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The clinical value of whole body positron emission tomography/computed tomography (PET/CT) as an imaging tool in diagnosis of ophthalmic tumors was investigated.The retrospective observational case series were performed on the patients with suspected ophthalmic tumors who underwent whole body PET/CT.The golden standard of diagnosis was the final pathological diagnosis or the results of long-term follow-up for patients without surgery/ biopsy.PET/CT findings were compared with the golden standard.The sensitivity,specificity,accuracy and positive likelihood ratio of PET/CT in the detection of ophthalmic tumors were calculated.The clinical application of PET/CT in different types of ophthalmic tumors was evaluated.The results showed that 30 patients (18 males and 12 females) with a mean age of 43.0 years (range 4-63 years) were collected.The mean sizes of orbital tumors and intraocular tumors were 26.8 mm×17.8 mm and 11.2 mm×6.1 mm,respectively.The overall sensitivity,specificity,accuracy and positive likelihood ratio of whole body PET/CT in ophthalmic tumors were 76.5％,71.4％,75.0％ and 2.67,and were 62.5％,100％ and 70.0％ in intraocular tumors,and those were 100％,60.0％ and 84.6％ in orbital tumors,respectively.PET/CT findings were applied to help make appropriate treatment options in 27 out of 30 patients (90.0％),and 12 (40.0％) patients changed the treatment strategy.False negative results in 4 cases and false positive results in 2 cases were observed in this series.It was suggested that PET/CT was an effective imaging modality in detecting,diagnosing and developing therapeutic schedule for patients with ophthalmic tumors.It was more sensitive and accurate for detecting orbital tumors than for detecting intraocular tumors.
ABSTRACT
The clinical value of whole body positron emission tomography/computed tomography (PET/CT) as an imaging tool in diagnosis of ophthalmic tumors was investigated.The retrospective observational case series were performed on the patients with suspected ophthalmic tumors who underwent whole body PET/CT.The golden standard of diagnosis was the final pathological diagnosis or the results of long-term follow-up for patients without surgery/ biopsy.PET/CT findings were compared with the golden standard.The sensitivity,specificity,accuracy and positive likelihood ratio of PET/CT in the detection of ophthalmic tumors were calculated.The clinical application of PET/CT in different types of ophthalmic tumors was evaluated.The results showed that 30 patients (18 males and 12 females) with a mean age of 43.0 years (range 4-63 years) were collected.The mean sizes of orbital tumors and intraocular tumors were 26.8 mm×17.8 mm and 11.2 mm×6.1 mm,respectively.The overall sensitivity,specificity,accuracy and positive likelihood ratio of whole body PET/CT in ophthalmic tumors were 76.5％,71.4％,75.0％ and 2.67,and were 62.5％,100％ and 70.0％ in intraocular tumors,and those were 100％,60.0％ and 84.6％ in orbital tumors,respectively.PET/CT findings were applied to help make appropriate treatment options in 27 out of 30 patients (90.0％),and 12 (40.0％) patients changed the treatment strategy.False negative results in 4 cases and false positive results in 2 cases were observed in this series.It was suggested that PET/CT was an effective imaging modality in detecting,diagnosing and developing therapeutic schedule for patients with ophthalmic tumors.It was more sensitive and accurate for detecting orbital tumors than for detecting intraocular tumors.
