共查询到20条相似文献,搜索用时 15 毫秒
1.
《International journal of radiation applications and instrumentation. Part B, Nuclear medicine and biology》1986,13(3):253-255
67Ga citrate and 99mTc citrate (Solcocitran) were injected sequentially, with an interval of 48 h, into Balb/c mice bearing transplanted EMT-6 tumors. Tissue distributions of 67Ga and 99mTe were measured simultaneously at intervals of 1, 3, 5 and 8 h after injection of the 99mTc citrate (49, 51, 53 and 56 h after 67Ga citrate). Maximal tumor:blood ratios for 99mGa and 99mTc were 13.8 ± 3.2 and 4.0 ± 1.0 respectively, both occurring at the final period. The maximum tumor index (T.I. = T:B x % dose/g) for 67Ga was 71 ± 23% 56 h after injection, and for Tc was 13 ± 12% 1 h after injection. Liver, kidney and spleen had equal or higher concentrations of radioactivity than tumor for either radiotracer. The somewhat higher tumor:blood ratio for 67Ga citrate was offset by the time required for this optimum to be reached. Alternatively, the best 99mTc citrate tumor:blood ratios were attained within 8 h, with less liver and gut radioactivity. These data fall within the range of results from other clinical and animal model studies of 67Ga citrate and Tc citrate. In view of the radiation dose, the inconvenience of the 48–72 h wait, and the cost of 67Ga, and because neither radiopharmaceutical is tumor specific, 99mTc citrate may have a place in early oncological screening. The results are discussed as part of a comprehensive review of the 99mTc citrate literature. 相似文献
2.
《International journal of radiation applications and instrumentation. Part B, Nuclear medicine and biology》1992,19(1):79-81
Red blood cells were labelled with 67Ga oxine prepared from 67Ga citrate, a routinely available and relatively inexpensive radiopharmaceutical which is suitable for dual-isotope imaging with 99mTc. Labelling efficiency was 88 ± 1%, 24-h in vitro stability was 93 ± 5% in saline at room temperature and 68 ± 4% in whole blood at 37 °C, and the method could be performed within 20–30 min. 相似文献
3.
《International journal of radiation applications and instrumentation. Part B, Nuclear medicine and biology》1992,19(5):539-547
A new method for labeling preformed liposomes with technetium-99m (99mTc) has been developed which is simple to perform and stable in vivo. Previous 99mTc-liposome labels have had variable labeling efficiencies and stability. This method consistently achieves high labeling efficiencies (> 90%) with excellent stability. A commercially available radiopharmaceutical kit—hexamethylpropyleneamine oxime (HM-PAO)—is reconstituted with 99mTcO−4 and then incubated with preformed liposomes that encapsulate glutathione. The incubation takes only 30 min at room temperature. Liposomes that co-encapsulate other proteins such as hemoglobin or albumin, in addition to glutathione, also label with high efficiency. Both in vitro and in vivo studies indicate good stability of this label. Rabbit images show significant spleen and liver uptake at 2 and 20 h after liposome infusion without visualization of thyroid, stomach or bladder activity.This labeling method can be used to study the biodistribution of a wide variety of liposome preparations that are being tested as novel drug delivery systems. This method of labeling liposomes with 99mTc may also have applications in diagnostic imaging. 相似文献
4.
