Science.gov

Sample records for 125i seed localization

  1. Localization of linked {sup 125}I seeds in postimplant TRUS images for prostate brachytherapy dosimetry

    SciTech Connect

    Xue Jinyu . E-mail: Jinyu.Xue@mail.tju.edu; Waterman, Frank; Handler, Jay; Gressen, Eric

    2005-07-01

    Purpose: To demonstrate that {sup 125}I seeds can be localized in transrectal ultrasound (TRUS) images obtained with a high-resolution probe when the implant is performed with linked seeds and spacers. Adequate seed localization is essential to the implementation of TRUS-based intraoperative dosimetry for prostate brachytherapy. Methods and Materials: Thirteen preplanned peripherally loaded prostate implants were performed using {sup 125}I seeds and spacers linked together in linear arrays that prevent seed migration and maintain precise seed spacing. A set of two-dimensional transverse images spaced at 0.50-cm intervals were obtained with a high-resolution TRUS probe at the conclusion of the procedure with the patient still under anesthesia. The image set extended from 1.0 cm superior to the base to 1.0 cm inferior to the apex. The visible echoes along each needle track were first localized and then compared with the known construction of the implanted array. The first step was to define the distal and proximal ends of each array. The visible echoes were then identified as seeds or spacers from the known sequence of the array. The locations of the seeds that did not produce a visible echo were interpolated from their known position in the array. A CT scan was obtained after implantation for comparison with the TRUS images. Results: On average, 93% (range, 86-99%) of the seeds were visible in the TRUS images. However, it was possible to localize 100% of the seeds in each case, because the locations of the missing seeds could be determined from the known construction of the arrays. Two factors complicated the interpretation of the TRUS images. One was that the spacers also produced echoes. Although weak and diffuse, these echoes could be mistaken for seeds. The other was that the number of echoes along a needle track sometimes exceeded the number of seeds and spacers implanted. This was attributed to the overall length of the array, which was approximately 0.5 cm

  2. Imaging Factors That Influence Surgical Margins After Preoperative 125I Radioactive Seed Localization of Breast Lesions: Comparison With Wire Localization

    PubMed Central

    Dryden, Mark J.; Dogan, Basak E.; Fox, Patricia; Wang, Cuiyan; Black, Dalliah M.; Hunt, Kelly; Yang, Wei Tse

    2016-01-01

    Objective The objective of this study was to compare the potential Influence of imaging variables on surgical margins after preoperative radioactive seed localization (RSL) and wire localization (WL) techniques. Materials and Methods A total of 565 women with 660 breast lesions underwent RSL or WL between May 16, 2012, and May 30, 2013. Patient age, lesion type (mass, calcifications, mass with associated calcifications, other), lesion size, number of seeds or wires used, surgical margin status (close positive or negative margins), and reexcision and mastectomy rates were recorded. Results Of 660 lesions, 127 (19%) underwent RSL and 533 (81%) underwent WL pre-operatively. Mean lesion size was 1.8 cm in the RSL group and 1.8 cm in the WL group (p = 0.35). No difference in lesion type was identified in the RSL and WL groups (p = 0.63). RSL with a single seed was used in 105 of 127 (83%) RSLs compared with WL with a single wire in 349 of 533 (65%) WLs (p = 0.0003). The number of cases with a close positive margin was similar for RSLs (26/127, 20%) and WLs (104/533, 20%) (p = 0.81). There was no difference between the RSL group and the WL group in close positive margin status (20% each, p = 0.81), reexcision rates (20% vs 16%, respectively; p = 0.36), or mastectomy rates (6% each, p = 0.96). Lesions containing calcifications were more likely to require more than one wire (odds ratio [OR], 4.44; 95% CI, 2.8–7.0) or more than one seed (OR, 7.03; 95% CI, 1.6–30.0) when compared with masses alone (p < 0.0001). Increasing lesion size and the presence of calcifications were significant predictors of positive margins, whereas the use of more than one wire or seed was not (OR, 0.9; 95% CI, 0.5–1.5) (p = 0.75). Conclusion Close positive margin, reexcision, and mastectomy rates remained similar in the WL group and RSL group. The presence of calcifications and increasing lesion size increased the odds of a close positive margin in both the WL and RSL groups, whereas the use

  3. Novel Silicone-Coated 125I Seeds for the Treatment of Extrahepatic Cholangiocarcinoma

    PubMed Central

    Zhang, Weixing; Cai, Xiaobo; Chen, Dafan; Wan, Xinjian

    2016-01-01

    125I seeds coated with titanium are considered a safe and effective interstitial brachytherapy for tumors, while the cost of 125I seeds is a major problem for the patients implanting lots of seeds. The aim of this paper was to develop a novel silicone coating for 125I seeds with a lower cost. In order to show the radionuclide utilization ratio, the silicone was coated onto the seeds using the electro-spinning method and the radioactivity was evaluated, then the anti-tumor efficacy of silicone 125I seeds was compared with titanium 125I seeds. The seeds were divided into four groups: A (control), B (pure silicone), C (silicone 125I), D (titanium 125I) at 2 Gy or 4 Gy. Their anti-tumour activity and mechanism were assessed in vitro and in vivo using a human extrahepatic cholangiocarcinoma cell line FRH-0201 and tumor-bearing BALB/c nude mice. The silicone 125I seeds showed higher radioactivity; the rate of cell apoptosis in vitro and the histopathology in vivo demonstrated that the silicone 125I seeds shared similar anti-tumor efficacy with the titanium 125I seeds for the treatment of extrahepatic cholangiocarcinoma, while they have a much lower cost. PMID:26840346

  4. Bioevaluation of 125I Ocu-Prosta seeds for application in prostate cancer brachytherapy

    PubMed Central

    Mukherjee, Archana; Sarma, Haladhar Dev; Saxena, Sanjay; Kumar, Yogendra; Chaudhari, Pradip; Goda, Jayant Sastri; Adurkar, Pranjal; Dash, Ashutosh; Samuel, Grace

    2014-01-01

    Background & objectives: In recent years, brachytherapy involving permanent radioactive seed implantation has emerged as an effective modality for the management of cancer of prostate. 125I-Ocu-Prosta seeds were indigenously developed and studies were carried out to assess the safety of the indigenously developed 125I-Ocu-Prosta seeds for treatment of prostate cancer. Methods: Animal experiments were performed to assess the likelihood of in vivo release of 125I from radioactive seeds and migration of seeds implanted in the prostate gland of the rabbit. In vivo release of 125I activity was monitored by serial blood sampling from the auricular vein and subsequent measurement of 125I activity. Serial computed tomography (CT) scans were done at regular intervals till 6 months post implant to assess the physical migration of the seeds. Results: The laser welded seeds maintained their hermeticity and prevented the in vivo release of 125I activity into the blood as no radioactivity was detected during follow up blood measurements. Our study showed that the miniature 125I seeds were clearly resolved in CT images. Seeds remained within the prostate gland during the entire study period. Moreover, the seed displacement was minimal even within the prostate gland. Interpretation & conclusions: Our findings have demonstrated that indigenously developed 125I-Ocu-Prosta seeds may be suitable for application in treatment of prostate cancer. PMID:24927341

  5. 125I Seed Permanent Implantation as a Palliative Treatment for Stage III and IV Hypopharyngeal Carcinoma

    PubMed Central

    Li, Lei; Yang, Jie; Li, Xiaojiang; Wang, Xiaoli; Ren, Yanxin; Fei, Jimin; Xi, Yan; Sun, Ruimei; Ma, Jing

    2016-01-01

    Objectives. The aim of this study was to investigate the feasibility and safety of percutaneous 125I seed permanent implantation for advanced hypopharyngeal carcinoma from toxicity, tumor response, and short-term outcome. Methods. 125I seeds implant procedures were performed under computed tomography for 34 patients with advanced hypopharyngeal carcinoma. We observed the local control rate, overall survival, and acute or late toxicity rate. Results. In the 34 patients (stage III, n=6; stage IV, n=28), the sites of origin were pyriform sinus (n=29) and postcricoid area (n=5). All patients also received one to four cycles of chemotherapy after seed implantation. The post-plan showed that the actuarial D90 of 125I seeds ranged from 90 to 158 Gy (median, 127 Gy). The mean follow-up was 12.3 months (range, 3.4 to 43.2 months). The local control was 2.1–31.0 months with a median of 17.7 months (95% confidence interval [CI], 13.4 to 22.0 months). The 1-, 2-, and 3-year local controls were 65.3%, 28.6%, and 9.5% respectively. Twelve patients (35%) died of local recurrence, fourteen patients (41%) died of distant metastases, and three patients (9%) died of recurrence and metastases at the same time. Five patients (15%) still survived to follow-up. At the time of analysis, the median survival time was 12.5 months (95% CI, 9.5 to 15.4 months). The 1-, 2-, and 3-year overall survival rates were 55.2%, 20.3%, and 10.9%, respectively. Five patients (15%) experienced grade 3 toxic events and nine patients (26%) have experienced grade 2 toxic events. Conclusion. This review shows relatively low toxicity for interstitial 125I seed implantation in the patients with advanced stage hypopharyngeal cancer. The high local control results suggest that 125I seed brachytherapy implant as a salvage or palliative treatment for advanced hypopharyngeal carcinoma merit further investigation. PMID:27440132

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

    SciTech Connect

    Wang, Zhongmin; Lu, Jian; Gong, Ju; Zhang, Liyun; Xu, Yingjia; Song, Shaoli; Chen, Kemin; Liu, Fenju; Gang, Huang

    2013-04-12

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

  7. 125I Seed Implant Brachytherapy for Painful Bone Metastases After Failure of External Beam Radiation Therapy

    PubMed Central

    Feng, Shi; Wang, Li; Xiao, Zhang; Maharjan, Rakesh; Chuanxing, Li; Fujun, Zhang; Jinhua, Huang; Peihong, Wu

    2015-01-01

    Abstract The purpose of this study was to evaluate the safety and therapeutic efficacy of computed tomography (CT)-guided 125I seed implant brachytherapy in patients with painful metastatic bone lesions after failure of external beam radiation therapy (EBRT). From August 2012 to July 2014, 26 patients with painful bone metastases after failure of EBRT were treated with CT-guided 125I seed implant brachytherapy. Patient pain and analgesic use were measured using the Brief Pain Inventory before treatment, weekly for 4 weeks, and every 4 weeks thereafter for a total of 24 weeks. Opioid analgesic medications and complications were monitored at the same follow-up intervals. Before 125I seed implantation, the mean score for worst pain in a 24-hour period was 7.3 out of 10. Following treatment, at weeks 1, 4, 8, 12, and 24, worst pain decreased to 5.0 (P < 0.0001), 3.0 (P < 0.0001), 2.8 (P < 0.0001), 2.6 (P < 0.0001), and 2.0 (P = 0.0001), respectively. Opioid usage significantly decreased at weeks 4, 8, and 12. Overall response rates of osseous metastases after 125I seed implantation at 1, 4, 8, 12, and 24 weeks were 58%, 79%, 81%, 82%, and 80%, respectively. Adverse events were seen in 4 patients, including Grade 1 myelosuppression and Grade 1 late skin toxicity. 125I seed brachytherapy is a safe and effective treatment for patients with painful bone metastases after failure of EBRT. PMID:26252288

  8. Preventive effects of 125I seeds on benign restenosis following esophageal stent implantation in a dog model

    PubMed Central

    GAN, ZHEN; JING, JIAN; ZHU, GUANGYU; QIN, YONGLIN; TENG, GAOJUN; GUO, JINHE

    2015-01-01

    The present study aimed to evaluate the effects of iodine-125 (125I) seeds on the proliferation of primary esophageal fibroblasts in dogs, and to assess the safety and preventive efficacy of 125I seed-pre-loaded esophageal stents in benign restenosis following implantation. Primary fibroblasts were cultured with various 125I seed activities, which were then evaluated using cell proliferation and apoptosis assays as well as cell cycle analysis using Annexin V/propidium iodide (PI) double staining and PI staining. Prior to sacrification, animals were submitted to esophageal radiography under digital subtraction angiography. Esophageal tissues were collected and examined for macroscopic, microscopic and pathological alterations. The results demonstrated a significant and dose-dependent inhibition of fibroblast proliferation and increased apoptosis following exposure to 125I seeds. G0/G1 fibroblast populations increased in a dose-dependent manner following treatment with 125I seeds, in contrast to cells in S phase. Four weeks following implantation, α-smooth muscle actin and proliferating cell nuclear antigen expression levels in the experimental group were significantly lower compared with those in the control group; in addition, eight weeks following implantation, esophageal inner diameters were increased in the experimental group. 125I seeds inhibited proliferation of dog esophageal fibroblasts via cell cycle arrest and apoptosis. In conclusion, 125I seed-pre-loaded esophageal stents inhibited benign hyperplasia in the upper edge of the stent to a certain extent, which relieved benign restenosis following implantation with a good safety profile. PMID:25543838

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

    PubMed Central

    2011-01-01

    Background The aim was to determine the incidence of seed migration not only to the chest, but also to the abdomen and pelvis after transperineal interstitial prostate brachytherapy with loose 125I seeds. Methods We reviewed the records of 267 patients who underwent prostate brachytherapy with loose 125I seeds. After seed implantation, orthogonal chest radiographs, an abdominal radiograph, and a pelvic radiograph were undertaken routinely to document the occurrence and sites of seed migration. The incidence of seed migration to the chest, abdomen, and pelvis was calculated. All patients who had seed migration to the abdomen and pelvis subsequently underwent a computed tomography scan to identify the exact location of the migrated seeds. Postimplant dosimetric analysis was undertaken, and dosimetric results were compared between patients with and without seed migration. Results A total of 19,236 seeds were implanted in 267 patients. Overall, 91 of 19,236 (0.47%) seeds migrated in 66 of 267 (24.7%) patients. Sixty-nine (0.36%) seeds migrated to the chest in 54 (20.2%) patients. Seven (0.036%) seeds migrated to the abdomen in six (2.2%) patients. Fifteen (0.078%) seeds migrated to the pelvis in 15 (5.6%) patients. Seed migration occurred predominantly within two weeks after seed implantation. None of the 66 patients had symptoms related to the migrated seeds. Postimplant prostate D90 was not significantly different between patients with and without seed migration. Conclusion We showed the incidence of seed migration to the chest, abdomen and pelvis. Seed migration did not have a significant effect on postimplant prostate D90. PMID:21974959

  10. Effect of pedicle fixation combined with 125I seed implantation for metastatic thoracolumbar tumors

    PubMed Central

    Qian, Jiale; Bao, Zhaohua; Zou, Jun; Yang, Huilin

    2016-01-01

    Purpose The aim of this study was to investigate the clinical efficacy of pedicle fixation combined with 125I brachytherapy in treating metastatic thoracolumbar tumors. Patients and methods A retrospective analysis of the clinical data of seven metastatic thoracolumbar tumor patients who received pedicle fixation combined with radioactive 125I seed implantation brachytherapy in our department between January 2009 and December 2013 was performed. The visual analog scale (VAS) for pain and the Karnofsky performance status (KPS) score before the operation and 1, 6, and 12 months after the operation were observed and recorded. The changes in the scores at each time point were compared. Results All the patients underwent a successful operation, without any complications during their hospitalization. All the patients received postoperative follow-up, and the duration of follow-up was 15–50 months, with an average of 32.2 months. One pancreatic cancer patient died of liver failure and hypoproteinemia 28 months post surgery. The VAS scores of patients before the operation and 1, 6, and 12 months after the operation were 7.43±0.98, 2.71±0.49, 3.00±0.82, and 4.29±0.98, respectively; the KPS scores were 52.9±9.5, 84.3±5.3, 75.7±5.3, and 72.9±4.9, respectively. These results suggest that the VAS score at each time point was significantly decreased compared with that before the operation, while the KPS score was significantly increased compared with that before the operation. Both differences had statistical significance (P<0.05). Conclusion As a therapy for advanced malignant tumors with thoracolumbar metastasis, pedicle fixation combined with 125I brachytherapy can effectively relieve short-term pain and improve patient’s quality of life. PMID:27274307

  11. New National Air-Kerma-Strength Standards for 125I and 103Pd Brachytherapy Seeds

    PubMed Central

    Seltzer, Stephen M.; Lamperti, Paul J.; Loevinger, Robert; Mitch, Michael G.; Weaver, James T.; Coursey, Bert M.

    2003-01-01

    The new U.S. measurement standard for the air-kerma strength from low-energy photon-emitting brachytherapy seed sources is formally described in detail. This instrument-based standard was implemented on 1 January 1999, with its salient features and the implications of differences with the previous standard given only through a series of informal communications. The Wide-Angle Free-Air Chamber (WAFAC) is specially designed to realize air kerma from a single-seed source emitting photons with energies up to about 40 keV, and is now used to measure the wide variety of seeds used in prostate-cancer therapy that has appeared in the last few years. For the two 125I seed models that have been subject to both the old and new standards, the new standard reduces the air-kerma strength by 10.3 %. This change is mainly due to the removal of the influence on the measurement of the Ti K x rays produced in the source encapsulation, a component with no clinical significance. PMID:27413614

  12. Localization of [125I]endothelin-1 in injured aorta of rabbits.

    PubMed

    Kurata, C; Callahan, R J; Molea, N; Wilkinson, R; Fischman, A J; Strauss, H W

    1995-07-01

    Endothelin-1 is a potent vasoconstrictor. This study was performed to determine whether arterial injury, induced by either hypercholesterolemia or mechanical disruption of the endothelium, is associated with increased localization of endothelin-1 in the artery. The blood clearance and tissue distribution of intravenously injected [125I]endothelin-1 was evaluated in 33 rabbits--control animals (n = 7), balloon de-endothelialized animals (n = 12), cholesterol-fed animals (n = 6) and animals that had both balloon de-endothelialization and high cholesterol diet (n = 8). The blood clearance half time was less than 10 min, with slightly slower clearance in the ballooned/cholesterol-fed animals. [125I]Endothelin-1 localized in the lung (approximately 12% injected dose (ID)/organ) and kidney (approximately 8%ID/organ). [125I]Endothelin-1 localization in the injured aorta increased from the baseline level of 0.06%kgID/g to its highest level within 5 min of balloon de-endothelialization (0.2%kgID/g) and decreased to 0.11%kgID/g within one week and remained essentially unchanged through 16 weeks. The area with increased binding of [125I]endothelin-1 corresponded to the zone of arterial injury stained with Evans blue. On the other hand, the binding in the aorta did not increase with the atherogenic diet. These findings suggest that endothelin-1 accumulates in injured vessels, attaining the highest levels immediately after mechanical injury.

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

    SciTech Connect

    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.

  14. The use of new GAFCHROMIC EBT film for {sup 125}I seed dosimetry in Solid Water phantom

    SciTech Connect

    Chiu-Tsao, Sou-Tung; Medich, David; Munro, John III

    2008-08-15

    Radiochromic film dosimetry has been extensively used for intravascular brachytherapy applications for near field within 1 cm from the sources. With the recent introduction of new model of radiochromic films, GAFCHROMIC EBT, with higher sensitivity than earlier models, it is promising to extend the distances out to 5 cm for low dose rate (LDR) source dosimetry. In this study, the use of new model GAFCHROMIC EBT film for {sup 125}I seed dosimetry in Solid Water was evaluated for radial distances from 0.06 cm out to 5 cm. A multiple film technique was employed for four {sup 125}I seeds (Implant Sciences model 3500) with NIST traceable air kerma strengths. Each experimental film was positioned in contact with a {sup 125}I seed in a Solid Water phantom. The products of the air kerma strength and exposure time ranged from 8 to 3158 U-h, with the initial air kerma strength of 6 U in a series of 25 experiments. A set of 25 calibration films each was sequentially exposed to one {sup 125}I seed at about 0.58 cm distance for doses from 0.1 to 33 Gy. A CCD camera based microdensitometer, with interchangeable green (520 nm) and red (665 nm) light boxes, was used to scan all the films with 0.2 mm pixel resolution. The dose to each {sup 125}I calibration film center was calculated using the air kerma strength of the seed (incorporating decay), exposure time, distance from seed center to film center, and TG43U1S1 recommended dosimetric parameters. Based on the established calibration curve, dose conversion from net optical density was achieved for each light source. The dose rate constant was determined as 0.991 cGy U{sup -1} h{sup -1} ({+-}6.9%) and 1.014 cGy U{sup -1} h{sup -1} ({+-}6.8%) from films scanned using green and red light sources, respectively. The difference between these two values was within the uncertainty of the measurement. Radial dose function and 2D anisotropy function were also determined. The results obtained using the two light sources corroborated each

  15. Ejaculatory Function After Permanent {sup 125}I Prostate Brachytherapy for Localized Prostate Cancer

    SciTech Connect

    Huyghe, Eric Delannes, Martine; Wagner, Fabien M.; Delaunay, Boris; Nohra, Joe; Thoulouzan, Matthieu; Shut-Yee, J. Yeung; Plante, Pierre; Soulie, Michel; Thonneau, Patrick; Bachaud, Jean Marc

    2009-05-01

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

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

    SciTech Connect

    Martinez, A.; Goffinet, D.R.; Fee, W.; Goode, R.; Cox, R.S.

    1983-03-15

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

  17. Characteristics and autoradiographic localization of 2-( sup 125 I)iodomelatonin binding sites in Djungarian hamster brain

    SciTech Connect

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

    1989-08-01

    These studies investigated the characteristics and regional distribution of 2-({sup 125}I)iodomelatonin binding in Djungarian hamster brain. The results showed that 2-({sup 125}I)iodomelatonin labels two types of binding sites, which resemble the ML-1 and ML-2 melatonin subtypes previously described in other tissues. The 2-({sup 125}I)iodomelatonin binding site identified in whole brain membranes has a nanomolar affinity (Kd = 1.48 +/- 0.26 nM) and biochemical and pharmacological characteristics identical to those of the ML-2 site of Syrian hamster whole brain. The 2-({sup 125}I)iodomelatonin site in the hypothalamus has a picomolar affinity (Kd = 43.4 +/- 5.1 pM) and resembles the ML-1 site of chicken retina. The localization of 2-({sup 125}I)iodomelatonin labeling in autoradiographic studies of the Djungarian hamster brain includes the suprachiasmatic nuclei, the median eminence, the reuniens nucleus, and the paraventricular nucleus of the thalamus.

  18. Sequential Comparison of Seed Loss and Prostate Dosimetry of Stranded Seeds With Loose Seeds in {sup 125}I Permanent Implant for Low-Risk Prostate Cancer

    SciTech Connect

    Saibishkumar, Elantholi P.; Borg, Jette; Yeung, Ivan; Cummins-Holder, Cheryl; Landon, Angela; Crook, Juanita

    2009-01-01

    Purpose: To compare stranded seeds (SSs) with loose seeds (LSs) in terms of prostate edema, dosimetry, and seed loss after {sup 125}I brachytherapy. Methods and Materials: Two prospective cohorts of 20 men participated in an institutional review board-approved protocols to study postimplant prostate edema and its effect on dosimetry. The LS cohort underwent brachytherapy between September 2002 and July 2003 and the SS cohort between April 2006 and January 2007. Both cohorts were evaluated sequentially using computed tomography-magnetic resonance imaging fusion-based dosimetry on Days 0, 7, and 30. No hormonal therapy or supplemental beam radiotherapy was used. Results: Prostate edema was less in the SS cohort at all points (p = NS). On Day 0, all the prostate dosimetric factors were greater in the LS group than in the SS group (p = 0.003). However, by Days 7 and 30, the dosimetry was similar between the two cohorts. No seeds migrated to the lung in the SS cohort compared with a total of five seeds in 4 patients in the LS cohort. However, the overall seed loss was greater in the SS cohort (24 seeds in 6 patients; 1.1% of total vs. 0.6% for LSs), with most seeds lost through urine (22 seeds in 5 patients). Conclusion: Despite elimination of venous seed migration, greater seed loss was observed with SSs compared with LSs, with the primary site of loss being the urinary tract. Modification of the technique might be necessary to minimize this. Prostate dosimetry on Days 7 and 30 was similar between the SS and LS cohorts.

  19. Multigroup discrete ordinates modeling of 125I 6702 seed dose distributions using a broad energy-group cross section representation.

    PubMed

    Daskalov, George M; Baker, R S; Rogers, D W O; Williamson, J F

    2002-02-01

    Our purpose in this work is to demonstrate that the efficiency of dose-rate computations in 125I brachytherapy, using multigroup discrete ordinates radiation transport simulations, can be significantly enhanced using broad energy group cross sections without a loss of accuracy. To this end, the DANTSYS multigroup discrete ordinates neutral particle transport code was used to estimate the absorbed dose-rate distributions around an 125I-model 6702 seed in two-dimensional (2-D) cylindrical R-Z geometry for four different problems spanning the geometries found in clinical practice. First, simulations with a high resolution 210 energy groups library were used to analyze the photon flux spectral distribution throughout this set of problems. These distributions were used to design an energy group structure consisting of three broad groups along with suitable weighting functions from which the three-group cross sections were derived. The accuracy of 2-D DANTSYS dose-rate calculations was benchmarked against parallel Monte Carlo simulations. Ray effects were remedied by using the DANTSYS internal first collision source algorithm. It is demonstrated that the 125I primary photon spectrum leads to inappropriate weighting functions. An accuracy of +/-5% is achieved in the four problem geometries considered using geometry-independent three-group libraries derived from either material-specific weighting functions or a single material-independent weighting function. Agreement between Monte Carlo and the three-group DANTSYS calculations, within three standard Monte Carlo deviations, is observed everywhere except for a limited region along the Z axis of rotational symmetry, where ray effects are difficult to mitigate. The three-group DANTSYS calculations are 10-13 times faster than ones with a 210-group cross section library for 125I dosimetry problems. Compared to 2-D EGS4 Monte Carlo calculations, the 3-group DANTSYS simulations are a 100-fold more efficient. Provided that these

  20. Monte Carlo and thermoluminescence dosimetry of the new IsoSeed registered model I25.S17 {sup 125}I interstitial brachytherapy seed

    SciTech Connect

    Lymperopoulou, G.; Papagiannis, P.; Sakelliou, L.; Karaiskos, P.; Sandilos, P.; Przykutta, A.; Baltas, D.

    2005-11-15

    Monte Carlo simulation and experimental thermoluminescence dosimetry were utilized for the dosimetric characterization of the new IsoSeed registered model I25.S17 {sup 125}I interstitial brachytherapy seed. The new seed design is similar to that of the selectSeed and 6711 seeds, with the exception of its molybdenum marker. Full dosimetric data are presented following the recommendations in the Update of the AAPM Task Group 43 report (TG-43U1). A difference of 3.3% was found between Monte Carlo dose rate constant results calculated by air kerma strengths from simulations using a point detector and a detector resembling the solid angle subtended to the seed by the Wide Angle Free Air Chamber (WAFAC) in the primary standard calibration geometry. Following the TG-43U1 recommendations, an average value of {lambda}{sub MC}=(0.929{+-}0.014) cGy h{sup -1} U{sup -1} was adopted for the new seed. This value was then averaged with the measured value of {lambda}{sub EXP}=(0.951{+-}0.044) cGy h{sup -1} U{sup -1} to yield the proposed dose rate constant for the new seed that is equal to {lambda}=(0.940{+-}0.051) cGy h{sup -1} U{sup -1}. The Monte Carlo calculated radial dose function and two-dimensional (2-D) anisotropy function results for the new seed were found in agreement with experimental results to within statistical uncertainty of repeated measurements. Monte Carlo simulations were also performed for {sup 125}I seeds of similar geometry and dimensions for the purpose of comparison. The new seed presents dosimetric characteristics that are very similar to that of the selectSeed. In comparison to the most extensively studied Amersham 6711 seed, the new one presents similar dosimetric characteristics with a slightly reduced dose rate constant (1.5%)

  1. Comparison of permanent 125I seeds implants with two different techniques in 500 cases of prostate cancer

    PubMed Central

    Ricós, Jose Vicente; Tortajada, Maria Isabel; Santos, Miguel Angel; Casanova, Juan; Clemente, Jose; Samper, Josefa; Santamaría, Paula; Arribas, Leoncio

    2015-01-01

    Purpose To perform a comparative study of 500 consecutive 125I seeds implants for intracapsular prostate carcinoma with two techniques differing in terms of both strand implantation and planning. Material and methods From 2002 to 2007 we performed 250 implants with fixed stranded seeds (RapidStrand™) and a preplanning system and from 2007 to 2010, 250 with real-time and ProLink™ system. Mean age was 68 and 66, respectively, median PSA (prostate-specific antigen) 7.3 and 7.2, stage T1-T2a in 98% and 94%, and Gleason ≤ 6 in 96% and 86%. Low risk cases were 81% and 71%. The prescribed dose was 145 Gy to the prostate volume, or 108 Gy plus EBRT 46 Gy in some intermediate risk cases. Hormonal treatment was given to 42% and 28%. Results Median follow-up was 48 and 47 months, respectively, 14 patients in the first group and 7 patients in the second developed biochemical failure (BF). Actuarial biochemical relapse-free survival (bRFS) at 5 years increased from 90.2% to 97.2% (low risk from 91.3% to 97.2%, intermediate risk from 84.2% to 97.1%). Biochemical failure was independent of hormone treatment. Rectal complications were G1-2 in 1.2% and 5.2%, respectively. A urinary catheter was necessary in 6.9% and 9.6%, and urethral resection in 1.9% and 4.4%. Genitourinary toxicity was G1-2 in 4.6% and 12%, G3-4 in 1.9% and 4.8%. An assessment of mean D90 in a sample of patients showed that the dosimetry in postoperative planning based on CT improved from a mean D90 of 143 Gy to 157 Gy. Conclusions The outcome of patients with low risk prostate carcinoma treated with 125I seed is very good with low complications rate. The real-time approach in our hands achieved a more precise seed implantation, better dosimetry, and a statistically non-significant better biochemical control. We have made this our standard technique. PMID:26622228

  2. Characterization of the PTW SourceCheck ionization chamber with the Valencia lodgment for (125)I seed verification.

    PubMed

    Tornero-López, Ana M; Torres Del Río, Julia; Ruiz, Carmen; Perez-Calatayud, Jose; Guirado, Damián; Lallena, Antonio M

    2015-12-01

    In brachytherapy using (125)I seed implants, a verification of the air kerma strength of the sources used is required. Typically, between 40 and 100 seeds are implanted. Checking all of them is unaffordable, especially when seeds are disposed in sterile cartridges. Recently, a new procedure allowing the accomplishment of the international recommendations has been proposed for the seedSelectron system of Elekta Brachytherapy. In this procedure, the SourceCheck ionization chamber is used with a special lodgment (Valencia lodgment) that allows to measure up to 10 seeds simultaneously. In this work we analyze this procedure, showing the feasibility of the approximations required for its application, as well as the effect of the additional dependence with the air density that shows the chamber model used. Uncertainty calculations and the verification of the approximation needed to obtain a calibration factor for the Valencia lodgment are carried out. The results of the present work show that the chamber dependence with the air density is the same whether the Valencia lodgment is used or not. On the contrary, the chamber response profile is influenced by the presence of the lodgment. The determination of this profile requires various measurements due to the nonnegligible variability found between different experiments. If it is considered, the uncertainty in the determination of the air-kerma strength increases from 0.5% to 1%. Otherwise, a systematic additional uncertainty of 1% would occur. This could be relevant for the comparison between user and manufacturer measurements that is mandatory in the case studied here.

  3. Y-configured metallic stent combined with 125I seed strands cavity brachytherapy for a patient with type IV Klatskin tumor

    PubMed Central

    Dechao, Jiao; Yanli, Wang; Zhen, Li

    2016-01-01

    We report a case in an inoperable patient with type IV Klatskin tumor treated by the use of a novel, two piece, Y-configured self-expandable metallic stent (SEMS) combined with two 125I seed strands via bilateral approach. The placement of the Y-shaped SEMS was successful and resulted in adequate biliary drainage. After 2 months of intraluminal brachytherapy (ILBT), both 125I seed strands and temporary drainage catheter were removed after patency of the expanded stents was confirmed by the cholangiogram. This technique was feasible and could be considered for the treatment of patients with Bismuth type IV Klatskin tumors.

  4. Y-configured metallic stent combined with 125I seed strands cavity brachytherapy for a patient with type IV Klatskin tumor

    PubMed Central

    Dechao, Jiao; Yanli, Wang; Zhen, Li

    2016-01-01

    We report a case in an inoperable patient with type IV Klatskin tumor treated by the use of a novel, two piece, Y-configured self-expandable metallic stent (SEMS) combined with two 125I seed strands via bilateral approach. The placement of the Y-shaped SEMS was successful and resulted in adequate biliary drainage. After 2 months of intraluminal brachytherapy (ILBT), both 125I seed strands and temporary drainage catheter were removed after patency of the expanded stents was confirmed by the cholangiogram. This technique was feasible and could be considered for the treatment of patients with Bismuth type IV Klatskin tumors. PMID:27648091

  5. Autoradiographic localization of (/sup 125/I-Tyr4)bombesin-binding sites in rat brain

    SciTech Connect

    Zarbin, M.A.; Kuhar, M.J.; O'Donohue, T.L.; Wolf, S.S.; Moody, T.W.

    1985-02-01

    The binding of (/sup 125/I-Tyr/sub 4/)bombesin to rat brain slices was investigated. Radiolabeled (Tyr/sub 4/)bombesin bound with high affinity (K/sub d/ . 4 nM) to a single class of sites (B/sub max/ . 130 fmol/mg of protein); the ratio of specific to nonspecific binding was 6/1. Also, pharmacology studies indicated that the C-terminal of bombesin was important for the high affinity binding activity. Autoradiographic studies indicated that the (/sup 125/I-Tyr4)bombesin-binding sites were discretely distributed in certain gray but not white matter regions of rat brain. Highest grain densities were present in the olfactory bulb and tubercle, nucleus accumbens, suprachiasmatic and periventricular nuclei of the hypothalamus, central medial thalamic nucleus, medial amygdaloid nucleus, hippocampus, dentate gyrus, subiculum, nucleus of the solitary tract, and substantia gelatinosa. Moderate grain densities were present in the parietal cortex, deep layers of the neocortex, rhinal cortex, caudate putamen, stria terminalis, locus ceruleus, parabrachial nucleus, and facial nucleus. Low grain densities were present in the globus pallidus, lateral thalamus, and midbrain. Negligible grain densities were present in the cerebellum, corpus callosum, and all regions treated with 1 microM unlabeled bombesin. The discrete regional distribution of binding suggests that endogenous bombesin-like peptides may function as important regulatory agents in certain brain loci.

  6. Effect of improved TLD dosimetry on the determination of dose rate constants for {sup 125}I and {sup 103}Pd brachytherapy seeds

    SciTech Connect

    Rodriguez, M.; Rogers, D. W. O.

    2014-11-01

    Purpose: To more accurately account for the relative intrinsic energy dependence and relative absorbed-dose energy dependence of TLDs when used to measure dose rate constants (DRCs) for {sup 125}I and {sup 103}Pd brachytherapy seeds, to thereby establish revised “measured values” for all seeds and compare the revised values with Monte Carlo and consensus values. Methods: The relative absorbed-dose energy dependence, f{sup rel}, for TLDs and the phantom correction, P{sub phant}, are calculated for {sup 125}I and {sup 103}Pd seeds using the EGSnrc BrachyDose and DOSXYZnrc codes. The original energy dependence and phantom corrections applied to DRC measurements are replaced by calculated (f{sup rel}){sup −1} and P{sub phant} values for 24 different seed models. By comparing the modified measured DRCs to the MC values, an appropriate relative intrinsic energy dependence, k{sub bq}{sup rel}, is determined. The new P{sub phant} values and relative absorbed-dose sensitivities, S{sub AD}{sup rel}, calculated as the product of (f{sup rel}){sup −1} and (k{sub bq}{sup rel}){sup −1}, are used to individually revise the measured DRCs for comparison with Monte Carlo calculated values and TG-43U1 or TG-43U1S1 consensus values. Results: In general, f{sup rel} is sensitive to the energy spectra and models of the brachytherapy seeds. Values may vary up to 8.4% among {sup 125}I and {sup 103}Pd seed models and common TLD shapes. P{sub phant} values depend primarily on the isotope used. Deduced (k{sub bq}{sup rel}){sup −1} values are 1.074 ± 0.015 and 1.084 ± 0.026 for {sup 125}I and {sup 103}Pd seeds, respectively. For (1 mm){sup 3} chips, this implies an overall absorbed-dose sensitivity relative to {sup 60}Co or 6 MV calibrations of 1.51 ± 1% and 1.47 ± 2% for {sup 125}I and {sup 103}Pd seeds, respectively, as opposed to the widely used value of 1.41. Values of P{sub phant} calculated here have much lower statistical uncertainties than literature values, but

  7. Bystander Effects Induced by Continuous Low-Dose-Rate {sup 125}I Seeds Potentiate the Killing Action of Irradiation on Human Lung Cancer Cells In Vitro

    SciTech Connect

    Chen, H.H. Jia, R.F.; Yu, L.; Zhao, M.J.; Shao, C.L.; Cheng, W.Y.

    2008-12-01

    Purpose: To investigate bystander effects of low-dose-rate (LDR) {sup 125}I seed irradiation on human lung cancer cells in vitro. Methods and Materials: A549 and NCI-H446 cell lines of differing radiosensitivity were directly exposed to LDR {sup 125}I seeds irradiation for 2 or 4 Gy and then cocultured with nonirradiated cells for 24 hours. Induction of micronucleus (MN), {gamma}H2AX foci, and apoptosis were assayed. Results: After 2 and 4 Gy irradiation, micronucleus formation rate (MFR) and apoptotic rate of A549 and NCI-H446 cells were increased, and the MFR and apoptotic rate of NCI-H446 cells was 2.1-2.8 times higher than that of A549 cells. After coculturing nonirradiated bystander cells with {sup 125}I seed irradiated cells for 24 hours, MFR and the mean number of {gamma}H2AX foci/cells of bystander A549 and NCI-H446 cells were similar and significantly higher than those of control (p <0.05), although they did not increase with irradiation dose. However, the proportion of bystander NCI-H446 cells with MN numbers {>=}3 and {gamma}H2AX foci numbers 15-19 and 20-24 was higher than that of bystander A549 cells. In addition, dimethyl sulfoxide (DMSO) treatment could completely suppress the bystander MN of NCI-H446 cells, but it suppressed only partly the bystander MN of A549 cells, indicating that reactive oxygen species are involved in the bystander response to NCI-H446 cells, but other signaling factors may contribute to the bystander response of A549 cells. Conclusions: Continuous LDR irradiation of {sup 125}I seeds could induce bystander effects, which potentiate the killing action on tumor cells and compensate for the influence of nonuniform distribution of radiation dosage on therapeutic outcomes.

  8. Monte Carlo calculations and experimental measurements of the TG-43U1-recommended dosimetric parameters of 125I (Model IR-Seed2) brachytherapy source.

    PubMed

    Sheikholeslami, Sahar; Nedaie, Hasan Ali; Sadeghi, Mahdi; Pourbeigi, Hossein; Shahzadi, Sohrab; Zehtabian, Mehdi; Hasani, Mohsen; Meigooni, Ali S

    2016-01-01

    A new design of 125I (Model IR-Seed2) brachytherapy source has been manufactured recently at the Applied Radiation Research School, Nuclear Science and Technology Research Institute in Iran. The source consists of six resin beads (0.5 mm diameter) that are sealed in a cylindrical titanium capsule of 0.7 mm internal and 0.8 mm external diameters. This work aims to evaluate the dosimetric parameters of the newly designed 125I source using experimental measurements and Monte Carlo (MC) simulations. Dosimetric characteristics (dose rate constant, radial dose function, and 2D and 1D anisotropy functions) of the IR-Seed2 were determined using experimental measurements and MC simulations following the recommendations by the Task Group 43 (TG-43U1) report of the American Association of Physicists in Medicine (AAPM). MC simulations were performed using the MCNP5 code in water and Plexiglas, and experimental measurements were carried out using thermoluminescent dosimeters (TLD-GR207A) in Plexiglas phantoms. The measured dose to water in Plexiglas data were used for verification of the accuracy of the source and phantom geometry in the Monte Carlo simulations. The final MC simulated data to water in water were recommended for clinical applications. The MC calculated dose rate constant (Λ) of the IR-Seed2 125I seed in water was found to be 0.992 ± 0.025 cGy h-1U-1. Additionally, its radial dose function by line and point source approximations, gL(r) and gp(r), calculated for distances from 0.1 cm to 7 cm. The values of gL(r) at radial distances from 0.5 cm to 5 cm were measured in a Plexiglas phantom to be between 1.212 and 0.413. The calculated and measured of values for 2D anisotropy function, F(r, θ), were obtained for the radial distances ranging from 1.5 cm to 5 cm and angular range of 0°-90° in a Plexiglas phantom. Also, the 2D anisotropy function was calculated in water for the clinical application. The results of these investigations show that the uncertainty of

  9. Evaluation of material heterogeneity dosimetric effects using radiochromic film for COMS eye plaques loaded with {sup 125}I seeds (model I25.S16)

    SciTech Connect

    Acar, Hilal; Chiu-Tsao, Sou-Tung; Oezbay, Ismail; Kemikler, Goenuel; Tuncer, Samuray

    2013-01-15

    Purpose: (1) To measure absolute dose distributions in eye phantom for COMS eye plaques with {sup 125}I seeds (model I25.S16) using radiochromic EBT film dosimetry. (2) To determine the dose correction function for calculations involving the TG-43 formalism to account for the presence of the COMS eye plaque using Monte Carlo (MC) method specific to this seed model. (3) To test the heterogeneous dose calculation accuracy of the new version of Plaque Simulator (v5.3.9) against the EBT film data for this seed model. Methods: Using EBT film, absolute doses were measured for {sup 125}I seeds (model I25.S16) in COMS eye plaques (1) along the plaque's central axis for (a) uniformly loaded plaques (14-20 mm in diameter) and (b) a 20 mm plaque with single seed, and (2) in off-axis direction at depths of 5 and 12 mm for all four plaque sizes. The EBT film calibration was performed at {sup 125}I photon energy. MC calculations using MCNP5 code for a single seed at the center of a 20 mm plaque in homogeneous water and polystyrene medium were performed. The heterogeneity dose correction function was determined from the MC calculations. These function values at various depths were entered into PS software (v5.3.9) to calculate the heterogeneous dose distributions for the uniformly loaded plaques (of all four sizes). The dose distributions with homogeneous water assumptions were also calculated using PS for comparison. The EBT film measured absolute dose rate values (film) were compared with those calculated using PS with homogeneous assumption (PS Homo) and heterogeneity correction (PS Hetero). The values of dose ratio (film/PS Homo) and (film/PS Hetero) were obtained. Results: The central axis depth dose rate values for a single seed in 20 mm plaque measured using EBT film and calculated with MCNP5 code (both in ploystyrene phantom) were compared, and agreement within 9% was found. The dose ratio (film/PS Homo) values were substantially lower than unity (mostly between 0.8 and 0

  10. Autoradiographic localization and characterization of [125I]lysergic acid diethylamide binding to serotonin receptors in Aplysia.

    PubMed

    Kadan, M J; Hartig, P R

    1988-03-01

    The sensitive serotonergic radioligand 2-[125I]lysergic acid diethylamide was used to study the distribution and pharmacological binding properties of serotonin receptors in Aplysia californica. The high specific activity of this radioligand allowed us to develop a methodology for the investigation of receptor binding properties and receptor distribution in a single ganglion. [125I]Lysergic acid diethylamide labels a population of high-affinity serotonergic sites (Kd = 0.41 nM) in Aplysia ganglia whose regional distribution matches that expected from previous electrophysiological and immunohistochemical studies. The properties of [125I]lysergic acid diethylamide binding sites in Aplysia are in general agreement with previous studies on [3H]lysergic acid diethylamide binding in this system but these sites differ from the serotonergic receptor subtypes described in the mammalian brain. Guanine nucleotides were shown to modulate agonist but not antagonist affinity for the [125I]lysergic acid diethylamide binding site in Aplysia, suggesting that this site is coupled to a G-protein. Images of serotonin receptor distribution in the Aplysia nervous system were obtained from autoradiograms of [125I]lysergic acid diethylamide binding. Serotonin receptors in ganglia tissue sections are located primarily within the neuropil. In addition, a subset of neuronal soma are specifically labeled by [125I]lysergic acid diethylamide. These studies indicate that [125I]lysergic acid diethylamide binds to sites in the Aplysia nervous system which display a regional distribution, pharmacological binding properties and evidence of coupling to a G-protein consistent with labeling of a subset of functional serotonin receptors. In addition, the techniques used in this investigation provide a general approach for rapidly characterizing the pharmacological properties and anatomical distribution of receptor binding sites in single invertebrate ganglia. Individual neurons containing these receptor

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

    SciTech Connect

    Schulz, D.W.; Loring, R.H.; Aizenman, E.; Zigmond, R.E. )

    1991-01-01

    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.

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

    SciTech Connect

    Szigethy, E.; Quirion, R.; Beaudet, A. )

    1990-07-22

    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.

  13. Autoradiographic localization of binding sites for 2-[125I]iodomelatonin in the pars tuberalis of the western spotted skunk (Spilogale putorius latifrons).

    PubMed

    Duncan, M J; Mead, R A

    1992-01-01

    Pineal melatonin secretion mediates photoperiodic regulation of implantation of blastocysts in the female western spotted skunk. Autoradiography studies demonstrated that high affinity 2-[125I]iodomelatonin binding sites are present in the pars tuberalis but not in any other hypophyseal region or in the hypothalamus or thalamus of this species. This restricted localization of 2-[125I]iodomelatonin binding, which was characteristic of spotted skunks sacrificed at various times during their annual reproductive cycles, suggests that the pars tuberalis mediates photoperiodic responses in this species.

  14. Assaying multiple 125I seeds with the well-ionization chamber SourceCheck4π 33005 and a new insert

    PubMed Central

    Ballester, Facundo; Perez-Calatayud, Jose; Vijande, Javier

    2015-01-01

    Purpose To provide a practical solution that can be adopted in clinical routine to fulfill the AAPM-ESTRO recommendations regarding quality assurance of seeds used in prostate permanent brachytherapy. The aim is to design a new insert for the well-ionization chamber SourceCheck4π 33005 (PTW, Germany) that allows evaluating the mean air-kerma strength of up to ten 125I seeds with one single measurement instead of measuring each seed individually. Material and methods The material required is: a) the SourceCheck4π 33005 well-ionization chamber provided with a PTW insert to measure the air-kerma strength S K of one single seed at a time; b) a newly designed insert that accommodates ten seeds in one column, which allows measuring the mean S K of the ten seeds in one single measurement; and c) a container with ten seeds from the same batch and class of the seeds used for the patient implant, and a set of nine non-radioactive seeds. The new insert is characterized by determining its calibration coefficient, used to convert the reading of the well-chamber when ten seeds are measured to their mean S K. The proposed method is validated by comparing the mean S K of the ten seeds obtained from the new insert with the individual measurement of S K of each seed, evaluated with the PTW insert. Results The ratio between the calibration coefficient of the new insert and the calibration coefficient of the PTW insert for the SourceCheck4π 33005 is 1.135 ± 0.007 (k = 1). The mean S K of a set of ten seeds evaluated with this new system is in agreement with the mean value obtained from measuring independently the S K of each seed. Conclusions The new insert and procedure allow evaluating the mean S K of ten seeds prior to the implant in a single measurement. The method is faster and more efficient from radiation protection point of view than measuring the individual S K of each seed. PMID:26816507

  15. A modern Monte Carlo investigation of the TG-43 dosimetry parameters for an {sup 125}I seed already having AAPM consensus data

    SciTech Connect

    Aryal, Prakash; Molloy, Janelle A.; Rivard, Mark J.

    2014-02-15

    Purpose: To investigate potential causes for differences in TG-43 brachytherapy dosimetry parameters in the existent literature for the model IAI-125A{sup 125}I seed and to propose new standard dosimetry parameters. Methods: The MCNP5 code was used for Monte Carlo (MC) simulations. Sensitivity of dose distributions, and subsequently TG-43 dosimetry parameters, was explored to reproduce historical methods upon which American Association of Physicists in Medicine (AAPM) consensus data are based. Twelve simulation conditions varying{sup 125}I coating thickness, coating mass density, photon interaction cross-section library, and photon emission spectrum were examined. Results: Varying{sup 125}I coating thickness, coating mass density, photon cross-section library, and photon emission spectrum for the model IAI-125A seed changed the dose-rate constant by up to 0.9%, about 1%, about 3%, and 3%, respectively, in comparison to the proposed standard value of 0.922 cGy h{sup −1} U{sup −1}. The dose-rate constant values by Solberg et al. [“Dosimetric parameters of three new solid core {sup 125}I brachytherapy sources,” J. Appl. Clin. Med. Phys. 3, 119–134 (2002)], Meigooni et al. [“Experimental and theoretical determination of dosimetric characteristics of IsoAid ADVANTAGE™ {sup 125}I brachytherapy source,” Med. Phys. 29, 2152–2158 (2002)], and Taylor and Rogers [“An EGSnrc Monte Carlo-calculated database of TG-43 parameters,” Med. Phys. 35, 4228–4241 (2008)] for the model IAI-125A seed and Kennedy et al. [“Experimental and Monte Carlo determination of the TG-43 dosimetric parameters for the model 9011 THINSeed™ brachytherapy source,” Med. Phys. 37, 1681–1688 (2010)] for the model 6711 seed were +4.3% (0.962 cGy h{sup −1} U{sup −1}), +6.2% (0.98 cGy h{sup −1} U{sup −1}), +0.3% (0.925 cGy h{sup −1} U{sup −1}), and −0.2% (0.921 cGy h{sup −1} U{sup −1}), respectively, in comparison to the proposed standard

  16. Biological effects of (125)i seeds radiation on A549 lung cancer cells: G2/M arrest and enhanced cell death.

    PubMed

    Qu, Ang; Wang, Hao; Li, Jinna; Wang, Junjie; Liu, Jingjia; Hou, Yuzhu; Huang, Li; Zhao, Yong

    2014-07-01

    External beam radiation (EBRT) and (125)I seeds continuous low dose rate radiation (CLDR) were used to treat patients with lung cancer. We herein investigated the biological effects of EBRT and CLDR on lung cancer cells. A549 human lung cancer cell line was thus exposed to different doses of EBRT and CLDR. CLDR was more efficient to inhibit cell growth than EBRT. CLDR induced increased DNA damage as evidenced by long-lasting p-H2AX activity. The enhanced inhibitory effects of CLDR on lung cancer cell growth may be, at least in part, due to the increased Bax/Bcl2 ratio and cyclin B1-mediated G2/M arrest.

  17. Preparation of (125)I-ricin suitable as a probe for the autoradiographic localization of toxin binding sites

    SciTech Connect

    Doebler, J.A.; Mayer, T.W.; Traub, R.K.; Broomfield, C.A.; Calamaio, C.A.

    1993-05-13

    The long term objectives of this research are to identify cellular binding sites for ricin and examine its organ distribution in mice following aerosol inhalation exposure. Preliminary studies relating to the synthesis and evaluation of (125 I)-ricin as an autoradiographic probe have been conducted. Non-radioactive (I)-ricin prepared using the Iodogen method was found to be non-toxic both in vivo and in vitro. Lactose was then added to the Iodogen reaction medium to block galactose-binding site associated tyrosines in an attempt to retain toxicity. However, this did not prevent iodination-induced loss of biological potency. We then switched to the lactoperoxidase method of iodination, which yielded an (I)-ricin preparation with toxicity comparable to that of native toxin.

  18. Quantitative autoradiographic localization of cholecystokinin receptors in rat and guinea pig brain using sup 125 I-Bolton-Hunter-CCK8

    SciTech Connect

    Niehoff, D.L. )

    1989-03-01

    The autoradiographic localization of receptors for the brain-gut peptide cholecystokinin (CCK) has shown differences in receptor distribution between rat and guinea pig brain. However the full anatomical extent of the differences has not been determined quantitatively. In the present study, {sup 125}I-Bolton-Hunter-CCK8 ({sup 125}I-BH-CCK8) was employed in a comparative quantitative autoradiographic analysis of the distribution of CCK receptors in these two species. The pharmacological profile of {sup 125}I-BH-CCK8 binding in guinea pig forebrain sections was comparable to those previously reported for rat and human. Statistically significant differences in receptor binding between rat and guinea pig occurred in olfactory bulb, caudate-putamen, amygdala, several cortical areas, ventromedial hypothalamus, cerebellum, and a number of midbrain and brainstem nuclei. The results of this study confirm the presence of extensive species-specific variation in the distribution of CCK receptors, suggesting possible differences in the physiological roles of this peptide in different mammalian species.

  19. Autoradiographic detection of (/sup 125/I)-secondary antiserum: a sensitive light and electron microscopic labeling method compatible with peroxidase immunocytochemistry for dual localization of neuronal antigens

    SciTech Connect

    Pickel, V.M.; Chan, J.; Milner, T.A.

    1986-06-01

    We examined whether autoradiographic localization of (/sup 125/I)-antirabbit immunoglobulin (IgG) was suitable for light and electron microscopic detection of a rabbit antiserum to the catecholamine-synthesizing enzyme, tyrosine hydroxylase (TH), and whether autoradiographic and peroxidase labeling could be combined for simultaneous immunocytochemical identification of TH and neuropeptides in brain. Adult rat brains were fixed by aortic arch perfusion with acrolein and paraformaldehyde. Vibratome sections of the fixed tissues were incubated with various dilutions of TH antiserum followed by (/sup 125/I)-secondary IgG. These sections were then directly processed for autoradiography or were incubated with rabbit antiserum to substance P (SP) or methionine (Met5)-enkephalin (ME). These latter sections were then processed by the peroxidase-antiperoxidase (PAP) or conjugated peroxidase methods followed by autoradiography. Exposure periods of 12-20 days for light microscopy or 90 days for electron microscopy yielded substantial accumulations of silver grains even at the highest (1:30,000) dilution of TH antiserum. At this dilution, immunoreactivity for TH was virtually nondetectable by PAP and conjugated peroxidase methods. The differential sensitivities of the autoradiographic versus peroxidase methods provided a means for separable identification of rabbit antiserum to TH and to SP or ME. Ultrastructural analysis of the catecholaminergic neurons in the medial nuclei of the solitary tract (NTS) showed selective cytoplasmic localization of silver grains for (/sup 125/I)-labeling of TH in perikarya, dendrites, and terminals. Within single thin sections prepared for dual labeling, the peroxidase marker for SP and for ME was differentially localized with respect to autoradiographic labeling of TH.

  20. Localization of [3H]nicotine, [3H]cytisine, [3H]epibatidine, and [125I]alpha-bungarotoxin binding sites in the brain of Macaca mulatta.

    PubMed

    Han, Zhi-Yan; Zoli, Michele; Cardona, Ana; Bourgeois, Jean-Pierre; Changeux, Jean-Pierre; Le Novère, Nicolas

    2003-06-16

    We determined the localization of [(3)H]nicotine, [(3)H]cytisine, [(3)H]epibatidine, and [(125)I]alpha-bungarotoxin binding sites in the brain of rhesus monkey by means of receptor autoradiography. The labelings by [(3)H]nicotine, [(3)H]cytisine, and [(3)H]epibatidine were highly concordant, except for epibatidine. Layer IV of some cortical areas, most thalamic nuclei, and presubiculum displayed high levels of labeling for the three ligands. Moderate levels of binding were detected in the subiculum, the septum, and the mesencephalon. Low levels were present in layers I-II and VI of the cortex, the cornu Ammonis, the dentate gyrus, and the amygdala. In addition, the level of epibatidine labeling was very high in the epithalamic nuclei and the interpeduncular nucleus, whereas labeling by nicotine and cytisine was very weak in the same regions. The distribution of [(125)I]alpha-bungarotoxin binding differed from the binding of the three agonists. The labeling was dense in layer I of most cortical areas, dentate gyrus, stratum lacunosum-moleculare of CA1 field, several thalamic nuclei, and medial habenula. A moderate labeling was found in layers V and VI of the prefrontal and frontal cortices, layer IV of primary visual cortex, amygdala, septum, hypothalamus, and some mesencenphalic nuclei. A weak signal was also detected in subiculum, claustrum, stratum oriens, and stratum lucidum of cornu Ammonis and also in some mesencephalic nuclei. The distribution of nicotine, cytisine, and epibatidine bindings corresponds broadly to the patterns observed in rodents, with the marked exception of the epithalamus. However, in monkey, those distributions match the distribution of alpha2 messenger RNA, rather than that of alpha4 transcripts as it exists in rodent brains. The distribution of the binding sites for alpha-bungarotoxin is larger in the brain of rhesus monkeys than in rodent brain, suggesting a more important role of alpha7 receptors in primates.

  1. Autoradiographic localization of supraspinal kappa-opioid receptors with (/sup 125/I-Tyr1, D-Pro10)dynorphin A-(1-11)

    SciTech Connect

    Jomary, C.; Gairin, J.E.; Cros, J.; Meunier, J.C.

    1988-01-01

    (/sup 125/I-Tyr1, D-Pro10)dynorphin A-(1-11) (/sup 125/I-DP-DYN), an opioid peptide analogue that has previously been shown to be kappa selective, displays specific, saturable, and high-affinity (Kd = 0.3 nM) binding in slide-mounted sections from nerve tissue. We have used /sup 125/I-DPDYN to autoradiographically visualize supraspinal kappa-opioid receptor sites in rats, guinea pigs, and rabbits. The autoradiographic dispositions of /sup 125/I-DPDYN in sections from cerebellum are clearly different in guinea pig and rabbit, suggesting that kappa receptors have different functions in this organ of the two species. Autoradiograms from /sup 125/I-DPDYN-labeled brain sections also reveal major species differences, in particular in thalamus, which is densely labeled in rabbit and considerably less so in rat and guinea pig. The data show that /sup 125/I-DPDYN is a useful probe to visualize kappa-opioid receptor sites in nerve tissue sections directly and rapidly.

  2. Direct determination of the absorbed dose to water from 125I low dose-rate brachytherapy seeds using the new absorbed dose primary standard developed at ENEA-INMRI

    NASA Astrophysics Data System (ADS)

    Toni, M. P.; Pimpinella, M.; Pinto, M.; Quini, M.; Cappadozzi, G.; Silvestri, C.; Bottauscio, O.

    2012-10-01

    Low-intensity radioactive sources emitting low-energy photons are used in the clinic for low dose-rate brachytherapy treatments of tumours. The dosimetry of these sources is based on reference air kerma rate measurements. The absorbed dose rate to water at the reference depth d0 = 1 cm, \\dot {D}_{w,1\\,cm} , is then obtained by a conversion procedure with a large relative standard uncertainty of about 5%. This paper describes a primary standard developed at ENEA-INMRI to directly measure \\dot {D}_{w,1\\,cm} due to LDR sources. The standard is based on a large-angle and variable-volume ionization chamber, embedded in a graphite phantom and operating under ‘wall-less air chamber’ conditions. A set of correction and conversion factors, based on experiments and Monte Carlo simulations, are determined to obtain the value of Dw,1 cm from measurements of increment of ionization current with increasing chamber volume. The relative standard uncertainty on \\dot {D}_{w,1\\,cm} is 2.6%, which is appreciably lower than the current uncertainty. Characteristics of the standard, its associated uncertainty budget, and some experimental results are given for 125I BEBIG I25.S16.C brachytherapy seeds. Finally, results of the experimental determination of the dose-rate constant Λ1 cm, traceable to the Dw,1 cm and the low-energy air kerma ENEA-INMRI standards, are given. The relative standard uncertainty on Λ1 cm is 2.9%, appreciably lower than the typical uncertainty (4.8%) of the values available in the literature.

  3. Assessing DNA structures with 125I radioprobing.

    PubMed

    Gaynutdinov, Timur I; Neumann, Ronald D; Panyutin, Igor G

    2010-01-01

    Iodine-125 radioprobing is based on incorporation of radioiodine into a defined position in a nucleic acid molecule. Decay of (125)I results in the emission of multiple, low-energy Auger electrons that, along with positively charged residual daughter nuclide, produce DNA strand breaks. The probability of such strand breaks at a given nucleotide is in inverse proportion to the distance from the (125)I atom to the sugar of that nucleotide. Therefore, conclusions can be drawn about the conformation or folding of a DNA or RNA molecule based on the distribution of (125)I decay-induced strand breaks. Here we describe in detail the application (125)I radioprobing for studying the conformation of quadruplex structures, and discuss the advantages and limitations of the method. PMID:20012420

  4. Interaction of /sup 125/I-labeled botulinum neurotoxins with nerve terminals. I. Ultrastructural autoradiographic localization and quantitation of distinct membrane acceptors for types A and B on motor nerves

    SciTech Connect

    Black, J.D.; Dolly, J.O.

    1986-01-01

    The labeling patterns produced by radioiodinated botulinum neurotoxin (/sup 125/I-BoNT) types A and B at the vertebrate neuromuscular junction were investigated using electron microscopic autoradiography. The data obtained allow the following conclusions to be made. (a) /sup 125/I-BoNT type A, applied in vivo or in vitro to mouse diaphragm or frog cutaneous pectoris muscle, interacts saturably with the motor nerve terminal only; silver grains occur on the plasma membrane, within the synaptic bouton, and in the axoplasm of the nerve trunk, suggesting internalization and retrograde intra-axonal transport of toxin or fragments thereof. (b) /sup 125/I-BoNT type B, applied in vitro to the murine neuromuscular junction, interacts likewise with the motor nerve terminal except that a lower proportion of internalized radioactivity is seen. This result is reconcilable with the similar, but not identical, pharmacological action of these toxin types. (c) The saturability of labeling in each case suggested the involvement of acceptors; on preventing the internalization step with metabolic inhibitors, their precise location became apparent. They were found on all unmyelinated areas of the nerve terminal membrane, including the preterminal axon and the synaptic bouton. (d) It is not proposed that these membrane acceptors target BoNT to the nerve terminal and mediate its delivery to an intracellular site, thus contributing to the toxin's selective inhibitory action on neurotransmitter release.

  5. More accurate fitting of {sup 125}I and {sup 103}Pd radial dose functions

    SciTech Connect

    Taylor, R. E. P.; Rogers, D. W. O.

    2008-09-15

    In this study an improved functional form for fitting the radial dose functions, g(r), of {sup 125}I and {sup 103}Pd brachytherapy seeds is presented. The new function is capable of accurately fitting radial dose functions over ranges as large as 0.05 cm{<=}r{<=}10 cm for {sup 125}I seeds and 0.10 cm{<=}r{<=}10 cm for {sup 103}Pd seeds. The average discrepancies between fit and calculated data are less than 0.5% over the full range of fit and maximum discrepancies are 2% or less. The fitting function is also capable of accounting for the sharp increase in g(r) (upturn) seen for some sources for r<0.1 cm. This upturn has previously been attributed to the breakdown of the approximation of the sources as a line, however, in this study we demonstrate that another contributing factor is the 4.5 keV characteristic x-rays emitted from the Ti seed casing. Radial dose functions are calculated for 18 {sup 125}I seeds and 9 {sup 103}Pd seeds using the EGSnrc Monte Carlo user-code BrachyDose. Fitting coefficients of the new function are tabulated for all 27 seeds. Extrapolation characteristics of the function are also investigated. The new functional form is an improvement over currently used fitting functions with its main strength being the ability to accurately fit the rapidly varying radial dose function at small distances. The new function is an excellent candidate for fitting the radial dose function of all {sup 103}Pd and {sup 125}I brachytherapy seeds and will increase the accuracy of dose distributions calculated around brachytherapy seeds using the TG-43 protocol over a wider range of data. More accurate values of g(r) for r<0.5 cm may be particularly important in the treatment of ocular melanoma.

  6. Identification of selective, high affinity [125I]-angiotensin and [125I]-bradykinin binding sites in rat intestinal epithelia.

    PubMed Central

    Cox, H. M.; Munday, K. A.; Poat, J. A.

    1986-01-01

    Specific [125I]-angiotensin II (AII) and [125I]-bradykinin (Bk) binding sites have been identified within epithelial membranes from rat jejunum and descending colon. These high affinity intestinal sites exhibited KD values of 0.64 +/- 0.16 nM for [125I]-AII and 0.69 +/- 0.13 nM for [125I]-Bk, which were similar to those for [125I]-AII (0.85 nM) and [125I]-Bk binding sites (1.03 nM) previously identified in renal cortex epithelia. Specific [125I]-AII binding capacity was only 19.77 +/- 2.74 fmol mg-1 in small intestine and 11.31 +/- 2.66 fmol mg-1 in descending colon epithelia while a larger population, 332.0 +/- 72.9 fmol-mg-1 of specific [125I]-Bk sites were identified in epithelial membranes from small intestine. Significant hydrolysis of both free [125I]-AII and [125I]-Bk was observed while membrane bound peptides remained relatively resistant to degradation. Whilst no corrections have been made to the observed values of KD and Bmax quoted above, one may assume that the calculated reductions in the free hormone concentration will result in a decrease of the KD value for both peptides. Loss of membrane bound peptide, particularly of [125I]-AII, may indicate that the calculated Bmax value is an underestimation. Despite the rapid degradation of unbound [125I]-AII and [125I]-Bk during incubations the kinetics of specific peptide binding were reversible and highly selective. The order of potency for specific [125I]-AII binding was [Sar1, Leu8]-AII greater than or equal to [Sar1, Thr8]-AII greater than or equal to AII greater than [Sar1, Ile8]-AII greater than or equal to [Des, Asp1, Ile8] AII greater than AIII. Specific [125I]-Bk binding was also highly selective, the order of potency being Phe8-Bk greater than or equal to Tyr8-Bk greater than or equal to Lys-Bk much greater than Des, Arg1-Bk. AII exhibited an IC50 of greater than 1mM for specific [125I]-Bk binding and likewise Phe8-Bk for specific [125I]-AII binding. PMID:2869810

  7. Procedures for RIA /sup 125/I waste disposal

    SciTech Connect

    Hidalgo, J.U.; Shepard, E.S.; Ball, J.M.; Colomb, K.D.

    1982-04-01

    /sup 125/I can be effectively removed from coated tubes and plastic beads used as solid-phase separators by a 50% household bleach solution. This technique enables the user to dispose of these separators into common trash.

  8. Autoradiographic localization of voltage-dependent sodium channels on the mouse neuromuscular junction using /sup 125/I-alpha scorpion toxin. I. Preferential labeling of glial cells on the presynaptic side

    SciTech Connect

    Boudier, J.L.; Jover, E.; Cau, P.

    1988-05-01

    Alpha-scorpion toxins bind specifically to the voltage-sensitive sodium channel in excitable membranes, and binding is potential-dependent. The radioiodinated toxin II from the scorpion Androctonus australis Hector (alpha ScTx) was used to localize voltage-sensitive sodium channels on the presynaptic side of mouse neuromuscular junctions (NMJ) by autoradiography using both light and electron microscopy. Silver grain localization was analyzed by the cross-fire method. At the light-microscopic level, grain density over NMJ appeared 6-8x higher than over nonjunctional muscle membrane. The specificity of labeling was verified by competition/displacement with an excess of native alpha ScTx. Labeling was also inhibited by incubation in depolarizing conditions, showing its potential-dependence. At the electron-microscopic level, analysis showed that voltage-sensitive sodium channels labeled with alpha ScTx were almost exclusively localized on membranes, as expected. Due to washout after incubation, appreciable numbers of binding sites were not found on the postsynaptic membranes. However, on the presynaptic side, alpha ScTx-labeled voltage-sensitive sodium channels were localized on the membrane of non-myelin-forming Schwann cells covering NMJ. The axonal presynaptic membrane was not labeled. These results show that voltage-sensitive sodium channels are present on glial cells in vivo, as already demonstrated in vitro. It is proposed that these glial channels could be indirectly involved in the ionic homeostasis of the axonal environment.

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

    SciTech Connect

    Schmidt, R.E.; Plurad, S.B.; Saffitz, J.E.; Grabau, G.G.; Yip, H.K.

    1985-12-01

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

  10. Near-field dosimetry of {sup 125}I sources for interstitial brachytherapy implants measured using thermoluminescent sheets

    SciTech Connect

    Iwata, Kazuro; Yue, Ning J.; Nath, Ravinder

    2004-12-01

    The dosimetric characteristics were measured for two types of {sup 125}I low-energy photon-emitting sources by using a wide and highly sensitive thermoluminescent (TL) sheet film, which was developed for two-dimensional dose distribution measurements. The TL film is made of Teflon homogeneously mixed with small powders of thermoluminescence (BaSO{sub 4}:Eu doped). Various dosimetric parameters (i.e., radial dose function, 2D and 1D anisotropy functions) of model 6711 and 6702 {sup 125}I sources were obtained at various distances from the source surfaces to 15 mm. These parameters obtained with TL sheet were compared with the data recommended in the updated AAPM TG-43 report. The radial dose functions measured with TL sheet are in agreement with those established data of model 6711 {sup 125}I seed and model 6702 {sup 125}I seed at most of the distances within 5% and 7%, respectively. All the measured anisotropy functions showed symmetry about the longitudinal source axis. The anisotropy of dose distributions was clearly present in the immediate vicinity of the source edges. The measured 2D anisotropy function values at 1 cm are in reasonably good agreement with the recommended values. The differences at two points in the 1D anisotropy functions measured with TL sheet and the established data at 1 cm from source center were 0.7% and 1.9% for model 6711 and 6702 {sup 125}I sources, respectively; the differences at 0.5 cm were 1.5% and 1.7% for model 6711 and 6702 {sup 125}I sources, respectively. The relative dosimetric characteristics in the vicinity of actual interstitial brachytherapy sources containing {sup 125}I have been experimentally determined by using the TL sheet as a 2D dosimeter.

  11. Preparation and Characterization of 125I Labeled Bovine Serum Albumin

    PubMed Central

    Ashwitha Rai, K. S.; Jyothi; Rasmi, R. R.; Sarnaik, Jayula; Kadwad, V. B.; Shenoy, K. B.; Somashekarappa, H. M.

    2015-01-01

    Bovine serum albumin is a model protein, which has been conventionally used as protein standard and in many areas of biochemistry, pharmacology and medicine. Radioiodination procedure for bovine serum albumin employing chloramine-T as an oxidant with slight modification was evaluated critically to establish the optimal conditions for the preparation of radiolabeled tracer (125I-BSA) with required specific activity without impairing the immune reactivity and biological activity. Optimized radioiodination procedure involving 10 µg of chloramine-T along with 20 µg of sodium metabisulphite with 60 seconds incubation at 2° yielded 125I-BSA with high integrity. PMID:25767326

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

    PubMed

    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

  13. Scintillation Proximity Radioimmunoassay Utilizing 125I-Labeled Ligands

    NASA Astrophysics Data System (ADS)

    Udenfriend, Sidney; Diekmann Gerber, Louise; Brink, Larry; Spector, Sydney

    1985-12-01

    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.

  14. Scintillation proximity radioimmunoassay utilizing 125I-labeled ligands

    SciTech Connect

    Udenfriend, S.; Gerber, L.D.; Brink, L.; Spector, S.

    1985-12-01

    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 /sup 125/I-labeled antigen is added it binds to the beads and, by its proximity, the emitted short-range electrons of the /sup 125/I 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.

  15. Renal catabolism of /sup 125/I-glicentin

    SciTech Connect

    Lopez-Novoa, J.M.; Santos, J.C.; Villamediana, L.M.; Garrote, F.J.; Thim, L.; Moody, A.J.; Valverde, I.

    1986-05-01

    The renal catabolism of /sup 125/I-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 /sup 125/I-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 /sup 125/I-glicentin injected into the distal tubule was recovered in the urine. In isolated kidney experiments, organ clearance rate of /sup 125/I-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.