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Objective To evaluate the feasibility of monitoring the gene expression of VEGF165 via the diglycylcysteine (GGC) reporter gene system by reporter probe of 99Tcm-GH. Methods DNA fragments encoding GGC binding motifs were prepared by PCR and positioned at the C end of VEGF165 gene after the linearization of pcDNA3-VEGF165 plasmid. A replication-defective adenovirus vector Ad5-VEGF165GGC motif-internal ribosomal entry site(IRES) -enhanced green fluorescent protein (EGFP) (Ad5-VIE)was constructed, with a cytomegalovirus (CMV) early promoter driving the expression of VEGF165 gene,GGC motif and EGFP, under the aid of an IRFS. A replication-defective adenovirus carrying the Ad5-EGFP was used as the control. Mensenchymal stem cells (MSC) were infected with the recombinant adenovirus at a multiplicity of infection (MOI) from 0 to 100 infectious units (0,10,25,50,100). The cellular uptake of 99Tcm-GH in infected MSC were then studied at 30, 60, 90 and 120 min. VEGF165 was detected by quantitative reverse transcriptase real-time PCR (RT-PCR), Western-blot, and immunohistochemisty. EGFP was observed by RT-PCR and fluorescence microscopy. The correlation analysis was studied between the cellular uptake of 99Tcm-GH and the expression of VEGF165. SPSS 13.0 was applied for statistical analysis. Independent samples t-test, q-test and Pearson correlation coefficient were used. Results After infected with different viral titer of Ad-VIE, the cellular uptake of 99Tcm-GH increased with the increasing virus titer(r2 =0.86, P ＜0.05), with the peak rate (7.94 ±0.75) % at MOI = 100. In time-dependent uptake study, the cellular uptake rates increased rapidly with the time extension, and the highest uptake occurred at 120 min with the peak uptake rate (7.72 ±0.22)%. The uptake rates of 99Tcm-GH in Ad5-VIE-infected cells were significantly higher than those of Ad5 -EGFP-transfected cells at all time points (t = 15.10- 54.92, all P ＜0.05). The VEGF165 and EGFP mRNA levels increased with increasing virus titer, and the VEGF165 mRNA correlated well with the EGFP mRNA(r2 = 0. 99, P ＜ 0.05). After infected with different MOI of Ad5-VIE, good relationship was found between the cellular uptake of 99Tcm-GH and the expression of VEGF165protein in MSC(r2 =0.90, P ＜0.05). Inmunohistochemisty showed VEGF165 protein expressed obviously at Ad5-VIE-infected MSC, and the EGFP was observed by fluorescence microscopy. Conclusions The cellular uptake of 99Tcm-GH in Ad5-VIE-infected MSC are well correlated with the expression of VEGF165 in vitro. The expression of therapeutic gene VEGF165 can be monitored by the GGC peptide expression.
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Objective To investigate the feasibility of rat sodium/iodide symporter (rNIS) as a reporter gene monitoring rat bone marrow mesenchymal cells (rBMSC) transplanted to rat myocardium in vivo.Methods Recombinated adenovirus vector was constructed by rNIS/enhanced green fluorescence protein (EGFP) (Ad-rNIS/EGFP).rBMSC transfected by Ad-rNIS/EGFP were studied using fluorescence microscope.Fifteen rats were transplanted with rBMSC and randomly divided into three groups:rNIS group (with rNIS transfection), blocked group (with rNIS transfection) by oral intake of perchloric sodium before planar imaging(GE Millennium MPR SPECT), and control group (without rNIS transfection).All rats underwent 99Tcm-pertechnetate planar imaging.The biological distribution of 99Tcm-pertechnetate was studied.The expressions of rNIS gene and protein in myocardium were measured by real time polymerase chain reaction (PCR) and western blot, respectively.The expressions of CD29, CD44, CD90, CD11b, CD34 and CD45 were measured by immunohistochemistry.Results rBMSC transfected by Ad-rNIS/EGFP showed EGFP expression under fluorescence microscope.The transplanted rat myocardium could be visualized on 99Tcm-pertechnetate planar imaging in rNIS group.The relative uptake ratio( Rheart/Rhmb, RUR) was 6.7 ±0.4.RUR in control group (3.0 ±0.2) was lower than that in rNIS group (t =2.78, P=0.03).The percentage injection dose per gram of tissue (% ID/g) of the transplanted myocardium was 60.2 ± 20.8 in rNIS group,which was higher than that (2.5 ± 0.4) % ID/g of control group ( t = 7.13, P＜0.001 ).rNIS gene and protein were highly expressed in transplanted myocardium in rNIS group but less expressed in control group.The expressions of CD29, CD44 and CD90 were positive, CD45 and CD45 negative CD11b mildly positive in the myocardium transplanted with infective rBMSC.Conclusion rNIS can efficiently monitor rBMSC transplanted to rat myocardium.
