1.Monitoring novel ovarian carcinoma associated genes using cDNA expression microarray
Xiaohong CHANG ; Yexia CHENG ; Xinyan ZHANG ; Heng CUI ; Jie FENG ;
Chinese Journal of Obstetrics and Gynecology 2001;0(06):-
Objective To explore the gene expression pattern of sample of human ovarian carcimoma Method The difference in gene expression between normal and neoplastic human ovarian tissues were investigated,we described the assembly and utilization of a 512 member cDNA microarray Result Thirty seven genes expressed in ovarian cancer were screened out,14 genes were up regulated,23 genes were down regulated Conclusion cDNA microarray for analysis of gene expression pattern is an effective method to identify novel ovarian cancer associated genes
2.HIGH LEVEL EXPRESSION AND ACTIVITY DETECTION OF SINGLE CHAIN IMMUNOTOXIN 183B_2ScFvPE38 AGAINST OVARIAN CARCINOMA
Fanglei YOU ; Jie FENG ; Yexia CHENG ; Tianyun FU ; Yu YAO ;
Acta Anatomica Sinica 1953;0(01):-
Objective To prepare the immunotoxin protein (183B 2ScFvPE38) which might be useful in immuno guided therapy for ovarian carcinoma and study the activity of the protein. Methods The methods of ELISA and cytotoxicity were used to study the immunotoxin after induced with IPTG and the activity of the immunotoxin. Results The expressed fusion proteins were detected mostly as inclusion bodies at high level, and soluble immunotoxins were also observed. The results showed liable activity of antibody part and toxic part. Conclusion The recombinant fusion protein 183B 2ScFvPE38 keeps the activity of both components and might be of great use in the future to deal with ovarian carcinoma. [
3.Impact of misregistration between SPECT and CT on attenuation correction of myocardial perfusion imaging
Kemin HUANG ; Yanlin FENG ; Guanghua WEN ; Weitang LIANG ; Lin LI ; Yexia FENG
Chinese Journal of Nuclear Medicine and Molecular Imaging 2014;34(2):107-111
Objective To evaluate the effects of misregistration with different directions and magnitudes between SPECT and CT on image quality and semi-quantification of MPI.Methods The data of 19 healthy volunteers (11 males,8 females ; mean age:(65.3 ± 9.6) years) were retrospectively analyzed.They all had a low pretest likelihood of coronary artery disease according to exercise and rest 99Tcm-MIBI MPI.The CT attenuation correction (CTAC) was performed on a SPECT/CT system.The CT images were manually shifted by 0.5,1.0,1.5,2.0,2.5,3.0,3.5,4.0,4.5 cm distance along the up/down,left/ right,and anterior/posterior axes respectively by using the system built-in software.The counts of the left ventricle were measured using myocardial Bull's eye generated from the reconstructed CTAC images.The image quality and semi-quantification of the CTAC images reconstructed from the raw data with and without shifting were compared and analyzed.Paired t test was used to analyze the data.Results There was no visible artifact with 0.5 cm shifting.The image quality was deteriorated significantly and the counting difference was significant with shifting distance greater than or equal to 1.0 cm.The image artifact of apex wall was mainly due to the upward shift,anterior and apex wall due to the downward shift,septal wall due to the leftward shift,anterior,apex and lateral wall due to the rightward shift,lateral and infero-posterior wall due to the forward shift,anterior,apex and septal wall due to backward shift.The counting difference caused by the downward shift was significantly more severe than that caused by the upward shift ((-9.68±8.06) % and (-2.04±1.83)%,t=6.573,P<0.01) ; and the rightward shift was more severe than the leftward shift ((-9.02± 8.47) % and (-4.38±3.67) % ; t =1.987,P<0.05).The image artifacts in anterior,apex and lateral walls were more severe than those in the infero-posterior and septal walls.Conclusions CTAC image artifacts in myocardial perfusion SPECT/CT studies could be caused by misregistration ≥ 1.0 cm.Different directions and magnitudes of shift could result in different degrees of attenuation artifacts at different locations on the original images.
