Objective To study bystander effect and cell death by HSV TK and ACV therapy on renal carcinoma cell lines GRC 1. Methods Different mix culture cells, which contained GRC 1/TK cells 0%、25%、50% and 100%,were treated with ACV 60 ?g/ml, the morphology and quantity of tumor cells being studied and checked with FCM and electron microscope. Results After exposure to ACV, GRC 1/TK cells, even only 25%, underwent cell death and bystander effect, but there was no obvious change in the morphology and quantity of GRC 1 cells exposed to ACV. Conclusions There were bystander effect and cell death on HSV TK and ACV therapy in renal carcinoma cell lines GRC 1. The mechanism of bystander effect may have deat with apoptosis.

Objective To assess the value of 18F-FDG PET/CT in clinical classification,monitoring of chemotherapeutic response and surveillance of histopathological transformation of Castleman's disease (CD).Methods Fourteen pathologically diagnosed CD patients (7 males,7 females; mean age:(45.64±14.30) years) were retrospectively reviewed.18F-FDG PET/CT was performed before chemotherapy in all patients and 4 of 14 patients were reexamined after the treatment.The study parameters included histopathological results,sites,number and highest SUVmax of the lesions.Mann-Whitney and Kruskal-Wallis tests were used for data analysis.Results Of all the 12 patients without histopathological transformation,one or more enlarged and metabolically active lymph nodes were found in each patient (SUVmax =3.94± 1.44,range:1.9-6.8),including 2 unicentric CD (UCD) and 10 multicentric CD (MCD).There was no statistically significant difference of SUVmam between UCD and MCD (4.55±3.18 vs 3.82±1.14; Z=0.22,P＞0.05).There was also no significant difference of SUVmax among different pathological types (hyaline-vascular CD (4/12):3.56±0.96,plasma cell CD (6/12):4.73±1.41,mixed CD (2/12):2.30±0.57; x2 =4.74,P＞0.05).For the 4 patients with follow-up PET/CT after chemotherapy,the lesion activity was normalized in 3 patients and clearly reduced in 1 patient.The SUVmax of 2 patients with histopathological transformation (10.85±2.05) was significantly higher than that without transformation (3.94± 1.44; Z=-2.19,P＜0.05).Conclusion 18F-FDG PET/CT may play an important role in clinical classification,monitoring of chemotherapeutic response and surveillance of histopathological transformation of CD.

Objective: To evaluate the diagnostic value of fluorine-18 fluorodeoxyglucose ( 18 F-FDG) positron emission tomography/computed tomography ( PET/CT) in fever of unknown origin ( FUO) in a Chinese hospital .Methods:The records of 51 patients with FUO (32 men and 19 women;mean age 54 years with a range between 3 and 81 years) were analyzed retrospectively .All the patients were examined by 18 F-FDG PET/CT scan and the results were compared with the final diagnosis which was established by additional procedures including pathology , laboratory examination , and clinical follow-up for more than 3 months.The t test was used for statistical analysis .Results: A final diagnosis was established for 48 patients , including 32 patients with infectious diseases , 9 with malignancies , and 7 with non-infectious inflammatory diseases .By FDG PET scan alone , the rates of true positive , false positive , false negative, and true negative were 52.9%, 27.5%, 17.6%, and 2.0%, respectively.By FDG PET/CT scan, the rates of true positive, false positive, false negative, and true negative were 70.6%, 27.5%, 2.0%, and 0, respectively.18F-PET/CT had a sensitivity of 97.3%(36/37), specificity of 0 (0/14), and accuracy of 70.6%(36/51) in FUO, especially a high sensitivity and accuracy of 100%(9/9) in the diagnosis of malignant tumor .Moreover , the maximum standardized uptake value ( SUVmax ) in tumor was significant higher than that in infection (3.7 ±2.7 vs.7.7 ±3.5, P=0.001, t=3.6), which implied that SUVmax might be useful in differential diagnosis in FUO .Conclusion:FDG PET/CT is a valuable imaging tool for the identification and location of the potential lesion in FUO and is helpful for the etiological diagnosis , especially in the diagnosis of malignant lesions .

