-Dieu de Quebec

    Zebentout, O.; Apardian, R.; Beaulieu, L.; Harel, F.; Martin, A.G.; Vigneault, E. [Departement de radiotherapie, CHUQ Hotel-Dieu, QC (Canada); Beaulieu, L.; Harel, F. [Centre de recherche en cancerologie, CHUQ Hotel-Dieu, universite de Laval, QC (Canada); Beaulieu, L. [Departement de physique, de genie physique et d' optique, universite de Laval, QC (Canada)

    2010-06-15

    Purpose To describe the biochemical failure-free survival (B.F.F.S.), G.U. toxicity and erectile dysfunction in intermediate risk prostate cancer treated with iodine 125 mono-therapy ({sup 125}I). Patients and methods Between October 1994 and October 2007, 1282 patients were treated with {sup 125}I at the Hotel Dieu de Quebec. Two hundred patients were intermediate risk prostate cancer. One hundred and fifty-seven had enough follow-up to be evaluated in this study. Biochemical failure-free survival is reported using Phoenix definition. Acute and late G.U. toxicity was described using the International Prostate Symptoms Score (I.P.S.S.) as well as with the rate of bladder catheter. Erectile dysfunction was also reported. Results The mean age of the patients was 65.6 years (S.D. = 6 years) and the mean pretreatment P.S.A. was 8.7 ng/ml. About half of the patients (51%) were T2b/T2c. About 44.6% had a P.S.A. greater than 10 and 4.5% had Gleason score of 7/10. More than half of the patients received a short course of hormones of less than 6 months for cyto-reduction (57.4%). The median follow-up was 60 months. Biochemical failure-free survival at 60-month and 96-month were 87.1% and 81% according to Phoenix definition. The mean I.P.S.S. rose from 5 immediately after the implant to 15 1 month after and then slowly decreased to 8 at 24 months. Acute urinary retention with bladder catheter occurred in 10.9% of patients. Only 4.3% presented erectile dysfunction at 5 months post-implant. Conclusion {sup 125}I mono-therapy for intermediate risk prostate implant gives biochemical failure-free survivals at 5 years and 8 years comparable to those obtained with high dose external beam radiotherapy. G.U. toxicity and erectile dysfunction were low and acceptable. Therefore, the use of {sup 125}I alone in this group of patients could be presented and discussed with the patient in the waiting of phase III validation. (authors)

  5. 125I seed for the treatment of late cancer of the liver

    Objectives: To investigate whether iodine-125 radioactive seed can be used for the treatment of late cancer of the liver. Methods: Ten patients with unresectable (primary or metastatic) cancer of the liver were studied. Nine patients were male and 1 was female. The mean age was 61+/-14 years old. Five of the patients had primary liver of the cancer. Before treatment was initiated, informed consents were collected. The iodine-125 radioactive seeds were provided by the China Academy of Atomic Energy. The radioactivity of each seed was 0.8 mCi The num.ber of seeds to be implanted was estimated according to the size of the tumor measured through CT scan. On the day of the operation, the patients we to the department of radiology and a CT scan performed and the location and angle of puncture evaluated by the radiologist, Then needles for delivering the seeds were inserted into the tumor through the skin. While the tip of the needles was at the desired location, the seeds were implanted into the tumor. In some cases, bleeding occurred, but this did not stop the implantation. After the and their successfully completed, a CT scan was performed to confirm the number of seeds implanted and their distribution. One month after the implantation, the patients were reevaluated with CT scan to investigate whether the tumor had shrunk or not. The patients were followed up for 6 months. Results: Of the ten patients, 1 committed suicide because of severe bone pain caused by bone metastasis. Another patient died of other cause other than cancer itself. All the other patients were alive at 6 month after the operation and CT scan was performed. All tumor of the nine patients shrunk significantly. Conclusion: Iodine-125 brachytherapy is effective for the treatment of late cancer of the liver. (authors)

  6. Feasibility of MR Imaging/MR Spectroscopy-Planned Focal Partial Salvage Permanent Prostate Implant (PPI) for Localized Recurrence After Initial PPI for Prostate Cancer

    Hsu, Charles C., E-mail: hsucc@radonc.ucsf.edu [Department of Radiation Oncology, University of California, San Francisco Helen Diller Family Comprehensive Cancer Center, San Francisco, California (United States); Hsu, Howard [Department of Radiation Oncology, New York University, New York, New York (United States); Pickett, Barby [Department of Radiation Oncology, University of California, San Francisco Helen Diller Family Comprehensive Cancer Center, San Francisco, California (United States); Crehange, Gilles [Department of Radiation Oncology, Dijon University, Dijon (France); Hsu, I-Chow Joe; Dea, Ryan [Department of Radiation Oncology, University of California, San Francisco Helen Diller Family Comprehensive Cancer Center, San Francisco, California (United States); Weinberg, Vivian [Biostatistics and Computational Biology Core, University of California, San Francisco Helen Diller Family Comprehensive Cancer Center, San Francisco, California (United States); Gottschalk, Alexander R. [Department of Radiation Oncology, University of California, San Francisco Helen Diller Family Comprehensive Cancer Center, San Francisco, California (United States); Kurhanewicz, John [Department of Radiology, University of California, San Francisco Helen Diller Family Comprehensive Cancer Center, San Francisco, California (United States); Shinohara, Katsuto [Department of Urology, University of California, San Francisco Helen Diller Family Comprehensive Cancer Center, San Francisco, California (United States); Roach, Mack [Department of Radiation Oncology, University of California, San Francisco Helen Diller Family Comprehensive Cancer Center, San Francisco, California (United States)

