AIM To identify potential amino acid residues that contribute to different catalytic characteristics of CYP2A6 and CYP2A13 enzymes in nicotine metabolism. METHODSWild type of CYP2A6 and CYP2A13 and their mutants CYP2A6V117A, CYP2A6G164H, CYP2A6I208S, CYP2A6R372H, CYP2A6S465P and CYP2A13A117V, CYP2A13H164G, CYP2A13S208I, CYP2A13H372A and CYP2A13P465S, were subjected kinetic analysis in nicotine 5'-hydroxylation. RESULTS For CYP2A6, substitution of isoleucine 208 to serine caused dramatic kinetic property changes with K_m and V_( max) varied from 62.25 μmol·L~(-1) and 6.53 mol·min~(-1)·moL~(-1) to 345 μmol·L~(-1) and 2.19 mol·min~(-1)·moL~(-1). However, the corresponding serine 208 to isoleucine mutation did not heavily affect the enzyme activity in CYP2A13. The histidine 372 to arginine mutation resulted in a remarkable catalytic efficiency decrease with K_m and V_( max) changes from 26.01 μmol·L~(-1) and 24.51 mol·min~(-1)·moL~(-1) to 148.7 μmol·L~(-1) and 6.11 mol·min~(-1)·moL~(-1) in CYP2A13, but the switching of argenine 372 to histidine did not show expected corresponding crucial influence in CYP2A6 activity. Substitutions on the other positions changed enzyme activities in different rates. CONCLUSION The isoleucine 208 is crucial to human CYP2A6, while the 372 histidine is a key amino acid residue for CYP2A13 in nicotine 5'-hydroxylation.

Objective To analyze the level of Th17 and Treg cells in the peripheral blood of patients with rheumatoid arthritis(RA),and to investigate its role in the pathogenesis of RA and the clinical significance.Methods Flow cytometry(FCM)was used to analyze the ratio of interleukin(IL)-17+CD4+T (Thl7)cells and Foxp3+CD25+CD4+T(Treg)cells in CD4+T cells from the peripheral blood of 57 RA patients and 32 normal controls.T-test and Chi-square test were used for inter-group comparison and Pearson's linear analysis was used for correlation analysis.Resuits Compared with normal controls.the level of both IL-17+CD4+T cells and the ratio of Th17/Treg in RA patients increased significantly.while the level of Foxp3+CD4+CD25+T cells decreased markedly[(4.2±2.2)%vs(2.3±1.4)%,P=0.000;1.15±0.62 I)5 0.34±0.17,P=0.000;(3.9±1.6)%vs(7.0±2.2)%,P=0.000].Compared with early RA(persistent for 2 years or less)patients,the levels of Th17,Treg and the ratio of Th17/Treg in chronic RA(duration for more than 2 years)patients didn't markedly changed(P>0.05).The level of Th17 cells and the ratio of Th17/Treg was directlycorrelated with disease activity parameter (including tender ioint counts,visual analog seale of patients,disease activitv score in 28 joints,etc).Regression analysis discovered that risk factors of bone erosion were the level of Th17 cells,the ratio of Th17/Treg,disease activity score in 28 joints and disease duration.Antirheumatic drugs could decreascthe ratio of Th 17/Treg.Conclusions Treg cells is decreased in RA patients while Th7 cells is increased in patients with RA.Th17/Treg ratio goes up significantly as well.Change of T celt subsets,especially Th17 and Treg cells are important for the pathogenesis of RA.Th17 and Treg cells could aggrevate disease activity and bone destruction throughout the whole disease process.Anti-rheumatic medications is effective by regulating Th17/Treg subset balance.