《International journal of radiation applications and instrumentation. Part B, Nuclear medicine and biology》1991,18(5):461-468
Platelets pretinned with a neutral Sn(II)-2-mercaptopyridme-N-oxide (SN-MPO) were labeled with 99mTc and compared to those labeled with 99mTc-HMPAO. The conditions of labeling platelets, e.g. concentrations of platelets and Sn(II)-MPO, 99mTc in ACD-saline or ACD-plasma media, pH and incubation time, were optimized using canine platelets. Moderate labeling efficiency was obtained with 20 μg of tin(II) chloride and 30 min incubation with Sn-MPO and pertechnetate. The viability of labeled platelets was determined by platelet recovery and platelet survival times in Beagle dogs. The labeling efficiency with platelets from 43 mL of blood was 62.8 ± 7.6%. The platelet recovery was 35.7 ± 5.0% and exponential survival time was 34.6 ± 3.1 h compared to 43.3 ± 12.0% and 29.5 ± 3.3 h for 99mTc-HMPAO-labeled platelets. These values were significantly (P < 0.01) lower than 111In-labeled platelets. Biodistribution in dogs indicates lower retention in blood, spleen and liver after some initial 99mTc excretion in urine. The platelet deposition with 99mTc platelets (Sn-MPO method) on polyurethane angio-catheters was similar to 99mTc-HMPAO-labeled platelets. This study indicates that the platelets could be successfully labeled with pertechnetate in a cost-effective manner for the evaluation of thromboembolic complications. 相似文献
5.
Muhammad Usman Akbar Tanveer Hussain Bokhari Samina Roohi Khalid Mahmood Zia Mohammad Zuber Nadia Parveen Narmeen Ali 《Russian Journal of Bioorganic Chemistry》2016,42(5):491-496
Human biosynthetic insulin is a polypeptide hormone that plays an important and essential role in control of the level of carbohydrate, protein, and fat metabolism in the blood. Human pancreatic insulin was labeled with 99mTc to form a new radiopharmaceutical with a labeling yield of 99 ± 1% under optimum conditions: 0.1 mL insulin, pH 7, 25 μg stannous chloride, 1 mL (19 mCi) of pertechnetate, room temperature, and 10 min reaction time. The 99mTc–insulin complex was examined using paper chromatography, ITLC, electrophoresis, and HPLC. In addition, in vitro and in vivo study of 99mTc–insulin complex was performed at different time intervals. 相似文献
6.
《International journal of radiation applications and instrumentation. Part B, Nuclear medicine and biology》1991,18(7):769-775
A triphenylethylene compound [1,1-bis(4-hydroxyphenyl)-2-iodo-2-phenylethylene; IBHPE]has been labeled by halodestannylation with 12.I at a specific radioactivity of 13,200 Ci/mmol (by in vitro receptor assay) after HPLC purification. The corresponding 80mBr-labeled compound (BrBHPE), which has a 3-fold higher affinity for the estrogen receptor, was previously prepared and examined as a potential therapeutic radiopharmaceutical exploiting Auger electron toxicity. Stability of IBHPE was a concern because free iodide was generated when HPLC solvents were removed with a stream of nitrogen in a glass vial; however, decomposition was minimal when polypropylene vials were used, and ethanol solutions of [123I]IBHPE were stable for several days at 0–4 °C. Tissue distribution studies of IBHPE after intraperitoneal injection to mature female rats showed highest estradiol-inhibitable uptake in the peritoneal estrogen-receptor rich tissues (uterus, ovaries and vagina) at 30 min. Specific uptake (percent dose per gram) in the pituitary, and peritoneal target tissue-to-blood ratios were greater at 2 h than 30 min. In immature female rats, uterus-to-blood ratios of > 50, progressively lowered by increasing diethylstilbestrol levels, were obtained. These data demonstrate good binding of IBHPE to the estrogen receptor in vivo, in spite of extensive non specific binding in in vitro estrogen receptor assays. Most of the label in the uterus at 1 h after injection was still unchanged IBHPE. Our results suggest that IBHPE or related 123I-labeled iodovinyl triphenylethylenes could have diagnostic or therapeutic radiopharmaceutical utility. 相似文献
7.