  16. Local evolution of seed flotation in Arabidopsis.

    PubMed

    Saez-Aguayo, Susana; Rondeau-Mouro, Corinne; Macquet, Audrey; Kronholm, Ilkka; Ralet, Marie-Christine; Berger, Adeline; Sallé, Christine; Poulain, Damien; Granier, Fabienne; Botran, Lucy; Loudet, Olivier; de Meaux, Juliette; Marion-Poll, Annie; North, Helen M

    2014-03-01

    Arabidopsis seeds rapidly release hydrophilic polysaccharides from the seed coat on imbibition. These form a heavy mucilage layer around the seed that makes it sink in water. Fourteen natural Arabidopsis variants from central Asia and Scandinavia were identified with seeds that have modified mucilage release and float. Four of these have a novel mucilage phenotype with almost none of the released mucilage adhering to the seed and the absence of cellulose microfibrils. Mucilage release was modified in the variants by ten independent causal mutations in four different loci. Seven distinct mutations affected one locus, coding the MUM2 β-D-galactosidase, and represent a striking example of allelic heterogeneity. The modification of mucilage release has thus evolved a number of times independently in two restricted geographical zones. All the natural mutants identified still accumulated mucilage polysaccharides in seed coat epidermal cells. Using nuclear magnetic resonance (NMR) relaxometry their production and retention was shown to reduce water mobility into internal seed tissues during imbibition, which would help to maintain seed buoyancy. Surprisingly, despite released mucilage being an excellent hydrogel it did not increase the rate of water uptake by internal seed tissues and is more likely to play a role in retaining water around the seed. PMID:24625826

  17. Local Evolution of Seed Flotation in Arabidopsis

    PubMed Central

    Saez-Aguayo, Susana; Rondeau-Mouro, Corinne; Macquet, Audrey; Kronholm, Ilkka; Ralet, Marie-Christine; Berger, Adeline; Sallé, Christine; Poulain, Damien; Granier, Fabienne; Botran, Lucy; Loudet, Olivier; de Meaux, Juliette; Marion-Poll, Annie; North, Helen M.

    2014-01-01

    Arabidopsis seeds rapidly release hydrophilic polysaccharides from the seed coat on imbibition. These form a heavy mucilage layer around the seed that makes it sink in water. Fourteen natural Arabidopsis variants from central Asia and Scandinavia were identified with seeds that have modified mucilage release and float. Four of these have a novel mucilage phenotype with almost none of the released mucilage adhering to the seed and the absence of cellulose microfibrils. Mucilage release was modified in the variants by ten independent causal mutations in four different loci. Seven distinct mutations affected one locus, coding the MUM2 β-D-galactosidase, and represent a striking example of allelic heterogeneity. The modification of mucilage release has thus evolved a number of times independently in two restricted geographical zones. All the natural mutants identified still accumulated mucilage polysaccharides in seed coat epidermal cells. Using nuclear magnetic resonance (NMR) relaxometry their production and retention was shown to reduce water mobility into internal seed tissues during imbibition, which would help to maintain seed buoyancy. Surprisingly, despite released mucilage being an excellent hydrogel it did not increase the rate of water uptake by internal seed tissues and is more likely to play a role in retaining water around the seed. PMID:24625826

  18. Validation of K-edge 125I brachytherapy enhancement with silver compounds.

    PubMed

    Young, L A; Phillips, M H; Nelson, J A

    1999-08-01

    Brachytherapy with radioactive seeds implanted within the tumour volume has demonstrated good success rates in treating certain cancers. In an effort to improve the curative rates in cancer patients, ongoing research is being conducted to enhance the amount of radiation dose that is absorbed within the tumour volume while minimizing the dose absorbed by the surrounding normal tissue. One method for enhancing tumour dose absorption with 125I brachytherapy seeds is to increase the number of photoelectric atomic interactions within the tumour volume by introducing small quantities of a silver compound, taking advantage of the K-edge effect. Because low-energy electrons and Auger electrons are the primary sources of brachytherapy dose enhancement, acquiring accurate experimental measurements of absorbed dose increases is a major challenge. To circumvent this problem, an x ray fluorescence excitation spectroscopy dosimetry technique supplemented with clinically accepted dosimetry calculations was developed to estimate relative absorbed dose increases in a water phantom containing up to 7.5 mM of silver. Excellent agreement was observed between theoretically derived Monte Carlo dosimetric predictions and experimental measurements. These results successfully demonstrated that K-edge enhanced 125I brachytherapy is indeed possible with future development of a non-toxic silver chelate.

  19. 2( sup 125 I)Iodomelatonin binding sites in spleens of guinea pigs

    SciTech Connect

    Poon, A.M.S. ); Pang, S.F. )

    1992-01-01

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

  20. Monte Carlo dosimetry for {sup 125}I and {sup 103}Pd eye plaque brachytherapy

    SciTech Connect

    Thomson, R. M.; Taylor, R. E. P.; Rogers, D. W. O.

    2008-12-15

    A Monte Carlo study of dosimetry for eye plaque brachytherapy is performed. BrachyDose, an EGSnrc user code which makes use of Yegin's multi-geometry package, is used to fully model {sup 125}I (model 6711) and {sup 103}Pd (model 200) brachytherapy seeds and the standardized plaques of the Collaborative Ocular Melanoma Study (COMS). Three-dimensional dose distributions in the eye region are obtained. In general, dose to water is scored; however, the implications of replacing water with eye tissues are explored. The effect of the gold alloy (Modulay) backing is investigated and the dose is found to be sensitive to the elemental composition of the backing. The presence of the silicone polymer (Silastic) seed carrier results in substantial dose decreases relative to water, particularly for {sup 103}Pd. For a 20 mm plaque with a Modulay backing and Silastic insert, fully loaded with 24 seeds, the dose decrease relative to water is of the order of 14% for {sup 125}I and 20% for {sup 103}Pd at a distance of 1 cm from the inner sclera along the plaque's central axis. For the configurations of seeds used in COMS plaques, interseed attenuation is a small effect within the eye region. The introduction of an air interface results in a dose reduction in its vicinity which depends on the plaque's position within the eye and the radionuclide. Introducing bone in the eye's vicinity also causes dose reductions. The dose distributions in the eye for the two different radionuclides are compared and, for the same prescription dose, {sup 103}Pd generally offers a lower dose to critical normal structures. BrachyDose is sufficiently fast to allow full Monte Carlo dose calculations for routine clinical treatment planning.

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

    SciTech Connect

    Eade, Thomas N.; Horwitz, Eric M. Ruth, Karen; Buyyounouski, Mark K.; D'Ambrosio, David J.; Feigenberg, Steven J.; Chen, David Y.T.; Pollack, Alan

    2008-06-01

    Purpose: To compare the toxicity and biochemical outcomes of intensity-modulated radiation therapy (IMRT) and {sup 125}I transperineal permanent prostate seed implant ({sup 125}I) for patients with low-risk prostate cancer. Methods and Materials: Between 1998 and 2004, a total of 374 low-risk patients (prostate-specific antigen < 10 ng/ml, T1c-T2b, Gleason score of 6 or less, and no neoadjuvant hormones) were treated at Fox Chase Cancer Center (216 IMRT and 158 {sup 125}I patients). Median follow-up was 43 months for IMRT and 48 months for {sup 125}I. The IMRT prescription dose ranged from 74-78 Gy, and {sup 125}I prescription was 145 Gy. Acute and late gastrointestinal (GI) and genitourinary (GU) toxicity was recorded by using a modified Radiation Therapy Oncology Group scale. Freedom from biochemical failure was defined by using the Phoenix definition (prostate-specific antigen nadir + 2.0 ng/ml). Results: Patients treated by using IMRT were more likely to be older and have a higher baseline American Urological Association symptom index score, history of previous transurethral resection of the prostate, and larger prostate volumes. On multivariate analysis, IMRT was an independent predictor of lower acute and late Grade 2 or higher GU toxicity and late Grade 2 or higher GI toxicity. Three-year actuarial estimates of late Grade 2 or higher toxicity were 2.4% for GI and 3.5% for GU by using IMRT compared with 7.7% for GI and 19.2% for GU for {sup 125}I, respectively. Four-year actuarial estimates of freedom from biochemical failure were 99.5% for IMRT and 93.5% for {sup 125}I (p = 0.09). Conclusions: The IMRT and {sup 125}I produce similar outcomes, although IMRT appears to have less acute and late toxicity.

  2. Radiation complications and tumor control after {sup 125}I plaque brachytherapy for ocular melanoma

    SciTech Connect

    Jensen, Ashley W.; Petersen, Ivy A. . E-mail: petersen.ivy@mayo.edu; Kline, Robert W.; Stafford, Scott L.; Schomberg, Paula J.; Robertson, Dennis M.

    2005-09-01

    Purpose: To determine the outcome of {sup 125}I 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 {sup 125}I 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.

  3. {sup 125}I Measurements for Occupational Exposure Assessment

    SciTech Connect

    Silva, L.; Pinhao, N. R.

    2008-08-14

    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 {sup 125}I 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 {mu}Sv. 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.

  4. /sup 125/I iothalamate an ideal marker for glomerular filtration

    SciTech Connect

    Odlind, B.; Haellgren, R.S.; Sohtell, M.; Lindstroem, B.

    1985-01-01

    The triiodinated angiographic contrast medium, iothalamate (usually labelled /sup 125/I), has been used extensively as a marker for glomerular filtration. The authors have studied the renal handling of /sup 125/I 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 /sup 51/Cr-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 /sup 3/H 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.

  5. Assessment of brain muscarinic acetylcholinergic receptors in living mice using a simple probe, [125I]-4-iododexetimide and [125I]-4-iodolevetimide.

    PubMed

    Sasaki, M; Müller-Gärtner, H W; Lever, J R; Ravert, H T; Dannals, R F; Guilarte, T R; Wagner, H N

    1993-12-01

    This study describes assessment of brain muscarinic acetylcholinergic receptors in living mice using a single-crystal radiation detection system, the high-affinity antagonist [125I]-4-iododexetimide, and the inactive enantiomer [125I]-4-iodolevetimide. Kinetics of radioligand binding, as well as perturbation by atropine displacement, can be determined using this simple probe technique. PMID:8152535

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

    SciTech Connect

    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.

  7. Autoradiographic quantitation and anatomical mapping of 125I-galanin binding sites in the rat central nervous system.

    PubMed

    Melander, T; Köhler, C; Nilsson, S; Hökfelt, T; Brodin, E; Theodorsson, E; Bartfai, T

    1988-01-01

    The distribution of 125I-galanin binding sites in the rat central nervous system was studied by the use of autoradiography, and the amount of peptide bound was determined by the use of microdensitometry. The amount of 125I-galanin bound in various CNS regions ranged from non detectable to 0.40 pmol per gramme tissue at a concentration of 1.5 nM 125I-galanin. The anatomical mapping revealed high density of binding sites in the telencephalon, where labelling was seen in the entorhinal, perirhinal and piriform cortices, in most septal nuclei, in the amygdala and in the hippocampal formation. In the diencephalon binding sites were densely accumulated in the hypothalamus, including the median eminence and periventricular nucleus as well as in the dorsal and medial thalamic nuclei. In the mesencephalon binding sites were seen in many nuclei including the dorsal raphe nucleus, the periaqueductal central grey and pars compacta of the substantia nigra. The pons/medulla revealed high density of binding sites in the locus coeruleus, parabrachial nuclei and in the dorsal vagal complex, while binding in the spinal cord was seen in laminae I, II and X as well as in the intermediolateral horn. The distribution of 125I-galanin binding sites corresponded well to the localization of the peptide as revealed in several earlier immunohistochemical and radioimmunoassay studies, as well as to several previously reported effects of galanin on central autonomic functions.

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

    NASA Astrophysics Data System (ADS)

    Summers, David; Karouia, Fathi

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

  9. Localization of brachytherapy seeds in ultrasound by registration to fluoroscopy

    NASA Astrophysics Data System (ADS)

    Fallavollita, P.; KarimAghaloo, Z.; Burdette, E. C.; Song, D. Y.; Abolmaesumi, P.; Fichtinger, G.

    2010-02-01

    Motivation: In prostate brachytherapy, transrectal ultrasound (TRUS) is used to visualize the anatomy, while implanted seeds can be seen in C-arm fluoroscopy or CT. Intra-operative dosimetry optimization requires localization of the implants in TRUS relative to the anatomy. This could be achieved by registration of TRUS images and the implants reconstructed from fluoroscopy or CT. Methods: TRUS images are filtered, compounded, and registered on the reconstructed implants by using an intensity-based metric based on a 3D point-to-volume registration scheme. A phantom was implanted with 48 seeds, imaged with TRUS and CT/X-ray. Ground-truth registration was established between the two. Seeds were reconstructed from CT/X-ray. Seven TRUS filtering techniques and two image similarity metrics were analyzed as well. Results: For point-to-volume registration, noise reduction combined with beam profile filter and mean squares metrics yielded the best result: an average of 0.38 +/- 0.19 mm seed localization error relative to the ground-truth. In human patient data C-arm fluoroscopy images showed 81 radioactive seeds implanted inside the prostate. A qualitative analysis showed clinically correct agreement between the seeds visible in TRUS and reconstructed from intra-operative fluoroscopy imaging. The measured registration error compared to the manually selected seed locations by the clinician was 2.86 +/- 1.26 mm. Conclusion: Fully automated seed localization in TRUS performed excellently on ground-truth phantom, adequate in clinical data and was time efficient having an average runtime of 90 seconds.

  10. Optimization of sup 125 I ophthalmic plaque brachytherapy

    SciTech Connect

    Astrahan, M.A.; Luxton, G.; Jozsef, G.; Liggett, P.E.; Petrovich, Z. )

    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.

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

    SciTech Connect

    Siuciak, J.A.; Krause, D.N.; Dubocovich, M.L. )

    1991-09-01

    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).

  12. Synthesis of [125I]IodoDPA-713, a New Probe for Imaging Inflammation

    PubMed Central

    Wang, Haofan; Pullambhatla, Mrudula; Guilarte, Tomas R.; Mease, Ronnie C.; Pomper, Martin G.

    2009-01-01

    [125I]IodoDPA-713 [125I]1, which targets the translocator protein (TSPO, 18 KDa), was synthesized in seven steps from methyl-4-methoxybenzoate as a tool for quantification of inflammation in preclinical models. Preliminary in vitro autoradiography and in vivo small animal imaging were performed using [125I]1 in a neurotoxicant-treated rat and in a murine model of lung inflammation, respectively. The radiochemical yield of [125I]1 was 44 ± 6% with a specific radioactivity of 51.8 GBq/μmol (1,400 mCi/μmol) and > 99% radiochemical purity. Preliminary studies showed that [125I]1 demonstrated increased specific binding to TSPO in a neurotoxicant-treated rat and increased radiopharmaceutical uptake in the lungs of an experimental inflammation model of lung inflammation. Compound [125I]1 is a new, convenient probe for preclinical studies of TSPO activity. PMID:19703411

  13. Synthesis of [{sup 125}I]iodoDPA-713: A new probe for imaging inflammation

    SciTech Connect

    Wang, Haofan; Pullambhatla, Mrudula; Guilarte, Tomas R.; Mease, Ronnie C.; Pomper, Martin G.

    2009-11-06

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

  14. Differential dose contributions on total dose distribution of (125)I brachytherapy source.

    PubMed

    Camgöz, B; Yeğin, G; Kumru, M N

    2010-01-01

    This work provides an improvement of the approach using Monte Carlo simulation for the Amersham Model 6711 (125)I brachytherapy seed source, which is well known by many theoretical and experimental studies. The source which has simple geometry was researched with respect to criteria of AAPM Tg-43 Report. The approach offered by this study involves determination of differential dose contributions that come from virtual partitions of a massive radioactive element of the studied source to a total dose at analytical calculation point. Some brachytherapy seeds contain multi-radioactive elements so the dose at any point is a total of separate doses from each element. It is momentous to know well the angular and radial dose distributions around the source that is located in cancerous tissue for clinical treatments. Interior geometry of a source is effective on dose characteristics of a distribution. Dose information of inner geometrical structure of a brachytherapy source cannot be acquired by experimental methods because of limits of physical material and geometry in the healthy tissue, so Monte Carlo simulation is a required approach of the study. EGSnrc Monte Carlo simulation software was used. In the design of a simulation, the radioactive source was divided into 10 rings, partitioned but not separate from each other. All differential sources were simulated for dose calculation, and the shape of dose distribution was determined comparatively distribution of a single-complete source. In this work anisotropy function was examined also mathematically.

  15. Differential dose contributions on total dose distribution of (125)I brachytherapy source.

    PubMed

    Camgöz, B; Yeğin, G; Kumru, M N

    2010-01-01

    This work provides an improvement of the approach using Monte Carlo simulation for the Amersham Model 6711 (125)I brachytherapy seed source, which is well known by many theoretical and experimental studies. The source which has simple geometry was researched with respect to criteria of AAPM Tg-43 Report. The approach offered by this study involves determination of differential dose contributions that come from virtual partitions of a massive radioactive element of the studied source to a total dose at analytical calculation point. Some brachytherapy seeds contain multi-radioactive elements so the dose at any point is a total of separate doses from each element. It is momentous to know well the angular and radial dose distributions around the source that is located in cancerous tissue for clinical treatments. Interior geometry of a source is effective on dose characteristics of a distribution. Dose information of inner geometrical structure of a brachytherapy source cannot be acquired by experimental methods because of limits of physical material and geometry in the healthy tissue, so Monte Carlo simulation is a required approach of the study. EGSnrc Monte Carlo simulation software was used. In the design of a simulation, the radioactive source was divided into 10 rings, partitioned but not separate from each other. All differential sources were simulated for dose calculation, and the shape of dose distribution was determined comparatively distribution of a single-complete source. In this work anisotropy function was examined also mathematically. PMID:24376927

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

    PubMed Central

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

    2014-01-01

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

  17. Interaction of cultured mammalian cells with [125I] diphtheria toxin.

    PubMed Central

    Bonventre, P F; Saelinger, C B; Ivins, B; Woscinski, C; Amorini, M

    1975-01-01

    The characteristics of cell adsorption and pinocytotic uptake of diphtheria toxin by several mammalian cell types were studied. Purified toxin iodinated by a solid-state lactoperoxidase method provided preparations of high specific activity and unaltered biological activity. Dephtheria toxin-sensitive HEp-2 cells and guinea pig macrophage cultures were compared with resistant mouse L-929 cells. At 37 C the resistant cells in monolayer adsorbed and internalized [125I] toxin to a greater extent than did the HEp-2 cell cultures; no significant differences were observed at 5 C. Ammonium chloride protection levels did not alter uptake of toxin by either L-929 OR HEp-2 cells. Biological activity of the iodinated toxin, however, was negated provided the presence of ammonium chloride was maintained. The ammonium salt appears to maintain toxin in a state amenable to antitoxin neutralization. Guinea pig macrophages internalized iodinated toxin to a level 10 times greater than the established cell lines. In spite of the increased uptake of toxin by the endocytic cells, ammonium chloride prevented expression of toxicity. In an artificial system, toxin adsorbed to polystyrene latex spheres and internalized by guinea pig macrophages during phagocytosis did express biological activity. Ammonium chloride afforded some but not total protection against toxin present in the phagocytic vacuoles. The data suggest that two mechanisms of toxin uptake by susceptible cells may be operative. Toxin taken into the cell by a pinocytotic process probably is not ordinarily of physiological significance since it is usually degraded by lysosomal enzymes before it can reach cytoplasmic constituents on which it acts. When large quantities of toxin are pinocytized, toxicity may be expressed before enzymatic degradation is complete. A more specific uptake involving direct passage of the toxin through the plasma membrane may be the mechanism leading to cell death in the majority of instances. PMID

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

    SciTech Connect

    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.

  19. An (125)I-labeled octavalent peptide fluorescent nanoprobe for tumor-homing imaging in vivo.

    PubMed

    Luo, Haiming; Shi, Jiyun; Jin, Honglin; Fan, Di; Lu, Lisen; Wang, Fan; Zhang, Zhihong

    2012-06-01

    Targeting radiopeptides are promising agents for radio-theranostics. However, in vivo evaluation of their targeting specificity is often obscured by their short biologic half-lives and low binding affinities. Here, we report an approach to efficiently examine targeting radiopeptides with a new class of octavalent peptide fluorescent nanoprobe (Octa-FNP) platform, which is composed of candidate targeting peptides and a tetrameric far-red fluorescent protein (tfRFP) scaffold. To shed light on this process, (125)I-Octa-FNP, (125)I-tfRFP and (125)I-peptide were synthesized, and their targeting functionalities were compared. Both fluorescence imaging and radioactive quantification results confirmed that (125)I-Octa-FNP had a significantly higher cellular binding capability than (125)I-tfRFP. In vivo biodistribution studies show that at 6 h post-injection, (125)I-Octa-FNP had 2-fold and 30-fold higher tumor uptake than that of (125)I-tfRFP and (125)I-peptide, respectively. Moreover, γ-imaging at 24 h post-injection revealed a remarkable accumulation of (125)I-Octa-FNP in the tumor while maintaining an extremely low background contrast, which was further confirmed by immunofluorescence analysis. These data suggested that, as an engineered and multivalent platform, Octa-FNP could enhance the tumor targeting of a designed peptide and provide excellent contrast radioimaging, making it a valuable tool for the evaluation of the targeting ability of specifically designed radiopeptides for cancer theranostics.

  20. [125I]AT-1012, a New High Affinity Radioligand for the α3β4 Nicotinic Acetylcholine Receptors

    PubMed Central

    Wu, Jinhua; Perry, David C.; Bupp, James E.; Jiang, Faming; Polgar, Willma E.; Toll, Lawrence; Zaveri, Nurulain T.

    2013-01-01

    Recent genetic and pharmacological studies have implicated the α3, β4 and a5 subunits of the nicotinic acetylcholine receptor (nAChR) in dependence to nicotine and other abused drugs and nicotine withdrawal. The α3β4* nAChR subtype has been shown to co-assemble with the α5 or β3 nAChR subunits, and is found mainly in the autonomic ganglia and select brain regions. It has been difficult to study the α3β4 nAChR because there have been no selective nonpeptidic ligands available to independently examine its pharmacology. We recently reported the synthesis of a [125I]-radiolabeled analog of a high affinity, selective small-molecule α3β4 nAChR ligand, AT-1012. We report here the vitro characterization of this radioligand in receptor binding and in vitro autoradiographic studies targeting the α3β4* nAChR. Binding of [125I]AT-1012 was characterized at the rat α3β4- and α4β2 nAChR transfected into HEK cells as well as at the human α3β4α5 nAChR in HEK cells. Binding affinity of [125I]AT-1012 at the rat α3β4 nAChR was 1.4 nM, with a Bmax of 10.3 pmol/mg protein, similar to what was determined using [3H]epibatidine. Saturation isotherms suggested that [125I]AT-1012 binds to a single site on the α3β4 nAChR. Similar high binding affinity was also observed for [125I]AT-1012 at human α3β4α5 nAChR in a human α3β4aα nAChR transfected cell line. [125I]AT-1012 did not bind with high affinity to membranes from α4β2 nAChR-transfected HEK cells, and [3H]epibatidine binding studies showed that AT-1012 had over 100-fold binding selectivity for the α3β4 over α4β2 nAChR. Ki values determined for known nAChR compounds using [125I]AT-1012 as radioligand were comparable to those obtained with [3H]epibatidine. [125I]AT-1012 was also used to label the α3β4 nAChR in rat brain slices in vitro using autoradiography which showed highly localized binding of the radioligand in brain regions consistent with the discreet localization of the α3β4 nAChR. We

  1. Determination of the intrinsic energy dependence of LiF:Mg,Ti thermoluminescent dosimeters for {sup 125}I and {sup 103}Pd brachytherapy sources relative to {sup 60}Co

    SciTech Connect

    Reed, J. L. Micka, J. A.; Culberson, W. S.; DeWerd, L. A.; Rasmussen, B. E.; Davis, S. D.

    2014-12-15

    Purpose: To determine the intrinsic energy dependence of LiF:Mg,Ti thermoluminescent dosimeters (TLD-100) for {sup 125}I and {sup 103}Pd brachytherapy sources relative to {sup 60}Co. Methods: LiF:Mg,Ti TLDs were irradiated with low-energy brachytherapy sources and with a {sup 60}Co teletherapy source. The brachytherapy sources measured were the Best 2301 {sup 125}I seed, the OncoSeed 6711 {sup 125}I seed, and the Best 2335 {sup 103}Pd seed. The TLD light output per measured air-kerma strength was determined for the brachytherapy source irradiations, and the TLD light output per air kerma was determined for the {sup 60}Co irradiations. Monte Carlo (MC) simulations were used to calculate the dose-to-TLD rate per air-kerma strength for the brachytherapy source irradiations and the dose to TLD per air kerma for the {sup 60}Co irradiations. The measured and MC-calculated results for all irradiations were used to determine the TLD intrinsic energy dependence for {sup 125}I and {sup 103}Pd relative to {sup 60}Co. Results: The relative TLD intrinsic energy dependences (relative to {sup 60}Co) and associated uncertainties (k = 1) were determined to be 0.883 ± 1.3%, 0.870 ± 1.4%, and 0.871 ± 1.5% for the Best 2301 seed, OncoSeed 6711 seed, and Best 2335 seed, respectively. Conclusions: The intrinsic energy dependence of TLD-100 is dependent on photon energy, exhibiting changes of 13%–15% for {sup 125}I and {sup 103}Pd sources relative to {sup 60}Co. TLD measurements of absolute dose around {sup 125}I and {sup 103}Pd brachytherapy sources should explicitly account for the relative TLD intrinsic energy dependence in order to improve dosimetric accuracy.

  2. /sup 125/I)-(d(CH2)5, Sar7)AVP: a selective radioligand for V1 vasopressin receptors

    SciTech Connect

    Kelly, J.M.; Abrahams, J.M.; Phillips, P.A.; Mendelsohn, F.A.; Grzonka, Z.; Johnston, C.I.

    1989-01-01

    Arginine8-vasopressin (AVP) acts on vascular and hepatic V1 receptors to influence blood pressure and glycogenolysis respectively. We have radioiodinated the AVP V1 receptor antagonist, (1-(beta-mercapto-beta, beta-cyclopentamethylenepropionic-acid), 7-sarcosine, 8-arginine) vasopressin ((d(CH2)5, Sar7)AVP) and determined its receptor-binding properties in rat liver and kidney plasma membranes. The binding was of high affinity to single classes of receptors (liver: Kd = 3.0 nM and Bmax = 530 +/- 10 fmol/mg protein, kidney: Kd = 0.5 +/- 0.9 nM and Bmax = 11 +/- 8 fmol/mg protein). Competition of (125I)-(d(CH2)5, Sar7)AVP binding by unlabelled AVP analogues gave the following order of potency in both tissues, consistent with that expected for binding to a V1 receptor: (d(CH2)5, Tyr(Me)2)AVP greater than AVP greater than (d(CH2)5, D-Ile2, Ile4) AVP greater than DDAVP. No degradation of (125I)-(d(CH2)5, Sar7)AVP during incubation or storage was detected by HPLC analysis. We have used (125I)-(d(CH2)5, Sar7)AVP and in vitro autoradiography to demonstrate its use in localizing brain AVP receptors. These studies suggest that (125I)-(d(CH2)5, Sar7)AVP is a suitable selective radioligand for labelling V1 receptors and will provide a valuable tool for the study of the localization and regulation of AVP V1 receptors in tissues and in receptor isolation.

  3. Preferential reduction of binding of sup 125 I-iodopindolol to beta-1 adrenoceptors in the amygdala of rat after antidepressant treatments

    SciTech Connect

    Ordway, G.A.; Gambarana, C.; Tejani-Butt, S.M.; Areso, P.; Hauptmann, M.; Frazer, A. )

    1991-05-01

    This study utilized quantitative receptor autoradiography to examine the effects of repeated administration of antidepressants to rats on the binding of the beta adrenoceptor antagonist, {sup 125}I-iodopindolol ({sup 125}I-IPIN) to either beta-1 or beta-2 adrenoceptors in various regions of brain. Antidepressants were selected to represent various chemical and pharmacological classes including tricyclic compounds (desipramine and protriptyline), monoamine oxidase inhibitors (clorgyline, phenelzine and tranylcypromine), atypical antidepressants (mianserin and trazodone) and selective inhibitors of the uptake of serotonin (citalopram and sertraline). Additionally, rats were treated with various psychotropic drugs that lack antidepressant efficacy (cocaine, deprenyl, diazepam and haloperidol). Repeated treatment of rats with desipramine, protriptyline, clorgyline, phenelzine, tranylcypromine or mianserin reduced the binding of {sup 125}I-IPIN to beta-1 adrenoceptors in many brain areas. Only in the basolateral and lateral nuclei of the amygdala did all six of these antidepressants significantly reduce {sup 125}I-IPIN binding to beta-1 adrenoceptors. In these amygdaloid nuclei, the magnitude of the reduction in the binding of {sup 125}I-IPIN caused by each of these drugs was comparable to or greater than the reduction in binding produced in any other region of brain. Reductions of binding of {sup 125}I-IPIN after antidepressant treatments were not consistently observed in the cortex, the area of brain examined most often in homogenate binding studies. Only the monoamine oxidase inhibitors caused reductions in the binding of {sup 125}I-IPIN to beta-2 adrenoceptors, and this effect was generally localized to the amygdala and hypothalamus.

  4. Isolation of /sup 125/I-concanavalin A-labeled plasma membrane from unfertilized mouse eggs

    SciTech Connect

    Boldt, J.; Wolf, D.P.

    1987-04-01

    A procedure was developed for isolation of plasma membrane (PM) preparations from unfertilized mouse eggs. Zona-free mouse eggs prepared by the method of Boldt and Wolf (Gamete Res 13:213-222, 1986) were labeled with 125I-concanavalin A (ConA) prior to sonication and fractionation on iso-osmotic self-generated Percoll density gradients. Experiments using the ConA-specific sugar alpha-methylmannoside (alpha MM) indicated that 125I-ConA bound specifically to the egg PM. Greater than 95% of 125I-ConA binding to zona-free eggs was blocked in the presence of 0.1 M alpha MM, and incubation of eggs in alpha MM after 125I-ConA labeling caused release of 85-90% of bound label. Fractionation of 125I-ConA-labeled eggs by Percoll density gradient centrifugation yielded a single radioactive peak at density = 1.025, corresponding to egg PM material. Prolonged incubation of 125I-ConA-labeled eggs or egg sonicates prior to fractionation did not alter the location of the radioactive peak, indicating that 125I-ConA did not label other organelles. As a control, human erythrocytes were labeled with 125I-ConA and fractionated under identical experimental conditions and yielded a single radioactive peak at density (1.020) comparable to that observed for 125I-ConA-labeled eggs. These results indicate that 125I-ConA can be used as a specific marker to support PM isolation from small numbers of zona-free mouse eggs.

  5. 125I-labeled anti-bFGF monoclonal antibody inhibits growth of hepatocellular carcinoma

    PubMed Central

    Hu, Peng-Hui; Pan, Lan-Hong; Wong, Patrick Ting-Yat; Chen, Wen-Hui; Yang, Yan-Qing; Wang, Hong; Xiang, Jun-Jian; Xu, Meng

    2016-01-01

    AIM: To investigate the inhibitory efficacy of 125I-labeled anti-basic fibroblast growth factor (bFGF) monoclonal antibody (mAb) in hepatocellular carcinoma (HCC). METHODS: bFGF mAb was prepared by using the 1G9B9 hybridoma cell line with hybridization technology and extracted from ascites fluid through a Protein G Sepharose affinity column. After labeling with 125I through the chloramine-T method, bFGF mAb was further purified by a Sephadex G-25 column. Gamma radiation counter GC-1200 detected radioactivity of 125I-bFGF mAb. The murine H22 HCC xenograft model was established and randomized to interventions with control (phosphate-buffered saline), 125I-bFGF mAb, 125I plus bFGF mAb, bFGF mAb, or 125I. The ratios of tumor inhibition were then calculated. Expression of bFGF, fibroblast growth factor receptor (FGFR), platelet-derived growth factor, and vascular endothelial growth factor (VEGF) mRNA was determined by quantitative reverse transcriptase real-time polymerase chain reaction. RESULTS: The purified bFGF mAb solution was 8.145 mg/mL with a titer of 1:2560000 and was stored at -20 °C. After coupling, 125I-bFGF mAb was used at a 1: 1280000 dilution, stored at 4 °C, and its specific radioactivity was 37 MBq/mg. The corresponding tumor weight in the control, 125I, bFGF mAb, 125I plus bFGF mAb, and 125I-bFGF mAb groups was 1.88 ± 0.25, 1.625 ± 0.21, 1.5 ± 0.18, 1.41 ± 0.16, and 0.98 ± 0.11 g, respectively. The tumor inhibition ratio in the 125I, bFGF mAb, 125I plus bFGF mAb, and 125I-bFGF mAb groups was 13.6%, 20.2%, 25.1%, and 47.9%, respectively. Growth of HCC xenografts was inhibited significantly more in the 125I-bFGF mAb group than in the other groups (P < 0.05). Expression of bFGF and FGFR mRNA in the 125I-bFGF mAb group was significantly decreased in comparison with other groups (P < 0.05). Groups under interventions revealed increased expression of VEGF mRNA (except for 125I group) compared with the control group. CONCLUSION: 125I-bFGF m

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

    SciTech Connect

    Kahoun, J.R.; Ruoho, A.E. )

    1992-02-15

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

  7. Some quantitative aspects of the labelling of proteins with 125 I by the iodine monochloride method.

    PubMed

    Ceska, M; Sjödin, A V; Grossmüller, F

    1971-01-01

    The labelling of proteins by the iodine monochloride method was studied by using a mathematical model. The equations used were primarily derived from the mass law equation of the isotopic exchange reaction between [(125)I]iodide and iodine monochloride. For convenient application, all equations were programmed into a computing desk-top calculator. To support the validity of the theoretical model, a series of iodinations of insulin were performed under various labelling conditions. The results of these experiments compare well with the theoretically derived values. Deviations from the theoretical values occurring at molar ratios of [(125)I]iodide to iodine monochloride < 0.1 and > 4.0 are explained and suggestions made about how to prevent them. The mathematical model was used to simulate the isotopic exchange, and the iodination reaction under various conditions, to study (a) the influence of the amount of [(125)I]iodide on the amount of [(125)I]iodine monochloride formed, (b) the influence of the specific radioactivity of [(125)I]iodide on the amount of [(125)I]iodine monochloride formed, and (c) the influence of the specific radioactivity of [(125)I]iodide on the number of millicuries needed for labelling to a desired extent.

  8. Binding, internalization, and retrograde transport of /sup 125/I-nerve growth factor in cultured rat sympathetic neurons

    SciTech Connect

    Claude, P.; Hawrot, E.; Dunis, D.A.; Campenot, R.B.

    1982-01-01

    Sympathetic neurons internalize nerve growth factor (NGF) and transport it retrogradely to their cell bodies where it appears to serve a trophic function in maintaining neuronal survival. We have characterized the binding, internalization, and retrograde transport of /sup 125/I-NGF by cultured rat sympathetic neurons. After 3 to 4 weeks in culture, sympathetic neurons possessed approximately 2 X 10(7) specific, cell surface NGF binding sites per neuron with an apparent affinity constant of 2 to 5 X 10(9) M. The density of binding sites on the plasma membrane of the neurites approximately twice that on the plasma membrane of the cell bodies. Because of the extensive network of neuronal processes, the neurites probably account for more than 99.5% of the total binding in mature cultures. Using electron microscope autoradiography, we localized the distribution of /sup 125/I-NGF in the cell body following a 1-hr exposure to /sup 125/I-NGF. The majority of silver grains were associated with lysosomal organelles, including secondary lysosomes, residual bodies, and multivesicular bodies (MVB). The MVB were the most heavily labeled, with a labeling density (L.D.) of 21, while the lysosomes had a L.D. of 3.1. To study the retrograde transport of /sup 125/I-NGF, neurons were grown in compartmentalized culture dishes and their distal processes were exposed to /sup 125/I-NGF. Radioactive material was transported to the cell bodies at the rate of approximately 3 mm/hr. The transport mechanism was sensitive to colchicine and was saturable with respect to NGF. After 8 hr of transport, when the radioactivity in the cell bodies had reached a steady state, the label again was localized primarily to the MVB (L.D. . 16.8) and the lysosomes (L.D. . 3.8). The nuclei were not labeled significantly and had an overall L.D. of 0.47. We saw no evidence for the accumulation of NGF by the nuclear membrane, the nucleolus, or chromatin.

  9. Distribution of peripherally injected peptide YY ([125I] PYY (3-36)) and pancreatic polypeptide ([125I] hPP) in the CNS: enrichment in the area postrema.

    PubMed

    Dumont, Yvan; Moyse, Emmanuel; Fournier, Alain; Quirion, Rémi

    2007-01-01

    The mechanism by which blood-borne peptide YY (3-36) (PYY(3-36)) and pancreatic polypeptide (PP) inhibit food intake is not clear and could implicate peripheral (vagal afferent pathways) and/or central (direct action on specific brain nuclei) mechanisms. To identify the primary brain structure(s) that could be activated after a peripheral injection of neuropeptide Y-related peptides, we investigated the distribution of radioactive materials using whole body autoradiography and coronal brain sections. Rats were injected with [125I] porcine (p) PYY(3-36) (i.p., 10 microCi) and killed after 30 min, 1, 2, or 4 h. After i.p. administration, significant amounts of radioactive materials were rapidly (<30 min) detected in the blood circulation and various tissues including the kidneys, liver, lung, heart, bone marrow, gastrointestinal tract, and thyroid gland, whereas in the brain, low but significant amounts of radioactive materials were detected at the level of the area postrema. Next, we investigated the distribution of radioactive labeling in the brain after i.v. injections of [125I]pPYY(3-36) (Y2 and Y5 subtypes), [125I] human (h) PP (Y4 and Y5 receptors), and [125I][Leu(31), Pro(34)] pPYY (Y1, Y4 and Y5 classes) in the rat brain. Fifteen minutes post injection, autoradiograms revealed positive signals only in the area postrema after the injection of [125I]-hPP and [125I][Leu(31), Pro(34)]pPYY. Whereas the presence of [125I]pPYY(3-36)-related labeling was detected in the area postrema, subfornical organ, and median eminence. In all other brain structures, including all hypothalamic nuclei and other circumventricular organs, near background level signals were detected. These data suggest that the inhibition of food intake observed after peripheral injections of pPYY(3-36) and hPP could involve receptor activation preferentially located at the level of the area postrema, a structure well-known to be involved in the modulation of food intake. PMID:17952639

  10. Tissue uptake and catabolic studies of /sup 125/I SS-B (La) injected into mice

    SciTech Connect

    Schrieber, L.; Melsom, R.D.; Venables, P.J.; Maini, R.N.

    1984-04-01

    The radiolabeled soluble cellular antigen /sup 125/I SS-B (La) has a plasma half-life of 3 min following iv injection into BALB/C mice. Uptake by Kupffer cells (KC) and proximal renal tubular (PRT) cells was demonstrated by autoradiography (ARG). That trichloracetic acid (TCA)-soluble products of /sup 125/I SS-B appeared in plasma within 1 min of iv injection suggests rapid in vivo breakdown. Activated peritoneal macrophages (APM) degraded /sup 125/I SS-B in a time- and cell-dose-dependent fashion. These findings suggest that the plasma clearance and catabolism of /sup 125/I SS-B may be dependent on its interaction with phagocytic cells. This rapid antigen elimination may protect against harmful autoantibody responses.

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

    SciTech Connect

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

    1985-02-01

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

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

    SciTech Connect

    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.

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

    SciTech Connect

    Moss, A.L.

    1988-01-01

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

  14. Tritiated-nicotine and /sup 125/I-alpha-bungarotoxin-labeled nicotinic receptors in the interpeduncular nucleus of rats. I. Subnuclear distribution

    SciTech Connect

    Hamill, G.S.; Clarke, P.B.; Pert, A.; Jacobowitz, D.M.

    1986-09-15

    The distribution of nicotinic receptors within the interpeduncular nucleus (IPN) was determined in male rats following in vitro labeling with the cholinergic ligands /sup 3/H-nicotine and /sup 125/I-alpha-bungarotoxin (BTX). Autoradiographic images of two rostrocaudal levels of IPN were analyzed by computer-assisted densitometry and the optical density contributed by displaceable labeling was determined in the rostral, central, intermediate, and lateral subnuclei. /sup 3/H-nicotine labeling density within the four subnuclei differs significantly at both levels of IPN. The greatest density of labeling is localized in the rostral subnucleus, followed in order of diminishing density by the central, intermediate, and lateral subnuclei. Labeling within the rostral subnucleus is prominently localized within its central zone. In the central subnucleus, a dense concentration of binding sites is apparent in the middle region, adjacent to less dense vertically oriented columns; /sup 3/H-nicotine binding sites in the lateral subnuclei appear to be most concentrated medially, adjacent to the intermediate subnuclei. /sup 125/I-BTX labeling density within the four subnuclei also differs significantly at both levels of IPN. The greatest density of labeling is found in the rostral subnucleus, followed in order of decreasing density by the lateral, central, and intermediate subnuclei. The ovoid regions of the rostral subnucleus contain dense /sup 125/I-BTX labeling. In the lateral subnuclei, /sup 125/I-BTX binding appears to be predominantly along the lateral margins of the subnucleus. The present data indicate that the IPN contains two distinct populations of putative cholinergic nicotinic receptors identified, respectively, by /sup 3/H-nicotine and /sup 125/I-BTX labeling. Each population of labeled receptors is uniquely localized in patterns that suggest differences in density within and across subnuclei.

  15. A modified competitive inhibition radioimmunoassay for the detection of C3a. Use of 125I-C3 instead of 125I-C3a.

    PubMed

    Hack, C E; Paardekooper, J; Eerenberg, A J; Navis, G O; Nijsten, M W; Thijs, L G; Nuijens, J H

    1988-04-01

    Levels of C3a in plasma are currently measured by a competitive inhibition radioimmunoassay (RIA) in which 125I-C3a is used as a tracer. In this paper, we describe a modification of this RIA: 125I-C3 instead of 125I-C3a is used. The lower limit of detection of this modified RIA is 6 ng of C3a per ml of plasma (i.e. 0.66 nmol/l). This RIA, performed with polyclonal anti-C3a antibodies coupled to a solid phase, appeared to be 30 times more sensitive compared with an RIA in which a monoclonal antibody against C3a is used. In vitro activation of the complement system in serum by aggregated IgG, zymosan, and cobra venom factor resulted in the generation of significant amounts of C3a. Assessment of the C3a levels by the modified RIA in serial plasma samples from patients who underwent cardiopulmonary bypass, yielded results very similar to those described in the literature for the established C3a-RIA. Thus, the modified C3a-RIA offers a convenient alternative for the detection of C3a in plasma samples.

  16. E-17 alpha(/sup 125/I)iodovinylestradiol: an estrogen-receptor-seeking radiopharmaceutical

    SciTech Connect

    Hanson, R.N.; Seitz, D.E.; Botarro, J.C.

    1982-05-01

    Through the use of radioiododestannylation, the specifically labeled E-17 alpha-(/sup 125/I)iodovinylestradiol ((/sup 125/I)VE2) was synthesized rapidly and in high yield from the stable precursor E-17 alpha-tributylstannylvinylestradiol (SnVE2), and its biodistribution was determined in immature female rats. The agent accumulated in the uterus, achieving a peak uptake of 0.465% ID-kg/g at 2 hr. Uterus-to-blood ratios of 19 and 16 occurred at 1 and 2 hr, respectively, declining to 7 by 4 hr after injection. The uptake of (/sup 125/I)VE2 by the uterus at 2 hr was reduced 58--65% by pretreatment of the immature rats with estradiol (5 micrograms) or tamoxifen (100 micrograms), and compared with 16 alpha-(/sup 125/I)iodoestradiol, (/sup 125/I)VE2 showed greater uterine uptake and similar uterus-to-blood ratios. The ease of preparation of the radioligand represents an advantage over the synthetic procedures for other estrogen-receptor-seeking agents.

  17. Biodistribution and dosimetry of free 211At, 125I- and 131I- in rats.

    PubMed

    Spetz, Johan; Rudqvist, Nils; Forssell-Aronsson, Eva

    2013-11-01

    131I is widely used for therapy in the clinic and 125I and 131I, and increasingly 211At, are often used in experimental studies. It is important to know the biodistribution and dosimetry for these radionuclides to determine potential risk organs when using radiopharmaceuticals containing these radionuclides. The purpose of this study was to investigate the biodistribution of 125I-, 131I-, and free 211At in rats and to determine absorbed doses to various organs and tissues. Male Sprague Dawley rats were injected simultaneously with 0.1-0.3 MBq 125I- and 0.1-0.3 MBq 131I-, or 0.05-0.2 MBq 211At and sacrificed 1 hour to 7 days after injection. The activities and activity concentrations in organs and tissues were determined and mean absorbed doses were calculated. The biodistribution of 125I- was similar to that of 131I- but the biodistribution of free 211At was different compared to 125I- and 131I-. The activity concentration of radioiodine was higher compared with 211At in the thyroid and lower in all extrathyroidal tissues. The mean absorbed dose per unit injected activity was highest to the thyroid. 131I gave the highest absorbed dose to the thyroid, and 211At gave the highest absorbed dose to all other tissues studied. PMID:23789969

  18. Radioimmunoassay for etorphine in horses with a /sup 125/I analog of etorphine

    SciTech Connect

    Tai, C.L.; Wang, C.; Weckman, T.J.; Popot, M.A.; Woods, W.E.; Yang, J.M.; Blake, J.; Tai, H.H.; Tobin, T.

    1988-05-01

    To improve the sensitivity and specificity of screening for etorphine in horses, an /sup 125/I-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 /sup 125/I-labeled etorphine was separated by a double-antibody method that reduced interference from materials associated with equine urine. The /sup 125/I-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 /sup 125/I-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 /sup 125/I-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.

  19. Biodistribution and dosimetry of free 211At, 125I- and 131I- in rats.

    PubMed

    Spetz, Johan; Rudqvist, Nils; Forssell-Aronsson, Eva

    2013-11-01

    131I is widely used for therapy in the clinic and 125I and 131I, and increasingly 211At, are often used in experimental studies. It is important to know the biodistribution and dosimetry for these radionuclides to determine potential risk organs when using radiopharmaceuticals containing these radionuclides. The purpose of this study was to investigate the biodistribution of 125I-, 131I-, and free 211At in rats and to determine absorbed doses to various organs and tissues. Male Sprague Dawley rats were injected simultaneously with 0.1-0.3 MBq 125I- and 0.1-0.3 MBq 131I-, or 0.05-0.2 MBq 211At and sacrificed 1 hour to 7 days after injection. The activities and activity concentrations in organs and tissues were determined and mean absorbed doses were calculated. The biodistribution of 125I- was similar to that of 131I- but the biodistribution of free 211At was different compared to 125I- and 131I-. The activity concentration of radioiodine was higher compared with 211At in the thyroid and lower in all extrathyroidal tissues. The mean absorbed dose per unit injected activity was highest to the thyroid. 131I gave the highest absorbed dose to the thyroid, and 211At gave the highest absorbed dose to all other tissues studied.

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

    PubMed

    Weckesser, M; Fixmann, A; Holschbach, M; Müller-Gärtner, H W

    1998-11-01

    The distribution of nicotinic and muscarinic cholinergic receptors in the human brain in vivo has been successfully characterized using radiolabeled tracers and emission tomography. The effect of acetylcholine release into the synaptic cleft on receptor binding of these tracers has not yet been investigated. The present study examined the influence of acetylcholine on binding of 4-[125I]iododexetimide to muscarinic cholinergic receptors of porcine brain synaptosomes in vitro. 4-Iododexetimide is a subtype-unspecific muscarinic receptor antagonist with high affinity. Acetylcholine competed with 4-[125I]iododexetimide in a dose-dependent manner. A concentration of 500 microM acetylcholine inhibited 50% of total specific 4-[125I]iododexetimide binding to synaptosomes when both substances were given simultaneously. An 800 microM acetylcholine solution reduced total specific 4-[125I]iododexetimide binding by about 35%, when acetylcholine was given 60 min after incubation of synaptosomes with 4-[125I]iododexetimide. Variations in the synaptic acetylcholine concentration might influence muscarinic cholinergic receptor imaging in vivo using 4-[123I]iododexetimide. Conversely, 4-[123I]iododexetimide might be an appropriate molecule to investigate alterations of acetylcholine release into the synaptic cleft in vivo using single photon emission computed tomography. PMID:9863566

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

    SciTech Connect

    Coates, J.E.; Lam, S.F.; McGaw, W.T.

    1988-08-01

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

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

    SciTech Connect

    Maxwell, J.L.; Baynes, J.W.; Thorpe, S.R.

    1988-10-05

    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.

  3. Use of 2-(/sup 125/I)iodomelatonin to characterize melatonin binding sites in chicken retina

    SciTech Connect

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

    1987-06-01

    2-(/sup 125/I)Iodomelatonin binds with high affinity to a site possessing the pharmacological characteristics of a melatonin receptor in chicken retinal membranes. The specific binding of 2-(/sup 125/I)iodomelatonin is stable, saturable, and reversible. Saturation experiments indicated that 2-(/sup 125/I)iodomelatonin labeled a single class of sites with an affinity constant (Kd) of 434 +/- 56 pM and a total number of binding sites (Bmax) of 74.0 +/- 13.6 fmol/mg of protein. The affinity constant obtained from kinetic analysis was in close agreement with that obtained in saturation experiments. Competition experiments showed a monophasic reduction of 2-(/sup 125/I)iodomelatonin binding with a pharmacological order of indole amine affinities characteristic of a melatonin receptor: 2-iodomelatonin greater than 6-chloromelatonin greater than or equal to melatonin greater than or equal to 6,7-dichloro-2-methylmelatonin greater than 6-hydroxymelatonin greater than or equal to 6-methoxymelatonin much greater than N-acetyltryptamine greater than N-acetyl-5-hydroxytryptamine greater than 5-methoxytryptamine greater than 5-hydroxytryptamine (inactive). The affinities of these melatonin analogs in competing for 2-(/sup 125/I)iodomelatonin binding sites were correlated closely with their potencies for inhibition of the calcium-dependent release of (3H)dopamine from chicken and rabbit retinas, indicating association of the binding site with a functional response regulated by melatonin. The results indicate that 2-(/sup 125/I)iodomelatonin is a selective, high-affinity radioligand for the identification and characterization of melatonin receptor sites.

  4. Fast radioactive seed localization in intraoperative cone beam CT for low-dose-rate prostate brachytherapy

    NASA Astrophysics Data System (ADS)

    Hu, Yu-chi; Xiong, Jian-ping; Cohan, Gilad; Zaider, Marco; Mageras, Gig; Zelefsky, Michael

    2013-03-01

    A fast knowledge-based radioactive seed localization method for brachytherapy was developed to automatically localize radioactive seeds in an intraoperative volumetric cone beam CT (CBCT) so that corrections, if needed, can be made during prostate implant surgery. A transrectal ultrasound (TRUS) scan is acquired for intraoperative treatment planning. Planned seed positions are transferred to intraoperative CBCT following TRUS-to-CBCT registration using a reference CBCT scan of the TRUS probe as a template, in which the probe and its external fiducial markers are pre-segmented and their positions in TRUS are known. The transferred planned seeds and probe serve as an atlas to reduce the search space in CBCT. Candidate seed voxels are identified based on image intensity. Regions are grown from candidate voxels and overlay regions are merged. Region volume and intensity variance is checked against known seed volume and intensity profile. Regions meeting the above criteria are flagged as detected seeds; otherwise they are flagged as likely seeds and sorted by a score that is based on volume, intensity profile and distance to the closest planned seed. A graphical interface allows users to review and accept or reject likely seeds. Likely seeds with approximately twice the seed volume are automatically split. Five clinical cases are tested. Without any manual correction in seed detection, the method performed the localization in 5 seconds (excluding registration time) for a CBCT scan with 512×512×192 voxels. The average precision rate per case is 99% and the recall rate is 96% for a total of 416 seeds. All false negative seeds are found with 15 in likely seeds and 1 included in a detected seed. With the new method, updating of calculations of dose distribution during the procedure is possible and thus facilitating evaluation and improvement of treatment quality.

  5. Increased /sup 125/I-labelled concanavalin A binding to erythrocytes in diabetes mellitus

    SciTech Connect

    Okada, Y.; Arima, T.; Okazaki, S.; Nakata, K.; Nagashima, H.; Yamabuki, T.

    1982-03-01

    Percentage binding of /sup 125/I-labelled concanavalin A to erythrocytes in diabetic patients was significantly higher than that in normal subjects (12.2 +- 2.8 versus 8.1 +- 1.8%, mean +- SD, p < 0.001). Insulin-dependent diabetic patients showed significantly higher concanavalin A binding than non-insulin-dependent diabetic subjects (15.0 +- 1.4 versus 11.4 +- 2.5%, p < 0.01). There was a highly significant correlation between percentage binding of /sup 125/I-labelled concanavalin A and glycosylated haemoglobin.

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

    SciTech Connect

    Gerhardt, M.A.; Wade, S.M.; Neubig, R.R. )

    1990-08-01

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

  7. 2-([sup 125]I) iodomelatonin binding sites in rat adrenals: Pharmacological characteristics and subcellular distribution

    SciTech Connect

    Persengiev, S.P. )

    1992-01-01

    Specific binding sites for 2-[[sup 125]I] iodomelatonin, a selective radiolabeled melatonin receptor ligand, were detected and characterized in rat adrenal membranes. Saturation studies demonstrated that 2-[[sup 125]I]iodomelatonin binds to a single class of sites with an affinity constant (Kd) of 541 pM and a total binding capacity (Bmax) of 3.23 fmol/mg protein. Competition experiments revealed that the relative order of potency of compounds tested was as follows: 6-chloromelatonin > 2-iodomelatonin > melatonin > 5-methoxytryptamine > 5-methoxytryptophol. The highest density of binding sites was found in membranes from nuclear and mitochondrial subcellular fractions.

  8. Photolabeling of membrane-bound Torpedo nicotinic acetylcholine receptor with the hydrophobic probe 3-trifluoromethyl-3-(m-(/sup 125/I)iodophenyl)diazirine

    SciTech Connect

    White, B.J.; Cohen, J.B.

    1988-11-29

    The hydrophobic, photoactivatable probe 3-trifluoromethyl-3-(m-(/sup 125/I)iodophenyl)diazirine ((/sup 125/I)TID) was used to label acetylcholine receptor rich membranes purified from Torpedo californica electric organ. All four subunits of the acetylcholine receptor (AChR) were found to incorporate label, with the ..gamma..-subunit incorporating approximately 4 times as much as each of the other subunits. Carbamylcholine, an agonist, and histrionicotoxin, a noncompetitive antagonist, both strongly inhibited labeling of all AChR subunits in a specific and dose-dependent manner. In contrast, the competitive antagonist ..cap alpha..-bungarotoxin and the noncompetitive antagonist phencyclidine had only modest effect on (/sup 125/I)TID labeling of the AChR. The regions of the AChR ..cap alpha..-subunit that incorporate (/sup 125/)TID were mapped by Staphylococcus aureus V8 protest digestion. The carbamylcholine-sensitive site of labeling was localized to a 20-kDa V8 cleavage fragment that begins at Ser-173 and is of sufficient length to contain the three hydrophobic regions M1, M2, and M3. A 10-kDa fragment beginning at Asn-339 and containing the hydrophobic region M4 also incorporated (/sup 125/I)TID but in a carbamylcholine-insensitive manner. Two further cleavage fragments, which together span about one-third of the ..cap alpha..-subunit amino terminus, incorporated no detectable (/sup 125/I)TID. The mapping results place constraints on suggested models of AChR subunit topology.

  9. CT, MR, and ultrasound image artifacts from prostate brachytherapy seed implants: The impact of seed size

    SciTech Connect

    Robertson, Andrew K. H.; Basran, Parminder S.; Thomas, Steven D.; Wells, Derek

    2012-04-15

    Purpose: To investigate the effects of brachytherapy seed size on the quality of x-ray computed tomography (CT), ultrasound (US), and magnetic resonance (MR) images and seed localization through comparison of the 6711 and 9011 {sup 125}I sources. Methods: For CT images, an acrylic phantom mimicking a clinical implantation plan and embedded with low contrast regions of interest (ROIs) was designed for both the 0.774 mm diameter 6711 (standard) and the 0.508 mm diameter 9011 (thin) seed models (Oncura, Inc., and GE Healthcare, Arlington Heights, IL). Image quality metrics were assessed using the standard deviation of ROIs between the seeds and the contrast to noise ratio (CNR) within the low contrast ROIs. For US images, water phantoms with both single and multiseed arrangements were constructed for both seed sizes. For MR images, both seeds were implanted into a porcine gel and imaged with pelvic imaging protocols. The standard deviation of ROIs and CNR values were used as metrics of artifact quantification. Seed localization within the CT images was assessed using the automated seed finder in a commercial brachytherapy treatment planning system. The number of erroneous seed placements and the average and maximum error in seed placements were recorded as metrics of the localization accuracy. Results: With the thin seeds, CT image noise was reduced from 48.5 {+-} 0.2 to 32.0 {+-} 0.2 HU and CNR improved by a median value of 74% when compared with the standard seeds. Ultrasound image noise was measured at 50.3 {+-} 17.1 dB for the thin seed images and 50.0 {+-} 19.8 dB for the standard seed images, and artifacts directly behind the seeds were smaller and less prominent with the thin seed model. For MR images, CNR of the standard seeds reduced on average 17% when using the thin seeds for all different imaging sequences and seed orientations, but these differences are not appreciable. Automated seed localization required an average ({+-}SD) of 7.0 {+-} 3.5 manual

  10. Localisation of /sup 125/I-labelled streptolysin O of Streptococcus pyogenes in mice

    SciTech Connect

    Shibl, A.M.; Abdullah, M.E.; Al-Sowaygh, I.A.

    1981-01-01

    The fate of /sup 125/I-labelled Streptolysin O injected intravenously into mice was studied. After 2 hours only 5% of the injected label remained in the blood. The highest concentration of radioactivity was consistently observed in the liver and kidneys. The labelled toxin was degraded in the liver but its greatest toxic effect took place in the kidneys.

  11. Human platelet ( sup 125 I)R-DOI binding sites. Characterization by in vitro autoradiography

    SciTech Connect

    Himeno, A.; Saavedra, J.M. )

    1990-02-01

    We quantified binding sites for 2,5-dimethoxy-4-iodo-phenylisopropylamine (DOI), a 5-HT2 agonist and hallucinogen, in human platelets. We incubated sections from human platelet pellets with ({sup 125}I)R-DOI with or without 1 mumol/L ketanserin, followed by autoradiography and computerized microdensitometry. We corrected the values of binding density by the protein content of each section with a densitometric protein assay. The present method revealed a single class of high affinity binding sites for ({sup 125}I)R-DOI, with a Kd of 6.4 +/- 0.7 nmol/L and a Bmax of 100 +/- 10 fmol/mg protein. Kd and Bmax for ({sup 125}I)R-DOI determined by the classical membrane binding assay, were 2.7 +/- 0.4 nmol/L and 100 +/- 10 fmol/mg protein, respectively. The present method is precise, very sensitive, and allows the characterization of ({sup 125}I)R-DOI binding in sections obtained from as little as 3 ml of blood. Standardization is possible after correction by the protein content of each individual section.

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

    SciTech Connect

    Grigoriadis, D.E.; Wilson, A.A.; Lew, R.; Sharkey, J.S.; Kuhar, M.J. )

    1989-08-01

    The dopamine transporter was labeled using a photosensitive compound related to GBR-12909, {sup 125}I-1-(2-(diphenylmethoxy)ethyl)-4-(2- (4-azido-3-iodophenyl)ethyl)piperazine ({sup 125}I-DEEP). {sup 125}I-DEEP bound reversibly and with high affinity to the dopamine transport protein in the absence of light and could be covalently attached to the protein following exposure to UV light. In rat striatal homogenates, {sup 125}I-DEEP was found to incorporate covalently into a protein with apparent molecular weight of 58,000 Da. The properties of this binding protein were characteristic of the dopamine transporter since covalent attachment could be inhibited by dopamine-uptake blockers with the proper pharmacological rank order of potencies. Covalent binding was also inhibited in a stereospecific manner by (+) and (-) cocaine, as well as other cocaine analogs. The protein was not found in the cerebellum. The dopamine transporter appears to exist in a glycosylated form since photoaffinity-labeled transport sites could adsorb to wheat germ-agglutinin and could be specifically eluted from the column by beta-N-acetylglucosamine.

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

    PubMed

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

    1993-06-01

    1. The characteristics of a propranolol-resistant (-)-[125I]-cyanopindolol (CYP) binding site in rat soleus muscle were determined. 2. Saturation studies performed on homogenates of rat soleus muscle showed two phases of (-)-[125I]-CYP binding, a high affinity site (KD1 30.5 +/- 16.3 pM, Bmax 9.4 +/- 1.38 fmol mg-1 protein) and a lower affinity site (KD2 522.5 +/- 29.1 pM, Bmax 62.19 +/- 11.76 fmol mg-1 protein, n = 4). 3. In rat soleus muscle homogenates labelled with (-)-[125I]-CYP (500 pM), (-)-propranolol competition curves were biphasic with pKD values of 8.30 +/- 0.19, and 5.33 +/- 0.08, n = 7. 4. Competition between (-)-[125I]-CYP (500 pM) and (+/-)-tertatolol, (+/-)-nadolol, (+/-)-alprenolol, (+/-)-CYP, and (-) and (+)-pindolol showed that these compounds competed for binding at the propranolol-resistant site with affinities lower than those displayed at typical beta-adrenoceptors. The atypical beta-adrenoceptor agonists BRL 37344, SR58611A and ICI D7114 and the partial agonist (+/-)-CGP 12177 also competed for (-)-[125I]-CYP binding. 5. Stereoselectivity was demonstrated for the stereoisomers of alprenolol and tertalolol. The (-)-isomers of alprenolol and tertalolol had higher affinity than their corresponding (+)-isomers (3.1 and 2.6 fold respectively). These low stereoselectivity values are a characteristic of atypical beta-adrenoceptors. 6. The beta-adrenoceptor agonists, (-)-adrenaline, (-)-isoprenaline and (-)-noradrenaline, all showed lower affinity than the atypical beta-adrenoceptor agonists and competition curves appeared biphasic in nature. 7. These results confirm the presence of a propranolol-resistant (- )-[125I]-CYP binding site in rat soleus muscle. The affinities of the tested compounds at the propranolol-resistant (- )-[125I]-CYP binding site show similarities to their affinities at 'atypical' beta-adrenoceptors in adipocytes and gastrointestinal tissues and at the cloned beta 3-adrenoceptor. PMID:8102926

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

    PubMed

    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

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

    PubMed Central

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

    1993-01-01

    1. The characteristics of a propranolol-resistant (-)-[125I]-cyanopindolol (CYP) binding site in rat soleus muscle were determined. 2. Saturation studies performed on homogenates of rat soleus muscle showed two phases of (-)-[125I]-CYP binding, a high affinity site (KD1 30.5 +/- 16.3 pM, Bmax 9.4 +/- 1.38 fmol mg-1 protein) and a lower affinity site (KD2 522.5 +/- 29.1 pM, Bmax 62.19 +/- 11.76 fmol mg-1 protein, n = 4). 3. In rat soleus muscle homogenates labelled with (-)-[125I]-CYP (500 pM), (-)-propranolol competition curves were biphasic with pKD values of 8.30 +/- 0.19, and 5.33 +/- 0.08, n = 7. 4. Competition between (-)-[125I]-CYP (500 pM) and (+/-)-tertatolol, (+/-)-nadolol, (+/-)-alprenolol, (+/-)-CYP, and (-) and (+)-pindolol showed that these compounds competed for binding at the propranolol-resistant site with affinities lower than those displayed at typical beta-adrenoceptors. The atypical beta-adrenoceptor agonists BRL 37344, SR58611A and ICI D7114 and the partial agonist (+/-)-CGP 12177 also competed for (-)-[125I]-CYP binding. 5. Stereoselectivity was demonstrated for the stereoisomers of alprenolol and tertalolol. The (-)-isomers of alprenolol and tertalolol had higher affinity than their corresponding (+)-isomers (3.1 and 2.6 fold respectively). These low stereoselectivity values are a characteristic of atypical beta-adrenoceptors. 6. The beta-adrenoceptor agonists, (-)-adrenaline, (-)-isoprenaline and (-)-noradrenaline, all showed lower affinity than the atypical beta-adrenoceptor agonists and competition curves appeared biphasic in nature.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:8102926

  16. Identification of beta 2-adrenoceptors on guinea pig alveolar macrophages using (-)-3-( sup 125 I)iodocyanopindolol

    SciTech Connect

    Leurs, R.; Beusenberg, F.D.; Bast, A.; Van Amsterdam, J.G.; Timmerman, H. )

    1990-08-01

    The beta-adrenoceptor antagonist (-)-3-({sup 125}I)iodocyanopindolol (({sup 125}I)ICYP) binds with high affinity and in saturable way to membranes of guinea pig alveolar macrophages. The equilibrium dissociation constant for ({sup 125}I)ICYP is 24.3 +/- 1.2 pM, and the number of binding sites is 166.3 +/- 13.7 fmol/mg protein (N = 4, +/- SEM). Displacement studies with selective antagonists showed that ({sup 125}I)ICYP labels beta 2-adrenoceptors on guinea pig alveolar macrophages.

  17. Monte Carlo dosimetry for {sup 103}Pd, {sup 125}I, and {sup 131}Cs ocular brachytherapy with various plaque models using an eye phantom

    SciTech Connect

    Lesperance, Marielle; Martinov, M.; Thomson, R. M.

    2014-03-15

    Purpose: To investigate dosimetry for ocular brachytherapy for a range of eye plaque models containing{sup 103}Pd, {sup 125}I, or {sup 131}Cs seeds with model-based dose calculations. Methods: Five representative plaque models are developed based on a literature review and are compared to the standardized COMS plaque, including plaques consisting of a stainless steel backing and acrylic insert, and gold alloy backings with: short collimating lips and acrylic insert, no lips and silicone polymer insert, no lips and a thin acrylic layer, and individual collimating slots for each seed within the backing and no insert. Monte Carlo simulations are performed using the EGSnrc user-code BrachyDose for single and multiple seed configurations for the plaques in water and within an eye model (including nonwater media). Simulations under TG-43 assumptions are also performed, i.e., with the same seed configurations in water, neglecting interseed and plaque effects. Maximum and average doses to ocular structures as well as isodose contours are compared for simulations of each radionuclide within the plaque models. Results: The presence of the plaque affects the dose distribution substantially along the plaque axis for both single seed and multiseed simulations of each plaque design in water. Of all the plaque models, the COMS plaque generally has the largest effect on the dose distribution in water along the plaque axis. Differences between doses for single and multiple seed configurations vary between plaque models and radionuclides. Collimation is most substantial for the plaque with individual collimating slots. For plaques in the full eye model, average dose in the tumor region differs from those for the TG-43 simulations by up to 10% for{sup 125}I and {sup 131}Cs, and up to 17% for {sup 103}Pd, and in the lens region by up to 29% for {sup 125}I, 34% for {sup 103}Pd, and 28% for {sup 131}Cs. For the same prescription dose to the tumor apex, the lowest doses to critical

  18. Application of 125I-labelled soluble proteins in the histoautoradiographic detection of antigen and antibodies in the spleen of rabbits during primary immune response.

    PubMed

    Rodák, L

    1975-10-01

    An autoradiographic method for detecting soluble antigen (chicken serum albumin, CSA) and specific antibodies in the spleen of rabbits during a primary immune response is described. The method consists of incubating sections from the spleen with 125I-labelled IgG2 anti CSA (for demonstration of antigen) or with 125I-labelled antigen (for demonstration of specific antibodies). This treatment of histological sections combines the advantages and principles of the immunofluorescence technique with the possibility of evaluating the exact localization of the proteins by light microscopy in preparations stained with haematoxylin or methyl green-pyronin. The sensitivity of detection is very high: both antigen and antibodies could be demonstrated in the spleen follicles for as long as 42 days after the primary intravenous injection.

  19. Automated localization of implanted seeds in 3D TRUS images used for prostate brachytherapy

    SciTech Connect

    Wei Zhouping; Gardi, Lori; Downey, Donal B.; Fenster, Aaron

    2006-07-15

    An algorithm has been developed in this paper to localize implanted radioactive seeds in 3D ultrasound images for a dynamic intraoperative brachytherapy procedure. Segmentation of the seeds is difficult, due to their small size in relatively low quality of transrectal ultrasound (TRUS) images. In this paper, intraoperative seed segmentation in 3D TRUS images is achieved by performing a subtraction of the image before the needle has been inserted, and the image after the seeds have been implanted. The seeds are searched in a 'local' space determined by the needle position and orientation information, which are obtained from a needle segmentation algorithm. To test this approach, 3D TRUS images of the agar and chicken tissue phantoms were obtained. Within these phantoms, dummy seeds were implanted. The seed locations determined by the seed segmentation algorithm were compared with those obtained from a volumetric cone-beam flat-panel micro-CT scanner and human observers. Evaluation of the algorithm showed that the rms error in determining the seed locations using the seed segmentation algorithm was 0.98 mm in agar phantoms and 1.02 mm in chicken phantoms.

  20. Increased (/sup 125/I)trypsin-binding in serum from cystic fibrosis patients

    SciTech Connect

    Cox, K.L.; Frates, R.C. Jr.; Sheikholislam, B.M.; Iwahashi-Hosoda, C.K.

    1982-01-01

    The capacities of normal and cystic fibrosis (CF) sera to bind to exogenous human (/sup 125/I)trypsin were compared. Sera from eight older CF patients bound significantly more exogenous human (/sup 125/I)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.

  1. Genesis of B lymphocytes in the bone marrow: extravascular and intravascular localization of surface IgM-bearing cells in mouse bone marrow detected by electron-microscope radioautography after in vivo perfusion of 125I anti-IgM antibody

    SciTech Connect

    Osmond, D.G.; Batten, S.J.

    1984-07-01

    The role of mammalian bone marrow in generating surface IgM (sIgM)-bearing B lymphocytes is reviewed. Precursor cells in the marrow give rise to large, rapidly dividing cells bearing free cytoplasmic mu chains (c mu). The progeny of the large c mu+ cells form a population of small, nondividing c mu+ cells that mature into small lymphocytes, progressively expressing sIgM and other B-cell surface membrane components. Newly formed sIgM+ cells soon migrate through the bloodstream to the spleen and other lymphoid tissues, where they may die after a short lifespan or be activated to produce antibody molecules. The large-scale lymphocytopoiesis in the bone marrow thus maintains a population of rapidly renewed virgin B lymphocytes in the peripheral lymphoid tissues. A technique for perfusing radiolabeled anti-IgM antibodies in young mice has now permitted sIgM+ cells to be detected radioautographically in histological preparations of bone marrow under the electron microscope. Small sIgM+ lymphocytes are situated either singly or in small groups throughout the extravascular hemopoietic compartment of the bone marrow, often near sinusoid walls adjacent to late erythroblasts and reticular cells. Some regional concentrations of sIgM+ cells are apparent. sIgM+ cells also appear in transit through the sinusoidal endothelium and are markedly concentrated in the lumen of some sinusoids. Intrasinusoidal sIgM+ small lymphocytes have high densities of sIgM and long microvilli, on which sIgM molecules are concentrated. These studies reveal the localization and cell associations of specifically identified sIgM+ small lymphocytes in the extravascular marrow compartment and suggest that these cells may also undergo a transient intravascular storage and maturation phase. Use of this in vivo immunolabeling technique to detect other cell-surface markers may further elucidate the microenvironmental basis of B lymphocyte genesis in the bone marrow.

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

    SciTech Connect

    Tilton, R.G.; Pugliese, G.; Chang, K.; Speedy, A.; Province, M.A.; Kilo, C.; Williamson, J.R.

    1989-05-01

    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.

  3. Autoradiographic evidence of sup 125 I-. beta. -endorphin binding sites in the articular cartilage of the rat

    SciTech Connect

    Castano, M.T.; Freire-Garabal, M.; Giraldez, M.; Nunez, M.J.; Belmonte, A.; Couceiro, J.; Jorge, J. )

    1991-01-01

    After {sup 125}I-{beta}-endorphin was intravenously injected to rats, an autoradiographic study of distal femur articular cartilage was performed. Results show a specific binding of {sup 125}I-{beta}-endorphin to chondrocytes, suggesting the possible existence of an opiate modulation of articular cartilage.