Objective To investigate the clinical value of GFR, microalbuminuria (mAlb), serum β2-microglobulin (MG) and cystatin C (CysC) for the evaluation of renal function in patients with DN.Methods A total of 150 patients with type 2 DM diagnosed by WHO standard (1999) from December 2012 to December 2015 were retrospectively analyzed.Thirty-three kidney transplantation donors during the same time were chosen as the control group.The urine mAlb, Cr, albumin/Cr ratio(ACR) and SCr, serum β2-MG, CysC, urea, uric acid(UA), fasting blood glucose (FBG), hemoglobin A lc (HbA1c) and C-reactive protein (CRP) were measured.99Tcm-DTPA renal dynamic imaging was performed.The Gates method was used to calculate GFR, and the modification of diet in renal disease (MDRD) method was used to calculate the estimated GFR (eGFR).The relative equation between GFR and eGFR was studied.The clinical stages of renal function in type 2 DM patients were evaluated by Mogenesen standard method.Two-sample t test was used for data analysis.ROC curve analysis was performed to study the diagnostic value of GFR in DN.Results The patients were divided into merely type 2 DM group, early stage DN (Ⅰ, Ⅱ, Ⅲ), and clinical DN(Ⅳ) groups by Mogenesen standard method.GFR and eGFR in the DNⅠstage were higher than those of the merely type 2 DM group (t values:-7.502,-3.629, both P<0.01), and GFR and eGFR decreased with the increased stage of DN.However, serum UA, CRP, FBG and HbA1c, SCr, urea, β2-MG, CysC, mAlb and ACR increased when the stage of DN was higher.GFR and eGFR showed a linear correlation, with the regression equation of y=0.957x+6.823.AUC of ROC in patients with DN Ⅰ was 0.989.With the cutoff value of 125.09 ml/min, the sensitivity and specificity was 96.2%(25/26) and 98.4%(122/124) respectively in diagnosis of DNⅠ.Between high UA and normal UA groups, FBG and HbA1c were not significantly different (t values:-1.010,-1.034, both P>0.05), but the renal function indicators were different (t values:-5.090-2.209, all P<0.01).Compared with the normal CRP group, the FBG, HbA1c and renal function indicators were statistically different in high CRP group (t values:-6.114-7.386, all P<0.01).Conclusions GFR and eGFR show a linear relationship in type 2 DM.GFR is a sensitive, specific diagnostic index in DN Ⅰ period.β2-MG, CysC, mAlb and ACR are conducive to the early diagnosis of DN.High UA is an independent risk factor for the onset of DN, and high CRP is an inflammatory damage factor in DN.

objective To detect the serum macrophage migration inhibitory factor(MIF)and interlbukin (IL)-17,IL-23 levels in rheumatoid arthritis patients with atherosclerosis and to analyze the association between them and their role in the pathogenesis of atherosclerosis in rheumatoid arthritis patients.Methods Total of 69 patients with RA were divided into atherosclerosis group(AS group)and those without atherosclerosis group(NAS group)according to neck vascular ultrasonography.Sixty-four healthy controls(the control group)were also enrolled into this study.MIF and IL-17,IL-23 levels were determined bv ELISA assay.The t test of two independent-samples and One-way ANOVA were used to compare the levels of MIF.IL-17 and IL-23 in different groups of patients and healthy individuals.The correlation between diffrent paramenters was assesed by Pearson's coefficient of correlation and Logistic regression.Results The serum MIF level in the AS group was significantly higher than that in the NAS group and healthy controls(15.2±1.7,13.8±2.2,8.0±2.9,P<0.05),and there were significant correlations between the serum MIF concentration,carotid intima-media thickness(IMT)(r=0.271,P=0.036).the size of atherosclerotic plaques(r=0.291,P=0.024),the serum level of IL-17(r=0.328,P=0.007)and IL-23(r=0.316,p=0.010).The serum IL-17 and IL-23 level in the AS group was higher than healthy controls(2.8±2.0 vs 2.0±0.8,449±174 vs 341±113),while there were no significant differences between AS group and NAS group.The serum MIF level in RA patients was positively correlated with atherosclerosis according to Logistic regression analysis.Conclusion The serum MIF level in RA patients with AS is significantly higher than that in NAS group and healthy controls,and it may be related with the serum level of IL-17 and IL-23.The elevated serum MIF level may be a predictor for atherosclerosis in patients with rheumatoid arthritis.