Xin Chen Meng-Chao Cui Winnie Deuther-Conrad Ying-Feng Tu Teng Ma Ying Xie Bing Jia Yan Li Fang Xie Xia Wang Jörg Steinbach Peter Brust Bo-Li Liu Hong-Mei Jia 《Bioorganic & medicinal chemistry letters》2012,22(20):6352-6357
We report the design, synthesis and biological evaluation of a novel 99mTc 4-(4-cyclohexylpiperazine-1-yl)-butan-1-one-1-cyclopentadienyltricarbonyl technetium ([99mTc]5) as a potential SPECT tracer for imaging of σ2 receptors in tumors. [99mTc]5 was prepared in 25 ± 5% isolated radiochemical yield with radiochemical purity of >99% via double-ligand transfer (DLT) reaction from the ferrocene precursor 2b (4-(4-cyclohexylpiperazine-1-yl)-1-ferrocenylbutan-1-one). The corresponding Re-complex 4 and the ferrocenyl complex 2b showed relatively high affinity towards σ2 receptors in in vitro competition binding assay (Ki values of 4 and 2b were 64.4 ± 18.5 nM and 43.6 ± 21.3 nM, respectively) and moderate to high selectivity versus σ1 receptors (Kiσ1/Kiσ2 ratios were 12.5 and 95.5, respectively). The log D value of [99mTc]5 was determined to be 2.52 ± 0.33. Biodistribution studies in mice revealed comparably high initial brain uptake of [99mTc]5 and slow washout. Administration of haloperidol 5 min prior to injection of [99mTc]5 significantly reduced the radiotracer uptake in brain, heart, lung, and spleen by 40–50% at 2 h p.i.. Moreover, [99mTc]5 showed high uptake in C6 glioma cell lines (8.6%) after incubation for 1 h. Blocking with haloperidol to compete with [99mTc]5 significantly reduced the cell uptake. Preliminary blocking study in C6-brain-tumor bearing rats showed that [99mTc]5 binds to σ receptors in the brain-tumor specifically. These results are encouraging for further exploration of 99mTc-labeled probes for σ2 receptor tumor imaging in vivo. 相似文献
8.
《International journal of radiation applications and instrumentation. Part B, Nuclear medicine and biology》1991,18(2):227-233
We have evaluated five compounds, stannous chloride (SnCl2), 2-mercaptoethanol (2-ME), dithiothreitol (DTT), dithioerythritol (DTE), and ascorbic acid (AA) to reduce monoclonal antibody MoAb (disulfide groups and compared their efficacy for labeling MoAbs with 99mTc. The reduction of 99mTc with dithionite at pH 11 was nearly quantitative. The use of AA, at a molar ratio of 3500:1, for three IgG and three IgM antibodies examined, gave a labeling efficiency greater than 95%. Hence no purification was needed. The immunospecificity of AA preparations determined by specific antigen assay was 84 ± 1% for an IgM and 82.6 ± 1.1% for an IgG, highest among all agents tested. The stability of the tracer was evaluated by challenging the product with such 99mTc avid agents as cysteine, DTPA, and human serum albumin. By HPLC analysis, no 99mTc was transchelated using chelating agent to protein molar ratios as high as 500:1. In two separate groups of five mice each, the liver uptake at 4 h post injection averaged 6.8 ± 2.9% per gram for 125I-TNT-1 (IgG) and 6 ± 5.1% per gram for the same MoAb labeled with 99mTc using AA. The AA technique promises to label antibodies with 99mTc and perhaps with 186Re, by a simple “kit” procedure. 相似文献
9.
This study presents current status of performance of radiopharmaceutical activity measurements using radionuclide calibrators in Belgium. An intercomparison exercise was performed among 15 hospitals to test the accuracy of 99mTc, 18F and 111In activity measurements by means of radionuclide calibrators. Four sessions were held in different geographical regions between December 2013 and February 2015. The data set includes measurements from 38 calibrators, yielding 36 calibrations for 99mTc and 111In, and 21 calibrations for 18F. For each radionuclide, 3 ml of stock solution was measured in two clinical geometries: a 10 ml glass vial and a 10 ml syringe. The initial activity was typically 100 MBq for 99mTc, 15 MBq for 111In and 115 MBq for 18F. The reference value for the massic activity of the radioactive solutions was determined by means of primary and secondary standardisation techniques at the radionuclide metrology laboratory of the JRC.The overall results of the intercomparison were satisfactory for 99mTc and 18F, since most radionuclide calibrators (>70%) were accurate within ±5% of the reference value. Nevertheless, some devices underestimated the activity by 10–20%. Conversely, 111In measurements were strongly affected by source geometry effects and this had a negative impact on the accuracy of the measurements, in particular for the syringe sample. Large overestimations (up to 72%) were observed, even when taking into account the corrections and uncertainties supplied by the manufacturers for container effects. The results of this exercise encourage the hospitals to perform corrective actions to improve the calibration of their devices where needed. 相似文献
10.
