Configuration and type-selection of PET/CT and PET/MR equipment during the period of National 14th Five-Year Plan / 中国医学装备

Objective:To explore the configuration conditions and type-selections of positron emission tomography/computed tomography(PET/CT)and positron emission tomography/magnetic resonance(PET/MR)system under the national new policies during the 14th Five-Year Plan period,so as to provide references for configuration and type-selection of PET/CT and PET/MR equipment of medical institutions.Methods:According to the management polices of relevant configurations of PET/CT and PET/MR,which included configuration licensing,use management and configuration plan,and which were issued by China 14th Five-Year Plan,as well as the development trend and characteristics of PET/CT and PET/MR new techniques,the configuration conditions and type-selection plan of PET/CT and PET/MR equipment were analyzed.Results:Under the new polices during national 14th Five-Year Plan,medical institutions should configure PET/CT and PET/MR depended on the condition of institutions,personnel condition,work basis,the supporting facilities and other conditions,and should select the type of PET/CT and PET/MR which can meet the requirements of medical institutions depended on the technique parameters and performance indicators of PET/CT and PET/MR.Conclusions:Since the 14th Five-Year Plan,there were significant changes in the new policies related to the configurations of PET/CT and PET/MR compared to previous policies.The medical institutions should apply configurations and use PET/CT and PET/MR as new requirement,and configure the PET/CT and PET/MR equipment and conduct type-selection of them as various requirements of each institution.

Assessment of hepatic reserve function of cirrhosis liver using dynamic SPECT (99m)Tc-galactosyl human serum albumin scintigraphy / 中华外科杂志

<p><b>OBJECTIVE</b>To evaluate the effectiveness of dynamic SPECT (99m)Tc-galactosyl human serum albumin (GSA) scintigraphy on the assessment of reserve function of cirrhosis liver.</p><p><b>METHODS</b>From January 2010 to December 2011, 55 patients with cirrhosis liver were enrolled in this study. The case numbers of male and female were 43 and 12 respectively and the age was (51 ± 9) years (ranging from 35 to 69 years). After routine biochemistry test, CT scan and (99m)Tc-GSA dynamic SPECT scan were performed in turn using a juxtaposed SPECT/CT system. Then the morphologic volume of liver parenchyma (MLV), functional liver volume (FLV) and the hepatic cell absorption rate constant (GSA-K) were calculated. The correlations between GSA-K and routine biochemistry test, Child-Pugh score, indocyanine green clearance rate (ICG-K) were analyzed. The patients were further divided into 3 groups according to whether there was occlusion or stenosis in the main branch of left portal vein (group 1, n = 5), right portal vein (group 2, n = 13) or not (group 3, n = 37) and the regional hepatic functions index of the 3 groups were compared.</p><p><b>RESULTS</b>The value of FLV of the whole, left and right liver was (594 ± 152) ml, (244 ± 119) ml and (356 ± 171) ml, respectively. There were correlations between GSA-K and total bilirubin, prothrombintime, Child-Pugh score and ICG-K (r = -0.730--0.298, P < 0.05). The FLV and MLV ratios of involved hemiliver to uninvolved hemiliver were 0.09 ± 0.06 and 0.30 ± 0.14 in group 1, 0.57 ± 0.43 and 1.08 ± 0.63 in group 2, 0.71 ± 0.30 and 0.71 ± 0.48 in group 3. The difference in MLV-FLV ratio was signifcant between group 1 and group 3, between group 2 and group 3 (P = 0.000).</p><p><b>CONCLUSIONS</b>The dynamic SPCECT (99m)Tc-GSA scintigraphy can not only assess the whole liver function of cirrhosis liver effectively, but also evaluate the variation of regional liver function accurately.</p>

Application of positron emission tomography molecular probes in hepatocellular carcinoma biological imaging / 中国医学科学杂志(英文版)

Biological behavior is a hot issue in hepatocellular carcinoma (HCC) study. Positron emission tomography (PET), a biological imaging technique, has been widely applied in many types of tumors. It is capable of noninvasive detection of biological behavior. Different radiotracers provide different information of HCC, including glucose/lipid metabolism, DNA synthesis, and apoptosis. In addition, radiotracer uptake relates to biological and clinical prognostic markers. In this article we review the application of several existing and novel radiotracers in PET in HCC study.

