Applicability of [18F]FDG/PET for investigating rosmarinic acid preconditioning efficacy in a global stroke model in mice

ABSTRACT Positron emission tomography (PET) is a non-invasive nuclear imaging technique that uses radiotracers to track cell activity. The radiopharmaceutical 18F-fluoro-2-deoxyglucose ([18F] FDG) is most commonly used in nuclear medicine for the diagnosis of various diseases, including stroke. A stroke is a serious condition with high mortality and morbidity rates. Rosmarinic acid (RA) is a promising therapeutic agent that exerts neuroprotective effects against various neurological diseases. Therefore, this study aimed to evaluate the applicability of [18F]FDG/PET for investigating the neuroprotective effects of RA in case of a global stroke model in mice. The [18F]FDG/PET technique facilitates the observation of ischemia and reperfusion injuries in the brain. Moreover, the recovery of glucose metabolism in three specific brain regions, the striatum, superior colliculus, and inferior colliculus, was observed after preconditioning with RA. It was concluded that the [18F]FDG/PET technique may be useful for stroke diagnosis and the assessment of treatment response. In addition, a long-term longitudinal study using biochemical analysis in conjunction with functional imaging may provide further conclusive results regarding the effect of RA on cerebral ischemia.

Construction and verification of RNA interfering lentiviral vector targeting Suv39h1 gene / 中国职业医学

OBJECTIVE: To construct the RNA interference(RNAi) lentiviral vector of suppressor of variegation 3-9 homolog 1(Suv39 h1) and verify its interfering efficiency by transfecting it to the bone marrow-derived mesenchymal stem cells(BMSCs). METHODS: The oligonucleotides of RNA plasmid were designed and synthesized according to the gene sequence of Suv39 h1 and short hairpin RNA design principles. Three kinds of LV-Suv39 h1-RNAi recombinant plasmids with different lentivirus knockdown targets(KD1, KD2 and KD3) were constructed. After identification by restriction analysis and sequencing, the packaged lentivirus vectors with the three kinds of Suv39 h1 gene were transfected into rat BMSCs at logarithmic growth stage, and were named KD1, KD2 and KD3 transfection groups. The control group was transfected with the negative control virus. After 72 hours transfection, the transfection efficiency was evaluated, and the relative mRNA levels of Suv39 h1 were determined by quantitative real-time polymerase chain reaction(qPCR). RESULTS: Sequencing analysis demonstrated that three kinds of LV-Suv39 h1-RNAi recombinant plasmids were constructed correctly. The results of transfection efficiency evaluation showed that more than 80.00% green fluorescence was expressed in the BMSCs transfected with the three lentiviral vectors with a multiplicity of infection of 20. These results indicated that lentivirus was successfully constructed and transfection efficiency was high. The results of qPCR showed that the relative expression of Suv39 h1 mRNA in BMSCs of KD1, KD2 and KD3 transfection groups was lower than that in the control group(all P<0.05), and the relative expression of Suv39 h1 mRNA in KD1 and KD3 transfection groups was lower than that in KD2 transfection group(both P<0.05). However, there was no significant difference in the relative expression of Suv39 h1 mRNA between KD1 and KD3 transfection groups(P>0.05). CONCLUSION: The constructed lentiviral vector with low expression of Suv39 h1 was constructed successfully. This vector can be expressed in rat BMSCs, which lays a foundation to study the effect of Suv39 h1 gene in acute myeloid leukemia.

Limb Deformity Correction Using the Ortho SUV Frame

@#BACKGROUND AND OBJECTIVE: Limb deformity in terms of length discrepancy, angular and rotational deformities are amenable to correction using the Ilizarov method. The corrections can be achieved using the Ortho SUV Frame (OSF), a computer assisted six axes external fixator. Previous studies have reported easier and more accurate deformity correction. In this study, we report on our initial experience and treatment outcomes in using this system. MATERIALS AND METHODS: This study is a case series of patients where the Ilizarov circular frame was applied and which the deformity correction was carried out using the OSF. Success and accuracy in correction, length of time to correct, number of revisions needed and complications were gathered from a review of medical records. RESULTS: Thirty limbs in twenty nine cases were included in this report. Seventy seven percent (23/30) of the deformities were due to previous trauma. The rest were due to Blounts, infection and tumor. Correction in eighty seven percent (26/30) were achieved using the turning schedule provided by the Ortho SUV application software. Three cases required surgical removal of soft tissue interposition before further correction using the software was achieved. One case with posterior translation underwent closed manipulation. In the end all planned deformity corrections were achieved. Complications included pin tract swelling and erythema in 13% and all resolved either with oral antibiotics alone or combined with surgical release of pin sites under local anesthesia. CONCLUSION: The Ortho SUV is an effective tool to carry out deformity corrections using the Ilizarov method.