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

    SciTech Connect

    Evans, M.L.; Kadan, M.J.; Hartig, P.R.; Carpenter, D.O. )

    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.

  5. Glucocorticoid interactions with ethanol effects on synaptic plasma membranes: influence on [125I]calmodulin binding.

    PubMed

    Sze, P Y

    1996-02-01

    Ca(++)-dependent binding of calmodulin (CaM) to brain synaptic plasma membranes is known to be inhibited by ethanol and stimulated by glucocorticoids. These opposite neurochemical actions between ethanol and the steroids in vitro are consistent with glucocorticoid antagonism of ethanol-induced sedation reported to occur in vivo. The present study was undertaken to characterize the interactions of corticosterone with ethanol effects on [125I]CaM binding in synaptic plasma membranes. From the shift of concentration-response curves when corticosterone and ethanol were present in combination, the interaction between steroid stimulation and ethanol inhibition occurred in an additive relationship over the range of their effective concentrations. From Scatchard analyses, ethanol-induced decrease in membrane affinity for [125I]CaM was antagonized by steroid-induced increase in the membrane affinity, indicating that the convergent event in their interaction was the alteration of membrane affinity for CaM. Glucocorticoid antagonism of ethanol inhibition of [125I]CaM binding exhibited a high degree of steroid specificity; steroids with glucocorticoid activity including cortisol, dexamethasone and triamcinolone were effective, whereas gonadal steroids and excitatory neuroactive steroid metabolites were ineffective. The demonstration that glucocorticoids antagonized the inhibition of CaM binding by ethanol provides support for the hypothesis that these steroids are among the endogenous factors that modulate neuronal sensitivity to ethanol.

  6. Radioimmunoassay of progesterone in saliva: a simplified technique using /sup 125/I-radioligand

    SciTech Connect

    Tho, S.P.; Scholer, J.; Phung, B.V.; Harp, R.J.; McDonough, P.G.

    1985-03-01

    The value of serial salivary progesterone (P) determinations for evaluation of corpus luteum function compared with sporadic serum samplings is recognized. Salivary P concentrations have previously been determined by a relatively difficult assay which utilizes a tritiated radioligand. The present study was designed to compare this conventional method with a simpler assay utilizing an iodinated radioligand. The values obtained with two different radioimmunoassay (RIA) systems were compared for samples collected throughout the luteal phase of seven normal menstrual cycles and three conception cycles. In the seven nonconception luteal phases as well as in the three conception luteal phases, daily salivary P determinations by the two techniques correlated significantly with each other (r = 0.56; P less than 0.001). For the seven nonconception luteal phases, the salivary P determinations obtained by /sup 125/I RIA (Saliva /sup 125/I) correlated significantly with the matched serum values (r = 0.54; P less than 0.001). However, the correlation was poor between the salivary P determinations obtained by the /sup 3/H RIA (Saliva /sup 3/H) and the matched serum values. The simplicity and accuracy of the /sup 125/I RIA and the convenience of saliva sampling provide a practical approach to monitor human luteal function.

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

    SciTech Connect

    Hartig, P.R.; Scheffel, U., Frost, J.J.; Wagner, H.N. Jr.

    1985-08-19

    The binding of /sup 125/I-LSD (2-(/sup 125/I)-lysergic acid diethylamide) was studied in various mouse brain regions following intravenous injection of the radioligand. The high specific activity of /sup 125/I-LSD enabled the injection of low mass doses (14ng/kg), which are well below the threshold for induction of any known physiological effect of the probe. The highest levels of /sup 125/I-LSD binding were found in the frontal cortex, olfactory tubercles, extra-frontal cortex and striatum while the lowest level was found in the cerebellum. Binding was saturable in the frontal cortex but increased linearly in the cerebellum with increasing doses of /sup 125/I-LSD. Serotonergic compounds potently inhibited /sup 125/I-LSD binding in cortical regions, olfactory tubercles, and hypothalamus but had no effect in the cerebellum. Dopaminergic compounds caused partial inhibition of binding in the striatum while adrenergic compounds were inactive. From these studies the authors conclude that /sup 125/I-LSD labels serotonin 5-HT/sub 2/ receptor sites in cortical regions with no indication that other receptor sites are labeled. In the olfactory tubercles and hypothalamus, /sup 125/I-LSD labeling occurs predominantly or entirely at serotonic 5-HT/sub 2/ sites. In the striatum, /sup 125/I-LSD labels approximately equal proportions of serotonergic and dopaminergic sites. These data indicate that /sup 125/I-LSD labels serotonin receptors in vivo and suggests that appropriate derivatives of 2I-LSD may prove useful for tomographic imaging of serotonin 5-HT/sub 2/ receptors in the mammalian cortex.

  8. Embryo Localization Enhances the Survival of Acidovorax citrulli in Watermelon Seeds.

    PubMed

    Dutta, Bhabesh; Schneider, Raymond W; Robertson, Clark L; Walcott, Ronald R

    2016-04-01

    Acidovorax citrulli, the causal agent of bacterial fruit blotch (BFB) of cucurbits has been observed to survive for >34 years in stored melon and watermelon seeds. To better understand this remarkable longevity, we investigated the bacterium's tolerance to desiccation and the effect of bacterial localization in different watermelon seed tissues on its survival. We compared the ability of A. citrulli to tolerate desiccation on filter paper discs and on host (watermelon) and nonhost (cabbage, corn and tomato) seeds to two seedborne (Xanthomonas campestris pv. campestris and Pantoea stewartii subsp. stewartii) and one soilborne (Ralstonia solanacearum) plant-pathogenic bacteria. A. citrulli survival on dry filter paper (>12 weeks) was similar to that of X. campestris pv. campestris but longer than P. stewartii subsp. stewartii. Ralstonia solanacearum survived longer than all other bacteria tested. On all seeds tested, A. citrulli and X. campestris pv. campestris populations declined by 5 orders of magnitude after 12 weeks of incubation at 4°C and 50% relative humidity, while R. solanacearum populations declined by 3 orders. P. stewartii subsp. stewartii was not recovered after 12 weeks of incubation. To determine the effect of tissue localization on bacterial survival, watermelon seeds infested with A. citrulli by flower stigma inoculation (resulting in bacterial localization in the embryo/endosperm) or by ovary pericarp inoculations (resulting in bacterial localization under the testa) were treated with peroxyacetic acid or chlorine (Cl2) gas. Following these treatments, a significantly higher reduction in BFB seed-to-seedling transmission was observed for seeds generated by ovary pericarp inoculation (≥89.5%) than for those generated by stigma inoculation (≤76.5%) (P<0.05). Additionally, higher populations of A. citrulli survived when the bacteria were localized to the embryo/endosperm versus the seed coat, suggesting that tissue localization is important for

  9. Embryo Localization Enhances the Survival of Acidovorax citrulli in Watermelon Seeds.

    PubMed

    Dutta, Bhabesh; Schneider, Raymond W; Robertson, Clark L; Walcott, Ronald R

    2016-04-01

    Acidovorax citrulli, the causal agent of bacterial fruit blotch (BFB) of cucurbits has been observed to survive for >34 years in stored melon and watermelon seeds. To better understand this remarkable longevity, we investigated the bacterium's tolerance to desiccation and the effect of bacterial localization in different watermelon seed tissues on its survival. We compared the ability of A. citrulli to tolerate desiccation on filter paper discs and on host (watermelon) and nonhost (cabbage, corn and tomato) seeds to two seedborne (Xanthomonas campestris pv. campestris and Pantoea stewartii subsp. stewartii) and one soilborne (Ralstonia solanacearum) plant-pathogenic bacteria. A. citrulli survival on dry filter paper (>12 weeks) was similar to that of X. campestris pv. campestris but longer than P. stewartii subsp. stewartii. Ralstonia solanacearum survived longer than all other bacteria tested. On all seeds tested, A. citrulli and X. campestris pv. campestris populations declined by 5 orders of magnitude after 12 weeks of incubation at 4°C and 50% relative humidity, while R. solanacearum populations declined by 3 orders. P. stewartii subsp. stewartii was not recovered after 12 weeks of incubation. To determine the effect of tissue localization on bacterial survival, watermelon seeds infested with A. citrulli by flower stigma inoculation (resulting in bacterial localization in the embryo/endosperm) or by ovary pericarp inoculations (resulting in bacterial localization under the testa) were treated with peroxyacetic acid or chlorine (Cl2) gas. Following these treatments, a significantly higher reduction in BFB seed-to-seedling transmission was observed for seeds generated by ovary pericarp inoculation (≥89.5%) than for those generated by stigma inoculation (≤76.5%) (P<0.05). Additionally, higher populations of A. citrulli survived when the bacteria were localized to the embryo/endosperm versus the seed coat, suggesting that tissue localization is important for

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

    SciTech Connect

    Pisch, Julianna . E-mail: jpisch@bethisraelny.org; Belsley, Scott J.; Ashton, Robert; Wang Lin; Woode, Rudolph; Connery, Cliff

    2004-11-01

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

  11. 7 CFR 361.2 - Preemption of State and local laws; general restrictions on the importation of seed and screenings.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... restrictions on the importation of seed and screenings. 361.2 Section 361.2 Agriculture Regulations of the... IMPORTATION OF SEED AND SCREENINGS UNDER THE FEDERAL SEED ACT § 361.2 Preemption of State and local laws; general restrictions on the importation of seed and screenings. (a) The regulations in this part...

  12. 7 CFR 361.2 - Preemption of State and local laws; general restrictions on the importation of seed and screenings.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... restrictions on the importation of seed and screenings. 361.2 Section 361.2 Agriculture Regulations of the... IMPORTATION OF SEED AND SCREENINGS UNDER THE FEDERAL SEED ACT § 361.2 Preemption of State and local laws; general restrictions on the importation of seed and screenings. (a) The regulations in this part...

  13. 7 CFR 361.2 - Preemption of State and local laws; general restrictions on the importation of seed and screenings.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... restrictions on the importation of seed and screenings. 361.2 Section 361.2 Agriculture Regulations of the... IMPORTATION OF SEED AND SCREENINGS UNDER THE FEDERAL SEED ACT § 361.2 Preemption of State and local laws; general restrictions on the importation of seed and screenings. (a) The regulations in this part...

  14. 7 CFR 361.2 - Preemption of State and local laws; general restrictions on the importation of seed and screenings.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... restrictions on the importation of seed and screenings. 361.2 Section 361.2 Agriculture Regulations of the... IMPORTATION OF SEED AND SCREENINGS UNDER THE FEDERAL SEED ACT § 361.2 Preemption of State and local laws; general restrictions on the importation of seed and screenings. (a) The regulations in this part...

  15. 7 CFR 361.2 - Preemption of State and local laws; general restrictions on the importation of seed and screenings.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... restrictions on the importation of seed and screenings. 361.2 Section 361.2 Agriculture Regulations of the... IMPORTATION OF SEED AND SCREENINGS UNDER THE FEDERAL SEED ACT § 361.2 Preemption of State and local laws; general restrictions on the importation of seed and screenings. (a) The regulations in this part...

  16. Localization of Iron in Arabidopsis Seed Requires the Vacuolar Membrane Transporter VIT1

    SciTech Connect

    Kim,S.; Punshon, T.; Lanzirotti, A.; Li, L.; Alonso, J.; Ecker, J.; Kaplan, J.; Guerinot, M.

    2006-01-01

    Iron deficiency is a major human nutritional problem wherever plant-based diets are common. Using synchrotron x-ray fluorescence microtomography to directly visualize iron in Arabidopsis seeds, we show that iron is localized primarily to the provascular strands of the embryo. This localization is completely abolished when the vacuolar iron uptake transporter VIT1 is disrupted. Vacuolar iron storage is also critical for seedling development because vit1-1 seedlings grow poorly when iron is limiting. We have uncovered a fundamental aspect of seed biology that will ultimately aid the development of nutrient-rich seed, benefiting both human health and agricultural productivity.

  17. Measurement of /sup 125/I-low density lipoprotein uptake in selected tissues of the squirrel monkey by quantitative autoradiography

    SciTech Connect

    Tompkins, R.G.; Schnitzer, J.J.; Yarmush, M.L.; Colton, C.K.; Smith, K.A.

    1988-09-01

    A recently developed technique of absolute quantitative light microscopic autoradiography of /sup 125/I-labeled proteins in biologic specimens was used to measure /sup 125/I-low density lipoprotein (/sup 125/I-LDL) concentration levels in various tissues of the squirrel monkey after 30 minutes of in vivo LDL circulation. Liver and adrenal cortex exhibited high /sup 125/I-LDL concentrations, presumably because of binding to specific cell surface receptors and/or internalization in vascular beds with high permeability to LDL. High tissue concentrations of LDL were associated with the zona fasciculata and reticularis of the adrenal cortex and the interstitial cells of Leydig in the testis; significantly lower levels of /sup 125/I-LDL were observed in the adrenal medulla, the zona glomerulosa, and germinal centers of the testis. Contrary to previous reports, low /sup 125/I-LDL concentrations were observed throughout the gastrointestinal tract and in lymph nodes. In addition, multiple arterial intramural focal areas of high /sup 125/I-LDL concentrations were identified in arteries supplying the adrenal gland, lymph node, small bowel, and liver.

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

    NASA Astrophysics Data System (ADS)

    Antipas, V.; Dale, R. G.; Coles, I. P.

    2001-10-01

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

  19. Derivatives of cyclosporin compatible with antibody-based assays. I. The generation of (/sup 125/I)-labeled cyclosporin

    SciTech Connect

    Mahoney, W.C.; Orf, J.W.

    1985-03-01

    The immunosuppressive drug cyclosporin A, has been successfully iodinated to a specific activity of 300 Ci per gram. /sup 125/I-labeled cyclosporin and (/sup 3/H)cyclosporin are nearly equivalent as tracers in a radioimmunoassay in producing standard lines (suppression by unlabeled cyclosporin) and in assigning values to clinical samples. In addition, the (/sup 125/I)-labeled cyclosporin has greater than twice the sensitivity, and it is stable to long-term storage. Use of a (/sup 125/I)-labeled cyclosporin tracer is more convenient, more reproducible, more precise, and easier than the tritiated-cyclosporin alternative in radioimmunoassay of this compound.

  20. Heterogeneous distribution of 125I-insulin binding sites in the liver of fed and fasted mice.

    PubMed

    Nakanishi, M; Watanabe, M; Shimada, M

    1995-02-01

    A microradioautography made three min. after intravenous injection of 125I-insulin was used to study the distribution of insulin binding sites in the liver of fed and fasted mice. A substantial specific binding of 125I-insulin to liver parenchymal cells could be seen in these mice, whereas radioautographs from animals injected with 125I-insulin plus an excess of unlabelled insulin showed only trace amounts of silver grains. In both fed and fasted mice, a density gradient of the binding from the periportal zone to the perivenous zone was evident, and the binding in each zone was significantly higher in the fasted mice than in the fed mice.

  1. Determination of {sup 125}I and {sup 131}I in radioisotope wastes

    SciTech Connect

    Sang Hoon Kang; Ke Chon Choi; Lee, Heung N.; Sun Ho Han; Kwang Yong Jee

    2007-07-01

    In order to measure a low activity of {sup 125}I and {sup 131}I in radioisotope wastes, we took into consideration various sample preparation and separation methods, such as an acid decomposition, an acid leaching and a combustion method. In a previous study, the maximum chemical yield of iodine by an acid leaching was found to be 78.0 %. However, in this study, the maximum chemical yield of the acid decomposition method and the combustion method with a radioiodine reference solution was found to be 99.1 % and 84.5 %, respectively. We selected the acid decomposition method for the analysis of radioisotope waste samples due to its high chemical yield and short preparation and separation time. The chemical yield of the acid decomposition method depends on the reaction time at each experimental stage, added amount of H{sub 3}PO{sub 3} and H{sub 2}O{sub 2}, and the pH of the condensed solution and the condition of the AgI precipitation. The important point for the highest recovery rate from a acid decomposition method is to maintain enough reaction time and pour 10 ml of 30 % H{sub 3}PO{sub 3} before a distillation, and drop 1 ml of H{sub 2}O{sub 2} when the condensed solution is trapped in the Florence flask. Through a study of the acid decomposition method we found an optimal preparation and separation method of {sup 125}I and {sup 131}I in radioisotope wastes due to the merits of a short reaction time and high recovery rate, and a counting system was applied to LEPS for the {sup 125}I and HP Ge gamma-ray spectrometer for {sup 131}I. (authors)

  2. Rapid extraction, radioiodination, and in vivo catabolism of 125I-labeled fibrinogen in the horse

    SciTech Connect

    Coyne, C.P.; Hornof, W.J.; Kelly, A.B.; O'Brien, T.R.; DeNardo, S.J.

    1985-12-01

    Two methods were analyzed for the rapid extraction of equine fibrinogen from fresh plasma, using ammonium sulfate-sodium phosphate buffer. Fibrinogen from each of these 2 methods was then radiolabeled with 125I (half-life = 60.2 days, gamma = 35 keV), using monochloroiodine reagent. Mean protein-bound activity was 98.5% and mean clottable radioactivity was 94.1%. Radiolabeled fibrinogen administered IV to 15 horses had an overall mean (+/- SD) plasma half-life of 4.95 +/- 0.44 days.

  3. A defense in depth approach to radiation protection for 125I production activities.

    PubMed

    Culp, T; Potter, C A

    2001-08-01

    Not all operational radiation protection situations lend themselves to simple solutions. Often a Radiation Protection Program must be developed and implemented for difficult situations. A defense in depth approach to radiation protection was developed for 125I production activities. Defense in depth relies on key radiation protection elements that tend to be mutually supportive and in combination provide reasonable assurance that the overall desired level of protection has been provided. For difficult situations, defense in depth can provide both a reasonable and appropriate approach to radiation protection.

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

    NASA Astrophysics Data System (ADS)

    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.

  5. A local dormancy cline is related to the seed maturation environment, population genetic composition and climate

    PubMed Central

    Fernández-Pascual, Eduardo; Jiménez-Alfaro, Borja; Caujapé-Castells, Juli; Jaén-Molina, Ruth; Díaz, Tomás Emilio

    2013-01-01

    Background and Aims Seed dormancy varies within species in response to climate, both in the long term (through ecotypes or clines) and in the short term (through the influence of the seed maturation environment). Disentangling both processes is crucial to understand plant adaptation to environmental changes. In this study, the local patterns of seed dormancy were investigated in a narrow endemic species, Centaurium somedanum, in order to determine the influence of the seed maturation environment, population genetic composition and climate. Methods Laboratory germination experiments were performed to measure dormancy in (1) seeds collected from different wild populations along a local altitudinal gradient and (2) seeds of a subsequent generation produced in a common garden. The genetic composition of the original populations was characterized using intersimple sequence repeat (ISSR) PCR and principal co-ordinate analysis (PCoA), and its correlation with the dormancy patterns of both generations was analysed. The effect of the local climate on dormancy was also modelled. Key Results An altitudinal dormancy cline was found in the wild populations, which was maintained by the plants grown in the common garden. However, seeds from the common garden responded better to stratification, and their release from dormancy was more intense. The patterns of dormancy variation were correlated with genetic composition, whereas lower temperature and summer precipitation at the population sites predicted higher dormancy in the seeds of both generations. Conclusions The dormancy cline in C. somedanum is related to a local climatic gradient and also corresponds to genetic differentiation among populations. This cline is further affected by the weather conditions during seed maturation, which influence the receptiveness to dormancy-breaking factors. These results show that dormancy is influenced by both long-and short-term climatic variation. Such processes at such a reduced spatial

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

    SciTech Connect

    Johnson, M.P.; Mathis, C.A.; Shulgin, A.T.; Hoffman, A.J.; Nichols, D.E. )

    1990-01-01

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

  7. Effects of extracellular acetylcholine on muscarinic receptor binding assessed by [125I]dexetimide and a simple probe.

    PubMed

    Sánchez-Roa, P M; Wagner, H N; Villemagne, V L; London, E D; Lever, J R

    1998-10-01

    New pharmacologic approaches to enhance brain cholinergic function focus on increasing intrasynaptic acetylcholine. We examined the usefulness of a simple probe and [125I]dexetimide to evaluate in vivo the effects of extracellular acetylcholine on muscarinic receptor binding in the mouse brain. After radiotracer injection continuous time/activity curves were generated over 330 min. [125I]Dexetimide reached a plateau at 90 min post-injection. To increase extracellular acetylcholine, the anticholinesterase physostigmine was administered at 120 min, producing a reversible decrease in [125I]dexetimide specific binding (23%) for 30 min. These findings demonstrate that dynamic changes in extracellular acetylcholine can be evaluated by displacement of [125I]dexetimide binding in vivo using a simple probe system. PMID:9822886

  8. Quantitative studies with [125I]IgM anti-Lea

    PubMed Central

    Holburn, A. M.

    1973-01-01

    One of two volunteers with anti-Lea in their plasma developed rises in titre following the intramuscular injection of Lea glycoprotein. With partially purified [125I]IgM anti-Lea, it was found that the maximum number of antibody molecules that would bind to red cells of phenotype Le(a+b-) ranged from 4500 to 7300 molecules per cell for different donors. Lewis substance in serum samples was assayed by estimating its ability to inhibit the subsequent uptake of [125I]anti-Lea on to red cells. Somewhat unexpectedly, no clear correlation was found between the red cell and serum concentrations of Lea antigen of particular donors. The discrepancy between the amount of Lea on the red cells and in the serum may be due to the presence in the serum of antigen-bearing molecules (either glycoprotein or glycolipid) which fail to bind to red cells. IgM anti-Lea obtained from a single donor had an equilibrium constant of 8.4 × 109 l/mol. but no antibody activity was detectable in subunit preparations. It is concluded that IgM anti-Lea binds multivalently to each red cell. PMID:4717939

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

    SciTech Connect

    Rodd, D.; Caston, A.L.; Green M.H.; Farrell, P.A. )

    1990-02-26

    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 {sup 125}I BEP (1{mu}Ci/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 {sup 125}I 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.

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

    SciTech Connect

    Skofitsch, G.; Sills, M.A.; Jacobowitz, D.M.

    1986-11-01

    Galanin (GAL) binding sites in coronal sections of the rat brain were demonstrated using autoradiographic methods. Scatchard analysis of /sup 125/I-GAL binding to slide-mounted tissue sections revealed saturable binding to a single class of receptors with a Kd of approximately 0.2 nM. /sup 125/I-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.

  11. Plant regeneration from seeds responds to phylogenetic relatedness and local adaptation in Mediterranean Romulea (Iridaceae) species.

    PubMed

    Carta, Angelino; Hanson, Sarah; Müller, Jonas V

    2016-06-01

    Seed germination is the most important transitional event between early stages in the life cycle of spermatophytes and understanding it is crucial to understand plant adaptation and evolution. However, so far seed germination of phylogenetically closely related species has been poorly investigated. To test the hypothises that phylogenetically related plant species have similar seed ecophysiological traits thereby reflecting certain habitat conditions as a result of local adaptation, we studied seed dormancy and germination in seven Mediterranean species in the genus Romulea (Iridaceae). Both the across-species model and the model accounting for shared evolutionary history showed that cool temperatures (≤ 15°C) were the main factor that promoted seed germination. The absence of embryo growth before radicle emergence is consistent with a prompt germination response at cool temperatures. The range of temperature conditions for germination became wider after a period of warm stratification, denoting a weak primary dormancy. Altogether these results indicate that the studied species exhibit a Mediterranean germination syndrome, but with species-specific germination requirements clustered in a way that follows the phylogenetic relatedness among those species. In addition, species with heavier seeds from humid habitats showed a wider range of conditions for germination at dispersal time than species from dry habitats possessing lighter seeds. We conclude that while phylogenetically related species showed very similar germination requirements, there are subtle ecologically meaningful differences, confirming the onset of adaptation to local ecological factors mediated by species relatedness.

  12. Plant regeneration from seeds responds to phylogenetic relatedness and local adaptation in Mediterranean Romulea (Iridaceae) species.

    PubMed

    Carta, Angelino; Hanson, Sarah; Müller, Jonas V

    2016-06-01

    Seed germination is the most important transitional event between early stages in the life cycle of spermatophytes and understanding it is crucial to understand plant adaptation and evolution. However, so far seed germination of phylogenetically closely related species has been poorly investigated. To test the hypothises that phylogenetically related plant species have similar seed ecophysiological traits thereby reflecting certain habitat conditions as a result of local adaptation, we studied seed dormancy and germination in seven Mediterranean species in the genus Romulea (Iridaceae). Both the across-species model and the model accounting for shared evolutionary history showed that cool temperatures (≤ 15°C) were the main factor that promoted seed germination. The absence of embryo growth before radicle emergence is consistent with a prompt germination response at cool temperatures. The range of temperature conditions for germination became wider after a period of warm stratification, denoting a weak primary dormancy. Altogether these results indicate that the studied species exhibit a Mediterranean germination syndrome, but with species-specific germination requirements clustered in a way that follows the phylogenetic relatedness among those species. In addition, species with heavier seeds from humid habitats showed a wider range of conditions for germination at dispersal time than species from dry habitats possessing lighter seeds. We conclude that while phylogenetically related species showed very similar germination requirements, there are subtle ecologically meaningful differences, confirming the onset of adaptation to local ecological factors mediated by species relatedness. PMID:27516872

  13. Are Local Filters Blind to Provenance? Ant Seed Predation Suppresses Exotic Plants More than Natives

    PubMed Central

    Pearson, Dean E.; Icasatti, Nadia S.; Hierro, Jose L.; Bird, Benjamin J.

    2014-01-01

    The question of whether species’ origins influence invasion outcomes has been a point of substantial debate in invasion ecology. Theoretically, colonization outcomes can be predicted based on how species’ traits interact with community filters, a process presumably blind to species’ origins. Yet, exotic plant introductions commonly result in monospecific plant densities not commonly seen in native assemblages, suggesting that exotic species may respond to community filters differently than natives. Here, we tested whether exotic and native species differed in their responses to a local community filter by examining how ant seed predation affected recruitment of eighteen native and exotic plant species in central Argentina. Ant seed predation proved to be an important local filter that strongly suppressed plant recruitment, but ants suppressed exotic recruitment far more than natives (89% of exotic species vs. 22% of natives). Seed size predicted ant impacts on recruitment independent of origins, with ant preference for smaller seeds resulting in smaller seeded plant species being heavily suppressed. The disproportionate effects of provenance arose because exotics had generally smaller seeds than natives. Exotics also exhibited greater emergence and earlier peak emergence than natives in the absence of ants. However, when ants had access to seeds, these potential advantages of exotics were negated due to the filtering bias against exotics. The differences in traits we observed between exotics and natives suggest that higher-order introduction filters or regional processes preselected for certain exotic traits that then interacted with the local seed predation filter. Our results suggest that the interactions between local filters and species traits can predict invasion outcomes, but understanding the role of provenance will require quantifying filtering processes at multiple hierarchical scales and evaluating interactions between filters. PMID:25099535

  14. Β-amylase from starchless seeds of Trigonella foenum-graecum and its localization in germinating seeds.

    PubMed

    Srivastava, Garima; Kayastha, Arvind M

    2014-01-01

    Fenugreek (Trigonella foenum-graecum) seeds do not contain starch as carbohydrate reserve. Synthesis of starch is initiated after germination. A β-amylase from ungerminated fenugreek seeds was purified to apparent electrophoretic homogeneity. The enzyme was purified 210 fold with specific activity of 732.59 units/mg. Mr of the denatured enzyme as determined from SDS-PAGE was 58 kD while that of native enzyme calculated from size exclusion chromatography was 56 kD. Furthermore, its identity was confirmed to be β-amylase from MALDI-TOF analysis. The optimum pH and temperature was found to be 5.0 and 50°C, respectively. Starch was hydrolyzed at highest rate and enzyme showed a Km of 1.58 mg/mL with it. Antibodies against purified Fenugreek β-amylase were generated in rabbits. These antibodies were used for localization of enzyme in the cotyledon during different stages of germination using fluorescence and confocal microscopy. Fenugreek β-amylase was found to be the major starch degrading enzyme depending on the high amount of enzyme present as compared to α-amylase and also its localization at the periphery of amyloplasts. A new finding in terms of its association with protophloem was observed. Thus, this enzyme appears to be important for germination of seeds. PMID:24551136

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

    SciTech Connect

    Appel, N.M.; Mitchell, W.M.; Garlick, R.K.; Glennon, R.A.; Teitler, M.; De Souza, E.B. )

    1990-11-01

    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.

  16. The Comparative Effectiveness of Rodents and Dung Beetles as Local Seed Dispersers in Mediterranean Oak Forests

    PubMed Central

    Pérez-Ramos, Ignacio M.; Verdú, José R.; Numa, Catherine; Marañón, Teodoro; Lobo, Jorge M.

    2013-01-01

    The process of seed dispersal of many animal-dispersed plants is frequently mediated by a small set of biotic agents. However, the contribution that each of these dispersers makes to the overall recruitment may differ largely, with important ecological and management implications for the population viability and dynamics of the species implied in these interactions. In this paper, we compared the relative contribution of two local guilds of scatter-hoarding animals with contrasting metabolic requirements and foraging behaviours (rodents and dung beetles) to the overall recruitment of two Quercus species co-occurring in the forests of southern Spain. For this purpose, we considered not only the quantity of dispersed seeds but also the quality of the seed dispersal process. The suitability for recruitment of the microhabitats where the seeds were deposited was evaluated in a multi-stage demographic approach. The highest rates of seed handling and predation occurred in those microhabitats located under shrubs, mostly due to the foraging activity of rodents. However, the probability of a seed being successfully cached was higher in microhabitats located beneath a tree canopy as a result of the feeding behaviour of beetles. Rodents and beetles showed remarkable differences in their effectiveness as local acorn dispersers. Quantitatively, rodents were much more important than beetles because they dispersed the vast majority of acorns. However, they were qualitatively less effective because they consumed a high proportion of them (over 95%), and seeds were mostly dispersed under shrubs, a less suitable microhabitat for short-term recruitment of the two oak species. Our findings demonstrate that certain species of dung beetles (such as Thorectes lusitanicus), despite being quantitatively less important than rodents, can act as effective local seed dispersers of Mediterranean oak species. Changes in the abundance of beetle populations could thus have profound implications

  17. Brain damage from sup 125 I brachytherapy evaluated by MR imaging, a blood-brain barrier tracer, and light and electron microscopy in a rat model

    SciTech Connect

    Bernstein, M.; Marotta, T.; Stewart, P.; Glen, J.; Resch, L.; Henkelman, M. )

    1990-10-01

    Changes in normal rat brain were studied acutely, and at 3, 6, 9, and 12 months following interstitial brachytherapy with high-activity {sup 125}I seeds. An 80-Gy radiation dose was administered to an area with a 5.5-mm radius. Effects were measured with magnetic resonance (MR) imaging (with and without gadolinium enhancement), leakage of horseradish peroxidase (HRP), electron microscopy, and light microscopy. Significant histological damage was seen at radiation doses above 295 Gy, and breakdown of the blood-brain barrier was observed only in tissue receiving a dose of 165 Gy or greater. Blood-brain barrier breakdown increased up to the 6-month time point, and thereafter appeared to stabilize or decrease. The area of blood-brain barrier disruption indicated by gadolinium-enhanced MR imaging was greater than that indicated by leakage of HRP.

  18. HPLC-purified 2-(/sup 125/I)iodomelatonin labels multiple binding sites in hamster brain

    SciTech Connect

    Niles, L.P.; Pickering, D.S.; Sayer, B.G.

    1987-09-30

    Binding of 2-(/sup 125/I)iodomelatonin in hamster brain synaptosomal membranes at 0 degrees C is rapid, saturable, reversible and sensitive to heat and trypsin treatment. Computer resolution of curvilinear Scatchard plots yielded high- and low-affinity components as follows: Kd1 = 0.32 +/- 0.14 nM, Bmax1 = 5.6 +/- 1.7 fmol/mg protein and Kd2 = 10.5 +/- 3.2 nM, Bmax2 = 123 +/- 33 fmol/mg protein (n = 3). Competition experiments indicated that 2-iodomelatonin and prazosin are the most potent inhibitors of high-affinity binding. Unlike prazosin, several alpha-adrenergic agents and various neurotransmitters were ineffective. These findings suggest that prazosin may be a potent antagonist at a unique, non-alpha-adrenergic, high-affinity binding site for melatonin.

  19. /sup 125/I-labeled 8-phenylxanthine derivatives: antagonist radioligands for adenosine A1 receptors

    SciTech Connect

    Linden, J.; Patel, A.; Earl, C.Q.; Craig, R.H.; Daluge, S.M.

    1988-04-01

    A series of 8-phenylxanthine derivatives has been synthesized with oxyacetic acid on the para phenyl position to increase aqueous solubility and minimize nonspecific binding and iodinatable groups on the 1- or 3-position of the xanthine ring. The structure-activity relationship for binding of these compounds to A1 adenosine receptors of bovine and rat brain and A2 receptors of human platelets was examined. The addition of arylamine or photosensitive aryl azide groups to the 3-position of xanthine had little effect on A1 binding affinity with or without iodination, whereas substitutions at the 1-position caused greatly reduced A1 binding affinity. The addition of an aminobenzyl group to the 3-position of the xanthine had little effect on A2 binding affinity, but 3-aminophenethyl substitution decreased A2 binding affinity. Two acidic 3-(arylamino)-8-phenylxanthine derivatives were labeled with /sup 125/I and evaluated as A1 receptor radioligands. The new radioligands bound to A1 receptors with KD values of 1-1.25 nM. Specific binding represented over 80% of total binding. High concentrations of NaCl or other salts increased the binding affinity of acidic but not neutral antagonists, suggesting that interactions between ionized xanthines and receptors may be affected significantly by changes in ionic strength. On the basis of binding studies with these antagonists and isotope dilution with the agonist (/sup 125/I)N6-(4-amino-3-iodobenzyl)adenosine, multiple agonist affinity states of A1 receptors have been identified.

  20. In vivo seeding and cross-seeding of localized amyloidosis: a molecular link between type 2 diabetes and Alzheimer disease.

    PubMed

    Oskarsson, Marie E; Paulsson, Johan F; Schultz, Sebastian W; Ingelsson, Martin; Westermark, Per; Westermark, Gunilla T

    2015-03-01

    Several proteins have been identified as amyloid forming in humans, and independent of protein origin, the fibrils are morphologically similar. Therefore, there is a potential for structures with amyloid seeding ability to induce both homologous and heterologous fibril growth; thus, molecular interaction can constitute a link between different amyloid forms. Intravenous injection with preformed fibrils from islet amyloid polypeptide (IAPP), proIAPP, or amyloid-beta (Aβ) into human IAPP transgenic mice triggered IAPP amyloid formation in pancreas in 5 of 7 mice in each group, demonstrating that IAPP amyloid could be enhanced through homologous and heterologous seeding with higher efficiency for the former mechanism. Proximity ligation assay was used for colocalization studies of IAPP and Aβ in islet amyloid in type 2 diabetic patients and Aβ deposits in brains of patients with Alzheimer disease. Aβ reactivity was not detected in islet amyloid although islet β cells express AβPP and convertases necessary for Aβ production. By contrast, IAPP and proIAPP were detected in cerebral and vascular Aβ deposits, and presence of proximity ligation signal at both locations showed that the peptides were <40 nm apart. It is not clear whether IAPP present in brain originates from pancreas or is locally produced. Heterologous seeding between IAPP and Aβ shown here may represent a molecular link between type 2 diabetes and Alzheimer disease.

  1. Continuous Low-dose-rate Irradiation of Iodine-125 Seeds Inhibiting Perineural Invasion in Pancreatic Cancer

    PubMed Central

    Lu, Zheng; Dong, Teng-Hui; Si, Pei-Ren; Shen, Wei; Bi, Yi-Liang; Min, Min; Chen, Xin; Liu, Yan

    2016-01-01

    Background: Perineural invasion (PNI) is a histopathological characteristic of pancreatic cancer (PanCa). The aim of this study was to observe the treatment effect of continuous low-dose-rate (CLDR) irradiation to PNI and assess the PNI-related pain relief caused by iodine-125 (125I) seed implantation. Methods: The in vitro PNI model established by co-culture with dorsal root ganglion (DRG) and cancer cells was interfered under 2 and 4 Gy of 125I seeds CLDR irradiation. The orthotopic models of PNI were established, and 125I seeds were implanted in tumor. The PNI-related molecules were analyzed. In 30 patients with panCa, the pain relief was assessed using a visual analog scale (VAS). Pain intensity was measured before and 1 week, 2 weeks, and 1, 3, and 6 months after 125I seed implantation. Results: The co-culture of DRG and PanCa cells could promote the growth of PanCa cells and DRG neurites. In co-culture groups, the increased number of DRG neurites and pancreatic cells in radiation group was significantly less. In orthotopic models, the PNI-positive rate in radiation and control group was 3/11 and 7/11; meanwhile, the degrees of PNI between radiation and control groups was significant difference (P < 0.05). At week 2, the mean VAS pain score in patients decreased by 50% and significantly improved than the score at baseline (P < 0.05). The pain scores were lower in all patients, and the pain-relieving effect was retained about 3 months. Conclusions: The CLDR irradiation could inhibit PNI of PanCa with the value of further study. The CLDR irradiation could do great favor in preventing local recurrence and alleviating pain. PMID:27748339

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

    SciTech Connect

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

    1986-05-01

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

  3. Radiobiological effects of /sup 131/I and /sup 125/I on the DNA of the rat thyroid

    SciTech Connect

    Abdel-Nabi, H.; Ortman, J.A.

    1983-03-01

    One of the major disadvantages of the use of /sup 131/I in the treatment of thyrotoxicosis is the development of hypothyroidism. Alternatively, /sup 125/I has been proposed for thyrotoxicosis therapy, and was thought to be preferable to /sup 131/I because of the short range of its emitted soft electrons.Several studies have shown /sup 125/I to be as effective as /sup 131/I in the treatment of thyrotoxicosis, and equally likely to produce hupothyroidism. This work compared the radiobiological effects of /sup 131/I and /sup 125/I given in doses to deliver the same amount of radiation to the rat thyroid gland.These effects were studied by in vivo determination of single-strand DNA breaks by alkaline sucrose gradient sedimentation using the DABA fluorescent technique to detect the DNA. Serum T/sub 4/ and TSH concentrations and percentage T/sub 3/ uptake were determined by RIA. The incidence of hypothyroidism following /sup 131/I and /sup 125/I therapy was found to be the same (10% in each group). The extent of DNA damage following /sup 125/I therapy was greater than the damage induced by a larger dose of /sup 131/I.

  4. Effects of ageing on peroxidase activity and localization in radish (Raphanus sativus L.) seeds.

    PubMed

    Scialabba, A; Bellani, L M; Dell'Aquila, A

    2002-01-01

    Peroxidase activity was assayed in crude extracts of integument, cotyledons and embryo axis of radish seeds, deteriorated under accelerated ageing conditions. Over five days of ageing, in which germination decreased from 100 to 52%, the enzyme activity in integument was higher than that in other seed parts, increasing in the first days of ageing and then decreasing sharply in extremely aged seeds. Polyacrylamide gel electrophoresis analysis showed four peroxidase isoenzymes with MM of 98, 52.5, 32.8 and 29.5 kDa in the embryo axis of unaged seeds, and only the 32.8 and 29.5 kDa MM isoforms in the integument and cotyledons. In these parts of the seed, only the 29.5 kDa MM isoenzyme increased in activity in early days of ageing and decreased there-after. In the embryo axis, the 29.5 kDa MM isoenzyme activity increased slowly in the first day of ageing, while the 98 and 52.5 kDa MM isoenzyme activities disappeared. A cytochemical localization of peroxidase activity in the various tissues showed that main differences between unaged and extremely aged seeds occurred in the embryo axis.

  5. Assessment of conventional criteria for the early diagnosis of thrombophlebitis with the 125I-fibrinogen uptake test.

    PubMed

    DeNardo, G L; DeNardo, S J; Barnett, C A; Newcomer, K A; Jansholt, A L; Carretta, R F; Rose, A W

    1977-12-01

    Analysis of 55 positive tests of a total of 300 tests by conventional criteria revealed that 125I-fibrinogen provides useful information early enough for clinical management. Of the tests which were ultimately interpreted as positive by conventional criteria, at least one was positive at 3-4 hours in 67% of the tests and 98% of the tests were positive at 24 hours after the administration of 125I-fibrinogen. A 20% difference between contralateral identical locations of the legs and a 20% difference between adjacent locations of the ipsilateral leg were found with almost equal frequency in the positive tests, whereas a 20% increase at the same location was less sensitive. The 125I-fibrogen uptake test is a simple and accurate technique for early diagnosis of active thrombophlebitis.

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

    SciTech Connect

    Goulbourne, I.A.; Watson, H.; Davies, G.C.

    1987-12-01

    An experimental model of acute pancreatitis in rats has been used to study intrapulmonary /sup 125/I-fibrinogen and /sup 111/In-platelet deposition. Pancreatitis caused a significant increase in wet lung weight compared to normal, and this could be abolished by heparin or aspirin pretreatment. /sup 125/I-fibrinogen was deposited in the lungs of animals to a significantly greater degree than in controls (P less than 0.01). /sup 125/I-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.

  7. Concurrent versus sequential application of ferromagnetic hyperthermia and 125I brachytherapy of melanoma in an animal model.

    PubMed Central

    Mieler, W F

    1997-01-01

    OBJECTIVE: To determine the efficacy of concurrent versus sequential ferromagnetic hyperthermia (FMH), combined with Iodine-125 (125I) brachytherapy, in the treatment of uveal melanoma in a rabbit model. MATERIALS AND METHODS: A Greene melanoma cell line was implanted in rabbit eyes to establish a tumor model comparable to a uveal melanoma. Seventy-one tumor-containing rabbit eyes were treated with 125I brachytherapy at 20, 25, 35, 45, or 55 Gray (Gy)(38 eyes), and with either concurrent (15 eyes) or sequential (18 eyes) FMH, delivered at 48.2 degrees C for 1 hour. An additional 13 eyes were treated with FMH alone at 48.2 degrees C, either in a single heat application (5 eyes), or in a repetitive mode (8 eyes). The radiation and heat were delivered via an episcleral plaque. All tumors were followed with indirect ophthalmoscopy and echography. RESULTS: Tumors treated with 125I brachytherapy alone exhibited complete tumor regression in 50% of eyes at 42 Gy with none of the tumors responding to less than 35 Gy. FMH alone at 48.2 degrees C applied in one cycle limited tumor growth in 20% of eyes, while all eyes treated with repetitive heating exhibited complete tumor control. With concurrent application of FMH and 125I, the 50% tumor control rate occurred at 9.5 Gy, thus resulting in a thermal enhancement ratio (TER) of 4.4. With sequential treatment, the 50% tumor control rate was at 30 Gy, with a resultant TER of 1.4. No complications related to 125I brachytherapy were noted in any eyes, while transient retinal whitening was seen with the FMH. CONCLUSION: This study documents the enhanced synergistic interaction of concurrent FMH and 125I brachytherapy, compared to sequential treatment, in this rabbit melanoma model. PMID:9440189

  8. Similarities and differences between free 211At and 125I- transport in porcine thyroid epithelial cells cultured in bicameral chambers.

    PubMed

    Lindencrona, U; Nilsson, M; Forssell-Aronsson, E

    2001-01-01

    The transport and accumulation of free 211At and 125I- were investigated in thyrocytes cultured as monolayers in bicameral chambers under the influence of thyroid-stimulating hormone, stable iodide, ouabain and perchlorate. The results indicate that there are similarities and differences in the transport mechanisms of free 211At and 125I-. These results will be valuable in the development of radiation protection when handling and using 211At-labeled radiopharmaceuticals, and for the potential use of free 211At in radiation therapy of poorly differentiated thyroid cancer. PMID:11182563

  9. Calculation of excitation functions of proton, alpha and deuteron induced reactions for production of medical radioisotopes 122-125I

    NASA Astrophysics Data System (ADS)

    Artun, Ozan; Aytekin, Hüseyin

    2015-02-01

    In this work, the excitation functions for production of medical radioisotopes 122-125I with proton, alpha, and deuteron induced reactions were calculated by two different level density models. For the nuclear model calculations, the Talys 1.6 code were used, which is the latest version of Talys code series. Calculations of excitation functions for production of the 122-125I isotopes were carried out by using the generalized superfluid model (GSM) and Fermi-gas model (FGM). The results have shown that generalized superfluid model is more successful than Fermi-gas model in explaining the experimental results.

  10. Quantitative radioimmunohistochemical method using (/sup 125/I)-protein A to measure the content of methionine enkephalin in discrete rat brain areas

    SciTech Connect

    Correa, F.M.; Guilhaume, S.G.; Saavedra, J.M.

    1988-11-01

    We report a quantitative radioimmunohistochemical method, using (125I)-protein A in combination with a specific antibody to methionine enkephalin (Met-enk), for determination of the content of this peptide in discrete areas of rat brain. After paraformaldehyde fixation, rat brain sections were incubated with a Met-enk polyclonal antibody, followed by incubation with (125I)-protein A. After autoradiography with 3H-sensitive Ultrofilm, optical densities (OD) were quantified by computerized microdensitometry. The OD obtained were compared to a standard curve, constructed after determination by radioimmunoassay of the Met-enk content in corresponding brain areas from adjacent tissue sections. After comparing 15 different brain areas over a ninetyfold range of concentrations, we found a linear relationship between the content of Met-enk, as determined by radioimmunoassay, and the OD generated by autoradiography. The content of Met-enk in other discrete brain areas can be quantified by interpolation of the OD determined by autoradiography in the standard curve. The method allows, for the first time, precise quantification of peptide concentrations in discrete areas and nuclei from thin sections of rat brain. This technique has a more than 100-fold higher sensitivity than classical radioimmunoassays, with the additional advantage of neuroanatomical localization. It also has the potential for application to the quantification of many other antigens present in brain and other tissues.

  11. Direct method for detection and characterization of cell surface receptors for insulin by means of 125I-labeled autoantibodies against the insulin receptor.

    PubMed Central

    Jarrett, D B; Roth, J; Kahn, C R; Flier, J S

    1976-01-01

    Autoantibodies directed against the cell surface receptors for insulin are found in some patients with extreme insulin resistance. These antibodies specifically inhibit the binding of insulin to its receptor. A purified IgG fraction from one patient's plasma was labeled with 125I. The 125I-labeled antireceptor antibody, which initially represented about 0.3% of the total 125I-IgG, was enriched by selective adsorption and subsequent elution from cells rich in insulin receptors. The 125I-antireceptor antibody bound to cells and the binding was inhibited by whole plasma and purified IgG from this patient, as well as whole plasma from another patient with autoantibodies to the insulin receptor. Insulins that differed 300-fold in biological potency and affinity inhibited binding of 125I-antireceptor antibody in direct proportion to their ability to bind to the insulin receptor. The binding of 125I-antireceptor antibody was closely correlated with the binding of 125I-insulin over a wide range of receptor concentrations on different cell types. Experimentally induced reduction of the insulin receptor concentration was associated with parallel decreases in the binding of 125I-antireceptor antibody and 125I-insulin. The preparation of 125I-antireceptor antibody with a high specific activity by cytoadsorption and elution has provided a sensitive method for the detection of receptors and autoantibodies to cell surface components. PMID:1069300

  12. /sup 125/I-hippuran absorption from the human renal pelvis

    SciTech Connect

    Bratt, C.G.; Granerus, G.

    1986-09-01

    The absorption of /sup 125/I-hippuran from human renal pelvis was studied peroperatively in 18 patients with obstruction at the pelviureteric junction. Three types of experiment were included: absorption during induced diuresis, absorption at a constant intrapelvic pressure of 30 cm. H/sub 2/O, and excretion of the indicator by the contralateral kidney. Total and separate glomerular filtration rate were measured using /sup 51/Cr-EDTA clearance technique and isotope renography. Distal tubular function was evaluated as maximum concentration ability. During induced diuresis the intrapelvic pressure increased to an average maximum value of 31.6 cm. H/sub 2/O. The excretion of isotope from the contralateral kidney varied from one to 44% of the given dose. A significant correlation (r = 0.87) between the maximum intrapelvic pressure obtained and the amount of isotope excreted from the contralateral kidney was demonstrated. At a constant intrapelvic pressure of 30 cm. H/sub 2/O the excretion of isotope from the contralateral kidney varied from two to 26% of the dosage given. The low value probably depended on the impaired function of the obstructed kidney. Our results show the existence of a significant reflux from the renal pelvis of small molecules, which was affected by renal function, intrapelvic pressure and volume.

  13. Absorption of enzymatically active sup 125 I-labeled bovine milk xanthine oxidase fed to rabbits

    SciTech Connect

    Rzucidlo, S.J. ); Zikakis, J.P. )

    1990-05-01

    Rabbits fed a regular laboratory diet supplemented with a high-fat milk containing xanthine oxidase (XO) were studied to determine the presence of active XO in the blood. A pilot feeding study, where rabbits consumed a high-fat diet containing xanthine oxidase, showed a correlation between dairy food consumption and XO activity in the blood. Antibody to dietary XO was also found. In a second study, rabbits were fed ad libitum the high-fat milk and blood serum samples were tested weekly for XO activity. No elevation in serum XO activity was found. A third study showed that serum XO activity was increased when rabbits were force fed the high-fat milk. The final study consisted of force feeding {sup 125}I-labeled XO to one rabbit to ascertain whether the observed increase in serum XO was due to dietary or endogenous XO. Isoelectric focusing of sera collected from the test rabbit strongly suggested that at least a portion of the serum XO contained the radioactive label. This is the first direct evidence showing the uptake of dietary active XO from the gut.

  14. Altered (/sup 125/I)epidermal growth factor binding and receptor distribution in psoriasis

    SciTech Connect

    Nanney, L.B.; Stoscheck, C.M.; Magid, M.; King, L.E. Jr.

    1986-03-01

    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 (/sup 125/I)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.

  15. An ecological genetic delineation of local seed-source provenance for ecological restoration

    PubMed Central

    Krauss, Siegfried L; Sinclair, Elizabeth A; Bussell, John D; Hobbs, Richard J

    2013-01-01

    An increasingly important practical application of the analysis of spatial genetic structure within plant species is to help define the extent of local provenance seed collection zones that minimize negative impacts in ecological restoration programs. Here, we derive seed sourcing guidelines from a novel range-wide assessment of spatial genetic structure of 24 populations of Banksia menziesii (Proteaceae), a widely distributed Western Australian tree of significance in local ecological restoration programs. An analysis of molecular variance (AMOVA) of 100 amplified fragment length polymorphism (AFLP) markers revealed significant genetic differentiation among populations (ΦPT = 0.18). Pairwise population genetic dissimilarity was correlated with geographic distance, but not environmental distance derived from 15 climate variables, suggesting overall neutrality of these markers with regard to these climate variables. Nevertheless, Bayesian outlier analysis identified four markers potentially under selection, although these were not correlated with the climate variables. We calculated a global R-statistic using analysis of similarities (ANOSIM) to test the statistical significance of population differentiation and to infer a threshold seed collection zone distance of ∼60 km (all markers) and 100 km (outlier markers) when genetic distance was regressed against geographic distance. Population pairs separated by >60 km were, on average, twice as likely to be significantly genetically differentiated than population pairs separated by <60 km, suggesting that habitat-matched sites within a 30-km radius around a restoration site genetically defines a local provenance seed collection zone for B. menziesii. Our approach is a novel probability-based practical solution for the delineation of a local seed collection zone to minimize negative genetic impacts in ecological restoration. PMID:23919158

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

    PubMed

    John, C S; Bowen, W D; Fisher, S J; Lim, B B; Geyer, B C; Vilner, B J; Wahl, R 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[125I]-4-methoxybenzamide (P[125I]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[125I]MBA with Tc-99m sestamibi were made in a rat mammary tumor model. Sigma-1 affinity (Ki) for PIMBA in guinea pig brain membranes using [3H](+)pentazocine was found to be 11.82 +/- 0.68 nM, whereas sigma-2 affinity in rat liver using [3H]DTG (1,3-o-di-tolylguanidine) was 206 +/- 11 nM. Sites in guinea pig brain membranes labeled by P[125I]MBA showed high affinity for haloperidol, (+)-pentazocine, BD1008, and PIMBA (Ki = 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. Ki values for the inhibition of P[125I]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[125I]MBA in T47D cells as studied by Scatchard analysis showed saturable binding, with a Kd = 94 +/- 7 nM and a Bmax = 2035 +/- 305 fmol/mg of proteins. Biodistribution studies in Sprague-Dawley rats showed a rapid clearance of P[125I]MBA from the normal organs. The potential of PIMBA in imaging breast cancer was evaluated in Lewis rats bearing syngeneic RMT breast cancers, a cancer that

  17. Binding of an ( sup 125 I) labelled thromboxane A2/prostaglandin H2 receptor agonist to baboon platelets

    SciTech Connect

    Dorn, G.W. II; De Jesus, A. )

    1989-12-01

    To characterize the thromboxane A2/prostaglandin H2 (TXA2/PGH2) receptor on baboon platelets the binding of (125I)BOP was studied. (125I)BOP bound to washed baboon platelets in a saturable manner. Scatchard analysis of binding isotherms revealed a Kd of 1.12 +/- 0.08 nM and a binding capacity of 54 +/- 5 fmoles/10(8) platelets (326 sites/platelet). Several TXA2/PGH2 agonists and antagonists displaced (125I)BOP from its baboon platelet binding site with a rank order of potency similar to human platelets: I-BOP greater than SQ29548 greater than U46619 = I-PTA-OH greater than PTA-OH. I-BOP aggregated washed baboon platelets with an EC50 of 10 +/- 4 nM. The results indicate that (125I)BOP binds to the TXA2/PGH2 receptor on baboon platelets and that this receptor is similar to its human counterpart.

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

    SciTech Connect

    Kadan, M.J.

    1987-01-01

    /sup 125/I-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 /sup 125/I-lysergic acid diethylamide (/sup 125/I-LSD), the first radioiodinated ligand for serotonin receptor studies. The introduction of /sup 125/I at the 2 position of LSD increased both the affinity and selectivity of this compound for serotonin 5-HT/sub 2/ receptors in rat cortex. The high specific activity of /sup 125/I-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 /sup 125/I-LSD binds with high affinity to a class of serotonin receptors in the CNS of the marine mollusk Aplysia californica.

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

    PubMed

    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

  20. 2-(/sup 125/I)iodomelatonin binding sites in hamster brain membranes: pharmacological characteristics and regional distribution

    SciTech Connect

    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).

  1. Characterization of rat cerebral cortical beta adrenoceptor subtypes using (-)-( sup 125 I)-iodocyanopindolol

    SciTech Connect

    Tiong, A.H.; Richardson, J.S. )

    1990-01-01

    (-)-(125I)-Iodocyanopindolol (-(ICYP)), used to characterize beta adrenoceptors on membrane preparations from rat cerebral cortex, was shown to have affinity for both beta adrenoceptors and serotonin receptors. Therefore, 10 microM serotonin was added to the assays to prevent (-)ICYP binding to serotonin receptors. Under these conditions, (-)ICYP binding to the cortical membrane preparation was reversible and saturable, and the association reaction was very slow. The dissociation reaction was also very slow, and revealed two affinity states corresponding to a high and a low affinity state. Scatchard analysis showed a single class of binding sites with an equilibrium dissociation constant (KD) of 20.7 pM, and a maximal density of binding sites (Bmax) of 95.1 fmol/mg membrane protein. Displacement binding analyses revealed a potency series of (-) isoproterenol greater than (-) epinephrine equal to (-) norepinephrine, suggesting a predominance of the beta 1 adrenoceptor subtype. Detailed competition ligand binding studies with the selective beta 1 adrenoceptor antagonist ICI-89406 and the selective beta 2 adrenoceptor antagonist ICI-118551, showed that about 70% of the beta adrenoceptor population in the rat cortex is of the beta 1 subtype with the remainder being of the beta 2 subtype. We conclude that since (-)ICYP binds to both beta adrenoceptors and serotonin receptors, it is important to prevent the binding of (-)ICYP to serotonin receptors by adding a suppressing ligand like excess cold serotonin when assaying beta adrenoceptors. We have presented the first such characterization of rat cerebral cortical beta adrenoceptors with (-)ICYP in this study.

  2. Assessment of compensatory renal function and [125I]iothalamate clearance in sheep.

    PubMed

    Filippich, L J; English, P B; Ainscow, J

    1985-11-01

    Compensatory renal function and sodium [125I]iothalamate clearance were studied in 4 adult Merino ewes. Renal clearances of inulin (CIN), iothalamate (CIOT), and p-aminohippurate (CPAH) were used to measure renal function before and 7 and 170 days after 50% and 75% reductions in renal mass. Renal mass reduction to 50% of normal was achieved by ligation of the right renal artery, and to 25% of normal by ligating the right renal artery and branches of the left renal artery. Renal function (CIN and CPAH) after 50% renal mass reduction was 78% of normal on postligation day (PLD) 7 and 64% of normal on PLD 170. This decrease in renal function between PLD 7 and 170 was significant (P less than 0.05). Renal function (CIN and CPAH) after 75% renal mass reduction was 55% of normal on PLD 7 and 48% on PLD 170; however, this decrease in renal function between PLD 7 and 170 was not significant. Results indicated that, shortly after 50% renal mass reduction by renal arterial ligation, renal function in ewes was greater than that previously reported after unilateral nephrectomy and that a further decrease in renal function developed within 6 months after ligation. The mean CIOT in healthy ewes was 2.46 ml/min/kg of body weight. In healthy ewes and in ewes after renal mass reduction, regression of the simultaneous CIOT and CIN was CIOT = 0.276 + 1.05 CIN. The CIOT was higher than the corresponding CIN, and remained significantly (P less than 0.01) and consistently higher. Therefore, iothalamate can be used to estimate glomerular filtration rate in sheep, although a correction factor is required.

  3. Internalization and lysosomal association of (/sup 125/I)angiotensin II in norepinephrine-containing cells of the rat adrenal medulla

    SciTech Connect

    Bianchi, C.; Gutkowska, J.; Charbonneau, C.; Ballak, M.; Anand-Srivastava, M.B.; De Lean, A.; Genest, J.; Cantin, M.

    1986-10-01

    The morphological localization of (/sup 125/I)angiotensin II (AII) in the rat adrenal medulla (AM) was studied by light- and electron-microscopic radioautography in vivo. With light microscopy the presence of binding sites for AII in both norepinephrine-containing (NE) and epinephrine-containing (E) cells was confirmed. With electron microscopy, it was found that AII binds to the cell surface of NE cells, is progressively internalized, and is associated with lysosomes and Golgi complex within 20 min, whereas in E cells AII seems to be internalized earlier and recycled back to the cell surface within 5 min without any appreciable association with intracellular organelles. These results suggest different intracellular pathways for AII in NE and E cells of the rat AM.

  4. Metabolism of /sup 125/I-atrial natriuretic factor by vascular smooth muscle cells. Evidence for a peptidase that specifically removes the COOH-terminal tripeptide

    SciTech Connect

    Johnson, G.R.; Arik, L.; Foster, C.J.

    1989-07-15

    The addition of 200 pM monoiodinated human atrial natriuretic factor-(99-126) (125I-hANF) to cultured bovine aortic smooth muscle cells at 37/degree/C resulted in a rapid clearance from the medium (t1/2 approximately 7.5 min). Within 5 min, (125I)iodotyrosine126 (125I-Y), Arg125-(125I)iodotyrosine126 (125I-RY) and Phe124-Arg-(125)iodotyrosine126 (125I-FRY) appeared in the medium. The identities of these degradation products were confirmed by (1) retention time on high performance liquid chromatography (HPLC) relative to standards, (2) products generated by digestion with aminopeptidase M, and (3) the absence of the Met110. Preincubation of the cells with ammonium chloride or chloroquine resulted in a significant increase in the intracellular accumulation of radiolabel, indicative of endocytosis and rapid delivery of 125I-hANF to an acidic intracellular compartment (endosome and/or lysosome). Neither ammonium chloride, chloroquine, nor excess unlabeled hANF blocked the rapid appearance in the medium of 125I-RY or 125I-FRY. Bestatin inhibited the generation of 125I-RY, with a concomitant increase in 125I-FRY, suggesting that the 125I-RY is produced by aminopeptidase action on 125I-FRY. The endopeptidase 24.11 (enkephalinase) inhibitor, SCH 39370, did not inhibit the formation of 125I-FRY. These results provide evidence of a peptidase capable of specifically removing the COOH-terminal tripeptide from 125I-hANF. The COOH-terminal tripeptide, Phe124-Arg-Tyr126, was also isolated from cell digests of hANF by HPLC and its identity confirmed by amino acid analysis. Since it is generally believed that the COOH-terminal tripeptide is critical to many of atrial natriuretic factor-(99-126)'s bioactivities, this enzyme may be involved in the inactivation of atrial natriuretic factor-(99-126) in target tissues.

  5. N1-methyl-2-125I-lysergic acid diethylamide, a preferred ligand for in vitro and in vivo characterization of serotonin receptors.

    PubMed

    Hoffman, B J; Scheffel, U; Lever, J R; Karpa, M D; Hartig, P R

    1987-01-01

    Methylation of 2-125I-lysergic acid diethylamide (125I-LSD) at the N1 position produces a new derivative, N1-methyl-2-125I-lysergic acid diethylamide (125I-MIL), with improved selectivity and higher affinity for serotonin 5-HT2 receptors. In rat frontal cortex homogenates, specific binding of 125I-MIL represents 80-90% of total binding, and the apparent dissociation constant (KD) for serotonin 5-HT2 receptors is 0.14 nM (using 2 mg of tissue/ml). 125I-MIL also displays a high affinity for serotonin 5-HT1C receptors, with an apparent dissociation constant of 0.41 nM at this site. 125I-MIL exhibits at least 60-fold higher affinity for serotonin 5-HT2 receptors than for other classes of neurotransmitter receptors, with the dopamine D2 receptor as its most potent secondary binding site. Studies of the association and dissociation kinetics of 125I-MIL reveal a strong temperature dependence, with very slow association and dissociation rates at 0 degree C. Autoradiographic experiments confirm the improved specificity of 125I-MIL. Selective labeling of serotonin receptors was observed in all brain areas examined. In vivo binding studies in mice indicate that 125I-MIL is the best serotonin receptor label yet described, with the highest frontal cortex to cerebellum ratio of any serotonergic radioligand. 125I-MIL is a promising ligand for both in vitro and in vivo labeling of serotonin receptors in the mammalian brain.

  6. Seeding method influences warm-season grass abundance and distribution but not local diversity in grassland restoration

    USGS Publications Warehouse

    Yurkonis, Kathryn A.; Wilsey, Brian J.; Moloney, Kirk A.; Drobney, Pauline; Larson, Diane L.

    2010-01-01

    Ecological theory predicts that the arrangement of seedlings in newly restored communities may influence future species diversity and composition. We test the prediction that smaller distances between neighboring seeds in drill seeded grassland plantings would result in lower species diversity, greater weed abundance, and larger conspecific patch sizes than otherwise similar broadcast seeded plantings. A diverse grassland seed mix was either drill seeded, which places seeds in equally spaced rows, or broadcast seeded, which spreads seeds across the ground surface, into 24 plots in each of three sites in 2005. In summer 2007, we measured species abundance in a 1 m2 quadrat in each plot and mapped common species within the quadrat by recording the most abundant species in each of 64 cells. Quadrat-scale diversity and weed abundance were similar between drilled and broadcast plots, suggesting that processes that limited establishment and controlled invasion were not affected by such fine-scale seed distribution. However, native warm-season (C4) grasses were more abundant and occurred in less compact patches in drilled plots. This difference in C4 grass abundance and distribution may result from increased germination or vegetative propagation of C4 grasses in drilled plots. Our findings suggest that local plant density may control fine-scale heterogeneity and species composition in restored grasslands, processes that need to be further investigated to determine whether seed distributions can be manipulated to increase diversity in restored grasslands.

  7. Seeding Method Influences Warm-Season Grass Abundance and Distribution but not Local Diversity in Grassland Restoration

    USGS Publications Warehouse

    Yurkonis, K.A.; Wilsey, B.J.; Moloney, K.A.; Drobney, P.; Larson, D.L.

    2010-01-01

    Ecological theory predicts that the arrangement of seedlings in newly restored communities may influence future species diversity and composition. We test the prediction that smaller distances between neighboring seeds in drill seeded grassland plantings would result in lower species diversity, greater weed abundance, and larger conspecific patch sizes than otherwise similar broadcast seeded plantings. A diverse grassland seed mix was either drill seeded, which places seeds in equally spaced rows, or broadcast seeded, which spreads seeds across the ground surface, into 24 plots in each of three sites in 2005. In summer 2007, we measured species abundance in a 1 m2 quadrat in each plot and mapped common species within the quadrat by recording the most abundant species in each of 64 cells. Quadrat-scale diversity and weed abundance were similar between drilled and broadcast plots, suggesting that processes that limited establishment and controlled invasion were not affected by such fine-scale seed distribution. However, native warm-season (C4) grasses were more abundant and occurred in less compact patches in drilled plots. This difference in C4 grass abundance and distribution may result from increased germination or vegetative propagation of C4 grasses in drilled plots. Our findings suggest that local plant density may control fine-scale heterogeneity and species composition in restored grasslands, processes that need to be further investigated to determine whether seed distributions can be manipulated to increase diversity in restored grasslands. ?? 2010 Society for Ecological Restoration International.

  8. Synthesis and biological evaluation of [125I]- and [123I]-4-iododexetimide, a potent muscarinic cholinergic receptor antagonist.

    PubMed

    Wilson, A A; Dannals, R F; Ravert, H T; Frost, J J; Wagner, H N

    1989-05-01

    A series of halogenated racemic analogues of dexetimide (1) was synthesized and their affinity for the muscarinic cholinergic receptor measured. One analogue, 4-iododexetimide (21), was efficiently labeled with 125I and 123I at high specific activity. In vitro binding studies and in vivo biodistribution studies suggest that 123I-labeled 21 may be useful for imaging muscarinic cholinergic receptors in the living human brain with single photon emission computed tomography. PMID:2785211

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

    SciTech Connect

    Langone, J.J.

    1980-05-15

    A sensitive and specific solid-phase radioimmunoassay for 5-methyltetrahydrofolate (5-MTHFA) has been developed. /sup 125/I-Labeled staphylococcal Protein A (/sup 125/I-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 /sup 125/I-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.

  10. Behaviour of 125I-fibrinogen and 131I-albumin in experimental galactosamine-induced hepatitis.

    PubMed Central

    Mahn, I; Merkel, H; Sattler, E L; Müller-Berghaus, G

    1977-01-01

    The turnover of 125I-labelled fibrinogen and 131I-labelled albumin was studied in the course of galactosamine-induced hepatitis in rabbits. In addition to galactosamine, some animals were treated with epsilon-aminocaproic acid (EACA) to inhibit the activation of the fibrinolytic system. The infusion of galactosamine and EACA caused generation of fibrin-rich microclots in the renal glomerular capillaries in seven out of 12 rabbits. Correspondingly, the incorporation of 125I-radioactivity into liver, spleen, and kidneys was pronounced in galactosamine- and EACA-treated rabbits compared with control animals treated with EACA. An acceleration of the 125I-fibrinogen elimination from the plasma was observed between eight and 12 hours after the start of the galactosamine infusion. The administration of heparin in addition to galactosamine and EACA prevented the occurrence of intravascular coagulation, but shortened the survival times of the animals because of bleeding into visceral organs. The elimination of 131I-albumin in plasma as well as the distribution of 131I-radioactivity in organs were similar in all the rabbits independent of the treatment with galactosamine, EACA, or heparin. The experiments indicate that, in addition to diminished synthesis of coagulation factors, disseminated intravascular coagulation is involved in galactosamine-induced hepatitis and contributes to the haemostatic disorder. PMID:873336

  11. Reoxygenation, but neither hypoxia nor intermittent ischemia, increases ( sup 125 I)endothelin-1 binding to rat cardiac membranes

    SciTech Connect

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

    1990-03-01

    Standard binding techniques were used to establish whether either hypoxia, reoxygenation, perfusion under acidotic conditions, or stunning of the myocardium resembles ischemia and postischemic reperfusion in increasing cardiac membrane ({sup 125}I)endothelin-1 (ET-1) binding site density (Bmax). Membranes from aerobically perfused rat hearts bound ({sup 125}I)ET-1 to a single population of sites, with an affinity (KD) of 0.093 +/- 0.004 nM and a Bmax of 98.8 +/- 5.2 fmol/mg of protein. Bmax was increased (p less than 0.01) after 30 min of global ischemia, and further increased upon reperfusion, without changes in KD or selectivity. Neither three 10 min episodes of ischemia separated by 15 min of perfusion, nor perfusion at pH 6.8 instead of 7.4, nor 60 min of hypoxia altered Bmax, KD, or selectivity. Reoxygenation after 60 min of hypoxia increased Bmax (p less than 0.01) and KD (p less than 0.01) without changing selectivity. These results are interpreted to mean that the ischemia-induced increase in Bmax for ({sup 125}I)ET-1 cannot be explained simply in terms of the ischemia-induced acidosis, or the accompanying reduction in tissue adenosine triphosphate and creatine phosphate.

  12. Protein radioiodination in a radioassay laboratory: evaluation of commercial Na/sup 125/I reagents and related biohazards

    SciTech Connect

    Hamilton, R.G.; Button, T.M.

    1980-01-01

    Three commercial Na/sup 125/I 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 Na/sup 125/I 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 Na/sup 125/I 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.

  13. Dosimetric comparison of 106Ru and 125I plaques for treatment of shallow (

    PubMed

    Wilkinson, D A; Kolar, M; Fleming, P A; Singh, A D

    2008-10-01

    The aim of this study was to compare dosimetric parameters between iodine-125 ((125)I) and ruthenium-106 ((106)Ru) plaques of similar sizes in the treatment of choroidal melanomas. The study design included retrospective double planning of each case. 26 consecutive patients with choroidal melanomas measuring 5 mm or less in thickness were included. Dose distributions were calculated using Plaque Simulator treatment-planning software for a prescription of 85 Gy to the tumour apex. Doses to the outer sclera, lens, fovea and optic disc were obtained for each case using appropriately sized plaques of each isotope. Statistical inferences were made using the non-parametric Wilcoxon signed rank test. The mean dose to the macula, disc and lens was 18%, 53% and 89% less, respectively, with (106)Ru than with (125)I. Scleral doses were greater for (106)Ru. The use of collaborative ocular melanoma study dosimetry results in even higher mean doses to the macula, disc, lens and sclera. Two-dimensional dose distributions and dose volume histograms demonstrated the increase in dose outside the tumour volume using (125)I. This comparison shows that, for tumours not exceeding 5 mm in thickness, the use of (106)Ru plaques has the potential to reduce the radiation dose to nearby normal structures and possibly lower the risk of radiation-induced visual loss.

  14. Dual-head gamma camera system for intraoperative localization of radioactive seeds

    NASA Astrophysics Data System (ADS)

    Arsenali, B.; de Jong, H. W. A. M.; Viergever, M. A.; Dickerscheid, D. B. M.; Beijst, C.; Gilhuijs, K. G. A.