4.Identification of T cell epitopes from ovarian cancer associated anti-idiotype antibody
Wei LI ; Heng CUI ; Xiaohong CHANG ; Hongyan CHENG ; Yexia CHENG ; Jie FENG ; Tianyun FU
Chinese Journal of Obstetrics and Gynecology 2008;43(10):764-769
Objective To identify the T cell epitopes from ovarian cancer associated anti-idiotypic antibody 6B11in order to explore the molecular basis of 6B11 induced cellular immune responses against ovarian cancer.Methods Potential human leukocyte antigen(HLA)A0201 ligands were predicted by using SYFPEITHI algorithm and tested by the T2 binding assay for screening of HLA-A2 binding peptides from 6B11 complimentary determining region(CDR).Cytotoxic T lymphocytes(CTL)to 6B11 or peptides were generated by 3 rounds of in vitro stimulation with 6B11 or peptide-pulsod dendritic cells(DC),and then tested by 51Cr-release assay to ascertain the CTL epitope of 6B11.Cell proliferation assay was performed by using 6B11 specific CTL as responder cells and peptide-pulsed DC as stimulators to ascertain the helper T lymphocyte(Th)epitope of 6B11.Cytokine assay and interferon-γ ELISPOT assay were performed to verify the CTL and Th epitope of 6B11 further.Results Light chain CDR3 peptide(VL CDR3)of 6B11 induced specific CTL to kill HLA-A2 and target antigen positive ovarian cancer cells,which could be blocked by anti human major histocompatibility complex(MHC)Ⅰ antibody.Heavy chain CDR3 peptide(VH CDR3)of 6B11 stimulated the proliferation of 6B11-primed CTL,which could be blocked mainly by anti human MHC-Ⅱ antibody,and further experiments showed that part of the VH CDR3 peptide-primed CTL killed K562 cells.Peptides in VL CDR3 and VH CDR3 were the CTL and Th epitope mimicking the original antigen of 6B11 respectively.Collaboration of 6B11 CTL and Th epitope,or 6B11 CTL epitope and keyhole limpet hemocyanin(KLH),the former was more powerful in inducing specific cellular immune responses against ovarian cancer.6B11 or corresponding CTL and Th epitope specific CIL secreted high levels of interleukin-2 (1630,1503 ng/L)and interferon-γ(5620,5421 ng/L),while basal level of interleukin-4 was detected (253,274 ng/L).ELISPOT assay confirmed the existence of specific interferon-γ secreting cells in 6811 or epitopes specific CTL(196/1×106 T cell,184/1×106 T cell).Conclusions VL CDR3 and VH CDR3 peptides of 6B11 are the CTL and Th epitopes mimicking original antigen which could duplicate the activity of intact 6B11 to induce the cellular immune responses against ovarian cancer.The results have significant theoretical and practical value in application of anti-idiotypic antibody ag anti tumor vaccine.The acquired CTL and Th epitopes as constituents of future multiple peptides against ovarian cancer could be used in peptide vaccine based ovarian cancer therapy.
5.Effect of reduced expression of Her2 by RNA interference on the biological characters of ovarian carcinoma cells
Kefang WANG ; Heng CUI ; Jie FENG ; Rong YANG ; Xudong LIANG ; Xiaohong CHANG ; Yi LI ; Yexia CHENG ; Hongyan CHENG ; Xue YE
Chinese Journal of Obstetrics and Gynecology 2008;43(8):622-625
Objective To observe the effects of short hairpin RNA (shRNA) targeting Her2 on its gene expression when the shRNA was stably transfected into human ovarian cell lines, SKOV3 and SKOV3. ipl, which have different extent of malignancy and investigate the changes of the biological characters of the two cell lines after the stable transfection. Methods The plasmids expressing shRNA targeting Her2 gene were transfected into SKOV3 and SKOV3. ipl cells. The stably transfected cells were gained by antibiotic screening. The expression of Her2 before and after the transfection was detected by RT- PCR and western blot. The transwell experiment was used to observe the invasion ability of the cancer cells before and after the transfection, and the parent and the transfected cells were injected into nude mice to observe the tumor growth. Results After the stable transfection with Her2 shRNA, mRNA and protein levels of Her2 gene in SKOV3 and SKOV3. ipl cells were remarkably reduced. The expression of mRNA were (68.0±3. 1) %, (40. 8±2. 0) %, (99. 9±1.3) %, (42. 4±2. 5) %. The expression of protein were (72. 1±3.4) %, (36. 4±1.5) %, (98.2±1.7) %, (40. 7±2. 1) %. The invasion ability into basilar membrane of the transfected cells was greatly reduced compared with the parent cells. The invasion cell numbers were 7.6±1.1, 1.8±0. 8, 36. 2±9.7, 15.7±7. 2. The growth rate of the planted tumors was lower in transfected groups than that of the parent groups. Conclusions (1) The expression of Her2 gene in SKOV3 and SKOV3. ipl cells was remarkably reduced by RNA interference targeting Her2. (2) The biological characters of SKOV3 and SKOV3. ipl cells are changed when the expression of Her2 gene is reduced by RNA interference.