SUV39H1 deficiency suppresses clear cell renal cell carcinoma growth by inducing ferroptosis

Clear cell renal cell carcinoma (ccRCC) is a common kidney malignancy characterized by a poor prognosis. Suppressor of variegation 3-9 homolog 1 (

Correlation of PET/CT metabolic makers with expression of immune cell markers in patients with lung adenocarcinoma / 中国肿瘤生物治疗杂志

@#[Abstract] Objective: To investigate the relationship between 18F-FDG PET/CT metabolic indicators and expression of immunocyte markers in lung adenocarcinoma patients, and to explore its significance in treatment and prognosis prediction for lung adenocarcinoma patients.Methods:Theclinicaldataof85lungadenocarcinomapatients,whoadmittedtoTianjinMedicalUniversityCancerInstituteand Hospital and underwent PET/CT examination from April 2008 to August 2014, were retrospectively analyzed. The expression levels of CD3, CD8, CD68, CD163, CD11c, Foxp3, PD-1 and PD-L1 were determined by immunohistochemistry. Correlations among immune markers (CD68+TAM), PET/CT metabolic parameters (SUVmax, SUVpeak and SUVmean) and tumor metabolic indicators (MTV , TLG) were analyzed using Pearson correlation analysis.The relationships between tumor metabolism, immune indicators and patients’survival outcomes were analyzed using the Kaplan-Meier method. Results: There was a remarkably negative correlation between SUVmax, SUVpeak, SUVmean and expression level of CD68+TAMs(r=-0.253,-0.265,-0.263,allP<0.05)butpositivecorrelationwithPD-1+TILs (r=0.427, 0.402, 0.395, all P<0.01) in lung adenocarcinoma patients. MTV and TLG were positively associated with Foxp3+ Tregs and PD-1+ TILs (r=0.313, 0.307, 0.29, 0.407, all P<0.01). Kaplan-Meier survival analysis showed that SUVmax, SUVmean, CD11c+DCs, PD-L1+ cells and TLG were all significantly associated with patients’prognosis (PFS or OS) (all P<0.05). Conclusion: Metabolism of tumor primary lesions is significantly correlated with tumor infiltrating immunocytes, and some of these indicators were associatedwithpatients’prognosis, suggesting that tumor metabolism and microenvironment immune status reflected by 18F-FDG PET/CTindicatorsmay have important reference value fortheimmunotherapyandprognosispredictionoflungadenocarcinoma patients.

Comparison of different quantification methods for 18F-fluorodeoxyglucose-positron emission tomography studies in rat brains

OBJECTIVES: This study aimed to evaluate several methods to estimate glucose consumption in the male Wister rat brain as measured by PET. METHODS: Fourteen male Wistar normoglycemic rats were studied. The input function consisted of seventeen blood samples drawn manually from the femoral artery. Glucose uptake values were calculated using the input function resulting from the arterial blood samples and the tissue time-activity curve derived from the PET images. The estimated glucose consumption rate (Ki) based on the 2-tissue compartment model (2TCM) served as the standard for comparisons with the values calculated by the Patlak analysis and with the fractional uptake rate (FUR), standardized uptake value (SUV) and glucose corrected SUV (SUVglu). RESULTS: No significant difference between the standard Ki and the Patlak Ki was observed. The standard Ki was also found to have strong correlations and concordance with the Ki value estimated by the Patlak analysis. The FUR method presented an excellent correlation with the Ki value obtained by the 2TCM/Patlak analyses, in contrast to the SUV or SUVglu. CONCLUSIONS: From a methodological point of view, the present findings confirm the theoretical limitations of the cerebral SUV and SUVglu as a substitute for Ki in the estimation of glucose consumption in the brain. Our data suggest that the FUR is the surrogate to Ki.