Jianquan Yang Haixun Guo R. Steve Padilla Marianne Berwick Yubin Miao 《Bioorganic & medicinal chemistry》2010,18(18):6695-6700
The purpose of this study was to reduce the non-specific renal uptake of Arg-Gly-Asp (RGD)-conjugated alpha-melanocyte stimulating hormone (α-MSH) hybrid peptide through structural modification or l-lysine co-injection. The RGD motif {cyclic(Arg-Gly-Asp-DTyr-Asp)} was coupled to [Cys3,4,10, d-Phe7, Arg11] α-MSH3-13 {(Arg11)CCMSH} through the Arg linker (substituting the Lys linker) to generate a novel RGD-Arg-(Arg11)CCMSH hybrid peptide. The melanoma targeting and pharmacokinetic properties of 99mTc-RGD-Arg-(Arg11)CCMSH were determined in B16/F1 melanoma-bearing C57 mice. The effect of l-lysine co-injection on the renal uptake was determined through the co-injection of l-lysine with 99mTc-RGD-Arg-(Arg11)CCMSH or 99mTc-RGD-Lys-(Arg11)CCMSH. Replacement of the Lys linker with an Arg linker exhibited a profound effect in reducing the non-specific renal uptake of 99mTc-RGD-Arg-(Arg11)CCMSH, as well as increasing the tumor uptake of 99mTc-RGD-Arg-(Arg11)CCMSH compared to 99mTc-RGD-Lys-(Arg11)CCMSH. 99mTc-RGD-Arg-(Arg11)CCMSH exhibited high tumor uptake (21.41 ± 3.74% ID/g at 2 h post-injection) and prolonged tumor retention (6.81 ± 3.71% ID/g at 24 h post-injection) in B16/F1 melanoma-bearing mice. The renal uptake values of 99mTc-RGD-Arg-(Arg11)CCMSH were 40.14–64.08% of those of 99mTc-RGD-Lys-(Arg11)CCMSH (p <0.05) at 0.5, 2, 4 and 24 h post-injection. Co-injection of l-lysine was effective in decreasing the renal uptakes of 99mTc-RGD-Arg-(Arg11)CCMSH by 27.7% and 99mTc-RGD-Lys-(Arg11)CCMSH by 52.1% at 2 h post-injection. Substitution of the Lys linker with an Arg linker dramatically improved the melanoma uptake and reduced the renal uptake of 99mTc-RGD-Arg-(Arg11)CCMSH, warranting the further evaluation of 188Re-labeled RGD-Arg-(Arg11)CCMSH as a novel MC1 receptor-targeting therapeutic peptide for melanoma treatment in the future. 相似文献
11.
Chemical fertilizer agricultural wastewater is a typical high-strength wastewater that has dramatically triggered numerous environmental problems in China. The Chlorella vulgaris microalgae biological wastewater treatment system used in this study can effectively decontaminate the high-strength carbon and nitrogen wastewater under an optimum light wavelength and light intensity supply strategy. The descending order of both the dry weight for C. vulgaris reproduction and wastewater nutrient removal efficiency is red > white > yellow > purple > blue > green, which indicates that red light is the optimum light wavelength. Furthermore, rather than constant light, optimal light intensity is used for the incremental light intensity strategy. The phases for the optimal light intensity supply strategy are as follows: Phase 1 from 0 to 48 h at 800 μmol m?2 s?1; Phase 2 from 48 to 96 h at 1,200 μmol m?2 s?1; and Phase 3 from 96 to 144 h at 1,600 μmol m?2 s?1. Additionally, the optimal cultivation time is 144 h. 相似文献
12.