CT coronary angiography combined with adenosine stress myocardial perfusion scintigraphy for detecting flow-limiting coronary stenoses / 南方医科大学学报

<p><b>OBJECTIVE</b>To assess the feasibility and accuracy of CT coronary angiography (CTCA) combined with adenosine stress myocardial perfusion scintigraphy (MPS) for diagnosis of flow-limiting coronary stenosis.</p><p><b>METHODS</b>A total of 105 patients with suspected or established coronary artery disease (CAD) underwent CTCA and MPS within 4 weeks before invasive coronary angiography. The accuracy of CTCA/MPS in the diagnosis of flow-limiting coronary stenosis was evaluated in comparison with the results of quantitative coronary angiography and MPS.</p><p><b>RESULTS</b>The sensitivity, specificity, positive predictive value and negative predictive value of CTCA/MPS as a combined approach for detection of flow-limiting coronary stenosis were all 100%. In 16% (9/55) of the patients, revascularization procedures were performed and no flow-limiting stenosis was found.</p><p><b>CONCLUSION</b>Combination of CTCA and MPS has an excellent accuracy for detecting flow-limiting coronary stenosis as compared with quantitative coronary angiography/MPI, and can be a useful gatekeeper for revascularization procedures.</p>

Value of 2-18F-2-deoxy-β-D-glucose PET/CT in tumor detection of patients suspected as having paraneoplastic syndromes / 中华神经医学杂志

Objective To determine the value of 2-18F-2-deoxy-β-D-glucose (18F-FDG)PET/CT in malignancy tumor detection of patients suspected as having paraneoplastic syndrome (PNS).Methods The clinical data of 54 patients suspected as having PNS, underwent PET/CT study in our hospital fiom June 2007 to December 2009, were retrospectively analyzed. The efficacy of 18F-FDG PET/CT on positive detection rate, positive predictive value of malignant tumors and on the detection of malignant tumor markers were analyzed with the results of pathological findings and clinical data;whether the course of disease could affect these detection was also analyzed. Results Positive results of 18F-FDG PET/CT were noted in 17 patients (31.5%), and 13 of them were confirmed as malignant tumors with pathological results. The positive predictive value of 18F-FDG PET/CT was 76.5%. The durations of patients with malignancies were not different from those of patients without malignancies.PET/CT enjoyed a significantly higher efficacy rate in identifying malignant tumors in patients with elevated tumor markers than in patients with tumor markers in normal range (P＜0.05). Conclusion 18F-FDG PET/CT improves the tumor detection rate in PNS suspects, especially in patients enjoying elevated tumor markers.

Automatic synthesis of 18F-FB-RGD and evaluation of its biodistribution / 中华核医学杂志

Objective To evaluate the automatic synthesis of 18F-labeled cyclic RGD peptide c(RGDyK)and its biological distribution in the tumor-bearing mice. Methods N-succinimidyl-4-18 F-fluorobenzoate (18F-SFB) was automatically synthesized and then re-dissolved in acetonitrile (MeCN). The cyclic RGD peptide c(RGDyK) was mixed with an hydrous DMSO and N, N-diisopropyl ethylamine (DIPEA). 18F-FBRGD was obtained by the reaction of peptide solution with 18 F-SFB. The final product was purified by HPLC gradient separation system and solid-phase extraction method. The biodistribution study and competition test of N-4-18F- fluorobenzoyl-RGD (18F-FB-RGD) in the tumor-bearing mice was performed. Results The labeling yield of 18 F-FB-RGD was (33.6 ± 3.5)%. The synthesis time was 110 min. The radiochemical purity was more than 98%. The tumor uptake of 18F-FB-RGD was (3.43 ±0.15), (2.61 ±0.14), (2.11 ±0.13), and (1.79 ±0.18) %ID/g, respectively, at 30, 60, 90 and 120 min after injection. The ratio of tumor to muscle activity ranged from 4.26 ±0.69 to 5.80 ±0.78. The tumor uptake decreased dramatically after RGD blockage. The uptake was (0.46 ±0.21) %ID/g and (2.87 ±0.59) %ID/g in the blocked and unblocked mice, respectively, at 60 min after blockage. Conclusions 18 F-FB-RGD can be automatically synthesized and it may become a promising tumor imaging agent.