    2015-10-01

    Breast-conserving surgery is a standard option for the treatment of patients with early-stage breast cancer. This form of surgery may result in incomplete excision of the tumor. Iodine-125 labeled titanium seeds are currently used in clinical practice to reduce the number of incomplete excisions. It seems likely that the number of incomplete excisions can be reduced even further if intraoperative information about the location of the radioactive seed is combined with preoperative information about the extent of the tumor. This can be combined if the location of the radioactive seed is established in a world coordinate system that can be linked to the (preoperative) image coordinate system. With this in mind, we propose a radioactive seed localization system which is composed of two static ceiling-suspended gamma camera heads and two parallel-hole collimators. Physical experiments and computer simulations which mimic realistic clinical situations were performed to estimate the localization accuracy (defined as trueness and precision) of the proposed system with respect to collimator-source distance (ranging between 50 cm and 100 cm) and imaging time (ranging between 1 s and 10 s). The goal of the study was to determine whether or not a trueness of 5 mm can be achieved if a collimator-source distance of 50 cm and imaging time of 5 s are used (these specifications were defined by a group of dedicated breast cancer surgeons). The results from the experiments indicate that the location of the radioactive seed can be established with an accuracy of 1.6 mm  ±  0.6 mm if a collimator-source distance of 50 cm and imaging time of 5 s are used (these experiments were performed with a 4.5 cm thick block phantom). Furthermore, the results from the simulations indicate that a trueness of 3.2 mm or less can be achieved if a collimator-source distance of 50 cm and imaging time of 5 s are used (this trueness was achieved for all 14 breast phantoms which

  15. The interaction of /sup 125/I-insulin with cultured 3T3-L1 adipocytes: quantitative analysis by the hypothetical grain method

    SciTech Connect

    Fan, J.Y.; Carpentier, J.L.; Van Obberghen, E.; Blackett, N.M.; Grunfeld, C.; Gorden, P.; Orci, L.

    1983-07-01

    The murine 3T3-L1 fibroblast under appropriate incubation conditions differentiates into an adipocyte phenotype. This 3T3-L1 adipocyte exhibits many of the morphologic, biochemical, and insulin-responsive features of the normal rodent adipocyte. Using quantitative electron microscopic (EM) autoradiography we find that, when /sup 125/I-insulin is incubated with 3T3-L1 adipocytes, the ligand at early times of incubation localizes to the plasma membrane of the cell preferentially to microvilli and coated pits. When the incubation is continued at 37 degrees C, /sup 125/I-insulin is internalized by the cells and preferential binding to the villous surface is lost. With the internalization of the ligand, two intracellular structures become labeled, as determined by the method of hypothetical grain analysis. These include large clear, presumably endocytotic, vesicles and multivesicular bodies. Over the first hour of incubation the labeling of these structures increases in parallel, but in the second hour they diverge: the labeling of multivesicular bodies and other lysosomal forms continuing to increase and the labeling of large clear vesicles decreasing. At 3 hours limited but significant labeling occurs in small Golgi-related vesicles that have the typical distribution of GERL. The distinct morphologic features of this cell make it ideal for a quantitative morphologic analysis and allow for an unambiguous view of the sequence of events involved in receptor-mediated endocytosis of a polypeptide hormone. These events are likely to be representative of the processing of insulin by the mature rodent adipocyte.

  16. Subcellular localization and vacuolar targeting of sorbitol dehydrogenase in apple seed.

    PubMed

    Wang, Xiu-Ling; Hu, Zi-Ying; You, Chun-Xiang; Kong, Xiu-Zhen; Shi, Xiao-Pu

    2013-09-01

    Sorbitol is the primary photosynthate and translocated carbohydrate in fruit trees of the Rosaceae family. NAD(+)-dependent sorbitol dehydrogenase (NAD-SDH, EC 1.1.1.14), which mainly catalyzes the oxidation of sorbitol to fructose, plays a key role in regulating sink strength in apple. In this study, we found that apple NAD-SDH was ubiquitously distributed in epidermis, parenchyma, and vascular bundle in developing cotyledon. NAD-SDH was localized in the cytosol, the membranes of endoplasmic reticulum and vesicles, and the vacuolar lumen in the cotyledon at the middle stage of seed development. In contrast, NAD-SDH was mainly distributed in the protein storage vacuoles in cotyledon at the late stage of seed development. Sequence analysis revealed there is a putative signal peptide (SP), also being predicated to be a transmembrane domain, in the middle of proteins of apple NAD-SDH isoforms. To investigate whether the putative internal SP functions in the vacuolar targeting of NAD-SDH, we analyzed the localization of the SP-deletion mutants of MdSDH5 and MdSDH6 (two NAD-SDH isoforms in apple) by the transient expression system in Arabidopsis protoplasts. MdSDH5 and MdSDH6 were not localized in the vacuoles after their SPs were deleted, suggesting the internal SP functions in the vacuolar targeting of apple NAD-SDH.

  17. What's the meaning of local? Using molecular markers to define seed transfer zones for ecological restoration in Norway.

    PubMed

    Jørgensen, Marte Holten; Elameen, Abdelhameed; Hofman, Nadine; Klemsdal, Sonja; Malaval, Sandra; Fjellheim, Siri

    2016-06-01

    According to the Norwegian Diversity Act, practitioners of restoration in Norway are instructed to use seed mixtures of local provenance. However, there are no guidelines for how local seed should be selected. In this study, we use genetic variation in a set of alpine species (Agrostis mertensii, Avenella flexuosa, Carex bigelowii, Festuca ovina, Poa alpina and Scorzoneroides autumnalis) to define seed transfer zones to reduce confusion about the definition of 'local seeds'. The species selected for the study are common in all parts of Norway and suitable for commercial seed production. The sampling covered the entire alpine region (7-20 populations per species, 3-15 individuals per population). We characterised genetic diversity using amplified fragment length polymorphisms. We identified different spatial genetic diversity structures in the species, most likely related to differences in reproductive strategies, phylogeographic factors and geographic distribution. Based on results from all species, we suggest four general seed transfer zones for alpine Norway. This is likely more conservative than needed for all species, given that no species show more than two genetic groups. Even so, the approach is practical as four seed mixtures will serve the need for restoration of vegetation in alpine regions in Norway. PMID:27247618

  18. What's the meaning of local? Using molecular markers to define seed transfer zones for ecological restoration in Norway.

    PubMed

    Jørgensen, Marte Holten; Elameen, Abdelhameed; Hofman, Nadine; Klemsdal, Sonja; Malaval, Sandra; Fjellheim, Siri

    2016-06-01

    According to the Norwegian Diversity Act, practitioners of restoration in Norway are instructed to use seed mixtures of local provenance. However, there are no guidelines for how local seed should be selected. In this study, we use genetic variation in a set of alpine species (Agrostis mertensii, Avenella flexuosa, Carex bigelowii, Festuca ovina, Poa alpina and Scorzoneroides autumnalis) to define seed transfer zones to reduce confusion about the definition of 'local seeds'. The species selected for the study are common in all parts of Norway and suitable for commercial seed production. The sampling covered the entire alpine region (7-20 populations per species, 3-15 individuals per population). We characterised genetic diversity using amplified fragment length polymorphisms. We identified different spatial genetic diversity structures in the species, most likely related to differences in reproductive strategies, phylogeographic factors and geographic distribution. Based on results from all species, we suggest four general seed transfer zones for alpine Norway. This is likely more conservative than needed for all species, given that no species show more than two genetic groups. Even so, the approach is practical as four seed mixtures will serve the need for restoration of vegetation in alpine regions in Norway.

  19. In vitro and in vivo characterization of 4-[125I]iododexetimide binding to muscarinic cholinergic receptors in the rat heart.

    PubMed

    Matsumura, K; Uno, Y; Scheffel, U; Wilson, A A; Dannals, R F; Wagner, H N

    1991-01-01

    4-[125I]iododexetimide binding to muscarinic cholinergic receptors (mAChR) was evaluated in the rat heart. 4-[125I]iododexetimide displayed high in vitro affinity (Kd = 14.0 nM) for rat myocardial mAChR. In vivo, there was high accumulation of 4-[125I]iododexetimide in the rat atrium and ventricle which could be blocked by approximately 60% by preinjection of atropine. In contrast, accumulation of the radiolabeled stereoisomer, 4-[125I]iodolevetimide, was 63% lower than 4-[125I]iodolevetimide and was not blocked by atropine. The blood clearance of 4-[125I]iododexetimide was rapid, providing heart-to-blood ratios of up to 14:1; however, heart-to-lung and heart-to-liver ratios were below unity. The data indicate that 4-[125I]iododexetimide binds potently to rat mAChR. However, since nonspecific binding is relatively high, it is not clear whether iododexetimide labeled with 123I will be useful in SPECT imaging studies of myocardial mAChR. Further studies in humans are indicated. PMID:1988640

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

    PubMed

    Herod, Matthew N; Cornett, R Jack; Clark, Ian D; Kieser, W E; Jean, Gilles St

    2014-12-01

    Iodine-129 ((129)I) is a biophilic, naturally occurring radioisotope (half-life: 1.57 × 10(7) 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 (125)I tracer was used as well as humic acid labeled with (125)I to simulate the behavior of (129)I and (127)I in complex organic substances and extract iodine regardless of how it is partitioned. Using these tracers we explored the effect on recovery of (125)I under a variety of combustion parameters. These include carrier gas flow rate and iodine volatilization temperature. We observed that the best recoveries of (125)I were at flow rates between 400 and 800 mL/min and most (125)I 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 (129)I concentration of the seaweed ranged between 4

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

    PubMed

    Herod, Matthew N; Cornett, R Jack; Clark, Ian D; Kieser, W E; Jean, Gilles St

    2014-12-01

    Iodine-129 ((129)I) is a biophilic, naturally occurring radioisotope (half-life: 1.57 × 10(7) 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 (125)I tracer was used as well as humic acid labeled with (125)I to simulate the behavior of (129)I and (127)I in complex organic substances and extract iodine regardless of how it is partitioned. Using these tracers we explored the effect on recovery of (125)I under a variety of combustion parameters. These include carrier gas flow rate and iodine volatilization temperature. We observed that the best recoveries of (125)I were at flow rates between 400 and 800 mL/min and most (125)I 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 (129)I concentration of the seaweed ranged between 4

  2. Pharmacological characterization of [(125)I]CHIBA-1006 binding, a new radioligand for α7 nicotinic acetylcholine receptors, to rat brain membranes.

    PubMed

    Wu, Jin; Toyohara, Jun; Tanibuchi, Yuko; Fujita, Yuko; Zhang, Jichun; Chen, Hongxian; Matsuo, Masaaki; Wang, Rong Fu; Hashimoto, Kenji

    2010-11-11

    The α7 nicotinic acetylcholine receptors (nAChRs) play an important role in the pathophysiology of neuropsychiatric diseases such as schizophrenia and Alzheimer's disease. However, there are currently no suitable small molecule radioligands for imaging α7 nAChRs in the brain. In this study, we synthesized the novel radioligand [(125)I]4-iodophenyl 1,4-diazaicyclo[3.2.2]nonane-4-carboxylate ([(125)I]CHIBA-1006), a iodine-derivative of the selective α7 nAChR agonist SSR180711, and studied the characterization of [(125)I]CHIBA-1006 binding to rat brain membranes. The assays of [(125)I]CHIBA-1006 binding to rat brain membranes were performed at 4°C. The presence of a single saturable high-affinity binding component for [(125)I]CHIBA-1006 in the rat brain was shown. Scatchard analysis revealed an apparent equilibrium dissociation constant (K(d)) of 88.2±21.4nM and a maximal number of binding sites (B(max)) of 65.4±6.8fmol/mg protein (mean±SEM, n=4). The specific binding of [(125)I]CHIBA-1006 was inhibited by a number of α7 nAChR-selective ligands (e.g., unlabeled CHIBA-1006, SSR180711, CHIBA-1001, MG624 and A844606), suggesting a similarity among α7 nAChR pharmacological profiles. In contrast, α-bungarotoxin, MLA, and nicotine showed very weak affinity for [(125)I]CHIBA-1006 binding. The regional distribution of [(125)I]CHIBA-1006 binding to crude membranes from dissected regions of the rat brain was different from that of [(125)I]α-bungarotoxin binding, suggesting that [(125)I]CHIBA-1006 binding sites may not be identical to [(125)I]α-bungarotoxin binding sites in the rat brain. The present findings suggest that [(125)I]CHIBA-1006 would be a useful new small molecule radioligand for α7 nAChRs in the brain. PMID:20816767

  3. Comparison of margin status and lesional size between radioactive seed localized vs conventional wire localized breast lumpectomy specimens.

    PubMed

    Rarick, Jason; Kimler, Bruce F; Tawfik, Ossama

    2016-04-01

    Despite the known benefits of the use of radioactive seed localization (RSL), few studies have looked at the resultant pathologic marginal status of these lumpectomy specimens, especially in regard to different definitions of close/positive margins. We compared the marginal status of lumpectomy specimens removed by either RSL or conventional wire localization (CWL) techniques. A total of 106 lumpectomy specimens including 62 by CWL and 44 by RSL for invasive ductal and lobular carcinomas were compared. Data on gross and microscopic surgical margin status, tumor type and grade, and demographic information were retrospectively collected. There was no difference between the techniques in terms of tumor characteristics including size, histologic grade, lymph node positivity, or age. Although the distributions are very similar between CWL and RSL specimens for final marginal assessments (P=.69), there is a (modest) statistically significant difference in the distribution for margin classifications based on gross assessments (P=.040), specifically more RSL specimens exhibiting tumor within 1mm of the closest margin. Concordance between gross and microscopic lesion measurements is highest for invasive ductal carcinoma grade 3 for both CWL and RSL lumpectomies (78.6% and 80.0%). This study shows that there were no significant marginal status differences between RSL and CWL lumpectomy specimens with invasive carcinoma. Rather, what was relevant is whether the entire specimen could be classified as having negative/close margins. Significant workflow challenges in surgical pathology laboratories are expected with the adoption of the RSL process.

  4. Genetic delineation of local provenance defines seed collection zones along a climate gradient.

    PubMed

    Hufford, Kristina M; Veneklaas, Erik J; Lambers, Hans; Krauss, Siegfried L

    2016-01-01

    Efforts to re-establish native plant species should consider intraspecific variation if we are to restore genetic diversity and evolutionary potential. Data describing spatial genetic structure and the scale of adaptive differentiation are needed for restoration seed sourcing. Genetically defined provenance zones provide species-specific guidelines for the distance within which seed transfer likely maintains levels of genetic diversity and conserves locally adapted traits. While a growing number of studies incorporate genetic marker data in delineation of local provenance, they often fail to distinguish the impacts of neutral and non-neutral variation. We analysed population genetic structure for 134 amplified fragment length polymorphism (AFLP) markers in Stylidium hispidum (Stylidiaceae) along a north-south transect of the species' range with the goal to estimate the distance at which significant genetic differences occur among source and recipient populations in restoration. In addition, we tested AFLP markers for signatures of selection, and examined the relationship of neutral and putatively selected markers with climate variables. Estimates of population genetic structure revealed significant levels of differentiation (ΦPT = 0.23) and suggested a global provenance distance of 45 km for pairwise comparisons of 16 populations. Of the 134 markers, 13 exhibited evidence of diversifying selection (ΦPT = 0.52). Using data for precipitation and thermal gradients, we compared genetic, geographic and environmental distance for subsets of neutral and selected markers. Strong isolation by distance was detected in all cases, but positive correlations with climate variables were present only for markers with signatures of selection. We address findings in light of defining local provenance in ecological restoration.

  5. Colonization of spinach by Verticillium dahliae and effects of pathogen localization on the efficacy of seed treatments.

    PubMed

    Maruthachalam, Karunakaran; Klosterman, Steven J; Anchieta, Amy; Mou, Beiquan; Subbarao, Krishna V

    2013-03-01

    Verticillium wilt on spinach (Spinacia oleracea) is caused by the soilborne fungus Verticillium dahliae. The pathogen is seedborne and transmission through seed is a major concern because of the dispersal of the pathogen to areas where fresh and processing spinach crops are grown in rotation with susceptible crops. Reduction in seedborne inoculum minimizes pathogen spread; therefore, knowledge of pathogen localization in seed is critical to develop methods to reduce seedborne inoculum. Spinach seedlings were inoculated with conidial suspensions of a green fluorescent protein-tagged strain of V. dahliae and colonization events were followed through seed production by confocal laser-scanning microscopy. Between 24 to 96 h postinoculation (PI), conidia germinated and formed hyphal colonies on root tips and in root elongation zones. Hyphae colonized root cortical tissues both intra and intercellularly by 2 weeks, and colonized the taproot xylem with abundant mycelia and conidia that led to vascular discoloration coincident with foliar symptom expression by 8 weeks PI. At 10 weeks PI, the xylem of the upper stem, inflorescence, and spinach seed parts, including the pericarp, seed coat, cotyledons, and radicle, had been colonized by the pathogen but not the perisperm (the diploid maternal tissue). Maximum concentration of the fungus was in the seed coat, the outermost layer of the vasculature. Infection of V. dahliae in spinach seed was systemic and transmissible to developing seedlings. Additional analyses indicated that fungicide and steam seed treatments reduced detectable levels of the pathogen but did not eliminate the pathogen from the seed. This information will assist in the development of seed treatments that will reduce the seedborne inoculum transmission to crop production fields.

  6. Biotin radioligand assay with an /sup 125/I-labeled biotin derivative, avidin, and avidin double-antibody reagents

    SciTech Connect

    Livaniou, E.; Evangelatos, G.P.; Ithakissios, D.S.

    1987-11-01

    We describe a new radioligand assay for determining biotin in biological fluids by using a mixture of N-(beta-(4-OH-3-125I-phenyl)ethyl)- and N-(beta-(4-OH-3,5-di-125I-phenyl)ethyl)biotinamides as radiotracer, avidin as a binding protein, and an avidin double-antibody as a separation reagent. The radiotracer is synthesized by coupling (at pH 8.5, 20-22 degrees C, 90 min) N-hydroxysuccinimidobiotin to radioiodinated tyramine. The assay curve is linear and the assay itself is sensitive (less than 10 ng/L), reproducible (intra- and interassay CVs 4.1% and 7.0%, respectively), and allows the simultaneous handling of more than 100 samples in less than 4 h. Serum samples from apparently normal subjects contained 100-840 ng of biotin per liter (mean 340 ng/L). Pregnant women had low concentrations of biotin (100-300 ng/L) in their serum. Patients undergoing chronic hemodialysis treatment showed high concentrations (0.5-3.0 micrograms/L), which may be ascribable to the inability of avidin, which was used as the assay binding protein, to distinguish biotin from biotinyl derivatives with an intact ureido ring.

  7. Prenatal nicotine exposure: effects on locomotor activity and central [125I]alpha-BT binding in rats.

    PubMed

    Tizabi, Y; Russell, L T; Nespor, S M; Perry, D C; Grunberg, N E

    2000-07-01

    Maternal smoking during pregnancy or in utero exposure of the fetus to nicotine may result in learning difficulties and hyperactivity in the child. To elucidate possible involvement of the alpha(7) nicotinic receptor subtype in these behavioral impairments, pregnant dams were treated with nicotine (9 mg/kg/day) via osmotic minipumps throughout gestation. Male offspring were weaned at postnatal day 18, and were tested for locomotor activity at postnatal days 20-24. Pups were sacrificed on postnatal day 36-38 and 18 discrete brain areas were analyzed for [125I]alpha-bungarotoxin (alpha-BT) binding by quantitative autoradiography. Prenatal nicotine caused an elevation in locomotor activity (vertical movements) in offspring. [125I]alpha-BT binding was significantly reduced in the hippocampal CA1 region (29%), dentate gyrus (22%), and medial geniculate nucleus (29%). These findings suggest that some of the behavioral abnormalities induced by prenatal nicotine exposure may be due to a reduction of alpha(7) nicotinic receptors in discrete brain regions.

  8. Studies with doxazosin on the saturable binding of /sup 125/I-LDL by liver in normocholesterolemic mice

    SciTech Connect

    Nanjee, M.N.; Miller, N.E.

    1987-01-01

    Tissue culture studies have provided evidence that alpha 1-adrenergic receptor inhibition with doxazosin increases the number of low-density lipoprotein (LDL) receptors in human fibroblasts. A similar effect occurring in vivo might explain the reduction of plasma LDL concentration observed in some clinical trials of prazosin. In order to examine this question further, mice were given doxazosin 100 or 400 micrograms/kg/day by i.p. injection for 4 days, after which they were killed, blood was collected and livers were excised. Binding of /sup 125/I-labelled human LDL to tissue homogenates, over the concentration range 30-120 micrograms LDL protein/ml, was measured at 37 degrees C in the absence and presence of excess unlabelled LDL. Woolf plots of the results for saturable binding were found to be compatible with a single class of binding site. In control animals Bmax for this receptor was 867 +/- 117 ng LDL protein/mg tissue protein, and the equilibrium dissociation constant was 32.7 +/- 6.6 micrograms LDL protein/ml (mean +/- SD, n = 5). Doxazosin treatment had no effect on either parameter of /sup 125/I-LDL binding. A trend towards a decrease in liver triglyceride concentration with increasing doses of doxazosin was recorded, but there was no evidence for effects on liver cholesterol or serum lipid concentrations.

  9. Autoradiographic evidence for two classes of mu opioid binding sites in rat brain using (/sup 125/I)FK33824

    SciTech Connect

    Rothman, R.B.; Jacobson, A.E.; Rice, K.C.; Herkenham, M.

    1987-11-01

    Previous studies demonstrated that pretreatment of brain membranes with the irreversible mu antagonist, beta-funaltrexamine (beta-FNA), partially eliminated mu binding sites (25,35), consistent with the existence of two mu binding sites distinguished by beta-FNA. This paper tests the hypothesis that the FNA-sensitive and FNA-insensitive mu binding sites have different anatomical distributions in rat brain. Prior to autoradiographic visualization of mu binding sites, (/sup 3/H)oxymorphone, (/sup 3/H)D-ala2-MePhe4, Gly-ol5-enkephalin (DAGO), and (/sup 125/I)D-ala2-Me-Phe4-met(o)-ol)enkephalin (FK33824) were shown to selectively label mu binding sites using slide mounted sections of molded minced rat brain. As found using membranes, beta-FNA eliminated only a portion of mu binding sites. Autoradiographic visualization of mu binding sites using the mu-selective ligand (/sup 125/I)FK33824 in control and FNA-treated sections of rat brain demonstrated that the proportion of mu binding sites sensitive to beta-FNA varied across regions of the brain, particularly the dorsal thalamus, ventrobasal complex and the hypothalamus, providing anatomical data supporting the existence of two classes of mu binding sites in rat brain.

  10. A sup 125 I-radioimmunoassay for measuring androstenedione in serum and in blood-spot samples from neonates

    SciTech Connect

    Thomson, S.; Wallace, A.M.; Cook, B. )

    1989-08-01

    We developed a radioimmunoassay with a gamma-emitting radioligand to measure androstenedione in human serum and in dried blood-spot samples from newborns. Antisera were raised in rabbits against androstenedione linked to bovine serum albumin at positions 3, 6, or 11 on the steroid nucleus. Radioligands were prepared by linking ({sup 125}I)iodohistamine at positions 3, 6, or 11. Linkages were through either carboxymethyloxime or hemisuccinate bridges. All label and antibody combinations were examined, and the most sensitive and specific combination (antiserum raised against androstenedione-3-carboxymethyloxime-bovine serum albumin with an androstenedione-carboxymethyloxime-({sup 125}I)iodohistamine label) was selected for full evaluation. We report the performance of these selected reagents in an immunoassay for androstenedione in both serum and dried blood-spot samples from neonates. We measured concentrations of androstenedione in serum under normal and pathological conditions such as congenital adrenal hyperplasia and polycystic ovarian disease. Diurnal variation in normal men was observed. Androstenedione was measured in blood spots from neonates born at term or prematurely, with respiratory distress syndrome, or with congenital adrenal hyperplasia.

  11. Radioimmunoanalysis of delta-9-THC in blood by means of an /sup 125/I tracer. [Delta-9-Tetrahydrocannabinol

    SciTech Connect

    Owens, S.M.; McBay, A.J.; Reisner, H.M.

    1982-01-01

    A radioimmunoassay for delta-9-THC in plasma, whole blood, or hemolyzed blood specimens has been presented. Samples and standards were diluted with methanol and centrifuged. An aliquot of the supernatant fluid was incubated with RIA buffer, /sup 125/I-labeled delta-8-THC and rabbit anti-THC serum. Solid phase goat anti-rabbit immunoglobulins were added to separate bound from free THC. After centrifugation the supernatant fluid was aspirated and the radioactivity of the precipitate was counted in a gamma counter. The concentration of THC was calculated from a standard curve using the logit-log transformation of the average counts of duplicate tubes. The assay had several advantages. Methanol dilution gave better results than direct analysis. The /sup 125/I-labeled THC had high specific activity and could be counted in a gamma counter. The immunological separation of antibody-bound THC from free THC was better than separation techniques using ammonium sulfate and activated charcoal. THC was determined in 0.1 ml of sample with a sensitivity of 1.5 ng/ml in plasma and 3.0 ng/ml in hemolyzed blood.

  12. 125I-labeled peptide mapping of some heat-modifiable proteins of the gonococcal outer membrane.

    PubMed Central

    Swanson, J

    1980-01-01

    Gonococci from opaque colonies have cell wall outer membrane proteins that are lacking from organisms which form transparent colonies. These "colony opacity-associated" proteins are among a group of "minor" proteins that exhibit heat modification of their apparent subunit molecular sizes, are easily extracted by deoxycholate, have apparent subunit molecular weights varying from 24,000 to 29,000 and are exposed on the surfaces of gonococci. Other minor proteins found on gonococci are the "leukocyte association proteins," whose presence correlates with reactivities of gonococci with human neutrophils. Several of the colony opacity-associated proteins and leukocyte association proteins were subjected to 125I-peptide mapping of protein bands separated by polyacrylamide electrophoresis in the presence of sodium dodecyl sulfate. The structural similarities and differences among these heat-modifiable surface proteins were studied, as well as their similarities with the major protein of the gonococcal outer membrane. A relatively high apparent degree of structural homology is found among the heat-modifiable proteins from different strains of opaque colony gonococcal forms. There is also some apparent structural homology for 125I-peptides of heat-modifiable versus major proteins of the gonococcal outer membrane. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 Fig. 6 Fig. 7 Fig. 8 PMID:6769820

  13. Inhibitory Effects of PEI-RGD/125I-(αV) ASODN on Growth and Invasion of HepG2 Cells

    PubMed Central

    Cai, Haidong; Qiao, Yu; Sun, Ming; Yuan, Xueyu; Luo, Qiong; Yang, Yuehua; Yuan, Shidong; Lv, Zhongwei

    2015-01-01

    Background To investigate the in vitro inhibitory effects of PEI-RGD/125I-(αV)ASODN (PEI, polyethylenimine; RGD, Arg-Gly-Asp; ASODN, antisense oligodeoxynucleotide) on the growth and invasion of HepG2 cells. Material/Methods ASODN of the integrin αV-subunit was marked with 125I and underwent complexation with PEI-RGD, a PEI derivative. Next, PEI-RGD/125I-(αV) ASODN was introduced into HepG2 cells via receptor-mediated transfection, and its inhibition rate on HepG2 cell growth was tested using the methyl thiazolyl tetrazolium (MTT) method. The effects of PEI-RGD/125I-(αV) ASODN on HepG2 cell invasion ability were evaluated using the Boyden chamber assay. Results 1) The 125I marking rate of (αV) ASODN was 73.78±4.09%, and the radiochemical purity was 96.68±1.38% (greater than 90% even after a 48-h incubation period at 37°C), indicating high stability. 2) The cytotoxicity assays showed that the cell inhibition rates did not differ significantly between the PEI-RGD/125I-(αV)ASODN group and the PEI-RGD/(αV) ASODN group, but they were both significantly higher than in the other groups and were positively correlated (r=0.879) with the dosage within a certain range. 3) The invasion assays showed that the inhibition rate was significantly greater in the PEI-RGD/125I-(αV) ASODN group compared to the other groups. Conclusions PEI-RGD/125I-(αV) ASODN can efficiently inhibit the growth and proliferation of HepG2 cells and can also weaken their invasive ability. PMID:26258995

  14. Tissue and Subcellular Localization of Enzymes Catabolizing (R)-Amygdalin in Mature Prunus serotina Seeds.

    PubMed

    Swain, E; Li, C P; Poulton, J E

    1992-09-01

    In black cherry (Prunus serotina Ehrh.) homogenates, (R)-amygdalin is catabolized to HCN, benzaldehyde, and d-glucose by the sequential action of amygdalin hydrolase, prunasin hydrolase, and mandelonitrile lyase. The tissue and subcellular localizations of these enzymes were determined within intact black cherry seeds by direct enzyme analysis, immunoblotting, and colloidal gold immunocytochemical techniques. Taken together, these procedures showed that the two beta-glucosidases are restricted to protein bodies of the procambium, which ramifies throughout the cotyledons. Although amygdalin hydrolase occurred within the majority of procambial cells, prunasin hydrolase was confined to the peripheral layers of this meristematic tissue. Highest levels of mandelonitrile lyase were observed in the protein bodies of the cotyledonary parenchyma cells, with lesser amounts in the procambial cell protein bodies. The residual endosperm tissue had insignificant levels of amygdalin hydrolase, prunasin hydrolase, and mandelonitrile lyase. PMID:16652960

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

    SciTech Connect

    Huang, W.Y.; Lipsey, A.I.; Cheng, M.H.

    1987-04-01

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

  16. Local Host Adaptation and Use of a Novel Host in the Seed Beetle Megacerus eulophus

    PubMed Central

    Stotz, Gisela C.; Suárez, Lorena H.; Gonzáles, Wilfredo L.; Gianoli, Ernesto

    2013-01-01

    Spatial variation in host plant availability may lead to specialization in host use and local host adaptation in herbivorous insects, which may involve a cost in performance on other hosts. We studied two geographically separated populations of the seed beetle Megacerus eulophus (Coleoptera: Bruchidae) in central Chile: a population from the host Convolvulus chilensis (in Aucó) and a population from C. bonariensis (in Algarrobo). In Aucó C. chilensis is the only host plant, while in Algarrobo both C. bonariensis and C. chilensis are available. We tested local adaptation to these native host plants and its influence on the use of another, exotic host plant. We hypothesized that local adaptation would be verified, particularly for the one-host population (Aucó), and that the Aucó population would be less able to use an alternative, high-quality host. We found evidence of local adaptation in the population from C. chilensis. Thus, when reared on C. chilensis, adults from the C. chilensis population were larger and lived longer than individuals from the C. bonariensis population, while bruchids from the two populations had the same body size and longevity when reared on C. bonariensis. Overall, bruchids from the C. chilensis population showed greater performance traits than those from the C. bonariensis population. There were no differences between the bruchid populations in their ability to use the alternative, exotic host Calystegia sepium, as shown by body size and longevity patterns. Results suggest that differences in local adaptation might be explained by differential host availability in the study populations. PMID:23326528

  17. In Vivo and In Vitro Binding of Vip3Aa to Spodoptera frugiperda Midgut and Characterization of Binding Sites by 125I Radiolabeling

    PubMed Central

    Chakroun, Maissa

    2014-01-01

    Bacillus thuringiensis vegetative insecticidal proteins (Vip3A) have been recently introduced in important crops as a strategy to delay the emerging resistance to the existing Cry toxins. The mode of action of Vip3A proteins has been studied in Spodoptera frugiperda with the aim of characterizing their binding to the insect midgut. Immunofluorescence histological localization of Vip3Aa in the midgut of intoxicated larvae showed that Vip3Aa bound to the brush border membrane along the entire apical surface. The presence of fluorescence in the cytoplasm of epithelial cells seems to suggest internalization of Vip3Aa or a fragment of it. Successful radiolabeling and optimization of the binding protocol for the 125I-Vip3Aa to S. frugiperda brush border membrane vesicles (BBMV) allowed the determination of binding parameters of Vip3A proteins for the first time. Heterologous competition using Vip3Ad, Vip3Ae, and Vip3Af as competitor proteins showed that they share the same binding site with Vip3Aa. In contrast, when using Cry1Ab and Cry1Ac as competitors, no competitive binding was observed, which makes them appropriate candidates to be used in combination with Vip3A proteins in transgenic crops. PMID:25002420

  18. Quantitative autoradiographic analysis of /sup 125/I-pindolol binding in Fischer 344 rat brain: changes in beta-adrenergic receptor density with aging

    SciTech Connect

    Miller, J.A.; Zahniser, N.R.

    1988-05-01

    Age-related changes in beta-adrenergic receptor density in Fischer 344 rat brain were examined using in vitro /sup 125/I-pindolol (IPIN) binding and quantitative autoradiographic analysis. Localized protein concentrations were determined using a new quantitative histological technique, and these were used to normalize the densities of receptors. Saturation binding studies in brain sections revealed 40-50% decreases in beta-adrenergic receptor density in the thalamus of 23-25-month-old and the cerebellum and brainstem of both 18-19-month-old and 23-25-month-old compared to 4-6-month-old rats. The loss of cerebellar beta-adrenergic receptors may be correlated with reports of deficits in sensitivity to beta-adrenergic-mediated transmission in the cerebellum of aged rats. No changes in specific IPIN binding with age were observed in rat cortex or hippocampus. In all areas examined no age-related differences were observed in receptor affinity. No changes in protein concentration were found in any of the areas examined in the different aged animals. These results demonstrate a region-specific loss of beta-adrenergic receptors with age in the brain of Fischer 344 rats.

  19. The use of a high-purity germanium detector for routine measurements of {sup 125}I in radiation workers

    SciTech Connect

    Kopp, P.; Bergmann, H.; Havlik, E.; Aiginger, H.; Unfried, E.; Riedlmayer, L.

    1994-12-01

    A high-purity germanium detector was calibrated for the assessment of {sup 125}I uptake in the thyroid gland of radiation workers. A cylindrical water phantom (perspex walls) with high flexibility for position and size of the thyroid was constructed. Within a massive shielding chamber built for a whole-body counter, an activity of 2.2 Bq was detectable (MDA). This is well below the very restrictive limiting value of 20 Bq for inhalation specified by Austrian law. An activity of 128 Bq was measured with a statistical uncertainty of 5% in a counting period of 10 min. Various parameters influencing the result are investigated as well as the performance of two other measurement geometries outside the shielding chamber. 13 refs., 4 figs., 2 tabs.

  20. The in vitro selective concentration of an /sup 125/I-iodinated compound in human tumor cells

    SciTech Connect

    Carpenter, R.N.; Brown, I.; Chir, B.; Mitchell, J.S.

    1983-01-01

    Uptake studies of the potential endoradiotherapeutic agent, 6-/sup 125/I-iodo-2-methyl-1,4-naphthoquinol bis(diammonium phosphate) have been carried out in vitro on a wide range of normal and malignant human cells. In general, for a standardized dose of 0.1 ..mu..Ci/ml, the uptake of the compound into normal cells was 0.0015-0.135 pCi/cell. Uptake into malignant cells was significantly higher than normal cells; uptakes of 0.89-11.3 pCi/cell were noted for melanoma, teratoma of testis, osteosarcoma and adenocarcinoma of colon and pancreas. Comparative uptake ratios for melanoma:Chang liver cells and testicular teratoma:normal testis were 29 and 23, respectively. Larger uptake ratios are usually observed with higher doses.

  1. With or without a Script? Comparing Two Styles of Participatory Video on Enhancing Local Seed Innovation System in Bangladesh

    ERIC Educational Resources Information Center

    Chowdhury, Ataharul Huq; Odame, Helen Hambly; Hauser, Michael

    2010-01-01

    Recent experiences in participatory video-making raise the question of how best to use this medium for enhancing local seed innovation systems. Embedded in a mini-process of participatory action research, two styles of participatory video--scripted and scriptless--were tested and assessed together with farmers and facilitators in Bogra District,…

  2. Long-term controlled release of 125I-tagged BMP-2 by mesoporous bioactive glass with ordered nanopores

    PubMed Central

    ZHANG, QUAN; ZHANG, YE; CHEN, WENJUN; ZHANG, BINGWEN; WANG, SHILONG

    2013-01-01

    The aim of this study was to investigate the ability of mesoporous bioactive glass with ordered nanopores (80S MBG) to adsorb and provide the delayed release of 125I-tagged bone morphogenetic protein-2 (BMP-2). A 50 mg piece of 80S MBG was produced, which comprised SiO2, CaO and P2O5 in a component molar ratio of 80:15:5. Each MBG piece adsorbed 30 μg 125I-BMP-2. Persistent radioactivity in the MBG was periodically measured in simulated body fluid. The total amount of BMP-2 released and the mean amount released per day were calculated. A delayed release curve of BMP-2 was constructed. SPSS 15.0 software was used to perform a statistical analysis. The amount of BMP-2 released in the first two days was one-quarter of the total load. A line equation, y = 490.55×1/2 + 7268.82, was obtained from the square root of protein release doses value at 3–94 days. The total amount of BMP-2 released over 94 days was 11.894 μg, which was ~39.6% of the total load. The half-life of the release time was 248 days. From the second week, the rate of BMP release had stabilized to a mean of 37.42±18.67 ng/day and the difference of the mean amount released per day had no statistical significance (P>0.05). High adsorption and delayed release effects of BMP-2 were observed in 80S MBG. The delayed release conforms to the Higuchi equation, which indicates possible applications in promoting bone healing. PMID:24250724

  3. A microfluidic localized, multiple cell culture array using vacuum actuated cell seeding: integrated anticancer drug testing.

    PubMed

    Gao, Yan; Li, Peng; Pappas, Dimitri

    2013-12-01

    In this study, we introduced a novel and convenient approach to culture multiple cells in localized arrays of microfluidic chambers using one-step vacuum actuation. In one device, we integrated 8 individually addressable regions of culture chambers, each only requiring one simple vacuum operation to seed cell lines. Four cell lines were seeded in designated regions in one device via sequential injection with high purity (99.9 %-100 %) and cultured for long-term. The on-chip simultaneous culture of HuT 78, Ramos, PC-3 and C166-GFP cells for 48 h was demonstrated with viabilities of 92 %+/-2 %, 94 %+/-4 %, 96 %+/-2 % and 97 %+/-2 %, respectively. The longest culture period for C166-GFP cells in this study was 168 h with a viability of 96 %+/-10 %. Cell proliferation in each individual side channel can be tracked. Mass transport between the main channel and side channels was achieved through diffusion and studied using fluorescein solution. The main advantage of this device is the capability to perform multiple cell-based assays on the same device for better comparative studies. After treating cells with staurosporine or anti-human CD95 for 16 h, the apoptotic cell percentage of HuT 78, CCRF-CEM, PC-3 and Ramos cells were 36 %+/-3 %, 24 %+/-4 %, 12 %+/-2 %, 18 %+/-4 % for staurosporine, and 63 %+/-2 %, 45 %+/-1 %, 3 %+/-3 %, 27 %+/-12 % for anti-human CD95, respectively. With the advantages of enhanced integration, ease of use and fabrication, and flexibility, this device will be suitable for long-term multiple cell monitoring and cell based assays.

  4. Preliminary Characterization and In Vivo Studies of Structurally Identical 18F- and 125I-Labeled Benzyloxybenzenes for PET/SPECT Imaging of β-Amyloid Plaques

    PubMed Central

    Yang, Yanping; Zhang, Xiaoyang; Cui, Mengchao; Zhang, Jinming; Guo, Zhide; Li, Yesen; Zhang, Xianzhong; Dai, Jiapei; Liu, Boli

    2015-01-01

    With the assistance of molecular docking and 3D-QSAR models established previously, structurally identical 18F- and 125I-labeled benzyloxybenzene derivatives were designed to achieve the early detection of Aβ plaques by PET/SPECT imaging. In competition binding assay, ligands 7a and 12a displayed high binding affinities to Aβ42 aggregates with Ki values of 19.5 nM and 23.9 nM, respectively. Specific plaque labeling was observed on the in vitro autoradiography of brain sections from AD patients and Tg mice. In biodistribution, [125I]7a, [18F]7a, [125I]12a and [18F]12a all exhibited high initial brain uptakes (>5% ID/g at 2 min). [125I]7a and [125I]12a cleared fast from the normal brain regions, while corresponding [18F]7a and [18F]12a showed slow washout rates. Dynamic microPET/CT and microSPECT/CT imaging data in normal ICR mice were in accordance with in vivo biodistribution results. In vivo metabolism results indicated that the different clearance profiles between the structurally identical 18F- and 125I-labeled tracers could be attributed to different biochemical characteristics of the radiometabolites. Radioiodinated benzyloxybenzene derivatives exhibited good in vivo biostability in brain. Ex vivo autoradiography further confirmed the strong in vivo Aβ labeling ability of [125I]7a. These new fluorinated and iodinated benzyloxybenzenes can develop into PET/SPECT dual imaging agents targeting Aβ plaques. PMID:26170205

  5. Inhibition of sup 125 I organification and thyroid hormone release by interleukin-1, tumor necrosis factor-alpha, and interferon-gamma in human thyrocytes in suspension culture

    SciTech Connect

    Sato, K.; Satoh, T.; Shizume, K.; Ozawa, M.; Han, D.C.; Imamura, H.; Tsushima, T.; Demura, H.; Kanaji, Y.; Ito, Y. )

    1990-06-01

    To elucidate the mechanism of decreased 131I uptake by the thyroid gland in patients with subacute thyroiditis and painless thyroiditis, human thyroid follicles were cultured with interleukin-1 (IL-1), tumor necrosis factor-alpha (TNF alpha), and/or interferon-gamma (IFN gamma), and the effects of these cytokines on thyroid function were studied in vitro. When human thyrocytes were cultured in RPMI-1640 medium containing 0.5% fetal calf serum and TSH for 5-8 days, the cells incorporated 125I, synthesized de novo (125I)iodotyrosines and (125I)iodothyronines, and secreted (125I)T4 and (125I)T3 into the medium. IL-1 alpha and IL-1 beta inhibited 125I incorporation and (125I)iodothyronine release in a concentration-dependent manner. The minimal inhibitory effect was detected at 10 pg/ml. Electron microscopic examination revealed a marked decrease in lysosome formation in IL-1-treated thyrocytes. TNF alpha and IFN gamma also inhibited thyroid function in a concentration-dependent manner. Furthermore, when thyrocytes were cultured with IL-1, TNF alpha and IFN gamma, these cytokines more than additively inhibited thyroid function. Although the main mechanism of 131I uptake suppression in the thyroid gland in subacute thyroiditis is due to cellular damage and suppression of TSH release, our present findings suggest that IL-1, TNF alpha, and IFN gamma produced in the inflammatory process within the thyroid gland further inhibit iodine incorporation and at least partly account for the decreased 131I uptake by the thyroid gland in destruction-induced hyperthyroidism.

  6. Purification and characterization of (-)(/sup 125/I)hydroxyphenylisopropyladenosine, an adenosine R-site agonist radioligand and theoretical analysis of mixed stereoisomer radioligand binding

    SciTech Connect

    Linden, J.

    1984-11-01

    (-)-N6-(R-4-Hydroxyphenylisopropyl)adenosine (HPIA) was iodinated with NaI and trace /sup 125/I. Mono- and diiodinated reaction products and the starting material were separated by high pressure liquid chromatography and the structures of the reaction products were verified by NMR. (-)-N6-(R-Phenylisopropyl)adenosine (PIA), IHPIA, and I2HPIA decreased rat atrial contractility with ED50 values of 24, 28, and 33 nM, respectively. The contractile effects of these compounds were competitively blocked by theophylline (KI . 7.9 microM), but were not affected by adenosine deaminase. IHPIA also inhibited (-)isoproterenol-stimulated cyclic AMP accumulation in adipocytes with an ED50 (10 nM) and to an extent (83%) nearly identical to PIA. (/sup 125/I)HPIA prepared using carrier-free /sup 125/I bound to adenosine receptors on membranes from rat cerebral cortex, adipocyte ghosts, and heart ventricles. Binding was inhibited stereospecifically by PIA and by other adenosine analogues and alkylxanthines. The KD of (/sup 125/I)HPIA determined kinetically using brain membranes at 21 degrees was 0.94 nM in good agreement with the equilibrium determination of 1.94 nM. The density of adenosine receptors in brain membranes was found to be 871 fmol/mg of protein. When normalized to protein, the density of receptors in heart membranes and adipocyte ghosts, respectively, was found to be 39- and 2.3-fold less than in brain membranes. It was concluded that (/sup 125/I)HPIA can be rapidly synthesized and purified, binds to adenosine R-sites and is an agonist radioligand resistant to adenosine deaminase. Computer modeling of the equilibrium binding resulting from the use of mixed stereoisomers of a radioligand indicates that the combined use of (-)(/sup 125/I)HPIA and (+)(/sup 125/I)HPIA would result in the generation of nonlinear Scatchard plots.

  7. Antihypertensive activity of transgenic rice seed containing an 18-repeat novokinin peptide localized in the nucleolus of endosperm cells.

    PubMed

    Wakasa, Yuhya; Zhao, Hui; Hirose, Sakiko; Yamauchi, Daiki; Yamada, Yuko; Yang, Lijun; Ohinata, Kousaku; Yoshikawa, Masaaki; Takaiwa, Fumio

    2011-09-01

    Novokinin (Arg-Pro-Leu-Lys-Pro-Trp, RPLKPW) is a new potent antihypertensive peptide based on the sequence of ovokinin (2-7) derived from ovalbumin. We previously generated transgenic rice seeds in which eight novokinin were fused to storage protein glutelins (GluA2 and GluC) for expression. Oral administration of these seeds to spontaneously hypertensive rats (SHRs) reduced systolic blood pressures at a dose of 1 g seed/kg of SHR. Here, 10- or 18-tandem repeats of novokinin with an endoplasmic reticulum (ER) retention signal (Lys-Asp-Glu-Leu, KDEL) at the C terminus were directly expressed in rice under the control of the glutelin promoter containing its signal peptide. Only small amounts of the 18-repeat novokinin accumulated, and it was unexpectedly deposited in the nucleolus. This abnormal intracellular localization was explained by an endogenous signal for nuclear localization. The GFP reporter protein fused to this sequence targeted to nuclei by a transient assay using onion epidermal cells. Transgenic seed expressing the 18-repeat novokinin exhibited significantly higher antihypertensive activity after a single oral dose to SHR even at one-quarter the amount (0.25 g/kg) of the transgenic rice seed expressing the fusion construct; though, its novokinin content was much lower (1/5). Furthermore, in a long-term administration for 5 weeks, even a smaller dose (0.0625 g/kg) of transgenic seeds could confer antihypertensive activity. This high antihypertensive activity may be attributed to differences in digestibility of expressed products by gastrointestinal enzymes and the unique intracellular localization. These results indicate that accumulation of novokinin as a tandemly repeated structure in transgenic rice is more effective than as a fusion-type structure. PMID:21078052

  8. Implication of the visual system in the regulation of activity cycles in the absence of solar light: 2-[125I]iodomelatonin binding sites and melatonin receptor gene expression in the brains of demersal deep-sea gadiform fish

    PubMed Central

    Priede, I. G.; Williams, L. M.; Wagner, H.-J.; Thom, A.; Brierley, I.; Collins, M. A.; Collin, S. P.; Merrett, N. R.; Yau, C.

    1999-01-01

    Relative eye size, gross brain morphology and central localization of 2-[125I]iodomelatonin binding sites and melatonin receptor gene expression were compared in six gadiform fish living at different depths in the north-east Atlantic Ocean: Phycis blennoides (capture depth range 265 to 1260 m), Nezumia aequalis (445 to 1512 m), Coryphaenoides rupestris (706 to 1932 m), Trachyrincus murrayi (1010 to 1884 m), Coryphaenoides guentheri (1030 m) and Coryphaenoides (Nematonurus) armatus (2172 to 4787 m). Amongst these, the eye size range was 0.15 to 0.35 of head length with a value of 0.19 for C. (N.) armatus, the deepest species. Brain morphology reflected behavioural differences with well-developed olfactory regions in P. blennoides, T. murrayi and C. (N.) armatus and evidence of olfactory deficit in N. aequalis, C. rupestris and C. guentheri. All species had a clearly defined optic tectum with 2-[125I]iodomelatonin binding and melatonin receptor gene expression localized to specific brain regions in a similar pattern to that found in shallow-water fish. Melatonin receptors were found throughout the visual structures of the brains of all species. Despite living beyond the depth of penetration of solar light these fish have retained central features associated with the coupling of cycles of growth, behaviour and reproduction to the diel light–dark cycle. How this functions in the deep sea remains enigmatic.

  9. Measurement of cyclosporine concentrations in whole blood: HPLC and radioimmunoassay with a specific monoclonal antibody and /sup 3/H- or /sup 125/I-labeled ligand compared

    SciTech Connect

    Wolf, B.A.; Daft, M.C.; Koenig, J.W.; Flye, M.W.; Turk, J.W.; Scott, M.G.

    1989-01-01

    We compared cyclosporine concentrations in whole blood as measured by HPLC and by RIA with a monoclonal antibody specific for cyclosporine with /sup 3/H- or /sup 125/I-labeled cyclosporine ligand. The /sup 3/H-RIA kit slightly underestimated cyclosporine concentrations (greater than 600 micrograms/L) in comparison with HPLC. Over a wide range of concentrations, cyclosporine measured with the /sup 125/I-RIA kit correlated well with HPLC (slope = 0.99, n = 301, r = 0.98), observed for samples from recipients of kidney, heart, or liver allografts (respective slopes: 1.01, 0.93, and 1.00). The /sup 125/I-RIA standard curve was linear to 1000 micrograms of cyclosporine per liter. Inter- and intra-assay CVs for /sup 125/I-RIA measurements of cyclosporine were less than or equal to 7%. Evidently, the /sup 125/I-RIA kit involving a monoclonal antibody specific for cyclosporine is equivalent to the HPLC assay and can replace it for therapeutic drug monitoring of cyclosporine therapy.

  10. Formation of complexes between 125I-labelled human or bovine somatotropins and binding proteins in vivo in rat liver and kidney.

    PubMed Central

    Bonifacino, J S; Roguin, L P; Paladini, A C

    1983-01-01

    At 5 min after intravenous injection, both 125I-labelled human somatotropin and 125I-labelled bovine somatotropin were concentrated in rat liver and kidney. When the labelled hormones were administered along with an excess of the corresponding unlabelled hormone, a significant decrease of the uptake was observed in the liver, but not in the kidney. Study of the subcellular distribution of radioiodinated somatotropins in liver revealed that most of the radioactivity was specifically concentrated in the microsomal fraction. In contrast, the kidney fraction that accounted for most of the radioactivity was the 100 000 g supernatant. After solubilization, with 1% (w/v) Triton X-100, of the microsomal fractions obtained from both organs, the radioactive material was analysed by gel filtration on Sepharose CL-6B. By using this approach, it was demonstrated that both 125I-labelled human somatotropin and 125I-labelled bovine somatotropin bind in vivo to proteins present in liver. A small proportion of 125I-labelled human somatotropin was also shown to form complexes with proteins present in kidney. The present results demonstrate that the liver uptake is mainly due to binding of somatotropins to specific proteins, in contrast with the kidney, in which binding to specific sites contributes minimally to the overall uptake. PMID:6615460

  11. Characterization of specific /sup 125/I-bolton hunter (BH)-CCK-8 binding in guinea pig stomach muscle membranes - similar to pancreas but different from gastric glands

    SciTech Connect

    Chang, R.S.L.; Lotti, V.J.; Chen, T.B.; Kunkel, K.K.

    1986-03-01

    Cholecystokinin (CCK) is a gastrointestinal hormone which regulates gastric motility. The authors have characterized specific /sup 125/I-BH-CCK-8 binding in guinea pig stomach muscle membranes. The relative potencies of various CCK related peptides to inhibit specific /sup 125/I-CCK-8 binding in stomach muscle membranes resembled their rank order determined for pancreatic CCK receptor binding (CCK-8>> CCK-8-desulfate = gastrin CCK-4). The specific peripheral CCK antagonist, asperlicin and other non- selective CCK antagonists including proglumide, CBZ-CCK (26-32) amide, dibutyrylcyclic GMP and benzotript effectively inhibited /sup 125/I-CCK-8 binding in gastric muscle membranes with IC/sub 50/'s comparable to those for pancreatic CCK receptors. In contrast, specific /sup 125/I-CCK-8 binding in guinea pig gastric glands was inhibited equally well by gastrin and CCK-8. Moreover, asperlicin did not inhibit /sup 125/I-CCK-8 binding in guinea gastric glands. These results indicate CCK receptors in the stomach muscle membranes are similar to pancreatic CCK receptors but different from brain CCK or gastrin receptors.

  12. Clinical application and validation of an iterative forward projection matching algorithm for permanent brachytherapy seed localization from conebeam-CT x-ray projections

    SciTech Connect

    Pokhrel, Damodar; Murphy, Martin J.; Todor, Dorin A.; Weiss, Elisabeth; Williamson, Jeffrey F.

    2010-09-15

    Purpose: To experimentally validate a new algorithm for reconstructing the 3D positions of implanted brachytherapy seeds from postoperatively acquired 2D conebeam-CT (CBCT) projection images. Methods: The iterative forward projection matching (IFPM) algorithm finds the 3D seed geometry that minimizes the sum of the squared intensity differences between computed projections of an initial estimate of the seed configuration and radiographic projections of the implant. In-house machined phantoms, containing arrays of 12 and 72 seeds, respectively, are used to validate this method. Also, four {sup 103}Pd postimplant patients are scanned using an ACUITY digital simulator. Three to ten x-ray images are selected from the CBCT projection set and processed to create binary seed-only images. To quantify IFPM accuracy, the reconstructed seed positions are forward projected and overlaid on the measured seed images to find the nearest-neighbor distance between measured and computed seed positions for each image pair. Also, the estimated 3D seed coordinates are compared to known seed positions in the phantom and clinically obtained VariSeed planning coordinates for the patient data. Results: For the phantom study, seed localization error is (0.58{+-}0.33) mm. For all four patient cases, the mean registration error is better than 1 mm while compared against the measured seed projections. IFPM converges in 20-28 iterations, with a computation time of about 1.9-2.8 min/iteration on a 1 GHz processor. Conclusions: The IFPM algorithm avoids the need to match corresponding seeds in each projection as required by standard back-projection methods. The authors' results demonstrate {approx}1 mm accuracy in reconstructing the 3D positions of brachytherapy seeds from the measured 2D projections. This algorithm also successfully localizes overlapping clustered and highly migrated seeds in the implant.

  13. Synthesis and evaluation of an (125)I-labeled azide prosthetic group for efficient and bioorthogonal radiolabeling of cyclooctyne-group containing molecules using copper-free click reaction.

    PubMed

    Choi, Mi Hee; Shim, Ha Eun; Nam, You Ree; Kim, Hye Rim; Kang, Jung Ae; Lee, Dong-Eun; Park, Sang Hyun; Choi, Dae Seong; Jang, Beom-Su; Jeon, Jongho

    2016-02-01

    Herein we report the radiosynthesis of a pyridine derived azide prosthetic group for iodine radioisotope labeling of dibenzocyclooctyne (DBCO) conjugated molecules. The radiolabeling of the stannylated precursor 2 was conducted using [(125)I]NaI and chloramine-T to give (125)I-labeled azide ([(125)I]1) with high radiochemical yield (72±8%, n=4) and radiochemical purity (>99%). Using (125)I-labeled azide ([(125)I]1), cyclic RGD peptide and near infrared fluorescent molecule were efficiently labeled with modest to good radiochemical yields. The biodistribution study and SPECT/CT images showed that [(125)I]1 underwent rapid renal clearance. These results clearly demonstrated that [(125)I]1 could be used as an useful radiotracer for in vivo pre-targeted imaging as well as efficient in vitro radiolabeling of DBCO containing molecules. PMID:26748695

  14. Localization of Lipoxygenases 1 and 2 in Germinating Soybean Seeds by an Indirect Immunofluorescence Technique 1

    PubMed Central

    Vernooy-Gerritsen, Marjan; Bos, Adri L. M.; Veldink, Gerrit A.; Vliegenthart, Johannes F. G.

    1983-01-01

    Lipoxygenases 1 and 2 were localized in etiolated germinating soybean seeds (Glycine max [L.]. Merr. var. Williams) by an indirect immunofluorescence staining technique. Sections of paraffin-embedded seedlings were stained with affinity-purified antibodies directed against lipoxygenase 1 or 2. The specificity of the immunofluorescence technique was examined by use of nonimmune serum or immunoglobulin G preparations after total adsorption with the appropriate lipoxygenase coupled to Sepharose 4B. After immunofluorescence staining with antilipoxygenase 1 or 2 IgG storage tissues of cotyledons fluoresce strongly the first days of germination. After 3 days, the abaxial hypodermis, the epidermis, and the vascular bundle sheaths show fluorescence, especially after incubation with antilipoxygenase 2 IgG. Fluorescence in cortex and pith of the hypocotyl migrates to the vascular cylinder during germination. In primary leaves, all tissues show fluorescence after 1 day of germination. In storage tissues of cotyledons, cytoplasm around the protein bodies fluoresces, whereas in other tissues protein bodies or other large cell organelles fluoresce. It is reasonable to suggest that lipoxygenase exerts its function in cells at the time that rigorous changes in metabolism take place, namely at the start of mobilization of reserves in storage tissues and start of biosynthesis of chloroplastids in several tissues. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 PMID:16663205

  15. Cytochemical localization of reserves during seed development in Arabidopsis thaliana under spaceflight conditions

    NASA Technical Reports Server (NTRS)

    Kuang, A.; Xiao, Y.; Musgrave, M. E.

    1996-01-01

    Successful development of seeds under spaceflight conditions has been an elusive goal of numerous long-duration experiments with plants on orbital spacecraft. Because carbohydrate metabolism undergoes changes when plants are grown in microgravity, developing seed storage reserves might be detrimentally affected during spaceflight. Seed development in Arabidopsis thaliana plants that flowered during 11 d in space on shuttle mission STS-68 has been investigated in this study. Plants were grown to the rosette stage (13 d) on a nutrient agar medium on the ground and loaded into the Plant Growth Unit flight hardware 18 h prior to lift-off. Plants were retrieved 3 h after landing and siliques were immediately removed from plants. Young seeds were fixed and processed for microscopic observation. Seeds in both the ground control and flight plants are similar in their morphology and size. The oldest seeds from these plants contain completely developed embryos and seed coats. These embryos developed radicle, hypocotyl, meristematic apical tissue, and differentiated cotyledons. Protoderm, procambium, and primary ground tissue had differentiated. Reserves such as starch and protein were deposited in the embryos during tissue differentiation. The aleurone layer contains a large quantity of storage protein and starch grains. A seed coat developed from integuments of the ovule with gradual change in cell composition and cell material deposition. Carbohydrates were deposited in outer integument cells especially in the outside cell walls. Starch grains decreased in number per cell in the integument during seed coat development. All these characteristics during seed development represent normal features in the ground control plants and show that the spaceflight environment does not prevent normal development of seeds in Arabidopsis.

  16. SU-D-201-06: Random Walk Algorithm Seed Localization Parameters in Lung Positron Emission Tomography (PET) Images

    SciTech Connect

    Soufi, M; Asl, A Kamali; Geramifar, P

    2015-06-15

    Purpose: The objective of this study was to find the best seed localization parameters in random walk algorithm application to lung tumor delineation in Positron Emission Tomography (PET) images. Methods: PET images suffer from statistical noise and therefore tumor delineation in these images is a challenging task. Random walk algorithm, a graph based image segmentation technique, has reliable image noise robustness. Also its fast computation and fast editing characteristics make it powerful for clinical purposes. We implemented the random walk algorithm using MATLAB codes. The validation and verification of the algorithm have been done by 4D-NCAT phantom with spherical lung lesions in different diameters from 20 to 90 mm (with incremental steps of 10 mm) and different tumor to background ratios of 4:1 and 8:1. STIR (Software for Tomographic Image Reconstruction) has been applied to reconstruct the phantom PET images with different pixel sizes of 2×2×2 and 4×4×4 mm{sup 3}. For seed localization, we selected pixels with different maximum Standardized Uptake Value (SUVmax) percentages, at least (70%, 80%, 90% and 100%) SUVmax for foreground seeds and up to (20% to 55%, 5% increment) SUVmax for background seeds. Also, for investigation of algorithm performance on clinical data, 19 patients with lung tumor were studied. The resulted contours from algorithm have been compared with nuclear medicine expert manual contouring as ground truth. Results: Phantom and clinical lesion segmentation have shown that the best segmentation results obtained by selecting the pixels with at least 70% SUVmax as foreground seeds and pixels up to 30% SUVmax as background seeds respectively. The mean Dice Similarity Coefficient of 94% ± 5% (83% ± 6%) and mean Hausdorff Distance of 1 (2) pixels have been obtained for phantom (clinical) study. Conclusion: The accurate results of random walk algorithm in PET image segmentation assure its application for radiation treatment planning and

  17. Mono(125I)iodo-Tyr10,MetO17)-vasoactive intestinal polypeptide. Preparation, characterization, and use for radioimmunoassay and receptor binding

    SciTech Connect

    Martin, J.L.; Rose, K.; Hughes, G.J.; Magistretti, P.J.

    1986-04-25

    Vasoactive intestinal polypeptide (VIP) was labeled with sodium (125I)iodide using the chloramine-T method and subsequently purified by reverse-phase high performance liquid chromatography.Three main 125I-labeled peaks designated A, B, and C resulted from the radioiodination and purification procedures. They were characterized by electrophoresis of tryptic fragments; Edman degradation (for Peaks A and C); enzymatic digestion to amino acids by leucine aminopeptidase, carboxypeptidase Y and Pronase; and treatment with cyanogen bromide. Peak A corresponds to VIP monoiodinated on Tyr10 and with the Met17 residue oxidized to methionine sulfoxide. This (mono(125I)iodo-Tyr10,MetO17)VIP displays the following characteristics. 1) It constitutes quantitatively the major product of the iodination procedure (62.5%); 2) it is well resolved from other labeled and unlabeled products; 3) it is stable (2 months at -20 degrees C); 4) it possesses a high specific activity (2050 Ci/mmol); 5) it maintains the biological activity of native VIP; and 6) it binds to antibody and membrane recognition sites in a specific, saturable, and reversible manner. Reduction of (mono(125I)iodo-Tyr10, Met-O17)VIP to (mono(125I)iodo-Tyr10)VIP does not improve the performance of the tracer in a radioimmunoassay. The method described in this article is simple and rapid and yields a molecular form of 125I-labeled VIP that has been fully characterized and is suitable for use in biological studies.

  18. Receptor-mediated endocytosis of insulin in lower vertebrates: internalization and intracellular processing of 125I-insulin in isolated hepatocytes of lamprey and frog.

    PubMed

    Lappova, Y L; Leibush, B N

    1995-10-01

    The binding of 125I-insulin to cellular insulin receptors and the internalization of insulin-receptor complexes have been studied in isolated hepatocytes of frog and lamprey. Two classes of binding sites (Kd 10(-9) and 10(-8) M) were found in cells of both species. The molecular weight of the insulin receptor alpha-subunit was 130 kDa in both species. Internalization of bound 125I-insulin in both species was found in the temperature range 0 to 20 degrees. Cells "loaded" with 125I-insulin were used to estimate the fate of the internalized ligand. Release of internalized ligand from frog cells increased at temperatures ranging from 0 to 20 degrees. At 0 degrees the degraded 125I-insulin was 5%, at 5 degrees 7%, and at 20 degrees 17% of total radioactivity accumulated in the medium. In lamprey hepatocytes there was neither radioactivity accumulation in the incubation medium nor release from cells at all temperatures studied. The intracellular degradation of internalized 125I-insulin in frog hepatocytes was much lower than that in lamprey cells. In frog hepatocytes the specific binding of 125I-insulin was increased twofold in the presence of the lysosomal inhibitor chloroquine. In contrast no increase was found in lamprey hepatocytes. In conclusion, the processing pathways of internalized insulin in the cells of ectothermal and endothermal vertebrates are generally similar but in ectothermal animals all events take place at lower temperatures and at lower rates. The peculiarities of insulin processing in lamprey hepatocytes most likely result from the transformation of hepatocytes during the nonfeeding prespawning period. PMID:8575649

  19. Nicotinic binding in rat brain: autoradiographic comparison of (/sup 3/H)acetylcholine, (/sup 3/H)nicotine, and (/sup 125/I)-alpha-bungarotoxin

    SciTech Connect

    Clarke, P.B.; Schwartz, R.D.; Paul, S.M.; Pert, C.B.; Pert, A.

    1985-05-01

    Three radioligands have been commonly used to label putative nicotinic cholinoceptors in the mammalian central nervous system: the agonists (/sup 3/H)nicotine and (/sup 3/H)acetylcholine ((/sup 3/H)ACh--in the presence of atropine to block muscarinic receptors), and the snake venom extract, (/sup 125/I)-alpha-bungarotoxin((/sup 125/I)BTX), which acts as a nicotinic antagonist at the neuromuscular junction. Binding studies employing brain homogenates indicate that the regional distributions of both (/sup 3/H)nicotine and (/sup 3/H)ACh differ from that of (/sup 125/I)BTX. The possible relationship between brain sites bound by (/sup 3/H)nicotine and (/sup 3/H)ACh has not been examined directly. The authors have used the technique of autoradiography to produce detailed maps of (/sup 3/H)nicotine, (/sup 3/H)ACh, and (/sup 125/I)BTX labeling; near-adjacent tissue sections were compared at many levels of the rat brain. The maps of high affinity agonist labeling are strikingly concordant, with highest densities in the interpeduncular nucleus, most thalamic nuclei, superior colliculus, medial habenula, presubiculum, cerebral cortex (layers I and III/IV), and the substantia nigra pars compacta/ventral tegmental area. The pattern of (/sup 125/I)BTX binding is strikingly different, the only notable overlap with agonist binding being the cerebral cortex (layer I) and superior colliculus. (/sup 125/I)BTX binding is also dense in the inferior colliculus, cerebral cortex (layer VI), hypothalamus, and hippocampus, but is virtually absent in thalamus. Various lines of evidence suggest that the high affinity agonist-binding sites in brain correspond to nicotinic cholinergic receptors similar to those found at autonomic ganglia; BTX-binding sites may also serve as receptors for nicotine and are possibly related to neuromuscular nicotinic cholinoceptors.

  20. High affinity binding of /sup 125/I-labeled mouse interferon to a specific cell surface receptor. II. Analysis of binding properties

    SciTech Connect

    Aguet, M.; Blanchard, B.

    1981-12-01

    Direct ligand-binding studies with highly purified /sup 125/I-labeled virus-induced mouse interferon on mouse lymphoma L 1210 cells revealed a direct correlation of specific high-affinity binding with the biologic response to interferon. Neutralization of the antiviral effect by anti-interferon gamma globulin occurred at the same antibody concentration as the inhibition of specific binding. These results suggest that specific high-affinity binding of /sup 125/I-interferon occurred at a biologically functional interferon receptor. Competitive inhibition experiments using /sup 125/I- and /sup 127/I-labeled interferon provided strong evidence that the fraction of /sup 125/I-interferon inactivated upon labeling did not bind specifically. Scatchard analysis of the binding data yielded linear plots and thus suggested that interferon binds to homogeneous noncooperative receptor sites. In contrast to a characteristic property of several peptide hormone systems, binding of /sup 125/I-interferon to its specific receptor did not induce subsequent ligand degradation. At 37/sup o/ bound interferon was rapidly released in a biologically active form without evidence for molecular degradation. The expression of interferon receptors was not modified by treatment with interferon. Trypsin treatment of target cells and inhibition of protein synthesis abolished the specific binding of /sup 125/I-interferon. Three major molecular weight species of Newcastle disease virus-induced mouse C 243 cell interferon were isolated, separated, and identified as mouse ..cap alpha.. and ..beta.. interferons. These interferons were shown to inhibit competitively the specific binding of the highly purified labeled starting material thus providing evidence for a common receptor site for mouse interferon.

  1. Autoradiographic distribution of 125I calcitonin gene-related peptide binding sites in the rat central nervous system.

    PubMed

    Skofitsch, G; Jacobowitz, D M

    1985-01-01

    Using autoradiographic method and 125I-Tyro rat CGRP as a ligand, receptor binding sites were demonstrated in the rat central nervous system. Saturation studies and Scatchard analysis of CGRP-binding to slide mounted tissue sections containing primarily cerebellum showed a single class of receptors with a dissociation constant of 0.96 nM and a Bmax of 76.4 fmol/mg protein. 125I-Tyro rat CGRP binding sites were demonstrated throughout the rat central nervous system. Dense binding was observed in the telencephalon (medial prefrontal, insular and outer layers of the temporal cortex, nucleus accumbens, fundus striatum, central and inferior lateral amygdaloid nuclei, most caudal caudate putamen, organum vasculosum laminae terminalis, subfornical organ), the diencephalon (anterior hypothalamic, suprachiasmatic, arcuate, paraventricular, dorsomedial, periventricular, reuniens, rhomboid, lateral thalamic pretectalis and habenula nuclei, zona incerta), in the mesencephalon (superficial layers of the superior colliculus, central nucleus of the geniculate body, inferior colliculus, nucleus of the fifth nerve, locus coeruleus, nucleus of the mesencephalic tract, the dorsal tegmental nucleus, superior olive), in the molecular layer of the cerebellum, in the medulla oblongata (inferior olive, nucleus tractus solitarii, nucleus commissuralis, nuclei of the tenth and twelfth nerves, the prepositus hypoglossal and the gracilis nuclei, dorsomedial part of the spinal trigeminal tract), in the dorsal gray matter of the spinal cord (laminae I-VI) and the confines of the central canal. Moderate receptor densities were found in the septal area, the "head" of the anterior caudate nucleus, medial amygdaloid and bed nucleus of the stria terminalis, the pyramidal layers of the hippocampus and dentate gyri, medial preoptic area, ventromedial nucleus, lateral hypothalamic and ventrolateral thalamic area, central gray, reticular part of the substantia nigra, parvocellular reticular nucleus

  2. Translocation of 125I, 75Se and 36Cl to wheat edible parts following wet foliar contamination under field conditions.

    PubMed

    Hurtevent, P; Thiry, Y; Levchuk, S; Yoschenko, V; Henner, P; Madoz-Escande, C; Leclerc, E; Colle, C; Kashparov, V

    2013-07-01

    Apart from radiocaesium and radiostrontium, there have been few studies on the foliar transfer of radionuclides in plants. Consequently, specific translocation factor (ftr) values for (129)I, (79)Se and (36)Cl are still missing from the IAEA reference databases. The translocation of short - lived isotopes, (125)I and (75)Se, and of (36)Cl to wheat grain were measured under field conditions following acute and chronic wet foliar contamination at various plant growth stages in the absence of leaching caused by rain. The translocation factors ranged from 0.02% to 1.1% for (125)I (a value similar to Sr), from 0.1% to 16.5% for (75)Se, and from 1% to 14.9% for (36)Cl. Both (36)Cl and (75)Se were as mobile as Cs. The phenomenological analysis showed that each element displayed a specific behavior. Iodide showed the lowest apparent mobility because of its preferential fixation in or on the leaves and a significant amount probably volatilized. Selenite internal transfer was significant and possibly utilized the sulphur metabolic pathway. However bio - methylation of selenite may have led to increased volatilization. Chloride was very mobile and quickly diffused throughout the plant. In addition, the analysis underlined the importance of plant growth responses to annual variations in weather conditions that can affect open field experiments because plant growth stage played a major role in ftr values dispersion. The chronic contamination results suggested that a series of acute contamination events had an additive effect on translocated elements. The highest translocation value obtained for an acute contamination event was shown to be a good conservative assessment of chronic contamination if data on chronic contamination translocation are lacking. The absence of rain leaching during the experiment meant that this investigation avoided potential radionuclide transfer by the roots, which also meant that radionuclide retention on or in the leaves was maximized. This study was

  3. Monte Carlo radiation dose simulations and dosimetric comparison of the model 6711 and 9011 {sup 125}I brachytherapy sources

    SciTech Connect

    Rivard, Mark J.

    2009-02-15

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

  4. /sup 125/I-Clq-binding and specific antibodies as indicators of pulmonary disease activity in cystic fibrosis

    SciTech Connect

    Moss, R.B.; Hsu, Y.P.; Lewiston, N.J.