《International journal of radiation applications and instrumentation. Part B, Nuclear medicine and biology》1992,19(3):251-256
A simplified and efficient procedure for 99mTc-HMPAO-labelling of leukocytes is described. For this purpose, the pH and concentration of the 99mTc-HMPAO preparation was modified. Leukocytes were isolated from a 20 mL mixture of patient blood, 5 mL ACD and 0.8 mL methylcellulose after 1 h sedimentation of erythrocytes and centrifugation (at 400 g) of the obtained plasma layer. Simultaneously, 99mTc-HMPAO was prepared (one single-dose kit for two patients) by adding 2.2 mL 99mTc-generator eluate and, after 10 min, 0.3 mL of phosphate buffer to lower the pH to 7. The isolated WBCs were then labelled by the addition of 1-1.2 mL of 99mTc-HMPAO solution and incubated for 20 min. The unbound tracer was then discarded, the labelled WBC washed and finally resuspended in autologous cell-free plasma. Leukocytes labelled by this procedure were used for scintigraphic localization of inflammatory lesions and abscesses in the gastro-intestinal tract.The labelling efficiency was 60 ± 9%, with a separation yield of 55 ± 11%. 相似文献
13.
Kakali De Arijit Bhowmik Ashok Behera Indranil Banerjee Mrinal Kanti Ghosh Mridula Misra 《Journal of peptide science》2012,18(12):720-730
Radiolabeled somatostatin analogs have become powerful tools in the diagnosis and staging of neuroendocrine tumors, which express somatostatin receptors. The aim of this study was to evaluate a new somatostatin analog, 6‐hydrazinopyridine‐3‐carboxylic acid‐Ser3‐octreotate (HYNIC‐SATE) radiolabeled with 99mTc, using ethylenediamine‐N,N′‐diacetic acid and tricine as coligands, to be used as a radiopharmaceutical for the in vivo imaging of somatostatin receptor subtype 2 (SSTR2)‐positive tumor. Synthesis of the peptide was carried out on a solid phase using a standard Fmoc strategy. Peptide conjugate affinities for SSTR2 were determined by receptor binding affinity on rat brain cortex and C6 cell membranes. Internalization rate of 99mTc‐HYNIC‐SATE was studied in SSTR2‐expressing C6 cells that were used for intracranial tumor studies in rat brain. A reproducible in vivo C6 glioma model was developed in Sprague–Dawley rat and confirmed by histopathology and immunohistochemical analysis. Biodistribution and imaging properties of this new radiopeptide were also studied in C6 tumor‐bearing rats. Radiolabeling was performed at high specific activities, with a radiochemical purity of >96%. Peptide conjugate showed high affinity binding for SSTR2 (HYNIC‐SATE IC50 = 1.60 ± 0.05 n m ) and specific internalization into rat C6 cells. After administration of 99mTc‐HYNIC‐SATE in C6 glioma‐bearing rats, a receptor specific uptake of radioactivity was observed in SSTR‐positive organs and in the implanted intracranial tumor and rapid excretion from nontarget tissues via kidneys. 99mTc‐HYNIC‐SATE is a new receptor‐specific radiopeptide for targeting SSTR2‐positive brain tumor and might be of great promise in the scintigraphy of SSTR2‐positive tumors. Copyright © 2012 European Peptide Society and John Wiley & Sons, Ltd. 相似文献
14.
