Biomedical subjects

Dong Soo Lee

Publications and source records attributed to Dong Soo Lee.

At least 19 recordsLinked to original sources

PubMed2007

Progressive improvement of myocardial perfusion after off-pump revascularization with bilateral internal thoracic arteries: comparison of early versus 1-year postoperative myocardial single photon emission computed tomography.

OBJECTIVE: We evaluated the time course of myocardial perfusion improvement after off-pump revascularization. METHODS: Seventy-six patients who underwent off-pump coronary bypass with bilateral internal thoracic arteries for revascularization of the left coronary territory were studied. Myocardial single photon emission computed tomography was performed preoperatively and at 3 months and 1 year postoperatively. Myocardial perfusion was quantified with automatic software, and the left coronary territory was divided into 16 segments. As an indicator of the ischemic myocardium, the reversibility score was defined as a measure of rest minus stress perfusion values. A total of 403 segments that showed a reversibility score of 7 or greater preoperatively were included. RESULTS: The reversibility score was improved significantly at 3 months postoperatively (P < .001) and further improved 1 year after the operation (P < .001). When the patients were divided into 2 groups based on the type of bilateral internal thoracic arteries used (group Y: Y-composite graft, n = 39; group I: bilateral in situ grafts, n = 37), the reversibility score was improved significantly 3 months after the operation (P < .001) and further improved 1 year after the operation (P < .001) in both groups. There were no significant differences in the reversibility scores between groups Y and I at postoperative month 3 (P = .463). The scores approached zero in both groups at 1 year postoperatively (group Y, -1.7% +/- 7.9%; group I, 1.3% +/- 7.2%). CONCLUSIONS: The myocardial reversibility score improved greatly during the first 3 months after the operation and further improved until 1 year postoperatively. Perfusion improvement was similar between the Y-composite and bilateral in situ internal thoracic artery grafts in terms of the reversibility score.

Coronary Artery Bypass, Off-Pump↗

PubMed2006

Assessment of regional GABA(A) receptor binding using 18F-fluoroflumazenil positron emission tomography in spastic type cerebral palsy.

Periventricular leukomalacia (PVL) due to hypoxic-ischemic insult to the immature brain, chorioamnionitis and maternal infection are the major etiological factors of spastic type cerebral palsy (CP). Despite advances in preventing and treating certain causes of CP, the number of patients has remained essentially unchanged and the pathophysiological mechanisms related to motor dysfunction remain poorly understood. In this study, statistical parametric mapping (SPM) analysis of cerebral gamma-aminobutyric acid (GABA) receptor PET imaging using [18F]-fluoroflumazenil showed increased GABA(A) receptor binding in the bilateral motor and visual cortices in spastic diplegia (SD) type CP patients (n = 20) compared with normal controls (n = 10). As GABA(A) receptor signaling modulates biological perception and production of movement, complex motor skills and use-dependent plasticity in the motor cortex, increased GABA(A) receptor binding in the motor cortex might play a important role in poor motor control. Decreased GABA(A) receptor binding was seen in the brain stem in SD CP patients, which appears to be related to spastic symptom.

Adolescent↗

PubMed2006

Development of acetylated HDD kit for preparation of 188Re-HDD/lipiodol.

A lipiodol solution of (188)Re-4-hexadecyl-2,2,9,9-tetramethyl-4,7-diaza-1,10-decanedithiol ((188)Re-HDD/lipiodol) is in clinical study for liver cancer therapy. However, formulation of it is difficult due to highly active and unstable sulfhydryl groups. We produced new kits using diacetylated HDD (AHDD), in which sulfhydryl groups are protected. We found that AHDD kit can replace HDD kit due to an increased stability for formulation, the better radiolabeling efficiency (78%) and the equivalent biodistribution pattern in mice.

Acetylation↗

PubMed2006

Differential effect of intracoronary infusion of mobilized peripheral blood stem cells by granulocyte colony-stimulating factor on left ventricular function and remodeling in patients with acute myocardial infarction versus old myocardial infarction: the MAGIC Cell-3-DES randomized, controlled trial.

