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91.
Tsunehiko Nishimura Hisashi Oka Masatsugo Sago Takeshi Matsuo Toshiisa Uehara Hiroyuki Nodal Hisateru Takano 《European journal of nuclear medicine and molecular imaging》1992,19(1):25-29
Iodine-123 metaiodobenzylguanidine (mIBG) is taken up by sympathetic nerve endings, allowing scintigraphic imaging of myocardial sympathetic innervation. We investigated the denervated but viable canine myocardium after acute myocardial infarction by serial mIBG and thallium-201 chloride (201TIC1) single photon emission tomography (SPET). In 12 dogs, acute myocardial infarction was produced by ligation of the left circumflex coronary artery. Images of mIBG and thallium SPET were obtained 6 h, 1, 4 and 6 weeks later. The defect size was calculated in percentage points from short axial views, and the 123I-mIBG/201TlCl ratio was determined. The uptake ratio was high at 1 week but gradually decreased. Three dogs were killed at each time point, and tissue samples were obtained from infarcted (both 201TICl and 123I-mIBG defects), peri-infarcted (123I-mIBG defect and 201TICl normal) and normal myocardium (both mIBG and 201TIC1 normal). The changes in tissue content of noradrenaline in these lesions were measured. Noradrenaline tissue content gradually recovered in the peri-infarcted area. However, no recovery was noted in the infarcted area at 6 weeks. We conclude that sympathetic denervation and re-innervation occur following acute myocardial infarction, and the denervated but viable myocardium could be detected non-invasively by combined mIBG and thallium SPET.
Offprint requests to: T. Nishimura 相似文献
92.
Nicolaas P. L. G. Verhoeff Ellinor Busemann Sokole Michael Stabin Daan Hengst Hank F. Kung Eric A. Van Royen Antonius G. M. Janssen 《European journal of nuclear medicine and molecular imaging》1993,20(9):747-752
The distribution of the dopamine D2-receptor specific ligand iodine-123 (S)-(–)-2-hydroxy-3-iodo-6-methoxy-N[(1-ethyl-2-pyrrolidinyl)methyl]-benzamide (1231-IBZM) was investigated in human adults from whole-body scans, blood samples and urine collected up to 48 h after injection. Results from the present study performed in six healthy volunteers were combined with those of five volunteers from a previous study. Using the brain, liver, lungs and spleen as source organs, the MIRD method was applied to calculate the absorbed radiation dose of the radioligand in various organs. The thyroid (despite blockage), gall-bladder wall, large intestinal walls and spleen received the highest absorbed doses. The average effective dose equivalent of 123I-IBZM for adults was estimated to be 0.034 mSv/MBq. The absorbed dose to the thyroid may be a limiting factor for 1231-IBZM studies in children. 相似文献
93.
Translocations of chromosomes occurring in human cancer cells appear specific to the type of cell from which the cancer arises. To explain the action of these translocations, we propose dual position effect: Position effect of the cis type transforms the cell to malignancy, while position effect of the trans type permits the normal homologous chromosome to express a normal gene product. Thus, the translocation itself has to do with malignant transformation, while the normal homologous chromosome performs its normal function. This dual concept is illustrated by t(8;14) in Burkitt's lymphoma. The concept can be tested with t(2;18) and t(8;22) in lymphoid malignancies and with other translocations and chromosome rearrangements marking human cancer cells. 相似文献
94.
Acute urinary morbidity following I-125 prostate brachytherapy 总被引:1,自引:0,他引:1
Ohashi T Yorozu A Toya K Saito S Momma T 《International journal of clinical oncology / Japan Society of Clinical Oncology》2005,10(4):262-268
Background In Japan, iodine-125 (I-125) prostate brachytherapy has been legally approved since July 2003, and this method is becoming more popular. The purpose of the present study was to assess acute urinary morbidity within the first 6 months after I-125 prostate brachytherapy.Methods A group of 130 consecutive patients with loca-lized prostate cancer was treated with I-125 prostate brachytherapy between September 2003 and June 2004,either alone (monotherapy; 66 patients) or in combination with external-beam radiotherapy (combined therapy; 64 patients). Urinary morbidity was evaluated using the National Cancer Institute – Common Terminology Criteria for Adverse Events, version 3.0.Results During the follow-up, 111 patients (85.4%) developed some degree of urinary symptoms such as frequency, retention, dysuria, incontinence, or hematuria. Urinaryfrequency (73.1%) and retention (66.9%) were the most common, and showed no significant differences between the monotherapy group and combined therapy group (P = 0.352 and P = 0.630, respectively). Six patients (4.6%) required catheterization for urinary obstruction; the median timeto onset was 1.5 days (range, 1–192 days). Five of these6 patients received monotherapy and the other received combined therapy.Conclusion Manifestations of acute urinary morbidity, especially frequency and retention, are relatively common but acceptable events after I-125 prostate brachytherapy. 相似文献
95.