18F-FDG PET/CT imaging characteristics of sarcoidosis in 22 cases / 中华核医学杂志

Objective To investigate the imaging characteristics of both intra- and extrathoracic sarcoidosis on 18F-FDG PET/CT.Methods From 2007 Aug.to 2009 Nov.,22 patients( 10 males,12 females) with sarcoidosis,confirmed by pathological study and clinical follow-up,underwent 18 F-FDG PET/CT imaging.The imaging patterns of intrathoracic and extrathoracic lesions were analyzed.The patterns were classified as the typical or atypical ( symmetrical or asymmetrical FDG accumulation and enlargement of hilar lymph nodes) based on PET and CT separately.Nonparametric McNemar test,independent t-test and Fisher exact test were applied for statistical analysis.Results For typical pattern vs atypical pattem identification,PET was significantly different from CT ( 18 and 4 vs 12 and 10,P =0.031 ).In those with atypical pattern demonstrated by CT alone at hilar region,PET showed either symmetrical or asymmetrical accumulation of FDG.Except for mediastinal lymph nodes involvement,lung parenchyma was the second common site ( 19/22,86.4％ ),followed by lymph nodes at abdomen and (or) pelvis ( 12/22,54.5％ ).Conclusion The imaging characteristics of both intra- and extrathoracic sarcoidosis on 18F-FDG PET/CT may be helpful for the diagnosis of atypical sarcoidosis on CT image alone.

Positron emission tomography with special tracers in pulmonary abnormalities / 中华外科杂志

<p><b>OBJECTIVE</b>To assess the value of positron emission tomography (PET) with (11)C-choline (CH), (11)C-methionine (MET), (18)F-fluorothymidine (FLT), and (11)C-acetate (AC) in diagnosis of pulmonary abnormalities and the features of pulmonary abnormalities in PET.</p><p><b>METHODS</b>From June 2002 to June 2007, 100 patients with pulmonary nodules or masses confirmed by CT scans received PET with special tracers. Fifty-eight patients received CH-PET, 16 patients received MET-PET, 22 patients received FLT-PET, 4 patients received AC-PET. PET data was analyzed by visual method and semiquantitative method with standard uptake value (SUV). Diagnoses were compared with pathology and follow-up survey.</p><p><b>RESULTS</b>For identification of pulmonary neoplasms with CH-PET, the sensitivity, specificity and accuracy were 84.2% (32/38), 57.9% (11/19) and 75.4% (43/57). In cancer cases, SUV had no correlation with tumor size or age. For identification of pulmonary neoplasms with MET-PET, the sensitivity, specificity and accuracy were 6/7, 6/9 and 75.0% (12/16). In cancer cases, SUV had not correlation with tumor size or age. For identification of pulmonary neoplasms with FLT-PET, the sensitivity, specificity and accuracy were 85.7% (12/14), 2/8 and 63.6% (14/22). In cancer cases, SUV had not correlation with tumor size or age. In AC-PET, only 1 case of pulmonary metastasis of kidney clear cell carcinoma showed acetate avid. Two squamous cell carcinoma and 1 adenocarcinoma didn't appear abnormal in AC-PET.</p><p><b>CONCLUSION</b>CH, MET, FLT, AC are valuable in diagnosing but also lead to false positive and false negative.</p>

Positron emission tomography imaging of cell transplantation in a rat model of Alzheimer's disease / 中国医学科学院学报