BACKGROUND: The efficacy of intracoronary infusion of granulocyte colony-stimulating factor (G-CSF) mobilized peripheral blood stem cells (PBSCs) has not been compared between patients with acute (AMI) versus old myocardial infarction (OMI). In addition, the potential risk of restenosis associated with G-CSF-based stem cell therapy has not been evaluated in the setting of drug eluting stent (DES) implantation. METHODS AND RESULTS: We randomly allocated 96 patients with myocardial infarction who underwent coronary revascularization with DES for the culprit lesion into 4 groups. Eighty-two patients completed 6-month follow-up; AMI cell infusion (n=25), AMI control (n=25), OMI cell infusion (n=16), and OMI control group (n=16). In cell infusion groups, PBSCs were mobilized by G-CSF for 3 days and delivered to infarcted myocardium via intracoronary infusion. The AMI cell infusion group showed a significant additive improvement in left ventricular ejection fraction (LVEF) and remodeling compared with controls (change of LVEF: +5.1+/-9.1% versus -0.2+/-8.6%, P<0.05; change of end-systolic volume: -5.4+/-17.0 mL versus 6.5+/-21.9 mL, P<0.05). In OMI patients, however, there was no significant change of LVEF and ventricular remodeling in spite of significant improvement of coronary flow reserve after cell infusion. G-CSF-based cell therapy did not aggravate neointimal growth with DES implantation. CONCLUSIONS: Intracoronary infusion of mobilized PBSCs with G-CSF improves LVEF and remodeling in patients with AMI but is less definite in patients with OMI. G-CSF-based stem cell therapy with DES implantation is both feasible and safe, eliminating any potential for restenosis.

Acute Disease↗

PubMed2006

Development of quantification software using model-based segmentation of left ventricular myocardium in gated myocardial SPECT.

Gated myocardial single photon emission computed tomography (SPECT) is being used for the diagnosis of coronary artery diseases. In this study, we developed new software for the quantification of volumes and ejection fraction (EF) on the gated myocardial SPECT data using a cylindrical model. Volumes and EF by developed software were validated by comparing with those quantified by quantitative gated SPECT (QGS) software. Cylinder model for left ventricular myocardium was used to eliminate background activity and count profiles across the myocardium were fitted to the Gaussian curve to determine the endocardial and epicardial boundary. End-diastolic volume (EDV), end-systolic volume (ESV) and EF were calculated using this boundary information. Gated myocardial SPECT was performed in 83 patients. EDV, ESV and EF values estimated using present method were compared to those obtained using the commercialized software QGS, and reproducibility in the parameter estimation was assessed. EF, EDV and ESV obtained using two methods were correlated well (correlation coefficients = 0.96, 0.96 and 0.98). The correlation between the parameters repetitively estimated from the same data set by an operator was very high (correlation coefficients = 0.96, 0.99 and 0.99 for EF, EDV and ESV). On the repeated acquisition, reproducibility was also high with correlation coefficients of 0.89, 0.97 and 0.98. The present software will be useful for the development of new parameters for describing the perfusion and function of the LV.

Aged↗

PubMed2006

An improved method of 18F peptide labeling: hydrazone formation with HYNIC-conjugated c(RGDyK).

Radiolabeled alpha(v)beta(3)-integrin antagonists are increasingly investigated as a means of imaging angiogenesis. Several methods of labeling alpha(v)beta(3)-integrin binding peptide with (18)F have been reported recently. In the present study, we devised a straightforward means for labeling Arg-Gly-Asp (RGD) peptide with (18)F via hydrazone formation between c(RGDyK)-hydrazinonicotinic acid (HYNIC) (3) and 4-[(18)F]-fluorobenzaldehyde ([(18)F]4). The resulting reaction mixture was purified by HPLC to give 4'-[(18)F]-fluorobenzylidenehydrazone-6-nicotinamide-c(RGDyK) ([(18)F]5). The conjugation efficiency of 3 and 4 to form [(18)F]5 was 95.2%, and the radiochemical purity of [(18)F]5 after purification was >99%. The specific activity of [(18)F]5 estimated by radio-HPLC was 20.5 GBq/mumol (end of synthesis). Competitive binding assay of c(RGDyK) (1) and 5 was performed using [(125)I]iodo-c(RGDyK) as a radioligand, and K(i) values were found to be 2.8 and 21.7 nM, respectively. For the biodistribution study, the angiogenic mouse model was established by inducing unilateral ischemia on the left hindlimbs of ICR mice after femoral artery ablation. Seven days after inducing ischemia, [(18)F]5 was administered to the mice through the tail vein. Ischemic muscle uptake of [(18)F]5 was significantly higher than that of normal muscle (P<.01). Specific uptake was confirmed by coinjection of 1 with [(18)F]5. Here, we successfully labeled RGD peptide with (18)F via hydrazone formation between 3 and 4, resulting to [(18)F]5. [(18)F]5 was found to have high affinity for alpha(v)beta(3)-integrin and to accumulate specifically in ischemic hindlimb muscle of mice. We suggest that (18)F labeling via formation of hydrazone between HYNIC peptide and [(18)F]4 is a useful method for labeling c(RGDyK), which can be applied for imaging angiogenesis.