    1981-08-01

    We studied the incidence and levels of circulating immune complexes by the /sup 125/I-Clq-binding assay in patients with cystic fibrosis in relation to clinical respiratory status and specific IgG and IgE antibodies to Pseudomonas aeruginosa. Staphylococcus aureus, Aspergillus fumigatus, and Candida albicans. Overall prevalence of CIC was 43%, but 86% of serially studied patients had evidence of CIC at some time. Patients with acute respiratory exacerbations and deteriorating pulmonary function had a higher incidence of CIC (76%) as compared to stable patients (36%, P less than 0.01), as well as significantly higher levels of CIC. Acute exacerbations were also associated with significant increases in IgG antibody to Pseudomonas (P less than 0.005) but not in other antibodies. CIC did not correlate with Pseudomonas-specific IgG nor with any other specific antibody studied. A variety of age-related differences in specific antibody levels were seen. The episodic appearance of CIC is common in CF and is usually associated with exacerbation of lung disease.

  5. /sup 125/I-labeled radioimmunoassay kits for progesterone evaluated for use in an in vitro fertilization program

    SciTech Connect

    Blight, L.F.; White, G.H.

    1983-06-01

    We have evaluated two commercially available /sup 125/I radioimmunoassay kits (Diagnostic Products Corp., DPC; and Radioassay Systems Laboratories, RSL) for measurement of serum or plasma progesterone, to determine their suitability for use in in vitro fertilization programs. Both kits were suitably rapid for program requirements. Results by both were linear with concentration up to 60 nmol/L, and both had acceptable lower detection limits of 0.3 nmol/L. Kit-determined progesterone concentrations (y) for 100 patients' samples correlated well with results by our existing 3H radioimmunoassay method (y . 1.11x + 0.2, r . 0.965 for the DPC kit; y . 1.01x + 1.4, r . 0.974 for the RSL kit). Mean analytical recovery for the RSL kit was 116%, that for the DPC kit, 202%. Within-batch precision, expressed as the mean CV for three concentrations of progesterone, was 6.5% for the RSL kit, and 16.4% for the DPC kit; between-day CV was 8.1% for the RSL kit, 17.7% for the DPC kit. We conclude that the RSL kit provides a rapid, precise, and accurate assay for serum progesterone, suitable for use in a fertilization program, but do not recommend the DPC kit for either this purpose or the more general purpose of tracking menstrual cycles.

  6. Binding of 125I-labelled fibrin(ogen) fragments to platelets and to immunoprecipitated glycoprotein IIb-IIIa complex

    SciTech Connect

    Thorsen, L.I.; Brosstad, F.; Gogstad, G.; Sletten, K.; Solum, N.O.

    1986-06-01

    To further investigate which parts of the fibrinogen molecule that are responsible for its binding to the fibrinogen receptor on human platelets, the following approaches were made: The glycoprotein IIb-IIIa complex (the putative fibrinogen receptor) was immunoprecipitated in crossed immunoelectrophoresis of Triton X-100-extracts of platelets against antibodies to whole platelet proteins. Subsequently, the immunoplates were incubated with /sup 125/I-labelled, plasmin- or CNBr-cleaved fibrinogen fragments (pre-X,X,Y,D,Degta,Efg,N-DSK) or fibrin fragments (E1,N-dsk), characterized by partial sequenation. The immunoplates were exposed to X-ray films, and binding of the fragments to the glycoprotein IIb-IIIa complex was examined. The findings were compared to the results obtained from studies on binding of the same fragments to intact gel-filtered platelets after ADP-stimulation. The following conclusions were made: All fragments except Efg and Degta bound to the immunoprecipitated GPIIb-IIIa complex as well as to ADP-stimulated platelets suggesting that at least two sequences in the E domain and one in each of the D domains of fibrinogen are involved in binding to the platelet receptor. The GPIIb-IIIa complex is the only surface-located platelet antigen that binds fibrinogen and the aforementioned fragments. The binding of the fragments to the receptor is dependent on divalent cations.

  7. Long-term follow-up after high-activity 125I brachytherapy for pediatric brain tumors.

    PubMed

    Sneed, P K; Russo, C; Scharfen, C O; Prados, M D; Malec, M K; Larson, D A; Lamborn, K R; Lamb, S A; Voss, B; Weaver, K A; Phillips, T L; Gutin, P H; Wara, W M; Edwards, M S

    1996-06-01

    A retrospective review including long-term follow-up (4.6-12.0 years) was performed of all 28 pediatric patients who underwent high-activity 125I brachytherapy at the University of California, San Francisco, for primary or recurrent brain tumors from 1980 until 1991. There were 4 glioblastomas, 11 high-grade nonglioblastoma multiforme (NGM) malignant gliomas, 10 contrast-enhancing low-grade NGM, 2 choroid plexus carcinomas, and 1 rhabdomyosarcoma. The 13 survivors included 7 of 8 patients with primary high-grade NGM, 2 of 3 patients with primary low-grade NGM, and 3 of 7 patients with recurrent low-grade NGM. Necrosis (with or without tumor) was identified in 17 of 22 reoperated patients. The mean Karnofsky performance status was 88 +/- 9 at the time of brachytherapy, 87 +/- 7 at 3 years, and 87 +/- 9 in 11 patients alive at 6-12 years. Brachytherapy is a useful modality for treating selected pediatric brain tumors, and although focal necrosis is a common sequela, it does not tend to have a major impact on the Karnofsky performance status, if the implant site is amenable to reoperation.

  8. A rapid radioimmunoassay using /sup 125/I-labeled staphylococcal protein A for antibody to varicella-zoster virus

    SciTech Connect

    Richman, D.D.; Cleveland, P.H.; Oxman, M.N.; Zaia, J.A.

    1981-05-01

    A sensitive radioimmunoassay for serum antibody to varicella-zoster virus is described; it uses 125I-labeled staphylococcal protein A and a specially designed immunofiltration apparatus. The assay accurately distinguishes between individuals who are susceptible and those who are immune to infection with varicella-zoster virus. In addition, it can detect passive antibody in recipients of varicella-zoster immune globulin. This radioimmunoassay also detects the heterologous antibody responses that occasionally occur in patients infected with herpes simplex virus, which also have been detected by other antibody assays. The particular advantages of this assay are the use of noninfectious reagents, the speed of execution (less than 3 hr), the requirement for only small quantities of serum (30 microliters), the objectivity of end-point determination, and the capability of screening large numbers of sera. Consequently, this radioimmunoassay is especially useful for the rapid identification of susceptible individuals, which is essential for the appropriate management of patients and hospital personnel after exposure to varicella.

  9. Erythropoietin messenger RNA levels in developing mice and transfer of /sup 125/I-erythropoietin by the placenta

    SciTech Connect

    Koury, M.J.; Bondurant, M.C.; Graber, S.E.; Sawyer, S.T.

    1988-07-01

    Erythropoietin (EP) mRNA was measured in normal and anemic mice during fetal and postnatal development. Normal fetal livers at 14 d of gestation contained a low level of EP mRNA. By day 19 of gestation, no EP mRNA was detected in normal or anemic fetal livers or normal fetal kidneys, but anemic fetal kidneys had low levels of EP mRNA. Newborn through adult stage mice responded to anemia by accumulating renal and hepatic EP mRNA. However, total liver EP mRNA was considerably less than that of the kidneys. Juvenile animals, 1-4 wk old, were hyperresponsive to anemia in that they produced more EP mRNA than adults. Moreover, nonanemic juveniles had readily measured renal EP mRNA, whereas the adult level was at the lower limit of detection. Because of the very low level of fetal EP mRNA, placental transfer of EP was evaluated. When administered to the pregnant mouse, /sup 125/I-EP was transferred in significant amounts to the fetuses. These results indicate that in mice the kidney is the main organ of EP production at all stages of postnatal development and that adult kidney may also play some role in providing EP for fetal erythropoiesis via placental transfer of maternal hormone.

  10. Updated Solid Water trade mark sign to water conversion factors for {sup 125}I and {sup 103}Pd brachytherapy sources

    SciTech Connect

    Meigooni, Ali S.; Awan, Shahid B.; Thompson, Nathan S.; Dini, Sharifeh A.

    2006-11-15

    Dosimetric characteristics of brachytherapy sources are normally determined in water using a Monte Carlo simulation technique and in water equivalent phantom material using both experimental and Monte Carlo simulation techniques. The consensuses of these results are then calculated for clinical applications by converting experimental data obtained in water equivalent material to water using a conversion factor. These conversion factors are normally determined as a ratio of the Monte Carlo-simulated dose rate constant in liquid water to the dose rate constant in a water-equivalent phantom material. However, it has been noted that conversion factors utilized by some investigators have been derived using incorrect phantom material composition and incorrect cross-sectional data information. The impact of errors associated with the cross-sectional data and chemical composition of the phantom material used in dosimetric evaluation of brachytherapy sources has been investigated in this project. Results of these investigations have shown that the use of Solid Water trade mark sign with 1.7% calcium content, as compared to the 2.3% value stated by the manufacturer, may lead to 5% and 9% differences in conversion factors for {sup 125}I and {sup 103}Pd, respectively.

  11. Identification of cross-reactive promastigote cell surface antigens of some leishmanial stocks by 125I labeling and immunoprecipitation.

    PubMed Central

    Gardiner, P R; Jaffe, C L; Dwyer, D M

    1984-01-01

    Externally oriented surface membrane constituents of promastigotes from several Leishmania species were radiolabeled with 125I. Autoradiographs of cell surface-labeled and sodium dodecyl sulfate-polyacrylamide gel electrophoresis-separated proteins of the stocks revealed distinctive patterns of bands in the molecular weight range of 6,000 to 240,000. Immunoprecipitation of detergent extracts of the labeled promastigote stocks with anti-Leishmania donovani membrane serum demonstrated that each of the stocks contained some antigenically cross-reactive determinants. The electrophoretic patterns of these determinants serve both to distinguish the parasite stocks (by unique, species-specific patterns) and to indicate antigenic similarities in stocks thought to be different by other biochemical criteria. At least 12 cross-reactive cell surface antigens in two New World leishmanias are recognized by polyvalent anti-L. donovani serum, suggesting that these common leishmanial antigens may account for the documented serological cross-reactivities among various Leishmania species. In all stocks tested, an iodinated protein was identified which had a relative molecular weight of 65,000 under reducing conditions but which demonstrated an increase in relative mobility in sodium dodecyl sulfate-polyacrylamide gels under nonreducing conditions. Distinctive patterns of the antigens common to the several stocks were also demonstrated with the use of monoclonal antibodies. Images PMID:6363295

  12. A rapidly produced 125I labelled autologous fibrinogen: in vitro properties and preliminary metabolic studies in man.

    PubMed Central

    Hawker, R J; Hawker, L M

    1976-01-01

    The properties of fibrinogen extracted by a precipitation method using glycine at ambient temperatures near neutral pH are described. The simple and reproducible method gives a 73% yield of high purity plasminogen-free fibrinogen in 45 minutes from small volumes of plasma. The protein extract was labelled with 125I using chloramine-T under conditions optimal for fibrinogen stability. The extraction procedure, radio-iodination, desalting, and sterilization take only 70 minutes for completion from the time donor blood is received in the laboratory. The methods, using a specially developed extraction vessel and desalting/sterilizing column, can be used in a small hospital laboratory. Autologous fibrinogen can thus be extracted from patients' blood, eliminating the risk of transmitting hepatitis when it is re-administered. The autologous material, which is 97% clottable and contains less than 0-05% free iodide, is being routinely used as a diagnostic tool in the detection of deep vein thrombosis. The high purity of the preparation facilitates metabolic studies and in vitro experimental work. In vivo results show a mean half-life in three normal volunteers of 3-95 days and a catabolic rate of 25-23% per day with the extravascular space estimated as 24-86%. In 30 surgical patients an expected reduced half-life in plasma was determined with a mean of 3-1 days. PMID:939805

  13. (125)I-spectramide: A novel benzamide displaying potent and selective effects at the D sub 2 dopamine receptor

    SciTech Connect

    Sanchez-Roa, P.M.; Grigoriadis, D.E.; Wilson, A.A.; Sharkey, J.; Dannals, R.F.; Villemagne, Victor, L.; Wong, D.F.; Wagner, H.N. Jr.; Kuhar, M.J. )

    1989-01-01

    The new substituted benzamide Spectramide, (N-(2-(4-iodobenzyl-N-methylamino)-2-methoxy-4-ethyl)-5-chloro-methylamine benzamide) labelled with {sup 125}I was used as a potent and highly selective dopamine-D{sub 2} receptor antagonist in rat striatal homogenates for in vitro receptor binding. Kinetic experiments demonstrated the reversibility of the binding and the estimated Kd from saturation analysis was 25 pM, with a Bmax of 20 pmol/g of tissue. Competition studies showed that spectramide did not interact potently with the D{sub 1} or dopamine-uptake site. Drugs known to interact with other receptor system were weak competitors of the binding, while binding was potently inhibited by other D{sub 2} antagonists, such as spiperone and eticlopride. These data indicate that Spectramide binds selectively and with high affinity to the dopamine D{sub 2} receptors, and may prove to be a useful tool for the study of these receptors in vivo using PET or SPECT.

  14. Receptor-mediated endocytosis of polypeptide hormones is a regulated process: inhibition of (125I)iodoinsulin internalization in hypoinsulinemic diabetes of rat and man

    SciTech Connect

    Carpentier, J.L.; Robert, A.; Grunberger, G.; van Obberghen, E.; Freychet, P.; Orci, L.; Gorden, P.

    1986-07-01

    Much data suggest that receptor-mediated endocytosis is regulated in states of hormone excess. Thus, in hyperinsulinemic states there is an accelerated loss of cell surface insulin receptors. In the present experiments we addressed this question in hypoinsulinemic states, in which insulin binding to cell surface receptors is generally increased. In hepatocytes obtained from hypoinsulinemic streptozotocin-induced diabetic rats, (/sup 125/I)iodoglucagon internalization was increased, while at the same time (/sup 125/I)iodoinsulin internalization was decreased. The defect in (/sup 125/I)iodoinsulin internalization was corrected by insulin treatment of the animal. In peripheral blood monocytes from patients with type I insulinopenic diabetes, internalization of (/sup 125/I)iodoinsulin was impaired; this defect was not present in insulin-treated patients. These data in the hypoinsulinemic rat and human diabetes suggest that receptor-mediated endocytosis is regulated in states of insulin deficiency as well as insulin excess. Delayed or reduced internalization of the insulin-receptor complex could amplify the muted signal caused by deficient hormone secretion.

  15. /sup 125/I-FK 33-824: a selective probe for radioautographic labeling of mu opioid receptors in the brain

    SciTech Connect

    Moyse, E.; Pasquini, F.; Quirion, R.; Beaudet, A.

    1986-03-01

    The selectivity of the Met-enkephalin analog FK 33-824 (FK) for mu opioid receptors has been, over the years, a matter of controversy. We report here pharmacological and radioautographic data demonstrating that at nanomolar concentrations. /sup 125/I-FK interacts exclusively with mu sites. (1) Specific binding of /sup 125/I-FK to rat striatal membranes is totally inhibited by mu- and/or delta-preferring ligands according to monovalent, Michaelian kinetics, with a potency proportional to the affinity of competing drugs for mu receptors. (2) Unlabeled FK competes only at high concentration with the delta-selective ligand 3H-DPLPE and according to the same kinetics as the mu-selective agonist DAGO. (3) /sup 125/I-FK generates the same regional radioautographic labeling pattern as 3H-DAGO. We conclude that when used at nanomolar concentrations /sup 125/I-FK constitutes a selective probe for the radioautographic detection of mu opioid receptors at both light and electron microscopic levels.

  16. Brain penetration of the histamine H3 receptor antagonists thioperamide and clobenpropit in rat and mouse, determined with ex vivo [125I]iodophenpropit binding.

    PubMed

    Mochizuki, T; Jansen, F P; Leurs, R; Windhorst, A D; Yamatodani, A; Maeyama, K; Timmerman, H

    1996-12-16

    We investigated the brain penetration of the histamine H3 receptor antagonists thioperamide and clobenpropit using ex vivo [125I]iodophenpropit binding. Homogenates of the rat cortex, striatum and mouse whole brain were prepared 1 h after subcutaneous injection of the H3 antagonists and incubated with [125I]iodophenpropit, a radiolabeled H3 receptor antagonist, to determine the H3 receptor occupancy. Specific [125I]iodophenpropit binding to the rat cortex and striatum was inhibited by thioperamide with IC30 values of 1.0 and 1.5 mg/kg, respectively. Clobenpropit also inhibited [125I]iodophenpropit binding, but was less potent (IC30: 18 and 19 mg/kg in the rat cortex and striatum, respectively) than thioperamide. Similar results were obtained in experiments with mouse whole brain (3.5 and 13 mg/kg for thioperamide and clobenpropit), indicating that there is no important species differences in the brain penetration of these drugs between rats and mice. These findings suggest that after peripheral injection both in rat and mouse thioperamide penetrates the blood-brain barrier more efficiently compared to clobenpropit.

  17. Two saturable recognition sites for (-) (125I)iodo-N6-(4-hydroxyphenyl-isopropyl)-adenosine binding on purified cardiac sarcolemma

    SciTech Connect

    Hausleithner, V.; Freissmuth, M.; Schuetz, W.

    1986-01-01

    Analysis of (-) (125)iodo-N6-(4-hydroxyphenylisopropyl)-adenosine (( /sup 125/I)HPIA) binding to purified sarcolemmal preparations of guinea pig and bovine hearts revealed two classes of binding sites when unlabeled iodo-HPIA (100 mumol/l) was used as non-specific binding marker. In the presence of 1 mmol/l theophylline, however, only the high affinity component was detected. Adenosine receptor agonists caused biphasic displacement of (/sup 125/I)HPIA binding, with a high affinity potency rank order typical of interaction with A1-adenosine receptors. Biphasic competition curves were also observed with 8-phenyltheophylline and isobutylmethylxanthine, whereas the theophylline curve was monophasic up to 1 mmol/l. In brain membranes, specific binding of (/sup 125/I)HPIA as well as of (/sup 3/H)PIA was further reduced when unlabeled iodo-HPIA replaces theophylline as the non-specific binding marker. These results suggest the presence of two (/sup 125/I)HPIA binding sites on cardiac sarcolemma and brain membranes, but receptor function can only be ascribed to the high affinity sites. The low affinity site probably represents an artefact, which is often observed when non-specific binding is defined with the unlabeled counterpart or a structurally related ligand of the radioligand used.

  18. /sup 125/I-Fibrin deposition in contact sensitivity reactions in the mouse. Sensitivity of the assay for quantitating reactions after active or passive sensitization

    SciTech Connect

    Mekori, Y.A.; Dvorak, H.F.; Galli, S.J.

    1986-03-15

    The clotting associated with delayed hypersensitivity (DH) responses in the mouse by sensitizing the animals to the contactant oxazolone (Ox), and then administering /sup 125/I-guinea pig fibrinogen i.v. 10 to 30 min before antigen challenge 5 days later. Early (4 to 8 hr) contact sensitivity (CS) responses in immunized mice were barely detectable by three conventional measures of CS, but the total /sup 125/I-cpm in ears challenged with hapten was 3.6 to 4.5 x that in control ears challenged with vehicle alone; moreover, the amount of urea-insoluble cpm (cross-linked /sup 125/I-fibrin-associated cpm) in the reactions to Ox was 6.5-fold to 8.2-fold that present in the control reactions. In 24 hr reactions that were near peak intensity by measurements of ear swelling, ear weight ratios, and ratios of /sup 125/I-5-iodo-2-deoxyuridine-labeled leukocyte infiltration, the cpm in antigen-challenged ears exceeded that in control ears by 13-fold to 53-fold. In addition, antigen-challenged ears contained 27 to 300 x the urea-insoluble cpm present in control ears. /sup 125/I-Fibrin deposition was not a specific characteristic of CS reactions, because a small amount of urea-insoluble reactivity was also detected in some reactions to Ox in native mice. Nevertheless, the assay was exquisitely sensitive and readily detected quantitative differences between the immunologically specific and nonspecific reactions at very early intervals after challenge or with suboptimal doses of antigen.

  19. Variation in the binding of /sup 125/I-labeled interferon-beta ser to cellular receptors during growth of human renal and bladder carcinoma cells in vitro

    SciTech Connect

    Ruzicka, F.J.; Schmid, S.M.; Groveman, D.S.; Cummings, K.B.; Borden, E.C.

    1987-09-01

    Studies of various established human bladder and renal carcinoma cell lines cultured in vitro demonstrated the presence of specific, saturable, high affinity binding sites for /sup 125/I-labeled human interferon Beta ser IFN-beta ser). This recombinant produced interferon labeled with approximately one atom of /sup 125/I/molecule of IFN expressed minimal or no loss of antiviral activity. A single class of binding sites (1000-2000/cell) with an affinity constant of 10(10)-10(11) L/M was measured at 4 degrees C for cells exhibiting widely different sensitivity to the antiproliferative effect of IFN-beta ser. Major fluctuations in the binding of /sup 125/I-labeled IFN-beta ser to cellular receptors were observed during in vitro proliferation of four of five cell lines examined. A significant decrease (P less than 0.001) in specific binding was observed 48 h after cultures were established. Cell cycle analysis suggested that within the first 24 h and in the very late log and stationary phase of growth of ACHN (human renal carcinoma) cells, variations in the binding of /sup 125/I-labeled IFN-beta ser were partially attributable to binding fluctuations during the mitotic cycle. The 2- to 3-fold decline 24 h following plating of ACHN cells corresponded to a 70% decrease in the number of cells in G0-G1. T24 (human transitional cell carcinoma) and ACHN cells, synchronized by serum starvation, demonstrated increased binding of /sup 125/I-labeled IFN-beta ser 4-16 h following serum replenishment. This increase in receptor binding occurred prior to the onset of DNA and protein synthesis and was followed by a decline immediately prior to cell division. Binding site analysis indicated that the increased binding prior to DNA synthesis was due to a 5- to 6-fold increase in receptor affinity for the radiolabeled ligand.

  20. Pilot clinical trial of 5-[{sup 125}I] iodo-2{prime}-deoxyuridine in the treatment of colorectal cancer metastic to the liver

    SciTech Connect

    Macapinlac, H.A.; Kemeny, N.; Daghighian, F.

    1996-04-01

    The thymidine analog, 5-iodo-2{prime}-deoxyuridine (IUdR), is incorporated in the DNA of cell sin the S phase. When incorporated in the DNA, short-range Auger electrons emitted by {sup 125}I-labeled IUdR can cause double-strand breaks, delivering a lethal radiation dose to the cell. We conducted therapeutic trial to evaluate [{sup 125}I/{sup 131}I]IUdR pharmacokinetics in liver metastases from colorectal cancer. Dosimetry, safety, and therapeutic potential were assessed. Four patients were each infused with 5 mCi [{sup 125}I]IUdR and 10 mCi [{sup 131}I]IUdR through the sideport of a hepatic artery pump. Iodine-131 images were quantitated and used for pharmacokinetic studies. The radioactivity in the DNA of biopsy samples of tumor, normal liver and bone marrow, obtained 24 or 48 hr after injection, was counted. All patients had [{sup 125}I]IUdR and [{sup 131}I]IUdR uptake in tumor, with a biexponential clearance. Repeat injections in individual patients showed little variation in tumor uptake, especially in the slow clearance component. On planar images, no long-term retention was seen in bone marrow or other activity dividing normal tissues. Radioactivity in the DNA of one marrow sample taken at 24 hr was above background, but in another taken at 48 hr it was equal to background levels. No side effects were noted, no hematologic toxicity was observed in any patients and no tumor responses were seen. There is persisten uptake of [{sup 125}I]IUdR in hepatic tumors, thereby making hepatic artery infusion a suitable mode of delivery for therapy. Repeat injections will be needed because only 15%-50% of tumor cells are in the S phase. Based on results from this pilot study, a therapeutic regimen is being planned. 43 refs. 2 figs.

  1. Tritiated-nicotine- and /sup 125/I-alpha-bungarotoxin-labeled nicotinic receptors in the interpeduncular nucleus of rats. II. Effects of habenular destruction

    SciTech Connect

    Clarke, P.B.; Hamill, G.S.; Nadi, N.S.; Jacobowitz, D.M.; Pert, A.

    1986-09-15

    The cholinergic innervation of the interpeduncular nucleus (IPN) is wholly extrinsic and is greatly attenuated by bilateral habenular destruction. We describe changes in the labeling of putative nicotinic receptors within this nucleus at 3, 5, or 11 days after bilateral habenular lesions. Adjacent tissue sections of the rat IPN were utilized for /sup 3/H-nicotine and /sup 125/I-alpha-bungarotoxin (/sup 125/I-BTX) receptor autoradiography. Compared to sham-operated controls, habenular destruction significantly reduced autoradiographic /sup 3/H-nicotine labeling in rostral (-25%), intermediate (-13%), and lateral subnuclei (-36%). Labeling in the central subnucleus was unchanged. Loss of labeling was maximal at the shortest survival time (3 days) and did not change thereafter. In order to establish whether this loss was due to a reduction in the number or the affinity of /sup 3/H-nicotine-binding sites, a membrane assay was performed on microdissected IPN tissue from rats that had received surgery 3 days previously. Bilateral habenular lesions produced a 35% reduction of high-affinity /sup 3/H-nicotine-binding sites, with no change in binding affinity. Bilateral habenular lesions reduced /sup 125/I-BTX labeling in the intermediate subnuclei, and a slight increase occurred in the rostral subnucleus. In the lateral subnuclei, /sup 125/I-BTX labeling was significantly reduced (27%) at 3 days but not at later survival times. In view of the known synaptic morphology of the habenulointerpeduncular tract, it is concluded that a subpopulation of /sup 3/H-nicotine binding sites within the IPN is located on afferent axons and/or terminals. This subpopulation, located within rostral, intermediate, and lateral subnuclei, may correspond to presynaptic nicotinic cholinergic receptors. Sites that bind /sup 125/I-BTX may include a presynaptic subpopulation located in the lateral and possibly the intermediate subnuclei.

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

    SciTech Connect

    Roeloffzen, Ellen M.A.; Lips, Irene M.; Gellekom, Marion P.R. van; Roermund, Joep van; Frank, Steven J.; Battermann, Jan J.; Vulpen, Marco van

    2010-03-15

    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 {sup 125}I prostate brachytherapy. Methods and Materials: A total of 127 patients treated with {sup 125}I 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 {sup 125}I 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 <.01), most changes were not clinically relevant. A statistically significant improvement at 6 years was seen for mental health, emotional functioning, and insomnia (p <.01). The only clinically relevant changes were seen for emotional functioning and sexual activity. Conclusion: This is the first study presenting prospective HRQOL data up to 6 years after {sup 125}I prostate brachytherapy. HRQOL scores returned to approximately baseline values at 1 year and remained stable up to 6 years after treatment. {sup 125}I prostate brachytherapy did not adversely affect patients' long-term HRQOL.

  3. Aortic lipid and /sup 125/I-albumin accumulation in streptozotocin-diabetic guinea pigs: prevention by insulin treatment

    SciTech Connect

    Schlosser, M.J.; Bannon, A.W.; Verlangieri, A.J.

    1986-03-01

    Diabetes mellitus, a major risk factor of atherosclerosis, is associated with the aortic accumulation of macromolecules. The authors have examined this relationship in the streptozotocin (STZ)-diabetic guinea pig, a species (like man) unable to synthesize ascorbic acid and susceptible to atherosclerosis. Male Dunkin-Hartley guinea pigs received STZ (150 mg/kg, i.c.) or vehicle (control). After 5 days, insulin (10 U/kg/day) was given to half the STZ animals (STZ-INS0 while the remaining half (STZ-SAL) and controls received saline. 25 days later, animals were given /sup 125/I-albumin (100 ..mu..Ci/kg, i.a.). Activity was determined in plasma at 5 (C/sub p5), 15 and 30 minutes, and in the upper thoracic aorta after 30 minutes. Histopathological changes were evaluated in the lower aorta. Aortic albumin permeability defined as cpm/cm/sup 2//sec, cpm/cm/sup 2//sec/C/sub p5/, or cpm/C/sub p5//g tissue was significantly elevated in the STZ-SAL group compared to both STZ-INS and control groups; these latter two groups were not significantly different from each other. Oil-Red-O positive material (lipid) occurred at multifocal areas within the intima of the STZ-SAL animals only. This study demonstrates (1) an abnormal increase in aortic permeability to albumin, (2) histological evidence of early atherosclerotic lesions, and (3) that insulin treatment can prevent these angiopathies in this STZ-diabetic animal model.

  4. Feasibility and impact of the measurement of extracellular fluid volume simultaneous with GFR by 125I-iothalamate.

    PubMed

    Visser, Folkert W; Muntinga, Jaap H J; Dierckx, Rudi A; Navis, Gerjan

    2008-09-01

    The feasibility, validity, and possible applications of the assessment of extracellular fluid volume (ECFV) simultaneous with glomerular filtration rate (GFR) were assessed in a series of validation studies using the constant infusion method of (125)I-iothalamate (IOT). In 48 subjects with a broad range of GFR, distribution volume (V(d)) of IOT corresponded well with V(d) bromide (16.71 +/- 3.0 and 16.73 +/- 3.2 l, respectively, not significant), with a strong correlation (r = 0.933, P < 0.01) and without systematic deviations. Reproducibility assessment in 25 healthy male subjects showed coefficients of variation of 8.6% of duplicate measurement of V(d) IOT during strictly standardized (50 mmol Na(+)/d) sodium intake. An increase in dietary sodium intake (200 mmol Na(+)/d) induced a corresponding rise in V(d) IOT of 1.11 +/- 1.5 l (P < 0.01). In 158 healthy prospective kidney donors, the impact of indexing of GFR to ECFV was analyzed. Age, gender, height, and body surface area (BSA) were determinants of GFR. Whereas GFR, GFR/BSA, and GFR/height were gender-dependent, GFR/ECFV was gender-independent and not related to height or BSA. This supports the potential of normalizing GFR by ECFV. Thus, ECFV can be simultaneously assessed with GFR by the constant infusion method using IOT. After appropriate validation, also other GFR tracers could be used for such a simultaneous estimation, providing a valuable resource of data on ECFV in renal studies and, moreover, allowing GFR to be indexed to the body fluid compartment it clears: the ECFV.

  5. Reagents for astatination of biomolecules. 5. Evaluation of hydrazone linkers in (211)At- and (125)I-labeled closo-decaborate(2-) conjugates of Fab' as a means of decreasing kidney retention.

    PubMed

    Wilbur, D Scott; Chyan, Ming-Kuan; Hamlin, Donald K; Nguyen, Holly; Vessella, Robert L

    2011-06-15

    Evaluation of monoclonal antibody (mAb) fragments (e.g., Fab', Fab, or engineered fragments) as cancer-targeting reagents for therapy with the α-particle emitting radionuclide astatine-211 ((211)At) has been hampered by low in vivo stability of the label and a propensity of these proteins localize to kidneys. Fortunately, our group has shown that the low stability of the (211)At label, generally a meta- or para-[(211)At]astatobenzoyl conjugate, on mAb Fab' fragments can be dramatically improved by the use of closo-decaborate(2-) conjugates. However, the higher stability of radiolabeled mAb Fab' conjugates appears to result in retention of radioactivity in the kidneys. This investigation was conducted to evaluate whether the retention of radioactivity in kidney might be decreased by the use of an acid-cleavable hydrazone between the Fab' and the radiolabeled closo-decaborate(2-) moiety. Five conjugation reagents containing sulfhydryl-reactive maleimide groups, a hydrazone functionality, and a closo-decaborate(2-) moiety were prepared. In four of the five conjugation reagents, a discrete poly(ethylene glycol) (PEG) linker was used, and one substituent adjacent to the hydrazone was varied (phenyl, benzoate, anisole, or methyl) to provide varying acid sensitivity. In the initial studies, the five maleimido-closo-decaborate(2-) conjugation reagents were radioiodinated ((125)I or (131)I), then conjugated with an anti-PSMA Fab' (107-1A4 Fab'). Biodistributions of the five radioiodinated Fab' conjugates were obtained in nude mice at 1, 4, and 24 h post injection (pi). In contrast to closo-decaborate(2-) conjugated to 107-1A4 Fab' through a noncleavable linker, two conjugates containing either a benzoate or a methyl substituent on the hydrazone functionality displayed clearance rates from kidney, liver, and spleen that were similar to those obtained with directly radioiodinated Fab' (i.e., no conjugate). The maleimido-closo-decaborate(2-) conjugation reagent containing a

  6. Reagents for astatination of biomolecules. 5. Evaluation of hydrazone linkers in (211)At- and (125)I-labeled closo-decaborate(2-) conjugates of Fab' as a means of decreasing kidney retention.

    PubMed

    Wilbur, D Scott; Chyan, Ming-Kuan; Hamlin, Donald K; Nguyen, Holly; Vessella, Robert L

    2011-06-15

    Evaluation of monoclonal antibody (mAb) fragments (e.g., Fab', Fab, or engineered fragments) as cancer-targeting reagents for therapy with the α-particle emitting radionuclide astatine-211 ((211)At) has been hampered by low in vivo stability of the label and a propensity of these proteins localize to kidneys. Fortunately, our group has shown that the low stability of the (211)At label, generally a meta- or para-[(211)At]astatobenzoyl conjugate, on mAb Fab' fragments can be dramatically improved by the use of closo-decaborate(2-) conjugates. However, the higher stability of radiolabeled mAb Fab' conjugates appears to result in retention of radioactivity in the kidneys. This investigation was conducted to evaluate whether the retention of radioactivity in kidney might be decreased by the use of an acid-cleavable hydrazone between the Fab' and the radiolabeled closo-decaborate(2-) moiety. Five conjugation reagents containing sulfhydryl-reactive maleimide groups, a hydrazone functionality, and a closo-decaborate(2-) moiety were prepared. In four of the five conjugation reagents, a discrete poly(ethylene glycol) (PEG) linker was used, and one substituent adjacent to the hydrazone was varied (phenyl, benzoate, anisole, or methyl) to provide varying acid sensitivity. In the initial studies, the five maleimido-closo-decaborate(2-) conjugation reagents were radioiodinated ((125)I or (131)I), then conjugated with an anti-PSMA Fab' (107-1A4 Fab'). Biodistributions of the five radioiodinated Fab' conjugates were obtained in nude mice at 1, 4, and 24 h post injection (pi). In contrast to closo-decaborate(2-) conjugated to 107-1A4 Fab' through a noncleavable linker, two conjugates containing either a benzoate or a methyl substituent on the hydrazone functionality displayed clearance rates from kidney, liver, and spleen that were similar to those obtained with directly radioiodinated Fab' (i.e., no conjugate). The maleimido-closo-decaborate(2-) conjugation reagent containing a

  7. Reagents for Astatination of Biomolecules. 5. Evaluation of hydrazone linkers in 211At- and 125I-labeled closo-decaborate(2-) conjugates of Fab′ as a means of decreasing kidney retention

    PubMed Central

    Wilbur, D. Scott; Chyan, Ming-Kuan; Hamlin, Donald K.; Nguyen, Holly; Vessella, Robert L.

    2011-01-01

    Evaluation of monoclonal antibody (MAb) fragments (e.g. Fab′, Fab or engineered fragments) as cancer-targeting reagents for therapy with the α-particle emitting radionuclide astatine-211 (211At) has been hampered by low in vivo stability of the label and a propensity of these proteins localize to kidneys. Fortunately, our group has shown that the low stability of the 211At label, generally a meta- or para-[211At]astatobenzoyl conjugate, on MAb Fab′ fragments can be dramatically improved by use of closo-decaborate(2-) conjugates. However, the higher stability of radiolabeled MAb Fab′ conjugates appears to result in retention of the radioactivity in kidneys. This investigation was conducted to evaluate whether the retention of radioactivity in kidney might be decreased by the use of acid-cleavable hydrazone between the Fab′ and the radiolabeled closo-decaborate(2-) moiety. Five conjugation reagents containing sulfhydryl-reactive maleimide groups, a hydrazone functionality and a closo-decaborate(2-) moiety were prepared. In four of the five conjugation reagents, a discrete polyethylene glycol (PEG) linker was used, and one substituent adjacent to the hydrazone was varied (phenyl, benzoate, anisole or methyl) to provide varying acid-sensitivity. In the initial studies, the five maleimido-closo-decaborate(2-) conjugation reagents were radioiodinated (125I or 131I), then conjugated with an anti-PSMA Fab′ (107-1A4 Fab′). Biodistributions of the five radioiodinated Fab′ conjugates were obtained in nude mice at 1, 4 and 24 h post injection (pi). In contrast to closo-decaborate(2-) conjugated to 107-1A4 Fab′ through a non-cleavable linker, two conjugates containing either a benzoate or a methyl substituent on the hydrazone functionality displayed clearance rates from kidney, liver and spleen that were similar to those obtained with directly radioiodinated Fab′ (i.e. no conjugate). The maleimido-closo-decaborate(2-) conjugation reagent containing a benzoate

  8. Leaving home ain't easy: non-local seed dispersal is only evolutionarily stable in highly unpredictable environments.

    PubMed

    Snyder, Robin E

    2011-03-01

    It is widely understood that in the presence of asynchronous environmental variation, seeds disperse to escape disturbances, avoid crowding or colonize newly favourable habitat before a superior competitor can arrive. If seeds are dispersing for any of these reasons, it seems intuitive that they should travel far enough to reach conditions uncorrelated with their natal environment: why 'escape in space' only to land somewhere more or less like where they started? However, in this paper, I present a series of mathematical experiments which show that the evolutionarily stable mean dispersal distance remains well short of the spatial correlation length of the environmental variation, regardless of disturbance severity, coevolution with a superior competitor or the presence of a small fraction of seeds which travel well beyond the mean distance. Non-local dispersal arises only as part of a polymorphism that evolves when favourable conditions are fleeting. To the degree that non-local dispersal is a response to environmental variation, it appears to be a response to environmental unpredictability.

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

    SciTech Connect

    Sahgal, Arjun; Jabbari, Siavash; Chen, Josephine; Pickett, Barbie; Roach, Mack; Weinberg, Vivian; Hsu, I-C.; Pouliot, Jean

    2008-09-01

    Purpose: To compare the urethral and prostate absolute and biologic effective doses (BEDs) for {sup 131}Cs and {sup 125}I prostate permanent implant brachytherapy (PPI). Methods and Materials: Eight previously implanted manually planned {sup 125}I PPI patients were replanned manually with {sup 131}Cs, and re-planned using Inverse Planning Simulated Annealing. {sup 131}Cs 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 {alpha}/{beta} ratio of 2 and was also calculated for the prostate using an {alpha}/{beta} ratio of 6 and a urethral {alpha}/{beta} ratio of 2. The primary endpoints of this study were the prostate D{sub 90} BED (pD{sub 90}BED) and urethral D{sub 30} BED normalized to the maximal potential prostate D{sub 90} BED (nuD{sub 30}BED). Results: The manual plan comparison ({alpha}/{beta} = 2) yielded no significant difference in the prostate D{sub 90} BED (median, 192 Gy{sub 2} for both isotopes). No significant difference was observed for the nuD{sub 30}BED (median, 199 Gy{sub 2} and 202 Gy{sub 2} for {sup 125}I and {sup 131}Cs, respectively). For the inverse planning simulated annealing plan comparisons ({alpha}/{beta} 2), the prostate D{sub 90} BED was significantly lower with {sup 131}Cs than with {sup 125}I (median, 177 Gy{sub 2} vs. 187 Gy{sub 2}, respectively; p = 0.01). However, the nuD{sub 30}BED was significantly greater with {sup 131}Cs than with {sup 125}I (median, 192 Gy{sub 2} vs. 189 Gy{sub 2}, respectively; p = 0.01). Both the manual and the inverse planning simulated annealing plans resulted in a significantly lower prostate D{sub 90} BED (p = 0.01) and significantly greater nuD{sub 30}BED for {sup 131}Cs (p = 0.01), compared with {sup 125}I, when the prostate {alpha}/{beta} ratio was 6 and the urethral {alpha}/{beta} ratio was 2. Conclusion: This report highlights the controversy in comparing the dose to both the prostate and the organs

  10. Influence of ionic strength, EDTA concentration, endogenous C1q and polyanions on the 125I-C1q-binding test.

    PubMed

    Hack, C E; Huijbregts, C C; Paardekooper, J

    1984-08-01

    Several parameters of the 125I-C1q-binding test were investigated: ionic strength, pH, concentration of EDTA, influence of serum C1q and the possibility of interference by polyanions. Lowering the ionic strength of the borate buffer resulted in increased precipitation of 125I-C1q in normal human serum. This increase was dependent on the presence of serum proteins, probably immunoglobulins. When the concentration of the EDTA was decreased, increased precipitation of 125I-C1q in normal human serum was also observed. This was prevented by adding NaCl to the EDTA solution. However at very low concentrations of EDTA (too low to chelate all calcium ions in the serum), increased precipitation of 125I-C1q in normal human serum was observed even in the presence of added NaCl. Addition of purified C1q to sera from patients with very low C1q levels had varying effects on the results of the C1q-binding test: (a) it decreased the C1q-binding activity of some sera, probably by competition with 125I-C1q for binding sites on the immune complexes; (b) it increased the C1q-binding activity of other sera, probably by enhancing the precipitation of immune complexes as a consequence of the cross-linking effect of C1q; or (c) it had no influence, possibly due to the opposite effects of (a) and (b). The addition of dextran sulphate resulted in a dose-dependent increase in the 125I-C1q-binding activity of normal human serum. This effect was dependent on the interaction of dextran sulphate with either C1q or low-density lipoproteins and was prevented by addition of polybrene to the assay. However, addition of polybrene to sera with a high C1q-binding activity scarcely influenced binding activity.

  11. Enhancement of local species richness in tundra by seed dispersal through guts of muskox and barnacle goose.

    PubMed

    Bruun, Hans Henrik; Lundgren, Rebekka; Philipp, Marianne

    2008-02-01

    The potential contribution of vertebrate-mediated seed rain to the maintenance of plant community richness in a High Arctic ecosystem was investigated. We analyzed viable seed content in dung of the four numerically most important terrestrial vertebrates in Northeast Greenland - muskox (Ovibos moschatus), barnacle goose (Branta leucopsis), Arctic fox (Alopex lagopus) and Arctic hare (Lepus arcticus). High numbers of plant propagules were found in the dung of muskox and barnacle goose. Seeds of many plant species were found in the faeces of one vertebrate species only. Propagule composition in barnacle goose droppings was relatively uniform over samples, with a high abundance of the nutritious bulbils of Polygonum viviparum (Bistorta vivipara), suggesting that geese have a narrow habitat preference and feed selectively. Propagule composition in muskox dung was diverse and heterogeneous among samples, suggesting a generalist approach in terms of food selection and the haphazard ingestion of plant propagules with foliage. The species composition of plant propagules in dung samples was different from that of the receiving plant communities (in terms of the Sørensen and Czekanowski dissimilarity indices), and dung deposition, especially by muskox, often brought new species to the receiving community. The results suggest that endozoochorous propagule dispersal in the Arctic has a great potential in the generation and maintenance of local species richness, albeit being little specialized. It is further suggested that endozoochory is an important means of long-distance dispersal and, thereby, of plant migration in response to climate change.

  12. Enhancement of local species richness in tundra by seed dispersal through guts of muskox and barnacle goose.

    PubMed

    Bruun, Hans Henrik; Lundgren, Rebekka; Philipp, Marianne

    2008-02-01

    The potential contribution of vertebrate-mediated seed rain to the maintenance of plant community richness in a High Arctic ecosystem was investigated. We analyzed viable seed content in dung of the four numerically most important terrestrial vertebrates in Northeast Greenland - muskox (Ovibos moschatus), barnacle goose (Branta leucopsis), Arctic fox (Alopex lagopus) and Arctic hare (Lepus arcticus). High numbers of plant propagules were found in the dung of muskox and barnacle goose. Seeds of many plant species were found in the faeces of one vertebrate species only. Propagule composition in barnacle goose droppings was relatively uniform over samples, with a high abundance of the nutritious bulbils of Polygonum viviparum (Bistorta vivipara), suggesting that geese have a narrow habitat preference and feed selectively. Propagule composition in muskox dung was diverse and heterogeneous among samples, suggesting a generalist approach in terms of food selection and the haphazard ingestion of plant propagules with foliage. The species composition of plant propagules in dung samples was different from that of the receiving plant communities (in terms of the Sørensen and Czekanowski dissimilarity indices), and dung deposition, especially by muskox, often brought new species to the receiving community. The results suggest that endozoochorous propagule dispersal in the Arctic has a great potential in the generation and maintenance of local species richness, albeit being little specialized. It is further suggested that endozoochory is an important means of long-distance dispersal and, thereby, of plant migration in response to climate change. PMID:17990003

  13. Population differences in host use by a seed-beetle: local adaptation, phenotypic plasticity and maternal effects.

    PubMed

    Amarillo-Suárez, Angela R; Fox, Charles W

    2006-11-01

    For insects that develop inside discrete hosts, both host size and host quality constrain offspring growth, influencing the evolution of body size and life history traits. Using a two-generation common garden experiment, we quantified the contribution of maternal and rearing hosts to differences in growth and life history traits between populations of the seed-feeding beetle Stator limbatus that use a large-seeded host, Acacia greggii, and a small-seeded host, Pseudosamanea guachapele. Populations differed genetically for all traits when beetles were raised in a common garden. Contrary to expectations from the local adaptation hypothesis, beetles from all populations were larger, developed faster and had higher survivorship when reared on seeds of A. greggii (the larger host), irrespective of their native host. We observed two host plant-mediated maternal effects: offspring matured sooner, regardless of their rearing host, when their mothers were reared on P. guachapele (this was not caused by an effect of rearing host on egg size), and females laid larger eggs on P. guachapele. This is the first study to document plasticity by S. limbatus in response to P. guachapele, suggesting that plasticity is an ancestral trait in S. limbatus that likely plays an important role in diet expansion. Although differences between populations in growth and life history traits are likely adaptations to their host plants, host-associated maternal effects, partly mediated by maternal egg size plasticity, influence growth and life history traits and likely play an important role in the evolution of the breadth of S. limbatus' diet. More generally, phenotypic plasticity mediates the fitness consequences of using novel hosts, likely facilitating colonization of new hosts, but also buffering herbivores from selection post-colonization. Plasticity in response to novel versus normal hosts varied among our study populations such that disentangling the historical role of plasticity in

  14. Biochemical and ultrastructural processing of (/sup 125/I)epidermal growth factor in rat epidermis and hair follicles: accumulation of nuclear label

    SciTech Connect

    Green, M.R.; Mycock, C.; Smith, C.G.; Couchman, J.R.

    1987-03-01

    Although the intracellular ultrastructural processing of epidermal growth factor (EGF) and its receptor have been described in cell culture systems, very few studies have examined this phenomenon in intact tissues. We have examined the ultrastructural and biochemical handling of (/sup 125/I)EGF in the epidermis and hair follicle bulb of intact, viable, 3- to 5-day-old rat skin the EGF receptor distribution of which has already been documented and in which EGF has been shown to be biologically active. After incubation of explants with 10 nM (/sup 125/I)EGF for 2.5 h at 25 degrees or 37 degrees C, radiolabel was detected over the basal cells of the epidermis and hair follicle outer root sheath, confirming previous light microscope observations. More specifically, silver grains were observed near coated and uncoated plasma membrane and coated membrane invaginations, Golgi apparatus, lysosomal structures, and nuclei. Sodium azide inhibited internalization of label, whereas a series of lysosomal inhibitors (chloroquine, monensin, and iodoacetamide) caused a slight increase in silver grains associated with lysosomal vesicles and a decrease in nuclear label. Biochemical analysis indicated that greater than 35% of radioactivity following incubation at 37 degrees C was in the form of degraded (/sup 125/I)EGF fragments and that inclusion of chloroquine, monensin, and iodoacetamide reduced this value to 20.8%, 8.6%, and 4.0%, respectively. In addition, chloramine T-prepared (/sup 125/I)EGF was found to be covalently cross-linked with low efficiency to a protein having the molecular weight of the EGF receptor. These data are discussed in the light of the effects of EGF on epithelial cell proliferation in skin.

  15. Comparison of whole body and tissue blood volumes in rainbow trout (Salmo gairdneri) with 125I bovine serum albumin and 51Cr-erythrocyte tracers

    USGS Publications Warehouse

    Gingerich, W.H.; Pityer, R.A.

    1989-01-01

    Total, packed cell and, plasma volume estimates were made for the whole body and selected tissues of rainbow trout by the simultaneous injection of radiolabelled trout erythrocyte (51Cr-RBC) and radioiodinated bovine serum albumin (125I-BSA) tracers. Blood volumes were estimated with both markers separately by the tracer-hematocrit method and as the combination of the 51Cr-RBC packed cell and 125I-BSA plasma volumes. Mean whole body blood volume was significantly less when calculated from the 51Cr-RBC tracer data (3.52±0.78 ml/100 g; ±SD) than when calculated with the 125I-BSA tracer (5.06±0.86 ml/100 g) or as the sum of the two volumes combined (4.49±0.60 ml/100 g). The whole body hematocrit (28±5%), estimated as the quotient of the 51Cr-RBC volume divided by the sum of the 125I-BSA and the 51Cr-RBC volumes, also was significantly less than the dorsal aortic microhematocrit (36±4%). Estimates of total blood volumes in most tissues were significantly smaller when calculated from the51Cr-RBC data than when calculated by the other two methods. Tissue blood volumes were greatest in highly vascularized and well perfused tissues and least in poorly vascularized tissues. The relative degree of vascularization among tissues generally remained the same regardless of whether the red cell or the plasma tracer was used to calculated blood volume. It is not clear whether the expanded plasma volume is the result of the distribution of erythrocyte-poor blood into the secondary circulation or the result of extravascular exchange of plasma proteins.

  16. Affinity crosslinking of /sup 125/I-human beta-endorphin to cell lines possessing either mu or delta type opioid binding sites

    SciTech Connect

    Keren, O.; Gioannini, T.L.; Hiller, J.M.; Simon, E.J.

    1986-01-01

    Affinity crosslinking of human /sup 125/I-beta-Endorphin to cell lines possessing either mu or delta binding sites was carried out. Autoradiography of SDS-PAGE gels from these crosslinked cell lines revealed that these two sites contain major peptide subunits that differ in molecular size. This confirms our earlier finding in mammalian brain which demonstrated separate and distinct subunits for mu and delta opioid receptors.

  17. Effects of oral contraceptives, or lanosterol, on ADP-induced aggregation and binding of /sup 125/I-fibrinogen to rat platelets

    SciTech Connect

    McGregor, L.; Toor, B.; McGregor, J.L.; Renaud, S.; Clemetson, K.J.

    1984-03-01

    The aggregation to ADP and the binding of /sup 125/I-fibrinogen to platelets from rats treated with oral contraceptives or normal platelets treated in vitro with lanosterol were compared to their respective controls. Both types of platelets showed a significant increase in ADP-induced aggregation and in binding of fibrinogen, indicating that the effect of oral contraceptives could be partly due to increased levels of lanosterol in platelet membrane.

  18. Multiple conformations of 5-HT2A and 5-HT 2C receptors in rat brain: an autoradiographic study with [125I](±)DOI.

    PubMed

    López-Giménez, Juan F; Vilaró, M Teresa; Palacios, José M; Mengod, Guadalupe

    2013-10-01

    Earlier autoradiographic studies with the 5-HT2 receptor agonist [(125)I](±)DOI in human brain showed unexpected biphasic competition curves for various 5-HT2A antagonists. We have performed similar studies in rat brain regions with selective 5-HT2A (M100907) and 5-HT2C (SB242084) antagonists together with ketanserin and mesulergine. The effect of GTP analogues on antagonist competition was also studied. Increasing concentrations of Gpp(NH)p or GTPγS resulted in a maximal inhibition of [(125)I](±)DOI-specific binding of approximately 50 %. M100907 competed biphasically in all regions. In the presence of 100 μM Gpp(NH)p, M100907 still displaced biphasically the remaining [(125)I](±)DOI binding. Ketanserin showed biphasic curves in some regions and monophasic curves in others. In the latter, Gpp(NH)p evidenced an additional high-affinity site. SB242084 competed biphasically in brainstem nuclei and monophasically in the other regions. In most areas, SB242084 affinities were not notably altered by Gpp(NH)p. Mesulergine competed monophasically in all regions without alteration by Gpp(NH)p. These results conform with the extended ternary complex model of receptor action: receptor exists as an equilibrium of multiple conformations, i.e. ground (R), partly activated (R*) and activated G-protein-coupled (R*G) conformation/s. Thus, [(125)I](±)DOI would label multiple conformations of both 5-HT2A and 5-HT2C receptors in rat brain, and M100907 and ketanserin would recognise these conformations with different affinities.

  19. Relationship of changing delta 4-steroid 5 alpha-reductase activity to (125I)iododeoxyuridine uptake during regeneration of involuted rat prostates

    SciTech Connect

    Kitahara, S.; Higashi, Y.; Takeuchi, S.; Oshima, H. )

    1989-04-01

    To elucidate the phenotypic expression of proliferating prostatic cells, rats were castrated, and the regenerating process of involuted ventral prostates during testosterone propionate (TP) administration was investigated by examining morphology, (5-{sup 125}I)iododeoxyuridine ({sup 125}I-UdR) uptake, DNA content, weight, acid phosphatase, and delta 4-steroid 5 alpha-reductase (5 alpha-reductase) activities. Morphologically, TP treatment initially increased the number of epithelial cells lining glandular lobules and subsequently restored the shape of epithelial cells. {sup 125}I-UdR uptake peaked on Day 3 of TP treatment and stayed at higher levels than for uncastrated controls until Day 14 of treatment. Prostatic weight, protein content, acid phosphatase, and DNA content returned to uncastrated control levels by Day 14 of TP treatment. TP administration markedly stimulated prostatic 5 alpha-reductase activity, which peaked on the Day 5 of treatment and decreased to uncastrated control levels by Day 14 of treatment. It is concluded that TP administration to castrated rats initially induced active mitotic division of the remaining stem cells, followed by formation of differentiated functional epithelial cells. Prostatic 5 alpha-reductase was highly active at the initial phase of active mitotic cell division. The major portion of the increased enzyme activity can be regarded as a phenotypic expression of stem or transient cells of prostatic epithelium.

  20. 125I-DPDYN, monoiodo(D-Pro10)dynorphin(1-11): a highly radioactive and selective probe for the study of kappa opioid receptors

    SciTech Connect

    Gairin, J.E.; Jomary, C.; Pradayrol, L.; Cros, J.; Meunier, J.C.

    1986-02-13

    The mono- and diiodinated derivatives of the kappa-selective ligand (D-Pro10)dynorphin(1-11), DPDYN, were prepared. Their binding properties at the three opioid receptor types (mu, delta and kappa) were examined and compared to those of the parent peptide. The monoiodo derivative shows a general although moderate decrease in affinity and retains high kappa selectivity (KI mu/KI kappa = 48 and KI delta/KI kappa = 140). The binding properties of the diiodo derivative are found to be dramatically decreased. Radioiodination of DPDYN leads to the monoiodinated peptide with high specific activity (700-800 Ci/mmol). In guinea-pig cerebellum membranes, a kappa-specific tissue, (125I)-labelled monoiodo(D-Pro10)dynorphin(1-11), 125I-DPDYN, interacts specifically and reversibly with a single class of binding sites (Bmax = 118 fmol/mg protein) with a high affinity (KD = 0.12 nM from equilibrium experiments, 0.18 nM from kinetics studies). Therefore, because of its high specific radioactivity, high affinity and reasonably good selectivity, 125I-DPDYN designates itself as the probe of the k-opioid receptor type.

  1. /sup 125/I-luteinizing hormone (LH) binding to soluble receptors from the primate (Macaca mulatta) corpus luteum: effects of ethanol exposure

    SciTech Connect

    Danforth, D.R.; Stouffer, R.L.

    1988-01-01

    In the current study, we compared the effects of ethanol on gonadotropin receptors solubilized from macaque luteal membranes to those on receptors associated with the lipid bilayer. Treatment with 1% Triton X-100 for 30 min at 4C, followed by precipitation with polyethylene glycol, resulted in recovery of 50% more binding sites for /sup 125/I-human luteinizing hormone (hLH) than were available in particulate preparations. However, the soluble receptors displayed a 3-fold lower affinity for /sup 125/I-hLH. Conditions which enhanced LH binding to particulates, i.e., 1-8% ethanol at 25C, decreased specific /sup 125/I-hLH binding to soluble receptors. Steady-state LH binding to soluble receptors during incubation at 4C was half of that observed at 25C. The presence of 8% ethanol at 4C restored LH binding to levels observed in the absence of ethanol at 25C. Thus, LH binding sites in the primate corpus luteum can be effectively solubilized with Triton X-100. The different binding characteristics of particulate and soluble receptors, including the response to ethanol exposure, suggest that the lipid environment in the luteal membrane modulates the availability and affinity of gonadotropin receptors.

  2. Uptake and therapeutic effectiveness of /sup 125/I- and /sup 211/At-methylene blue for pigmented melanoma in an animal model system

    SciTech Connect

    Link, E.M.; Brown, I.; Carpenter, R.N.; Mitchell, J.S.

    1989-08-01

    The investigations concerning a targeted radiotherapy for pigmented melanoma with a radiolabeled phenothiazine derivative, 3,7-(dimethylamino)phenazathionium chloride (methylene blue (MTB)), were continued using melanotic and amelanotic sublines of B16 melanoma. Two radionuclides, 125I and 211At, emitting Auger electrons and alpha particles, respectively, replaced 35S previously studied since their biological effectiveness is significantly higher. In vitro autoradiography revealed a selective accumulation of methylene blue labeled with either of the radioisotopes in pigmented melanoma cells but its absence in nonpigmented cells. Treatments with (125I)MTB and (211At)MTB were performed both in vitro and in vivo, with their effectiveness determined by lung clonogenic assay. (125I)MTB proved to be relatively ineffective when incorporated into melanosomes distributed in the cytoplasm, i.e., too far away from the genome. Conspicuous therapeutic effects were achieved with (211At)MTB for pigmented melanoma only. 211At itself did not affect either of the investigated sublines of B16 melanoma confirming once again the high affinity of methylene blue to melanin. Calculations of cumulative radiation doses from (211At)MTB deposited in melanotic melanoma tumors and pigmented normal organs which would be at a particular risk led to the conclusion that (211At)MTB could be used for a highly selective and very efficient targeted radiotherapy of pigmented melanomas without damaging normal tissues.

  3. Simple, rapid /sup 125/I-labeled cyclosporine double antibody/polyethylene glycol radioimmunoassay used in a pediatric cardiac transplant program

    SciTech Connect

    Berk, L.S.; Webb, G.; Imperio, N.C.; Nehlsen-Cannarella, S.L.; Eby, W.C.

    1986-01-01

    We modified the Sandoz cyclosporine radioimmunoassay because of our need for frequent clinical monitoring of cyclosporine drug levels in allo- and xenograft pediatric cardiac transplant patients. With application of a commercially available (/sup 125/I)cyclosporine label in place of (/sup 3/H)cyclosporine and a second antibody/polyethylene glycol (PEG) method of separation in place of charcoal separation, we simplified and enhanced the speed and precision of assay performance. Studies of 140 whole blood samples comparing this new method to the (/sup 3/H)cyclosporine radioimmunoassay (RIA) method of Berk and colleagues yielded a coefficient of correlation of 0.96 (p less than 0.00001) with means of 626 and 667 ng/ml for (/sup 3/H)RIA and (/sup 125/I)RIA, respectively, and a regression equation of y = 28 + 1.02x. The major advantages are that total assay time is reduced to approximately 1 h; (/sup 125/I)cyclosporine label is used, avoiding the problems associated with liquid scintillation counting; and precision is enhanced by separating bound and free fractions with second antibody/PEG. These modifications should provide for greater ease of assay performance and improved clinical utility of cyclosporine monitoring not only in the pediatric but also in the adult transplant patient.

  4. Characterization and modulation of [125I]iberiotoxin-D19Y/Y36F binding in the guinea-pig urinary bladder.

    PubMed

    Molinari, E J; Sullivan, J P; Wan, Y; Brioni, J D; Gopalakrishnan, M

    2000-01-28

    The radioligand binding characteristics of the Ca(2+)-activated K(+) channel ligand [125I]iberiotoxin-D19Y/Y36F were examined in guinea-pig urinary bladder membranes. Saturation analysis revealed a single class of high affinity binding sites in the bladder with a K(D) value of 45.6 pM and a B(max) value of 112 fmol/mg protein. Specific binding was displaced by unlabeled iberiotoxin and penitrem A, but not by blockers of other classes of K(+) channels including alpha-dendrotoxin, margatoxin and apamin. The indole alkaloids, paxilline and verruculogen, significantly increased binding by 4.5- and 4.3-fold, respectively. Tetraacetic acid derivatives such as ethylenediamine tetraacetic acid and ethyleneglycoltetraacetic acid enhanced specific [125I]iberiotoxin-D19Y/Y36F binding about 2.5-fold, which was not attributable to calcium chelation. This increase was due to a significant change in ligand binding affinity (K(D)=6.3 pM), but not due to a change in the B(max), indicating that these compounds may enhance toxin binding via allosteric interactions. Collectively, these results demonstrate that the binding sites for [125I]iberiotoxin-D19Y/Y36F present in the urinary bladder shows a pharmacological profile typical of maxi-K(+) channels and can be modulated, not only by previously known indole alkaloids, but also by tetraacetic acid analogs. PMID:10666507

  5. The standardization methods of radioactive sources (125I, 131I, 99mTc, and 18F) for calibrating nuclear medicine equipment in Indonesia

    NASA Astrophysics Data System (ADS)

    Wurdiyanto, G.; Candra, H.

    2016-03-01

    The standardization of radioactive sources (125I, 131I, 99mTc and 18F) to calibrate the nuclear medicine equipment had been carried out in PTKMR-BATAN. This is necessary because the radioactive sources used in the field of nuclear medicine has a very short half-life in other that to obtain a quality measurement results require special treatment. Besides that, the use of nuclear medicine techniques in Indonesia develop rapidly. All the radioactive sources were prepared by gravimetric methods. Standardization of 125I has been carried out by photon- photon coincidence methods, while the others have been carried out by gamma spectrometry methods. The standar sources are used to calibrate a Capintec CRC-7BT radionuclide calibrator. The results shows that calibration factor for Capintec CRC-7BT dose calibrator is 1,03; 1,02; 1,06; and 1,04 for 125I, 131I, 99mTc and 18F respectively, by about 5 to 6% of the expanded uncertainties.

  6. Effects of atropine treatment on in vitro and in vivo binding of 4-[125I]-dexetimide to central and myocardial muscarinic receptors.

    PubMed

    Uno, Y; Matsumura, K; Scheffel, U; Wilson, A A; Dannals, R F; Wagner, H N

    1991-01-01

    Upregulation of muscarinic cholinergic receptors (mAChR) after chronic atropine treatment has been described previously. The present study was designed to evaluate 4-iodine-125 dexetimide as an agent to determine changes in the number of mAChR. Rats were injected subcutaneously with atropine (500 mg/kg) either once or chronically, once daily for 10 days, and sacrificed 24 h later. In vitro binding assays with 4-[125I]-dexetimide showed significant increases in the number of mAChR in cerebra (21%) and ventricles (45%) after chronic atropine treatment but not after acute treatment. The affinity of binding to cerebral and ventricular mAChR declined after acute and chronic atropine treatment. In vivo studies were carried out involving intravenous injection of 4-[125I]-dexetimide 24 h after atropine treatment. Binding was markedly reduced in the brain and heart. Upregulation of mAChR, as seen in in vitro studies, could not be observed because of the remaining atropine. Occupancy of mAChR by atropine persisted as long as 7 days after one dose. The results of these studies indicate that 4-[125I]-dexetimide binding reflects the effects of atropine on central and peripheral muscarinic cholinergic receptors in vitro and in vivo. PMID:1915471

  7. The self-defining critical group and its application to a measured check of the derived limit for [sup 125]I in drinking water

    SciTech Connect

    Bowlt, C.; Howe, J.R. )

    1992-12-01

    Using a series of daily measurements of [sup 125]I in the drinking water of North Surrey, England, from November 1988 through May 1990, the accumulated activities in the thyroids of adults drinking such water were calculated on the assumption that the fraction of ingested iodine taken up by the thyroid was f = 0.3 and the tap water consumption was C = 600 L y[sup [minus]1]. These figures were compared with measured values of [sup 125]I activities in 42 thyroids taken at necropsy from residents in the North Surrey area who were dying during this same time period. Eight thyroids (19%) had measured activities greater than predicted, so they were named the self-defining critical group. After comparing the thyroid with the drinking water activity, the current generalized derived limit for [sup 125]I in the drinking water may be too high by a factor of 2. The reason for this appears to be the use of f = 0.3 which is the mean value for the normal' population. Models involving critical groups should use values of parameters different from the mean. In the present case, making f = 0.6 would remove the discrepancy between measurement and prediction and would be in reasonable accord with measured distributions of f.

  8. The influence of exercise-induced oxidative stress on binding and degradation of 125I-insulin by the receptors on erythrocytes.

    PubMed

    Szcześniak, L; Karolkiewicz, J; Deskur, E; Rychlewski, T; Konys, L; Stankiewicz, K

    1998-09-01

    In the present work we investigated the influence of oxidative stress induced by strenuous exercise on the affinity of a specific insulin receptors on human erythrocytes. 13 male members of the national basketball staff performed a maximal treadmill exercise test. In the blood samples collected before and directly after the test acid-base equilibrium parameters, lactic acid concentrations, glucose and insulin serum levels as well as 125I-insulin binding and degradation by receptor on erythrocytes were measured. As markers of oxidative stress, plasma thiobarbituric acid-reactive substance levels (TBARS) and red blood cells glutathione content (GSH) were determined. After the exercise test TBARS levels increased significantly and GSH concentrations decreased indicating that oxidative stress occurred. Binding of 125I-insulin to the receptors on erythrocytes decreased significantly during the test, while there was only insignificant reduction in 125I-insulin degradation. Correlation analysis and multiple linear regression revealed that changes in insulin degradation by receptors on erythrocytes during exhaustive exercise are determined by oxidative stress, probably via oxidation of sulfhydryl groups of certain enzymes. The affinity of receptors for insulin seems to depend mainly on glucose concentrations.

  9. Autoradiography for iodine-125 seeds

    SciTech Connect

    Alberti, W.; Divoux, S. ); Pothmann, B.; Tabor, P. ); Hermann, K.P.; Harder, D. )

    1993-04-02

    To study the interior design of model 6702 and 6711 iodine-125 seeds, contact autoradiographs were performed using mammography film. Improved resolution was obtained using a pin-hole camera with a hole of 0.1 mm [times] 0.1 mm. With these techniques, qualitative determination of the relative activity distribution within each seed was possible. The number of the activated resin spheres and the positions of the centers of these spheres can be exactly determined. A model calculation shows that variations in the arrangement of the activated spheres within a seed have a moderate influence on the dose distribution at source distances below 10 mm. Knowing the exact source configuration may be useful when comparing dose calculations with measured data for model 6702 [sup 125]I seeds which are currently employed in ophthalmic plaque and implant therapy of other tumors. 16 refs., 5 figs., 2 tabs.

  10. Mammographical mass detection and classification using local seed region growing-spherical wavelet transform (LSRG-SWT) hybrid scheme.

    PubMed

    Görgel, Pelin; Sertbas, Ahmet; Ucan, Osman N

    2013-07-01

    The purpose of this study is to implement accurate methods of detection and classification of benign and malignant breast masses in mammograms. Our new proposed method, which can be used as a diagnostic tool, is denoted Local Seed Region Growing-Spherical Wavelet Transform (LSRG-SWT), and consists of four steps. The first step is homomorphic filtering for enhancement, and the second is detection of the region of interests (ROIs) using a Local Seed Region Growing (LSRG) algorithm, which we developed. The third step incoporates Spherical Wavelet Transform (SWT) and feature extraction. Finally the fourth step is classification, which consists of two sequential components: the 1st classification distinguishes the ROIs as either mass or non-mass and the 2nd classification distinguishes the masses as either benign or malignant using a Support Vector Machine (SVM). The mammograms used in this study were acquired from the hospital of Istanbul University (I.U.) in Turkey and the Mammographic Image Analysis Society (MIAS). The results demonstrate that the proposed scheme LSRG-SWT achieves 96% and 93.59% accuracy in mass/non-mass classification (1st component) and benign/malignant classification (2nd component) respectively when using the I.U. database with k-fold cross validation. The system achieves 94% and 91.67% accuracy in mass/non-mass classification and benign/malignant classification respectively when using the I.U. database as a training set and the MIAS database as a test set with external validation.

  11. Observational Signatures of High-Redshift Quasars and Local Relics of Black Hole Seeds

    NASA Astrophysics Data System (ADS)

    Reines, Amy E.; Comastri, Andrea

    2016-10-01

    Observational constraints on the birth and early evolution of massive black holes come from two extreme regimes. At high redshift, quasars signal the rapid growth of billion-solar-mass black holes and indicate that these objects began remarkably heavy and/or accreted mass at rates above the Eddington limit. At low redshift, the smallest nuclear black holes known are found in dwarf galaxies and provide the most concrete limits on the mass of black hole seeds. Here, we review current observational work in these fields that together are critical for our understanding of the origin of massive black holes in the Universe.

  12. Feasibility of vibro-acoustography with a quasi-2D ultrasound array transducer for detection and localizing of permanent prostate brachytherapy seeds: A pilot ex vivo study

    SciTech Connect

    Mehrmohammadi, Mohammad; Kinnick, Randall R.; Fatemi, Mostafa; Alizad, Azra; Davis, Brian J.

    2014-09-15

    Purpose: Effective permanent prostate brachytherapy (PPB) requires precise placement of radioactive seeds in and around the prostate. The impetus for this research is to examine a new ultrasound-based imaging modality, vibro-acoustography (VA), which may serve to provide a high rate of PPB seed detection while also effecting enhanced prostate imaging. The authors investigate the ability of VA, implemented on a clinical ultrasound (US) scanner and equipped with a quasi-2D (Q2D) array US transducer, to detect and localize PPB seeds in excised prostate specimens. Methods: Nonradioactive brachytherapy seeds were implanted into four excised cadaver prostates. A clinical US scanner equipped with a Q2D array US transducer was customized to acquire both US and C-scan VA images at various depths. The VA images were then used to detect and localize the implanted seeds in prostate tissue. To validate the VA results, computed tomography (CT) images of the same tissue samples were obtained to serve as the reference by which to evaluate the performance of VA in PPB seed detection. Results: The results indicate that VA is capable of accurately identifying the presence and distribution of PPB seeds with a high imaging contrast. Moreover, a large ratio of the PPB seeds implanted into prostate tissue samples could be detected through acquired VA images. Using CT-based seed identification as the standard, VA was capable of detecting 74%–92% of the implanted seeds. Additionally, the angular independency of VA in detecting PPB seeds was demonstrated through a well-controlled phantom experiment. Conclusions: Q2DVA detected a substantial portion of the seeds by using a 2D array US transducer in excised prostate tissue specimens. While VA has inherent advantages associated with conventional US imaging, it has the additional advantage of permitting detection of PPB seeds independent of their orientation. These results suggest the potential of VA as a method for PPB imaging that

  13. The production, localization and spreading of reactive oxygen species contributes to the low vitality of long-term stored common beech (Fagus sylvatica L.) seeds.