Suppressor of Variegation 3–9 Homolog 2, a Novel Binding Protein of Translationally Controlled Tumor Protein, Regulates Cancer Cell Proliferation

Suppressor of Variegation 3–9 Homolog 2 (SUV39H2) methylates the lysine 9 residue of histone H3 and induces heterochromatin formation, resulting in transcriptional repression or silencing of target genes. SUV39H1 and SUV39H2 have a role in embryonic development, and SUV39H1 was shown to suppress cell cycle progression associated with Rb. However, the function of human SUV39H2 has not been extensively studied. We observed that forced expression of SUV39H2 decreased cell proliferation by inducing G1 cell cycle arrest. In addition, SUV39H2 was degraded through the ubiquitin-proteasomal pathway. Using yeast two-hybrid screening to address the degradation mechanism and function of SUV39H2, we identified translationally controlled tumor protein (TCTP) as an SUV39H2-interacting molecule. Mapping of the interacting regions indicated that the N-terminal 60 amino acids (aa) of full-length SUV39H2 and the C-terminus of TCTP (120–172 aa) were critical for binding. The interaction of SUV39H2 and TCTP was further confirmed by co-immunoprecipitation and immunofluorescence staining for colocalization. Moreover, depletion of TCTP by RNAi led to up-regulation of SUV39H2 protein, while TCTP overexpression reduced SUV39H2 protein level. The half-life of SUV39H2 protein was significantly extended upon TCTP depletion. These results clearly indicate that TCTP negatively regulates the expression of SUV39H2 post-translationally. Furthermore, SUV39H2 induced apoptotic cell death in TCTP-knockdown cells. Taken together, we identified SUV39H2, as a novel target protein of TCTP and demonstrated that SUV39H2 regulates cell proliferation of lung cancer cells.

The usefulness of fluorodeoxyglucose-PET/CT for preoperative evaluation of ductal carcinoma in situ

PURPOSE: PET/CT is useful in preoperative evaluation of invasive breast cancer (IBC) to predict axillary metastasis and staging workup. The usefulness is unclear in cases of ductal carcinoma in situ (DCIS) diagnosed at biopsy before surgery, which sometimes is upgraded to IBC after definitive surgery. The aim of this study is to find out the usefulness of PET/CT on DCIS as a preoperative evaluation tool. METHODS: We investigated 102 patients preoperatively diagnosed with DCIS who subsequently underwent definitive surgery between 2010 and 2015. The uptake of 18F-fluorodeoxyglucose was graded by visual and semiquantitative methods. We analyzed the maximum standardized uptake value (SUVmax) of each patient with clinicopathologic variables. We determined optimal cutoff values for SUVmax by receiver operating characteristic curve analysis. RESULTS: Fifteen cases out of 102 cases (14.7%) were upgraded to IBC after surgery. The SUVmax was higher in patients upgraded to IBC (mean: 2.56 vs. 1.36) (P = 0.007). The SUVmax was significantly higher in patients who had symptoms, palpable masses, lesions over 2 cm in size and BI-RAD category 5. Both visual and semiquantitative analysis were significant predictors of IBC underestimation. SUVmax of 2.65 was the theoretical cutoff value in ROC curve analysis in predicting the underestimation of IBC. The underestimation rate was significantly higher in patients with SUVmax >2.65 (P < 0.001), over the moderate enhanced uptake on visual analysis (P < 0.001). CONCLUSION: PET/CT can be used as a complementary evaluation tool to predict the underestimation of DCIS combined with the lesion size, palpable mass, symptomatic lesion, and BI-RAD category.