Animals↗

PubMed2006

Cortical activity at rest predicts cochlear implantation outcome.

The functional status of central neural pathways, in particular their susceptibility to plasticity and functional reorganization, may influence speech performance of deaf cochlear implant users. In this paper, we sought to determine how brain metabolic activity measured before implantation relates to cochlear implantation outcome, that is, speech perception. In 22 prelingually deaf children between 1 and 11 years, we correlated preoperative glucose metabolism as measured by F-18 fluorodeoxyglucose positron emission tomography with individual speech perception performance assessed 3 years after implantation, while factoring out the confounding effect of age at implantation. Whereas age at implantation was positively correlated with increased activity in the right superior temporal gyrus, speech scores were selectively associated with enhanced metabolic activity in the left prefrontal cortex and decreased metabolic activity in right Heschl's gyrus and in the posterior superior temporal sulcus. These results reinforce the notion that implantation should be performed as early as possible to prevent cross-modal takeover of auditory regions and suggest that rehabilitation strategies may be more efficient if they capitalize on general cognitive functions instead of only targeting specialized circuits dedicated to auditory and audiovisual pattern recognition.

Auditory Cortex↗

PubMed2006

The neural correlates of cross-modal interaction in speech perception during a semantic decision task on sentences: a PET study.

Speech perception in face-to-face conversation involves processing of speech sounds (auditory) and speech-associated mouth/lip movements (visual) from a speaker. Using PET where no scanner noise was present, brain regions involved in speech cue processing were investigated with the normal hearing subjects with no previous lip-reading training (N = 17) carrying out a semantic plausibility decision on spoken sentences delivered in a movie file. Multimodality was ensured at the sensory level in all four conditions. Sensory-specific speech cue of one sensory modality, i.e., auditory speech (A condition) or mouth movement (V condition), was delivered with a control stimulus of the other modality whereas speech cues of both sensory modalities (AV condition) were delivered during bimodal condition. In comparison to the control condition, extensive activations in the superior temporal regions were observed bilaterally during the A condition but these activations were reduced in extent and left lateralized during the AV condition. Polymodal region such as left posterior superior temporal sulcus (pSTS) involved in cross-modal interaction/integration of audiovisual speech was found to be activated during the A and more so during the AV conditions but not during the V condition. Activations were observed in Broca's (BA 44), medial frontal (BA 8), and anterior ventrolateral prefrontal (BA 47) regions in the left during the V condition, where lip-reading performance was less successful. Results indicated that the speech-associated lip movements (visual speech cue) rendered suppression on the activity in the right auditory temporal regions. Overadditivity (AV > A + V) observed in the right postcentral region during the bimodal condition relative to the sum of unimodal speech conditions was also associated with reduced activity during the V condition. These findings suggested that visual speech cue could exert an inhibitory modulatory effect on the brain activities in the right hemisphere during the cross-modal interaction of audiovisual speech perception.

Adult↗

PubMed2006

In vivo monitoring of DNA vaccine gene expression using firefly luciferase as a naked DNA.

The administration of naked DNA into animals is increasing as a research tool to develop DNA vaccine. To monitor the distribution and duration of gene expression of a DNA vaccine in living organisms, we used the naked DNA encoding firefly luciferase (Fluc) as an imaging reporter gene, and evaluated in vivo bioluminescent images in a murine model. We observed bioluminescence at the injection site and at inguinal lymph node from 10h to 24h post-injection when DNA vaccine encoding Fluc (pcDNA3.1-Fluc) was injected into the bilateral posterior flanks in mice. Fluc gene expressions at injection sites and unilateral posterior flank inguinal lymph node were also confirmed by RT-PCR. However, when pcDNA3.1-Fluc was injected into the mid-dorsum bioluminescent signals were observed at the injection site for up to 14 days post-injection, but no bioluminescent signals were detected in inguinal lymph nodes. Concurrent mRNA expressions of Fluc gene at injection sites but not at inguinal lymph nodes were confirmed by RT-PCR. These findings suggest that optical imaging using Fluc could be useful for monitoring the location, intensity and duration of gene expression of naked DNA vaccines in living animals non-invasively and repetitively.