    2013-02-01

    Purpose: To assess the feasibility of magnetic resonance imaging (MRI)-planned partial salvage permanent prostate implant (psPPI) among patients with biopsy-proven local recurrence after initial PPI without evidence of distant disease. Methods and Materials: From 2003-2009, 15 patients underwent MRI/magnetic resonance spectroscopy (MRS) planning for salvage brachytherapy (psPPI, I-125 [n=14; 144 Gy]; Pd-103 [n=1; 125 Gy]) without hormone therapy. Full dose was prescribed to areas of recurrence and underdosage, without entire prostate implantation. Limiting urethral and rectal toxicity was prioritized. Follow-up was from salvage date to prostate-specific antigen (PSA) concentration failure (Phoenix criteria = nadir + 2.0; ASTRO = 3 consecutive rises), recurrence, distant metastases, or last follow-up PSA level. Progression-free survival (PFS) was defined as no PSA failure or biopsy-proven recurrence without all-cause mortality. Toxicity was scored using Common Terminology Criteria for Adverse Events version 4.0. Results: At salvage, median age was 68 years, and PSA concentration was 3.5 ng/mL (range, 0.9-5.6 ng/mL). Abnormal MRI/MRS findings were evident in 40% of patients. Biopsy-proven recurrences consisted of a single focus (80%) or 2 foci (20%). At recurrence, Gleason score was 6 (67%) or {>=}7 (27%). Median interval between initial and salvage implantation was 69 months (range, 28-132 months). psPPI planning characteristics limited doses to the rectum (mean V100 = 0.5% [0.07 cc]) and urethra (V100 = 12% [0.3 cc]). At median follow-up (23.3 months; range, 8-88 months), treatment failure (n=2) resulted only in localized recurrence; both patients underwent second psPPI with follow-up PSA tests at 12 and 26 months, resulting in 0.6 and 0.7 ng/mL, respectively. American Society for Radiation Oncology PFS rates at 1, 2, and 3 years were 86.7%, 78.4%, and 62.7%, respectively, with 5 patients for whom treatment failed (n=3 with negative transrectal ultrasound

  7. Feasibility of MR Imaging/MR Spectroscopy-Planned Focal Partial Salvage Permanent Prostate Implant (PPI) for Localized Recurrence After Initial PPI for Prostate Cancer

    Purpose: To assess the feasibility of magnetic resonance imaging (MRI)-planned partial salvage permanent prostate implant (psPPI) among patients with biopsy-proven local recurrence after initial PPI without evidence of distant disease. Methods and Materials: From 2003-2009, 15 patients underwent MRI/magnetic resonance spectroscopy (MRS) planning for salvage brachytherapy (psPPI, I-125 [n=14; 144 Gy]; Pd-103 [n=1; 125 Gy]) without hormone therapy. Full dose was prescribed to areas of recurrence and underdosage, without entire prostate implantation. Limiting urethral and rectal toxicity was prioritized. Follow-up was from salvage date to prostate-specific antigen (PSA) concentration failure (Phoenix criteria = nadir + 2.0; ASTRO = 3 consecutive rises), recurrence, distant metastases, or last follow-up PSA level. Progression-free survival (PFS) was defined as no PSA failure or biopsy-proven recurrence without all-cause mortality. Toxicity was scored using Common Terminology Criteria for Adverse Events version 4.0. Results: At salvage, median age was 68 years, and PSA concentration was 3.5 ng/mL (range, 0.9-5.6 ng/mL). Abnormal MRI/MRS findings were evident in 40% of patients. Biopsy-proven recurrences consisted of a single focus (80%) or 2 foci (20%). At recurrence, Gleason score was 6 (67%) or ≥7 (27%). Median interval between initial and salvage implantation was 69 months (range, 28-132 months). psPPI planning characteristics limited doses to the rectum (mean V100 = 0.5% [0.07 cc]) and urethra (V100 = 12% [0.3 cc]). At median follow-up (23.3 months; range, 8-88 months), treatment failure (n=2) resulted only in localized recurrence; both patients underwent second psPPI with follow-up PSA tests at 12 and 26 months, resulting in 0.6 and 0.7 ng/mL, respectively. American Society for Radiation Oncology PFS rates at 1, 2, and 3 years were 86.7%, 78.4%, and 62.7%, respectively, with 5 patients for whom treatment failed (n=3 with negative transrectal ultrasound

  8. Evaluation of the Coat-A-Count 125I fentanyl RIA: Comparison of 125I RIA and GC/MS-SIM for quantification of fentanyl in case urine specimens