Value of 18F-FDG PET/CT in diagnosis of single space-occupying lesion of the liver / 中国肿瘤临床

Objective: To evaluate the diagnostic value of PET/CT in single space-occupying lesion of the liver hepatic disease. Meth-ods: Data of 177 patients from Tianjin Medical University Cancer Institute and Hospital between March 2012 and September 2017 with a single hepatic space-occupying lesion who had undergone 18F-FDG PET/CT were collected. CT values and the long and short di-ameters were measured in PACS system. A post-processing workstation was employed, and PETVCAR software was used to automati-cally measure the standardized uptake value (SUV) of the focal and the normal liver tissue. Afterward, T (SUV of the focal)/N (SUV of the normal liver tissue) ratios were calculated. Then, the diagnostic value of various parameters for different pathological types was an-alyzed. The correlation between two continuous variables was calculated using Pearson analysis. Results: The long and short diame-ters of the primary hepatic carcinoma were significantly larger than those of metastatic lesions (P<0.05). The positive rates of hepato-cellular carcinoma (HCC), intrahepatic cholangiocarcinoma (ICC), and metastases were 67.6%, 95.2%, and 98.7%, respectively. All meta-bolic parameters of HCC were significantly lower than those of the other pathological types of liver cancer or metastases (P<0.05). The AUCs for diagnosis of ICC and metastases were higher than 0.5, but there was no statistical difference between the AUCs of different SUVs. Moreover, SUVmax was related to lesion size (r=0.535, P<0.001). Conclusions: 18F-FDG PET/CT has a high positive predictive val-ue and effective diagnostic function for ICC and metastasis, and the diagnostic efficacy for both is higher than that for HCC.

Prognostic value of nodal SUVmax of 18F-FDG PET/CT in nasopharyngeal carcinoma treated with intensity-modulated radiotherapy

PURPOSE: To investigate the predictive role of maximum standardized uptake value (SUVmax) of 2-[18F]fluoro-2-deoxy-D-glucose (18F-FDG) positron emission tomography/computed tomography (PET/CT) in nasopharyngeal cancer patients treated with intensity-modulated radiotherapy (IMRT). MATERIALS AND METHODS: Between October 2006 and April 2016, 53 patients were treated with IMRT in two institutions and their PET/CT at the time of diagnosis was reviewed. The SUVmax of their nasopharyngeal lesions and metastatic lymph nodes (LN) was recorded. IMRT was delivered using helical tomotherapy. All patients except for one were treated with concurrent chemoradiation therapy (CCRT). Correlations between SUVmax and patients’ survival and recurrence were analyzed. RESULTS: At a median follow-up time of 31.5 months (range, 3.4 to 98.7 months), the 3-year overall survival (OS) and disease-free survival (DFS) rates were 83.2% and 77.5%, respectively. In univariate analysis, patients with a higher nodal pre-treatment SUVmax (≥ 13.4) demonstrated significantly lower 3-year OS (93.1% vs. 55.5%; p = 0.003), DFS (92.7% vs. 38.5%; p < 0.001), locoregional recurrence-free survival (100% vs. 50.5%; p < 0.001), and distant metastasis-free survival (100% vs. 69.2%; p = 0.004), respectively. In multivariate analysis, high pre-treatment nodal SUVmax (≥ 13.4) was a negative prognostic factor for OS (hazard ratio [HR], 7.799; 95% confidence interval [CI], 1.506–40.397; p = 0.014) and DFS (HR, 9.392; 95% CI, 1.989–44.339; p = 0.005). CONCLUSIONS: High pre-treatment nodal SUVmax was an independent prognosticator of survival and disease progression in nasopharyngeal carcinoma patients treated with IMRT in our cohort. Therefore, nodal SUVmax may provide important information for identifying patients who require more aggressive treatment.

Ratio of Mediastinal Lymph Node SUV to Primary Tumor SUV in ¹⁸F-FDG PET/CT for Nodal Staging in Non-Small-Cell Lung Cancer / 대한핵의학회잡지