Animals↗

PubMed2006

The clinical impact of 18F-FDG PET in papillary thyroid carcinoma with a negative 131I whole body scan: a single-center study of 108 patients.

OBJECTIVE: To assess whether FDG PET could localize the recurrent or metastatic lesions in papillary thyroid cancer patients with negative radioiodine scan. METHODS: Whole body PET was performed after injecting 370-555 MBq of 18F-FDG in 108 patients, who were suspected of having recurrence or metastasis and whose 131I whole body scans were negative. Recurrence or metastasis occurred in 63 patients by pathology or clinical assessment, whereas 45 patients remained in remission. RESULTS: FDG PET revealed recurrence or metastases in 59 patients (sensitivity 93.7%), whereas thyroglobulin (Tg) levels were elevated in 41 (sensitivity 65.1%). In 35 of 45 patients in remission, FDG PET was negative (specificity 77.8%). When patients positive for antithyroglobulin antibody were excluded, the sensitivity and specificity of serum Tg became 84.8% and 46.9%, respectively. Compared to Tg measurement, FDG PET detected more metastatic lesions in cervical lymph nodes. Of 40 patients with a negative radioiodine scan showing diffuse hepatic uptake, metastases occurred in 23 patients and remission in 17. FDG PET showed 100% sensitivity and 76.5% specificity in the detection of recurrence in these 40 patients. CONCLUSION: FDG PET is useful for localizing recurrent or metastatic lesions in 131I scan-negative thyroid cancer patients. In particular, it is superior to serum Tg measurement for identifying metastases to cervical lymph nodes. We recommend its use in cases of negative radioiodine scan with diffuse hepatic uptake.

Adult↗

PubMed2006

Efficacy of therapeutic angiogenesis by intramyocardial injection of pCK-VEGF165 in pigs.

BACKGROUND: Intramyocardial injection of vascular endothelial growth factor (VEGF) plasmid DNA was studied to demonstrate improvement of regional myocardial function. METHODS: Twenty-one pigs that had undergone ligation of the left anterior descending coronary artery were randomly allocated to one of two treatments: intramyocardial injection of pCK-VEGF165 (VEGF group) or pCK-Null (control group) into the ischemic border zone. Electrocardiogram-gated single-photon emission computed tomography was performed 30 and 60 days after the coronary ligation. Segmental variables of perfusion and function were automatically quantified using a 20-segment model. In the segmental analysis, 119 segments were selected for analysis (71 segments in the VEGF group; 48 segments in the control group). Histologic analysis was also performed in the myocardial tissue of the ischemic border zone. RESULTS: At day 30, there were no significant differences in segmental perfusion, wall thickening, and wall motion between the two groups. In the VEGF group, all variables of perfusion, wall thickening, and wall motion were significantly improved at day 60 compared with those at day 30 (p < 0.05), while there were no differences in the control group. At day 60, perfusion (p = 0.018), wall motion (p = 0.004), and wall thickening (p = 0.068) of the VEGF group were improved compared with those of the control group. Histologic analysis showed that microcapillary density was significantly higher in the VEGF group than the control group (p < 0.001). CONCLUSIONS: Intramyocardial injection of pCK-VEGF165 significantly augmented neoangiogenesis in the ischemic area and improved regional myocardial function as well as myocardial perfusion.

Animals↗

PubMed2006

A case of Bickerstaff's brainstem encephalitis; the evidence of cerebellum involvement by SPM analysis using PET.

Although the clinical manifestations such as drowsiness, brisk reflexes, extensor plantar responses and hemisensory disturbance usually are considered to suggest Bickerstaff's brainstem encephalitis (BBE) rather than Miller Fisher syndrome (MFS), the nosological relationship between BBE and MFS has yet to be established. Herein, we report upon a 58-year-old man who showed ophthalmoplegia, ataxia and consciousness disturbance. In the absence of any abnormality on brain MRI, electrophysiological studies and SPM analysis using (18)F-FDG PET showed evidence of brainstem and cerebellum involvements.

Ataxia↗

PubMed2006

Synthesis and evaluation of benzothiophene derivatives as ligands for imaging beta-amyloid plaques in Alzheimer's disease.