    PubMed

    Ratajczak, Ewelina; Małecka, Arleta; Bagniewska-Zadworna, Agnieszka; Kalemba, Ewa Marzena

    2015-02-01

    The common beech (Fagus sylvatica L.) is propagated by seeds, but the seed set is irregular with five to ten years in between crops. It is therefore necessary to store the seeds. However, beech seeds lose germinability during long-term storage. In this study, beech seeds were stored at -10°C under controlled conditions for 2, 5, 8, 11 and 13 years. Our results show that beech seeds lose germinability during storage in proportion to the duration of storage. The decrease in germinability correlated with increased electrolyte leakage and accumulation of superoxide anion radicals, hydrogen peroxide and hydroxyl radicals. Furthermore, a strong positive correlation was observed among the releases of superoxide anion radicals, hydrogen peroxide and hydroxyl radicals. In situ localization showed that superoxide anion radicals and hydrogen peroxide were first detectable in root cap cells. When the seed storage time was extended, the reactive oxygen species fluorescence expanded to more areas of the radicle, reaching the root apical meristem. A storage time-dependent decrease in catalase activity, observed in both embryonic axes and cotyledons, was also positively correlated with germinability. DNA fragmentation was observed in beech seeds during storage and occurred predominantly in embryonic axes stored for 5 years and more. Altogether, these results suggest that the loss of germinability in beech seeds during long-term storage depends on several factors, including strong of reactive oxygen species accumulation accompanied by reduced catalase activity as well as membrane injury and DNA alternations, which may be aging-related and ROS-derived. We suggest that the accumulating reactive oxygen species that spread to the root apical meristem are key factors that affect seed germinability after long-term storage.

  14. Ethnolinguistic structuring of sorghum genetic diversity in Africa and the role of local seed systems.

    PubMed

    Westengen, Ola T; Okongo, Mark Atam; Onek, Leo; Berg, Trygve; Upadhyaya, Hari; Birkeland, Siri; Kaur Khalsa, Siri Dharma; Ring, Kristoffer H; Stenseth, Nils C; Brysting, Anne K

    2014-09-30

    Sorghum is a drought-tolerant crop with a vital role in the livelihoods of millions of people in marginal areas. We examined genetic structure in this diverse crop in Africa. On the continent-wide scale, we identified three major sorghum populations (Central, Southern, and Northern) that are associated with the distribution of ethnolinguistic groups on the continent. The codistribution of the Central sorghum population and the Nilo-Saharan language family supports a proposed hypothesis about a close and causal relationship between the distribution of sorghum and languages in the region between the Chari and the Nile rivers. The Southern sorghum population is associated with the Bantu languages of the Niger-Congo language family, in agreement with the farming-language codispersal hypothesis as it has been related to the Bantu expansion. The Northern sorghum population is distributed across early Niger-Congo and Afro-Asiatic language family areas with dry agroclimatic conditions. At a finer geographic scale, the genetic substructure within the Central sorghum population is associated with language-group expansions within the Nilo-Saharan language family. A case study of the seed system of the Pari people, a Western-Nilotic ethnolinguistic group, provides a window into the social and cultural factors involved in generating and maintaining the continent-wide diversity patterns. The age-grade system, a cultural institution important for the expansive success of this ethnolinguistic group in the past, plays a central role in the management of sorghum landraces and continues to underpin the resilience of their traditional seed system.

  15. Ethnolinguistic structuring of sorghum genetic diversity in Africa and the role of local seed systems

    PubMed Central

    Westengen, Ola T.; Okongo, Mark Atam; Onek, Leo; Berg, Trygve; Upadhyaya, Hari; Birkeland, Siri; Kaur Khalsa, Siri Dharma; Ring, Kristoffer H.; Stenseth, Nils C.; Brysting, Anne K.

    2014-01-01

    Sorghum is a drought-tolerant crop with a vital role in the livelihoods of millions of people in marginal areas. We examined genetic structure in this diverse crop in Africa. On the continent-wide scale, we identified three major sorghum populations (Central, Southern, and Northern) that are associated with the distribution of ethnolinguistic groups on the continent. The codistribution of the Central sorghum population and the Nilo-Saharan language family supports a proposed hypothesis about a close and causal relationship between the distribution of sorghum and languages in the region between the Chari and the Nile rivers. The Southern sorghum population is associated with the Bantu languages of the Niger-Congo language family, in agreement with the farming-language codispersal hypothesis as it has been related to the Bantu expansion. The Northern sorghum population is distributed across early Niger-Congo and Afro-Asiatic language family areas with dry agroclimatic conditions. At a finer geographic scale, the genetic substructure within the Central sorghum population is associated with language-group expansions within the Nilo-Saharan language family. A case study of the seed system of the Pari people, a Western-Nilotic ethnolinguistic group, provides a window into the social and cultural factors involved in generating and maintaining the continent-wide diversity patterns. The age-grade system, a cultural institution important for the expansive success of this ethnolinguistic group in the past, plays a central role in the management of sorghum landraces and continues to underpin the resilience of their traditional seed system. PMID:25225391

  16. Ethnolinguistic structuring of sorghum genetic diversity in Africa and the role of local seed systems.

    PubMed

    Westengen, Ola T; Okongo, Mark Atam; Onek, Leo; Berg, Trygve; Upadhyaya, Hari; Birkeland, Siri; Kaur Khalsa, Siri Dharma; Ring, Kristoffer H; Stenseth, Nils C; Brysting, Anne K

    2014-09-30

    Sorghum is a drought-tolerant crop with a vital role in the livelihoods of millions of people in marginal areas. We examined genetic structure in this diverse crop in Africa. On the continent-wide scale, we identified three major sorghum populations (Central, Southern, and Northern) that are associated with the distribution of ethnolinguistic groups on the continent. The codistribution of the Central sorghum population and the Nilo-Saharan language family supports a proposed hypothesis about a close and causal relationship between the distribution of sorghum and languages in the region between the Chari and the Nile rivers. The Southern sorghum population is associated with the Bantu languages of the Niger-Congo language family, in agreement with the farming-language codispersal hypothesis as it has been related to the Bantu expansion. The Northern sorghum population is distributed across early Niger-Congo and Afro-Asiatic language family areas with dry agroclimatic conditions. At a finer geographic scale, the genetic substructure within the Central sorghum population is associated with language-group expansions within the Nilo-Saharan language family. A case study of the seed system of the Pari people, a Western-Nilotic ethnolinguistic group, provides a window into the social and cultural factors involved in generating and maintaining the continent-wide diversity patterns. The age-grade system, a cultural institution important for the expansive success of this ethnolinguistic group in the past, plays a central role in the management of sorghum landraces and continues to underpin the resilience of their traditional seed system. PMID:25225391

  17. Synthesis and application of molecular probe for detection of hydroxyl radicals produced by Na125I and γ-rays in aqueous solution

    PubMed Central

    SINGH, AMARJIT; YANG, YONGLIANG; ADELSTEIN, S. JAMES; KASSIS, AMIN I.

    2010-01-01

    Purpose To synthesize N-(3-(3-aminopropylamino)propyl)-2-oxo-2H-chromene-3-carboxamide (7), a novel DNA-binding, coumarin-based, fluorescent hydroxylradical (·OH) indicator and to assess its quantum efficiency compared with that of coumarin-3-carboxylic acid (1) and N1,N12-bis[2-oxo-2H-chromene-3-carbonyl]- 1,12-diamine-4,9-diazadodecane (9). Materials and methods Using computer-generated molecular modeling, 7 and 9 and their respective 7-hydroxylated derivatives 8 and 10 were docked onto DNA dodecamer d(CGCGAATTCGCG)2, the ligand–DNA complexes were energy minimized, and binding free energies and inhibition constants were calculated. Compound 7 was judged an appropriate target molecule and was synthesized. Compounds 1, 7, and 9 were incubated with Na125I or irradiated with 137Cs γ-rays, and the influence of pH, dose, type of radiation, and the concentration of indicator on fluorescence yield were determined. Results Non-fluorescent 7 and 9 are converted to fluorescent, 7-hydroxylated derivatives 8 and 10 after interaction with ·OH in aqueous solution. For 1, 7, and 9, hydroxylation yield increases linearly with both Na125I dose (0–700 × 106 decays) and 137Cs dose (0–11.0 Gy). Fluorescence induction is significantly reduced at acidic pH and the fluorescent quantum yield of 8 is ~3 times that of 2 or 10 at pH 7.0. With Na125I incubation and γ-ray irradiation, the fluorescence signal of 7 increases linearly with concentration and saturates at ~50 μM. Conclusion Compound 7 quantifies lower concentrations of ·OH than do 1 and 9. This detector is therefore likely to be a good reporter of ·OH produced within a few nanometers of DNA. PMID:19061124

  18. Characterization and distribution of (125I)epidepride binding to dopamine D2 receptors in basal ganglia and cortex of human brain

    SciTech Connect

    Joyce, J.N.; Janowsky, A.; Neve, K.A. )

    1991-06-01

    The distribution and pharmacology of the binding of {sup 125}I-epidepride, a substituted benzamide with high affinity and selectivity for dopamine (DA) D2 receptors in rat brain is described in human brain. Saturation analysis of the binding of {sup 125}I-epidepride to membranes derived from striatum and regions of cortex demonstrated similar Kd values (34 and 28-33 pM, respectively) but differing maximum density of binding site values (152 and 3-8 fmol/mg of protein, respectively). The pharmacological profile of binding in cortex was also similar to striatum (epidepride greater than spiperone greater than butaclamol = flupenthixol greater than clozapine) except that an additional low-affinity site, blocked by the alpha-2 adrenergic antagonist idazoxan, was present in cortex. Quantification by autoradiography also demonstrated the greatest binding in the basal ganglia, with the striatum exhibiting greater binding than the pallidal complex or midbrain regions. For the pallidum, binding in the external segment was higher than the internal segment. Within the midbrain the binding of {sup 125}I-epidepride correlated well with the known distribution of DA-containing cell bodies, with the substantia nigra (pars compacta and pars lateralis) and ventral tegmental area (A10) higher than area A8 and central gray. Binding in frontal and parietal cortex was highest in the internal layers (layers V and VI). Temporal cortex showed a 2-fold higher density of binding than other cortical regions and a trilaminar pattern; binding was greater in the external (layers I and II) and internal layers than in the middle layers (III and IV). This pattern changed in the parahippocampal complex. Within the lateral occipitotemporal cortex, binding was densest in layers I to III and very low in layers IV to VI, but binding was almost nonexistent in the adjacent entorhinal cortex.

  19. Beta 1- and beta 2-adrenergic /sup 125/I-pindolol binding sites in the interpeduncular nucleus of the rat: Normal distribution and the effects of deafferentation

    SciTech Connect

    Battisti, W.P.; Artymyshyn, R.P.; Murray, M.

    1989-07-01

    The plasticity of the beta 1- and beta 2-adrenergic receptor subtypes was examined in the interpeduncular nucleus (IPN) of the adult rat. The beta-adrenergic receptor antagonist 125I-pindolol (125I-PIN) was used in conjunction with the selective subtype antagonists ICI 118,551 and ICI 89,406 to determine the subnuclear distribution of beta 1- and beta 2-adrenergic receptors in this nucleus and to correlate the receptor distribution with the distribution of both noradrenergic afferents from the locus coeruleus (LC) and non-noradrenergic afferents from the fasiculus retroflexus (FR). The density of these binding sites was examined following lesions that decreased (LC lesions) or increased (FR lesions) the density of the noradrenergic projection in the IPN. Quantitative radioautography indicated that beta 1-labeled binding sites account for the larger percentage of binding sites in the IPN. The beta 1-binding sites are densest in those subnuclei that receive a noradrenergic projection from the LC: the central, rostral, and intermediate subnuclei. beta 1-binding sites are algo homogeneously distributed throughout the lateral subnuclei, where there is no detectable noradrenergic innervation. beta 2-binding sites have a more restricted distribution. They are concentrated in the ventral half of the lateral subnuclei, where they account for 70% of total 125I-PIN binding sites. beta 2-binding sites are also present along the ventral border of the IPN. Some of this labeling extends into the central and intermediate subnuclei. Bilateral lesions of the LC, which selectively remove noradrenergic innervation to the IPN, result in an increase in the beta 1-binding sites. Bilateral lesions of the FR, which remove the major cholinergic and peptidergic input from the IPN, elicit an increase in noradrenergic projections and a decrease in beta 1-binding sites.

  20. Reaction of alpha-tubulin with iodotyrosines catalyzed by tubulin:tyrosine ligase: carboxy-terminal labeling of tubulin with ( sup 125 I)monoiodotyrosine

    SciTech Connect

    Joniau, M.; Coudijzer, K.; De Cuyper, M. )

    1990-02-01

    We have studied the capacity of different iodinated derivatives of phenylalanine and tyrosine to inhibit the incorporation of (3H)tyrosine into tubulin catalyzed by tubulin:tyrosine ligase. In contrast to thyronine and its iodinated derivatives, iodotyrosines were efficient inhibitors. That they also functioned as substrates of the enzyme was shown by the effective incorporation of (125I)mono- and diiodotyrosine into tubulin. The label was shown to be located at the carboxy terminus. Labeling by this method conserves the polymerization capacity of tubulin in contrast with classical radioiodination methods involving oxidation.

  1. Incidence and specificity of antibodies to types I, II, III, IV, and V collagen in rheumatoid arthritis and other rheumatic diseases as measured by 125I-radioimmunoassay

    SciTech Connect

    Stuart, J.M.; Huffstutter, E.H.; Townes, A.S.; Kang, A.H.

    1983-07-01

    Antibodies to human native and denatured types I, II, III, IV, and V collagens were measured using 125I-radioimmunoassay. Mean levels of binding by sera from 30 rheumatoid arthritis patients were significantly higher than those from 20 normal subjects against all of the collagens tested. The relative antibody concentration was higher in synovial fluid than in simultaneously obtained serum. Many patients with gout or various other rheumatic diseases also had detectable anticollagen antibodies. With a few notable exceptions, the majority of the reactivity detected in all patient groups was directed against covalent structural determinants present on all of the denatured collagens, suggesting a secondary reaction to tissue injury.

  2. Preparation of stable sup 125 I cyclic GMP tyrosine methyl ester suitable for 3',5' cyclic GMP radioimmunoassay by HPLC

    SciTech Connect

    Thompson, M.R.; Luttrell, M.; Giannella, R.A. )

    1990-01-01

    Determination of the concentration of cyclic guanosine monophosphate (cGMP) by radioimmunoassay (RIA) depends upon the availability of suitable radiolabeled tracers and antibody to detect the product. Reverse phase chromatographic techniques can easily separate the reaction products of chloramine-T iodination of succinyl cGMP tyrosine methyl ester. The binding characteristics of the iodination reaction products to anti-cGMP antibody have been determined. Purified succinyl cyclic nucleotide 125I-tyrosine methyl ester binds to cGMP antisera identically as commercially available tracer. The tracer is stable for greater than three months.

  3. Studies of the biogenic amine transporters. IV. Demonstration of a multiplicity of binding sites in rat caudate membranes for the cocaine analog [125I]RTI-55.

    PubMed

    Rothman, R B; Cadet, J L; Akunne, H C; Silverthorn, M L; Baumann, M H; Carroll, F I; Rice, K C; de Costa, B R; Partilla, J S; Wang, J B

    1994-07-01

    The drug 3 beta-[4'-iodophenyl]tropan-2 beta-carboxylic acid methyl ester (RTI-55) is a cocaine congener with high affinity for the dopamine transporter (Kd < 1 nM). The present study characterized [125I]RTI-55 binding to membranes prepared from rat, monkey and human caudates and COS cells transiently expressing the cloned rat dopamine (DA) transporter. Using the method of binding surface analysis, two binding sites were resolved in rat caudate: a high-capacity binding site (site 1, Bmax = 11,900 fmol/mg of protein) and a low-capacity site (site 2, Bmax = 846 fmol/mg of protein). The Kd (or Ki) values of selected drugs at the two sites were as follows: (Ki for high-capacity site and Ki for low-capacity site, respectively): RTI-55 (0.76 and 0.21 nM), 1-[2-diphenyl-methoxy)ethyl]-4-(3-phenylpropyl)piperazine (0.79 and 358 nM), mazindol (37.6 and 631 nM), 2 beta-carbomethoxy-3 beta-(4-fluorophenyl)tropane (45.0 and 540 nM) and cocaine (341 and 129 nM). Nisoxetine, a selective noradrenergic uptake blocker, had low affinity for both sites. Serotonergic uptake blockers had a high degree of selectivity and high affinity for the low-capacity binding site (Ki of citalopram = 0.38 nM; Ki of paroxetine = 0.033 nM). The i.c.v. administration of 5,7-dihydroxytryptamine to rats pretreated with nomifensine (to protect dopaminergic and noradrenergic nerve terminals) selectively decreased the Bmax of site 2, strongly supporting the idea that site 2 is a binding site on the serotonin (5-HT) transporter. This serotonergic lesion also increased the affinity of [125I]RTI-55 for the DA transporter by 10-fold. The ligand selectivity of the caudate 5-HT transporter was different from the [I125]RTI-55 binding site on the 5-HT transporter present in membranes prepared from whole rat brain minus caudate. The [125I]RTI-55 binding to the DA transporter was further resolved into two components, termed sites 1a and 1b, by using human and monkey (Macaca mulatta) caudate membranes but not the

  4. No effect of seed source on multiple aspects of ecosystem functioning during ecological restoration: cultivars compared to local ecotypes of dominant grasses.

    PubMed

    Baer, Sara G; Gibson, David J; Gustafson, Danny J; Benscoter, Allison M; Reed, Lewis K; Campbell, Ryan E; Klopf, Ryan P; Willand, Jason E; Wodika, Ben R

    2014-02-01

    Genetic principles underlie recommendations to use local seed, but a paucity of information exists on the genetic distinction and ecological consequences of using different seed sources in restorations. We established a field experiment to test whether cultivars and local ecotypes of dominant prairie grasses were genetically distinct and differentially influenced ecosystem functioning. Whole plots were assigned to cultivar and local ecotype grass sources. Three subplots within each whole plot were seeded to unique pools of subordinate species. The cultivar of the increasingly dominant grass, Sorghastrum nutans, was genetically different than the local ecotype, but genetic diversity was similar between the two sources. There were no differences in aboveground net primary production, soil carbon accrual, and net nitrogen mineralization rate in soil between the grass sources. Comparable productivity of the grass sources among the species pools for four years shows functional equivalence in terms of biomass production. Subordinate species comprised over half the aboveground productivity, which may have diluted the potential for documented trait differences between the grass sources to influence ecosystem processes. Regionally developed cultivars may be a suitable alternative to local ecotypes for restoration in fragmented landscapes with limited gene flow between natural and restored prairie and negligible recruitment by seed. PMID:24567751

  5. No effect of seed source on multiple aspects of ecosystem functioning during ecological restoration: cultivars compared to local ecotypes of dominant grasses

    PubMed Central

    Baer, Sara G; Gibson, David J; Gustafson, Danny J; Benscoter, Allison M; Reed, Lewis K; Campbell, Ryan E; Klopf, Ryan P; Willand, Jason E; Wodika, Ben R

    2014-01-01

    Genetic principles underlie recommendations to use local seed, but a paucity of information exists on the genetic distinction and ecological consequences of using different seed sources in restorations. We established a field experiment to test whether cultivars and local ecotypes of dominant prairie grasses were genetically distinct and differentially influenced ecosystem functioning. Whole plots were assigned to cultivar and local ecotype grass sources. Three subplots within each whole plot were seeded to unique pools of subordinate species. The cultivar of the increasingly dominant grass, Sorghastrum nutans, was genetically different than the local ecotype, but genetic diversity was similar between the two sources. There were no differences in aboveground net primary production, soil carbon accrual, and net nitrogen mineralization rate in soil between the grass sources. Comparable productivity of the grass sources among the species pools for four years shows functional equivalence in terms of biomass production. Subordinate species comprised over half the aboveground productivity, which may have diluted the potential for documented trait differences between the grass sources to influence ecosystem processes. Regionally developed cultivars may be a suitable alternative to local ecotypes for restoration in fragmented landscapes with limited gene flow between natural and restored prairie and negligible recruitment by seed. PMID:24567751

  6. Nanodosimetry of Auger electrons: A case study from the decay of 125I and 0-18-eV electron stopping cross sections of cytosine

    NASA Astrophysics Data System (ADS)

    Michaud, M.; Bazin, M.; Sanche, L.

    2013-03-01

    Radiopharmaceuticals emitting Auger electrons are often injected into patients undergoing cancer treatment with targeted radionuclide therapy (TRT). In this type of radiotherapy, the radiation source is radial and most of the emitted primary particles are low-energy electrons (LEEs) having kinetic energies distributed mostly from zero to a few hundred electron volts with very short ranges in biological media. These LEEs generate a high density of energy deposits and clustered damage, thus offering a relative biological effectiveness comparable to that of alpha particles. In this paper, we present a simple model and corresponding measurements to assess the energy deposited near the site of the radiopharmaceuticals in TRT. As an example, a calculation is performed for the decay of a single 125I radionuclide surrounded by a 1-nm-radius spherical shell of cytosine molecules using the energy spectrum of LEEs emitted by 125I along with their stopping cross sections between 0 and 18 eV. The dose absorbed by the cytosine shell, which occupies a volume of 4 nm3, is extremely high. It amounts to 79 kGy per decay of which 3%, 39%, and 58% is attributed to vibrational excitations, electronic excitations, and ionization processes, respectively.

  7. Monte Carlo calculated microdosimetric spread for cell nucleus-sized targets exposed to brachytherapy 125I and 192Ir sources and 60Co cell irradiation.

    PubMed

    Villegas, Fernanda; Tilly, Nina; Ahnesjö, Anders

    2013-09-01

    The stochastic nature of ionizing radiation interactions causes a microdosimetric spread in energy depositions for cell or cell nucleus-sized volumes. The magnitude of the spread may be a confounding factor in dose response analysis. The aim of this work is to give values for the microdosimetric spread for a range of doses imparted by (125)I and (192)Ir brachytherapy radionuclides, and for a (60)Co source. An upgraded version of the Monte Carlo code PENELOPE was used to obtain frequency distributions of specific energy for each of these radiation qualities and for four different cell nucleus-sized volumes. The results demonstrate that the magnitude of the microdosimetric spread increases when the target size decreases or when the energy of the radiation quality is reduced. Frequency distributions calculated according to the formalism of Kellerer and Chmelevsky using full convolution of the Monte Carlo calculated single track frequency distributions confirm that at doses exceeding 0.08 Gy for (125)I, 0.1 Gy for (192)Ir, and 0.2 Gy for (60)Co, the resulting distribution can be accurately approximated with a normal distribution. A parameterization of the width of the distribution as a function of dose and target volume of interest is presented as a convenient form for the use in response modelling or similar contexts.

  8. Lymphatic flow in humans as indicated by the clearance of /sup 125/I-labeled albumin from the subcutaneous tissue of the leg

    SciTech Connect

    Fernandez, M.J.; Davies, W.T.; Owen, G.M.; Tyler, A.

    1983-08-01

    Since the removal of albumin from the extracellular space and its return to the vascular compartment is the essential function of the lymphatic system, the rate at which it is removed from the interstitial tissue may be regarded as a means of estimating lymphatic efficiency. An objective measure of lymphatic function can be obtained by monitoring the rate of clearance following injection of /sup 125/I-labeled albumin (RIHSA) from the subcutaneous tissue of a limb. The clearance of /sup 125/I-RIHSA from lower limb was monitored in a group of patients with normal limbs, patients with unilateral edema due to deep vein thrombosis, and patients with bilateral edema due to hypoproteinemia. The mean T1/2 in normal legs was 32.7 hr, compared to 23.7 hr in edematous limbs due to deep vein thrombosis and 19.4 in edematous limbs due to hypoproteinemia. There is a clear-cut difference in clearance rate between edematous and nonedematous limbs. This suggests that lymphatic flow is increased in edema due to venous obstruction and hypoproteinemia.

  9. Nanodosimetry of Auger electrons: A case study from the decay of (125)I and 0-18-eV electron stopping cross sections of cytosine.

    PubMed

    Michaud, M; Bazin, M; Sanche, L

    2013-03-01

    Radiopharmaceuticals emitting Auger electrons are often injected into patients undergoing cancer treatment with targeted radionuclide therapy (TRT). In this type of radiotherapy, the radiation source is radial and most of the emitted primary particles are low-energy electrons (LEEs) having kinetic energies distributed mostly from zero to a few hundred electron volts with very short ranges in biological media. These LEEs generate a high density of energy deposits and clustered damage, thus offering a relative biological effectiveness comparable to that of alpha particles. In this paper, we present a simple model and corresponding measurements to assess the energy deposited near the site of the radiopharmaceuticals in TRT. As an example, a calculation is performed for the decay of a single (125)I radionuclide surrounded by a 1-nm-radius spherical shell of cytosine molecules using the energy spectrum of LEEs emitted by (125)I along with their stopping cross sections between 0 and 18 eV. The dose absorbed by the cytosine shell, which occupies a volume of 4 nm(3), is extremely high. It amounts to 79 kGy per decay of which 3%, 39%, and 58% is attributed to vibrational excitations, electronic excitations, and ionization processes, respectively.

  10. Development of beta 1 and beta 2 adrenergic receptors in baboon brain: an autoradiographic study using (/sup 125/I)iodocyanopindolol

    SciTech Connect

    Slesinger, P.A.; Lowenstein, P.R.; Singer, H.S.; Walker, L.C.; Casanova, M.F.; Price, D.L.; Coyle, J.T.

    1988-07-15

    (125I)iodocyanopindolol (ICYP) autoradiography was used to investigate the temporal development and distribution of beta 1 and beta 2 receptors in brains of baboons at ages embryonic day 100 (E100), full-term gestation (El80), and 3 years. In all brain regions examined, with the exception of the hippocampus, binding to beta 1 receptors exceeded that to beta 2 receptors. The highest densities of beta 1 receptors were found in the caudate nucleus, putamen, globus pallidus, substantia nigra, and cerebral cortex; intermediate receptor densities were observed in most nuclei of thalamus, and the lowest concentrations were in the hippocampus. At E100, beta receptors were identified in the striatum, globus pallidus, and thalamus. During maturation, the number of beta 1 receptors declined in cortical areas but increased in the head of the caudate and putamen. Significant differences in the developmental distribution of beta receptors during development were also detected: at E100 and E180 beta 1 receptors appeared as patches in the caudate and putamen, but by 3 years of age they were more homogeneously distributed in both regions; changes also occurred in the distribution of binding within cortical layers. Autoradiograms of (125I)ICYP and (3H)mazindol binding show overlapping patches of labeling in the E180 striatum, suggesting a possible developmental association between beta receptors and dopamine high-affinity uptake carrier sites. This study demonstrates that noradrenergic receptors in the primate forebrain undergo significant developmental reorganization with regional variations.

  11. Topographical linkage of tecto-thalamo-anterior ectosylvian sulcal cortex in the cat: an /sup 125/I-WGA autoradiographic study

    SciTech Connect

    Higo, S.; Kawamura, S.

    1984-06-01

    Following injection of /sup 125/I-WGA into various parts of the caudal thalamus in the cat, the distribution of orthograde and retrograde labels in the cortex around the anterior ectosylvian sulcus (AESS) and the superior colliculus (SC) was examined autoradiographically. When /sup 125/I-WGA injections involved the medial part of nucleus lateralis posterior (Lp) of the thalamus, both orthograde and retrograde labels consistently appeared in the cortex around AESS, and retrograde labels in the SC. The topographical organization of the cortical connections with the medial part of Lp can be well correlated with that of the tecto-thalamic projections, in such a way that the dorsal portion of the medial part of Lp which receives fibers from the rostromedial part of SC is connected reciprocally with the lateral lip of AESS and the crown of the anterior sylvian gyrus; whereas, the most ventral portion of the medial part of Lp which receives tectal afferents from the caudolateral part of SC is connected with the dorsal bank and fundus of AESS. These results suggest the existence of retinotopically ordered linkage between the tecto-Lp and the Lp-AESS connections in the cat.

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

    SciTech Connect

    Wagner, J.A.

    1987-01-01

    This dissertation provides molecular evidence for a diversity of Ca/sup 2 +/ channels in neuronal and non-neuronal tissues. First, I demonstrated specific, reversible, saturable binding sites for omega (/sup 125/I)conotoxin GVIA (omega(/sup 125/I)CTX) in rat brain and rabbit sympathetic ganglion. Omega (/sup 125/I)CTX binding has a unique pharmacology, ion selectivity, and anatomical distribution in rat brain. Omega (/sup 125/I)CTX binding was solubilized, retaining an appropriate pharmacology and ion selectivity. Omega(/sup 125/I)CTX binding may be associated with a Ca/sup 2 +/ channel because the K/sub D/ of omega (/sup 125/I)CTX is similar to the IC/sub 50/ of inhibition of depolarization-induced /sup 45/Ca/sup 2 +/ flux into rat brain synaptosomes. Specific (-)(/sup 3/H)desmethoxyverapamil ((-)(/sup 3/H)DMV) binding sites were demonstrated on osteoblast-like osteosarcoma cell membranes.

  13. Prescription dose in permanent {sup 131}Cs seed prostate implants

    SciTech Connect

    Yue Ning; Heron, Dwight E.; Komanduri, Krishna; Huq, M. Saiful

    2005-08-15

    Recently, {sup 131}Cs seeds have been introduced for prostate permanent seed implants. This type of seed has a relatively short half-life of 9.7 days and has its most prominent emitted photon energy peaks in the 29-34 keV region. Traditionally, 145 and 125 Gy have been prescribed for {sup 125}I and {sup 103}Pd seed prostate implants, respectively. Since both the half-life and dosimetry characteristics of {sup 131}Cs seed are quite different from those of {sup 125}I and {sup 103}Pd, the appropriate prescription dose for {sup 131}Cs seed prostate implant may well be different. This study was designed to use a linear quadratic radiobiological model to determine an appropriate dose prescription scheme for permanent {sup 131}Cs seed prostate implants. In this model, prostate edema was taken into consideration. Calculations were also performed for tumors of different doubling times and for other related radiobiological parameters of different values. As expected, the derived prescription dose values were dependent on type of tumors and types of edema. However, for prostate cancers in which tumor cells are relatively slow growing and are reported to have a mean potential doubling time of around 40 days, the appropriate prescription dose for permanent {sup 131}Cs seed prostate implants was determined to be: 127{sub -12}{sup +5}Gy if the experiences of {sup 125}I seed implants were followed and 121{sub -3}{sup +0}Gy if the experiences of {sup 103}Pd seed implants were followed.

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

    SciTech Connect

    Martinez, A.; Goffinet, D.R.; Fee, W.; Goode, R.; Cox, R.S.

    1983-03-15

    /sup 125/Iodine seeds either individually placed or inserted into absorbable Vicryl suture carriers were utilized in conjunction with surgery and external beam radiotherapy in an attempt to increase local control rates in patients with (1) advanced oropharyngeal and laryngopharyngeal cancers (T3-T4, N2-N3), (2) massive cervical lymphadenopathy (N3) and an unknown primary site and (3) locally recurrent head and neck cancers. Forty-eight patients were treated with 55 implants. The carotid artery was implanted in 15 patients, while seven patients had seeds inserted into the base of the skull region, and another three patients had implants near cranial nerves. Eighteen of the 48 patients were treated for cure. The actuarial survival at five years in this subgroup was 50%. The overall local control in the head and neck area was 58%. In this group no patients to date have had a local failure in the implanted volume. Seventeen patients with comparable stage of disease treated prior to 1974 with curative intent without /sup 125/I implants were analyzed retrospectively for comparison with the implanted patients. The actuarial survival of these patients was 18% and the overall head and neck control was 21%. These differences are statistically significant at a P value of 0.01 and 0.007, respectively. Seventeen patients received implants for local recurrence. The local control in the head and neck area was 50%; however, the 2.5 year actuarial survival was only 17%. The complication rate was 11% (six of 55 implants). The improved survival, the high local control, and the minimal complication rates in this series makes the intraoperative implantation of /sup 125/I seeds and effective adjunctive treatment to surgery and external beam irradiation.

  15. Quantification, localization and identification of selenium in seeds of canola and two mustard species compared to seed meals produced by hydraulic press

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Brassica plants accumulate selenium (Se), especially in seeds, when grown in soils laden with Se in the westside of the San Joaquin Valley. In this study, we attempt to accurately determine the forms of Se present in the Se-enriched products produced from plants grown for the phytomanagement of Se. ...

  16. Studies of the biogenic amine transporters. V. Demonstration of two binding sites for the cocaine analog [125I]RTI-55 associated with the 5-HT transporter in rat brain membranes.

    PubMed

    Silverthorn, M L; Dersch, C M; Baumann, M H; Cadet, J L; Partilla, J S; Rice, K C; Carroll, F I; Becketts, K M; Brockington, A; Rothman, R B

    1995-04-01

    Earlier work characterized the binding of the high-affinity cocaine analog 3 beta-(4-125iodophenyl)-tropane-2-carboxylic acid methyl ester ([125I]RTI-55) to membranes prepared from rat caudate. That investigation demonstrated that [125I]RTI-55-labeled serotonin (5-HT) transporters in addition to dopamine (DA) transporters and resolved [125I]RTI-55 binding to 5-HT transporters into two distinct components. In the present study, we characterized [125I]RTI-55 binding to membranes prepared from whole rat brain minus caudate. The first series of experiments established that [125I]RTI-55 labels both DA and 5-HT transporters and that 50 nM paroxetine and either 1000 nM 1-[2-(diphenylmethoxy)ethyl]-4-(3-phenylpropyl)homopiperazine (LR1111) or 500 nM (RTI-120) could be used to block [125I]RTI-55 binding to the 5-HT and DA transporters, thereby generating selective assay conditions for the DA and 5-HT transporters, respectively. Selective lesioning of dopaminergic and serotonergic neurons with intracerebroventricular 6-hydroxydopamine and 5,7-dihydroxytryptamine selectively decreased [125I]RTI-55 binding to DA and 5-HT transporters, respectively, thereby confirming the selectivity of the assay conditions. The ligand-selectivity pattern of the whole brain minus caudate 5-HT transporter correlated significantly with that of the caudate 5-HT transporter, although there were some striking differences for selected test agents. Additional experiments resolved [125I]RTI-55 binding to the 5-HT transporter into two components. A ligand-selectivity analysis of the two components failed to identify a highly selective test agent. In summary, the major findings of the present study are that [125I]RTI-55 labels both DA and 5-HT transporters in membranes prepared from whole brain minus caudate, that 50 nM paroxetine and either 1000 nM LR1111 or 500 nM RTI-120 can be used as a blocking agent to generate selective assay conditions for the DA and 5-HT transporters, respectively, and that [125

  17. Planting local seed for growth to nationwide E/PO efforts

    NASA Astrophysics Data System (ADS)

    Fox, N.; Beisser, K.; Mendez, F.; Cockrell, D.; Wilhide, B.

    The Johns Hopkins University Applied Physics Laboratory (JHU/APL) is the home to hundreds of scientists and engineers, all involved in research, design and implementation of space missions. Many of these people actively seek out ways to raise awareness and interest in the local community by visiting schools, giving public lectures and supporting events held at the laboratory. During the past few years, APL has begun to foster a number of firm partnerships with organizations to further these community opportunities and provide a test bed for both formal and informal education activities through the Space Department E/PO office One of our ongoing partnerships is with the Maryland Science Center in Baltimore. A continual challenge faced by museums is how to stay current and allow visitors to experience the immediacy and excitement of scientific discovery. To help meet these challenges, the Maryland Science Center houses "SpaceLink", the Nation's first space, science and astronomy update center. Part media center, part discovery room, and part newsroom, the exhibit is a multi-purpose Professional Development Site for educators and a "classroom of the future" for K 12 students. APL scientists and- engineers regularly support SpaceLink's flexible programming, including scientist in residence, monthly credited seminars for educators (Teachers' Thursdays), a menu of Classroom Programs on request, Distance Learning Teacher Presentations, and special Live Events to highlight mission milestones and space-related anniversaries. This allows the guest scientists and engineers to interact directly with the public. These events also compliment the APL exhibits housed at the Science Center. JHU/APL offers an exciting environment for the study of applications in space by hosting the annual Maryland Summer Center for Space Science sponsored by the Maryland State Department of Education. Rising 6t h and 7t h grade students learn to harness the power of technology and keep pace with

  18. Intravenous and standard immune serum globulin preparations interfere with uptake of /sup 125/I-C3 onto sensitized erythrocytes and inhibit hemolytic complement activity

    SciTech Connect

    Berger, M.; Rosenkranz, P.; Brown, C.Y.

    1985-02-01

    Antibody-sensitized sheep erythrocytes were used as a model to determine the effects of therapeutic immune serum globulin (ISG) preparations on the ability of this particulate activator to fix C3 and initiate hemolysis. Both standard and intravenous forms of ISG inhibit uptake of /sup 125/I-C3, presumably by competing for the deposition of ''nascent'' C3b molecules onto the erythrocytes. Both forms of ISG also inhibit hemolytic activity of whole serum or purified complement components. The inhibition appears to be a specific property of IgG itself, since similar inhibition was not caused by equivalent concentrations of human serum albumin, and was not affected by the buffer in which the ISG was dissolved. Interference with C3 uptake onto antibody-sensitized platelets and/or inhibition of hemolytic complement activity could contribute to the efficacy of high dose intravenous ISG in idiopathic thrombocytopenic purpura.

  19. Radioimmunoassays that use 125I-labeled protein A for determination of Histoplasma capsulatum-specific immunoglobulin G, A, and M class antibodies in histoplasmosis.

    PubMed Central

    Sprouse, R F; Caldwell, C W; Everett, E D

    1981-01-01

    A radioimmunoassay for determination of human immunoglobulin G, A, and M class antibodies to Histoplasma capsulatum is reported. Yeast-phase antigen from H. capsulatum was adsorbed onto polyvinyl chloride microtiter plates as the solid phase. Human antibodies were allowed to react with this antigen, followed by addition of rabbit anti-human alpha- or mu-heavy chain sera. 125I-labeled staphylococcal protein A was then added and allowed to bind the human and rabbit immunoglobulin G. With this technique, it is possible to evaluate individual human serum samples for antigen-specific classes of antibodies. This assay may be useful for monitoring the immune response in histoplasma infections. PMID:7462420

  20. Rapid agonist-induced loss of sup 125 I-. beta. -endorphin opioid receptor sites in NG108-15, but not SK-N-SH neuroblastoma cells

    SciTech Connect

    Cone, R.I.; Lameh, J.; Sadee, W. )

    1991-01-01

    The authors have measured {mu} and {delta} opioid receptor sites on intact SK-N-SH and NG108-15 neuroblastoma cells, respectively, in culture. Use of {sup 125}I-{beta}-endorphin ({beta}E) as a tracer, together with {beta}E(6-31) to block high-affinity non-opioid binding in both cell lines, permitted the measurement of cell surface {mu} and {delta} opioid receptor sites. Labeling was at {delta} sites in NG108-15 cells and predominantly at {mu} sites in SK-N-SH cells. Pretreatment with the {mu} and {delta} agonist, DADLE, caused a rapid loss of cell surface {delta} receptor sites in NG108-15 cells, but failed to reduce significantly {mu} receptor density in SK-N-SH cells.

  1. Inhibition of /sup 125/I-labeled ristocetin binding to Micrococcus luteus cells by the peptides related to bacterial cell wall mucopeptide precursors: quantitative structure-activity relationships

    SciTech Connect

    Kim, K.H.; Martin, Y.; Otis, E.; Mao, J.

    1989-01-01

    Quantitative structure-activity relationships (QSAR) of N-Ac amino acids, N-Ac dipeptides, and N-Ac tripeptides in inhibition of /sup 125/I-labeled ristocetin binding to Micrococcus luteus cell wall have been developed to probe the details of the binding between ristocetin and N-acetylated peptides. The correlation equations indicate that (1) the binding is stronger for peptides in which the side chain of the C-terminal amino acid has a large molar refractivity (MR) value, (2) the binding is weaker for peptides with polar than for those with nonpolar C-terminal side chains, (3) the N-terminal amino acid in N-Ac dipeptides contributes 12 times that of the C-terminal amino acid to binding affinity, and (4) the interactions between ristocetin and the N-terminal amino acid of N-acetyl tripeptides appear to be much weaker than those with the first two amino acids.

  2. /sup 125/I-DPDYN, monoiodo (D-Pro10)- dynorphin (1-11), is an effective and useful tool for the study of kappa opioid receptors

    SciTech Connect

    Gairin, J.E.; Jomary, C.; Cros, J.; Meunier, J.C.

    1986-01-01

    Iodination of the kappa-selective peptide DPDYN, (D-Pro10)-dynorphin (1-11), has been performed. The non radioactive monoiodo derivative of DPDYN retains kappa-selectivity (kappa/mu = 48 and kappa/delta = 140), despite a general but moderate decrease in affinity. Radioiodination of DPDYN leads to the monoiodinated peptide (S.A 700-800 Ci/mmol) which interacts specifically and reversibly with the kappa-sites in guinea-pig cerebellum membranes with high affinity (KD = 0.12-0.18 nM). In guinea-pig brain (mu-delta-kappa) and rabbit cerebellum (kappa much less than mu), /sup 125/I-DPDYN discriminates between kappa- and other (mu, delta) binding sites. We have used this new labelled probe for the direct, precise and rapid (exposure time less than 100 hours) visualization of kappa-sites in guinea-pig and rabbit cerebellar slices using autoradiography.

  3. Synthesis and pharmacological characterization of [125I]MRS1898, a high-affinity, selective radioligand for the rat A3 adenosine receptor

    PubMed Central

    Gao, Zhan-Guo; Teng, Bao; Wu, Haitao; Joshi, Bhalchandra V.; Griffiths, Gary L.

    2008-01-01

    A known selective agonist of the A3 adenosine receptors (AR), MRS1898 [(1′R,2′R,3′S,4′R,5′S)-4-{2-chloro-6-[(3-iodophenylmethyl)amino]purin-9-yl}-1-(methylaminocarbonyl)bicyclo[3.1.0]hexane-2,3-diol], was synthesized in radioactive form and characterized pharmacologically. This agonist ligand series, based on nucleoside analogues containing a rigid, bicyclic ring system in place of the ribose moiety, was selected for radiolabeling due to its high A3AR affinity across species, with nanomolar binding at both rat and human A3ARs. The radioiodination of MRS1898 on its N6–3-iodobenzyl substituent was accomplished in 76% radiochemical yield by iododestannylation of a 3-(trimethylstannyl)benzyl precursor. [125I]MRS1898 bound to the rat A3AR with a Kd value of 0.17 ± 0.04 nM and a Bmax value of 0.66 ± 0.15 pmol/mg protein. The competition binding profiles for other agonists and antagonists obtained with this radioligand are similar to those previously obtained with other radioligands. The advantages of [125I]MRS1898 compared with previously used radioligands are primarily its high selectivity and affinity for the rat A3AR and also its facile synthesis and radiochemical stability; however, a relatively high level of nonspecific binding presents a limitation. Thus, we have introduced the first selective radioligand for the rat A3AR. PMID:18528782

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

    SciTech Connect

    Thompson, Anna; Keyes, Mira; Pickles, Tom

    2010-10-01

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

  5. Lymphoblastoid cell supernatants increase expression of C3b receptors on human polymorphonuclear leucocytes: direct binding studies with 125I-C3b.

    PubMed Central

    Berger, M; Cross, A S

    1984-01-01

    Human PMN incubated in culture supernatants of the Raji long-term human lymphoblastoid cell line showed increased rosette formation with sheep erythrocytes coated with C3b (EIgM C4b3b) but no change in rosette formation with IgG-coated erythrocytes. This suggested a specific increase in cell surface C3b receptors, which was further investigated using 125I-C3b for direct binding studies. The results confirmed that specific binding of 125I-C3b to PMN incubated in culture supernatants increased up to three- to four-fold over binding to PMN incubated in control media alone. Scatchard analysis revealed that the apparent Ka for supernatant-treated cells, 3.36 +/- 0.89 X 10(7) L/M did not differ from the Ka for cells incubated in control media, 3.76 +/- 0.75 X 10(7) L/M, suggesting an increase in a single class of C3b receptors. Kinetic studies revealed that the active factor was present within 24 hr of culture of the Raji cells, and that neutrophils incubated in culture supernatants increased their C3b receptors continuously for up to 4 hr, the longest interval tested. The effect of the culture supernatant was lost with dilution beyond eight- to 10-fold. The results suggest that culture supernatants of this long-term lymphoblastoid cell line contain soluble factors that induce increased expression of C3b receptors on PMN and may thus serve as a model for study of important physiologic effects of lymphocyte products on PMN in vivo. PMID:6230308

  6. Cluster pattern analysis of energy deposition sites for the brachytherapy sources 103Pd, 125I, 192Ir, 137Cs, and 60Co.

    PubMed

    Villegas, Fernanda; Tilly, Nina; Bäckström, Gloria; Ahnesjö, Anders

    2014-09-21

    Analysing the pattern of energy depositions may help elucidate differences in the severity of radiation-induced DNA strand breakage for different radiation qualities. It is often claimed that energy deposition (ED) sites from photon radiation form a uniform random pattern, but there is indication of differences in RBE values among different photon sources used in brachytherapy. The aim of this work is to analyse the spatial patterns of EDs from 103Pd, 125I, 192Ir, 137Cs sources commonly used in brachytherapy and a 60Co source as a reference radiation. The results suggest that there is both a non-uniform and a uniform random component to the frequency distribution of distances to the nearest neighbour ED. The closest neighbouring EDs show high spatial correlation for all investigated radiation qualities, whilst the uniform random component dominates for neighbours with longer distances for the three higher mean photon energy sources (192Ir, 137Cs, and 60Co). The two lower energy photon emitters (103Pd and 125I) present a very small uniform random component. The ratio of frequencies of clusters with respect to 60Co differs up to 15% for the lower energy sources and less than 2% for the higher energy sources when the maximum distance between each pair of EDs is 2 nm. At distances relevant to DNA damage, cluster patterns can be differentiated between the lower and higher energy sources. This may be part of the explanation to the reported difference in RBE values with initial DSB yields as an endpoint for these brachytherapy sources.

  7. Cluster pattern analysis of energy deposition sites for the brachytherapy sources 103Pd, 125I, 192Ir, 137Cs, and 60Co

    NASA Astrophysics Data System (ADS)

    Villegas, Fernanda; Tilly, Nina; Bäckström, Gloria; Ahnesjö, Anders

    2014-09-01

    Analysing the pattern of energy depositions may help elucidate differences in the severity of radiation-induced DNA strand breakage for different radiation qualities. It is often claimed that energy deposition (ED) sites from photon radiation form a uniform random pattern, but there is indication of differences in RBE values among different photon sources used in brachytherapy. The aim of this work is to analyse the spatial patterns of EDs from 103Pd, 125I, 192Ir, 137Cs sources commonly used in brachytherapy and a 60Co source as a reference radiation. The results suggest that there is both a non-uniform and a uniform random component to the frequency distribution of distances to the nearest neighbour ED. The closest neighbouring EDs show high spatial correlation for all investigated radiation qualities, whilst the uniform random component dominates for neighbours with longer distances for the three higher mean photon energy sources (192Ir, 137Cs, and 60Co). The two lower energy photon emitters (103Pd and 125I) present a very small uniform random component. The ratio of frequencies of clusters with respect to 60Co differs up to 15% for the lower energy sources and less than 2% for the higher energy sources when the maximum distance between each pair of EDs is 2 nm. At distances relevant to DNA damage, cluster patterns can be differentiated between the lower and higher energy sources. This may be part of the explanation to the reported difference in RBE values with initial DSB yields as an endpoint for these brachytherapy sources.

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

    SciTech Connect

    Shiraishi, Yutaka; Yorozu, Atsunori; Ohashi, Toshio; Toya, Kazuhito; Saito, Shiro; Nishiyama, Toru; Yagi, Yasuto; Shigematsu, Naoyuki

    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.

  9. The angiotensin hexapeptide 3-8 fragment potently inhibits [125I]angiotensin II binding to non-AT1 or -AT2 recognition sites in bovine adrenal cortex.

    PubMed

    Jarvis, M F; Gessner, G W; Ly, C Q

    1992-08-25

    In the present studies, ligand competition experiments were conducted to examine the ability of angiotensin II peptide agonists and nonpeptide AT1- and AT2-selective receptor antagonists to inhibit the binding of [125I]angiotensin II to bovine adrenal cortical membranes. Angiotensin II, angiotensin III, the All-(3-8) hexapeptide fragment of angiotensin II, and the AT1-selective receptor antagonist L-158,809, inhibited [125I]angiotensin II binding in a biphasic fashion indicative of a ligand interaction at more than one recognition site. Approximately 20% of low affinity [125I]angiotensin II binding was inhibited only by high micromolar concentrations of L-158,809. RG 13647 (1(-1,4-benzodioxan-2-methyl)-5-diphenylacetyl-4,5,6,7-tetra hydro-1H-imidazo- [4,5,c]-pyridine-6-carboxylic acid) represents a potent and AT2-selective analog of PD 123177 and showed weak activity in competing for [125I]angiotensin II binding with an IC50 value of 100 microM. When subsequent competition studies were conducted in the presence of 1 microM L-158,809 to block [125I]angiotensin II to the AT1 receptor subtype, the angiotensin II agonists produced monophasic inhibition curves with AII-(3-8) showing the greatest activity (IC50 = 6 nM) followed by angiotensin III (IC50 = 15 nM) much greater than angiotensin II (IC50 = 110 nM). RG 13647 was not found to significantly inhibit this portion of [125I]angiotensin II binding. These data demonstrate that bovine adrenal cortex contains both the AT1 receptor subtype, as well as, a novel class of [125I]angiotensin II recognition sites which may be analogous to the recently described angiotensin IV (AT4) receptor.

  10. Is a Loose-Seed Nomogram Still Valid for Prostate Brachytherapy in a Stranded-Seed Era?

    SciTech Connect

    Kudchadker, Rajat J.; Swanson, David A.; Kuban, Deborah A.; Lee, Andrew K.; Bruno, Teresa L. C.; Frank, Steven J.

    2008-10-01

    Purpose: To characterize the amount of activity required to treat the prostate with stranded {sup 125}I radioactive seeds and compare our stranded data with the amount of activity recommended when individual seeds are implanted using a Mick applicator. Methods and Materials: Data from two groups of patients at University of Texas M. D. Anderson Cancer Center who were treated with prostate brachytherapy as monotherapy were analyzed. The first group included 100 patients implanted with individual seeds in 2000 and 2001. The second group comprised 81 patients for whom stranded seeds were implanted in 2006 and 2007. Seeds in both groups were {sup 125}I seeds with an air kerma strength of 0.497 U per seed (0.391 mCi per seed). The prescribed dose to planning target volume was 145 Gy. Results: The total implanted activity and the number of seeds used were significantly lower in the second group (p < 0.0001) than in the first group. The reduction in activity in the stranded-seed group was approximately 23% for a 20-cm{sup 3} prostate and approximately 15% for a 60-cm{sup 3} prostate. With equivalent activity between the two groups, the stranded-seed treatment covered a larger treatment volume with the prescribed dose. Conclusions: The amount of activity required to effectively treat a prostate of a given volume was lower with stranded seeds than with loose seeds. Our experience suggests that prostate brachytherapy that uses stranded seeds leads to a more efficient implant with fewer seeds and lower overall activity, resulting in improved homogeneity.

  11. Interleukin-1 receptors in mouse brain: Characterization and neuronal localization

    SciTech Connect

    Takao, T.; Tracey, D.E.; Mitchell, W.M.; De Souza, E.B. )

    1990-12-01

    The cytokine interleukin-1 (IL-1) has a variety of effects in brain, including induction of fever, alteration of slow wave sleep, and alteration of neuroendocrine activity. To examine the potential sites of action of IL-1 in brain, we used iodine-125-labeled recombinant human interleukin-1 (( 125I)IL-1) to identify and characterize IL-1 receptors in crude membrane preparations of mouse (C57BL/6) hippocampus and to study the distribution of IL-1-binding sites in brain using autoradiography. In preliminary homogenate binding and autoradiographic studies, (125I)IL-1 alpha showed significantly higher specific binding than (125I)IL-1 beta. Thus, (125I)IL-1 alpha was used in all subsequent assays. The binding of (125I)IL-1 alpha was linear over a broad range of membrane protein concentrations, saturable, reversible, and of high affinity, with an equilibrium dissociation constant value of 114 +/- 35 pM and a maximum number of binding sites of 2.5 +/- 0.4 fmol/mg protein. In competition studies, recombinant human IL-1 alpha, recombinant human IL-1 beta, and a weak IL-1 beta analog. IL-1 beta +, inhibited (125I)IL-1 alpha binding to mouse hippocampus in parallel with their relative bioactivities in the T-cell comitogenesis assay, with inhibitory binding affinity constants of 55 +/- 18, 76 +/- 20, and 2940 +/- 742 pM, respectively; rat/human CRF and human tumor necrosis factor showed no effect on (125I)IL-1 alpha binding. Autoradiographic localization studies revealed very low densities of (125I)IL-1 alpha-binding sites throughout the brain, with highest densities present in the molecular and granular layers of the dentate gyrus of the hippocampus and in the choroid plexus. Quinolinic acid lesion studies demonstrated that the (125I)IL-1 alpha-binding sites in the hippocampus were localized to intrinsic neurons.

  12. Seed localization in ultrasound and registration to C-arm fluoroscopy using matched needle tracks for prostate brachytherapy.

    PubMed

    Moradi, Mehdi; Mahdavi, S Sara; Dehghan, Ehsan; Lobo, Julio R; Deshmukh, Sanchit; Morris, William James; Fichtinger, Gabor; Salcudean, Septimiu Tim E

    2012-09-01

    We propose a novel fiducial-free approach for the registration of C-arm fluoroscopy to 3-D ultrasound images of prostate brachytherapy implants to enable dosimetry. The approach involves the reliable detection of a subset of radioactive seeds from 3-D ultrasound, and the use of needle tracks in both ultrasound and fluoroscopy for registration. Seed detection in ultrasound is achieved through template matching in 3-D radio frequency ultrasound signals, followed by thresholding and spatial filtering. The resulting subset of seeds is registered to the complete reconstruction of the brachytherapy implant from multiple C-arm fluoroscopy views. To compensate for the deformation caused by the ultrasound probe, simulated warping is applied to the seed cloud from fluoroscopy. The magnitude of the applied warping is optimized within the registration process. The registration is performed in two stages. First, the needle track projections from fluoroscopy and ultrasound are matched. Only the seeds in the matched needles are then used as fiducials for point-based registration. We report results from a physical phantom with a realistic implant (average postregistration seed distance of 1.6 ± 1.2 mm) and from five clinical patient datasets (average error: 2.8 ± 1.5 mm over 128 detected seeds). We conclude that it is feasible to use RF ultrasound data, template matching, and spatial filtering to detect a reliable subset of brachytherapy seeds from ultrasound to enable registration to fluoroscopy for dosimetry.

  13. Analysis of Recombinant Proteins in Transgenic Rice Seeds: Identity, Localization, Tolerance to Digestion, and Plant Stress Response.

    PubMed

    Wakasa, Yuhya; Takaiwa, Fumio

    2016-01-01

    Rice seeds are an ideal production platform for high-value recombinant proteins in terms of economy, scalability, safety, and stability. Strategies for the expression of large amounts of recombinant proteins in rice seeds have been established in the past decade and transgenic rice seeds that accumulate recombinant products such as bioactive peptides and proteins, which promote the health and quality of life of humans, have been generated in many laboratories worldwide. One of the most important advantages is the potential for direct oral delivery of transgenic rice seeds without the need for recombinant protein purification (downstream processing), which has been attributed to the high expression levels of recombinant products. Transgenic rice will be beneficial as a delivery system for pharmaceuticals and nutraceuticals in the future. This chapter introduces the strategy for producing recombinant protein in the edible part (endosperm) of the rice grain and describes methods for the analysis of transgenic rice seeds in detail. PMID:26614293

  14. Monte Carlo study of LDR seed dosimetry with an application in a clinical brachytherapy breast implant

    SciTech Connect

    Furstoss, C.; Reniers, B.; Bertrand, M. J.; Poon, E.; Carrier, J.-F.; Keller, B. M.; Pignol, J. P.; Beaulieu, L.; Verhaegen, F.

    2009-05-15

    A Monte Carlo (MC) study was carried out to evaluate the effects of the interseed attenuation and the tissue composition for two models of {sup 125}I low dose rate (LDR) brachytherapy seeds (Medi-Physics 6711, IBt InterSource) in a permanent breast implant. The effect of the tissue composition was investigated because the breast localization presents heterogeneities such as glandular and adipose tissue surrounded by air, lungs, and ribs. The absolute MC dose calculations were benchmarked by comparison to the absolute dose obtained from experimental results. Before modeling a clinical case of an implant in heterogeneous breast, the effects of the tissue composition and the interseed attenuation were studied in homogeneous phantoms. To investigate the tissue composition effect, the dose along the transverse axis of the two seed models were calculated and compared in different materials. For each seed model, three seeds sharing the same transverse axis were simulated to evaluate the interseed effect in water as a function of the distance from the seed. A clinical study of a permanent breast {sup 125}I implant for a single patient was carried out using four dose calculation techniques: (1) A TG-43 based calculation, (2) a full MC simulation with realistic tissues and seed models, (3) a MC simulation in water and modeled seeds, and (4) a MC simulation without modeling the seed geometry but with realistic tissues. In the latter, a phase space file corresponding to the particles emitted from the external surface of the seed is used at each seed location. The results were compared by calculating the relevant clinical metrics V{sub 85}, V{sub 100}, and V{sub 200} for this kind of treatment in the target. D{sub 90} and D{sub 50} were also determined to evaluate the differences in dose and compare the results to the studies published for permanent prostate seed implants in literature. The experimental results are in agreement with the MC absolute doses (within 5% for EBT

  15. Translocation of (125)I, (75)Se and (36)Cl to edible parts of radish, potato and green bean following wet foliar contamination under field conditions.

    PubMed

    Henner, P; Hurtevent, P; Thiry, Y; Levchuk, S; Yoschenko, V; Kashparov, V

    2013-10-01

    Specific translocation factor values (ftr) for (129)I, (79)Se and (36)Cl following foliar transfer are still missing from the IAEA reference databases. The translocation of the short-lived isotopes, (125)I, (75)Se, and (36)Cl, to radish, potato and green bean edible parts was measured under field conditions following acute and chronic wet foliar contamination at various plant growth stages in the absence of leaching caused by rain. The translocation factors obtained for (125)I ranged from 0.8 to 2.6% for radish, from 0.1 to 2.3% for potato and from 0.1 to 2.6% for bean. The translocation factors obtained for (75)Se ranged from 6.3 to 21% for radish, from 1.6 to 32.6% for potato and from 7.7 to 22.8% for bean (values similar to Cs or even higher). The translocation factors obtained for (36)Cl were close to those for (75)Se and ranged from 4.3 to 28.8% for radish, from 0.5 to 31.5% for potato and from 4.3 to 16.3% for bean. Iodide showed the lowest apparent mobility because of its preferential fixation in or on the leaves and a significant amount was probably volatilized. Selenite internal transfer was significant and possibly followed the sulfur metabolic pathway. Chloride was very mobile and quickly diffused throughout the plant. The translocation factors varied with the growth stage and depended on the development state of the edible tissue and its associated sink strength for nutrients and assimilates. For radish, translocation was high during the early vegetative stages. For potato, wheat and bean, a major peak in translocation was seen during the flowering growth stage and the concomitant growth of potato tubers. An additive effect of successive contamination events on translocated elements was shown in radish but not in bean and potato. The highest translocation value obtained for an acute contamination event was shown to be an adequate, conservative indicator of chronic contamination in absence of specific values. Due to the absence of rain leaching during

  16. Sliding slice: A novel approach for high accuracy and automatic 3D localization of seeds from CT scans

    SciTech Connect

    Tubic, Dragan; Beaulieu, Luc

    2005-01-01

    We present a conceptually novel principle for 3D reconstruction of prostate seed implants. Unlike existing methods for implant reconstruction, the proposed algorithm uses raw CT data (sinograms) instead of reconstructed CT slices. Using raw CT data solves several inevitable problems related to the reconstruction from CT slices. First, the sinograms are not affected by reconstruction artifacts in the presence of metallic objects and seeds in the patient body. Second, the scanning axis is not undersampled as in the case of CT slices; as a matter of fact the scanning axis is the most densely sampled and each seed is typically represented by several hundred samples. Moreover, the shape of a single seed in a sinogram can be modeled exactly, thus facilitating the detection. All this allows very accurate 3D reconstruction of both position and the orientation of the seeds. Preliminary results indicate that the seed position can be estimated with 0.15 mm accuracy (average), while the orientation estimate accuracy is within 3 deg. on average. Although the main contribution of the paper is to present a new principle of reconstruction, a preliminary implementation is also presented as a proof of concept. The implemented algorithm has been tested on a phantom and the obtained results are presented to validate the proposed approach.

  17. Studies of the biogenic amine transporters. VI. Characterization of a novel cocaine binding site, identified with [125I]RTI-55, in membranes prepared from whole rat brain minus caudate.

    PubMed

    Rothman, R B; Silverthorn, M L; Baumann, M H; Goodman, C B; Cadet, J L; Matecka, D; Rice, K C; Carroll, F I; Wang, J B; Uhl, G R

    1995-07-01

    Previous studies showed that the cocaine analog [125I]RTI-55 labels dopamine and serotonergic (5-HT) biogenic amine transporters (BATs) with high affinity. Here we characterized [125I]RTI-55 binding to membranes prepared from whole rat brain minus the caudate nuclei. Paroxetine (50 nM) was used to block [125I]RTI-55 binding to 5-HT transporter sites. Initial experiments identified drugs that displaced [125I]RTI-55 binding with moderately low slope factors. Binding surface analysis of the interaction of 3 beta-(4-chlorophenyl)tropan-2 beta-carboxylic acid phenyl ester hydrochloride (RTI-113) and 3 beta-(4-iodophenyl)tropan-2 beta-carboxylic acid phenyl ester hydrochloride (RTI-122) with [125I]RTI-55 binding sites readily resolved two binding sites for [125I]RTI-55 with Kd values of 0.44 nM and 17 nM and Bmax values of 31 and 245 fmol/mg protein. Potent 5-HT and noradrenergic uptake inhibitors had low affinity for both sites. Whereas cocaine, CFT and WIN35,065-2 were 6.0-, 25- and 14-fold selective for the first site, benztropine, PCP and the novel pyrrole, (+-)-(2RS,3aSR,8bRS)-1,2,3,3a,4,8b-hexahydro- 2-benzyl-1-methylindeno-[1,2-b]pyrrole resorcylate [(+-)-HBMP, formerly called (+-)-RTI-4793-14], were moderately selective for the second site. A single binding site with the characteristics of site 1 was resolved using COS cells transiently expressing the cloned rat dopamine transporter. Lesion studies with 6-hydroxydopamine and 5,7-dihydroxytryptamine were conducted to test the hypothesis that site 1 and site 2 are physically distinct. The data showed that these neurotoxins differentially decreased [125I]RTI-55 binding to sites 1 and 2. The differential distribution of sites 1 and 2 in rat brain provides further support for this hypothesis. Viewed collectively, these data show that [125I]RTI-55 labels a novel binding site in rat brain membranes, termed DATsite2, which is not associated with the classic dopamine, serotonin or norepinephrine transporters.

  18. Clinical value of dual-isotope fat absorption test system (FATS) using glycerol (/sup 125/I)trioleate and glycerol (/sup 75/Se)triether

    SciTech Connect

    Lembcke, B.; Loesler, A.C.; Caspary, W.F.; Schuernbrand, P.E.; Emrich, D.; Creutzfeldt, W.

    1986-08-01

    In order to delineate the clinical value of a dual-isotope fat absorption test system (FATS) using glycerol (/sup 75/Se)triether as lipid-phase marker and glycerol (/sup 125/I)trioleate as the test lipid, fecal isotope ratios from single stools (and a 72-hr stool homogenate) were compared to quantitative fecal fat excretion. The study included 11 patients without and 24 patients with steatorrhea. With a figure of 0.8% as the upper limit of normal, the test was a reliable indicator of steatorrhea with 87.5% sensitivity and 81.8% specificity; efficiency was 85.7%. Related to a prevalence of steatorrhea of 45.9% as the mean value of 1269 consecutive 72-hr specimens investigated for steatorrhea during 1978-1982, the positive (negative) predictive value of the FATS is 80.3% (87.2%). With 2% as the upper limit of normal, no false positive results ensued. It is concluded that a two-step interpretation of the FATS (0.8% limit and 2% limit) may be regarded a valid qualitative index for steatorrhea. The FATS isotope ratio using single stools correlated well with FATS ratios in the 72-hr stool homogenates (r = 0.97). FATS therefore allows a convenient estimate of steatorrhea from measuring single stools. As a quantitative measure of fecal fat excretion, the FATS is unreliable.

  19. Macrophage function as studied by the clearance of /sup 125/I-labeled polyvinylpyrrolidone in iron-deficient and iron-replete mice

    SciTech Connect

    Kuvibidila, S.; Wade, S.

    1987-01-01

    This study evaluated the effects of iron deficiency and iron repletion on in vivo macrophage function determined by the clearance of /sup 125/I-labeled polyvinylpyrrolidone (PVP). Two experiments were done. There were four groups of C57BL/6 female mice in experiment 1: the iron-deficient (ID), pair-fed (PF), control (C) and the high iron (HI) groups. In experiment 2, there were three ID groups (severe to moderate anemia), three PF, one C and four ID groups that were fed adequate iron for 14 (R-14), 7 (R-7), 3 (R-3) days before or on the day of PVP injection (R-0). The overall rate of PVP clearance from blood was lower in ID than in C or PF groups. This clearance is expressed by a constant, K, calculated from natural log (ln) of the cpm and the time postadministration of PVP that blood was drawn. The theoretical individual macrophages function (alpha PVP), derived from K and the weights of body, spleen and liver, was also lower in ID than in C or PF groups. The impairment was most severe with the most severe iron deficiency. Repletion for 7 to 15 d before PVP administration resulted in a partial correction of the clearance. Moderate undernutrition in the PF group had no effect.

  20. Altered binding of /sup 125/I-labeled calmodulin to a 46. 5-kilodalton protein in skin fibroblasts cultured from patients with cystic fibrosis

    SciTech Connect

    Tallant, E.A.; Wallace, R.W.

    1987-02-01

    The levels of calmodulin and calmodulin-binding proteins have been determined in cultured skin fibroblasts from patients with cystic fibrosis (CF) and age- and sex-matched controls. Calmodulin ranged from 0.20 to 0.76 microgram/mg protein; there was no difference between calmodulin concentration in fibroblasts from CF patients and controls. Calmodulin-binding proteins of 230, 212, 204, 164, 139, 70, 59, 46.5, and 41 kD were identified. A protein with a mobility identical to the 59-kD calmodulin-binding protein was labeled by antiserum against calmodulin-dependent phosphatase. Although Ca/sup 2 +//calmodulin-dependent phosphatase activity was detected, there was no different in activity between control and CF fibroblasts or in the level of phosphatase protein as determined by radioimmunoassay. Lower amounts of /sup 125/I-calmodulin were bound to the 46.5-kD calmodulin-binding protein in CF fibroblasts as compared with controls. The 46.5-kD calmodulin-binding protein may be reduced in CF fibroblasts or its structure may be altered resulting in a reduced binding capacity and/or affinity for calmodulin and perhaps reflecting, either directly or indirectly, the genetic defect responsible for cystic fibrosis.

  1. Binding of /sup 125/I-labeled endotoxin to bovine, canine, and equine platelets and endotoxin-induced agglutination of canine platelets

    SciTech Connect

    Meyers, K.M.; Boehme, M.; Inbar, O.

    1982-10-01

    Endotoxin from Escherichia coli O127:B8, Salmonella abortus-equi and S minnesota induced clumping of some canine platelets (PLT) at a final endotoxin concentration of 1 microgram/ml. Endotoxin-induced clumping of canine PLT was independent of PLT energy-requiring processes, because clumping was observed with canine PLT incubated with 2-deoxy-D-glucose and antimycin A. The PLT responded to adenosine diphosphate before, but not after, incubation with the metabolic inhibitors. Endotoxin induced a slight and inconsistant clumping of bovine and equine PLT at high (mg/ml) endotoxin concentration. High-affinity binding sites could not be demonstrated on canine, bovine, and equine PLT, using /sup 125/I-labeled E coli O127:B8 endotoxin. Nonspecific binding was observed and appeared to be due primarily to an extraneous coat on the PLT surface that was removed by gel filtration. The endotoxin that was bound to PLT did not appear to modify PLT function. An attempt to identify plasma proteins that bound physiologically relevant amounts of endotoxin was not successful. The significance of the endotoxin-induced clumping or lack of it on the pathophysiology of endotoxemia is discussed.

  2. Astatine-211 labeling of an antimelanoma antibody and its Fab fragment using N-succinimidyl p-astatobenzoate: comparisons in vivo with the p-[125I]iodobenzoyl conjugate.

    PubMed

    Hadley, S W; Wilbur, D S; Gray, M A; Atcher, R W

    1991-01-01

    Astatine-211 labeling of an antimelanoma antibody, NR-ML-05, and its Fab fragment with N-succinimidyl p-[211At]astatobenzoate (2a) has been described. Preparation of the astatinated intermediate 2a was accomplished by distilling astatine-211 from an irradiated bismuth target directly into a reaction mixture containing an organometallic compound, N-succinimidyl p-(tri-n-butylstannyl)benzoate (1), and an oxidant, N-chlorosuccinimide, in 5% HOAc/MeOH. Trapping of distilled astatine as 2a was found to be efficient, resulting in 70-90% yields based on the amount of astatine-211 in the reaction mixture. The dry distillation technique employed gave recoveries of astatine-211 which ranged from 20% to 75%. Conjugation of 2a to NR-ML-05 and its Fab fragment was accomplished in 40-60% yields. The [211At]astatobenzoyl-conjugated antibodies were found to be stable in vitro when challenged by strong denaturants and nucleophilic reagents. Coinjected dual-labeled studies of the 2a astatinated antibodies and the same antibodies labeled with N-succinimidyl p-[125I]iodobenzoate (2b) in athymic mice bearing the human tumor xenograft A375 Met/Mix demonstrated that both radiolabeled antibodies had equivalent tumor localization. Data from the dual-labeled biodistribution of the intact antibody suggests that the astatine is stably attached. Data from the dual-labeled Fab fragment suggests that a portion of the astatine label is released as astatide, either from the astatinated Fab or from a catabolite.

  3. (D-Pen2,4 prime -125I-Phe4,D-Pen5)enkephalin: A selective high affinity radioligand for delta opioid receptors with exceptional specific activity

    SciTech Connect

    Knapp, R.J.; Sharma, S.D.; Toth, G.; Duong, M.T.; Fang, L.; Bogert, C.L.; Weber, S.J.; Hunt, M.; Davis, T.P.; Wamsley, J.K. )

    1991-09-01

    (D-Pen2,4{prime}-125I-Phe4,D-Pen5)enkephalin ((125I)DPDPE) is a highly selective radioligand for the delta opioid receptor with a specific activity (2200 Ci/mmol) that is over 50-fold greater than that of tritium-labeled DPDPE analogs. (125I)DPDPE binds to a single site in rat brain membranes with an equilibrium dissociation constant (Kd) value of 421 {plus minus} 67 pM and a receptor density (Bmax) value of 36.4 {plus minus} 2.7 fmol/mg protein. The high affinity of this site for delta opioid receptor ligands and its low affinity for mu or kappa receptor-selective ligands are consistent with its being a delta opioid receptor. The distribution of these sites in rat brain, observed by receptor autoradiography, is also consistent with that of delta opioid receptors. Association and dissociation binding kinetics of 1.0 nM (125I) DPDPE are monophasic at 25 degrees C. The association rate (k + 1 = 5.80 {plus minus} 0.88 {times} 10(7) M-1 min-1) is about 20- and 7-fold greater than that measured for 1.0 nM (3H) DPDPE and 0.8 nM (3H) (D-Pen2,4{prime}-Cl-Phe4, D-Pen5)enkephalin, respectively. The dissociation rate of (125I)DPDPE (0.917 {plus minus} 0.117 {times} 10(-2) min-1) measured at 1.0 nM is about 3-fold faster than is observed for either of the other DPDPE analogs. The rapid binding kinetics of (125I)DPDPE is advantageous because binding equilibrium is achieved with much shorter incubation times than are required for other cyclic enkephalin analogs. This, in addition to its much higher specific activity, makes (125I)DPDPE a valuable new radioligand for studies of delta opioid receptors.