    The Coat-A-Count solid phase 125I Fentanyl Radioimmunoassay was evaluated with respect to linearity and precision using equine urine fortified with fentanyl and then compared with a gas chromatographic/mass spectrometric method for quantification of fentanyl in urine. The RIA assay was found to be linear over the urine fentanyl concentration range of 0.25 to 7.5 ng/mL and precise with coefficients of variation (CV) ranging from 9.6 to 19.3%. The RIA calibrators, ranging in fentanyl concentrations from 0.25 to 7.5 ng/mL, and controls, at mean fentanyl concentrations of 0.46 and 1.32 ng/mL, were compared by both the RIA and GC/MS methods. The cross-reactivity with the 125I RIA test was determined for the fentanyl metabolites, norfentanyl and hydroxyfentanyl, and found to be 5% and 35%, respectively. The illicit fentanyl analogs were found to show significant cross-reactivity, ranging from 20 to 100%. The 125I RIA was compared to GC/MS quantifications of fentanyl in 35 positive and 20 negative case urine specimens

  9. Solid-phase radioimmunoassay for IgG gliadin antibodies using /sup 125/I-labelled staphylococcal protein A

    Troncone, R.; Pignata, C.; Farris, E.; Ciccimarra, F. (Naples Univ. (Italy). II Facolta di Medicina)

    1983-10-14

    A sensitive radioimmunoassay for IgG gliadin antibodies is described. Serum specimens were added to wells of plastic microtitre plates coated with gliadin. After removal of the unbound material, gliadin antibodies were detected by adding /sup 125/I-labelled staphylococcal protein A (/sup 125/I-SpA). Serum specimens from coeliac patients on a normal diet or on a gluten-free diet were tested, as well as sera from an age-matched control group. Measurements to obtain precise quantitative values were made with gliadin antibody-rich serum as reference standard. High titres of gliadin antibodies were found in 18 out of 19 coeliac patients on a normal diet (95%); in patients on a strict gluten-free diet serum values did not exceed 2 S.D. of the control mean. Due to the high sensitivity of the method a low but detectable amount of gliadin antibody was present in the sera of all controls.

  10. A solid-phase radioimmunoassay for IgG gliadin antibodies using 125I-labelled staphylococcal protein A

    A sensitive radioimmunoassay for IgG gliadin antibodies is described. Serum specimens were added to wells of plastic microtitre plates coated with gliadin. After removal of the unbound material, gliadin antibodies were detected by adding 125I-labelled staphylococcal protein A (125I-SpA). Serum specimens from coeliac patients on a normal diet or on a gluten-free diet were tested, as well as sera from an age-matched control group. Measurements to obtain precise quantitative values were made with gliadin antibody-rich serum as reference standard. High titres of gliadin antibodies were found in 18 out of 19 coeliac patients on a normal diet (95%); in patients on a strict gluten-free diet serum values did not exceed 2 S.D. of the control mean. Due to the high sensitivity of the method a low but detectable amount of gliadin antibody was present in the sera of all controls. (Auth.)

  11. Investigation on the in vivo σ peceptor locating roperty of 125I-4-(N-benzylpiperidin)-4-iodo-phenylsulfonamide

    Tributylstannane precursor of the ligand is synthesized, characterized and labeled with 125I by oxidative radioiododestannylation methods. To investigate the a receptor affinity and the suitability for tumor guiding diagnosis and guiding therapy of 125I-4-(N-benzylpiperidin)-4-iodo- phenylsulfonamide in vivo, 443 kBq/(0.2 μg) of the labeled ligand is injected into mice bearing H22, S180 and EAC tumor, respectively, and their biodistribution is measured. The results show that high uptake is obtained in liver, spleen, heart, lung, kidney, small intestine in which σ receptors are present as well as in H22 and EAC tumor. In the blocking study using haloperidol, coinjection with haloperidol reduced the uptake in heart, lung and spleen but no inhibition is showed in tumor. The higher T/NT values of tumor to brain and muscle are obtained, 6.98 at 2 hours postinjection of tumor to muscle is the highest. (authors)

  12. 3H and 125I radioimmunoassays of haloperidol compared with fluoroimmunoassay involving antibody coupled to magnetizable solid phase

    Radioimmunoassays for haloperidol are described, involving use of tritium-or 125I-labeled drug or tritium-labeled spiroperidol, and a rabbit antiserum to a drug/bovine serum albumin conjugate. The 125I-labeled drug was prepared by the Chloramine T iodination technique. A fluoroimmunoassay for haloperidol is also described in which the antiserum is coupled to magnetizable solid-phase medium, and fluorescein-labeled haloperidol is used. The assays have acceptable accuracy, precision, and reproducibility, and are specific for haloperidol and similar butyrophenones, with no significant interference from known metabolites and other drugs. Only the radioimmunoassays have sufficient sensitivity to cover the whole range of haloperidol concentrations in serum. The fluoroimmunoassay can be used to monitor high concentrations of haloperidol in 150 μL samples or the complete concentration range of 1-mL serum samples that are extracted and concentrated before assay

  13. 3H and 125I radioimmunoassays of haloperidol compared with fluoroimmunoassay involving antibody coupled to magnetizable solid phase