Meng-zhi Zhang Yan-xing Guan Jin-xiu Zhong Xue-zhong Chen 《Translational oncology》2017,10(4):518-526
OBJECTIVE: A micro-molecule peptide TP1623 of 99mTc-human epithelial growth factor receptor 2 (HER2) was prepared and the feasibility of using it as a HER2-positive molecular imaging agent for breast cancer was evaluated. METHODS: TP1623 was chemically synthesized and labeled with 99mTc. The labeling ratio and stability were detected. HER2 expression levels of breast cancer cells (SKBR3 and MDA-MB-231) and cell binding activity were measured. Biodistribution of 99mTC-TP1623 in normal mice was detected. SKBR3/MDA-MB-231-bearing nude mice models with high/low expressions of HER2 were established. Tumor tissues were stained with hematoxylin–eosin (HE) and measured by immunohistochemistry to confirm the formation of tumors and HER2 expression. SPECT imaging was conducted for HER2-overexpressing SKBR3-bearing nude mice. The T/NT ratio was calculated and compared with that of MDA-MB-231-bearing nude mice with low HER2 expression. The competitive inhibition image was used to discuss the specific binding of 99mTc- TP1623 and the tumor. RESULTS: The labeling ratio of 99mTc-TP1623, specific activity, and radiochemical purity (RCP) after 6 h at room temperature were (97.39 ± 0.23)%, (24.61 ± 0.06) TBq/mmol, and (93.25 ± 0.06)%, respectively. HER2 of SKBR3 and MDA-MB-231 cells showed high and low expression levels by immunohistochemistry, respectively. The in vitro receptor assays indicated that specific binding of TP1623 and HER2 was retained. Radioactivity in the brain was always at the lowest level, while the clearance rate of blood and the excretion rate of the kidneys were fast. HE staining showed that tumor cells were observed in SKBR3- and MDA-MB-231-bearing nude mice, with significant heteromorphism and increased mitotic count. The imaging of mice showed that targeted images could be made of 99mTc-TP1623 in high HER2-expressing tumors, while no obvious development was shown in tumors in low HER2-expressing nude mice. No development was visible in tumors in competitive inhibition of imaging, which indicates the combination of 99mTc-TP1623 and tumor was mediated by HER2. CONCLUSION: High labeling ratio and specific activity of 99mTc-TP1623 is successfully prepared; it is a molecular imaging agent for HER2-positive tumors that has potential applicative value. 相似文献
15.
Evaluation of the performance of structured mixed packing and inert packing materials in toluene biotrickle-filtration 总被引:1,自引:0,他引:1
Duanfang Sun Jianjun Li Taicheng An Meiying Xu Guoping Sun Jun Guo 《Biotechnology and Bioprocess Engineering》2011,16(5):1009-1018
Packing materials play a key role in waste gas treatment. Organic and inert packing materials have their disadvantages, which
may be minimized by mixed packing. In this study, various operating conditions were applied to evaluate the performance of
structured mixed packing and inert packing materials in toluene biotricklefiltration. Four biotrickle filters were packed
with structured mixed packing materials, namely, ceramic pall rings, ceramic rashig rings, and lava rock. Their toluene removal
capacity was studied for 217 day using a laboratory-scale reaction under various operating conditions. The key elimination
capacity (removal efficiency > 95%) ranking of the biotrickle filters was as follows: Structured mixed packing (306.20 ± 7.90
g/m3/h) > pall ring (156.71 ± 7.84 g/m3/h) > rashig ring (153.31 ± 6.14 g/m3/h) > lava rock (150.32 ± 9.19 g/m3/h). The structured mixed packing and inert packing resulted in excellent toluene-degrading biofilter performance under long-term
operation. The structured mixed packing provided a more rapid startup rate and better process robustness than the inert packing
did. The biotrickle filter with mixed packing materials had a high elimination capacity which makes it suitable for various
real-life applications, whereas the capability of the inert packing material was more suitable for treating a steady low toluene
load. 相似文献
16.