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<p><b>OBJECTIVE</b>Radionuclide imaging of reporter gene expression holds promise for noninvasive monitoring of gene therapy. Herpes simplex virus 1-thymidine kinase (HSV1-tk) has been successfully applied to the tumor tissue.We explored the feasibility of the expression imaging of HSV1-tk reporter gene in rat myocardium by using SPECT reporter probe (131)I-2'-fluoro-2'-deoxy-1-beta-D-arabinofuranosyl-5-iodouracil ((131)I-FIAU) and autoradiography (ARG).</p><p><b>METHODS</b>The recombinant Ad5-tk carrying HSV1-tk gene and adenovirus (Ad5-null) as vector were constructed and intramyocardially injected into SD rats. Experiment was grouped for different aims as follows: (1) Influence of time on the imaging after transfection reporter gene: rats were injected with (131)I-FIAU at day 1, 2, 3, 5 and 7 after transfection of 1 x 10(8)pfu Ad5-tk; (2) Influence of various titers on the imaging: rats underwent intramyocardial injection with various titers of Ad5-tk (5 x 10(8), 1 x 10(8), 5 x 10(7), 1 x 10(7)pfu). After 2 days, rats were injected with (131)I-FIAU in tail vein. Equal volume Ad-nulls was intramyocardially injected to control rats. Rats were killed 24 h after injection of (131)I-FIAU and the hearts were rapidly dissected for gamma counts measurement. The total myocardial (131)I-FIAU accumulation was quantified in percent of injected dose per gram myocardium (%ID/g). The myocardial reporter gene expression was semi-quantitatively determined by ARG and RT-PCR.</p><p><b>RESULTS</b>ARG and RT-PCR showed that the local expression of reporter gene increased in proportion with increasing titer and decreased in proportion with time post injection. The semi-quantitative assay showed there were significant correlations among %ID/g, RT-PCR and ARG: r(2) = 0.963, P < 0.05 for RT-PCR and ARG; r(2) = 0.996, P < 0.01 for %ID/g and ARG in rats received various reporter gene titers at identical time point post injection; r(2) = 0.950, P < 0.05 for RT-PCR and ARG; r(2) = 0.980, P < 0.01 for %ID/g and ARG for rats received identical reporter gene titer on various time points post injection.</p><p><b>CONCLUSIONS</b>The present study showed that cardiac reporter gene imaging with HSV1-tk as reporter gene and (131)I-FIAU as reporter probe was feasible in rats. The optimal Ad5-tk titer is 1 x 10(8) pfu and the optimal imaging time is 24 h to 48 h post gene transfer. HSV1-tk/FIAU may be used for the noninvasive monitoring of cardiac gene therapy.</p>
Subject(s)
Animals , Female , Rats , Autoradiography , Gene Expression , Genes, Reporter , Herpesvirus 1, Human , Genetics , Myocytes, Cardiac , Cell Biology , Diagnostic Imaging , Metabolism , Rats, Sprague-Dawley , Thymidine Kinase , Genetics , Tomography, Emission-Computed, Single-Photon , TransfectionABSTRACT
<p><b>OBJECTIVE</b>To explore the feasibility of single photon emission computed tomography (SPECT) detection of heart reporter gene expression and observed the optimal transfecting titer and imaging time by using herpes simplex virus 1-thymidine kinase (HSV1-tk) as reporter gene and 131I-2'-fluoro-2'-deoxy-1-beta-D-arabinofuranosyl-5-iodouracil (131I-FIAU) as reporter probe in rabbit myocardium.