    Radioimmunoassays for haloperidol are described, involving use of tritium- or 125I-labeled drug or tritium-labeled spiroperidol, and a rabbit antiserum to a drug/bovine serum albumin conjugate. The 125I-labeled drug was prepared by the Chloramine T iodination technique. A fluoroimmunoassay for haloperidol is also described in which the antiserum is coupled to magnetizable solid-phase medium, and fluorescein-labeled haloperidol is used. The assays have acceptable accuracy, precision, and reproducibility, and are specific for haloperidol and similar butyrophenones, with no significant interference from known metabolites and other drugs. Only the radioimmunoassays have sufficient sensitivity to cover the whole range of haloperidol concentrations in serum. The fluoroimmunoassay can be used to monitor high concentrations of haloperidol in 150-microL samples or the complete concentration range of 1-mL serum samples that are extracted and concentrated before assay

  14. Synthesis and characterization of [{sup 125}I]N-(2-aminoethyl)-4-iodobenzamide as a selective monoamine oxidase B inhibitor

    Rafii, Hamid; Chalon, Sylvie; Ombetta, Jean-Edouard; Frangin, Yves; Garreau, Lucette; Dognon, Anne-Marie; Lena, Isabelle; Bodard, Sylvie; Vilar, Marie-Paule; Besnard, Jean-Claude; Guilloteau, Denis

    1995-07-01

    We described the radiosynthesis of an analog of Ro 16-6491, [{sup 125}I]N-(2-aminoethyl)-4-iodobenzamide, for SPECT exploration of the monoamine oxidase B (MAO-B) in human brain. The radiolabelling was carried out by nucleophilic exchange of the brominated precursor at solid-state phase in presence of ammonium sulphate. The radiochemical purity of radioiodinated product was higher than 95%. In comparison with Ro 16-6491, the in vitro studies showed a good selectivity of stable N-(2-aminoethyl)-4-iodobenzamide for MAO-B but a slightly lower affinity. Biodistribution studies in the rat showed a high and selective uptake of this compound in the pineal gland 1 h after i.v. injection. The cerebral uptake was low, but the coupling of [{sup 125}I]N-(2-aminoethyl)-4-iodobenzamide with a lipophilic radical to enhance the passage through the blood-brain barrier can be envisaged.

  15. Use of 125I-iododeoxyuridine uptake in bone marrow and spleen after gamma-irradiation and cystamine radioprotection

    The method of 125I-iododeoxyuridine labelling of hemopoietic cell populations in vivo was used to estimate the effect of peroral cystamine radioprotection (250 mg/kg) on cell proliferation activity in the spleen and femoral bone marrow of mice gamma-irradiated with 0.5, 1 and 2 Gy whole-body doses. The early postirradiation depression of proliferation activity, as observed 4 h after irradiation, was not modified by cystamine protection, only signs of deeper depression were noted. Cystamine radioprotection increases the rate of cell proliferation in the recovery phase, as evidenced 24 h after irradiation. 125I-iododeoxyuridine assays seems to be a suitable method for evaluating effects of even weakly acting radioprotective means in conditions of small dose irradiation. (author)

  16. Specific binding properties of 125I-apamin in various structures of the rat central nervous system.

    Janicki, P K

    1989-01-01

    The properties of 125I-apamin binding with rat central nervous system slices were analysed in vitro using computerized densitometric autoradiography. Scatchard analysis performed for the data of binding experiments in rat brain and spinal cord demonstrates that apamin binds to a single class of non-interacting binding sites in all investigated structures. The dissociation constant values (KD) were similar in all investigated structures (31-38 pM). The maximal binding capacity (Bmax) was observed in the structures of limbic olfactory system (30 fmol/mg protein), the lowest in brain white matter (0.5 fmol/mg protein). It is concluded that the observed pattern of 125I-apamin binding might represent the topography of a class of Ca2+ dependent K+ channels in the rat central nervous system. PMID:2641420

  17. Biodistribution and γ imaging of 125I-labeled goat anti-human IgG polyclonal antibody in nude mice bearing human colon cancer xenografts

    The possibility of IgG secreted from tumor cells as a target for radioimmunoimaging and targeted therapy of cancers were investigated. Goat anti-human IgG polyclonal anti- body (GAHG) was radioiodinated using Iodogen method, and the in vitro stability and pharmacokinetics were evaluated. The biodistribution and γ imaging of 125I-GAHG were performed in nude mice bearing HT-29 human colon cancer xenografts. 125I-GAHG showed good in vitro stability, and its blood clearance was defined as a two-compartment model, with T1/2α and T1/2β were 1.19 h and 43.99 h, respectively. The tumor uptake of 125I-GAHG was higher than that of 125I-labeled normal goat IgG control (125I-GIgG). 125I-GAHG showed good tumor retention when injecting via intra-tumor. In the biodistribution study, the highest tumor uptake of 125I-GAHG was 6.71±2.19%ID/g at 72 h postinjection and the T/NT increased along with the postinjection time. The results show that 125I-GAHG have good tumor-specific uptake which may provide a novel idea for radioimmunoimaging and targeted therapy of cancers. (authors)

  18. Liquid scintillation counting standardization of ''125 I in organic and inorganic samples by the CIEMAT/NIST method

    The liquid scintillation counting standardization of organic and inorganic samples of ''125 I by the CIEMAT/NIST method using five different scintillators is described. The discrepancies between experimental and computed efficiencies are lower than 1.4% and 1.7%, for inorganic and organic samples, respectively, in the interval 421-226 of quenching parameter. Both organic and inorganic solutions have been standardized in terms of activity concentration to an overall uncertainty of 0.76%