PURPOSE: Following determination of the maximum standardized uptake values (SUVmax) of the mediastinal lymph nodes (SUV-LN) and of the primary tumor (SUV-T) on ¹⁸F-FDG PET/CT in patients with non-small-cell lung cancer (NSCLC), the aim of the study was to determine the value of the SUV-LN/SUV-T ratio in lymph node staging in comparison with that of SUV-LN.METHODS: We retrospectively reviewed a total of 289 mediastinal lymph node stations from 98 patients with NSCLC who were examined preoperatively for staging and subsequently underwent pathologic studies of the mediastinal lymph nodes. We determined SUV-LN and SUV-R for each lymph node station on ¹⁸F-FDG PET/CT and then classified each station into one of three groups based on SUV-T (low, medium and high SUV-T groups). Diagnostic performance was assessed based on receiver operating characteristic (ROC) curve analysis, and the optimal cut-off values that would best discriminate metastatic from benign lymph nodes were determined for each method.RESULTS: The average of SUV-R of malignant lymph nodes was significantly higher than that of benign lymph nodes (0.79±0.45 vs. 0.36±0.23, P<0.0001). In the ROC curve analysis, the area under the curve (AUC) of SUV-R was significantly higher than that of SUV-LN in the low SUV-T group (0.885 vs. 0.810, P= 0.019). There were no significant differences between the AUCs of SUV-LN and of SUV-R in the medium and high SUV-T groups. The optimal cut-off value for SUV-R in the low SUV-T group was 0.71 (sensitivity 87.5 %, specificity 85.9 %).CONCLUSIONS: The SUV-R performed well in distinguishing between metastatic and benign lymph nodes. In particular, SUV-R was found to have a better diagnostic performance than SUV-LN in the low SUV-T group.

Primary Pulmonary Lymphoepithelioma-like Carcinoma on FDG PET/CT / 대한핵의학회잡지

A 69-year-old male smoker was referred to ¹⁸F-f luorodeoxyglucose (FDG) pos i t r on emi s sion tomography-computed tomography (PET/CT) with the indication of a suspicious solitary pulmonary nodule. FDG PET/CT determined a 2.5 × 2-cm soft-tissue lesion (SUVmax, 16.2) with spiculated margins in the hilum of the right lung. A 1-cm diameter lymphadenopathy on the right hilum with an SUVmax of 3.2 was also determined. Transbronchial biopsy of the right hilar lymphadenopathy did not reveal any malignant features in histopathologic examination, and it was determined to be reactive. The patient underwent a right upper lobe segmentectomy, and the histopathologic evaluation revealed that the tumor was a primary lymphoepithelioma-like carcinoma (LELC) of the lung with negative Epstein-Barr virus (EBV) on in situ hybridization studies. In this case report, we mainly focus on the FDG avidity of this very rare kind of tumor comparatively with previous reports and possible explanations of discordancy in FDG avidity in relation to histopathologic characteristics.

Value of 18F-FDG PET/CT with Volume Metabolic Parameters for Prognosis Evaluation in Limited-Disease Small Cell Lung Cancer / 中山大学学报(医学科学版)

[Objective]To investigate the prognostic value of 18F-FDG PET/CT with different metabolic parameters in newly diagnosed limited-disease(LD)small cell lung cancer(SCLC).[Methods]Retrospective analysis was carried out in the patients between June 2005 to December 2016 in our hospital confirmed of LD SCLC by pathology or cytology and comprehensive imaging. Fifty-four patients were recruited. Record the general characteristics of patients,pre-treatment KPS score,smoking status,weight loss,serum LDH,NSE,OS,PFS. All lesions(primary lesions + metastases)were sketched out within one VOI,and the SUVmax, SUVmean and SUVpeak in the VOI were automatically measured and recorded. The automatic measurement was performed by the fixed threshold method. The thresholds of tumor of MTV and TLG were 40% and 50% of SUVmax. The TLG and MTV were identified as TLG40%,TLG50%,MTV40% and MTV50% respectively. Kaplan-Meier method was used for survival analysis. All the prognostic factors were analyzed by Cox model.[Result]The median SUVmax was 13.92(2.61~43.28),the median of SUVmean was 8.31(1.71~26.85) and the median of SUVpeak was 10.51(1.49 ~ 27.48). The median of TLG40% was 340.22(16.58 ~ 2827.26),the median of TLG50%was 215.645(1.70 ~ 2270.36),the median of MTV40% was 36.71(1.15 ~ 259.47 cm3),the median of MTV50% was 19.65(0.93 ~1900.00)cm3. Univariate and multivariate analysis of metabolic index and prognosis showed that TLG50% was the prognostic factor of OS(P = 0.013),but not of PFS(P > 0.05). The SUVmax,SUVmean and SUVpeak were not the prognostic factors of OS and PFS(P >0.05).[Conclusion]The volume metabolic parameters TLG50%was the independent prognostic factor of the overall survival time of the LD SCLC. The volume metabolic parameters (TLG and MTV) of 18F-FDG PET/CT were related to the prognosis of SCLC ,which could provide the basis for individual chemotherapy.