Objective To study the clinical features, diagnosis and treatment of torsion of testes in newborn. Method Neonates who were diagnosed with neonatal testicular torsion and admitted to Shenzhen Children's Hospital from March 2008 to July 2018 were studied. The clinical data such as days in age, time of onset, clinical manifestations, time of ultrasound examination, characteristics of ultrasound examination, surgery time, surgical types, postoperative conditions, pathological findings, and follow-up results were retrospectively analyzed. Result A total of 12 infants with torsion of testes were enrolled. The average onset time was 2.9 d, ranged from 1～10 d. The time of onset was within 24 h after birth in six infants. The median duration from onset to seeing a doctor was 3.5 d, ranged from 2 h to 28 d. First manifestations being reported grammer were scrotal swelling or mass, including 7 cases on the left side and 5 cases on the right side. Among them, 9 cases were associated with redness or cyanosis of the scrotum. Ultrasound was characterized by the disappearance or significant reduction of testicular parenchymal blood flow signal, and the sensitivity of ultrasound was 100％. The average time from admission to operation was (2.1±1.1) h. All the 12 infants had orchiectomy,after necrosis of unilateral testicle was confirmed. Eight of them underwent contralateral test icular fixation. The average operation time was 46 min. There was no wound bleeding or infection postoperatively, and the average hospital stay was 6.4 d. The pathological features were blurred residual contour of the seminiferous tubule (9 cases) or the disappearance of the seminiferous tubule structure (3 cases). After 3 to 24 months of follow-up, no contralateral testicular torsion or atrophy was found. Conclusion The rate of testicular necrosis in children with torsion of testes is high. The newborn with scrotal swelling should be diagnosed promptly with color Doppler ultrasound. If necessary, surgical exploration should be performed in time.

Objective: Comparison of the efficacy of mini flank incision and laparoscopy in the treatment of infants with ureteropelvic junction obstruction. Methods: We retrospectively analyzed 85 cases of infants with ureteropelvic junction obstruction in our hospital from Jan. 2016 to Jan. 2018, all the patients underwent dismembered pyeloplasty. According to the surgical approach, they were divided into two groups: There were 45 cases in the mini flank incision group, including 39 males and 6 females, aged from 1 month to 3 years, with a median age of 4 months, and 40 patients in the laparoscopy group, including 33 males and 7 females, aged from 2 months to 3 years, with a median age of 9 months. The clinical effects of the two groups were compared. Results: The patients were followed up for 12-24 months. The operation time[(68.0±15.3)min vs.(79.6±18.8)min], fasting time[(5±1)h vs.(14±8)h] and indwelling time of peri-renal drainage tube[(3.1±1.4)d vs.(4.3±2.2)d] in the mini flank incision group were shorter than those in the laparoscopy group (P<0.01), but there was no significant difference in the amount of blood loss[(2.1±0.9)ml vs.(2.2±0.6)ml] during the operation (P>0.05). The recurrence rate[0 vs.5%(2/40)] and the incidence of complications[11.1%(5/45)vs. 17.5%(7/40)] in the mini flank incision group were lower than those in the laparoscopy group, but there was no statistical difference (P>0.05). Conclusions Pyeloplasty via mini flank incision or laparoscopy are both safe, effective and cosmetic.Mini flank incision surgery has the advantage of short operation time, easy to master and less disturbance of physiological function. Pyeloplasty via mini flank incision it is one of the reasonable options for the treatment of infants with ureteropelvic junction obstruction.