  19. Characterization and segmental distribution of 125I-Bolton-Hunter-labeled substance P binding sites in rat spinal cord

    Substance P (SP) is widely distributed in the spinal cord and has been implicated as a neurotransmitter in several spinal cord neuronal systems. To investigate SP receptors in the spinal cord, 125I-Bolton-Hunter-SP (125I-BH-SP) was used to identify and characterize spinal cord binding sites for the peptide. The binding of 125I-BH-SP had the following characteristics: high affinity; time, temperature, and membrane concentration dependent; reversible; and saturable. The IC50 of SP in whole spinal cord was 0.46 nM as compared with 0.95, 60, and 150 nM for physalaemin, eledoisin, and kassinin. Four putative antagonists of SP were less than 0.0001 times as potent as SP in inhibiting 125I-BH-SP binding. IC50s were 5, 7.5, 7.0, and 45 microM for D-Pro2, D-Trp7,9-SP; D-Pro2, D-Phe7, D-Trp9-SP; D-Arg1, D-Pro2, D-Trp7,9, Leu11-SP; and D-Pro4, D-Trp7,9,10-SP(4-11), respectively. The lumbosacral section bound 3 times more SP than the cervical and thoracic sections, although IC50 for the cervical section was 0.06 of that for the lumbosacral and thoracic sections. The data suggest more than one class of binding site for SP in the spinal cord and indicate a direct role for SP in spinal cord functions

  20. The quantitation of biotinylated compounds by a solid-phase assay using a 125I-labelled biotin derivative

    The biotin analogue biotinylglycyltyrosine has been synthesized and labelled to a specific activity of 2000 Ci/mmol with 125I. This analogue has been used in conjunction with immobilized streptavidin in an assay which detects as little as 1 fmol biotin or biotinylated molecules in solution. The determination of biotinylated insulin in a tissue extract and the quantitation of a transcription assay are given as examples. (Auth.)

  1. Conditions for succseful labeling of oxidation sensitive peptides by Na[125-I] - IODO-GEN(TM) system

    Elbert, Tomáš; Veselá, Iva

    2010-01-01

    Roč. 53, 5/6 (2010), s. 288-291. ISSN 0362-4803. [International Symposium on the Synthesis and Applications of Isotopes and Isotopically Labelled Compounds /10./. Chicago, 14.06.2009-18.06.2009] R&D Projects: GA MŠk LA 288 Institutional research plan: CEZ:AV0Z40550506 Keywords : Iodo-Gen * peptide * 125-I * radiolabelling Subject RIV: CC - Organic Chemistry Impact factor: 1.096, year: 2010

  2. Evaluation of new iodinated acridine derivatives for targeted radionuclide therapy of melanoma using 125I, an Auger electron emitter

    The full text of the publication follows. The increasing incidence of melanoma and the lack of effective therapy on the disseminated form have led to an urgent need for new specific therapies. Several iodo-benzamides or analogs are known to possess specific affinity for melanoma tissue. New hetero-aromatic derivatives have been designed with a cytotoxic moiety and termed DNA intercalating agents. These compounds could be applied in targeted radionuclide therapy using 125I, Auger electrons emitter which gives high-energetic localized irradiation. Two iodinated acridine derivatives have been reported to present an in vivo kinetic profile conducive to application in targeted radionuclide therapy. The aim of the present study was to perform a preclinical evaluation of these compounds. The DNA intercalating property was confirmed for both compounds. After radiolabeling with 125I, the two compounds induced in vitro a significant radiotoxicity on B16F0 melanoma cells. The acridine compound, ICF01040, appeared more radio toxic than the acridone compound, ICF01035. While cellular uptake was similar for both compounds, SIMS analysis and in vitro protocol showed a stronger affinity for melanin with ICF01035, which was able to induce a predominant scavenging process in the melanosome and restrict access to the nucleus. Nevertheless, an important radiotoxicity was measured for the two compounds while the nuclear accumulation was low. Indeed, even if nuclear localization remains the main target sensitive to Auger electrons, the cell membrane remains sensitive to 125I decays. So, these compounds may induce secondary toxic effects of irradiation, such as membrane lipid damage. Conducted to current experiments are evaluate such hypothesis. Taken together, these results suggest that ICF01040 is a better candidate for application in targeted radionuclide therapy using 125I. The next step will be in vivo evaluation, where high tumoral vectorization gives promising perspectives

  3. Autoradiographic visualization of A 1-adenosine receptors in brain and peripheral tissues of rat and guinea pig using 125I-HPIA

    A 1-adenosine receptors were identified in sections of rat brain and guinea pig kidney with the radioiodinated agonist 125I-N6-p-hydroxyphenylisopropyladenosine (125I-HPIA) using in vitro autoradiography. The affinities of adenosine receptor ligands in competing with 125I-HPIA binding to tissue sections were in good agreement with those found in membranes and indicate that the binding site represents an A 1 pattern of [3H]N6-cyclohexyladenosine ([3H]CHA) binding sites determined previously, with highest densities in the hippocampus and dentate gyrus, the cerebellar cortex, some thalamic nuclei and certain layers of the cerebral cortex. In the guinea pig kidney 125I-HPIA labelled longitudinal structures in the medulla. This study demonstrates that 125I-HPIA allows the autoradiographic detection of A-1 adenosine receptors in the brain and peripheral organs and has the advantage of short exposure times (author)