  4. Pharmacokinetics of internally labeled monoclonal antibodies as a gold standard: comparison of biodistribution of /sup 75/Se-, /sup 111/In-, and /sup 125/I-labeled monoclonal antibodies in osteogenic sarcoma xenografts in nude mice

    SciTech Connect

    Koizumi, M.; Endo, K.; Watanabe, Y.; Saga, T.; Sakahara, H.; Konishi, J.; Yamamuro, T.; Toyama, S.

    1989-04-01

    In order to know the true biodistribution of anti-tumor monoclonal antibodies, three monoclonal antibodies (OST6, OST7, and OST15) against human osteosarcoma and control antibody were internally labeled with 75Se by incubating (75Se)methionine and hybridoma cells. 75Se-labeled monoclonal antibodies were evaluated both in vitro and in vivo using the human osteogenic sarcoma cell line KT005, and the results were compared with those of 125I- and 111In-labeled antibodies. 75Se-, 125I- and 111In-labeled monoclonal antibodies had identical binding activities to KT005 cells, and the immunoreactivity was in the decreasing order of OST6, OST7, and OST15. On the contrary, in vivo tumor uptake (% injected dose/g) of 75Se- and 125I-labeled antibodies assessed using nude mice bearing human osteosarcoma KT005 was in the order of OST7, OST6, and OST15. In the case of 111In, the order was OST6, OST7, and OST15. High liver uptake was similarly seen with 75Se- and 111In-labeled antibodies, whereas 125I-labeled antibodies showed the lowest tumor and liver uptake. These data indicate that tumor targeting of antibody conjugates are not always predictable from cell binding studies due to the difference of blood clearance of labeled antibodies. Furthermore, biodistribution of both 111In- and 125I-labeled antibodies are not identical with internally labeled antibody. Admitting that internally labeled antibody is a ''gold standard'' of biodistribution of monoclonal antibody, high liver uptake of 111In-radiolabeled antibodies may be inherent to antibodies. Little, if any, increase in tumor-to-normal tissue ratios of antibody conjugates will be expected compared to those of 111In-labeled antibodies if stably coupled conjugates are administered i.v.

  5. Observations on the reactions between D-positive red cells and [125I]IgM anti-D molecules and subunits

    PubMed Central

    Holburn, A. M.; Cartron, J. P.; Economidou, Joanna; Gardner, Brigitte; Hughes-Jones, N. C.

    1971-01-01

    The method of preparation of partially purified [125I]IgM anti-D and of subunits of 180,000, 90,000 and 40,000 molecular weight with anti-D activity is described. It was found that approximately 11,500 whole IgM anti-D molecules would bind to each red cell of phenotype R1R2. On the other hand, approximately 31,000 molecules of both whole IgG anti-D and an IgM anti-D subunit of molecular weight 40,000 would bind to the same cell. The following possibilities are proposed to explain these findings: (1) IgM anti-D molecules bound to the red cell sterically hinder binding of other IgM antibody molecules to closely adjacent D-antigen sites and (2) some D-antigen sites are too far below the surface of the red cell to permit binding by the large IgM molecule. The average values of the equilibrium constants (K0) of two different examples of IgM anti-D were 1.7×109 and 2.5×109 litres/mole, and of the IgG antibodies obtained from the same plasmas were 9- and 32-fold lower respectively. The K0 of the IgM subunits was on average 23-fold lower than that of the whole IgM and it is concluded that IgM anti-D binds bivalently to each red cell but that the binding energy of one of the sites is relatively small. PMID:4998630

  6. Suppression of 125I-uptake in mouse thyroid by seaweed feeding: possible preventative effect of dietary seaweed on internal radiation injury of the thyroid by radioactive iodine.

    PubMed

    Maruyama, H; Yamamoto, I

    1992-12-01

    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 beta-carotene, such as kelps or laver supplemented with inorganic iodine, may be effective in prevention of internal radiation injury of the thyroid. PMID:1344008

  7. The endothelin ET(B) receptor agonist [125I]BQ-3020 binds predominantly to nerves in the bovine retractor penis muscle and penile artery.

    PubMed

    Parkkisenniemi, U M; Palkama, A; Virtanen, I; Klinge, E

    2000-11-01

    Preliminary pharmacological experiments have suggested that in the bovine retractor penis muscle there are relaxation-mediating endothelin ET(B) receptors, at least part of which are located on the inhibitory nitrergic nerves. The present work was undertaken to test this hypothesis by means of receptor autoradiography and additional pharmacological experiments. In the retractor penis muscle and the penile artery, specific binding of the ETB receptor-selective agonist [125I]BQ-3020 took place predominantly to nerve trunks and minor nerve branches. The situation was the same in the dorsal metatarsal artery, that was included as a reference because of its different innervation. Throughout the nerves the silver grains were evenly distributed over the nuclei of Schwann cells and the spaces between them. In the retractor penis there was also a small amount of specific binding to smooth muscle. No specific endothelial binding was observed in any of the tissues examined. The pharmacological studies confirmed that the relaxation of the retractor penis muscle induced by the ET(B) receptor-selective agonist, sarafotoxin S6c, is susceptible to tetrodotoxin as well as to inhibition of nitric oxide synthase. The relaxation was also characterized by inconsistency, weakness and tachyphylaxis. The electrical field stimulation-induced submaximal relaxation of the retractor penis was unaffected by stimulation or blockade of ET(B) receptors. The autoradiography suggests that in all the three bovine tissues studied there are ET(B) receptors located on nerves independently of the type of efferent nerve. The pharmacological experiments do not support the concept that in the bovine retractor penis muscle neuronal ET(B) receptors exert important immediate effects on the functioning of the penile erection-mediating nitrergic nerves.

  8. Prophylactic tamsulosin (Flomax) in patients undergoing prostate {sup 125}I brachytherapy for prostate carcinoma: Final report of a double-blind placebo-controlled randomized study

    SciTech Connect

    Elshaikh, Mohamed A.; Ulchaker, James C.; Reddy, Chandana A.; Angermeier, Kenneth W.; Klein, Eric A.; Chehade, Nabil; Altman, Andrew; Ciezki, Jay P. . E-mail: ciezkj@ccf.org

    2005-05-01

    Purpose: To evaluate the effectiveness of prophylactic tamsulosin (Flomax) in reducing the urinary symptoms in patients undergoing {sup 125}I prostate implantation (PI) for prostate adenocarcinoma. Methods and materials: This is a single-institution, double-blind, placebo-controlled, randomized trial for patients undergoing PI for prostate adenocarcinoma comparing prophylactic tamsulosin versus placebo. Eligibility criteria included patients not taking tamsulosin or other {alpha}-blockers treated with PI. The patients were randomly assigned to either tamsulosin (0.8 mg, orally once a day) or matched placebo. All patients started the medication 4 days before PI and continued for 60 days. The American Urologic Association (AUA) symptom index questionnaire was used to assess urinary symptoms. The AUA questionnaire was administered before PI for a baseline score and weekly for 8 weeks after PI. Patients were taken off the study if they developed urinary retention, had intolerable urinary symptoms, or wished to discontinue with the trial. Results: One hundred twenty-six patients were enrolled in this study from November 2001 to January 2003 (118 were evaluable: 58 in the tamsulosin arm and 60 in the placebo group). Pretreatment and treatment characteristics were comparably matched between the two groups. The urinary retention rate was 17% (10 patients) in the placebo group compared with 10% (6 patients) in the tamsulosin group (p = 0.3161). Eighty-eight percent (14 patients) of those who developed urinary retention experienced it within 2 weeks after the PI. Intolerable urinary symptoms were reported equally (10 patients in each group) with 70% occurring in the first 2 weeks after PI. There was a significant difference in mean AUA score in favor of tamsulosin at Week 5 after PI (p = 0.03). Conclusions: Prophylactic tamsulosin (0.8 mg/day) before prostate brachytherapy did not significantly affect urinary retention rates, but had a positive effect on urinary morbidity at

  9. Pharmacokinetics of ( sup 125 I)-2-iodo-3,7,8-trichlorodibenzo-p-dioxin in mice: Analysis with a physiological modeling approach

    SciTech Connect

    Leung, H.W.; Poland, A.; Paustenbach, D.J.; Murray, F.J.; Andersen, M.E. )

    1990-05-01

    2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) is a potent inducer of hepatic microsomal enzymes. The influence of an inducing dose of TCDD on tissue distribution and other pharmacokinetic behavior of a TCDD analog in the mice was examined by employing a high specific activity radioligand. (125I)-2-iodo-3,7,8-trichlorodibenzo-p-dioxin (ITCDD). Female C57BL/6J mice were pretreated with 0.1 mumol/kg of TCDD or the vehicle only, followed by 0.1 nmol ITCDD/kg 3 days later. The control animals had the highest concentration of ITCDD-derived radioactivity in the fat, but the TCDD-pretreated animals had the highest concentration in their livers. Whole-body elimination of ITCDD approximated first-order behavior, and induction by pretreatment with the inducing dose of TCDD almost doubled the rate of excretion (control mice, t1/2 = 14.2 days; pretreated mice, t1/2 = 8.0 days). All disposition results in naive and pretreated mice were satisfactorily described by a consistent physiologically based pharmacokinetic model in which induction increased the amount of microsomal ITCDD-binding protein from 1.75 to 20 nmol/liver and increased the rate constant for metabolism of free ITCDD from 1 to 3/hr/kg liver. The binding affinity of the microsomal ITCDD-binding protein was the same (20 nM) in both induced and noninduced mice. Model simulations indicated a time delay in the elimination of nonparent ITCDD metabolites from the body and a more rapid absorption of the parent ligand in the pretreated mice. Consistent with previous physiological modeling with TCDD in different mouse strains, the primary factor influencing the liver/fat concentration ratio appears to be the affinity and capacity of the microsomal TCDD-binding proteins, which are altered by induction.

  10. Comparison of Prophylactic Naftopidil, Tamsulosin, and Silodosin for {sup 125}I Brachytherapy-Induced Lower Urinary Tract Symptoms in Patients With Prostate Cancer: Randomized Controlled Trial

    SciTech Connect

    Tsumura, Hideyasu; Satoh, Takefumi; Ishiyama, Hiromichi; Tabata, Ken-ichi; Kotani, Shouko; Minamida, Satoru; Kimura, Masaki; Fujita, Tetsuo; Matsumoto, Kazumasa; Kitano, Masashi; Hayakawa, Kazushige; Baba, Shiro

    2011-11-15

    Purpose: To compare the efficacy of three {alpha}{sub 1A}/{alpha}{sub 1D}-adrenoceptor (AR) antagonists-naftopidil, tamsulosin, and silodosin-that have differing affinities for the {alpha}{sub 1}-AR subtypes in treating urinary morbidities in Japanese men with {sup 125}I prostate implantation (PI) for prostate cancer. Methods and Materials: This single-institution prospective randomized controlled trial compared naftopidil, tamsulosin, and silodosin in patients undergoing PI. Patients were randomized and received either naftopidil, tamsulosin, or silodosin. Treatment began 1 day after PI and continued for 1 year. The primary efficacy variables were the changes in total International Prostate Symptom Score (IPSS) and postvoid residual urine (PVR). The secondary efficacy variables were changes in IPSS storage score and IPSS voiding score from baseline to set points during the study (1, 3, 6, and 12 months). Results: Two hundred twelve patients were evaluated in this study between June 2006 and February 2009: 71, 70, and 71 patients in the naftopidil, tamsulosin, and silodosin groups, respectively. With respect to the primary efficacy variables, the mean changes in the total IPSS at 1 month after PI in the naftopidil, tamsulosin, and silodosin groups were +10.3, +8.9, and +7.5, respectively. There were significantly greater decreases with silodosin than naftopidil at 1 month in the total IPSS. The mean changes in the PVR at 6 months were +14.6, +23.7, and +5.7 mL in the naftopidil, tamsulosin, and silodosin groups, respectively; silodosin showed a significant improvement in the PVR at 6 months vs. tamsulosin. With respect to the secondary efficacy variables, the mean changes in the IPSS voiding score at 1 month in the naftopidil, tamsulosin, and silodosin groups were +6.5, +5.6, and +4.5, respectively; silodosin showed a significant improvement in the IPSS voiding score at 1 month vs. naftopidil. Conclusions: Silodosin has a greater impact on improving PI

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

    SciTech Connect

    Kittel, Jeffrey A.; Reddy, Chandana A.; Smith, Kristin L.; Stephans, Kevin L.; Tendulkar, Rahul D.; Ulchaker, James; Angermeier, Kenneth; Campbell, Steven; Stephenson, Andrew; Klein, Eric A.; Wilkinson, D. Allan; Ciezki, Jay P.

    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.

  12. Intracellular Localization of Lipoxygenases-1 and -2 in Germinating Soybean Seeds by Indirect Labeling with Protein A-Colloidal Gold Complexes

    PubMed Central

    Vernooy-Gerritsen, Marjan; Leunissen, Jan L. M.; Veldink, Gerrit A.; Vliegenthart, Johannes F. G.

    1984-01-01

    Soybean lipoxygenases-1 and -2 were localized intracellularly in seeds at various stages of germination by indirect labeling of cryosections with protein A-colloidal gold complexes. Two sizes of gold particles (Au5 and Au16) were used in single- and double-labeling experiments. In primary leaves, lipoxygenases are demonstrated to occur in vacuolating parenchyma cells but not in massive, nondifferentiated cells. In cotyledons, both isoenzymes are localized in the cytoplasm of storage parenchyma cells and in an aberrant type of protein bodies, occurring in hypodermis and vascular bundle sheath cells. No association has been found with either protein bodies in storage parenchyma cells or lipid bodies, mitochondria, and other organelles in any type of cell. The possible significance of lipoxygenase in the metabolism of storage lipids and its possible function as a regulatory enzyme are discussed on the basis of the random distribution throughout the cytoplasm of storage parenchyma cells and the course of biochemical processes during seed germination. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 Fig. 6 PMID:16663951

  13. [Receptor-mediated endocytosis in the cells of cold-blooded animals. II. The fate of internalized 125I-insulin in the isolated hepatocytes of the lamprey and the frog].

    PubMed

    Lappova, Iu L; Leĭbush, B N

    1994-01-01

    The 125I-insulin outflow from isolated hepatocytes of the frog and lamprey "loaded" with the labeled hormone has been studied. It is shown that the ligand outflow from the frog cells increased with the increase in the incubation temperature from 0 up to 20 degrees C. The curves of the rest cell radioactivity were reciprocal to those of the radioactivity accumulated in the medium at the corresponding temperatures. At 0.5 and 20 degrees C the degraded 125I-insulin made 5.7 and 17% of the whole hormone accumulated in the medium. In the lamprey hepatocytes, neither accumulation in the incubation medium nor outflow of the radioactivity from cell was seen at all temperatures studied. The intracellular degradation of 125I-insulin in the frog hepatocytes was no more than 7% of the internalized ligand, compared to about 25% in the lamprey cells. The specific binding of 125I-insulin was twice increased in the presence of lysosomal inhibitor chloroquin; contrary to this, no increase was found in the lamprey hepatocytes. The results of experiments on the frog hepatocytes lead us to a conclusion that the processing pathway of internalized insulin in cold-blooded vertebrate cells is similar mainly to that in cells of warm-blooded species, but takes place at lower temperatures and with slower rates. The peculiarities of processing in the lamprey hepatocytes (extralysosomal ligand degradation, the inability to release the internalized ligand and its degradation products) are dependent on a deep transformation of hepatocytes during prespawning migration period. PMID:7701627

  14. Seed coat color and seed weight contribute differential responses of targeted metabolites in soybean seeds.

    PubMed

    Lee, Jinwook; Hwang, Young-Sun; Kim, Sun Tae; Yoon, Won-Byong; Han, Won Young; Kang, In-Kyu; Choung, Myoung-Gun

    2017-01-01

    The distribution and variation of targeted metabolites in soybean seeds are affected by genetic and environmental factors. In this study, we used 192 soybean germplasm accessions collected from two provinces of Korea to elucidate the effects of seed coat color and seeds dry weight on the metabolic variation and responses of targeted metabolites. The effects of seed coat color and seeds dry weight were present in sucrose, total oligosaccharides, total carbohydrates and all measured fatty acids. The targeted metabolites were clustered within three groups. These metabolites were not only differently related to seeds dry weight, but also responded differentially to seed coat color. The inter-relationship between the targeted metabolites was highly present in the result of correlation analysis. Overall, results revealed that the targeted metabolites were diverged in relation to seed coat color and seeds dry weight within locally collected soybean seed germplasm accessions. PMID:27507473

  15. Evaluation of the Coat-A-Count sup 125 I fentanyl RIA: Comparison of sup 12 5I RIA and GC/MS-SIM for quantification of fentanyl in case urine specimens

    SciTech Connect

    Watts, V.W.; Caplan, Y.H. )

    1990-09-01

    The Coat-A-Count solid phase {sup 125}I 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 {sup 125}I 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 {sup 125}I RIA was compared to GC/MS quantifications of fentanyl in 35 positive and 20 negative case urine specimens.

  16. Dosimetric and radiobiological comparison of volumetric modulated arc therapy, high-dose rate brachytherapy, and low-dose rate permanent seeds implant for localized prostate cancer.

    PubMed

    Yang, Ruijie; Zhao, Nan; Liao, Anyan; Wang, Hao; Qu, Ang

    2016-01-01

    To investigate the dosimetric and radiobiological differences among volumetric modulated arc therapy (VMAT), high-dose rate (HDR) brachytherapy, and low-dose rate (LDR) permanent seeds implant for localized prostate cancer. A total of 10 patients with localized prostate cancer were selected for this study. VMAT, HDR brachytherapy, and LDR permanent seeds implant plans were created for each patient. For VMAT, planning target volume (PTV) was defined as the clinical target volume plus a margin of 5mm. Rectum, bladder, urethra, and femoral heads were considered as organs at risk. A 78Gy in 39 fractions were prescribed for PTV. For HDR and LDR plans, the dose prescription was D90 of 34Gy in 8.5Gy per fraction, and 145Gy to clinical target volume, respectively. The dose and dose volume parameters were evaluated for target, organs at risk, and normal tissue. Physical dose was converted to dose based on 2-Gy fractions (equivalent dose in 2Gy per fraction, EQD2) for comparison of 3 techniques. HDR and LDR significantly reduced the dose to rectum and bladder compared with VMAT. The Dmean (EQD2) of rectum decreased 22.36Gy in HDR and 17.01Gy in LDR from 30.24Gy in VMAT, respectively. The Dmean (EQD2) of bladder decreased 6.91Gy in HDR and 2.53Gy in LDR from 13.46Gy in VMAT. For the femoral heads and normal tissue, the mean doses were also significantly reduced in both HDR and LDR compared with VMAT. For the urethra, the mean dose (EQD2) was 80.26, 70.23, and 104.91Gy in VMAT, HDR, and LDR brachytherapy, respectively. For localized prostate cancer, both HDR and LDR brachytherapy were clearly superior in the sparing of rectum, bladder, femoral heads, and normal tissue compared with VMAT. HDR provided the advantage in sparing of urethra compared with VMAT and LDR.

  17. Local tissue destruction and procoagulation properties of Echis carinatus venom: inhibition by Vitis vinifera seed methanol extract.

    PubMed

    Mahadeswaraswamy, Y H; Nagaraju, S; Girish, K S; Kemparaju, K

    2008-07-01

    Plant extracts are extensively used against snakebites in Indian folk medicine. In this study, one such traditionally used plant, Vitis vinifera L. (Vitaceae) seed methanol extract has been studied for its ability to neutralize Indian Echis carinatus (saw-scaled viper) venom. The extract effectively inhibited toxic effects, such as oedema, haemorrhage, myonecrosis and coagulation of citrated human plasma. Further, the extract inhibited the caseinolytic, hyaluronolytic and fibrinogenolytic activities of the venom. The extract caused dose dependent inhibition of the toxic activities studied, suggesting venom inhibition. Thus, the anti-snake venom property of the extract appears to be highly promising for further investigation in order to achieve better neutralization of Indian E. carinatus venom poisoning.

  18. Local tissue destruction and procoagulation properties of Echis carinatus venom: inhibition by Vitis vinifera seed methanol extract.

    PubMed

    Mahadeswaraswamy, Y H; Nagaraju, S; Girish, K S; Kemparaju, K

    2008-07-01

    Plant extracts are extensively used against snakebites in Indian folk medicine. In this study, one such traditionally used plant, Vitis vinifera L. (Vitaceae) seed methanol extract has been studied for its ability to neutralize Indian Echis carinatus (saw-scaled viper) venom. The extract effectively inhibited toxic effects, such as oedema, haemorrhage, myonecrosis and coagulation of citrated human plasma. Further, the extract inhibited the caseinolytic, hyaluronolytic and fibrinogenolytic activities of the venom. The extract caused dose dependent inhibition of the toxic activities studied, suggesting venom inhibition. Thus, the anti-snake venom property of the extract appears to be highly promising for further investigation in order to achieve better neutralization of Indian E. carinatus venom poisoning. PMID:18567054

  19. Autoradiographic localization of peptide YY and neuropeptide Y binding sites in the medulla oblongata

    SciTech Connect

    Leslie, R.A.; McDonald, T.J.; Robertson, H.A.

    1988-09-01

    Peptide YY is a highly potent emetic when given intravenously in dogs. We hypothesized that the area postrema, a small brain stem nucleus that acts as a chemoreceptive trigger zone for vomiting and lies outside the blood-brain barrier, might have receptors that PYY would bind to, in order to mediate the emetic response. We prepared (/sup 125/I)PYY and used autoradiography to show that high affinity binding sites for this ligand were highly localized in the area postrema and related nuclei of the dog medulla oblongata. Furthermore, the distribution of (/sup 125/I)PYY binding sites in the rat medulla oblongata was very similar to that in the dog; the distribution of (/sup 125/I)PYY binding sites throughout the rat brain was seen to be similar to the distribution of (/sup 125/I)NPY binding sites.

  20. Chemical Composition, Antibacterial and Phytotoxic Activities of Peganum harmala Seed Essential Oils from Five Different Localities in Northern Africa.

    PubMed

    Apostolico, Ida; Aliberti, Luigi; Caputo, Lucia; De Feo, Vincenzo; Fratianni, Florinda; Nazzaro, Filomena; Souza, Lucèia Fàtima; Khadhr, Maroua

    2016-01-01

    Peganum harmala L., also known as Syrian rue or Pègano, is a herbaceous plant belonging to the Zygohpyllaceae family, and is widely used in traditional medicine. The chemical composition of essential oils of P. harmala seeds from five different regions of Northern Africa (Algeria, Egypt, Libya, Morocco and Tunisia) was studied by GC and GC-MS analyses. A total of 105 compounds were identified, the main components being oxygenated monoterpenes and oxygenated sesquiterpenes. Eugenol is the main component in all oils. The antimicrobial activity of the essential oils was assayed against some bacterial strains: Staphylococcus aureus (DSM 25693), Bacillus cereus (DSM 4313), Bacillus cereus (DSM4384), Escherichia coli (DMS 857) and Pseudomonas aeruginosa (ATCC 50071). All the oils showed different inhibitory activity. In the twentieth century this is an important result; we need possible new botanical drugs because the problem of resistance to antimicrobial drugs has become apparent. Moreover, the essential oils were evaluated for their possible in vitro phytotoxic activity against germination and initial radicle growth of Raphanus sativus L., Lepidium sativum L., and Ruta graveolens L. The results showed that both germination and radical elongation were sensitive to the oils. PMID:27649128

  1. Chemical Composition, Antibacterial and Phytotoxic Activities of Peganum harmala Seed Essential Oils from Five Different Localities in Northern Africa.

    PubMed

    Apostolico, Ida; Aliberti, Luigi; Caputo, Lucia; De Feo, Vincenzo; Fratianni, Florinda; Nazzaro, Filomena; Souza, Lucèia Fàtima; Khadhr, Maroua

    2016-09-15

    Peganum harmala L., also known as Syrian rue or Pègano, is a herbaceous plant belonging to the Zygohpyllaceae family, and is widely used in traditional medicine. The chemical composition of essential oils of P. harmala seeds from five different regions of Northern Africa (Algeria, Egypt, Libya, Morocco and Tunisia) was studied by GC and GC-MS analyses. A total of 105 compounds were identified, the main components being oxygenated monoterpenes and oxygenated sesquiterpenes. Eugenol is the main component in all oils. The antimicrobial activity of the essential oils was assayed against some bacterial strains: Staphylococcus aureus (DSM 25693), Bacillus cereus (DSM 4313), Bacillus cereus (DSM4384), Escherichia coli (DMS 857) and Pseudomonas aeruginosa (ATCC 50071). All the oils showed different inhibitory activity. In the twentieth century this is an important result; we need possible new botanical drugs because the problem of resistance to antimicrobial drugs has become apparent. Moreover, the essential oils were evaluated for their possible in vitro phytotoxic activity against germination and initial radicle growth of Raphanus sativus L., Lepidium sativum L., and Ruta graveolens L. The results showed that both germination and radical elongation were sensitive to the oils.

  2. AtNHX5 and AtNHX6 Are Required for the Subcellular Localization of the SNARE Complex That Mediates the Trafficking of Seed Storage Proteins in Arabidopsis

    PubMed Central

    Wu, Xuexia; Ebine, Kazuo; Ueda, Takashi; Qiu, Quan-Sheng

    2016-01-01

    The SNARE complex composed of VAMP727, SYP22, VTI11 and SYP51 is critical for protein trafficking and PSV biogenesis in Arabidopsis. This SNARE complex directs the fusion between the prevacuolar compartment (PVC) and the vacuole, and thus mediates protein trafficking to the vacuole. In this study, we examined the role of AtNHX5 and AtNHX6 in regulating this SNARE complex and its function in protein trafficking. We found that AtNHX5 and AtNHX6 were required for seed production, protein trafficking and PSV biogenesis. We further found that the nhx5 nhx6 syp22 triple mutant showed severe defects in seedling growth and seed development. The triple mutant had short siliques and reduced seed sets, but larger seeds. In addition, the triple mutant had numerous smaller protein storage vacuoles (PSVs) and accumulated precursors of the seed storage proteins in seeds. The PVC localization of SYP22 and VAMP727 was repressed in nhx5 nhx6, while a significant amount of SYP22 and VAMP727 was trapped in the Golgi or TGN in nhx5 nhx6. AtNHX5 and AtNHX6 were co-localized with SYP22 and VAMP727. Three conserved acidic residues, D164, E188, and D193 in AtNHX5 and D165, E189, and D194 in AtNHX6, were essential for the transport of the storage proteins, indicating the importance of exchange activity in protein transport. AtNHX5 or AtNHX6 did not interact physically with the SNARE complex. Taken together, AtNHX5 and AtNHX6 are required for the PVC localization of the SNARE complex and hence its function in protein transport. AtNHX5 and AtNHX6 may regulate the subcellular localization of the SNARE complex by their transport activity. PMID:26986836

  3. Single Mr approximately 103,000 /sup 125/I-beta-nerve growth factor-affinity-labeled species represents both the low and high affinity forms of the nerve growth factor receptor

    SciTech Connect

    Green, S.H.; Greene, L.A.

    1986-11-15

    Both high and low affinity receptors for nerve growth factor (NGF) have been described, but only the former appear to mediate NGF actions and uptake. To specifically characterize the molecular identity of the high affinity site and to compare it with the low affinity site, the water-soluble carbodiimide EDC was used to cross-link /sup 125/I-NGF to NGF receptors on: rat PC12 cells, PC12nnr5 cells (PC12 mutants that have only low affinity NGF binding), SH-SY5Y human neuroblastoma cells (which have only high affinity binding sites), and cultured rat sympathetic ganglion cells. A variety of criteria were used to distinguish the two classes of affinity-labeled receptors: competition with unlabeled NGF, dissociation rate, and selective solubilization by 0.1% Triton X-100. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis revealed that cross-linking generated only a single Mr approximately 103,000 /sup 125/I-NGF affinity-labeled species which represents both the low and high affinity forms of the receptor. The /sup 125/I-NGF X receptor complexes formed with both affinity classes of the receptor were quantitatively immunoprecipitated by the monoclonal anti-NGF-receptor antibody 192-IgG and both showed identical shifts in mobility when subjected to sodium dodecyl sulfate-polyacrylamide gel electrophoresis under nonreducing conditions. These findings indicate that both high and low affinity NGF receptors possess apparently identical NGF-binding moieties. The differences between the kinetic and functional properties of the two receptor types may therefore result from their interactions with other membrane components or with cytoplasmic proteins.

  4. Utility of radioisotopic filtration markers in chronic renal insufficiency: Simultaneous comparison of sup 125 I-iothalamate, sup 169 Yb-DTPA, sup 99m Tc-DTPA, and inulin. The Modification of Diet in Renal Disease Study

    SciTech Connect

    Perrone, R.D.; Steinman, T.I.; Beck, G.J.; Skibinski, C.I.; Royal, H.D.; Lawlor, M.; Hunsicker, L.G. )

    1990-09-01

    Assessment of glomerular filtration rate (GFR) with inulin is cumbersome and time-consuming. Radioisotopic filtration markers have been studied as filtration markers because they can be used without continuous intravenous (IV) infusion and because analysis is relatively simple. Although the clearances of 99mTc-DTPA, 169Yb-DTPA, and 125I-iothalamate have each been compared with inulin, rarely has the comparability of radioisotopic filtration markers been directly evaluated in the same subject. To this purpose, we determined the renal clearance of inulin administered by continuous infusion and the above radioisotopic filtration markers administered as bolus injections, simultaneously in four subjects with normal renal function and 16 subjects with renal insufficiency. Subjects were studied twice in order to assess within-study and between-study variability. Unlabeled iothalamate was infused during the second half of each study to assess its effect on clearances. We found that renal clearance of 125I-iothalamate and 169Yb-DTPA significantly exceeded clearance of inulin in patients with renal insufficiency, but only by several mL.min-1.1.73m-2. Overestimation of inulin clearance by radioisotopic filtration markers was found in all normal subjects. No differences between markers were found in the coefficient of variation of clearances either between periods on a given study day (within-day variability) or between the two study days (between-day variability). The true test variability between days did not correlate with within-test variability. We conclude that the renal clearance of 99mTc-DTPA, 169Yb-DTPA, or 125I-iothalamate administered as a single IV or subcutaneous injection can be used to accurately measure GFR in subjects with renal insufficiency; use of the single injection technique may overestimate GFR in normal subjects.

  5. Studies of the biogenic amine transporters. VII. Characterization of a novel cocaine binding site identified with [125I]RTI-55 in membranes prepared from human, monkey and guinea pig caudate.

    PubMed

    Rothman, R B; Silverthorn, M L; Glowa, J R; Matecka, D; Rice, K C; Carroll, F I; Partilla, J S; Uhl, G R; Vandenbergh, D J; Dersch, C M

    1998-04-01

    [125I]RTI-55 is a cocaine analog with high affinity for dopamine (DA) and serotonin (5-HT) transporters. Quantitative ligand binding studies revealed a novel high affinity [125I]RTI-55 binding site assayed under 5-HT transporter (SERT) conditions which has low affinity for almost all classic biogenic amine transporter ligands, including high affinity 5-HT transporter inhibitors such as paroxetine, but which retains high affinity for cocaine analogs. This site, termed SERT(site2) for its detection under 5-HT transporter conditions (not for an association with the SERT) occurs in monkey caudate, human caudate, and guinea pig caudate membranes, but not in rat caudate membranes. SERT(site2) is distinguished from the DA transporter (DAT) and SERT by several criteria, including a distinct ligand-selectivity profile, the inability to detect SERT(site2) in cells stably expressing the cloned human DAT, and insensitivity to irreversible ligands which inhibit [125I]RTI-55 binding to the DAT and SERT. Perhaps the most striking finding about SERT(site2) is that a wide range of representative antidepressant agents have very low affinity for SERT(site2). The affinity of cocaine for this site is not very different from the concentration cocaine achieves in the brain at pharmacological doses. Viewed collectively with the observation that ligands with high affinity for SERT(site2) are mostly cocaine analogs, these data lead us to speculate that actions of cocaine which differ from those of classic biogenic amine uptake inhibitors may be mediated in part via SERT(site2).

  6. In vivo SPECT and ex vivo autoradiographic brain imaging of the novel selective CB1 receptor antagonist radioligand [125I]SD7015 in CB1 knock-out and wildtype mouse

    PubMed Central

    Máthé, Domokos; Horváth, Ildikó; Szigeti, Krisztián; Donohue, Sean R.; Pike, Victor W.; Jia, Zisheng; Ledent, Catherine; Palkovits, Miklós; Freund, Tamás F.; Halldin, Christer; Gulyás, Balázs

    2014-01-01

    We aimed to evaluate the novel high-affinity and relatively lipophilic CB1 receptor (CB1R) antagonist radioligand [125I]SD7015 for SPECT imaging of CB1Rs in vivo using the multiplexed multipinhole dedicated small animal SPECT/CT system, NanoSPECT/CTPLUS (Mediso, Budapest, Hungary), in knock-out CB1 receptor knock-out (CB1R-/-) and wildtype mice. In order to exclude possible differences in cerebral blood flow between the two types of animals, HMPAO SPECT scans were performed, whereas in order to confirm the brain uptake differences of the radioligand between knock-out mice and wildtype mice, in vivo scans were complemented with ex vivo autoradiographic measurements using the brains of the same animals. With SPECT/CT imaging, we measured the brain uptake of radioactivity, using %SUV (% standardised uptake values) in CB1R-/- mice (n = 3) and C57BL6 wildtype mice (n = 7) under urethane anaesthesia after injecting [125I]SD7015 intravenously or intraperitoneally. The Brookhaven Laboratory mouse MRI atlas was fused to the SPECT/CT images by using a combination of rigid and non-rigid algorithms in the Mediso Fusion™ (Mediso, Budapest, Hungary) and VivoQuant (inviCRO, Boston, MA, USA) softwares. Phosphor imager plate autoradiography (ARG) was performed on 4 μm-thin cryostat sections of the excised brains. %SUV was 8.6 ± 3.6 (average ± SD) in CB1R-/- mice and 22.1 ± 12.4 in wildtype mice between 2 and 4 h after injection (p < 0.05). ARG of identically taken sections from wildtype mouse brain showed moderate radioactivity uptake when compared with the in vivo images, with a clear difference between grey matter and white matter, whereas ARG in CB1R(-/-) mice showed practically no radioactivity uptake. [125I]SD7015 enters the mouse brain in sufficient amount to enable SPECT imaging. Brain radioactivity distribution largely coincides with that of the known CB1R expression pattern in rodent brain. We conclude that [125I]SD7015 should be a useful SPECT radioligand for

  7. In vivo SPECT and ex vivo autoradiographic brain imaging of the novel selective CB1 receptor antagonist radioligand [125I]SD7015 in CB1 knock-out and wildtype mouse.

    PubMed

    Máthé, Domokos; Horváth, Ildikó; Szigeti, Krisztián; Donohue, Sean R; Pike, Victor W; Jia, Zisheng; Ledent, Catherine; Palkovits, Miklós; Freund, Tamás F; Halldin, Christer; Gulyás, Balázs

    2013-02-01

    We aimed to evaluate the novel high-affinity and relatively lipophilic CB(1) receptor (CB(1)R) antagonist radioligand [(125)I]SD7015 for SPECT imaging of CB(1)Rs in vivo using the multiplexed multipinhole dedicated small animal SPECT/CT system, NanoSPECT/CT(PLUS) (Mediso, Budapest, Hungary), in knock-out CB(1) receptor knock-out (CB(1)R-/-) and wildtype mice. In order to exclude possible differences in cerebral blood flow between the two types of animals, HMPAO SPECT scans were performed, whereas in order to confirm the brain uptake differences of the radioligand between knock-out mice and wildtype mice, in vivo scans were complemented with ex vivo autoradiographic measurements using the brains of the same animals. With SPECT/CT imaging, we measured the brain uptake of radioactivity, using %SUV (% standardised uptake values) in CB(1)R-/- mice (n=3) and C57BL6 wildtype mice (n=7) under urethane anaesthesia after injecting [(125)I]SD7015 intravenously or intraperitoneally. The Brookhaven Laboratory mouse MRI atlas was fused to the SPECT/CT images by using a combination of rigid and non-rigid algorithms in the Mediso Fusion™ (Mediso, Budapest, Hungary) and VivoQuant (inviCRO, Boston, MA, USA) softwares. Phosphor imager plate autoradiography (ARG) was performed on 4 μm-thin cryostat sections of the excised brains. %SUV was 8.6±3.6 (average±SD) in CB(1)R-/- mice and 22.1±12.4 in wildtype mice between 2 and 4 h after injection (p<0.05). ARG of identically taken sections from wildtype mouse brain showed moderate radioactivity uptake when compared with the in vivo images, with a clear difference between grey matter and white matter, whereas ARG in CB(1)R(-/-) mice showed practically no radioactivity uptake. [(125)I]SD7015 enters the mouse brain in sufficient amount to enable SPECT imaging. Brain radioactivity distribution largely coincides with that of the known CB(1)R expression pattern in rodent brain. We conclude that [(125)I]SD7015 should be a useful SPECT

  8. Detection of metabolic activity by [125I]-Iododeoxyuridine incorporation into DNA in Colwellia psychrerythraea over a temperature range from 8 °C to -40 °C

    NASA Astrophysics Data System (ADS)

    Summers, David; Diaz-Maldonado, Hector; Duart-Garcia, Carolina; Karouia, Fathi; Santos, Orlando; Trent, Jonathan

    A central issue of interest for microbial ecology as well as Astrobiology is; "what are the environmental limits of microbial metabolic activity"? This question is crucial to such issues as where life might be found in the solar system, where life might found in extreme environments on the Earth, and how life may have survived and evolved through difficult periods. For example, the last refuges of life on the surface of Mars may well have been environments where temperatures were such that organisms had metabolisms too low to allow them to repair damage caused by background radiation. Understanding how long organisms can persist in state of near-senescence, imposed either by depressed temperatures or starvation, is necessary to comprehend how a biosphere can survive climate cycles. One of the limiting factors in the survival of "dormant" organisms is difficulty in repairing damage to various large molecules such as DNA. Recent work has shown that microbes are not metabolically inactive below the freezing point of water. This raises the questions of what damage can be repaired in these "dormant" states. We present results where we use the incorporation of 125 I-deoxyuridine into the DNA to measure microbial metabolic activity at low temperature. Since an organic iodo group is close to the same as a methyl group, the compound 125 I-deoxyuridine can act as analog for thymidine, becoming incorporated into DNA during repair and/or synthesis. Furthermore, the high activity of 125 I, and the ability of multiphoton detection (MPD) to detect levels below background levels, allow higher sensitivity than is normally possible. Therefore, we present work where the incorporation 125 I-deoxyuridine into the DNA of Colwellia psychrerythraea has been studied over a temperature range from 8 ° C to -40 ° C. These results show that DNA repair and/or synthesis can occur below 0 ° C. More generally, this method can enablethe detection of metabolic activity to lower levels than

  9. Calibration procedures for seeds preloaded in cartridges

    SciTech Connect

    Brame, Ryan S.; Cohen, Gil'ad N.; Zaider, Marco

    2006-08-15

    Radioactive seeds preloaded in sterilized cartridges or needles are commonly obtainable from manufacturers. Under the US regulations for control of radioactive materials, seed users are required to account for all seeds and independently verify their air kerma strength (S{sub K}). As a result, the viability of inspection schemes that rely on measurement of aggregate seeds is of interest. In this paper we consider the conditions (if any) under which cartridge inspection can satisfy regulatory requirements and still provide practical benefit (i.e., time savings) against the regular single-seed assay. The standards for comparison are the recommendations of AAPM TG40, AAPM TG56, and ACR's 'Standard for the Performance of Manually Loaded Brachytherapy Sources'. The practical benefit is judged in comparison to the effort required to apply the 10% assay recommendation of TG40 to seeds in cartridges. Two specific cartridge inspection schemes are considered: (a) measuring the S{sub K} of each cartridge in a batch; (b) measuring a single cartridge sampled at random from the batch. Unlike the 10% assay, which is defined (imperfectly, in our view) without reference to the prevalence of in-calibration seeds, the estimation of the relative merits of cartridge inspection methods must necessarily include such information and, as such, is manufacturer specific. In this paper results are provided for Oncura model 6711 {sup 125}I seeds in shielded and unshielded Mick cartridges. We show that the only practically useful cartridge inspection scheme is the batch scheme applied to unshielded cartridges. The false positive rates associated with the other schemes are such that we expect to open a cartridge (and perform the 10% assay) at least 80% of the time. While anything less than 100% of the time is theoretically an improvement, this neglects the additional effort required to assay the cartridges.

  10. Excretion of radionuclides in human breast milk following administration of /sup 125/I-fibrinogen, /sup 99/Tc/sup m/-MAA and /sup 51/Cr-EDTA

    SciTech Connect

    Mattsson, S.; Johansson, L.; Nosslin, B.; Ahlgren, L.

    1981-06-01

    Very few biokinetic and dosimetric data for estimating the absorbed dose to a breast-feeding child are available in the literature. The few available are usually case reports. We have measured the activity concentration in breast milk from one patient after administration of /sup 125/I-fibrinogen, from two patients after administration of /sup 99/Tc/sup m/-macroaggregated albumin, and from one patient after administration of /sup 51/Cr-EDTA. We have compared our data with earlier published results and estimated the absorbed dose to the breast-feeding child using biokinetic data presented in this work and recently published S-values for new-born children.

  11. Photoaffinity labeling of opiate (enkephalin) receptor of rat brain plasma membranes with /sup 125/I(D-Ala/sup 2/, p-N/sub 3/-Phe/sup 4/-Met/sup 5/)-enkephalin

    SciTech Connect

    Yeung, C.W.T.

    1986-05-01

    A photoreactive (D-Ala/sup 2/, p-N/sub 3/-Phe/sup 4/-Met/sup 5/)enkephalin derivative was prepared, iodinated with carrier free /sup 125/I and then purified by high performance liquid chromatography. The purified radioactive photoprobe was monoiodinated at the amino terminal tyrosine residue. This radioactive photoprobe was used to photoaffinity label plasma membranes prepared from rat brain, spinal cord and cerebellum. The photolabeled plasma membranes were analyzed by sodium dodecyl sulfate gel electrophoresis. A 46,000-daltons band was specifically photolabeled in the plasma membranes of brain and spinal cord but not in the plasma membranes from cerebellum. The photolabeling of this band was inhibited by peptides related to enkephalin by not but substance P or gastrin tetrapeptide. These data demonstrate that the labeled 46,000-daltons band is a protein of the opiate (enkephalin)receptor.

  12. Comparison of /sup 125/I-labeled and /sup 14/C-Labeled peptides of the major outer membrane protein of Chlamydia Trachomatis Strain L2/434 separated by high-performance liquid chromatography

    SciTech Connect

    Judd, R.C.; Caldwell, H.D.

    1985-01-01

    The objective of this study was to determine if in-gel chloramine-T radioiodination adequately labels OM proteins to allow for accurate and precise structural comparison of these molecules. Therefore, intrinsically /sup 14/C-amino acid labeled proteins and /sup 125/I-labeled proteins were cleaved with two endopeptidic reagents and the peptide fragments separated by HPLC. A comparison of retention times of the fragments, as determined by differential radiation counting, thus indicated whether /sup 125/Ilabeling identified of all the peptide peaks seen in the /sup 14/Clabeled proteins. Results demonstrated that radioiodination yields complete and accurate information about the primary structure of outer membrane proteins. In addition, it permits the use of extremely small amounts of protein allowing for method optimization and multiple separations to insure reproducibility.

  13. Design and dosimetric considerations of a modified COMS plaque: The reusable 'seed-guide' insert

    SciTech Connect

    Astrahan, Melvin A.; Szechter, Andrzej; Finger, Paul T.

    2005-08-15

    The Collaborative Ocular Melanoma Study (COMS) developed a standardized set of eye plaques that consist of a 0.5 mm thick bowl-like gold alloy backing with a cylindrical collimating lip. A Silastic seed carrier into which {sup 125}I seeds are loaded was designed to fit within the backing. The carrier provides a standardized seed pattern and functions to offset the seeds by 1.0 mm from the concave (front) surface of the carrier. These Silastic carriers have been found to be difficult to load, preclude flash sterilization, and are a source of dosimetric uncertainty because the effective atomic number of Silastic is significantly higher than that of water. The main dosimetric effect of the Silastic carrier is a dose-reduction (compared to homogeneous water) of approximately 10%-15% for {sup 125}I radiation. The dose reduction is expected to be even greater for {sup 103}Pd radiation. In an attempt to improve upon, yet retain as much of the familiar COMS design as possible, we have developed a thin 'seed-guide' insert made of gold alloy. This new insert has cutouts which match the seed pattern of the Silastic carrier, but allows the seeds to be glued directly to the inner surface of the gold backing using either dental acrylic or a cyanoacrylate adhesive. When glued directly to the gold backing the seeds are offset a few tenths of a millimeter further away from the scleral surface compared to using the Silastic carrier. From a dosimetric perspective, the space formerly occupied by the Silastic carrier is now assumed to be water equivalent. Water equivalency is a desirable attribute for this space because it eliminates the dosimetric uncertainties related to the atomic composition of Silastic and thereby facilitates the use of either {sup 125}I and/or {sup 103}Pd seeds. The caveat is that a new source of dosimetric uncertainty would be introduced were an air bubble to become trapped in this space during or after the surgical insertion. The presence of air in this space

  14. Percutaneous implantation of (125)iodine seeds for treatment of portal vein tumor thrombosis in hepatocellular carcinoma.

    PubMed

    Liu, Yan; Liu, Ruibao; Wang, Ping; Li, Shijie; Shen, Haiyang

    2015-08-01

    The aim of the study is to evaluate the practicability and therapeutic efficacy of (125)iodine seeds implantation percutaneously for portal vein tumor thrombosis (PVTT) in patients with hepatocellular carcinoma (HCC). Nineteen patients with HCC accompanied with PVTT received ultrasound-guided implantation of 8-30 (125)iodine seeds, 8 mm apart within the portal vein tumor thrombi. The patients were followed up postoperatively for a period of 3-22 months. The successful rates of the procedure, postoperative changes of liver and renal function, hemogram, complications and therapeutic response were monitored. (125)I seeds were successfully implanted in the portal veins in all patients without serious complications. During the follow-up period, the portal vein tumor thrombi all shrunk obviously. Percutaneous implantation of (125)iodine seeds into the portal vein is an effective and safe treatment for PVTT accompanying HCC.

  15. Nutrient content of Prosopis africana seeds.

    PubMed

    Barminas, J T; Maina, H M; Ali, J

    1998-01-01

    The proximate and mineral compositions of Prosopis africana seeds used in the preparation of a local condiment in Nigeria and as animal feed were investigated. The proximate analysis showed that protein, ash and fiber values were comparable to Parkia africana seeds. However, the crude lipid content was lower than Parkia filicoidea seeds and decorticated groundnut. Phosphorus, potassium and calcium were the major mineral elements of the seeds, thereby suggesting that they could contribute partially to the overall daily intake of these elements.

  16. Distribution and binding of 18F-labeled and 125I-labeled analogues of ACI-80, a prospective molecular imaging biomarker of disease: a whole hemisphere post mortem autoradiography study in human brains obtained from Alzheimer's disease patients.

    PubMed

    Gulyás, Balázs; Spenger, Christian; Beliczai, Zsuzsa; Gulya, Károly; Kása, Péter; Jahan, Mahabuba; Jia, Zhisheng; Weber, Urs; Pfeifer, Andrea; Muhs, Andreas; Willbold, Dieter; Halldin, Christer

    2012-01-01

    One of the major pathological landmarks of Alzheimer's disease and other neurodegenerative diseases is the presence of amyloid deposits in the brain. The early non-invasive visualization of amyloid is a major objective of recent diagnostic neuroimaging approaches, including positron emission tomography (PET), with an eye on follow-up of disease progression and/or therapy efficacy. The development of molecular imaging biomarkers with binding affinity to amyloid in the brain is therefore in the forefront of imaging biomarker and radiochemistry research. Recently, a dodecamer peptide (amino acid sequence=QSHYRHISPAQV; denominated D1 or ACI-80) was identified as a prospective ligand candidate, binding with high ex vivo affinity to L-Aβ-amyloid (K(d): 0.4 μM). In order to assess the ligand's capacity to visualize amyloid in Alzheimer's disease (AD), two (125)I labeled and three (18)F labeled analogues of the peptide were synthesized and tested in post mortem human autoradiography experiments using whole hemisphere brain slices obtained from deceased AD patients and age matched control subjects. The (18)F-labeled radioligands showed more promising visualization capacity of amyloid that the (125)I-labeled radioligands. In the case of each (18)F radioligands the grey matter uptake in the AD brains was significantly higher than that in control brains. Furthermore, the grey matter: white matter uptake ratio was over ~2, the difference being significant for each (18)F-radioligands. The regional distribution of the uptake of the various radioligands systematically shows a congruent pattern between the high uptake regions and spots in the autoradiographic images and the disease specific signals obtained in adjacent or identical brain slices labeled with histological, immunohistochemical or autoradiographic stains for amyloid deposits or activated astrocytes. The present data, using post mortem human brain autoradiography in whole hemisphere human brains obtained from deceased

  17. [Incidence of postoperative deep vein thrombosis in general surgical and urological patients an investigation by means of the 125I-Fibrinogen test in 95 patients withoug prophylaxis (author's transl)].

    PubMed

    Schaub, N; Duckert, F; Fridrich, R; Gruber, U F

    1975-10-24

    We present the results of a control group of 95 patients who were thoroughly investigated in a prospective, randomized study, where the efficacy of small doses of s.c. heparin and dextran 40 is checked. The 125I-fibrogen test was used in all patients. 1. 35.8% of the patients develop deep vein thrombosis (DVT) during the first post-operative week. More than half of them show bilateral thrombosis. 2. There is no statistically significant difference in the thrombosis incidence between males and females. 3. 47% of the patients over 60 years develop postoperative DVT. Among those younger than 60 years, only 23% have DVT (P less than 0.025). 4. The DVT incidence in surgery of the colon is 58.3%. 5. Surgery for a malignant disease means probably increased risk for DVT (P less than 0.025). 6. More than half of the patients having a previous history of varicose veins develop postoperative DVT (P less than 0.025). 7. Obese patients are statistically seen not more prone to develop DVT than those of normal body build. 8. Immediately after operation 32.4% of DVT are diagnosed, 24 hrs. later 61.8%. 94% of all DVT are diagnosed up to the third postoperative day. 9. With the exeption of one patient, all DVT develop in the calf veins, 3/4 of all abnormal values were measured in the midcalf region.

  18. Effect of immunomodulation on the fate of tumor cells in the central nervous system and systemic organs of mice. Distribution of (/sup 125/I)5-iodo-2'-deoxyuridine-labeled KHT tumor cells after left intracardial injection

    SciTech Connect

    Conley, F.K.

    1982-08-01

    The effect of systemic immunomodulation on tumor cell arrest and retention in the central nervous system was studied by following radioactively labeled tumor cells. KHT mouse sarcoma tumor cells were labeled in vitro with (/sup 125/I)IdUrd, and 1x10/sup 5/ tumor cells were injected into the left side of the hearts of syngeneic C3H mice. Experimental groups consisted of untreated normal mice, mice pretreated iv with Corynebacterium parvum, and mice chronically infected with Toxoplasma gondii; in this model both groups of immunomodulated mice are protected from developing systemic metastatic tumor, but only Toxoplasma-infected mice have protection against metastatic brain tumor. At time intervals from 1 to 96 hours, groups of mice from each experimental group were killed, and the brain and other organs were monitored for radioactivity to determine the number of viable tumor cells that had been present at the time of death. Normal mice demonstrated significant retention of tumor cells in the brain and kidneys plus adrenals at 96 hours. By contrast, in both groups of immunomodulated mice tumor cells were rapidly eliminated from systemic organs, but tumor cells were significantly retained in the central nervous system even at 96 hours after tumor cell injections. The results indicated that generalized immunomodulation had more effect in elimination of tumor cells from systemic organs than from the brain and that the elimination of tumor cells from the brain in Toxoplasma-infected mice was a delayed phenomenon.

  19. Characterization and localization of atypical beta-adrenoceptors in rat ileum.

    PubMed Central

    Roberts, S. J.; Russell, F. D.; Molenaar, P.; Summers, R. J.

    1995-01-01

    1. Homogenate binding studies and receptor autoradiography have been used to examine the binding characteristics and localization of propranolol-resistant (-)-[125I]-cyanopindolol (CYP) binding sites in rat ileum. 2. Saturation studies with (-)-[125I]-CYP and homogenates of rat ileum identified a site with pKD 8.89 +/- 0.08 and Bmax = 50.3 +/- 4.1 fmol mg-1 protein (n = 6). Both beta 1- and beta 2-adrenoceptors (AR) were not detected in these preparations. 3. (-)-Isoprenaline infusion (400 micrograms kg-1 h-1) for 14 days caused no significant change in the density of (-)-[125I]-CYP binding which was 48.9 +/- 12.8 and 40.6 +/- 12.3 fmol mg-1 protein in control and isoprenaline-treated animals respectively (n = 6) (P = 0.97). 4. Competition for (-)-[125I]-CYP binding in the presence of 0.1 microM (-)-propranolol gave affinity values for CYP, tertatolol, alprenolol, ICI 118551 and CGP 20712A that correspond to known affinities at atypical beta-ARs. Stereoselectivity ratios for tertatolol and alprenolol were low. 5. Autoradiographic localization of propranolol resistant (-)-[125I]-CYP binding showed sites associated with the mucosa and to a lesser extent to the muscularis. A small population of beta 2-ARs were detected located predominantly in the longitudinal and circular smooth muscle layers. 6. This study identifies an (-)-[125I]-CYP binding site in rat ileum that is resistant to blockade by propranolol (0.1 microM), is located predominantly in the mucosa, shows resistance to downregulation by isoprenaline and has binding characteristics of the atypical beta-AR. Images Figure 6 PMID:8590969

  20. Labeling of insulin with non-radioactive 127I and application to incorporation of radioactive 125I for use in receptor-binding experiments by high-performance liquid chromatography.

    PubMed

    Rissler, K; Engelmann, P

    1996-04-26

    Conditions for the labeling of insulin with radioactive iodine isotopes were investigated by means of incorporation of non-radioactive 127I into the peptide. Either the chloramine-T (CT) or lactoperoxidase-hydrogen peroxide (LPO) technique was applied and reversed-phase high-performance liquid chromatography (RP-HPLC) was used for analysis of the reaction products. The LPO method provided the 127I-labeled peptide within 15-30 min, whereas the CT alternative yielded the labeled substrate even within 15 s. However, the latter reaction can only be controlled in a reproducible manner with difficulty and undesired side-reactions became increasingly prominent when the reaction time of 15 s was exceeded for only a few seconds. In another experiment, the LPO technique was applied for radiolabeling insulin with 125I. The product was first purified by size-exclusion chromatography (SEC) and then subjected to RP-HPLC. SEC yielded two peaks. The smaller one, which eluted at a slightly higher Kd value (accounting for about 14% of total radioactivity) predominantly consisted of material eluting at the column's void volume under the conditions of RP-HPLC, whereas the main SEC fraction (accounting for about 86% of total radioactivity) yielded a single peak, as shown by HPLC. The radioactive material attributable to the main SEC fraction revealed the expected receptor-binding properties, as evidenced by displacement experiments with non-radioactive insulin, as well as the action of tetradecanoyl phorbol acetate on the binding characteristics and thus indicating formation of a labeled hormone retaining biological activity.

  1. Classification of M/sub 1/ and M/sub 2/ receptor subtypes in vivo by autoradiography using (/sup 125/I) (R,R) 4IQNB: Implications for imaging receptor subtypes

    SciTech Connect

    Gibson, R.E.; Moody, T.; Kzeszotarski, W.J.; Schneidau, T.S.; Jagoda, E.M.; Reba, R.C.

    1985-05-01

    (/sup 125/I) (R,R) 3-Quinuclidinyl 4-Iodobenzilate (4IQNB) is a high affinity radiotracer for the muscarinic acetylcholine receptor which exhibits differential kinetics of dissociation from the receptor subtypes, M/sub 1/ and M/sub 2/. The authors have determined the relative percentages of M/sub 1/ to M/sub 2/-receptor subtype in six structures of rat brain by equilibrium competition using the selective antagonist, QNX, and by analysis of the off-rate profiles for 4IQNB. The results are comparable and provide: (% M/sub 1/) caudate nucleus - 100%, hippocampus - 92%, cortex - 82%, thalamus - 6%, superior + inferior colliculi - 41%, and pons - 23%. To determine the relative proportions of M/sub 1/ to M/sub 2/ receptors in vivo we examined the distribution of 4IQNB at 2 h and 24 h by autoradiography. At 2 h, both M/sub 1/ and M/sub 2/ receptors will be labeled but at 24 h only the M/sub 1/ receptor will retain radiotracer. At 2 h, all structures of the brain are variably labeled with the cortex, hippocampus, caudate nucleus, olfactory nuclei, nucleus accumbens, pontine nuclei, and anteroventral thalamic nucleus (AV) most heavily labeled. At 24 h, both the pontine and AV, as well as the less heavily labeled hypothalamus, superior colliculus and mesencephalic nuclei, are devoid of radiotracer thus indicating predominantly M/sub 2/ receptor. Quantitation is necessary to determine possible washout of activity from the M/sub 2/ receptors in cortex. Similar time studies in man should provide distinctions between the M/sub 1/ and M/sub 2/ receptor rich structures and the preferential loss of a subtype of receptor due to disease.

  2. Source strength assay of iodine-125 seeds sealed within sterile packaging.

    PubMed

    Otani, Yuki; Yamada, Takahiro; Kato, Shingo; Shikama, Naoto; Funakoshi, Kazuto; Kuroda, Isao; Numasaki, Hodaka; Nose, Takayuki; Dokiya, Takushi; Oguchi, Masahiko

    2013-01-01

    Early-stage prostate cancer is widely treated by iodine-125 (I-125) seed implantation. While quality assurance methods are in place to assure consistency in I-125 seed source strength, current methods involve the breaking of the sterilization package, raising issues concerning sterility and time limitations. The purpose of this study was to develop a method of characterizing the total source strength of I-125 seeds within a cartridge that has been sealed within a sterilization package and to evaluate the probability of detecting an out-of-calibration seed (aberrant seed). We defined a protocol to determine the ability of a well-type ionization chamber to detect aberrant I-125 seeds within a cartridge sealed in the sterilization package. A novel jig for a well-type ionization chamber was designed to accommodate the sterilization package. One seed was chosen randomly from two cartridges containing five or 15 seeds (0.544 U source strength) and was exchanged with aberrant seeds of six different source strengths. The source strength was measured at each position within the cartridge. The results indicated that the response of the well chamber was sensitive to changes in the aberrant seed position within the cartridge and the source strength of the aberrant seed. The correlation coefficient between single seed and batch assay results was high (0.998). A novel jig and a measurement method using a well ionization chamber were developed, which allowed for a batch assay characterization of the total source strength of I-125 seeds within a cartridge sealed within sterilization package. This method is simple, time-saving, and offers greater practical application. PMID:23470939

  3. Sequence, expression and tissue localization of a gene encoding a makorin RING zinc-finger protein in germinating rice (Oryza sativa L. ssp. Japonica) seeds.

    PubMed

    Arumugam, Thangavelu U; Davies, Eric; Morita, Eugene Hayato; Abe, Shunnosuke

    2007-01-01

    The makorin (MKRN) RING finger protein gene family encodes proteins (makorins) with a characteristic array of zinc-finger motifs and which are present in a wide array of eukaryotes. In the present study, we analyzed the structure and expression of a putative makorin RING finger protein gene in rice (Oryza sativa L. ssp. Japonica cv. Nipponbare). From the analysis of the genomic (AP003543), mRNA (AK120250) and deduced protein (BAD61603) sequences of the putative MKRN gene of rice, obtained from GenBank, we found that it was indeed a bona fide member of the MKRN gene family. The rice MKRN cDNA encoded a protein with four C3H zinc-finger-motifs, one putative Cys-His zinc-finger motif, and one RING zinc-finger motif. The presence of this distinct motif organization and overall amino acid identity clearly indicate that this gene is indeed a true MKRN ortholog. We isolated RNA from embryonic axes of rice seeds at various stages of imbibition and germination and studied the temporal expression profile of MKRN by RT-PCR. This analysis revealed that MKRN transcripts were present at all the time points studied. It was at very low levels in dry seeds, increased slowly during imbibition and germination, and slightly declined in the seedling growth stage. After 6days of germination, an organ-dependent expression pattern of MKRN was observed: highest in roots and moderate in leaves. Similarly to MKRN transcripts, transcripts of cytoskeletal actin and tubulin were also detected in dry embryos, steadily increased during imbibition and germination and leveled off after 24h of germination. We studied the spatial expression profile of MKRN in rice tissues, by using a relatively fast, simple and effective non-radioactive mRNA in situ hybridization (NRISH) technique, which provided the first spatial experimental data that hints at the function of a plant makorin. This analysis revealed that MKRN transcripts were expressed in young plumules, lateral root primordia, leaf primordia

  4. High affinity dopamine D2 receptor radioligands. 3. [[sup 123]I] and [[sup 125]I]epidepride: In vivo studies in rhesus monkey brain and comparison with in vitro pharmacokinetics in rat brain

    SciTech Connect

    Kessler, R.M.; Votaw, J.R.; Schmidt, D.E.; Ansari, M.S.; Holdeman, K.P.; Paulis, T. de; Clanton, J.A.; Pfeffer, R.; Manning, R.G.; Ebert, M.H. )

    1993-01-01

    Studies of [[sup 123]I]epidepride uptake in rhesus monkey brain were performed using single photon tomography. Striatal uptake peaked at 0.85% of administered dose/g at 107 min post-injection, then declined slowly to 0.70% of administered dose/g at 6 h. Striatal:posterior brain ratios rose from 2 at 25 min to 6.8 at 105 min, to 15 at 4 h and to 58 at 6.4 h. [[sup 123]I]Epidepride was displaced by haloperidol (0.1 and 1 mg/kg) with a half-life of washout of 55 min. Little displacement of [[sup 123]I]epidepride was observed following administration of 1 or 2 mg/kg d-amphetamine, respectively, indicating [[sup 123]I]epidepride is not easily displaced by endogenous dopamine. In vitro equilibrium binding studies with [[sup 125]I]epidepride using rat striatum revealed a K[sub D] of 46 pM and B[sub max] of 33 pmol/g tissue at 37[degrees]C, while at 25[degrees]C the K[sub D] was 25 pM and the B[sub max] 32 pmol/g tissue. In vitro kinetic analysis of association and dissociation curves revealed a half-life for receptor dissociation at 37[degrees]C of 15 min and 79--90 min at 25[degrees]C. Allowing for the temperature difference, there is good correspondence between in vivo and in vitro dissociation kinetics at 25[degrees]C. Increasing in vitro incubation temperature from 25 to 37[degrees]C caused a 6-fold increase in the dissociation rate, suggesting that there is a change in binding kinetics at the dopamine D2 receptor at 37[degrees]C compared to in vivo binding. The results of this study indicate that [[sup 123]I]epidepride is an excellent radioligand for SPECT studies of the dopamine D2 receptor in man. 34 refs., 4 figs.

  5. Hierarchical mechanisms of spatially contagious seed dispersal in complex seed-disperser networks.

    PubMed

    Fedriani, José M; Wiegand, Thorsten

    2014-02-01

    Intra- and interspecific spatially contagious seed dispersal has far-reaching implications for plant recruitment, distribution, and community assemblage. However, logistical and analytical limitations have curtailed our understanding concerning the mechanisms and resulting spatial patterns of contagious seed dispersal in most systems and, especially, in complex seed-disperser networks. We investigated mechanisms of seed aggregation using techniques of spatial point pattern analysis and extensive data sets on mutispecific endozoochorous seed rain generated by five frugivorous mammals in three Mediterranean shrublands over two seasons. Our novel analytical approach revealed three hierarchical and complementary mechanisms of seed aggregation acting at different levels (fecal samples, seeds, pairs of seed species) and spatial scales. First, the three local guilds of frugivores tended to deliver their feces highly aggregated at small and intermediate spatial scales, and the overall pattern of fecal delivery could be described well by a nested double-cluster Thomas process. Second, once the strong observed fecal aggregation was accounted for, the distribution of mammal feces containing seeds was clustered within the pattern of all feces (i.e., with and without seeds), and the density of fecal samples containing seeds was higher than expected around other feces containing seeds in two out of the three studied seed-disperser networks. Finally, at a finer level, mark correlation analyses revealed that for some plant species pairs, the number of dispersed seeds was positively associated either at small or large spatial scales. Despite the relatively invariant patterning of nested double-clustering, some attributes of endozoochorous seed rain (e.g., intensity, scales of aggregation) were variable among study sites due to changes in the ecological context in which seeds and their dispersers interact. Our investigation disentangles for the first time the hierarchy of synergic

  6. Through the Ring of Fire: Gamma-Ray Variability in Blazars by a Moving Plasmoid Passing a Local Source of Seed Photons

    NASA Astrophysics Data System (ADS)

    MacDonald, Nicholas R.; Marscher, Alan P.; Jorstad, Svetlana G.; Joshi, Manasvita

    2015-05-01

    Blazars exhibit flares across the electromagnetic spectrum. Many γ-ray flares are highly correlated with flares detected at optical wavelengths; however, a small subset appears to occur in isolation, with little or no variability detected at longer wavelengths. These “orphan” γ-ray flares challenge current models of blazar variability, most of which are unable to reproduce this type of behavior. We present numerical calculations of the time-variable emission of a blazar based on a proposal by Marscher et al. to explain such events. In this model, a plasmoid (“blob”) propagates relativistically along the spine of a blazar jet and passes through a synchrotron-emitting ring of electrons representing a shocked portion of the jet sheath. This ring supplies a source of seed photons that are inverse-Compton scattered by the electrons in the moving blob. The model includes the effects of radiative cooling, a spatially varying magnetic field, and acceleration of the blob's bulk velocity. Synthetic light curves produced by our model are compared to the observed light curves from an orphan flare that was coincident with the passage of a superluminal knot through the inner jet of the blazar PKS 1510-089. In addition, we present Very Long Baseline Array polarimetric observations that point to the existence of a jet sheath in PKS 1510-089, thus providing further observational support for the plausibility of our model. An estimate of the bolometric luminosity of the sheath within PKS 1510-089 is made, yielding {{L}sh}˜ 3× {{10}45} erg {{s}-1}. This indicates that the sheath within PKS 1510-089 is potentially a very important source of seed photons.

  7. LOCALIZATION OF POLYSOME-BOUND ALBUMIN AND SERINE DEHYDRATASE IN RAT LIVER CELL FRACTIONS

    PubMed Central

    Ikehara, Yukio; Pitot, Henry C.

    1973-01-01

    The polysomes involved in albumin and serine dehydratase synthesis were identified and localized by the binding to rat liver polysomes of anti-rat serum albumin and anti-serine dehydratase [125I]Fab dimer and monomer. Techniques were developed for the isolation of undegraded free and membrane-bound polysomes and for the preparation of [125I]Fab monomers and dimers from the IgG obtained from the antisera to the two proteins, rat serum albumin and serine dehydratase. The distribution of anti-rat serum albumin [125I]Fab dimer in the polysome profile is in accordance with the size of polysomes that are expected to be synthesizing albumin. By direct precipitation, it has been demonstrated that nascent chains isolated from the membrane-bound polysomes by puromycin were precipitated by anti-rat serum albumin-IgG at a level of 5–6 times those released from free polysomes. Anti-rat serum albumin-[125I]Fab dimer reacted with membrane-bound polysomes almost exclusively compared to the binding of nonimmune, control [125I]Fab dimer; a significant degree of binding of anti-rat serum albumin-[125I]Fab to free polysomes was also obtained. The [125I]Fab dimer made from normal control rabbit serum does not react with polysomes from liver at all and this preparation will not interact with polysomes extracted from tissues that do not synthesize rat serum albumin. Both anti-serine dehydratase-[125I]Fab monomer and dimer react with free and bound polysomes from livers of animals fed a chow diet or those fed a high 90% protein diet and given glucagon. In the latter instance, however, it is clear that the majority of the binding occurs to the bound polysomes. Furthermore, the specificity of this reaction may be further shown by the use of kidney polysomes that do not normally synthesize serine dehydratase. When these latter polysomes are isolated, even after the addition of crude and purified serine dehydratase, no reaction with anti-serine dehydratase-Fab fragments could be

  8. Seeding for pervasively overlapping communities

    NASA Astrophysics Data System (ADS)

    Lee, Conrad; Reid, Fergal; McDaid, Aaron; Hurley, Neil

    2011-06-01

    In some social and biological networks, the majority of nodes belong to multiple communities. It has recently been shown that a number of the algorithms specifically designed to detect overlapping communities do not perform well in such highly overlapping settings. Here, we consider one class of these algorithms, those which optimize a local fitness measure, typically by using a greedy heuristic to expand a seed into a community. We perform synthetic benchmarks which indicate that an appropriate seeding strategy becomes more important as the extent of community overlap increases. We find that distinct cliques provide the best seeds. We find further support for this seeding strategy with benchmarks on a Facebook network and the yeast interactome.

  9. Effects of rodent species, seed species, and predator cues on seed fate

    USGS Publications Warehouse

    Sivy, Kelly J.; Ostoja, Steven M.; Schupp, Eugene W.; Durham, Susan

    2011-01-01

    Seed selection, removal and subsequent management by granivorous animals is thought to be a complex interaction of factors including qualities of the seeds themselves (e.g., seed size, nutritional quality) and features of the local habitat (e.g. perceived predator risk). At the same time, differential seed selection and dispersal is thought to have profound effects on seed fate and potentially vegetation dynamics. In a feeding arena, we tested whether rodent species, seed species, and indirect and direct predation cues influence seed selection and handling behaviors (e.g., scatter hoarding versus larder hoarding) of two heteromyid rodents, Ord's kangaroo rat (Dipodomys ordii) and the Great Basin pocket mouse (Perognathus parvus). The indirect cue was shrub cover, a feature of the environment. Direct cues, presented individually, were (1) control, (2) coyote (Canis latrans) vocalization, (3) coyote scent, (4) red fox (Vulpes vulpes) scent, or (5) short-eared owl (Asio flammeus) vocalization. We offered seeds of three sizes: two native grasses, Indian ricegrass (Achnatherum hymenoides) and bluebunch wheatgrass (Pseudoroegneria spicata), and the non-native cereal rye (Secale cereale), each in separate trays. Kangaroo rats preferentially harvested Indian ricegrass while pocket mice predominately harvested Indian ricegrass and cereal rye. Pocket mice were more likely to scatter hoard preferred seeds, whereas kangaroo rats mostly consumed and/or larder hoarded preferred seeds. No predator cue significantly affected seed preferences. However, both species altered seed handling behavior in response to direct predation cues by leaving more seeds available in the seed pool, though they responded to different predator cues. If these results translate to natural dynamics on the landscape, the two rodents are expected to have different impacts on seed survival and plant recruitment via their different seed selection and seed handling behaviors.

  10. Effects of rodent species, seed species, and predator cues on seed fate

    NASA Astrophysics Data System (ADS)

    Sivy, Kelly J.; Ostoja, Steven M.; Schupp, Eugene W.; Durham, Susan

    2011-07-01

    Seed selection, removal and subsequent management by granivorous animals is thought to be a complex interaction of factors including qualities of the seeds themselves (e.g., seed size, nutritional quality) and features of the local habitat (e.g. perceived predator risk). At the same time, differential seed selection and dispersal is thought to have profound effects on seed fate and potentially vegetation dynamics. In a feeding arena, we tested whether rodent species, seed species, and indirect and direct predation cues influence seed selection and handling behaviors (e.g., scatter hoarding versus larder hoarding) of two heteromyid rodents, Ord's kangaroo rat ( Dipodomys ordii) and the Great Basin pocket mouse ( Perognathus parvus). The indirect cue was shrub cover, a feature of the environment. Direct cues, presented individually, were (1) control, (2) coyote ( Canis latrans) vocalization, (3) coyote scent, (4) red fox ( Vulpes vulpes) scent, or (5) short-eared owl ( Asio flammeus) vocalization. We offered seeds of three sizes: two native grasses, Indian ricegrass ( Achnatherum hymenoides) and bluebunch wheatgrass ( Pseudoroegneria spicata), and the non-native cereal rye ( Secale cereale), each in separate trays. Kangaroo rats preferentially harvested Indian ricegrass while pocket mice predominately harvested Indian ricegrass and cereal rye. Pocket mice were more likely to scatter hoard preferred seeds, whereas kangaroo rats mostly consumed and/or larder hoarded preferred seeds. No predator cue significantly affected seed preferences. However, both species altered seed handling behavior in response to direct predation cues by leaving more seeds available in the seed pool, though they responded to different predator cues. If these results translate to natural dynamics on the landscape, the two rodents are expected to have different impacts on seed survival and plant recruitment via their different seed selection and seed handling behaviors.