Predictive significance of standardized uptake value parameters of FDG-PET in patients with non-small cell lung carcinoma

18F-fluoro-2-deoxyglucose (FDG) positron emission tomography (PET)/computed tomography (CT) is widely used to diagnose and stage non-small cell lung cancer (NSCLC). The aim of this retrospective study was to evaluate the predictive ability of different FDG standardized uptake values (SUVs) in 74 patients with newly diagnosed NSCLC. 18F-FDG PET/CT scans were performed and different SUV parameters (SUVmax, SUVavg, SUVT/L, and SUVT/A) obtained, and their relationship with clinical characteristics were investigated. Meanwhile, correlation and multiple stepwise regression analyses were performed to determine the primary predictor of SUVs for NSCLC. Age, gender, and tumor size significantly affected SUV parameters. The mean SUVs of squamous cell carcinoma were higher than those of adenocarcinoma. Poorly differentiated tumors exhibited higher SUVs than well-differentiated ones. Further analyses based on the pathologic type revealed that the SUVmax, SUVavg, and SUVT/L of poorly differentiated adenocarcinoma tumors were higher than those of moderately or well-differentiated tumors. Among these four SUV parameters, SUVT/L was the primary predictor for tumor differentiation. However, in adenocarcinoma, SUVmax was the determining factor for tumor differentiation. Our results showed that these four SUV parameters had predictive significance related to NSCLC tumor differentiation; SUVT/L appeared to be most useful overall, but SUVmax was the best index for adenocarcinoma tumor differentiation.

Comparison of standardized uptake values measured on 18F-NaF PET/CT scans using three different tube current intensities / Comparação dos valores de captação medidos nos estudos de 18F-NaF PET/CT utilizando três intensidades diferentes de corrente do tubo de tomografia computadorizada

Objective: To analyze standardized uptake values (SUVs) using three different tube current intensities for attenuation correction on 18FNaF PET/CT scans. Materials and Methods: A total of 254 18F-NaF PET/CT studies were analyzed using 10, 20 and 30 mAs. The SUVs were calculated in volumes of interest (VOIs) drawn on three skeletal regions, namely, right proximal humeral diaphysis (RH), right proximal femoral diaphysis (RF), and first lumbar vertebra (LV1) in a total of 712 VOIs. The analyses covered 675 regions classified as normal (236 RH, 232 RF, and 207 LV1). Results: Mean SUV for each skeletal region was 3.8, 5.4 and 14.4 for RH, RF, and LV1, respectively. As the studies were grouped according to mAs value, the mean SUV values were 3.8, 3.9 and 3.7 for 10, 20 and 30 mAs, respectively, in the RH region; 5.4, 5.5 and 5.4 for 10, 20 and 30 mAs, respectively, in the RF region; 13.8, 14.9 and 14.5 for 10, 20 and 30 mAs, respectively, in the LV1 region. Conclusion: The three tube current values yielded similar results for SUV calculation. .

Objetivo: Analisar os valores de captação (SUVs) utilizando três diferentes intensidades de mAs para realização de correção de atenuação na 18F-NaF PET/CT. Materiais e Métodos: Um total de 254 exames de 18F-NaF PET/CT foi estudado utilizando 10, 20 e 30 mAs. Os SUVs foram calculados utilizando volumes de interesse (VOIs) desenhados em três regiões do esqueleto: diáfise proximal do úmero direito (UD), diáfise proximal do fêmur direito (FD) e primeira vértebra lombar (VB1), totalizando 712 VOIs. Desse total, 675 regiões classificadas como normal foram analisadas (236, 232 e 207 na UD, FD e VB1, respectivamente). Resultados: A média dos SUVs para cada região óssea foi 3,8, 5,4 e 14,4 para UD, FD e VB1, respectivamente. Quando os exames foram agrupados pelo valor da corrente mAs, a média de valores de captação foi 3,8, 3,9 e 3,7 para 10, 20 e 30 mAs, respectivamente, na UD; 5,4, 5,5 e 5,4 para 10, 20 e 30 mAs, respectivamente, na FD; e 13,8, 14,9 e 14,5 para 10, 20 e 30 mAs, respectivamente, na VB1. Conclusão: As três correntes analizadas apresentaram resultados similares para o cálculo de SUV. .