<p><b>OBJECTIVE</b>To explore the value of positron emission tomography (PET) in the Alzheimer's disease (AD) rat model verification and in monitoring the therapeutic effectiveness of cell transplantation.</p><p><b>METHODS</b>A beta(1-40) hippocampus injected rat model was successfully established and neural stem cells were injected into hippocampus. Results of behavior tests and histological examinations were compared between model group and graft group, and then the N-methyl-[(11)C]2-(4 methylaminophenyl)-6-hydroxybenzothiazole ((11)C-PIB) and (18)F-fluorodeoxyglucose ((18)F-FDG) imaging were performed to observe whether the result of imaging was matched with behavior test and histological examination.</p><p><b>RESULTS</b>The Morris water maze showed that the latent period of the escape was significantly longer in model group than in control group (P<0.01). In histological examinations, the neuron loss and A beta deposition were found in hippocampus CA1 and dentate gyrus of rat model. (11)C-PIB imaging showed increased uptake in model rat hippocampus district (P<0.05), while (18)F-FDG imaging showed that the uptake in the injected side of hippocampus in model group was significantly lower than that in the same side in control group (P<0.001). After cell transplantation, the latent period of the escape was significantly shorter in graft group than in model group (P<0.01). Histological examinations showed that there was no obvious changes in A beta deposition; in addition, the neural stem cells differentiated and expressed neuronal nuclei-positive cells, and continuously expressed 5-bromodeoxyuridine-positive cells for six weeks. (11)C-PIB imaging and (18)F-FDG imaging showed the uptakes were not significantly different between between model group and transplantation group(P>0.05).</p><p><b>CONCLUSION</b>(11)C-PIB imaging is useful in diagnosing AD and monitoring the pathological change of AD model in vivo, while (18)F-FDG imaging provides useful visual information for monitoring short-term therapeutic effectiveness of stem cell transplantation.</p>

Research on multifunctional 18F synthesis module with two vessels / 中华核医学杂志

Objective To explore a new 18F multifunctional synthesis module with two vessels to synthesize various kinds of 18F labeled radiopharmaceuticals for clinical utilities. Methods The module with two vessels contained five systems, capture of F ion, the first reaction vessel, the second reaction vessel, high performance liquid chromatography (HPLC) purification, and solid extraction. The two vessels were made of transparent glass and were used to prepare complex products by nucleophilic reaction or hydrolyzation. Results The complex compounds of 18F-ethyl-choline, 18F-N-succinimidyl-4-18 F-fluorobenzoate (SFB), and common compounds of 18F-fluorodeoxyglucose (FDG), 18F-3'-deoxy-3'-18 F-fluorothymidine (FLT) were synthesized by the new module. The uncorrected synthesis yield (EOS) of 18F-SFB, 18F-ethylcholine, and 18F-FDG were (28.2±1.9)% (n=5), (22.5±3.8)%(n=6), and (58.2±5.4)% (n=32), respectively. The corrected synthesis yield of 18F-FLT was (30.1 ±6.2)% ( n = 10). In addition,11C-N-methyl-N-( 1-methylpropyl )-1-( 2-corophenyl )-isoquinoline-3 -carboxamide ( PK11195 ) was also prepared by the module with the yield of (31.2 ± 2.5) % ( n = 3 ). Conclusions The new module with two vessels has been used for synthesis of many 18F compounds and it may have the potential to be used for other more 18F radiopharmaceuticals.

Therapeutic effects of FuZhiSan on Alzheimer's disease rat model:evaluation with PET imaging / 中华核医学杂志

Objective To assess the feasibility of using PET molecular imaging to evaluate the therapeutic effects of traditional Chinese medicine FuZhiSan (FZS) on the model of aging Alzheimer's disease (AD) rats. Methods Twenty aged AD rats (Sparague-Dawley rats,male) were randomly divided into FZS treated group (n = 10) and control group (n = 10). Another 10 healthy adult rats were as blank controls. Morris water maze record system was used for cognitive function assessment. Before and after FZS treatment 18 F-fluorodeoxyglucose (FDG) and 11 C-2- [4'-(methylamino) phenyl] benzothiazol-6-ol ( PIB )PET imaging was undertaken. After post-treatment imaging procedures the brain tissues of all animals were taken for histochemical study,such as staining with HE,congo red,amyloid β (Aβ) immunofluorescence,5-bromo-2-deoxyuridine (BrdU) immunofluorescence and NeuN immunofluorescence. Paired t-test was performed with SPSS 13.0 software for the data analysis. Results The cognitive dysfunction of aging AD rats was improved after FZS treatment. The escape latency in FZS treated group was significantly shorter than that of control group ((32.5 ±10.8) s vs (102.6±8.8) s,t =15.7987,P=0. 0001). Diffuse neuronal loss and Aβ deposition were detected in the hippocampus and cortex in the aged AD rats. The imaging data showed that brain glucose metabolism was amended in FZS treated group while the abatement of amyloid deposition was not significant. Immunofluorescence results indicated that the neuronal proliferation was more remarkable in FZS treated group. Conclusions It may be feasible to use PET imaging as a method to evaluate the therapeutic effect in AD rats. FZS may ameliorate memory dysfunction of aged AD rats. Its mechanism may be partly contributed to the enhancement of the neuronal proliferation and survival.