Objective To evaluate the usefulness of delayed parenchymal transit time (PTT) on 99TcmDTPA diuretic renography as a predictor for functional improvement after Anderson-Hynes dismembered pyeloplasty in patients with ureteropelvic junction obstruction (UPJO).Methods Forty-seven patients (37males,10 females,age (29.7± 10.8) years) with unilateral U PJO were retrospectively analyzed.All patients underwent 99Tcm-DTPA diuretic renography before and after the surgery.Patient age,sex,UPJO location,surgical methods,relative renal function (RRF) of the diseased kidney (uptake ratio of UPJO kidney to both kidneys),and PTT were recorded.Delayed PTT was defined as having one of the following criteria: (1) photopenic pelvis between the second and seventh frame; (2) relatively stable tracer distribution within the kidney between the second to ninth frame with nearly unchanged kidney shape and size; (3) ever increasing activity in the parenchyma; (4) slower clearance from the parenchyma into the pelvis since the second frame compared with the contralateral healthy kidney.The relationship between the above-mentioned factors and RRF improvement (RRFpvst-surgery,-RRFpre-sugery) was analyzed.Paired t test,Kruskal-Wallis and Mann-Whitney rank sum tests and Pearson correlation analysis were used.Results The average RRF of pre-and post-surgery was (40.70± 13.30) ％ and (44.96 ± 12.60) ％,respectively (t =4.19,P ＜ 0.01).RRF improvement between the delayed group (n=16) and normal timely PTT group (n=27) was significantly different: ((11.69±6.52) ％ vs (0.48±2.98) ％,Z=-5.13,P＜0.01).The assessment of delayed or normal PTT could not be determined in 4 patients.No statistically significant differences of RRF improvement were found between pre-surgery RRF ＜ 40％ and RRF ≥ 40％ groups,between left and right UPJO groups,between open surgery and laparoscope groups,between male and female patients (Z =-1.93 to 1.25,all P＞0.05).There was no significant correlation between RRF improvement and patient age (r =0.01,P＞0.05).Conclusion Delayed PTT on 99Tcm-DTPA diuretic renography might be the predictor for functional improvement post surgery in UPJO patients.

Objective To investigate the clinical value of 18 F?FDG PET/CT in staging multiple myeloma ( MM) and evaluating the glucose metabolic activity of MM. Methods A total of 25 MM patients ( 13 males, 12 females, age:39-67 years) from May 2010 to April 2015 were enrolled in this retrospective study. The SUVmax of each patient was recorded. D?S plus staging according to 18 F?FDG PET/CT was com?pared with the traditional D?S staging. The SUVmax and the percentage of plasmacytes of bone marrow of phase Ⅲ and non?phase Ⅲ ( phaseⅠand Ⅱ) according to D?S plus staging were compared. Two?sample t test and Wilcoxon rank sum test were used to analyze the data. Results In 25 MM patients, the range of SUVmax of lesions was 1.8-12?0 and the mean value was 5.15±2.74. According to D?S staging, the numbers of patients with phase Ⅰ,Ⅱ andⅢwere 7, 4 and 14, respectively. While the numbers were 3, 1 and 21 by D?S plus staging. Based on the D?S plus staging system, stages of 7 patients ( 28%, 7/25 ) were changed. According to the D?S plus staging system, the SUVmax between phaseⅢand non?phaseⅢpatients was significantly different (5.75±2.54 vs 3.00±0?70; t=2.12, P<0.05), while the percentage of plasma?cytes of bone marrow between the 2 groups had no significant difference ( 17. 50%( 4. 25%-41. 75%) vs 11?15%(10.25%-36.57%);z=0.05, P>0.05). Conclusion 18F?FDG PET/CT is of clinical importance for MM staging and metabolic activity assessment of MM.

Objective To explore the value of 18F-FDG PET/CT in diagnosis of retroperitoneal fibrosis (RPF).Methods Totally 12 RPF patients underwent 18 F-FDG PET/CT scanning,and the characteristics of metabolic activity,distribution of retroperitoneal lesions and maximum standardized uptake value (SUVmax) were analyzed retrospectively.Results Among 12 patients,7 were initial evaluation patients,5 were post-treatment patients.Of 7 initial evaluation patients,there were 4 patients with secondary RPF,including prostate carcinoma,breast cancer and IgG4-related disease.Retroperitoneal mass isodense with muscle surrounding the abdominal aorta or the iliac arteries were found in 12 patients,and ureteral involvement were found in 11 paients (11/12,91.67％).SUVmax in initial evaluation patients (4.21±1.76) was higher than that in patients after treatment (1.46±0.25,P＜0.05).According to PET/CT,3 idiopathic RPF patients as initial evaluation with high metabolic activity lesions received immunosuppressive therapy including corticosteroids and tamoxifen,and 4 secondary RPF patients with high metabolic activity lesions received treatment based on causes.Among 5 post-treatment patients,3 continued to accept current corticosteroids maintenance dose,while 2 did not receive any other treatment.Conclusion PET/CT may be used to evaluate the activity and extension of lesions in patients with RPF.