Evaluation of changes in lipid peroxidation, ROS production, surface structures, secondary metabolites and yield of linseed (Linum usitatissimum L.) under individual and combined stress of ultraviolet-B and ozone using open top chambers.

The individual and interactive effects of supplemental UV-B (sUV-B) (ambient + 7.2 kJ m-2 d-1) and elevated O3 (ambient + 10 ppb) were evaluated under field conditions using open top chambers on two cultivars, Padmini and T-397 of linseed (Linum usitatissimum L.). Mean monthly surface level of O3 concentrations varied from 27.7 ppb to 59.0 ppb during the experimental period. Both UV-B and O3 induced the production of ROS (H2O2 and O2.-), resulting in significant damage of membranes due to lipid peroxidation and electrolyte leakage. Synthesis of secondary metabolites (flavonoids, anthocyanin, lignin and wax) was also enhanced in all the treatments, whereas biomass and yield were reduced. Alterations in frequency of stomata and wax distribution were also observed through scanning electron microscopy (SEM). Cultivar Padmini was found to be more sensitive because of higher damage of membrane vis-a-vis reduction in biomass and seed yield. However, concentrations of flavonoids, anthocyanin, lignin and wax were higher in T-397, suggesting its relative resistance against applied stress. Combined exposure of sUV-B and O3 was less harmful, as compared to their individual treatment. Among the three treatments, O3 was found to be more detrimental for overall growth and sUV-B for economic yield.

Prognostic Value of Volume-Based 18F-Fluorodeoxyglucose PET/CT Parameters in Patients with Clinically Node-Negative Oral Tongue Squamous Cell Carcinoma

OBJECTIVE: To evaluate the prognostic value of volume-based metabolic parameters measured with 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography (PET) in patients with clinically node-negative (cN0) oral tongue squamous cell carcinoma (OTSCC) as compared with other prognostic factors. MATERIALS AND METHODS: In this study, we included a total of 57 patients who had been diagnosed with cN0 tongue cancer by radiologic, 18F-FDG PET/CT, and physical examinations. The maximum standardized uptake value (SUVmax), average SUV (SUVavg), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) for primary tumors were measured with 18F-FDG PET. The prognostic significances of these parameters and other clinical variables were assessed by Cox proportional hazards regression analysis. RESULTS: In the univariate analysis, pathological node (pN) stage, American Joint Committee on Cancer (AJCC) stage, SUVmax, SUVavg, MTV, and TLG were significant predictors for survival. On a multivariate analysis, pN stage (hazard ratio = 10.555, p = 0.049), AJCC stage (hazard ratio = 13.220, p = 0.045), and MTV (hazard ratio = 2.698, p = 0.033) were significant prognostic factors in cN0 OTSCC patients. The patients with MTV > or = 7.78 cm3 showed a worse prognosis than those with MTV < 7.78 cm3 (p = 0.037). CONCLUSION: The MTV of primary tumor as a volumetric parameter of 18F-FDG PET, in addition to pN stage and AJCC stage, is an independent prognostic factor for survival in cN0 OTSCC.