  4. Effects of methoxyflurane anesthesia on the pharmacokinetics of 125I-IAZA in sprague-dawley rats

    Effects of methoxyflurane anesthesia on the pharmacokinetics of intravenous 125I-IAZA in rats are reported. No significant differences in t1/2α, t1/2β, Vss, and ClTB for total radioactivity (125I-IAZA and metabolites) were observed between the anesthetized (Group 1, n=4) and nonanesthetized (Group 2, n=3) animals. For 125I-IAZA, ClTB increased from 646±52 mL/h/kg to 2250±351 mL/h/kg and t1/2β decreased from 97.7±17.5 min to 35.6±5.4 min, for Groups 1 and 2, respectively. There were no differences in Vss or t1/2α between the two groups. These findings support literature reports of anesthetic effects on xenobiotic pharmacokinetics, and indicate a need for caution in the evaluation of preclinical imaging studies in which animals are immobilized with anesthetics

  5. DNA breakage, repair and lethality after 125I decay in rec+ and recA strains of Escherichia coli

    Iodine-125 decays by electron capture and is known to cause extensive molecular fragmentation via the Auger effect. 125I was incorporated into the DNA of exponentially-growing E. coli K12 AB2487, a recA mutant, and E. coli K12 AB2497, the corresponding rec+ strain as 5-iododeoxyuridine (IUdR), an analogue of thymidine. Radioactive bacteria were stored at -1960C, and samples were periodically assayed for loss of viability and for the induction of double-strand breaks (DSBs) in DNA. Each 125I decay in the DNA of either strain induced one DSB, i.e. proportional to (DSB) = 1.0. For the recA strain, proportional to (lethal) = 0.9 and for the rec+ strain, 0.4. Assays for biological repair of DSBs, involving incubation of thawed samples in growth-medium at 370C before the extraction of DNA, demonstrated significant repair of 125I-induced DSBs by rec+ cells but none by recA cells. For small numbers of decays, there was approximately a 1 : 1 correlation, for either strain, between lethal decays and post-incubation residual DSBs. Comparison with data for larger numbers of decays indicated that a typical rec+ cell can repair no more than three to four DSBs per completed genome (2.5 x 109 daltons). (author)

  6. 125I brachytherapy alone for recurrent or locally advanced adenoid cystic carcinoma of the oral and maxillofacial region

    Background and purpose: This retrospective study was to evaluate the local control and survival of 125I brachytherapy for recurrent and/or locally advanced adenoid cystic carcinoma (ACC) of the oral and maxillofacial region. Patients and methods: A total of 38 patients with recurrent and/or locally advanced ACC of the oral and maxillofacial region received 125I brachytherapy alone from 2001-2010. Twenty-nine were recurrent cases following previous surgery and radiation therapy. The other 9 cases involved primary tumors. Overall, 12 tumors were located in the major salivary glands, 12 in the minor salivary glands, and 14 in the paranasal region, the nasal cavity or the skull base. The prescribed dose was 100-160 Gy. Results: Patients were followed for 12-122 months (median 51 months). The 2-, 5-, and 10-year local tumor control rates were 86.3, 59, and 31.5 %, respectively. The 2-, 5-, and 10-year overall survival rates were 92.1, 65 and 34.1 %, respectively. Tumors > 6 cm had significantly lower local control and survival rates. No severe complications were observed during follow-up. Conclusion: 125I brachytherapy is a feasible and effective modality for the treatment of locally advanced unresectable or recurrent ACC. (orig.)

  7. {sup 125}I brachytherapy alone for recurrent or locally advanced adenoid cystic carcinoma of the oral and maxillofacial region

    Huang, M.W.; Zheng, L.; Liu, S.M.; Shi, Y.; Zhang, J.; Yu, G.Y.; Zhang, J.G. [Peking Univ. School and Hospital of Stomatology, Beijing (China). Dept. of Oral and Maxillofacial Surgery

    2013-06-15

    Background and purpose: This retrospective study was to evaluate the local control and survival of {sup 125}I brachytherapy for recurrent and/or locally advanced adenoid cystic carcinoma (ACC) of the oral and maxillofacial region. Patients and methods: A total of 38 patients with recurrent and/or locally advanced ACC of the oral and maxillofacial region received {sup 125}I brachytherapy alone from 2001-2010. Twenty-nine were recurrent cases following previous surgery and radiation therapy. The other 9 cases involved primary tumors. Overall, 12 tumors were located in the major salivary glands, 12 in the minor salivary glands, and 14 in the paranasal region, the nasal cavity or the skull base. The prescribed dose was 100-160 Gy. Results: Patients were followed for 12-122 months (median 51 months). The 2-, 5-, and 10-year local tumor control rates were 86.3, 59, and 31.5 %, respectively. The 2-, 5-, and 10-year overall survival rates were 92.1, 65 and 34.1 %, respectively. Tumors > 6 cm had significantly lower local control and survival rates. No severe complications were observed during follow-up. Conclusion: {sup 125}I brachytherapy is a feasible and effective modality for the treatment of locally advanced unresectable or recurrent ACC. (orig.)