Objective To investigate the characteristics of metabolic foci on 18F-fluorodeoxyglucose (FDG) PET/CT scan in pediatric patients with epilepsy.Methods Twenty-three pediatric patients (15 males,8 females,age range:0.5-13.3 years) with epilepsy were retrospectively reviewed from March 2014 to December 2016.All patients underwent 18F-FDG PET/CT and metabolic foci were found.The visual method and semi-quantitative analysis were used to analyze images.Fourteen of them underwent surgery and were followed up for 3-24 months.Results Glucose hypermetabolism were observed most frequently in the frontal and parietal lobes,with or without surrounding/remote hypometabolism.On the day of PET/CT imaging,8 patients had no seizures,14 patients had seizures,and 1 patient was uncertain.The sites of resection were consistent with the regions of hypermetabolism in 9 patients,among whom the pathological results showed 8 cortical malformations and 1 Rasmussen's syndrome.Follow-up results for the above 9 patients showed that there was 7 Engel class Ⅰ patients and 2 Engel class Ⅲ patients.Conclusion The hypermetabolism may mostly appear in the frontal and parietal lobes of pediatric patients with epilepsy,and malformations of cortical development seem to be the most common pathology results.

Objective To observe the metabolic changes of subcortical structures in children with intractable epilepsy using 18 F-FDG PET/CT,and to investigate the mechanism of subcortical structure involvement in epileptic seizures and its clinical significance.Methods Features of 18F-FDG PET/CT imaging in 611 intractable epilepsy children were analyzed.The metabolic changes of cortex and subcortical structures (basal ganglia,thalamus and cerebellum) were observed.The children were divided into three groups (young,middle and older groups) according to age,also mild group and severe group according to the number of involved lobar,respectively.The incidence of metabolic abnormalities in subcortical structures of different groups were analyzed.Results Among 611 children,unilateral cortical metabolic abnormality was found in 525,and bilateral cortical metabolic abnormalities were found in 86 children.The involvement of subcortical structures was detected in 190 children,including basal ganglia (n=64),thalamus (n=113) and cerebellum (n=105).The incidence of metabolic abnormality in subcortical structures under different age groups was not statistically different (all P＞ 0.05),while the incidence of metabolic abnormality in subcortical structures of severe group was significantly higher than that of mild group (all P＜0.001).Conclusion 18 F-FDG PET/CT might be able to detect the metabolic abnormalities of subcortical structures,therefore indicating the involvement of cerebral cortex.

Objective To investigate the pathogenic bacteria distribution,clinical features and risk factors of urinary tract infection in patients with ischemic stroke. Methods A retrospective study was conducted on 634 patients with ischemic stroke in Beijing Bo'ai Hospital from Janu-ary,2020 to December,2023.They were divided into control group(n=551,without urinary tract infection)and observation group(n=83,with urinary tract infection)according to whether they developed urinary tract infec-tion.The incidence of urinary tract infection,the distribution of pathogenic bacteria and the resistance of main pathogenic bacteria to different antibacterial drugs were analyzed.The clinical characteristics of the two groups were compared and analyzed.The independent risk factors of urinary tract infection in patients with ischemic stroke were analyzed with multivariate Logistic regression. Results A total of 83 cases of 634 patients with ischemic stroke developed urinary tract infection,and incidence was 13.09%.A total of 127 strains of pathogenic bacteria were isolated from the urine samples of the observation group,of which Gram-negative bacteria accounted for 62.99%(80/127),Gram-positive bacteria accounted for 20.47%(26/127)and strains of fungi accounted for 16.54%(21/127).The main Gram-negative pathogens were Escherichia coli and Klebsiella pneumoniae,which were high resistant to second-generation and third-generation cephalosporins,co-trimoxazole,and levofloxacin;moderately resistant to carbapenems,β-lactamase inhibitor compound preparation and aminoglycosides,etc.;and highly sensitive to tigecycline and polymyxin,etc.The main Gram-positive pathogens were Enterococcus faecalis and Enterococcus faecalis,which were a high resistant to erythromycin and gentamicin,and highly sensitive to linezolid,daptomycin,teicoplanin and vancomycin.The pathogenic fungi detected were not obviously resistant to common antifungal drugs.The proportion of female,di-abetes,indwelling catheter and neurogenic bladder were significantly higher in the observation group than in the control group(χ2>5.043,P<0.05).The female,diabetes,indwelling catheter and neurogenic bladder were inde-pendent risk factors for urinary tract infection in patients with ischemic stroke(P<0.05). Conclusion The pathogenic bacteria of patients with ischemic stroke with urinary tract infection are mainly Gram-nega-tive bacteria,followed by Gram-positive bacteria and fungi.The Gram-negative bacteria showed multiple drug re-sistance.Meanwhile,female,diabetes,indentured catheter and neurogenic bladder are the independent risk fac-tors for urinary tract infection.