Lihui Wei Corinne Bensimon Julia Lockwood Xuxu Yan Pasan Fernando R. Glenn Wells Yin Duan Yong-Xiang Chen J. Russell Redshaw Peter A. Covitz Terrence D. Ruddy 《Bioorganic & medicinal chemistry》2013,21(11):2903-2911
Coronary artery disease (CAD) is a major cause of death in Canada and the United States. Single photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI) is a useful diagnostic test in the management of patients with CAD. The widely used SPECT MPI agents, 99mTc sestamibi and 99mTc tetrofosmin, exhibit less than ideal pharmacokinetic properties with decreasing uptake with higher flows. 123I has a similar energy as 99mTc, an ideal half life, and is readily available from cyclotrons. The objective of this study was to develop an 123I labeled MPI agent based on rotenone, a mitochondrial complex I inhibitor, as an alternative to currently available SPECT MPI agents. Methods: 123I-CMICE-013 was synthesized by radiolabeling rotenone with 123I in trifluoroacetic acid (TFA) with iodogen as the oxidizing agent at 60 °C for 45 min, followed by RP-HPLC purification. The product was formulated in 5% EtOH in 10 mM NaOAc pH 6.5. The inactive analog 127I-CMICE-013 was isolated and characterized by NMR and mass spectrometry, and the structure determined. Micro-SPECT imaging studies were carried out in normal and infarcted rats. Biodistribution studies were performed in normal rats at 2 h (n = 6) and 24 h (n = 8) post injection (p.i.). Results: 123I-CMICE-013 was isolated with >95% radiochemical purity and high specific activity (14.8–111 GBq/μmol; 400–3000 mCi/μmol). Structural analysis showed that rotenone was iodinated at 7′-position, with removal of the 6′,7′-double bond, and addition of a hydroxy group at 6′-position. MicroSPECT images in normal rats demonstrated homogeneous and sustained myocardial uptake with minimal interference from lung and liver. Absent myocardial perfusion was clearly identified in rats with permanent left coronary artery ligation and ischemia-reperfusion injury. In vivo biodistribution studies in normal rats at 2 h p.i. showed significant myocardial uptake (2.01 ± 0.48%ID/g) and high heart to liver (2.98 ± 0.93), heart to lung (4.11 ± 1.04) and heart to blood (8.37 ± 3.97) ratios. At 24 h p.i., the majority of 123I-CMICE-013 was cleared from tissues, and a significant amount of tracer was found in the thyroid, indicating in vivo deiodination of the tracer. Conclusion: 123I-CMICE-013 is a promising new radiotracer for SPECT MPI with high myocardial uptake, very good target to background ratios and favorable biodistribution characteristics. 相似文献
17.
Non-invasive quantitative measurements are useful for clinical study as these are simple and pain-free procedures. A new non-invasive semi-automatic quantitative measurement method, the improved brain uptake ratio (IBUR) method using 99mTc-ECD SPECT, has recently been reported. If an automatic ROI setting algorithm could be developed to determine the input function for the IBUR method, analysis of regional cerebral blood flow (rCBF) can be completed within a few min without recourse to complex techniques, through a fully automatic rCBF analysis program. The purpose of this study was to develop an automatic input function determination program for 99mTc-ECD non-invasive cerebral blood flow quantification and to confirm the feasibility of use of this program.The images of 15 consecutive patients who underwent both 99mTc-ECD chest RI angiography and SPECT examinations were used for development of the automatic arterial input function program. The images of 69 consecutive patients were used for validation of the program.The coincidence ratio between the ROI automatic method and the manual setting method was 98%. The mean difference in the ROI location was ±6.4 mm in the X direction and ±8.6 mm in the Y direction. Individual rCBF values obtained using these independent techniques were also reasonably well correlated (r = 0.95). The total time for the IBUR analysis using the automatic method is 2–3 min as compared to 20–30 min for the current analysis method. This technique improves the throughput of nuclear medical examinations. 相似文献
18.