18F-FLT uptake in human colorectal cancer cells in relation to early response to radiation therapy:an in vitro study / 中华核医学杂志

Objective To evaluate whether 18F-fluorothymidine(FLT) can be used to monitor early response to irradiation in colorectal cancer (CRC).Methods SW480 cells were cultured and irradiated with 0, 10, and 20 Gy.Twenty-four hours later, morphological changes, apoptosis, necrosis, proliferation,and cell cycle phases were observed.Uptake of 18F-FLT was measured in these tumors in vitro from 24 h to 72 h after irradiation.The one-way analysis of variance was used to analyze the data.Results Apoptotic and necrotic cells were detected 24 h after radiotherapy.SW480 cells proliferation was significantly delayed after irradiation in 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenylte-trazolium bromide (MTI) assay.Cell cycle analysis showed that SW480 cells had a decreased fraction of cells in S phase( from 33.23% to 9.24%,then to 5.43% ) and an arrested fraction in G0-G1.After SW480 cells were cultured for60 min, the uptake of 18F-FLT was (5.21 ± 1.60) %; and 24 h after irradiation of 10 Gy, the uptake decreased significantly to (4.27±0.48)% (F=8.253, P=0.009).And 72 h after irradiation, the uptake further decreased significantly to (3.39 ± 0.59) % ( F = 36.715, P＜0.001 ).In tumor tissue, the uptake of 18F-FLT reduced significantly 72 h after radiotherapy (10 Gy:F = 12.388, P = 0.007; 20 Gy:F = 16.744, P = 0.004) and the attenuation degree increased with the radiation dose.Conclusion The uptake of 18F-FLT in SW480 cells or in CRC could reflect the changes of SW480 cells in proliferation, cell cycle re-distribution, cell apoptosis and necrosis.The results suggest that 18F-FLT may be used for monitoring early response to irradiation of CRC.

Prediction of metastatic tendency of human colorectal cancer using PET imaging in nude mice / 中华核医学杂志

Objective To evaluate the predictive value of 18F-fluorodeoxyglucose (FDG) and 18F-fluorothymidine(FLT) PET in monitoring the metastatic potential of human colorectal cancer (CRC).Methods Human CRC cell lines SW480 and SW620 were cultured and implanted into nude mice to create CRC models. Tumor growth,metastatic status and survival were assessed in CRC bearing mice. Uptake of 18F-FDG and 18F-FLT in SW480 and SW620 cells was detected In vitro at 0,30,60,90,120 min after incubation. PET images of both tracers were acquired for SW480 and SW620 tumor-bearing mice using the small animal PET at 60 min after tracer injection. Region of interest (ROI) was drawn using Image J software on reconstructed PET images. Immunocytochemistry and Western blot analysis of the tumor tissue were performed. The correlation between tracer uptake and tumor marker expression was evaluated using linear regression. Results Compared with SW620 tumor-bearing mice,SW480 induced tumor grew much faster ( t = - 3.332,P = 0.004),the tumor-bearing mice had more serious dyscrasia ( t = 2.240,P = 0.038 ),shorter survival and higher metastatic rate. In vitro study,the uptake of both 18F-FDG and 18F-FLT in SW620 cells was lower than that in SW480 cells. 18F-FLT uptake was higher than 18F-FDG uptake in both SW480 and SW620 cells. After incubation for 60 min,the uptake of 18F-FDG in SW480 and SW620 cells was ( 1.76 ± 0.87 )% and ( 1.14 ± 0.38 )%,respectively ( t = - 2.507,P = 0.021 ); while the uptake of 18F-FLT in SW480 and SW620 cells was (5.21 ± 1.60)% and (2.90 ± 1.82)%,respectively (t =3.497,P =0.002). In micro-PET study,the 18F-FDG radioactivity ratio of tumor to non-tumor (T/NT) in SW480 and SW620 tumors was 2.69 ± 0.98 and 3.09 ± 1.26 respectively (t =0.657,P =0.524); while T/NT of 18F-FLT in SW480 and SW620 tumors was 3.65 ±0.51 and 2.22 ±0.42 (t =6.491,P ＜0.001 ),respectively. In immunocytochemistry and western blot assay,heat shock protein(HSP) 27,Integrin β3,vascular endothelial growth factor receptor 2 ( VEGFR2 ) and Ki67 were all over expressed in two kinds of tumor cells with different intensities. HSP27 and Integrin β3 expression was higher in SW480 cells than that in SW620 cells. While VEGFR and Ki67 expression was lower in SW480 cells than that in SW620 cells. The uptake of 18F-FLT closely correlated with the expression of HSP27 ( r =0.924,P =0.004) and Integrin β3 (r=0.813,P =0.025). 18F-FDG uptake inversely correlated with the survival of tumor-bearing mice (r =0.500,P=0.017). Conclusions The uptake of 18F-FDGand 18F-FLT may reflect different biological characteritics of CRC. High 18F-FLT uptake in CRC on PET scan may predict high metastatic tendency.