</p><p><b>METHODS</b>The recombinant Ad-tk carrying HSV1-tk gene and adenovirus (Ad) as vector was constructed and intramyocardially injected to rabbits at various concentrations (1 x 10(9) pfu, 5 x 10(8) pfu, 1 x 10(8) pfu, 5 x 10(7) pfu, 1 x 10(7) pfu). Two days later, rabbits were injected with 600 microCi 131I-FIAU in ear-margin vein and then underwent SPECT myocardium imaging for detection of HSV1-tk expression at 6 h, 24 h, 48 h and 72 h after injection, rabbits with 1 x 10(9) pfu Ad-tk injection were imaged at 96 h and 120 h. Rabbits were sacrificed after imaging and the total myocardial 131I-FIAU accumulation was quantified in percent of injected dose per gram myocardium (% ID/g). The myocardial Ad-tk expression was determined with RT-PCR.</p><p><b>RESULTS</b>Reporter gene was detected by SPECT imaging in the injection site while not detected in the control myocardium and site remote from injection. RT-PCR results also evidenced HSV1-tk express in the injection site. The SPECT target/nontarget ratio was correlated with ex vivo gamma-counting (r2 = 0.933, P<0.01) and expression of HSV1-tk (r2 = 0.877, P<0.01). Myocardial accumulation could be identified at viral titers as low as 1 x 10(7) pfu by SPECT imaging.</p><p><b>CONCLUSION</b>The cardiac SPECT reporter gene imaging with HSV1-tk as reporter gene and 131I-FIAU as reporter probe is feasible.</p>
Subject(s)
Animals , Female , Male , Rabbits , Gene Expression , Gene Transfer Techniques , Genes, Reporter , Heart , Diagnostic Imaging , Myocardium , Metabolism , Thymidine Kinase , Genetics , Tomography, Emission-Computed, Single-Photon , Transfection , UracilABSTRACT
<p><b>OBJECTIVE</b>To evaluate if 99mTc-HYNIC-annexin V may be used to detect the early chemotherapeutic effect and to determine the best timing for detecting apoptosis in vivo.</p><p><b>METHODS</b>Annexin V was labeled with 99mTc using HYNIC as a bifunctional agent. Normal Kunming mice received inoculation of Ehrlich ascites cells into the right upper limb. After the tumor reached 1 cm in diameter, the mice were randomly divided into saline treatment group as control and cyclophosphamide (150 mg/kg injected intraperitoneally) treatment group. 99mTc-HYNIC-annexin V was injected intravenously at 1 h and 24 h after treatment. Region of interest technique (ROI) from the SPECT images taken at different time was used to get the ratio of tumor/limb in each group. TUNEL staining was used to detect apoptotic cells and the rates of positive stained cells were calculated.</p><p><b>RESULTS</b>After treatment with saline, only little amount of the radiolabeled tracer could be seen in the tumor and showed weak image of the tumor. But after 24 h of treatment with cyclophosphamide, clear image on the tumor could be seen. 24 h after the treatment of cyclophosphamide, the ratio of tumor/limb was (6.27 +/- 0.24) which was much higher than that at 24 h after treatment with saline (2.36 +/- 0.18) and that at 1 h after cyclophosphamide treatment (4.00 +/- 0.38). At 24 h after cyclophosphamide treatment, TUNEL staining showed a significantly higher rate of apoptotic cells in the mice.</p><p><b>CONCLUSION</b>99mTc-HYNIC-annexin V can be used as an apoptosis-imaging agent to detect and evaluate the early curative effect after chemotherapy. The effective detection of apoptotic response in tumor with 99mTc-HYNIC-annexin V requires a 24 h interval after chemotherapy. SPECT images can be obtained at 60 min after injection of the imaging agent. It suggests that 99mTc-HYNIC-annexin V may become a promising agent for apoptosis-imaging in clinical application.</p>
Subject(s)
Animals , Male , Mice , Annexin A5 , Pharmacokinetics , Antineoplastic Agents, Alkylating , Therapeutic Uses , Apoptosis , Carcinoma, Ehrlich Tumor , Diagnostic Imaging , Drug Therapy , Pathology , Cyclophosphamide , Therapeutic Uses , Neoplasm Transplantation , Organotechnetium Compounds , Pharmacokinetics , Radiopharmaceuticals , Pharmacokinetics , Random Allocation , Tissue Distribution , Tomography, Emission-Computed, Single-PhotonABSTRACT