Objective:To investigate the characteristic findings of 18F-fluorodeoxyglucose (FDG) PET/CT in patients with adult-onset Still′s disease (AOSD) and the correlation between the maximum standardized uptake value (SUV max) and clinical disease activity score as well as laboratory data. Methods:Twenty-two patients (6 males, 16 females, age range: 19-73 (41.5±16.3) years) with AOSD according to criteria set by Yamaguchi between May 2015 and June 2018 in Nanjing Drum Tower Hospital were recruited in the retrospective study. The characteristic findings of 18F-FDG PET/CT in the consecutive AOSD patients were evaluated. The correlation between SUV max and clinical disease activity score as well as laboratory data was assessed with Spearman rank correlation analysis. Results:PET/CT results contributed to the diagnosis of AOSD in all the 22 patients (100%). The accumulation of 18F-FDG was showed in lymph nodes of 21 patients(95.5%), and the spleen and bone marrow uptake were observed in all the 22 patients (100%). Besides, 18F-FDG uptake was found in shoulder joint ( n=6, 27.3%), submaxillary glands ( n=9, 40.9%) and parotid glands ( n=7, 31.8%). The SUV max of lymph nodes were significantly correlated with the C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR) ( r s values: 0.622, 0.538, both P<0.05). The SUV max of spleen was significantly correlated with CRP and ESR levels ( r s values: 0.543, 0.475, both P<0.05). The SUV max of bone marrow was significantly correlated with the level of CRP and neutrophils(%) ( r s values: 0.497, 0.431, both P<0.05). However, there was no correlation between the SUV max and clinical disease activity score ( r s values: 0.008, 0.102, 0.210, all P>0.05). Conclusions:Characteristics findings of 18F-FDG PET/CT imaging can provide useful information for differential diagnosis as well as extent assessment for AOSD, and play an important role in the diagnosis process of AOSD. 18F-FDG PET/CT scan may be a helpful imaging technique for evaluation of disease activity in patients with AOSD but prospective study with large cohort of individuals are needed.

Objective:To assess the prognostic value of pretreatment 18F-FDG PET/CT metabolic parameters in patients with primary melanoma. Methods:A retrospective analysis comprised of 35 patients (21 males, 14 females, age: 35-85 years; from January 2014 to August 2019; Nanjing Drum Tower Hospital, the Affiliated Hospital of Nanjing University Medical School) who were newly-diagnosed primary melanoma with preoperative 18F-FDG PET/CT was conducted. 18F-FDG PET/CT metabolic parameters including SUV max, SUV mean, peak of SUV (SUV peak) were obtained. Metabolic tumor volume (MTV) and total lesion glycolysis (TLG) of primary focus were measured automatically using the threshold of 40%SUV max. The optimal thresholds of PET parameters were obtained by using ROC curve analysis. The associations between melanoma-specific survival (MSS), progression-free survival (PFS) and PET/CT metabolic parameters were assessed using Kaplan-Meier method and Cox proportional hazards model. Results:The median follow-up was 15.4 months, and 20 patients showed disease progression and 7 died. The cut-off values for SUV max, SUV mean, SUV peak, MTV and TLG were 3.95, 2.45, 2.65, 3.60 cm 3 and 14.85 g, respectively (AUCs: 0.742, 0.790, 0.728, 0.655, 0.693; P values: 0.016, 0.004, 0.022, 0.121, 0.053). Kaplan-Meier method and log-rank test showed that SUV max, SUV mean, SUV peak, MTV and TLG were predictors of PFS ( χ2 values: 4.06-8.35, all P<0.05). Multivariate analysis showed that MTV (hazard ratio ( HR)=3.09, 95% CI: 1.08-8.86, P=0.036) and TLG ( HR=3.36, 95% CI: 1.11-10.14, P=0.031) were significant predictors of PFS but not for MSS ( HR=5.14, P=0.080). Conclusions:SUV max, SUV mean and SUV peak of primary focus may help for predicting PFS of patients with primary melanoma. MTV and TLG of primary focus may be the best to predict PFS of primary melanoma.