6.Impact of different reconstruction algorithms and ordered subset expectation maximization reconstruction parameters on quantitative results in SPECT/CT
Kemin HUANG ; Yanlin FENG ; Weitang LIANG ; Lin LI ; Yexia FENG ; Dalang DENG ; Weiping HE
Chinese Journal of Medical Imaging Technology 2018;34(1):103-108
Objective To evaluate the impact of 3-dimensional ordered subset expectation maximization (3D-OSEM),2-dimensional ordered subset expectation maximization (2D-OSEM),filtered-back projection (FBP),and the number of OSEM iterations and subsets on quantitative results in SPECT/CT.Methods A Jaszczak cylindrical phantom and NEMA/IEC body phantom were performed in routine SPECT/CT using CT attenuation correction,scatter correction and 3D-OSEM reconstructed image.The system volume sensitivity (cpm/kBq) was acquired from the reconstructed image of Jaszczak phantom,and the absolute activity concentration (kBq/ml) of the hot sphere from IEC phantom was calculated and compared with true activity concentration,then quantitative error was calculated.With changing the reconstruction algorithm (2D-OSEM,FBP) and OSEM reconstruction parameters (number of iterations and subsets) to reconstruct the IEC phantom,the differences of quantitative results from different reconstruction algorithms and OSEM iterations and subsets were compared.Results When reconstructing images with 3D-OSEM,2D-OSEM and FBP,the quantitative error of each sphere increased with the decrease of the spherical volume (r=-0.831,-0.831,-0.826,all P<0.05).The quantitative error of different volume spheres among three reconstruction algorithms was statistically significant (F=8.850,P<0.05).Among them,the result of 3D-OSEM was less than that of 2D-OS EM (P<0.05),and of 2D-OSEM was less than of FBP (P<0.05).The quantitative error of different volume spheres decreased with the increasing of number of iterations (r=-0.721,-0.681,-0.691,-0.711,-0.845,-0.893,all P<0.05) and decreased with the increase of number of subsets (r=-0.670,-0.694,-0.717,-0.852,-0.956,-0.998,all P<0.05).Conclusion The quantitative accuracy of 3D-OSEM reconstruction based on CT attenuation correction and scattering correction is significantly better than that of 2D-OSEM and FBP.Choosing the appropriate OSEM reconstruction parameters is helpful to improve the quantification accuracy in SPECT/CT.
7.Absolute quantitative phantom of SPECT/CT imaging based on specified reconstruction algorithms and correction methods
Kemin HUANG ; Yanlin FENG ; Weitang LIANG ; Lin LI ; Yexia FENG ; Dalang DENG
Chinese Journal of Nuclear Medicine and Molecular Imaging 2018;38(5):340-344
Objective To investigate the methodology for absolute quantification with SPECT/CT using specified reconstruction algorithms and correction methods,and to determine the influence factors for quantitative accuracy.Methods The routine SPECT/CT imaging were performed with Jaszczak cylindrical phantom and International Electrotechnical Conmission (IEC) body phantom using a given acquisition and reconstruction parameter.The system volume sensitivities(SvoI)were acquired from the reconstructed images of Jaszczak phantom study.The absolute radioactivity of the hot spheres from IEC phantom study was calculated,and then the quantitative accuracies were checked.Differences of absolute quantitative value on quantitative accuracy were compared between 3 dimensional (3D)-ordered-subsets expectation maximization (OSEM) and 2 dimensional (2D)-OSEM,CT attenuation correction (AC) and no attenuation correction (NOAC),scatter correction (SC) and no scatter correction (NOSC),partial volume effect (PVE) correction and no PVE correction.Two-sample t test,one-way analysis of variance and Pearson correlation analysis were used.Results When 3D-OSEM,CTAC,SC and PVE correction were used,the average difference between absolute quantitative value and true value (374 kBq/ml) was-2.49% in 6 hot spheres,and there was no obvious correlation between the quantitative error and the spheres volume (r=-0.795,P>0.05).In the absence of PVE correction,the quantitative error of each sphere increased with the decrease of sphere volume (r=-0.852,P<0.05).Differences of the quantitative value and the true value for 6 hot spheres among different reconstruction/correction methods were statistically significant (F =826.631,P<0.05).The difference was smaller in 3D-OSEM+CTAC+NOSC than that in 2D-OSEM+CTAC+NOSC:(52.83±13.79) vs (61.33 ± 15.00) k Bq/ml (P<0.05).The similar results were found when comparing differences between 3DOSEM+CTAC+SC and 3D-OSEM+CTAC+NOSC,also between 3D-OSEM+CTAC+NOSC and 3D-OSEM+ NOAC+NOSC:(9.33±5.47) vs (52.83±13.79) kBq/ml,(52.83±13.79) vs (307.66±9.24) kBq/ml (both P<0.05).Conclusions An accurate absolute quantitative value could be obtained with 3D-OSEM reconstruction algorithm,CTAC,SC and PVE correction in SPECT/CT imaging.