Pitfalls in positron emission tomography/computed tomography imaging: causes and their classifications / 中国医学科学杂志(英文版)

<p><b>OBJECTIVE</b>To describe the pitfalls in positron emission tomography/computed tomography (PET/CT) imaging and classify them according to the principles of their generation.</p><p><b>METHODS</b>We summarized retrospectively the 18F-fluorodeoxyglucose (FDP) PET/CT imaging pitfalls through reviewing the PET/CT images of 872 patients. The pitfalls were divided into artifacts and infrequent physiological uptake, and the artifacts were further classified according to their causes. Meanwhile, we calculated the incidences of various pitfalls. Whether the PET/CT pitfalls influenced the diagnostic decision was analyzed. The appearances of pitfalls in PET were also described.</p><p><b>RESULTS</b>Pitfalls could be found in PET/CT images of 684 (78.4%) patients. Artifacts were found in 664 (76.15%) patients, and could be classified into self-factor artifacts and equipment- or technology-related artifacts. Among self-factor artifacts, respiratory motion (57.5%), postprandial or hyperglycemia artifacts (2.41%), and metal or high density matter artifacts (1.38%) were frequent. As for equipment- or technology-related factors, injection point outleakage or radiotracer contamination (13.88%) and truncation artifacts (1.83%) were most common ones. Infrequent physiological FDG uptakes, including fatty uptake, endometrial uptake, and bilateral breast feeding period uptake, were found in 20 (2.29%) patients. Among all pitfalls, the artifacts in 92 (13.4%) patients and infrequent physiological uptakes in 6 (0.88%) patients affected the diagnostic results. Artifact images in PET could be described as hot or cold area and the images of infrequent physiological uptake were always shown as hot area.</p><p><b>CONCLUSIONS</b>The incidence of pitfall in PET/CT imaging was high and the causes of pitfalls are various. Among all causes that artifacts generated, respiratory motion is the most common. Some pitfalls may disturb clinical physicians' decision, so it is important to recognize artifacts and physiological uptake, and distinguish them from pathological uptakes.</p>

Primary application of identification-aided system for diagnosis and differential diagnosis of emerging infectious diseases / 中华实验和临床病毒学杂志

<p><b>OBJECTIVE</b>To verify the rate of diagnostic fitting between the clinic and the indentification-aided for diagnosis and differential diagnosis system, for emerging infections diseases (EID) established.</p><p><b>METHODS</b>314 cases of 49 kinds of contagious diseases diagnosed and another 186 patients with fever who not diagnosed were tested by the system.</p><p><b>RESULTS</b>Preliminary verification was made in 314 cases diagnosed which classified to 49 kinds of contagious diseases of infectious diseases and the results showed that the coincidence rate of clinical diagnosis and first diagnosis of this system was 61.9%; the suggestive rate of first three diagnoses was 78.1%, and that of first five diagnoses was 86.6%. The diagnosis of another 186 patients with fever were diagnosed by the system and the results showed that the coincidence rate of clinical diagnosis and first diagnosis was 59.7%; the suggestive rate of first three diagnoses was 77.9%, and that of first five diagnoses was 85.4%.</p><p><b>CONCLUSIONS</b>The system can accurately suggest impossible diagnosis and differential diagnosis, and be useful for our medical work.</p>