<p><b>BACKGROUND</b>The YIGSR is a pentapeptide, from the laminin-1 of the beta1 chain, which can mediate cell adhesion and bind the 67 kD laminin receptor. The purpose is to evaluate the usefulness of (99m)Tc-YIGSR, a novel tumour radiotracer, in the receptor imaging of Ehrlich ascites tumour.</p><p><b>METHODS</b>Using S-acetly-NH3-MAG3 as chelate, YIGSR, a pentapeptide from laminin, was tagged with (99m)Tc. (99m)Tc-YIGSR was detected in the tumour group bearing Ehrlich ascites tumour and blocked group. Tumour, normal, inflammatory and blocked groups were imaged.</p><p><b>RESULTS</b>Through reverse phase Sep-Pak C18 chromatogram, it was revealed that YIGSR could conjugate with S-acetly-NH3-MAG3, and be radiolabelled at room temperature and neutral pH with a radiolabelling yield of 62%, and of 4% without chelate. (99m)Tc-YIGSR was rapidly cleared from kidney, then liver. The imaging findings showed tumour tissue accumulated initial radioactivity at fifteen minutes after injection in the tumour group, and the uptake increased to peak at three hours with a tumour/muscle ratio (T/M) of 11.36, then cleared slowly to a T/M of 7.50 at eight hours. The tumour uptake of radiotracer in blocked group was significantly lower with T/M of 4.61 at three hours and 0.89 at eight hours. The T/M was only 3.72 at three hours and 1.29 at eight hours after injection in inflammatory group. Compared with inflammatory group and control obstructive group, the ratio of T/M in tumour group was significantly different (P < 0.001).</p><p><b>CONCLUSIONS</b>Using S-acetly-NH3-MAG3, we radiolabelled YIGSR with (99m)Tc. (99m)Tc-YIGSR possesses many merits of tumour imaging: rapid visualization, high sensitivity and specificity, and satisfactory target/nontarget ratio. Our data suggest (99m)Tc-YIGSR is a promising tumour radiotracer.</p>
Subject(s)
Animals , Female , Mice , Carcinoma, Ehrlich Tumor , Diagnostic Imaging , Laminin , Oligopeptides , Pharmacokinetics , Radionuclide Imaging , Radiopharmaceuticals , Pharmacokinetics , Technetium , Technetium Tc 99m Mertiatide , Tissue DistributionABSTRACT
<p><b>AIM</b>To study the varies and effects of ischemic preconditioning of myocardium on every part of adrenergic receptor-adenyl cyclase system in rats in vivo.</p><p><b>METHODS</b>SD rats were randomly divided into three groups: CON group (n = 6), IP group (n = 12) and I/R group (n = 12). Surgical procedure included intermittent left coronary artery occlusion and reperfusion. After the procedure, the hearts were extracted. We analyzed the infarct size by TTC staining, measured serum myocardial enzymes, studied the beta-AR Bmax and KD by radioligand binding assay of receptors (RAB), and checked the activity of AC and the content of cAMP by radioimmunoassay (RIA).</p><p><b>RESULTS</b>Infarct area were much smaller in IP group than in I/R group (P < 0.05). CK, CK-MB, LDH were significantly higher in I/R group (P < 0.01). The Bmax of beta-AR in IP group were much higher than in I/R group (P < 0.01). No difference of KD could be seen between IP and I/R group. In IP group, the activity of AC and the content of cAMP were higher than I/R group (P < 0.05).</p><p><b>CONCLUSION</b>Ischemic preconditioning can protect the heart from necrosis and reduce endo-enzyme leakage. Ischemic preconditioning can increase the density of beta-AR, the activity of AC and the content of cAMP, which shows that the system of adrenergic receptor-adenyl cyclase system probably takes part in the protection of IP.</p>