8.Phantom study of the influence of time of flight and point spread function on PET/CT image quality and standardized uptake value
Kemin HUANG ; Yanlin FENG ; Weitang LIANG ; Lin LI ; Dalang DENG ; Weiping HE ; Yexia FENG
Chinese Journal of Nuclear Medicine and Molecular Imaging 2021;41(7):420-424
Objective:To explore the influence of time of flight (TOF) and point spread function (PSF) on PET/CT image quality and standardized uptake value (SUV) based on a phantom study.Methods:PET/CT imaging were performed using Jaszczak phantom and International Electrotechnical Commission (IEC) body phantom respectively, and conventional clinical imaging protocol (3 min/bed) was used for three consecutive imaging. The ordered subsets expectation maximization (OSEM), OSEM+ TOF, OSEM+ PSF and OSEM+ TOF+ PSF were used to reconstruct the raw data respectively. The differences of image resolution, image uniformity, contrast, signal to noise ratio (SNR) and SUV among different reconstruction algorithms were compared by using one-way analysis of variance and the least significant difference (LSD) t test. The correlations between SNR, mean SUV (SUV mean), maximum SUV (SUV max) and the sphere diameter were analyzed by Pearson correlation analysis. Results:The minimum image resolution for the hot column was 6.4 mm by OSEM and OSEM+ PSF reconstruction, while it was 4.8 mm by OSEM+ TOF and OSEM+ TOF+ PSF reconstruction. The contrast was significantly better by OSEM+ TOF ((78.56±1.21)%) and OSEM+ TOF+ PSF ((78.85±1.17)%) reconstruction than that by OSEM reconstruction ((73.44±1.47)%; F=61.068, t values: 9.503, 10.018, both P<0.001). The maximum and minimum nonuniformity percentages were significantly better for images reconstructed with OSEM+ PSF than those reconstructed with OSEM ( F values: 10.286, 27.630, t values: -2.599, 7.698, both P<0.05). In IEC phantom imaging, the SNR and SUV max of hot sphere were higher by OSEM+ PSF and OSEM+ TOF+ PSF reconstruction than those by OSEM reconstruction (SNR: (98.99±34.76)%, (98.29±28.66)%, (73.64±26.05)%; F=5.712, t values: 3.209, 3.412, both P<0.05; SUV max: 8.96±2.72, 9.28±2.17, 8.01±2.21; F=3.931, t values: 2.154, 2.863, both P<0.05), but there was no significant difference between OSEM+ TOF and OSEM reconstruction ( t values: 0.297, 0.272, both P>0.05). Among the four reconstruction methods, the SNR and SUV mean increased with the increase of the sphere diameter ( r values: 0.913-0.963, all P<0.05), but SUV max in images reconstructed with OSEM+ PSF and OSEM+ TOF+ PSF had no significant correlations with the sphere diameter ( r values: 0.496, 0.614, both P>0.05). Conclusions:Under specific acquisition and reconstruction conditions, TOF mainly improves image resolution and contrast, while PSF mainly improves image uniformity and SNR. The combination of the two method can obtain better image quality and significantly improve the SUV of hot lesions.