Nikolaus S Wirrwar A Antke C Arkian S Schramm N Müller HW Larisch R 《European journal of nuclear medicine and molecular imaging》2005,32(3):308-313
Purpose The aim of this study was to investigate the feasibility of assessing dopamine transporter binding after treatment with methylphenidate in the rat using a recently developed high-resolution small animal single-photon emission computed tomograph (TierSPECT) and [123I]FP-CIT.Methods [123I]FP-CIT was administered intravenously 1 h after intraperitoneal injection of methylphenidate (10 mg/kg) or vehicle. Animals underwent scanning 2 h after radioligand administration. The striatum was identified by superimposition of [123I]FP-CIT scans with bone metabolism and perfusion scans obtained with 99mTc-DPD and 99mTc-tetrofosmin, respectively. As these tracers do not pass the blood–brain barrier, their distribution permits the identification of extracerebral anatomical landmarks such as the orbitae and the harderian glands. The cerebellum was identified by superimposing [123I]FP-CIT scans with images of brain perfusion obtained with 99mTc-HMPAO.Results Methylphenidate-treated animals and vehicle-treated animals yielded striatal equilibrium ratios (V3) of 0.24±0.26 (mean ± SD) and 1.09±0.42, respectively (t test, two-tailed, p<0.0001). Cortical V3 values amounted to 0.05±0.28 (methylphenidate) and 0.3±0.39 (saline, p=0.176). This first in vivo study of rat dopamine transporter binding after pre-treatment with methylphenidate showed a mean reduction of 78% in striatal [123I]FP-CIT accumulation.Conclusion The results can be interpreted in terms of a pharmacological blockade in the rat striatum and show that in vivo quantitation of dopamine transporter binding is feasible with [123I]FP-CIT and the TierSPECT. This may be of future relevance for in vivo investigations on rat models of attention deficit/hyperactivity disorder. Furthermore, our findings suggest that investigations in other animal models, e.g. of Parkinsons and Huntingtons disease, may be feasible using SPECT radioligands and small animal imaging systems. 相似文献
96.
Lambert B Van de Wiele C 《European journal of nuclear medicine and molecular imaging》2005,32(8):980-989
Several techniques have been developed for radionuclide therapy of hepatocellular carcinoma (HCC). Medical literature databases (Pubmed, Medline) were screened for available literature and articles were critically analysed as to their scientific relevance. In a palliative setting, intra-arterial administration of 131I-Lipiodol yields responses in 17–92% of patients. According to a randomised study, 131I-Lipiodol was far better tolerated than classic chemo-embolisation. The additive value of a single 131I-Lipiodol administration following partial liver resection for HCC was evaluated and evidence is available that adjuvant radionuclide treatment reduces the recurrence rate. Data concerning the role of 131I-Lipiodol in bridging patient to liver transplantation are scarce but suggest a potential benefit in terms of reducing the drop-out rate while patients are listed for transplantation. 188Re- and 90Y-labelled conjugates are emerging and initial clinical data are promising. Treatment of HCC with 90Y-labelled microspheres is likely as efficacious as treatment with radiolabelled Lipiodol but pretreatment 99mTc-MAA scintigraphy is required in order to exclude patients with significant lung shunting. Several antibodies targeting antigens expressed on HCC have been radiolabelled, almost exclusively with 131I, and evaluated in a preclinical or clinical setting. The use of radiolabelled Lipiodol and microspheres allows for selective targeting of HCC with limited toxicity. Prospective, randomised controlled trials demonstrating that both treatment modalities may provide a survival benefit in a palliative setting are mandatory. In addition, future research should focus on the complementary role of radionuclide treatment in patients at risk for recurrent disease following partial liver resection or while awaiting liver transplantation. 相似文献
97.