Transferrin receptor imaging for tracing mesenchymal stem cells implanted in the spinal cord / 南方医科大学学报

<p><b>OBJECTIVE</b>To explore the feasibility of tracing mesenchymal stem cells in vivo with scintigraphy.</p><p><b>METHODS</b>Transferrin receptor expression of cultured mesenchymal stem cells (hMSCs) was quantified with radioligand-receptor binding assay before the cells were transplanted into the spinal cord of rabbits. (131)I-labeled transferrin was then administered into the subarachnoid space of the rabbits, and scintigraphic images were acquired with a gamma camera at different time points after the administration. In the control experiments, (131)I-labeled human serum albumin was used in stead of (131)I-transferrin as the tracer, or only PBS was injected without stem cell transplantation. The images were semi-quantitatively analyzed with region of interest (ROI) techniques, and the phosphor imaging on the spinal sections were performed.</p><p><b>RESULTS</b>Radioligand-receptor binding assay showed 10 770 binding sites with high affinity (KD=0.982 nmol/L) for Fe saturated transferrin on each human mesenchymal cell. Visible accumulation of radioactivity at the cell transplantation sites was observed 16 h and 24 h after intrathecal injection of (131)I-transferrin tracer, but not in two control groups. ROI analysis showed that the difference between (131)I-transferrin and the control groups was statistically significant (P<0.05). Phosphor imaging further verified that it was the specific coupling of transferrin to the implanted cells that resulted in radioactivity accumulation at the transplantation sites.</p><p><b>CONCLUSIONS</b>Transferrin receptor imaging is capable of in vivo tracing of the implanted stem cells, and has the potential for use in non-invasive monitoring for stem cell transplantation therapy after further technical improvements.</p>

D2 receptor expression on immortalized human neural progenitor cell line hNPC-TERT in vitro and in vivo / 南方医科大学学报

<p><b>OBJECTIVE</b>To observe D(2) receptor expression on human neural progenitor cell line hNPC-TERT before and after transplantation into rabbit central nervous system.</p><p><b>METHODS</b>D(2) receptor expression on cultured hNPC-TERT cells was verified and quantitatively analyzed with immunofluorescence assay and receptor radio ligand binding assay, respectively. 3 x 10(6) hNPC-TERT cells were implanted in the spinal cord of New Zealand rabbit with HeLa cells as the control. Two days after implantation, positron-emission tomography (PET) scan with (11)C-raclopride as the radiotracer was performed in the living animals or for the isolated spinal cords, and cryosections of the spinal cord containing the implanted cells were prepared for immunofluorescence assay.</p><p><b>RESULTS</b>Cultured hNPC-TERT cells showed high expression of D(2) receptor (Bmax=8 x 10(4)). PET scans of the rabbits identified visible radioactive accumulations at the site where hNPC-TERT cells were implanted but not at the site of HeLa cell implantation. Region of interest analysis showed a significant difference between the two cells in the maximal standard uptake value at the cell implantation sites. The results were further confirmed with ex vivo PET imaging of the spinal cord and tissue immunofluorescence assay.</p><p><b>CONCLUSION</b>Human neural progenitor cells hNPC-TERT highly express dopamine D(2) receptors and retain this capacity after implantation into the spinal cord, suggesting their potential for treatment of such nerve system disease as Parkinson syndrome.</p>

Fluorine-18 fluorodeoxyglucose-positron emission tomography imaging of carcinoma of cardia or fundus of stomach / 中华外科杂志

<p><b>OBJECTIVE</b>To investigate the value of fluorine-18 fluorodeoxyglucose (FDG)-positron emission tomography (PET) in carcinoma of cardia or fundus of stomach.</p><p><b>METHODS</b>From April 1999 to April 2005, 57 patients with carcinoma of cardia or fundus of stomach were imaged with FDG-PET. FDG-PET imaging were analyzed by visual method combined with semiquantitative analysis. The results were compared with pathological findings and follow-up results.</p><p><b>RESULTS</b>In 29 untreated patients, 25 T(2) to T(4) tumors were all FDG avid and 4 T(1) cases showed nothing abnormal at the primary site. In 24 patients performed curative operation 40 resected enlarged lymph nodes beyond 1 cm were diagnosed correctly by FDG-PET. FDG-PET revealed distant metastases in 5 patients and corrected them from curative surgery candidates to late stage. In 28 treated patients FDG-PET confirmed 22 cases with recurrence or metastasis.</p><p><b>CONCLUSIONS</b>FDG-PET has limited value in confirming T stage in carcinoma of cardia or fundus of stomach. It showed potential in N and M staging and predicting treatment response.</p>