《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2001,750(1):147-153
The [13C]octanoic acid breath test was used for the measurement of differences in gastric emptying in preterm infants for the evaluation of pharmacological therapy. In order to perform a good intra-individual comparison of the gastric emptying in preterm infants under non-standardisable test conditions, we adjusted t1/2 for variations in non-recovered label (=label retention) and introduced an “effective half 13CO2 breath excretion time” t1/2eff=t1/2/m expressed as min per percentage of the cumulative dose recovered. In a pilot study, we investigated the action of the gastrointestinal prokinetic drug cisapride on gastric emptying in seven premature infants, of whom four suffered from gastric stasis and three had constipation. The postnatal age and weight at the start of treatment ranged from 15 to 64 days and from 815 to 1635 g, respectively. All infants received the standard formula for premature infants (Nenatal, Nutricia). Cisapride was administered orally 0.2 mg/kg, four times daily. The changes in gastrointestinal motility were studied using the total bowel transit time of carmine red. After 7 days of treatment in all children, the gastric emptying coefficient and the half 13CO2 breath excretion time adjusted for label retention were improved (n=7, the gastric emptying coefficient range before treatment was 1.69–3.34 (mean 2.59±0.80) and after treatment it was 2.79–3.76 (mean 3.28±0.30); the half 13CO2 breath excretion time adjusted for label retention range before treatment was 3.0–14.7 min/% dose (mean 7.0±5.0) and after treatment 2.6–4.0 min/% dose (mean 3.1±0.6). The total bowel transit time was only slightly improved in two patients (n=7, mean total bowel transit time before: 23.7 h compared to mean total bowel transit time after 7 days of treatment: 35.5 h). Side effects during cisapride treatment were not seen. We conclude that in premature infants cisapride is effective in shortening gastric emptying time and reducing gastric stasis; the therapeutic role in constipation has to be further investigated. 相似文献
19.
Yi Zhang Li Xiao Kosta Popovic Xiuzhen Xie Mahendra D. Chordia Leland W.K. Chung Mark B. Williams Wei Yue Dongfeng Pan 《Bioorganic & medicinal chemistry letters》2013,23(23):6350-6354
Synthesis, characterization, in vitro and in vivo biological evaluation of a heptamethine cyanine based dual-mode single-photon emission computed tomography (SPECT)/near infrared fluorescence (NIRF) imaging probe 99mTc-PC-1007 is described. 99mTc-PC-1007 exhibited preferential accumulation in human breast cancer MCF-7 cells. Cancer-specific SPECT/CT and NIRF imaging of 99mTc-PC-1007 was performed in a breast cancer xenograft model. The probe uptake ratio of tumor to control (spinal cord) was calculated to be 4.02 ± 0.56 at 6 h post injection (pi) and 8.50 ± 1.41 at 20 h pi (P < 0.0001). Pharmacokinetic parameters such as blood clearance and organ distribution were assessed. 相似文献
20.
Ashok Behera Indranil Banerjee Kakali De Rudra Narayan Munda Sankha Chattopadhayay Amalesh Samanta Bharat Sarkar Santanu Ganguly Mridula Misra 《Amino acids》2013,44(3):933-946
Peptides are attracting increasing interest in nuclear oncology for targeted tumor diagnosis and therapy. We therefore synthesized new cyclic octapeptides conjugated with HYNIC by Fmoc solid-phase peptide synthesis. These were purified and analyzed by RP-HPLC, MALDI mass, 1H NMR, 13C NMR, HSQC, HMBC, COSY and IR spectroscopy. Conformational analysis of the peptides was performed by circular dichroism spectroscopy, in pure water and trifluoroethanol–water (1:1), revealed the presence of strong secondary structural features like β-sheet and random coils. Labeling was performed with 99mTc using Tricine and EDDA as coligands by SnCl2 method to get products with excellent radiochemical purity >99.5 %. Metabolic stability analysis did not show any evidence of breaking of the labeled compounds and formation of free 99mTc. Internalization studies were done and IC50 values were determined in somatostatin receptor-expressing C6 glioma cell line and rat brain cortex membrane, and the results compared with HYNIC-TOC as standard. The IC50 values of 99mTc-HYNIC-His3-Octreotate (21 ± 0.93 nM) and 99mTc-HYNIC-TOC (2.87 ± 0.41 nM) proved to be comparable. Biodistribution and image study on normal rat under gamma camera showed very high uptake in kidney and urine, indicating kidney as primary organ for metabolism and route of excretion. Biodistribution and image study on rats bearing C6 glioma tumor found high uptake in tumor (1.27 ± 0.15) and pancreas (1.71 ± 0.03). Using these findings, new derivatives can be prepared to develop 99mTc radiopharmaceuticals for imaging somatostatin receptor-positive tumors. 相似文献