  11. Practical considerations for maximizing heat production in a novel thermobrachytherapy seed prototype

    SciTech Connect

    Gautam, Bhoj; Warrell, Gregory; Shvydka, Diana; Ishmael Parsai, E.; Subramanian, Manny

    2014-02-15

    Purpose: A combination of hyperthermia and radiation in the treatment of cancer has been proven to provide better tumor control than radiation administered as a monomodality, without an increase in complications or serious toxicities. Moreover, concurrent administration of hyperthermia and radiation displays synergistic enhancement, resulting in greater tumor cell killing than hyperthermia and radiation delivered separately. The authors have designed a new thermobrachytherapy (TB) seed, which serves as a source of both radiation and heat for concurrent brachytherapy and hyperthermia treatments when implanted in solid tumors. This innovative seed, similar in size and geometry to conventional seeds, will have self-regulating thermal properties. Methods: The new seed's geometry is based on the standard BEST Model 2301{sup 125}I seed, resulting in very similar dosimetric properties. The TB seed generates heat when placed in an oscillating magnetic field via induction heating of a ferromagnetic Ni–Cu alloy core that replaces the tungsten radiographic marker of the standard Model 2301. The alloy composition is selected to undergo a Curie transition near 50 °C, drastically decreasing power production at higher temperatures and providing for temperature self-regulation. Here, the authors present experimental studies of the magnetic properties of Ni–Cu alloy material, the visibility of TB seeds in radiographic imaging, and the ability of seed prototypes to uniformly heat tissue to a desirable temperature. Moreover, analyses are presented of magnetic shielding and thermal expansion of the TB seed, as well as matching of radiation dose to temperature distributions for a short interseed distance in a given treatment volume. Results: Annealing the Ni–Cu alloy has a significant effect on its magnetization properties, increasing the sharpness of the Curie transition. The TB seed preserves the radiographic properties of the BEST 2301 seed in both plain x rays and CT

  12. Local administration of monoclonal antibody-drug conjugate: a new strategy to reduce the local recurrence of colorectal cancer.

    PubMed

    Kitamura, K; Takahashi, T; Kotani, T; Miyagaki, T; Yamaoka, N; Tsurumi, H; Noguchi, A; Yamaguchi, T

    1992-11-15

    This report investigates the application of monoclonal antibody A7 and its drug conjugate in locally controlling colorectal cancer. The experimental protocol consisted of local retention, lymphatic delivery, normal organ distribution, systemic toxicity, and tumoricidal effects. When 125I-labeled monoclonal antibody (Mab) A7 was injected into the pelvis and the thigh of Balb/c mice, a high local retention unrelated to antigen-antibody interaction was observed at the injected site for 24 h after injection. An analysis of local retension properties related to antigen-antibody interaction, conducted by intratumorally or peritumorally injecting 125I-Mab A7 into the tumor-bearing athymic nude mice, revealed a significantly higher tumor localization of Mab A7 in comparison to i.v. injection. 125I-Mab A7 accumulated to a great extent in the ipsilateral regional lymph node but not in the contralateral regional lymph node. Normal organ accumulation of Mab A7 was lower in the locally injected group than in the i.v. injected group. Intratumoral injection of Mab A7-neocarzinostatin (A7-NCS) led to the complete remission of established tumor in 5 of 6 antigen-positive xenograft-bearing mice but exhibited a complete remission in only 1 of 6 antigen-negative xenograft-bearing mice. A single local injection of A7-NCS inhibited tumor development in 12 of 16 and 5 of 15 antigen-positive tumor-bearing mice and antigen-negative tumor-bearing mice, respectively, whereas neither a systemic injection of A7-NCS and NCS nor a local injection of NCS and saline had a notable inhibitory effect on tumor development. Systemic toxicity of NCS was markedly reduced when it was locally administered in the antibody-conjugated form. These findings indicate that local injection of immunoconjugate is a promising new field for controlling the local recurrence of colorectal cancer.

  13. Potential impact of prostate edema on the dosimetry of permanent seed implants using the new {sup 131}Cs (model CS-1) seeds

    SciTech Connect

    Chen Zhe; Deng Jun; Roberts, Kenneth; Nath, Ravinder

    2006-04-15

    Our aim in this work was to study the potential dosimetric effect of prostate edema on the accuracy of conventional pre- and post-implant dosimetry for prostate seed implants using the newly introduced {sup 131}Cs seed, whose radioactive decay half-life ({approx}9.7 days) is directly comparable to the average edema resolution half-life ({approx}10 days) observed previously by Waterman et al. for {sup 125}I implants [Int. J. Radiat. Oncol. Biol. Phys. 41, 1069-1077 (1998)]. A systematic calculation of the relative dosimetry effect of prostate edema on the {sup 131}Cs implant was performed by using an analytic solution obtained previously [Int. J. Radiat. Oncol. Biol. Phys. 47, 1405-1419 (2000)]. It was found that conventional preimplant dosimetry always overestimates the true delivered dose as it ignores the temporary increase of the interseed distance caused by edema. The overestimation for {sup 131}Cs implants ranged from 1.2% (for a small edema with a magnitude of 10% and a half-life of 2 days) to approximately 45% (for larger degree edema with a magnitude of 100% and a half-life of 25 days). The magnitude of pre- and post-implant dosimetry error for {sup 131}Cs implants was found to be similar to that of {sup 103}Pd implants for typical edema characteristics (magnitude <100%, and half-life <25 days); both of which are worse compared to {sup 125}I implants. The preimplant dosimetry error for {sup 131}Cs implants cannot be compensated effectively without knowing the edema characteristics before the seed implantation. On the other hand, the error resulted from a conventional post-implant dosimetry can be minimized (to within {+-}6%) for {sup 131}Cs implants if the post-implant dosimetry is performed at 10{+-}2 days post seed implantation. This 'optimum' post-implant dosimetry time is shorter than those determined previously for the {sup 103}Pd and {sup 125}I implants at 16{+-}4 days and 6{+-}1 weeks, respectively.

  14. Seed Treatment. Bulletin 760.

    ERIC Educational Resources Information Center

    Lowery, Harvey C.

    This manual gives a definition of seed treatment, the types of seeds normally treated, diseases and insects commonly associated with seeds, fungicides and insecticides used, types of equipment used for seed treatment, and information on labeling and coloring of treated seed, pesticide carriers, binders, stickers, and safety precautions. (BB)

  15. Development of receptors for insulin and insulin-like growth factor-I in head and brain of chick embryos: Autoradiographic localization

    SciTech Connect

    Bassas, L.; Girbau, M.; Lesniak, M.A.; Roth, J.; de Pablo, F. )

    1989-11-01

    In whole brain of chick embryos insulin receptors are highest at the end of embryonic development, while insulin-like growth factor-I (IGF-I) receptors dominate in the early stages. These studies provided evidence for developmental regulation of both types of receptors, but they did not provide information on possible differences between brain regions at each developmental stage or within one region at different embryonic ages. We have now localized the specific binding of (125I)insulin and (125I)IGF-I in sections of head and brain using autoradiography and computer-assisted densitometric analysis. Embryos have been studied from the latter part of organogenesis (days 6 and 12) through late development (day 18, i.e. 3 days before hatching), and the binding patterns have been compared with those in the adult brain. At all ages the binding of both ligands was to discrete anatomical regions. Interestingly, while in late embryos and adult brain the patterns of (125I)insulin and (125I) IGF-I binding were quite distinct, in young embryos both ligands showed very similar localization of binding. In young embryos the retina and lateral wall of the growing encephalic vesicles had the highest binding of both (125I)insulin and (125I)IGF-I. In older embryos, as in the adult brain, insulin binding was high in the paleostriatum augmentatum and molecular layer of the cerebellum, while IGF-I binding was prominent in the hippocampus and neostriatum. The mapping of receptors in a vertebrate embryo model from early prenatal development until adulthood predicts great overlap in any possible function of insulin and IGF-I in brain development, while it anticipates differential localized actions of the peptides in the mature brain.

  16. Urethra-Sparing, Intraoperative, Real-Time Planned, Permanent-Seed Prostate Brachytherapy: Toxicity Analysis

    SciTech Connect

    Zilli, Thomas; Taussky, Daniel; Donath, David; Le, Hoa Phong; Larouche, Renee-Xaviere; Beliveau-Nadeau, Dominique; Hervieux, Yannick; Delouya, Guila

    2011-11-15

    Purpose: To report the toxicity outcome in patients with localized prostate cancer undergoing {sup 125}I permanent-seed brachytherapy (BT) according to a urethra-sparing, intraoperative (IO), real-time planned conformal technique. Methods and Materials: Data were analyzed on 250 patients treated consecutively for low- or intermediate-risk prostate cancer between 2005 and 2009. The planned goal was urethral V{sub 150} = 0. Acute and late genitourinary (GU), gastrointestinal (GI), and erectile toxicities were scored with the International Prostate Symptom Score (IPSS) questionnaire and Common Terminology Criteria for Adverse Events (version 3.0). Median follow-up time for patients with at least 2 years of follow-up (n = 130) was 34.4 months (range, 24-56.9 months). Results: Mean IO urethra V{sub 150} was 0.018% {+-} 0.08%. Mean prostate D{sub 90} and V{sub 100} on day-30 computed tomography scan were 158.0 {+-} 27.0 Gy and 92.1% {+-} 7.2%, respectively. Mean IPSS peak was 9.5 {+-} 6.3 1 month after BT (mean difference from baseline IPSS, 5.3). No acute GI toxicity was observed in 86.8% of patients. The 3-year probability of Grade {>=}2 late GU toxicity-free survival was 77.4% {+-} 4.0%, with Grade 3 late GU toxicity encountered in only 3 patients. Three-year Grade 1 late GI toxicity-free survival was 86.1% {+-} 3.2%. No patient presented Grade {>=}2 late GI toxicity. Of patients with normal sexual status at baseline, 20.7% manifested Grade {>=}2 erectile dysfunction after BT. On multivariate analysis, elevated baseline IPSS (p = 0.016) and high-activity sources (median 0.61 mCi) (p = 0.033) predicted increased Grade {>=}2 late GU toxicity. Conclusions: Urethra-sparing IO BT results in low acute and late GU toxicity compared with the literature. High seed activity and elevated IPSS at baseline increased long-term GU toxicity.

  17. Effect of chia seed meal on baking quality of cakes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Chia seed is a good source of dietary fiber and complete proteins; chia seeds contain many health-promoting compounds and can be incorporated into baking goods for high-protein, high-fiber diet. Food grade chia seeds were obtained from a local grocery store and ground into meal using Retsch Model VD...

  18. S-SEED Simulator

    2008-11-21

    This code simulates the transient response of two self-electrooptic-effect devices (SEEDs) connected in series to form an S-SEED pair as used in all-optical high-speed switching. Both optical beam propagation and carrier motion is assumed to be normal to the epi plane, so the code is inherently 1D in nature. For each SEED, an optical input in W/cm**2 is specified as a function of time (usually a step function input). The signal is absorbed during amore » double pass through the intrinsic region, with a spatially-dependent absorption coefficient that is dependent on the transient local electric field. This absorption generates electron-hole pairs that then contribute to the device current, and a transient optical output is predicted. Carriers in the semiconductor layers are generated through thermal excitation or optical absorption, move under the action of diffusion and self-consistent electric fields updated at each time step by a 1D Poisson solver, and recombine at density-dependent rates. The different epi layers are independently specified by position, thickness, doping type and density, and thus space charge effects and junction capacitance are included automatically.« less

  19. What Are Chia Seeds?

    MedlinePlus

    ... Men For Women For Seniors What Are Chia Seeds? Published February 05, 2014 Print Email When you ... number of research participants. How to Eat Chia Seeds Chia seeds can be eaten raw or prepared ...

  20. Autoradiographic localization of epidermal growth factor receptors to all major uterine cell types

    SciTech Connect

    Lin, T.H.; Mukku, V.R.; Verner, G.; Kirkland, J.L.; Stancel, G.M.

    1988-03-01

    We have recently studied the structure and function of the uterine epidermal growth factor (EGF) receptor, its hormonal regulation, and its possible role in estrogen-induced uterine DNA synthesis. Since the uterus is composed of multiple cell types, we sought, in the work reported here, to localize EGF binding in this organ by autoradiography. Prior to the actual autoradiography, we performed a companion series of experiments to insure that EGF binding to uterine tissue in situ represented a true receptor interaction. Uteri from immature female rats were incubated in vitro with 125I-EGF at 25 degrees C. Tissue binding was maximal within 120 min and remained constant for at least an additional 120 min. This binding of labeled EGF was largely abolished by excess unlabeled EGF but not by other growth factors, indicating that binding was to specific receptors. The binding of 125I-EGF was saturable and reached a plateau at 4-8 nM; specific binding was half-maximal at 1-2 nM EGF. In situ cross-linking studies revealed that 125I-EGF was bound predominantly to a 170,000 MW EGF receptor similar to that seen in isolated uterine membranes. Incubation of uteri with 125I-EGF followed by autoradiography revealed binding to epithelial cells, stroma, and myometrium. These results provide evidence for the presence of specific EGF receptors in all major uterine cell types of the immature rat.

  1. Bean Seed Imbibition.

    ERIC Educational Resources Information Center

    Hershey, David R.

    1998-01-01

    Enables students to examine the time course for seed imbibition and the pressure generated by imbibing seeds. Provides background information, detailed procedures, and ideas for further investigation. (DDR)

  2. Iodoamphetamine as a new tracer for local cerebral blood flow in the rat: comparison with isopropyliodoamphetamine.

    PubMed

    Rapin, J R; Le Poncin-Lafitte, M; Duterte, D; Rips, R; Morier, E; Lassen, N A

    1984-06-01

    Rats were injected with iodoamphetamine synthesized and labeled with 125I or with 125I- isopropyliodoamphetamine , a molecule of established value for the determination of local cerebral blood flow. The blood kinetics, tissue distribution, and brain uptake index for each tracer exhibited practically no differences. Autoradiographic quantification of the local cerebral blood flow, calculated according to the microsphere model, produced identical results for both molecules. However, compared with the values reported for other tracers, our values constituted an underestimation of white matter blood flow and a more real estimation of hippocampal flow. It is concluded from the brain uptake of the derivatives of both amphetamines during the first minutes following their injection that these tracers can be used as a chemical microembolus for the measurement of local cerebral blood flow. PMID:6725437

  3. Iodoamphetamine as a new tracer for local cerebral blood flow in the rat: comparison with isopropyliodoamphetamine

    SciTech Connect

    Rapin, J.R.; Le Poncin-Lafitte, M.; Duterte, D.; Rips, R.; Morier, E.; Lassen, N.A.

    1984-06-01

    Rats were injected with iodoamphetamine synthesized and labeled with /sup 125/I or with /sup 125/I- isopropyliodoamphetamine, a molecule of established value for the determination of local cerebral blood flow. The blood kinetics, tissue distribution, and brain uptake index for each tracer exhibited practically no differences. Autoradiographic quantification of the local cerebral blood flow, calculated according to the microsphere model, produced identical results for both molecules. However, compared with the values reported for other tracers, our values constituted an underestimation of white matter blood flow and a more real estimation of hippocampal flow. It is concluded from the brain uptake of the derivatives of both amphetamines during the first minutes following their injection that these tracers can be used as a chemical microembolus for the measurement of local cerebral blood flow.

  4. Relationship between isotope half-life and prostatic edema for optimal prostate dose coverage in permanent seed implants

    SciTech Connect

    Villeneuve, Maxime; Leclerc, Ghyslain; Lessard, Etienne; Pouliot, Jean; Beaulieu, Luc

    2008-05-15

    The robustness of treatment planning to prostatic edema for three different isotopes ({sup 125}I, {sup 103}Pd, and {sup 131}Cs) is explored using dynamical dose calculations on 25 different clinical prostate cases. The treatment plans were made using the inverse planning by simulated annealing (IPSA) algorithm. The prescription was 144, 127, and 125 Gy for {sup 125}I, {sup 131}Cs, and {sup 103}Pd, respectively. For each isotope, three dose distribution schemes were used to impose different protection levels to the urethra: V{sub 120}=0%, V{sub 150}=0%, and V{sub 150}=30%. Eleven initial edema values were considered ranging from 1.0 (no edema) to 2.0 (100%). The edema was assumed to resolve exponentially with time. The prostate volume, seed positions, and seed activity were dynamically tracked to produce the final dose distribution. Edema decay half-lives of 10, 30, and 50 days were used. A total of 675 dynamical calculations were performed for each initial edema value. For the {sup 125}I isotope, limiting the urethra V{sub 120} to 0% leads to a prostate D{sub 90} under 140 Gy for initial edema values above 1.5. Planning with urethra V{sub 150} at 0% provides a good response to the edema; the prostate D{sub 90} remains higher than 140 Gy for edema values up to 1.8 and a half-life of 30 days or less. For {sup 103}Pd, the prostate D{sub 90} is under 97% of the prescription dose for approximately 66%, 40%, and 30% of edema values for urethra V{sub 120}=0%, V{sub 150}=0%, and V{sub 150}=30%, respectively. Similar behavior is seen for {sup 131}Cs and the center of the prostate becomes 'cold' for almost all edema scenarios. The magnitude of the edema following prostate brachytherapy, as well as the half-life of the isotope used and that of the edema resorption, all have important impacts on the dose distribution. The {sup 125}I isotope with its longer half-life is more robust to prostatic edema. Setting up good planning objectives can provide an adequate compromise

  5. Improving photoacoustic imaging contrast of brachytherapy seeds

    NASA Astrophysics Data System (ADS)

    Pan, Leo; Baghani, Ali; Rohling, Robert; Abolmaesumi, Purang; Salcudean, Septimiu; Tang, Shuo

    2013-03-01

    Prostate brachytherapy is a form of radiotherapy for treating prostate cancer where the radiation sources are seeds inserted into the prostate. Accurate localization of seeds during prostate brachytherapy is essential to the success of intraoperative treatment planning. The current standard modality used in intraoperative seeds localization is transrectal ultrasound. Transrectal ultrasound, however, suffers in image quality due to several factors such speckle, shadowing, and off-axis seed orientation. Photoacoustic imaging, based on the photoacoustic phenomenon, is an emerging imaging modality. The contrast generating mechanism in photoacoustic imaging is optical absorption that is fundamentally different from conventional B-mode ultrasound which depicts changes in acoustic impedance. A photoacoustic imaging system is developed using a commercial ultrasound system. To improve imaging contrast and depth penetration, absorption enhancing coating is applied to the seeds. In comparison to bare seeds, approximately 18.5 dB increase in signal-to-noise ratio as well as a doubling of imaging depth are achieved. Our results demonstrate that the coating of the seeds can further improve the discernibility of the seeds.

  6. Comparison of seed loading approaches in prostate brachytherapy.

    PubMed

    Butler, W M; Merrick, G S; Lief, J H; Dorsey, A T

    2000-02-01

    Since uniform seed loading in prostate brachytherapy can produce an intolerably high dose along the urethra, some form of peripheral loading is commonly employed. We define three variants of peripheral loading and compare them in a small, medium, and large prostate in terms of coverage of the planning target volume (PTV), homogeneity, and ability to spare critical structures of excessive dose. Modified uniform loading has at least 2/3 of the seeds occupying sites on a 1 cm cubic grid keyed to the prostate base and the posterior border of the prostate. Nonuniform loading explicitly spares the urethra by using only basal and apical seeds in at least two centrally located needles. Peripheral loading uses higher activity seeds with the posterior implant plane 5 mm anterior to the posterior border of the prostate. The three prostate volumes (18.7, 40.7, and 60.2 cm3 by ultrasound) were expanded to planning volumes (32.9, 60.0, and 87.8 cm3, respectively). The planning volumes (PTVs) were loaded with a 125I seed distribution and activity sufficient to cover 99.7+/-0.3% of the PTV with the prescribed minimal peripheral dose (mPD) of 145 Gy. Activities used ranged from 0.32 to 0.37 mCi/seed (0.41-0.47 U/seed) for the first two approaches and from 0.57 to 0.66 mCi (0.72-0.84 U) for peripheral loading. Modified uniform loading produced the most uniform distribution based on dose-volume histograms and the volume receiving >150% of prescribed dose. All the approaches are capable of constraining the superior-inferior dose profile (the urethral path) to less than 150% of the mPD, but the nonuniform approach with explicit urethral sparing kept the urethral dose below 120% of the mPD. Dose profiles for the three approaches along the posterior-anterior midline axis are comparable near the urethra, but peripheral and nonuniform approaches have extended regions where the dose is >150% of mPD. These regions approach within 10 mm of the rectum or urethra, so these two approaches

  7. Seed morphology characteristics in relation to seed loss by water erosion in the Loess Plateau.

    PubMed

    Jiao, Juying; Han, Luyan; Jia, Yanfeng; Lei, Dong; Wang, Ning; Li, Linyu

    2013-01-01

    The role of water erosion on seed loss and on plant establishment and distribution is unknown on the Chinese Loess Plateau, which suffers serious soil erosion. The seed susceptibility of 16 local species to removal by water erosion from loess slopes was determined by rainfall simulation experiments. The experiments were performed on slopes with gradients of 10°, 15°, 20° and 25° for a 60-min duration at an intensity of 50 mm/h, 100 mm/h and 150 mm/h, respectively. The total seed removal rate obviously increased with rainfall intensity but did not obviously change with slope gradient, and the responses were varied among the species. The morphological characteristics affecting seed loss of the various species are quite different. Our experiments showed that the seed removal from some species are mainly due to seed weight, some species are mainly affected by seed shape, some are affected by appendage, some by surface structure, some by the comprehensive effects of the different morphological characteristics, while seeds having mucilage secretion are not easily moved by water erosion. We argued that the seed removal during water erosion can clearly effect seed redistribution and deposition, and consequently, species composition and vegetation spatial distribution.

  8. Grazing impact on desert plants and soil seed banks: Implications for seed-eating animals

    NASA Astrophysics Data System (ADS)

    Pol, Rodrigo G.; Sagario, M. Cecilia; Marone, Luis

    2014-02-01

    We assess whether the knowledge of livestock diet helps to link grazing effects with changes in plant cover and soil seed bank size, aiming at inferring the consequences of grazing on seed-eating animals. Specifically, we test whether continuous and heavy grazing reduce the cover, number of reproductive structures and seed reserves of the same grass species whose seeds are selected and preferred by granivorous animals in the central Monte desert, Argentina. Grass cover and the number of grass spikes usually diminished under grazing conditions in the two localities studied (Telteca and Ñacuñán), and soil seed bank was consistently reduced in all three years evaluated owing to a decline of perennial grass and forb seeds. In particular, the abundance of those seeds selected and preferred by birds and ants (in all cases grass species) declined 70-92% in Ñacuñán, and 52-72% in Telteca. Reduction of perennial grass cover and spike number in grazed sites reinforced the causal link between livestock grazing and the decline of grass soil seed reserves throughout failed plant reproduction. Grass seed bank depletion suggests that grazing may trigger a "cascade" of mechanisms that affect the abundance and persistence of valuable fodder species as well as the availability of seed resources for granivorous animals.

  9. Seeds of hope, seeds of despair: towards a political economy of the seed industry in southern Africa.

    PubMed

    Zerbe, N

    2001-01-01

    The seed industry in Southern Africa has been radically transformed by a policy of liberalisation and privatisation started under structural adjustment. Traditionally under the domain of parastatals, seed research, production and distribution has been criticised for failing to provide modern variety seed to smallholder farmers. However, the private companies which have stepped in to replace seed parastatals in southern Africa have proven no more effective in meeting the demands of smallholders. The Trade Related Intellectual Property Rights (TRIPs) Agreement, concluded in 1994 as part of the Uruguay Rounds of GATT negotiations, as well as certain biotechnological innovations such as Terminator or Traitor technologies, threaten to further undermine local seed production and consumption by destroying the informal seed sector so central to agricultural production in the region. What alternatives exist? The success of Zimbabwe's maize seed network offers some insight. Resting on a unique relationship between government and nationally based producer co-operatives, Zimbabwe's maize programme was able to provide nearly every farmer in the country with hybrid maize suited for local growing conditions.

  10. Identification of a characteristic antioxidant, anthrasesamone F, in black sesame seeds and its accumulation at different seed developmental stages.

    PubMed

    Furumoto, Toshio; Nishimoto, Kiyoshi

    2016-01-01

    Assay-guided fractionation of the methanol extract from black seeds of sesame (Sesamum indicum L.) led to the isolation of an active compound that had a 1,1-diphenyl-2-picrylhydrazyl radical scavenging activity. This antioxidant was confirmed to be anthrasesamone F, an anthraquinone derivative previously isolated from different black sesame seeds and biogenetically related to other anthrasesamones in sesame roots. The radical scavenging assay showed that anthrasesamone F had more potent activity than Trolox. The content of anthrasesamone F in different parts and at different developmental stages of black sesame seeds was investigated to clarify the accumulation pattern of this antioxidant in the black seeds. Anthrasesamone F was localized in the seed coat of black seeds and accumulated after the seed coat color changed to black. The content of anthrasesamone F increased gradually with seed maturation and drastically on air-drying, the final stage in sesame cultivation.

  11. Dosimetry of a thyroid uptake detected in seed migration survey following a patient's iodine-125 prostate implant and in vitro measurements of intentional seed leakages

    SciTech Connect

    Chen Qinsheng; Russell, John L. Jr.; Macklis, Roger R.; Weinhous, Martin S.; Blair, Henry F.

    2006-07-15

    As a quality control procedure, a post-implant seed migration survey has been accomplished on 340 prostate cancer patients since November 2001. Pulmonary seed embolization and intracardiac seed embolization have been detected. A case of thyroid uptake due to leaking iodine-125 (I-125) sources was also seized. In order to determine the dose to the thyroid, a dosimetry method was developed to link in vivo measurements and the cumulated dose to the thyroid. The calculated source leakage half-life in the case was approximately 15 days based on the measurements and the estimated cumulated dose to thyroid was 204 cGy. It is concluded that one seed was leaking. In order to verify the in vivo measurements, intentional in vitro seed leakage tests were performed. A seed was cut open and placed in a sealed glass container filled with a given volume of saline. The I-125 concentration in the saline was subsequently measured over a period of six months. Consistent in vivo and in vitro results were obtained. Recent incidents of seed leaks reported from other centers have drawn practitioners' attention to this problem. In order to make the measurements more useful, the seed leakage tests were expanded to include I-125 seeds from six other vendors. The results show that the leakage half-lives of those seeds varied from nine days to a half-year. Two seed models demonstrated least leakage. Since the measurements lasted for six months, the escape of iodine resulted from oxidation of iodide in the saline was a concern for the measurement accuracy. As a reference, another set of leakage tests were performed by adding sodium thiosulfate salt (Na{sub 2}S{sub 2}O{sub 3}{center_dot}5H{sub 2}O) to the saline. Sodium thiosulfate is a reducing agent that prevents the conversion of iodide to iodate so as to minimize I-125 evaporation. As a result, significantly shortened leakage half-lives were observed in this group. Seed agitation was also performed and no significant deviations of the

  12. A crop population perspective on maize seed systems in Mexico

    PubMed Central

    Dyer, George A.; Taylor, J. Edward

    2008-01-01

    Improvement of local germplasm through artificial selection is regarded as the main force behind maize evolution and diversity in Mexico, the crop's center of origin. This perspective neglects the larger social context of maize evolution. Using a theoretical approach and Mexico-wide data, we show that farmer-led evolution of maize is largely driven by a technological diffusion and appropriation process that selectively integrates nonlocal germplasm into local seed stocks. Our approach construes farmer practices as events in the life history of seed to build a demographic model. The model shows how random and systematic differences in management combine to structure maize seed populations into subpopulations that can spread or become extinct, in some cases independently of visible agronomic advantages. The process involves continuous population bottlenecks that can lead to diversity loss. Nonlocal germplasm thus might play a critical role in maintaining diversity in individual localities. Empirical estimates show that introduction of nonlocal seed in Central and Southeastern Mexico is rarer than previously thought; prompt replacement further prevents new seed from spreading. Yet introduced seed perceived as valuable diffuses rapidly, contributing variation in the form of type diversity or through introgression into local seed. Maize seed dynamics and evolution are thus part of a complex social process driven by farmers' desire to appropriate the value in maize farming, not always achieved by preserving or improving local seed stocks. PMID:18184814

  13. Seed predation, not seed dispersal, explains the landscape-level abundance of an early-successional plant.

    SciTech Connect

    Orrock, John, L.; Douglas J. Levey; Brent J. Danielson; Ellen I Damschen.

    2006-01-01

    Plants may not occur in a given area if there are no suitable sites for seeds to establish (microsite limitation), if seeds fail to arrive in suitable microsites (dispersal limitation) or if seeds in suitable microsites are destroyed by predators (predator limitation). When dispersal and microsites are not limiting, the role of local seed predators can be important for generating emergent, large-scale patterns of plant abundance across landscapes. Moreover, because predators may generate large-scale patterns that resemble other forms of limitation and predators may target specific species, predator impacts should be more frequently incorporated into experiments on the role of seed limitation and plant community composition.

  14. 7 CFR 201.18 - Other agricultural seeds (crop seeds).

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 3 2013-01-01 2013-01-01 false Other agricultural seeds (crop seeds). 201.18 Section... SERVICE (Standards, Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE (CONTINUED) FEDERAL SEED ACT FEDERAL SEED ACT REGULATIONS Labeling Agricultural Seeds § 201.18 Other agricultural seeds...

  15. 7 CFR 201.18 - Other agricultural seeds (crop seeds).

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 3 2014-01-01 2014-01-01 false Other agricultural seeds (crop seeds). 201.18 Section... SERVICE (Standards, Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE (CONTINUED) FEDERAL SEED ACT FEDERAL SEED ACT REGULATIONS Labeling Agricultural Seeds § 201.18 Other agricultural seeds...

  16. 7 CFR 201.18 - Other agricultural seeds (crop seeds).

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 3 2012-01-01 2012-01-01 false Other agricultural seeds (crop seeds). 201.18 Section... SERVICE (Standards, Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE (CONTINUED) FEDERAL SEED ACT FEDERAL SEED ACT REGULATIONS Labeling Agricultural Seeds § 201.18 Other agricultural seeds...

  17. 7 CFR 201.18 - Other agricultural seeds (crop seeds).

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 3 2010-01-01 2010-01-01 false Other agricultural seeds (crop seeds). 201.18 Section... SERVICE (Standards, Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE (CONTINUED) FEDERAL SEED ACT FEDERAL SEED ACT REGULATIONS Labeling Agricultural Seeds § 201.18 Other agricultural seeds...

  18. 7 CFR 201.18 - Other agricultural seeds (crop seeds).

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 3 2011-01-01 2011-01-01 false Other agricultural seeds (crop seeds). 201.18 Section... SERVICE (Standards, Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE (CONTINUED) FEDERAL SEED ACT FEDERAL SEED ACT REGULATIONS Labeling Agricultural Seeds § 201.18 Other agricultural seeds...

  19. Seed Treatment. Sale Publication 4076.

    ERIC Educational Resources Information Center

    Wamsley, Mary Ann, Ed.; Vermeire, Donna M., Ed.

    This guide gives information about types of seeds that may require chemical protection against pests, seed treatment pesticide formulations, seed treatment methods, labeling treated seed, and safety and environmental precautions. (Author/BB)

  20. Healthy food trends -- chia seeds

    MedlinePlus

    ... Healthy food trends - salvia; Healthy snacks - Chia seeds; Weight loss - Chia seeds; Healthy diet - Chia seeds; Wellness - Chia ... fiber. Some think chia seeds may help with weight loss and other risk factors, but this has not ...

  1. Seed Proteomics"

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Proteomic analysis of seeds encounters some specific problems that do not impinge on analyses of other plant cells, tissues, or organs. There are anatomic considerations. Seeds comprise the seed coat, the storage organ(s), and the embryonic axis. Are these to be studied individually or as a compo...

  2. Going to Seed.

    ERIC Educational Resources Information Center

    Powell, Richard R.

    1984-01-01

    Describes a unit on seeds designed to introduce students to their scientific and nutritional uses. Unit activities are easily done, employ a variety of process skills, and can be used at various grade levels. Suggests field trips to gather seeds, seed sprouting, and making cookies out of various whole grains. (JM)

  3. Needs of Seeds

    ERIC Educational Resources Information Center

    Keeley, Page

    2011-01-01

    The "Needs of Seeds" formative assessment probe can be used to find out whether students recognize that seeds have needs both similar to and different from plants and other living organisms (Keeley, Eberle, and Tugel 2007). The probe reveals whether students overgeneralize the needs of seeds by assuming they have the same needs as the adult plants…

  4. Transection of Radioactive Seeds in Breast Specimens.

    PubMed

    Gilcrease, Michael Z; Dogan, Basak E; Black, Dalliah M; Contreras, Alejandro; Dryden, Mark J; Jimenez, Sandra M

    2016-10-01

    Radioactive seed localization is a new procedure for localizing breast lesions that has several advantages over the standard wire-localization procedure. It is reported to be safe for both patients and medical personnel. Although it is theoretically possible to transect the titanium-encapsulated seed while processing the breast specimen in the pathology laboratory, the likelihood of such an event is thought to be exceedingly low. In fact, there are no previous reports of such an event in the literature to date. We recently encountered 2 cases in which a radioactive seed was inadvertently transected while slicing a breast specimen at the grossing bench. In this report, we describe each case and offer recommendations for minimizing radioactive exposure to personnel and for preventing radioactive contamination of laboratory equipment. PMID:27627744

  5. Corticotropin-releasing factor (CRF) receptors in intermediate lobe of the pituitary: Biochemical characterization and autoradiographic localization

    SciTech Connect

    Grigoriadis, D.E.; De Souza, E.B.

    1989-01-01

    CRF receptors were characterized using radioligand binding and chemical affinity cross-linking techniques and localized using autoradiographic techniques in porcine, bovine and rat pituitaries. The binding of 125I-(Tyr0)-ovine CRF (125I-oCRF) to porcine anterior and neurointermediate lobe membranes was saturable and of high affinity with comparable KD values (200-600 pM) and receptor densities (100-200 fmoles/mg protein). The pharmacological rank order of potencies for various analogs and fragments of CRF in inhibiting 125I-oCRF binding in neurointermediate lobe was characteristic of the well-established CRF receptor in anterior pituitary. Furthermore, the binding of 125I-oCRF to both anterior and neurointermediate lobes of the pituitary was guanine nucleotide-sensitive. Affinity cross-linking studies revealed that the molecular weight of the CRF binding protein in rat intermediate lobe was identical to that in rat anterior lobe (Mr = 75,000). While the CRF binding protein in the anterior lobes of porcine and bovine pituitaries had identical molecular weights to CRF receptors in rat pituitary (Mr = 75,000), the molecular weight of the CRF binding protein in porcine and bovine intermediate lobe was slightly higher (Mr = 78,000). Pituitary autoradiograms from the three species showed specific binding sites for 125I-oCRF in anterior and intermediate lobes, with none being apparent in the posterior pituitary. The identification of CRF receptors in the intermediate lobe with comparable characteristics to those previously identified in the anterior pituitary substantiate further the physiological role of CRF in regulating intermediate lobe hormone secretion.

  6. Arabidopsis seed-specific vacuolar aquaporins are involved in maintaining seed longevity under the control of ABSCISIC ACID INSENSITIVE 3

    PubMed Central

    Mao, Zhilei; Sun, Weining

    2015-01-01

    The tonoplast intrinsic proteins TIP3;1 and TIP3;2 are specifically expressed during seed maturation and localized to the seed protein storage vacuole membrane. However, the function and physiological roles of TIP3s are still largely unknown. The seed performance of TIP3 knockdown mutants was analysed using the controlled deterioration test. The tip3;1/tip3;2 double mutant was affected in seed longevity and accumulated high levels of hydrogen peroxide compared with the wild type, suggesting that TIP3s function in seed longevity. The transcription factor ABSCISIC ACID INSENSITIVE 3 (ABI3) is known to be involved in seed desiccation tolerance and seed longevity. TIP3 transcript and protein levels were significantly reduced in abi3-6 mutant seeds. TIP3;1 and TIP3;2 promoters could be activated by ABI3 in the presence of abscisic acid (ABA) in Arabidopsis protoplasts. TIP3 proteins were detected in the protoplasts transiently expressing ABI3 and in ABI3-overexpressing seedlings when treated with ABA. Furthermore, ABI3 directly binds to the RY motif of the TIP3 promoters. Therefore, seed-specific TIP3s may help maintain seed longevity under the expressional control of ABI3 during seed maturation and are members of the ABI3-mediated seed longevity pathway together with small heat shock proteins and late embryo abundant proteins. PMID:26019256

  7. Arabidopsis seed-specific vacuolar aquaporins are involved in maintaining seed longevity under the control of ABSCISIC ACID INSENSITIVE 3.

    PubMed

    Mao, Zhilei; Sun, Weining

    2015-08-01

    The tonoplast intrinsic proteins TIP3;1 and TIP3;2 are specifically expressed during seed maturation and localized to the seed protein storage vacuole membrane. However, the function and physiological roles of TIP3s are still largely unknown. The seed performance of TIP3 knockdown mutants was analysed using the controlled deterioration test. The tip3;1/tip3;2 double mutant was affected in seed longevity and accumulated high levels of hydrogen peroxide compared with the wild type, suggesting that TIP3s function in seed longevity. The transcription factor ABSCISIC ACID INSENSITIVE 3 (ABI3) is known to be involved in seed desiccation tolerance and seed longevity. TIP3 transcript and protein levels were significantly reduced in abi3-6 mutant seeds. TIP3;1 and TIP3;2 promoters could be activated by ABI3 in the presence of abscisic acid (ABA) in Arabidopsis protoplasts. TIP3 proteins were detected in the protoplasts transiently expressing ABI3 and in ABI3-overexpressing seedlings when treated with ABA. Furthermore, ABI3 directly binds to the RY motif of the TIP3 promoters. Therefore, seed-specific TIP3s may help maintain seed longevity under the expressional control of ABI3 during seed maturation and are members of the ABI3-mediated seed longevity pathway together with small heat shock proteins and late embryo abundant proteins. PMID:26019256

  8. The seed nuclear proteome

    PubMed Central

    Repetto, Ombretta; Rogniaux, Hélène; Larré, Colette; Thompson, Richard; Gallardo, Karine

    2012-01-01

    Understanding the regulatory networks coordinating seed development will help to manipulate seed traits, such as protein content and seed weight, in order to increase yield and seed nutritional value of important food crops, such as legumes. Because of the cardinal role of the nucleus in gene expression, sub-proteome analyses of nuclei from developing seeds were conducted, taking advantage of the sequences available for model species. In this review, we discuss the strategies used to separate and identify the nuclear proteins at a stage when the seed is preparing for reserve accumulation. We present how these data provide an insight into the complexity and distinctive features of the seed nuclear proteome. We discuss the presence of chromatin-modifying enzymes and proteins that have roles in RNA-directed DNA methylation and which may be involved in modifying genome architecture in preparation for seed filling. Specific features of the seed nuclei at the transition between the stage of cell divisions and that of cell expansion and reserve deposition are described here which may help to manipulate seed quality traits, such as seed weight. PMID:23267364

  9. Seed exchange networks, ethnicity, and sorghum diversity

    PubMed Central

    Labeyrie, Vanesse; Thomas, Mathieu; Muthamia, Zachary K.; Leclerc, Christian

    2016-01-01

    Recent studies investigating the relationship between crop genetic diversity and human cultural diversity patterns showed that seed exchanges are embedded in farmers’ social organization. However, our understanding of the social processes involved remains limited. We investigated how farmers’ membership in three major social groups interacts in shaping sorghum seed exchange networks in a cultural contact zone on Mount Kenya. Farmers are members of residence groups at the local scale and of dialect groups clustered within larger ethnolinguistic units at a wider scale. The Chuka and Tharaka, who are allied in the same ethnolinguistic unit, coexist with the Mbeere dialect group in the study area. We assessed farmers’ homophily, propensity to exchange seeds with members of the same group, using exponential random graph models. We showed that homophily is significant within both residence and ethnolinguistic groups. At these two levels, homophily is driven by the kinship system, particularly by the combination of patrilocal residence and ethnolinguistic endogamy, because most seeds are exchanged among relatives. Indeed, residential homophily in seed exchanges results from local interactions between women and their in-law family, whereas at a higher level, ethnolinguistic homophily is driven by marriage endogamy. Seed exchanges and marriage ties are interrelated, and both are limited between the Mbeere and the other groups, although frequent between the Chuka and Tharaka. The impact of these social homophily processes on crop diversity is discussed. PMID:26699480

  10. Seed exchange networks, ethnicity, and sorghum diversity.

    PubMed

    Labeyrie, Vanesse; Thomas, Mathieu; Muthamia, Zachary K; Leclerc, Christian

    2016-01-01

    Recent studies investigating the relationship between crop genetic diversity and human cultural diversity patterns showed that seed exchanges are embedded in farmers' social organization. However, our understanding of the social processes involved remains limited. We investigated how farmers' membership in three major social groups interacts in shaping sorghum seed exchange networks in a cultural contact zone on Mount Kenya. Farmers are members of residence groups at the local scale and of dialect groups clustered within larger ethnolinguistic units at a wider scale. The Chuka and Tharaka, who are allied in the same ethnolinguistic unit, coexist with the Mbeere dialect group in the study area. We assessed farmers' homophily, propensity to exchange seeds with members of the same group, using exponential random graph models. We showed that homophily is significant within both residence and ethnolinguistic groups. At these two levels, homophily is driven by the kinship system, particularly by the combination of patrilocal residence and ethnolinguistic endogamy, because most seeds are exchanged among relatives. Indeed, residential homophily in seed exchanges results from local interactions between women and their in-law family, whereas at a higher level, ethnolinguistic homophily is driven by marriage endogamy. Seed exchanges and marriage ties are interrelated, and both are limited between the Mbeere and the other groups, although frequent between the Chuka and Tharaka. The impact of these social homophily processes on crop diversity is discussed. PMID:26699480

  11. Seed exchange networks, ethnicity, and sorghum diversity.

    PubMed

    Labeyrie, Vanesse; Thomas, Mathieu; Muthamia, Zachary K; Leclerc, Christian

    2016-01-01

    Recent studies investigating the relationship between crop genetic diversity and human cultural diversity patterns showed that seed exchanges are embedded in farmers' social organization. However, our understanding of the social processes involved remains limited. We investigated how farmers' membership in three major social groups interacts in shaping sorghum seed exchange networks in a cultural contact zone on Mount Kenya. Farmers are members of residence groups at the local scale and of dialect groups clustered within larger ethnolinguistic units at a wider scale. The Chuka and Tharaka, who are allied in the same ethnolinguistic unit, coexist with the Mbeere dialect group in the study area. We assessed farmers' homophily, propensity to exchange seeds with members of the same group, using exponential random graph models. We showed that homophily is significant within both residence and ethnolinguistic groups. At these two levels, homophily is driven by the kinship system, particularly by the combination of patrilocal residence and ethnolinguistic endogamy, because most seeds are exchanged among relatives. Indeed, residential homophily in seed exchanges results from local interactions between women and their in-law family, whereas at a higher level, ethnolinguistic homophily is driven by marriage endogamy. Seed exchanges and marriage ties are interrelated, and both are limited between the Mbeere and the other groups, although frequent between the Chuka and Tharaka. The impact of these social homophily processes on crop diversity is discussed.

  12. Seed harvesting by a generalist consumer is context-dependent: Interactive effects across multiple spatial scales

    USGS Publications Warehouse

    Ostoja, Steven M.; Schupp, Eugene W.; Klinger, Rob

    2013-01-01

    Granivore foraging decisions affect consumer success and determine the quantity and spatial pattern of seed survival. These decisions are influenced by environmental variation at spatial scales ranging from landscapes to local foraging patches. In a field experiment, the effects of seed patch variation across three spatial scales on seed removal by western harvester ants Pogonomyrmex occidentalis were evaluated. At the largest scale we assessed harvesting in different plant communities, at the intermediate scale we assessed harvesting at different distances from ant mounds, and at the smallest scale we assessed the effects of interactions among seed species in local seed neighborhoods on seed harvesting (i.e. resource–consumer interface). Selected seed species were presented alone (monospecific treatment) and in mixture with Bromus tectorum (cheatgrass; mixture treatment) at four distances from P. occidentalis mounds in adjacent intact sagebrush and non-native cheatgrass-dominated communities in the Great Basin, Utah, USA. Seed species differed in harvest, with B. tectorum being least preferred. Large and intermediate scale variation influenced harvest. More seeds were harvested in sagebrush than in cheatgrass-dominated communities (largest scale), and the quantity of seed harvested varied with distance from mounds (intermediate-scale), although the form of the distance effect differed between plant communities. At the smallest scale, seed neighborhood affected harvest, but the patterns differed among seed species considered. Ants harvested fewer seeds from mixed-seed neighborhoods than from monospecific neighborhoods, suggesting context dependence and potential associational resistance. Further, the effects of plant community and distance from mound on seed harvest in mixtures differed from their effects in monospecific treatments. Beyond the local seed neighborhood, selection of seed resources is better understood by simultaneously evaluating removal at

  13. Spatial variation in post-dispersal seed removal in an Atlantic forest: Effects of habitat, location and guilds of seed predators

    NASA Astrophysics Data System (ADS)

    Christianini, Alexander V.; Galetti, Mauro

    2007-11-01

    Studies of post-dispersal seed removal in the Neotropics have rarely examined the magnitude of seed removal by different types of granivores. The relative impact of invertebrates, small rodents, and birds on seed removal was investigated in a 2,178 ha Atlantic forest fragment in southeastern Brazil. We used popcorn kernels ( Zea mays—Poaceae) to investigate seed removal in a series of selective exclosure treatments in a replicated, paired design experiment that included forest understory, gaps, and forest edge sites. We recorded the vegetation around the experimental seed stations in detail in order to evaluate the influence of microhabitat traits on seed removal. Vertebrate granivores (rodents and birds) were surveyed to determine whether granivore abundance was correlated with seed removal levels. Seed removal varied spatially and in unpredictable ways at the study site. Seed encounter and seed use varied with treatments, but not with habitat type. However, seed removal by invertebrates was negatively correlated with gap-related traits, which suggested an avoidance of large gaps by granivorous ants. The abundance of small mammals was remarkably low, but granivorous birds (tinamous and doves) were abundant at the study site. Birds were the main seed consumers in open treatments, but there was no correlation between local granivorous bird abundance and seed removal. These results emphasize the stochastic spatial pattern of seed removal, and, contrary to previous studies, highlight the importance of birds as seed predators in forest habitats.

  14. Two cytosolic glutamine synthetase isoforms play specific roles for seed germination and seed yield structure in Arabidopsis.

    PubMed

    Guan, M; Møller, I S; Schjoerring, J K

    2015-01-01

    Nitrogen (N) remobilization from reserves to sinks is essential for seedling establishment and seed production. Cytosolic glutamine synthetase (GS1) is up-regulated during both seed germination and seed filling in plants. However, the specific roles of the individual GS1 isogenes with respect to N remobilization, early seedling vigour, and final seed productivity are not known. In this study, impairment of seed germination and seedling establishment is demonstrated in the single knockout mutant gln1;2, and the double knockout mutant gln1;1:gln1;2. The negative effect of Gln1;2 deficiency was associated with reduced N remobilization from the cotyledons and could be fully alleviated by exogenous N supply. Following reproductive growth, both the single and double Gln1;2-knockout mutants showed decreased seed yield due to fewer siliques, less seeds per silique, and lower dry weight per seed. The gln1;1 single mutant had normal seed yield structure but primary root development during seed germination was reduced in the presence of external N. Gln1;2 promoter-green fluorescent protein constructs showed that Gln1;2 localizes to the vascular cells of roots, petals, and stamens. It is concluded that Gln1;2 plays an important role in N remobilization for both seedling establishment and seed production in Arabidopsis.

  15. Two cytosolic glutamine synthetase isoforms play specific roles for seed germination and seed yield structure in Arabidopsis

    PubMed Central

    Guan, M.; Møller, I. S.; Schjoerring, J. K.

    2015-01-01

    Nitrogen (N) remobilization from reserves to sinks is essential for seedling establishment and seed production. Cytosolic glutamine synthetase (GS1) is up-regulated during both seed germination and seed filling in plants. However, the specific roles of the individual GS1 isogenes with respect to N remobilization, early seedling vigour, and final seed productivity are not known. In this study, impairment of seed germination and seedling establishment is demonstrated in the single knockout mutant gln1;2, and the double knockout mutant gln1;1:gln1;2. The negative effect of Gln1;2 deficiency was associated with reduced N remobilization from the cotyledons and could be fully alleviated by exogenous N supply. Following reproductive growth, both the single and double Gln1;2-knockout mutants showed decreased seed yield due to fewer siliques, less seeds per silique, and lower dry weight per seed. The gln1;1 single mutant had normal seed yield structure but primary root development during seed germination was reduced in the presence of external N. Gln1;2 promoter–green fluorescent protein constructs showed that Gln1;2 localizes to the vascular cells of roots, petals, and stamens. It is concluded that Gln1;2 plays an important role in N remobilization for both seedling establishment and seed production in Arabidopsis. PMID:25316065

  16. EchoSeed Model 6733 Iodine-125 brachytherapy source: Improved dosimetric characterization using the MCNP5 Monte Carlo code

    SciTech Connect

    Mosleh-Shirazi, M. A.; Hadad, K.; Faghihi, R.; Baradaran-Ghahfarokhi, M.; Naghshnezhad, Z.; Meigooni, A. S.

    2012-08-15

    This study primarily aimed to obtain the dosimetric characteristics of the Model 6733 {sup 125}I seed (EchoSeed) with improved precision and accuracy using a more up-to-date Monte-Carlo code and data (MCNP5) compared to previously published results, including an uncertainty analysis. Its secondary aim was to compare the results obtained using the MCNP5, MCNP4c2, and PTRAN codes for simulation of this low-energy photon-emitting source. The EchoSeed geometry and chemical compositions together with a published {sup 125}I spectrum were used to perform dosimetric characterization of this source as per the updated AAPM TG-43 protocol. These simulations were performed in liquid water material in order to obtain the clinically applicable dosimetric parameters for this source model. Dose rate constants in liquid water, derived from MCNP4c2 and MCNP5 simulations, were found to be 0.993 cGyh{sup -1} U{sup -1} ({+-}1.73%) and 0.965 cGyh{sup -1} U{sup -1} ({+-}1.68%), respectively. Overall, the MCNP5 derived radial dose and 2D anisotropy functions results were generally closer to the measured data (within {+-}4%) than MCNP4c and the published data for PTRAN code (Version 7.43), while the opposite was seen for dose rate constant. The generally improved MCNP5 Monte Carlo simulation may be attributed to a more recent and accurate cross-section library. However, some of the data points in the results obtained from the above-mentioned Monte Carlo codes showed no statistically significant differences. Derived dosimetric characteristics in liquid water are provided for clinical applications of this source model.

  17. An experimental palladium-103 seed (OptiSeed{sup exp}) in a biocompatible polymer without a gold marker: Characterization of dosimetric parameters including the interseed effect

    SciTech Connect

    Abboud, F.; Scalliet, P.; Vynckier, S.

    2008-12-15

    Permanent implantation of {sup 125}I (iodine) or {sup 103}Pd (palladium) sources is a popular treatment option in the management of early stage prostate cancer. New sources are being developed, some of which are being marketed for different clinical applications. A new technique of adjuvant stereotactic permanent seed breast implant, similar to that used in the treatment of prostate cancer, has been proposed by [N. Jansen et al., Int. J. Radiat. Oncol. Biol. Phys. 67, 1052-1058 (2007)] with encouraging results. The presence of artifacts from the metallic seeds, however, can disturb follow-up imaging. The development of plastic seeds has reduced these artifacts. This paper presents a feasibility study of the advantages of palladium-103 seeds, encapsulated with a biocompatible polymer, for future clinical applications, and on the effect of the gold marker on the dosimetric characteristics of such seeds. Experimental palladium seeds, OptiSeed{sup exp}, were manufactured by International Brachytherapy (IBt), Seneffe, Belgium, from a biocompatible polymer, including the marker. Apart from the absence of a gold marker, the studied seed has an identical design to the OptiSeed{sup 103}[Phys. Med. Biol. 50, 1493-1504 (2005)]; [Appl. Radiat. Isot. 63, 311-321 (2005)]. Polymer encapsulation was preferred by IBt in order to reduce the quantity of radioactive material needed for a given dose rate and to reduce the anisotropy of the radiation field around the seed. In addition, this design is intended to decrease the interseed effects that can occur as a result of the marker and the encapsulation. Dosimetric measurements were performed using LiF thermoluminescent dosimeters (1 mm{sup 3}) in solid water phantoms (WT1). Measured data were compared to Monte Carlo simulated data in solid water using the MCNP code, version 4C. Updated cross sections [Med. Phys. 30, 701-711 (2003)] were used. As the measured and calculated data were in agreement, Monte Carlo calculations were then

  18. Physiology of Oil Seeds

    PubMed Central

    Ketring, D. L.; Morgan, P. W.

    1971-01-01

    Germination, ethylene production, and carbon dioxide production by dormant Virginia-type peanuts were determined during treatments with plant growth regulators. Kinetin, benzylaminopurine, and 2-chloroethylphosphonic acid induced extensive germination above the water controls. Benzylaminopurine and 2-chloroethylphosphonic acid increased the germination of the more dormant basal seeds to a larger extent above the controls than the less dormant apical seeds. Coumarin induced a slight stimulation of germination while abscisic acid, 2,4-dichlorophenoxyacetic acid, and succinic acid 2,2-dimethylhydrazide did not stimulate germination above the controls. In addition to stimulating germination, the cytokinins also stimulated ethylene production by the seeds. In the case of benzylaminopurine, where the more dormant basal seeds were stimulated to germinate above the control to a larger extent than the less dormant apical seeds, correspondingly more ethylene production was induced in the basal seeds. However, the opposite was true of kinetin for both germination and ethylene production. When germination was extensively stimulated by the cytokinins, maximal ethylene and carbon dioxide evolution occurred at 24 and 72 hours, respectively. Abscisic acid inhibited ethylene production and germinaton of the seeds while carbon dioxide evolution was comparatively high. The crucial physiological event for germination of dormant peanut seeds was enhancement of ethylene production by the seeds. PMID:16657647

  19. A role for seed storage proteins in Arabidopsis seed longevity.

    PubMed

    Nguyen, Thu-Phuong; Cueff, Gwendal; Hegedus, Dwayne D; Rajjou, Loïc; Bentsink, Leónie

    2015-10-01

    Proteomics approaches have been a useful tool for determining the biological roles and functions of individual proteins and identifying the molecular mechanisms that govern seed germination, vigour and viability in response to ageing. In this work the dry seed proteome of four Arabidopsis thaliana genotypes, that carry introgression fragments at the position of seed longevity quantitative trait loci and as a result display different levels of seed longevity, was investigated. Seeds at two physiological states, after-ripened seeds that had the full germination ability and aged (stored) seeds of which the germination ability was severely reduced, were compared. Aged dry seed proteomes were markedly different from the after-ripened and reflected the seed longevity level of the four genotypes, despite the fact that dry seeds are metabolically quiescent. Results confirmed the role of antioxidant systems, notably vitamin E, and indicated that protection and maintenance of the translation machinery and energy pathways are essential for seed longevity. Moreover, a new role for seed storage proteins (SSPs) was identified in dry seeds during ageing. Cruciferins (CRUs) are the most abundant SSPs in Arabidopsis and seeds of a triple mutant for three CRU isoforms (crua crub cruc) were more sensitive to artificial ageing and their seed proteins were highly oxidized compared with wild-type seeds. These results confirm that oxidation is involved in seed deterioration and that SSPs buffer the seed from oxidative stress, thus protecting important proteins required for seed germination and seedling formation.

  20. Radio-guided occult lesion localisation using iodine 125 Seeds “ROLLIS” to guide surgical removal of an impalpable posterior chest wall melanoma metastasis

    SciTech Connect

    Dissanayake, Shashini; Dissanayake, Deepthi; Taylor, Donna B

    2015-09-15

    Cancer screening and surveillance programmes and the use of sophisticated imaging tools such as positron emission tomography-computed tomography (PET-CT) have increased the detection of impalpable lesions requiring imaging guidance for excision. A new technique involves intra-lesional insertion of a low-activity iodine-125 ({sup 125}I) seed and detection of the radioactive signal in theatre using a hand-held gamma probe to guide surgery. Whilst several studies describe using this method to guide the removal of impalpable breast lesions, only a handful of publications report its use to guide excision of lesions outside the breast. We describe a case in which radio-guided occult lesion localisation using an iodine 125 seed was used to guide excision of an impalpable posterior chest wall metastasis detected on PET-CT.

  1. Interaction between maize seed and Aspergillus flavus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Aspergillus flavus is an opportunistic fungal pathogen that colonizes maize seeds and contaminates them with aflatoxin. The fungus is localized in the endosperm and aleurone. To investigate the plant microbe interaction, we conducted histological and molecular studies to characterize the internal co...

  2. A quick SEED tutorial

    USGS Publications Warehouse

    Ringler, Adam; Evans, John R.

    2015-01-01

    A number of different government-funded seismic data centers offer free open-access data (e.g., U.S. Geological Survey, National Earthquake Information Center, the Incorporated Research Institutions for Seismology (IRIS), and Data Management System), which can be freely downloaded and shared among different members of the community (Lay, 2009). To efficiently share data, it is important that different data providers follow a common format. The Standard for the Exchange of Earthquake Data (SEED) provides one such format for storing seismic and other geophysical data. The SEED format is widely used in earthquake seismology; however, SEED and its structure can be difficult for many first-time users (ourselves included). Below is a quick tutorial that outlines the basic structure of SEED format. This write-up is in no way intended to replace the comprehensive SEED manual (Ahern et al., 2009), and instead of going into the details of any specific part of the SEED format we refer the reader to the manual for additional details. The goal of this write-up is to succinctly explain the basic structure of SEED format as well as the associated jargon, as most commonly used now, in a colloquial way so that novice users of SEED can become more familiar with the format and its application quickly. Our goal is to give the reader the necessary background so that when problems or questions about SEED format arise they will have some understanding of where they should look for more details or from where the problem might be stemming. As a secondary goal, we hope to help the reader become familiar with the SEED manual (Ahern et al., 2009), which contains detailed information about all aspects of the SEED format.

  3. Examining Children's Models of Seed.

    ERIC Educational Resources Information Center

    Jewell, Natalie

    2002-01-01

    Reports research that examines children's models of seed. Explores the conceptions held by children (N=75) of germination and seed formation. Concludes that children hold a restricted meaning for the term 'seed'. (DDR)

  4. Reduced availability of large seeds constrains Atlantic forest regeneration

    NASA Astrophysics Data System (ADS)

    Costa, Janaina B. P.; Melo, Felipe P. L.; Santos, Bráulio A.; Tabarelli, Marcelo

    2012-02-01

    Secondary forests are expanding in defaunated fragmented tropical landscapes, but their resilience potential remains poorly understood. In this study we used a chronosequence of advancing (19-62-yr old) Atlantic forest regeneration following slash-and-burn agriculture to infer successional shifts in seed rain in terms of seed density, species richness, taxonomic and functional composition, and local spatial distribution. After monitoring seed rain during 12 months in 60 1-m2 seed traps, we recorded over 400,000 seeds belonging to 180 morphospecies. From early to late-successional stage, seed rain decreased in density, increased in per capita species richness, gradually changed in species composition, and became less aggregated spatially. Regardless the age of forest stand, vertebrate-dispersed seeds accounted for 67-75% of all species recorded. Large-seeded species typical of old-growth forests, on the other hand, accounted for only 5-8% of the species recorded in the seed rain, a proportion around five times smaller than that reported for the old-growth forests of the same study site (31%). Our results suggest that the secondary forests considered, which are embedded in one of the largest (3500 ha) and best preserved remnant of the severely fragmented Atlantic forest of Northeast Brazil, may fail attaining older successional stages due to the reduced availability of large-seeded late-successional species. This regeneration constraint may be even stronger in smaller, more isolated forest remnants of the region, potentially reducing their ability to provide ecosystem services.

  5. Ultrasonic Detection and Imaging of Brachytherapy Seeds Based on Singular Spectrum Analysis

    NASA Astrophysics Data System (ADS)

    Mamou, J.; Feleppa, E. J.

    A commonly used, effective method of treating localized prostate cancer is implantation of small radioactive seeds. The standard imaging modality for treatment-planning dosimetry and for guiding and monitoring seed implantation is transrectal ultrasound (TRUS). However, movement of the prostate during seed insertion can cause seed misplacement, hemorrhage, and clutter from calcifications and other hyperechogenic scattering objects, and the specularity of seeds themselves make detecting seeds and verifying proper dosimetry difficult in an intraoperative time frame. Radiation oncologists would find a real-time imaging system that is capable of providing accurate, post-insertion, seed-location information to be very valuable because the information would enable timely feedback for intraoperatively correcting deficiencies in the radiation dose. Therefore, a remaining challenge for TRUS-guided brachytherapy of prostate cancer is accurate detection and localization of the seeds upon their insertion.

  6. Autoradiographic localization of mu and delta opioid receptors in the mesocorticolimbic dopamine system

    SciTech Connect

    Dilts, R.P. Jr.

    1989-01-01

    In vitro autoradiographic techniques were coupled with selective chemical lesions of the A10 dopamine cells and intrinsic perikarya of the region to delineate the anatomical localization of mu and delta opioid receptors, as well as, neurotensin receptors. Mu opioid receptors were labeled with {sup 125}I-DAGO. Delta receptors were labeled with {sup 125}I-DPDPE. Neurotensin receptors were labeled with {sup 125}I-NT3. Unilateral lesions of the dopamine perikarya were produced by injections of 6-OHDA administered in the ventral mesencephalon. Unilateral lesions of intrinsic perikarya were induced by injections of quinolinic acid in to the A10 dopamine cell region. Unilateral lesions produced with 6-OHDA resulted in the loss of neurotensin receptors in the A10 region and within the terminal fields. Mu opioid receptors were unaffected by this treatment, but delta opioid receptors increased in the contralateral striatum and nucleus accumbens following 6-OHDA administration. Quinolinic acid produced a reduction of mu opioid receptors within the A10 region with a concomitant reduction in neurotensin receptors in both the cell body region and terminal fields. These results are consistent with a variety of biochemical and behavioral data which suggest the indirect modulation of dopamine transmission by the opioids. In contrast these results strongly indicate a direct modulation of the mesolimbic dopamine system by neurotensin.

  7. Focal partial salvage low-dose-rate brachytherapy for local recurrent prostate cancer after permanent prostate brachytherapy with a review of the literature

    PubMed Central

    Wakumoto, Yoshiaki; Yamaguchi, Nanae; Horie, Shigeo; Sasai, Keisuke

    2016-01-01

    Purpose To investigate the treatment results for focal partial salvage re-implantation against local recurrence after permanent prostate brachytherapy. Material and methods Between January 2010 and September 2015, 12 patients were treated with focal partial salvage re-implantation for local recurrence after low-dose-rate brachytherapy using 125I seeds. The focal clinical target volume (F-CTV) was delineated on positive biopsy areas in a mapping biopsy, combining the cold spots on the post-implant dosimetry for initial brachytherapy. The F-CTV was expanded by 3 mm to create the planning target volume (PTV) as a margin to compensate for uncertainties in image registration and treatment delivery. The prescribed dose to the PTV was 145 Gy. The characteristics and biochemical disease-free survival (BdFS) rates were analyzed. Genitourinary (GU) and gastrointestinal (GI) toxicities were evaluated using the Common Terminology Criteria for Adverse Events version 4. Results The median prostate-specific antigen (PSA) level at re-implantation was 4.09 ng/ml (range: 2.91-8.24 ng/ml). The median follow-up time was 56 months (range: 6-74 months). The median RD2cc and UD10 were 63 Gy and 159 Gy, respectively. The 4-year BdFS rate was 78%, which included non-responders. Biochemical recurrence occurred in two patients after 7 and 31 months, respectively. The former was treated with hormonal therapy after biochemical failure, and the latter underwent watchful waiting (PSA at the last follow-up of 53 months: 7.3 ng/ml) at the patient's request. No patients had grade 3 GU/GI toxicities or died after salvage re-implantation. Conclusions The partial salvage low-dose-rate brachytherapy used to treat local recurrence after permanent prostate brachytherapy is well-tolerated, with high biochemical response rates. This treatment can be not only a method to delay chemical castration but also a curative treatment option in cases of local recurrence of prostate carcinoma after seed implantation

  8. Characterization and localization of nerve growth factor receptors in the embryonic otic vesicle and cochleovestibular ganglion

    SciTech Connect

    Bernd, P.; Represa, J. )

    1989-07-01

    We have investigated the possibility that nerve growth factor (NGF) may play a role in the development of the inner ear. Primordia of the inner ear, the otic vesicle (OV) and cochleovestibular ganglion (CVG), were isolated from 72-hr (stage 19-20) quail embryos and examined for the presence of NGF receptors. Quantitative binding studies revealed that both OV and CVG exhibited specific 125I-NGF binding; levels of nonspecific binding were 6 to 26% of total binding. Scatchard analysis yielded a linear plot, indicating the presence of a single class of NGF receptor. The average binding constant (Kd) was 8.0 nM for OV and 8.6 nM for CVG, corresponding to the low affinity (site II) NGF receptor. Examination of light microscopic radioautographs indicated that most of the specific 125I-NGF binding was located in the ventromedial wall of the OV, with little or no binding in the lateral wall and endolymphatic primordia. These studies were corroborated by microdissection of OV, in which 70% of the radioactivity was found to be localized in the medial half of the OV. In CVG, specific 125I-NGF binding was more concentrated in the cochlear portion of the ganglion, with silver grains primarily over areas containing support cells and immature neurons. Quantitative binding studies with isolated cochlear and vestibular ganglia obtained from 144-hr (stage 29-30) quail embryos revealed that the cochlear ganglion exhibited three times more specific 125I-NGF binding than the vestibular ganglion. The presence of NGF receptors on OV and CVG suggests that these structures are responsive to and/or dependent upon NGF. The following paper examines the question of whether NGF serves either as a mitogen, a survival factor, or a differentiation factor in this system.

  9. GROWING SEEDS, TEACHER'S GUIDE.

    ERIC Educational Resources Information Center

    Elementary Science Study, Newton, MA.

    THIS TEACHER'S GUIDE IS DESIGNED FOR USE WITH AN ELEMENTARY SCIENCE STUDY UNIT, "GROWING SEEDS," IN WHICH SUCH BASIC SCIENCE SKILLS AND PROCESSES AS MEASUREMENT, OBSERVATION, AND HYPOTHESIS FORMATION ARE INTRODUCED THROUGH STUDENT ACTIVITIES INVOLVING SEEDS, GERMINATION, AND SEEDLING GROWTH. THE MATERIALS WERE DEVELOPED FOR USE IN ELEMENTARY…

  10. [Quality classification criteria of Paeonia suffruticosa seeds].

    PubMed

    Cao, Ya-yue; Zhu, Zai-biao; Guo, Qiao-sheng; Liu, Li; Wang, Chang-lin

    2015-02-01

    In order to establish the quality classification criteria of Paeonia suffruticosa seeds, thirty-one batches of P. suffruticosa seeds from different provenances were selected. The seed rooting rate, seed germination rate, seed purity, seed viability, 1,000-seed weight and moisture content were determined and analyzed through SPSS 20.0 software. Seed rooting rate, seed germination rate and seed purity were selected as the main index for classification, while 1,000-seed weight, seed viability and moisture content could be used as important references. The seed quality grading of P. suffruticosa was set as three grades. The seed quality of each grade should meet following requirements: For the first grade seeds, seed rooting rate ≥ 80%, seed germination rate ≥ 80%, seed purity ≥ 90%, seed viability ≥ 80%, 1,000-seed weight ≥ 250 g, moisture content, ≤ 10. For the second grade seeds, seed rooting rate ≥ 50%, seed germination rate ≥ 60%, seed purity ≥ 70%, seed viability ≥ 75%, 1,000-seed weight ≥ 225 g, moisture content ≤ 10. For the third grade seeds, seed rooting rate ≥ 20%, seed germination rate ≥ 45%, seed purity ≥ 60%, seed viability ≥ 45%, 1,000-seed weight ≥ 205 g, moisture content ≤ 10. The quality classification criteria of P. suffruticosa seeds have been initially established.

  11. The earliest seeds

    USGS Publications Warehouse

    Gillespie, W.H.; Rothwell, G.W.; Scheckler, S.E.

    1981-01-01

    Lagenostomalean-type seeds in bifurcating cupule systems have been discovered in the late Devonian Hampshire Formation of Randolph County, West Virginia, USA (Fig. 1). The associated megaflora, plants from coal balls, and vertebrate and invertebrate faunas demonstrate that the material is Famennian; the microflora indicates a more specific Fa2c age. Consequently, these seeds predate Archaeosperma arnoldii1 from the Fa2d of northeastern Pennsylvania, the oldest previously reported seed. By applying precision fracture, transfer, de??gagement, and thin-section techniques to selected cupules from the more than 100 specimens on hand, we have determined the three-dimensional morphology and histology of the seeds (Fig. 2a-h, k) and cupule systems. A comparison with known late Devonian to early Carboniferous seeds reveals that ours are more primitively organized than all except Genomosperma2,3. ?? 1981 Nature Publishing Group.

  12. Seed supply for broadscale restoration: maximizing evolutionary potential

    PubMed Central

    Broadhurst, Linda M; Lowe, Andrew; Coates, David J; Cunningham, Saul A; McDonald, Maurice; Vesk, Peter A; Yates, Colin

    2008-01-01

    Restoring degraded land to combat environmental degradation requires the collection of vast quantities of germplasm (seed). Sourcing this material raises questions related to provenance selection, seed quality and harvest sustainability. Restoration guidelines strongly recommend using local sources to maximize local adaptation and prevent outbreeding depression, but in highly modified landscapes this restricts collection to small remnants where limited, poor quality seed is available, and where harvesting impacts may be high. We review three principles guiding the sourcing of restoration germplasm: (i) the appropriateness of using ‘local’ seed, (ii) sample sizes and population characteristics required to capture sufficient genetic diversity to establish self-sustaining populations and (iii) the impact of over-harvesting source populations. We review these topics by examining current collection guidelines and the evidence supporting these, then we consider if the guidelines can be improved and the consequences of not doing so. We find that the emphasis on local seed sourcing will, in many cases, lead to poor restoration outcomes, particularly at broad geographic scales. We suggest that seed sourcing should concentrate less on local collection and more on capturing high quality and genetically diverse seed to maximize the adaptive potential of restoration efforts to current and future environmental change. PMID:25567799

  13. Magnetic stimulation of marigold seed

    NASA Astrophysics Data System (ADS)

    Afzal, I.; Mukhtar, K.; Qasim, M.; Basra, S. M. A.; Shahid, M.; Haq, Z.

    2012-10-01

    The effects of magnetic field treatments of French marigold seeds on germination, early seedling growth and biochemical changes of seedlings were studied under controlled conditions. For this purpose, seeds were exposed to five different magnetic seed treatments