The imaging of the distribution of beta-amyloid (Abeta) plaques in the brain is becoming an important diagnostic modality in Alzheimer's disease (AD). Here, we synthesized novel benzothiophene derivatives and labeled them with (18)F for the potential diagnostic imaging of AD patients using positron emission tomography. The K(i) values of benzothiophene derivatives were evaluated by competitive binding assay using 2-(3'-[(125)I]iodo-4'-N-methylaminophenyl)benzothiazole as a radioligand and Abeta(1-40) or Abeta(1-42) aggregates as receptors. All synthesized benzothiophene derivatives showed high binding affinities (K(i)=0.28-6.50 nM) to both Abeta(1-40) and Abeta(1-42) aggregates. Binding affinities were increased by O-alkylation or N-alkylation of 2-(4'-hydroxyphenyl)benzothiophene or 2-(4'-aminophenyl)benzothiophene. Biodistribution studies of 2-(4'-O-(2''-[(18)F]fluoroethyl)hydroxyphenyl)benzothiophene ([(18)F]) and 2-(4'-O-(3''-[(18)F]fluoropropyl)hydroxyphenyl)benzothiophene ([(18)F]) in normal mice were performed after intravenous injection through the tail vein. In biodistribution data, [(18)F] and [(18)F] showed high initial brain uptakes at 2 min (5.2+/-0.4% and 3.3+/-0.2% ID/g, respectively), and brain activities washed out to 2.0+/-0.2% and 0.5+/-0.1% ID/g at 4 h, respectively. In conclusion, benzothiophene derivatives showed excellent binding affinities for Abeta aggregates and high initial brain uptakes in normal mice.

Alzheimer Disease↗

PubMed2006

Evaluation of transcriptional activity of the oestrogen receptor with sodium iodide symporter as an imaging reporter gene.

BACKGROUND: Oestrogen receptors are ligand-dependent transcription factors whose activity is modulated either by oestrogens or by an alternative signalling pathway. Oestrogen receptors interact via a specific DNA-binding domain, the oestrogen responsive element (ERE), in the promoter region of sensitive genes. This binding leads to an initiation of gene expression and hormonal effects. OBJECTIVE: To determine the transcriptional activity of the oestrogen receptor, we developed a molecular imaging system using sodium iodide symporter (NIS) as a reporter gene. METHODS: The NIS reporter gene was placed under the control of an artificial ERE derived from pERE-TA-SEAP and named as pERE-NIS. pERE-NIS was transferred to MCF-7, human breast cancer cells, which highly expressed oestrogen receptor-alpha with lipofectamine. Stably expressing cells were generated by selection with G418 for 14 days. After treatment of 17beta-oestradiol and tamoxifen with serial doses, the (125)I uptake was measured for the determination of NIS expression. The inhibition of NIS activity was performed with 50 micromol x l(-1) potassium perchlorate. RESULTS: The MCF7/pERE-NIS treated with 17beta-oestradiol accumulated (125)I up to 70-80% higher than did non-treated cells. NIS expression was increased according to increasing doses of 17beta-oestradiol. MCF7/pERE-NIS treated with tamoxifen also accumulated (125)I up to 50% higher than did non-treated cells. Potassium perchlorate completely inhibited (125)I uptake. When MDA-MB231 cells, the oestrogen receptor-negative breast cancer cells, were transfected with pERE-NIS, (125)I uptake of MDA-MB-231/pERE-NIS did not increase. CONCLUSION: This pERE-NIS reporter system is sufficiently sensitive for monitoring transcriptional activity of the oestrogen receptor. Therefore, cis-enhancer reporter systems with ERE will be applicable to the development of a novel selective oestrogen receptor modulator with low toxicity and high efficacy.

Breast Neoplasms↗

PubMed2006

Detection of Brucella canis and Leptospira interrogans in canine semen by multiplex nested PCR.

Brucella canis and Leptospira interrogans are pathogenic bacteria that cause brucellosis and leptospirosis in dogs around the world. Both diseases can be diagnosed serologically, but the direct detection of these organisms in canine semen is needed when it is used for artificial reproduction. We have been attempting the artificial reproduction of guide dogs for greater breeding efficiency and for this purpose have developed a multiplex nested PCR technique for the detection of B. canis and L. interrogans in the semen and cryoprotective agent (CPA). Our results demonstrated the high sensitivity and simplicity of this technique in the detection of these organisms in canine semen and that will be useful in routine diagnosis. Since they have been found to stay alive in canine semen and CPA up to 48 hr, canine semen for breeding purposes should be checked for contamination by the PCR assay.

Animals↗

PubMed2006

[A randomized, prospective, comparative, multicenter study of rabeprazole and ranitidine in the treatment of reflux esophagitis].