  8. Cellular uptake of 125I-mIBG and of 111In-pentetreotide by human neuroblastoma cells in culture

    Aim. Neuroblastoma have various prognosis, leading or not to heavy therapeutics. MIBG scan is the reference for assessment of the disease extent, but somatostatin analogs are promising as somatostatin receptors expression might indicate neuroendocrine tumoral cell differentiation. The aim of our study was to establish an experimental model to assess cellular uptake of 125I-meta-iodo-benzyl-guanidine (125I-mIBG) and of 111In pentetreotide (111In-OCT), by neuroblastoma cells culture. Material and methods. We compared the uptake of these tracers by SK-N-SH human neuroblastoma cell line in monolayer culture. After cell characterization, toxicity of ligands and of their competitive inhibitors was studied. Experiments with separate incubation of each tracer, using different times and concentrations, determined optimal conditions, which were then applied to simultaneous incubation studies. Results. Total uptakes after simultaneous 3 h-incubation with 125I-mIBG (106 M) and 111In-OCT (108 M) (respectively 3.5 % and 0.03 % of administered activity per 105 cells) were not different from total uptake with separate incubation. Conclusions. Our results confirms the validity of the methodology which is now under use to study the influence of cell differentiation on cellular uptake. (authors)

  9. Binding of [125I]iodipine to parathyroid cell membranes: Evidence of a dihydropyridine-sensitive calcium channel

    The parathyroid cell is unusual, in that an increase in extracellular calcium concentrations inhibits PTH release. Calcium channels are glycoproteins that span cell membranes and allow entry of extracellular calcium into cells. We have demonstrated that the calcium channel agonist (+)202-791, which opens calcium channels, inhibits PTH release and that the antagonist (-)202-791, which closes calcium channels, stimulates PTH release. To identify the calcium channels responsible for these effects, we used a radioligand that specifically binds to calcium channels. Bovine parathyroid cell membranes were prepared and incubated under reduced lighting with [125I] iodipine (SA, 2000 Ci/mmol), which recognizes 1,4-dihydropyridine-sensitive calcium channels. Bound ligand was separated from free ligand by rapid filtration through Whatman GF/B filters. Nonspecific binding was measured by the inclusion of nifedipine at 10 microM. Specific binding represented approximately 40% of the total binding. The optimal temperature for [125I] iodipine binding was 4 C, and binding reached equilibrium by 30 min. The equilibrium dissociation constant (Kd) was approximately 550 pM, and the maximum number of binding sites was 780 fmol/mg protein. Both the calcium channel agonist (+)202-791 and antagonist (-)202-791 competitively inhibited [125I] iodipine binding, with 50% inhibition concentrations of 20 and 300 nM, respectively. These data indicate the presence of dihydropyridine-sensitive calcium channels on parathyroid cell membranes

  10. A specific assay measuring binding of 125I-Gp 120 from HIV to T4+/CD4+ cells

    The HIV (HTLV-III) envelope glycoprotein, Gp120, was isolated from virus-infected tissue culture cells using affinity chromatography. A radioimmunoassay was developed to determine the degree of iodinated Gp120 to target CD4+ (T4+) cells. 125I-Gp120 could be shown to selectively bind to CD4+ cells only. The Gp120 remained bound to these cells after repeated washes. Monoclonal anti-CD4 antibodies block the binding of Gp120 to CD4+ cells. Monoclonal antibodies to other cell surface components do not interfere with 125I-Gp120 binding. All IgG antibodies from HIV seropositive donors tested block 125I-GP120 binding, though with variable titers. The authors believe that this assay provides further proof for the use of CD4 (T4) as a component of the receptor for HIV. It represents a safe, objective and sensitive method for the analysis of Gp120-CD4 interactions, as well as the potential of antibodies to interfere with this binding. (Auth.)

  11. Immunoassay of 5-methyltetrahydrofolate: use of 125I-labeled protein A as the tracer molecule for specific antibody

    A sensitive and specific solid-phase radioimmunoassay for 5-methyltetrahydrofolate (5-MTHFA) has been developed. 125I-Labeled staphylococcal Protein A (125I-PA) was used as the tracer molecule for rabbit IgG antibodies bound to 5-MTHFA immobilized on polyacrylamide beads. The dose-dependent inhibition of antibody binding by fluid-phase drug was reflected in decreased binding of 125I-PA. This inhibition, determined in the presence of known amounts of 5-MTHFA, served as the basis for quantification of 5-MTHFA in test samples. An early bleeding was relatively specific; 4.5 ng 5-MTHFA inhibited immune binding by 50% compared to 7700 ng folinic acid or 1200 ng tetrahydrofolate. Other folic acid analogs, including methotrexate, failed to inhibit significantly. The assay using a later bleeding was more sensitive since 1.6 ng 5-MTHFA gave 50% inhibition (detection limit 0.2 ng), but folinic acid cross-reacted significantly. Absorption with immobilized folinic acid markedly enhanced the specificity of this antiserum and resulted in a 15 to 20% increase in maximum inhibition by 5-MTHFA. The assay could be carried out in the presence of 0.025 ml human serum or urine without affecting the standard curve, and was used to determine levels of 5-MTHFA in serum of drug-treated rabbits