Role of 18F-fluoro-2-deoxyglucose Positron Emission Tomography in Gastric GIST: Predicting Malignant Potential Pre-operatively

PURPOSE: It is difficult to obtain biopsies from gastrointestinal stromal tumors (GISTs) prior to surgery because GISTs are submucoal tumors, despite being the most common nonepithelial neoplasms of the gastrointestinal tract. Unlike anatomic imaging techniques, PET-CT, which is a molecular imaging tool, can be a useful technique for assessing tumor activity and predicting the malignant potential of certain tumors. Thus, we aimed to evaluate the usefulness of PET-CT as a pre-operative prognostic factor for GISTs by analyzing the correlation between the existing post-operative prognostic factors and the maximum SUV uptake (SUVmax) of pre-operative 18F-fluoro-2-deoxyglucose (FDG) PET-CT. MATERIALS AND METHODS: The study was conducted on 26 patients who were diagnosed with gastric GISTs and underwent surgery after being examined with pre-operative FDG PET-CT. An analysis of the correlation bewteen (i) NIH risk classfication and the Ki-67 proliferation index, which are post-operative prognostic factors, and (ii) the SUVmax of PET-CT, which is a pre-operative prognostic factor, was performed. RESULTS: There were significant correlations between (i) SUVmax and (ii) Ki-67 index, tumor size, mitotic count, and NIH risk group (r=0.854, 0.888, 0.791, and 0.756, respectively). The optimal cut-off value for SUVmax was 3.94 between "low-risk malignancy" and "high-risk malignancy" groups. The sensitivity and specificity of SUVmax for predicting the risk of malignancy were 85.7% and 94.7%, respectively. CONCLUSIONS: The SUVmax of PET-CT is associated with Ki-67 index, tumor size, mitotic count, and NIH classification. Therefore, it is believed that PET-CT is a relatively safe, non-invasive diagnostic tool for assessing malignant potential pre-operatively.

Evaluation of the Feasibility of Applying Metabolic Target Volume in 4D RT Using PET/CT Image / 의학물리

In this study, we evaluated feasibility of applying MTV (Metabolic Target Volume) to respiratory gated radiotherapy for more accurate treatment using various SUV (Standard Uptake Value) from PET images. We compared VOI (Volume of Interest) images from 50%, 30% and 5% SUV (standard uptake volume) from PET scan of an artificial target with GTV (Gross Tumor Volume) images defined by percentage of respiratory phase from 4D-CT scan for respiratory gated radiotherapy. It is found that the difference of VOI of 30% SUV is reduced noticeably comparing with that of 50% SUV in longitudinal direction with respect to total GTV of 4D-CT image. Difference of VOI of 30% SUV from 4D-PET image defined by respiratory phase from 25% inhalation to 25% exhalation, and GTV from 4D-CT with the same phase is shown below 0.6 cm in maximum. Thus, it is better to use 4D-PET images than conventional PET images for applying MTV to gated RT. From the result that VOI of 5% SUV from 4D-PET agrees well with reference image of 4D-CT in all direction, and the recommendation from department of nuclear medicine that 30% SUV be advised for defining tumor range, it is found that using less than 30% SUV will be more accurate and practical to apply MTV for respiratory gated radiotherapy.

The Value of 18-FDG PET CT in Soft Tissue Sarcoma / 대한정형외과학회잡지

PURPOSE: Recently, there have been many attempts to use PET-CT for the diagnosis of metastasis of soft tissue tumors and for differentiating benign tumors from malignant tumors. In this study, we wanted to evaluate the efficacy of 18-FDG PET CT in soft tissue tumors. MATERIALS AND METHODS: Patients (n=64) with suspected malignant soft tissue tumor had 18-FDG PET CT scans. This included 15 cases of benign soft tissue tumor, 34 cases of malignant soft tissue tumor and 15 cases of inflammatory lesions. All patients went through surgical treatment after PET-CT imaging was done, and all dissected tissues were biopsied. For semiquantitive analysis, SUVmax(Maximal standard uptake value) was measured, and SUVmax was determined using ROC analysis, the Kruskal-Wallis test and the Mann-Whitney test. RESULTS: Using 18-FDG PET CT it was possible to differentiate benign from malignant tumor using SUVmax values. But, discrimination between different grades of tumor was not possible. Also discrimination between malignant tumors and inflammatory lesions was not possible. CONCLUSION: PET-CT can be considered as a useful nuclear imaging method that can detect local recurrence and distant metastasis of soft tissue sarcoma and can differentiate benign from malignant tumors. But PET-CT results must be interpreted carefully in diagnoses when there is inflammatory disease or a suspected lesion present.