BACKGROUND/AIMS: This study was done to evaluate the efficacy of rabeprazole (proton-pump-inhibitor) and ranitidine (H(2)-receptor antagonist) in the symptom relief and treatment of erosive esophagitis diagnosed by endoscopy. METHODS: A total of 110 patients with typical gastroesophageal reflux disease (GERD) symptoms were enrolled in this multicenter study. They were randomized into rabeprazole group (53 patients) and ranitidine group (57 patients) respectively. The patients in rabeprazole group were given 10 mg of rabeprazole and ranitidine group received 300 mg of ranitidine before breakfast and dinner for 8 weeks. After the end of treatment, we evaluated the endoscopic healing rate of reflux esophagitis and symptomatic improvement. RESULTS: After 8 weeks of treatment, rabeprazole group showed significantly higher complete endoscopic cure rate than ranitidine group (86.8% [46/53] vs. 57.9% [33/57], p=0.001) and higher symptomatic improvement of heartburn (91.2% [31/34] vs. 76.2% [32/42], p=0.085), especially in the first 7 days (76.7% vs. 45.3%, p=0.008). Also, rabeprazole group showed significantly higher improvement of regurgitation symptom than ranitidine group (100% [35/35] vs. 83% [39/47], p=0.009). Both group showed no differences in the improvement of chest pain and globus sensation. All the adverse events (rabeprazole group 4 events vs. ranitidine group 3 events) were mild and there was no abnormality in laboratory test. CONCLUSIONS: In patients with GERD, rabeprazole 10 mg b.i.d. is superior to ranitidine 300 mg b.i.d. in healing of reflux esophagitis and resolving typical GERD symptoms. Rabeprazole is an effective and well-tolerated drug for GERD treatment.

2-Pyridinylmethylsulfinylbenzimidazoles↗

PubMed2006

[Toxic hepatitis associated with carp juice ingestion].

The potential hepatotoxicity of herbal remedies and/or health foods is usually ignored in daily life. There have been cases showing the toxic hepatitis and renal failure associated with the ingestion of raw carp bile. We experienced a case of toxic hepatitis without any evidence of renal failure that was associated with carp juice ingestion. The clinical manifestations were characterized by nausea and vomiting after the ingestion of carp juice for 3 months. The diagnosis of toxic hepatitis was made on the basis of the patient's history, laboratory data, RUCAM (Russel Uclaf Causality Assessment) and the results of ultrasonography guided liver biopsy. The patient showed rapid improvement after instituting supportive therapy.

Adult↗

PubMed2006

Tissue distribution of 18F-FDG-labeled peripheral hematopoietic stem cells after intracoronary administration in patients with myocardial infarction.

UNLABELLED: Adult stem cell therapy is expected to improve left ventricular function in patients with myocardial infarction. Because of the low risk of arrhythmia and the maximal concentration at the target tissue, intracoronary infusion of stem cells is preferred. The aim of this study was to investigate the homing and tissue distribution of intracoronary injected peripheral hematopoietic stem cells labeled with 18F-FDG. METHODS: Seventeen patients with myocardial infarction were included as the intracoronary injection group (14 males, 3 females; age, 58 +/- 12 y). Three patients underwent intravenous stem cell injection as the intravenous injection group (3 males, 0 females; age, 50 +/- 20 y). After mobilization with granulocyte colony-stimulating factor (G-CSF), peripheral stem cells were collected by means of apheresis. 18F-FDG labeling of stem cells was performed for 40 min with gentle intermittent mixing at 37 degrees C. The mean labeling efficiency was 72% (range, 46%-95%), and 44.4-175 MBq (1.2-5 mCi) of 18F-FDG-labeled stem cells were injected via an intracoronary catheter after stenting in infarct-related arteries. PET/CT images were obtained with a 3-dimensional acquisition mode 2 h after intracoronary infusion. RESULTS: Two hours after intracoronary infusion, 1.5% (range, 0.2%-3.3%) of injected stem cells accumulated at the infarcted myocardium. Outside of the myocardium, spleen, liver, bladder, and bone marrow showed a high stem cell accumulation. The delayed image of a patient up to 20 h showed a prolonged residence of stem cells at the myocardium. Intravenous injection of stem cells showed a high initial lung uptake with no myocardial activity. CONCLUSION: We have shown that 18F-FDG-labeled stem cell PET could be used to assess the tissue distribution and to measure the amount of stem cells at a target tissue. 18F-FDG-labeled stem cell PET can be used to measure and optimize the amount of stem cells injected.

Adult↗