Value of carbon-11 choline positron emission tomography in patients with pulmonary abnormalities / 中华外科杂志

<p><b>OBJECTIVE</b>To assess the value of carbon-11 choline (CH) positron emission tomography (PET) in patients with pulmonary nodules.</p><p><b>METHODS</b>From September 2002 to December 2004, 39 patients with pulmonary nodules were imaged with CH-PET. CH-PET data was analyzed by visual method and semiquantitative method. When pulmonary nodules with abnormal CH uptake appeared in PET scans confirmed by visual method, their maximum and mean standard uptake value (SUVmax and SUVmean) were measured using semiquantitative method. Diagnoses were confirmed by surgery or biopsy and follow-up survey.</p><p><b>RESULTS</b>Twenty-four cancerous and 3 inflammatory nodules and 1 bronchogenic cyst were detected by CH-PET and were diagnosed malignant with visual method. Three bronchial alveolar carcinoma, 2 metastatic tumor from kidney and colon, 3 fibrous nodules, 1 cryptococcosis, 1 hamartoma and 1 sclerosing hemangioma showed nothing abnormal in PET scans. For identification of pulmonary nodules with CH-PET, the sensitivity was 89% (24/29), the specificity was 60% (6/10), and the accuracy was 77% (30/39). There were differences in SUV between 8 squamous cell carcinomas and 9 adenocarcinomas (Z = -2.937, -2.887, P < 0.01). In diagnosing 70 resected enlarged lymph nodes beyond 1 cm in 17 lung cancer patients, CH-PET had the sensitivity of 86% (25/29), the specificity of 90% (37/41), and the accuracy of 89% (62/70). CH-PET confirmed 7 distant metastases in 25 lung cancer patients. In 5 cases suspected brain metastases CH-PET identified 2 cases positive correctly.</p><p><b>CONCLUSIONS</b>CH-PET can confirm malignant pulmonary nodules, but still there were false positive and false negative cases. CH-PET can evaluate N stage effectively in patients with lung cancer. CH-PET can depict brain metastases accurately.</p>

Fluorine-18 fluorodeoxyglucose uptake in patients with benign pulmonary nodules / 中华外科杂志

<p><b>OBJECTIVE</b>To assess the features of fluorine-18 fluorodeoxyglucose (FDG) uptake in patients with benign pulmonary nodules.</p><p><b>METHODS</b>From October 1998 to July 2004, 47 patients with benign pulmonary nodules were imaged with FDG-positron emission tomography (PET). Diagnoses were confirmed by surgery. FDG-PET data was analyzed by visual method and semi-quantitive method. When pulmonary nodules with abnormal FDG intake appeared in PET scans confirmed by visual method, their maximum and mean standard uptake value (SUVmax and SUVmean) and SUV of normal lung (SUVlung) were measured using semiquantitative method.</p><p><b>RESULTS</b>Twenty-one cases showed nothing abnormal in PET scans, including 17 calcification and fibrosis, 2 hamartomas and 2 sclerosing hemangiomas. 26 pulmonary nodules were detected by FDG-PET (17 active tuberculous, 6 inflammatory pseudotumors, 3 cryptococcosis). FDG uptake of these 26 nodules was higher than that of normal lung (SUVmax, SUVmean and SUVlung were 3.04 +/- 1.65, 2.48 +/- 1.35 and 0.40 +/- 0.07, respectively, P < 0.001). Correlations were not found between FDG uptake and nodule size or SUV of normal lung or age or blood glucose level in these 26 patients (P > 0.05). SUV in 9 cases (9/26, 35%) were beyond 2.5.</p><p><b>CONCLUSIONS</b>Some benign pulmonary nodules were FDG avid.</p>