  12. Sensitive measurement of endotoxin by radio-rocket immunoelectrophoresis using [125I]Staphylococcus aureus protein A

    Antibody directed against the core glycolipid antigen (CGL) of the mutant Salmonella minnesota Re 595 has been shown to cross-react with endotoxin from bacteria within the group Enterobacteriaceae. Using this cross-reactive CGL antibody the authors have developed a sensitive (250 pg) radio-rocket immunoelectrophoretic technique to measure endotoxin. They used the principles of rocket immunoelectrophoresis and increased the sensitivity by using 125I-labelled staphylococcal protein A which serves as a sensitive probe to bind to the Fc portion of the IgG complexed with antigen. The rocket-shaped [125I]protein A labelled immune complexes were detected by radioautography. The sensitivity is 100-fold greater than conventional Coomassie brilliant blue staining. Measurement of CGL was inhibited by normal human serum. However, the assay had the capacity to quantitate endotoxin in buffer extracts of clinically isolated Escherichia coli, Serratia marcescens, Klebsiella pneumoniae but not Pseudomonas aeruginosa. Analysis of various preparations of CGL obtained from different investigators demonstrated wide variation in their immunoreactivity. Because of the significant cross-reaction to detect various endotoxins this method has the potential to measure endotoxemia and assess the immunochemical quality of various endotoxin preparations. Additionally, the techniques of using [125I]protein A has wide applicability for the sensitive measurement of other antigens. (Auth.)

  13. Comparative sensitivity of 125I-protein A and enzyme-conjugated antibodies for detection of immunoblotted proteins

    Immunoblotting is a powerful technique for the detection of small amounts of immunologically interesting proteins in unpurified preparations. Iodinated protein A (PA) has been widely used as a second antibody for detection of proteins; however, it does not bind equally well to immunoglobulins from different species nor does it bind to all subclasses of immunoglobulin G (IgG). We compared the sensitivity of [125I]PA with those of both horseradish peroxidase-conjugated second antibodies (HRP) and glucose oxidase-anti-glucose oxidase (GAG) soluble complexes for visualizing bovine serum albumin, human IgG, or human C3 which was either dot blotted or electroblotted to nitrocellulose. [125I]PA was uniformly 10- to 100-fold less sensitive than either HRP or GAG. GAG was more sensitive than HRP except for C3 (electroblotting) and bovine serum albumin and IgG (dot blotting), in which they were equivalent. In general, dot blotting was 10- to 1000-fold more sensitive than electroblotting. Although relative sensitivities varied depending on the proteins analyzed and the antisera used, GAG appeared to be superior to [125I]PA and HRP for detection of immunoblotted proteins

  14. Evaluation of new iodinated acridine derivatives for targeted radionuclide therapy of melanoma using 125I, an Auger electron emitter.

    Gardette, Maryline; Papon, Janine; Bonnet, Mathilde; Desbois, Nicolas; Labarre, Pierre; Wu, Ting-Dee; Miot-Noirault, Elisabeth; Madelmont, Jean-Claude; Guerquin-Kern, Jean-Luc; Chezal, Jean-Michel; Moins, Nicole

    2011-12-01

    The increasing incidence of melanoma and the lack of effective therapy on the disseminated form have led to an urgent need for new specific therapies. Several iodobenzamides or analogs are known to possess specific affinity for melanoma tissue. New heteroaromatic derivatives have been designed with a cytotoxic moiety and termed DNA intercalating agents. These compounds could be applied in targeted radionuclide therapy using (125)I, which emits Auger electrons and gives high-energy, localized irradiation. Two iodinated acridine derivatives have been reported to present an in vivo kinetic profile conducive to application in targeted radionuclide therapy. The aim of the present study was to perform a preclinical evaluation of these compounds. The DNA intercalating property was confirmed for both compounds. After radiolabeling with (125)I, the two compounds induced in vitro a significant radiotoxicity to B16F0 melanoma cells. Nevertheless, the acridine compound appeared more radiotoxic than the acridone compound. While cellular uptake was similar for both compounds, SIMS analysis and in vitro protocol showed a stronger affinity for melanin with acridone derivative, which was able to induce a predominant scavenging process in the melanosome and restrict access to the nucleus. In conclusion, the acridine derivative with a higher nuclear localization appeared a better candidate for application in targeted radionuclide therapy using (125)I. PMID:20567996

  15. Experimental study on bone mineral determination in the wound healing process after tooth extraction by 125I-photon absorptiometry

    A study was carried out by 125I-photon absorptiometry in tooth extraction wounds of dogs to determine the bone mineral content of the mandibular premolar region. The bone mineral content of excised mandibles was measured on the 3rd, 7th, 14th, 21st, 28th, 56th, and the 84th day, respectively, after tooth extraction. These were then compared with the values obtained by photodensitometry and by histological findings. The bone mineral content obtained by 125I-photon absorptiometry varied within a range of 0.270 and 0.720 g/cm2, over a period of 84-days. The highest mineral content value was noted in the apical site. Lower values were noted in the central site and with still lower values in the marginal site. In each case the bone mineral content which deacreased on the 3rd and 7th day after extraction tended to increase gradually thereafter. On the 56th and 84th day after tooth extraction, an increase in bone mineral in the margical site and a deacrease in the apical site was observed. This observation indicated that homogenization of the bone mineral