Erlandsson K Sivananthan T Lui D Spezzi A Townsend CE Mu S Lucas R Warrington S Ell PJ 《European journal of nuclear medicine and molecular imaging》2005,32(11):1329-1336
Purpose Serotonergic brain regions play a crucial role in the modulation of emotion, and serotonergic dysfunction may contribute to several neurological disorders. [123I]ADAM is a novel SPECT tracer which binds with high affinity to serotonin transporters (SERT). The objective of this study was to compare different methods for the quantification of tracer binding and to develop a simplified single-scan protocol for this tracer, as well as to investigate its potential for characterisation of the transporter occupancy versus plasma concentration curve of a selective serotonin re-uptake inhibitor (SSRI).Methods Dynamic SPECT scans were performed on 16 healthy volunteers after administration of 150 MBq [123I]ADAM. Data were acquired from the time of injection until 5.5 h after injection in 30- or 45-min sessions. Each subject was scanned twice: with and without pre-treatment with the SSRI citalopram in various dosage regimens. The plasma concentration of citalopram (Cp) was determined from venous samples. Images were reconstructed by filtered back-projection with scatter and attenuation correction. Tracer binding was quantified for midbrain, striatum and thalamus using cerebellum as a reference region. Quantification was done by kinetic modelling, graphical analysis and multi-linear regression, as well as by the ratio method, with binding potential (BP2) as the outcome measure. The SERT occupancy by citalopram was determined relative to the baseline scan for each subject, and the occupancy versus Cp curve was fitted with the Emax model.Results The highest binding of [123I]ADAM was in midbrain (mean baseline BP2±SD=1.31±0.29), with lower binding in thalamus (0.79±0.16) and striatum (0.66±0.13). There was good agreement between BP2 values obtained by different quantification methods. Using the ratio method, the best agreement with kinetic modelling was obtained with data from the time interval [200,260] min after injection. The fitting of the midbrain occupancy curve yielded a maximum occupancy of 84% and a plasma concentration required to reach 50% of the maximum of 2.5 ng/ml, with a goodness-of-fit variability of 13% (SD).Conclusion Binding of [123I]ADAM to SERT in midbrain can be quantified with a single scan starting 200 min after injection. However, the variability of estimated occupancy values may be too high for critical assessment of occupancy of SERT by SSRI. 相似文献
98.
Lilia Curzi-Dascalova Claude Gaudebout Colette Dreyfus-Brisac 《Early human development》1981,5(1):39-54
This study was carried out on 57 normal infants: 22 full-term newborns, examined in the hospital laboratory, and 35 2–18-wk-old infants, examined in two resident nurseries. Polygraphic records, including 1–3 complete sleep cycles, were performed during the morning. The tracings were analyzed by 20-sec epochs.Three to 10% of active sleep states (AS) and 0.8-4% of quiet sleep states (QS) included ?3 sec respiratory pauses. There were minimal, non-significant differences between respiratory frequencies (RF) in total and in no-pause tracings.Our results confirmed that RF was higher in AS in all ages, when compared with QS (P < 0.02). During the transition (TS) from one to another well-defined sleep state, the respiratory rate showed an intermediate level (AS > TS > QS): the transition from AS to QS showed progressive slowing of RF, while the transition from QS to AS occurred abruptly, with sudden acceleration of RF. There was a significant slowing of RF during the course of QS, while the RF in AS was more variable without significant differences between the beginning, the middle and the end of AS state. In this material, RF was higher in 2–5-wk and 6–10-wk age groups, compared to newborns and to 11-18-wk-old infants. At all ages, there was a high degree of correlation (P < 0.01) between RF found in different sleep states for given individuals: some infants breathed more rapidly and others more slowly in all sleep states.A review of the literature showed that the differences between normal RF 相似文献
99.
Imaging of dopamine transporters and D2 receptors in vascular parkinsonism: a report of four cases 总被引:1,自引:0,他引:1
Plotkin M Amthauer H Quill S Marzinzik F Klostermann F Klaffke S Kivi A Gutberlet M Felix R Kupsch A 《Journal of neural transmission (Vienna, Austria : 1996)》2005,112(10):1355-1361
Summary. The role of nuclear medicine imaging in the diagnosis of vascular parkinsonism (VP) has been addressed by only few studies
up to now. Most previous reports suggest no or only mild impairment of DAT and D2 receptors in VP. In contrast, in four patients
with VP, reported here, the combined DAT and D2 receptor SPECT showed highly unusual changes in the pre- and/or postsynaptic
dopaminergic system. The possible value of combined DAT/D2 receptor SPECT imaging should be investigated by future prospective
studies.
These two authors contributed equally 相似文献
100.
Plotkin M Amthauer H Eisenacher J Wurm R Michel R Wust P Stockhammer F Röttgen R Gutberlet M Ruf J Felix R 《Neuroradiology》2005,47(1):18-26
The value of single-photon emission tomography (SPECT) using iodine-123-alpha-methyl-tyrosine (IMT) for the diagnosis of recurrent or residual gliomas is well established. In the current study we investigated whether IMT-SPECT could also be useful in the follow-up of brain metastases and other intracranial tumours of non-astrocytic origin. The study included 22 patients with suspected recurrent intracranial tumours of non-astrocytic origin (12 brain metastases, one supratentorial primitive neuroendocrine tumour (PNET), one rhabdoid tumour, two clivus chordomas, three ependymomas, two pituitary tumours, one anaplastic meningioma) who had previously been treated by surgery and/or radio/chemotherapy. SPECT results were correlated with clinical and MRI follow-up data. The study was true positive in 13 patients, true negative in five, false positive in one and false negative in three patients. Notably, all false negative findings were <13 mm. The resulting sensitivity of the IMT-SPECT was 81%. We concluded that the IMT-SPECT is a promising complementary imaging tool for the detection of recurrences of non-astrocytic intracranial tumours and their distinguishing from treatment-induced changes. The limitation of the IMT-SPECT is its low sensitivity for the detection of small lesions. 相似文献