Objective:To explore the potential value of interim 18F-fluorodeoxyglucose (FDG) PET/CT combined with B-cell lymphoma-2 (Bcl-2)/MYC protein dual expression (DE) status in the prognostic stratification for patients with primary gastrointestinal diffuse large B-cell lymphoma (PGI-DLBCL). Methods:Forty-six patients (21 males, 25 females; age 20-83 years) with newly diagnosed PGI-DLBCL from June 2012 to May 2019 in Nanjing Drum Tower Hospital were enrolled in this retrospective study. Immunohistochemistry for Bcl-2 and MYC protein expression was performed. All patients underwent baseline and interim (after 2-4 cycles of cyclophosphamide, doxorubicin, vincristine, prednisone, and rituximab (R-CHOP) regimen) 18F-FDG PET/CT scans for assessment. Interim 18F-FDG PET/CT results were determined based on Deauville 5-point scale (DS) and changing rate of maximum standardized uptake value (ΔSUV max%) in 18F-FDG PET/CT images. Kaplan-Meier survival analysis, Cox proportional hazards regression model (single factor, multiple factors analysis) were used to analyze the prognosis (3-year progression free survival (PFS) and overall survival (OS) rates). Results:Patients were followed up for 6-84 months, and 14 showed disease progression and 9 died. The PFS rate and OS rate were 69.6% and 80.4%, respectively. DE, DS as well as ΔSUV max% were significant predictors of PFS (hazard ratio ( HR) values: 3.280, 5.120, 9.167, all P<0.05); lactate dehydrogenase (LDH), MYC protein expression, DS and ΔSUV max% were significant predictors of OS ( HR values: 4.091, 9.618, 7.697, 11.151, all P<0.05). Multivariate analysis revealed that DS and ΔSUV max% were independent predictors of PFS and OS ( HR values: 4.370-9.244, all P<0.05). In the DS negative (-) group, patients with DE positive (+ ) had lower PFS and OS rates than those with DE- (PFS rate: 50.0% vs 88.9%; OS rate: 66.7% vs 96.3%; χ2 values: 6.050, 4.966, both P<0.05). In ΔSUV max%<90% group, patients with DE+ had lower PFS rate than those with DE- (12.5% vs 68.8%; χ2=6.649, P=0.01). Conclusions:Interim PET/CT analysis using DS and ΔSUV max% is able to predict survival in PGI-DLBCL patients. The combination of DS, ΔSUV max% and DE can risk-stratify PGI-DLBCL patient more effectively.

Objective:To assess the prognostic value of pretreatment 18F-FDG PET/CT metabolic parameters in patients with metastatic malignant melanoma treated with anti-programmed cell death-1 (PD1) immunotherapy. Methods:A retrospective analysis of 29 patients (15 males, 14 females, age (59.1±13.0) years) with pathologically diagnosed metastatic malignant melanoma in Nanjing Drum Tower Hospital between June 2017 and October 2020 was conducted. Anti-PD1 immunotherapy were performed in all patients after 18F-FDG PET/CT imaging. 18F-FDG PET/CT parameters including SUV max, bone marrow-to-liver SUV max ratio (BLR), spleen-to-liver SUV max ratio (SLR) were obtained. Total metabolic tumor volume (TMTV) and total lesion glycolysis (TLG) of primary lesions were measured automatically using the thresholds of 40%SUV max. The median value of each PET parameter was regarded as the threshold value and was used to divide patients into 2 groups (≥ and < the median value, respectively). Kaplan-Meier survival curve and Cox proportional risk model were used to analyze the overall survival (OS) differences between groups. Results:The median follow-up time was 15.0 months and 13 patients died. The median OS was 26.0(95% CI: 20.4-31.6) months. The median SUV max, TMTV, TLG, BLR and SLR were 6.2, 8.2 cm 3, 38.6 g, 0.82 and 0.84 respectively. Kaplan-Meier method and log-rank test showed that differences of OS between SUV max≥6.2 and <6.2 groups, TLG≥38.6 g and <38.6 g groups, BLR≥0.82 and <0.82 groups, SLR≥0.84 and <0.84 groups were not significant ( χ2 values: 0.01-0.35, P values: 0.061-0.929), while patients with TMTV≥8.2 cm 3 suffered from poorer OS compared with those with TMTV<8.2 cm 3 ( χ2=5.90, P=0.015). Cox multivariate analysis showed that TMTV (hazard risk ( HR)=6.347, 95% CI: 1.039-38.789) was a significant predictor of OS ( P=0.045). Conclusion:18F-FDG PET/CT parameter TMTV is the independent predictive factor of OS in metastatic melanoma treated with anti-PD1 immunotherapy.