9.Impact of Partial Volume Effect on Quantitative Results in SPECT/CT
Kemin HUANG ; Yanlin FENG ; Weitang LIANG ; Lin LI ; Yexia FENG ; Dalang DENG ; Weiping HE
Chinese Journal of Medical Imaging 2017;25(11):867-871
Purpose The partial volume effect is a main factor to impact the image quality and the accuracy of the quantitative analysis of nuclear medicine image.The aim of this study is to evaluate the effects of partial volume effect on quantitative result in SPECT/CT.Materials and Methods A Jaszczak cylindrical phantom and IEC body phantom were performed with routine SPECT/CT imaging using CT attenuation correction,scatter correction and three-dimensional ordered subset expectation maximization (3D-OSEM) reconstruct image.The system volume sensitivity (cpm/kBq) were acquired from the reconstructed image of Jaszczak phantom study.The absolute activity concentration (kBq /ml) of the hot sphere was calculated according to the IEC phantom study that the intensity of radioactivity had been measured in the dose calibrator,then checking computations the quantitative accuracy of all.The difference of quantitative accuracies from the different volume hot sphere was compared tusing a given acquisition and reconstruction parameter.The effects of volume of interest (VOI),target-to-background ratio (TBR) and acquisition time on quantitative accuracy were evaluated.Results CT attenuation correction and scatter correction,the difference of absolute activity and true activity value was obviously correlation with the sphere size by using 3D-OSEM.The quantitative errors were decreased along with the increased of sphere size (r=-0.844,P<0.05).The quantitative accuracy were significantly affected by the VOI size in the 1.15-11.49 ml sphere.It was obviously lower in the limbic of sphere than that in the center of sphere.And the quantitative errors were decreased along with the decreased of VOI size (r=0.999,0.992,0.994 and 0.767,P<0.05).However,the quantitative error was no obviously correlation with the VOI size (r=0.348,0.478,P>0.05) in the 26.52 ml and 0.52 ml sphere.The average quantitative error was lower in high TBR imaging (44.19%) than that in low TBR imaging (-46.18%),and it was lower in 20 s/frame imaging (-44.33%) than that in 10 s/frame imaging (-46.04%).Conclusion The quantitative accurate could be obviously affected by the partial volume effect in SPECT/CT imaging,exceptionally in the small lesions and the limbic of lesions.
10.Quantitative measurement of standardized uptake value of lumbar vertebra by 99Tcm-MDP bone imaging with SPECT/CT
Kemin HUANG ; Yanlin FENG ; Weitang LIANG ; Lin LI ; Yexia FENG ; Dalang DENG ; Weiping HE
Chinese Journal of Nuclear Medicine and Molecular Imaging 2019;39(4):227-230
Objective To explore the quantitative determination of standardized uptake value(SUV)of lumbar vertebra by 99Tcm-methylene diphosphonate(MDP)bone imaging with SPECT/CT.Methods A total of 90 patients(16 males,74 females,age:(60.0±11.2)years)who underwent 99Tcm-MDP bone imaging and local lumbar SPECT/CT imaging from May 2017 to November 2017 were retrospectively analyzed.CT attenuation correction,scatter correction and 3-dimensional ordered subset expectation maximization(3D-OSEM)reconstruction were used.The radioactive counts of lumbar vertebra LL-L4 in patients with high MDP-uptake(including degenerative changes and bone metastases)and patients with non-high MDP-uptake(including osteoporosis and non-osteoporosis)were measured.Basing on that,the radioactivity of unit volume in lumbar and lesion was calculated and converted to SUV.The difference of SUV for lumbar and lesions from different types of patients was analyzed,and the correlation between lumbar SUV and varies of parameters were also analyzed.Data were analyzed by two-sample t test and Pearson correlation analysis.Results The mean SUV(SUVmean)and maximum SUV(SUVmax)of L1-L4 in 54 patients with non-high MDP-uptake were 4.64±1.03 and 7.09±1.61 respectively.They were positively correlated with bone mineral content,CT value and body weight(r values:0.433-0.700,all P<0.05),and negatively correlated with age(r values;-0.514 and -0.456,both P<0.001).The SUVmean and SUVmax of patients with osteoporosis were 3.81±0.76 and 5.86±1.34 respectively,which were significantly lower than those of non-osteoporosis(5.13±0.84 and7.82±1.30;t values:-5.892 and-5.240,both P<0.001).The SUVmean and SUVmax of 37 metastases were 16.40±6.07 and 24.25±11.35 respectively in 16 patients,which were significantly higher than those in patients with degenerative changes(20 patients with 27 lesions;9.30±3.16 and 13.48±5.21;t values:6.074 and 5.083,both P<0.001).Conclusion Based on the specific reconstruction algorithm and correction method,the SUV of lumbar vertebra on 99Tcm-MDP SPECT/CT bone imaging can be obtained,and the bone mineral metabolism can be reflected.